ot Here's Why Men Should Take Probiotics By www.medicinenet.com Published On :: Wed, 27 Jul 2022 00:00:00 PDT Title: Here's Why Men Should Take ProbioticsCategory: Health and LivingCreated: 7/27/2022 12:00:00 AMLast Editorial Review: 7/27/2022 12:00:00 AM Full Article
ot Swimmer's Ear (External Otitis) By www.medicinenet.com Published On :: Wed, 29 Jun 2022 00:00:00 PDT Title: Swimmer's Ear (External Otitis)Category: Diseases and ConditionsCreated: 12/31/1997 12:00:00 AMLast Editorial Review: 6/29/2022 12:00:00 AM Full Article
ot Experimental Drug May Ease Hot Flashes By www.medicinenet.com Published On :: Tue, 14 Jun 2022 00:00:00 PDT Title: Experimental Drug May Ease Hot FlashesCategory: Health NewsCreated: 6/13/2022 12:00:00 AMLast Editorial Review: 6/14/2022 12:00:00 AM Full Article
ot Should You Check Blood Pressure in Both Arms? By www.medicinenet.com Published On :: Thu, 4 Aug 2022 00:00:00 PDT Title: Should You Check Blood Pressure in Both Arms?Category: Health NewsCreated: 8/3/2022 12:00:00 AMLast Editorial Review: 8/4/2022 12:00:00 AM Full Article
ot Health Conditions a Dentist Might Find That Have Nothing to Do With Your Teeth By www.medicinenet.com Published On :: Fri, 12 Aug 2022 00:00:00 PDT Title: Health Conditions a Dentist Might Find That Have Nothing to Do With Your TeethCategory: Health NewsCreated: 8/11/2022 12:00:00 AMLast Editorial Review: 8/12/2022 12:00:00 AM Full Article
ot Changes in Menstrual Cycle Can Come After COVID Shot By www.medicinenet.com Published On :: Mon, 18 Jul 2022 00:00:00 PDT Title: Changes in Menstrual Cycle Can Come After COVID ShotCategory: Health NewsCreated: 7/18/2022 12:00:00 AMLast Editorial Review: 7/18/2022 12:00:00 AM Full Article
ot Scotland Becomes 1st Country to Provide Free Period Products By www.medicinenet.com Published On :: Tue, 16 Aug 2022 00:00:00 PDT Title: Scotland Becomes 1st Country to Provide Free Period ProductsCategory: Health NewsCreated: 8/15/2022 12:00:00 AMLast Editorial Review: 8/16/2022 12:00:00 AM Full Article
ot oteseconazole By www.medicinenet.com Published On :: Fri, 26 Aug 2022 00:00:00 PDT Title: oteseconazoleCategory: MedicationsCreated: 8/26/2022 12:00:00 AMLast Editorial Review: 8/26/2022 12:00:00 AM Full Article
ot MS (Multiple Sclerosis) vs. ALS (Amyotrophic Lateral Sclerosis) By www.medicinenet.com Published On :: Thu, 4 Aug 2022 00:00:00 PDT Title: MS (Multiple Sclerosis) vs. ALS (Amyotrophic Lateral Sclerosis)Category: Diseases and ConditionsCreated: 6/16/2017 12:00:00 AMLast Editorial Review: 8/4/2022 12:00:00 AM Full Article
ot Motion Sickness By www.medicinenet.com Published On :: Mon, 8 Aug 2022 00:00:00 PDT Title: Motion SicknessCategory: Diseases and ConditionsCreated: 5/30/1999 12:00:00 AMLast Editorial Review: 8/8/2022 12:00:00 AM Full Article
ot Major Gene Study Spots DNA Tied to Autism, Other Disorders By www.medicinenet.com Published On :: Fri, 19 Aug 2022 00:00:00 PDT Title: Major Gene Study Spots DNA Tied to Autism, Other DisordersCategory: Health NewsCreated: 8/19/2022 12:00:00 AMLast Editorial Review: 8/19/2022 12:00:00 AM Full Article
ot Erectile Dysfunction (ED, Impotence) By www.medicinenet.com Published On :: Mon, 25 Jul 2022 00:00:00 PDT Title: Erectile Dysfunction (ED, Impotence)Category: Diseases and ConditionsCreated: 12/31/1997 12:00:00 AMLast Editorial Review: 7/25/2022 12:00:00 AM Full Article
ot Picture of Phototoxic Dermatitides By www.medicinenet.com Published On :: Tue, 28 Jun 2022 00:00:00 PDT Title: Picture of Phototoxic DermatitidesCategory: ImagesCreated: 2/23/2010 2:33:00 PMLast Editorial Review: 6/28/2022 12:00:00 AM Full Article
ot Looking for Reliable Hay Fever Advice? It's Probably Not on YouTube By www.medicinenet.com Published On :: Tue, 16 Aug 2022 00:00:00 PDT Title: Looking for Reliable Hay Fever Advice? It's Probably Not on YouTubeCategory: Health NewsCreated: 8/16/2022 12:00:00 AMLast Editorial Review: 8/16/2022 12:00:00 AM Full Article
ot gotu kola By www.medicinenet.com Published On :: Thu, 18 Aug 2022 00:00:00 PDT Title: gotu kolaCategory: MedicationsCreated: 8/18/2022 12:00:00 AMLast Editorial Review: 8/18/2022 12:00:00 AM Full Article
ot CDC Panel Urges Seniors to Get New, More Potent Flu Shot This Fall By www.medicinenet.com Published On :: Thu, 23 Jun 2022 00:00:00 PDT Title: CDC Panel Urges Seniors to Get New, More Potent Flu Shot This FallCategory: Health NewsCreated: 6/23/2022 12:00:00 AMLast Editorial Review: 6/23/2022 12:00:00 AM Full Article
ot Pot Users Are Less Prone to Sinus Problems By www.medicinenet.com Published On :: Tue, 2 Aug 2022 00:00:00 PDT Title: Pot Users Are Less Prone to Sinus ProblemsCategory: Health NewsCreated: 8/1/2022 12:00:00 AMLast Editorial Review: 8/2/2022 12:00:00 AM Full Article
ot Postpartum Depression Can Hit Both Mom & Dad, Sometimes at Same Time By www.medicinenet.com Published On :: Tue, 28 Jun 2022 00:00:00 PDT Title: Postpartum Depression Can Hit Both Mom & Dad, Sometimes at Same TimeCategory: Health NewsCreated: 6/27/2022 12:00:00 AMLast Editorial Review: 6/28/2022 12:00:00 AM Full Article
ot How Do I Increase Serotonin? By www.medicinenet.com Published On :: Tue, 5 Jul 2022 00:00:00 PDT Title: How Do I Increase Serotonin?Category: Diseases and ConditionsCreated: 5/24/2021 12:00:00 AMLast Editorial Review: 7/5/2022 12:00:00 AM Full Article
ot Antibody-mediated protection against respiratory syncytial virus in children By err.ersjournals.com Published On :: 2024-10-09T00:15:15-07:00 Respiratory syncytial virus (RSV) is a major global pathogen, causing lower respiratory tract disease in at-risk populations including young children. Antibodies form a crucial layer of protection from RSV disease, particularly in immunologically naïve infants. Such antibodies are derived from the mother via transplacental transfer and breast milk, but may be particularly low in high-risk infants such as those born preterm. Maternally derived antibodies can now be supplemented by the administration of anti-RSV monoclonal antibodies, while a rising wave of maternal and paediatric vaccine strategies are approaching. The implementation of these prophylactics may profoundly decrease the healthcare burden of RSV. In this article, we review the role of antibody-mediated immunity in protecting children from RSV. We focus on maternally derived antibodies as the main source of protection against RSV and study factors that influence the scale of this transfer. The role of passive and active prophylactic approaches in protecting infants against RSV are discussed and knowledge gaps in our understanding of antibody-mediated protection against RSV are identified. Full Article
ot Dynamic dysregulation of retrotransposons in neurodegenerative diseases at the single-cell level [RESOURCES] By genome.cshlp.org Published On :: 2024-10-29T06:46:08-07:00 Retrotransposable elements (RTEs) are common mobile genetic elements comprising ~42% of the human genome. RTEs play critical roles in gene regulation and function, but how they are specifically involved in complex diseases is largely unknown. Here, we investigate the cellular heterogeneity of RTEs using 12 single-cell transcriptome profiles covering three neurodegenerative diseases, Alzheimer's disease (AD), Parkinson's disease, and multiple sclerosis. We identify cell type marker RTEs in neurons, astrocytes, oligodendrocytes, and oligodendrocyte precursor cells that are related to these diseases. The differential expression analysis reveals the landscape of dysregulated RTE expression, especially L1s, in excitatory neurons of multiple neurodegenerative diseases. Machine learning algorithms for predicting cell disease stage using a combination of RTE and gene expression features suggests dynamic regulation of RTEs in AD. Furthermore, we construct a single-cell atlas of retrotransposable elements in neurodegenerative disease (scARE) using these data sets and features. scARE has six feature analysis modules to explore RTE dynamics in a user-defined condition. To our knowledge, scARE represents the first systematic investigation of RTE dynamics at the single-cell level within the context of neurodegenerative diseases. Full Article
ot Evolutionary dynamics of polyadenylation signals and their recognition strategies in protists [RESEARCH] By genome.cshlp.org Published On :: 2024-10-29T06:46:07-07:00 The poly(A) signal, together with auxiliary elements, directs cleavage of a pre-mRNA and thus determines the 3' end of the mature transcript. In many species, including humans, the poly(A) signal is an AAUAAA hexamer, but we recently found that the deeply branching eukaryote Giardia lamblia uses a distinct hexamer (AGURAA) and lacks any known auxiliary elements. Our discovery prompted us to explore the evolutionary dynamics of poly(A) signals and auxiliary elements in the eukaryotic kingdom. We use direct RNA sequencing to determine poly(A) signals for four protists within the Metamonada clade (which also contains G. lamblia) and two outgroup protists. These experiments reveal that the AAUAAA hexamer serves as the poly(A) signal in at least four different eukaryotic clades, indicating that it is likely the ancestral signal, whereas the unusual Giardia version is derived. We find that the use and relative strengths of auxiliary elements are also plastic; in fact, within Metamonada, species like G. lamblia make use of a previously unrecognized auxiliary element where nucleotides flanking the poly(A) signal itself specify genuine cleavage sites. Thus, despite the fundamental nature of pre-mRNA cleavage for the expression of all protein-coding genes, the motifs controlling this process are dynamic on evolutionary timescales, providing motivation for future biochemical and structural studies as well as new therapeutic angles to target eukaryotic pathogens. Full Article
ot De novo genome assemblies of two cryptodiran turtles with ZZ/ZW and XX/XY sex chromosomes provide insights into patterns of genome reshuffling and uncover novel 3D genome folding in amniotes [RESEARCH] By genome.cshlp.org Published On :: 2024-10-29T06:46:07-07:00 Understanding the evolution of chromatin conformation among species is fundamental to elucidate the architecture and plasticity of genomes. Nonrandom interactions of linearly distant loci regulate gene function in species-specific patterns, affecting genome function, evolution, and, ultimately, speciation. Yet, data from nonmodel organisms are scarce. To capture the macroevolutionary diversity of vertebrate chromatin conformation, here we generate de novo genome assemblies for two cryptodiran (hidden-neck) turtles via Illumina sequencing, chromosome conformation capture, and RNA-seq: Apalone spinifera (ZZ/ZW, 2n = 66) and Staurotypus triporcatus (XX/XY, 2n = 54). We detected differences in the three-dimensional (3D) chromatin structure in turtles compared to other amniotes beyond the fusion/fission events detected in the linear genomes. Namely, whole-genome comparisons revealed distinct trends of chromosome rearrangements in turtles: (1) a low rate of genome reshuffling in Apalone (Trionychidae) whose karyotype is highly conserved when compared to chicken (likely ancestral for turtles), and (2) a moderate rate of fusions/fissions in Staurotypus (Kinosternidae) and Trachemys scripta (Emydidae). Furthermore, we identified a chromosome folding pattern that enables "centromere–telomere interactions" previously undetected in turtles. The combined turtle pattern of "centromere–telomere interactions" (discovered here) plus "centromere clustering" (previously reported in sauropsids) is novel for amniotes and it counters previous hypotheses about amniote 3D chromatin structure. We hypothesize that the divergent pattern found in turtles originated from an amniote ancestral state defined by a nuclear configuration with extensive associations among microchromosomes that were preserved upon the reshuffling of the linear genome. Full Article
ot Evidence for compensatory evolution within pleiotropic regulatory elements [RESEARCH] By genome.cshlp.org Published On :: 2024-10-29T06:46:07-07:00 Pleiotropy, measured as expression breadth across tissues, is one of the best predictors for protein sequence and expression conservation. In this study, we investigated its effect on the evolution of cis-regulatory elements (CREs). To this end, we carefully reanalyzed the Epigenomics Roadmap data for nine fetal tissues, assigning a measure of pleiotropic degree to nearly half a million CREs. To assess the functional conservation of CREs, we generated ATAC-seq and RNA-seq data from humans and macaques. We found that more pleiotropic CREs exhibit greater conservation in accessibility, and the mRNA expression levels of the associated genes are more conserved. This trend of higher conservation for higher degrees of pleiotropy persists when analyzing the transcription factor binding repertoire. In contrast, simple DNA sequence conservation of orthologous sites between species tends to be even lower for pleiotropic CREs than for species-specific CREs. Combining various lines of evidence, we propose that the lack of sequence conservation in functionally conserved pleiotropic CREs is owing to within-element compensatory evolution. In summary, our findings suggest that pleiotropy is also a good predictor for the functional conservation of CREs, even though this is not reflected in the sequence conservation of pleiotropic CREs. Full Article
ot Targeted and complete genomic sequencing of the major histocompatibility complex in haplotypic form of individual heterozygous samples [RESEARCH] By genome.cshlp.org Published On :: 2024-10-29T06:46:07-07:00 The human major histocompatibility complex (MHC) is a ~4 Mb genomic segment on Chromosome 6 that plays a pivotal role in the immune response. Despite its importance in various traits and diseases, its complex nature makes it challenging to accurately characterize on a routine basis. We present a novel approach allowing targeted sequencing and de novo haplotypic assembly of the MHC region in heterozygous samples, using long-read sequencing technologies. Our approach is validated using two reference samples, two family trios, and an African-American sample. We achieved excellent coverage (96.6%–99.9% with at least 30x depth) and high accuracy (99.89%–99.99%) for the different haplotypes. This methodology offers a reliable and cost-effective method for sequencing and fully characterizing the MHC without the need for whole-genome sequencing, facilitating broader studies on this important genomic segment and having significant implications in immunology, genetics, and medicine. Full Article
ot A Comprehensive Guide to Long-Acting Injectable Antipsychotics for Primary Care Clinicians By www.jabfm.org Published On :: 2024-10-25T09:26:14-07:00 We propose a paper that provides education on commonly used long-acting injectable antipsychotics (LAIs) to improve primary care based mental health interventions in patients with severe mental illnesses (SMIs) such as schizophrenia, schizoaffective disorder, and bipolar disorders. With the expanding interface of primary care and psychiatry across all healthcare settings, it has become increasingly important for primary care clinicians to have a broader understanding of common psychiatric treatments, including LAIs. Long-acting injectable antipsychotics have been shown to be helpful in significantly improving treatment adherence, preventing disease progression, improving treatment response, decreasing readmission rates, and reducing social impairment. We discuss evidence-based indications and guidelines for use of long-acting injectable antipsychotics. We provide an overview of the treatment of SMI with LAIs, mainly focusing on the most commonly used long-acting injectable antipsychotics, advantages and disadvantages of each, along with outlining important clinical pearls for ease of practical application. Equipped with increased familiarity and understanding of these essential therapies, primary care clinicians can better facilitate early engagement with psychiatric care, promote more widespread use, and thus significantly improve the wellbeing and quality of life of patients with severe mental illness. Full Article
ot Potential Drawbacks of Noninvasive Diagnostic Methods for Nonalcoholic Fatty Liver Disease By www.jabfm.org Published On :: 2024-10-25T09:26:14-07:00 The rising obesity epidemic is a phenomenon that has gained increasing attention from health providers and health policy makers. This led to recognition of nonalcoholic fatty liver disease (MASLD). The standard for its assessment has been histologic, which is neither practical nor acceptable by patients. Subsequently, a number of noninvasive assessment methods have been developed. However, despite ease of implementation, their confounding variables do hinder their accuracy. Nonetheless, the development of the liver stiffness measurement (LSM) and incorporation of other biological parameters has minimized but not eliminated the need for liver biopsy. Imaging methods are useful in evaluation, estimation, and following the progression of steatosis and fibrosis with particular attention to controlled attenuation parameter (CAP) and MRI–Proton Density Fat Fraction (MRI-PDFF). The choices for the family physician are broad and rely on tests’ availability, cost, and patient acceptance. Great efforts have been undertaken to produce more robust and novel noninvasive markers that indicate fibrinogenesis directly in an implementable and cost-effective way. Full Article
ot How Early Career Family Medicine Women Physicians Negotiate Their First Job After Residency By www.jabfm.org Published On :: 2024-10-25T09:26:14-07:00 Background: Nested within a growing body of evidence of a gender pay gap in medicine are more alarming recent findings from family medicine: a gender pay gap of 16% can be detected at a very early career stage. This article explores qualitative evidence of women’s experiences negotiating for their first job out of residency to ascertain women’s engagement with and approach to the negotiation process. Methods: We recruited family physicians who graduated residency in 2019 and responded to the American Board of Family Medicine 2022 graduate survey. We developed a semistructured interview guide following a modified life history approach to uncover women’s experiences through the transitory stages from residency to workforce. A qualitative researcher used Zoom to interview 19 geographically and racially diverse early career women physicians. Interviews were transcribed verbatim and analyzed using NVivo software following an Inductive Content Analysis approach. Results: Three main themes emerged from the data. First, salary was found to be nonnegotiable, exemplified by participants’ inability to change initial salary offers. Second, the role of peer support throughout residency and early career was crucial to uncovering and rectifying salary inequity. Third, a pay expectation gap was identified among women from minority and low-income households. Conclusion: To rectify the gender pay gap in medicine, a systems-level approach is required. This can be achieved through various levels of interventions: societally expanding the use of and removing the stigma around parental leave, recognizing the importance of contributions not currently valued by productivity-based payment models, examining assumptions about leadership; and institutionally moving away from fee-for-service systems, encouraging flexible schedules, increasing salary transparency, and improving advancement transparency. Full Article
ot Identification and Root Cause Analysis of the Visible Particles Commonly Encountered in the Biopharmaceutical Industry By journal.pda.org Published On :: 2024-10-22T08:20:35-07:00 Visible particle is an important issue in the biopharmaceutical industry, and it may occur across all the stages in the life cycle of biologics. Upon the occurrence of visible particles, it is often necessary to conduct chemical identification and root cause analysis to safeguard the safety and efficacy of the biotherapeutic products. In this article, we present a number of typical particles and relevant root cause analysis in the categories of extrinsic, intrinsic, and inherent particles that are commonly encountered in the biopharma industry. In particular, the optical images of particles obtained both in situ and after isolation are provided, along with spectral and elemental information. The particle identification was carried out with multiple microscopic and microspectroscopic techniques, including stereo optical microscopy, Fourier-transform infrared microscopy, confocal Raman microscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. Both commercial and in-house spectral databases were used for comparison and identification. In addition to particle identification, we placed significant efforts on the root cause analysis of the addressed particles with the intention to provide a relatively whole picture of the particle-related issues and practical references to particle mitigation for our peers in the biopharmaceutical industry. Full Article
ot NEAT1 promotes genome stability via m6A methylation-dependent regulation of CHD4 [Research Papers] By genesdev.cshlp.org Published On :: 2024-10-16T07:18:56-07:00 Long noncoding (lnc)RNAs emerge as regulators of genome stability. The nuclear-enriched abundant transcript 1 (NEAT1) is overexpressed in many tumors and is responsive to genotoxic stress. However, the mechanism that links NEAT1 to DNA damage response (DDR) is unclear. Here, we investigate the expression, modification, localization, and structure of NEAT1 in response to DNA double-strand breaks (DSBs). DNA damage increases the levels and N6-methyladenosine (m6A) marks on NEAT1, which promotes alterations in NEAT1 structure, accumulation of hypermethylated NEAT1 at promoter-associated DSBs, and DSB signaling. The depletion of NEAT1 impairs DSB focus formation and elevates DNA damage. The genome-protective role of NEAT1 is mediated by the RNA methyltransferase 3 (METTL3) and involves the release of the chromodomain helicase DNA binding protein 4 (CHD4) from NEAT1 to fine-tune histone acetylation at DSBs. Our data suggest a direct role for NEAT1 in DDR. Full Article
ot Temperature matters: the potential impact of thermoregulatory mechanisms in brain-body physiology [Special Section: Symposium Outlook] By genesdev.cshlp.org Published On :: 2024-10-16T07:18:56-07:00 Thermoregulation, responsible for maintaining a stable core temperature during wide fluctuations in external and internal thermal environments, is an iconic homeostatic process. However, we suggest that despite its fundamental physiological significance, the potential for required cool housing temperatures and thermoregulatory mechanisms to influence the interpretation of experimental data is not sufficiently appreciated. Moreover, although it is generally assumed that the major thermoregulatory pathways are well understood, here we discuss new research that suggests otherwise and reveals the emergence of a new wave of exciting ideas for this "old" field of research. Full Article
ot Could cough hypersensitivity symptom profile differentiate phenotypes of chronic cough? By beta.openres.ersjournals.com Published On :: 2024-11-11T01:50:25-08:00 Background Recently, cough reflex hypersensitivity has been proposed as a common underlying feature of chronic cough in adults. However, symptoms and clinical characteristics of cough hypersensitivity have not been studied amongst phenotypes of chronic cough. This study aimed to compare symptom features, such as cough triggers and associated throat sensations, of cough hypersensitivity in patients with asthmatic chronic cough and those with refractory chronic cough (RCC). Methods Patients with chronic cough from the Korean Chronic Cough Registry were prospectively evaluated over 6 months. Physicians determined the aetiological diagnosis based on clinical evaluations and responses to treatment at the 6-month follow-up visit. Symptoms of cough hypersensitivity and cough-specific quality of life were assessed using the Cough Hypersensitivity Questionnaire (CHQ) and the Leicester Cough Questionnaire (LCQ), respectively. Results The analysis included 280 patients who completed the follow-up: 79 with asthmatic cough (cough variant asthma or eosinophilic bronchitis) and 201 with RCC. Baseline CHQ scores were similar between the groups (8.3±3.7 in asthmatic cough versus 8.9±3.9 in RCC; p=0.215, adjusted for age, sex and LCQ score). There were no significant between-group differences in the LCQ and cough severity Visual Analog Scale scores. Both groups showed a similar negative correlation with LCQ scores (asthmatic cough: r=–0.427, p<0.001; RCC: r=–0.306, p<0.001). Conclusions The symptoms of cough hypersensitivity may not distinguish between asthmatic cough and RCC. This suggests that chronic cough is the primary diagnosis in both phenotypes. It indicates a shared mechanism in their cough pathogenesis, despite having potentially different treatable traits. Full Article
ot TB or not TB: does AI have an answer for children? By erj.ersjournals.com Published On :: 2024-11-07T00:35:56-08:00 Extract In 2021, the World Health Organization (WHO) issued recommendations for the use of artificial intelligence (AI), affirming the technology could be used instead of human readers for the interpretation of chest radiograph (CXR) images for the screening and triage of tuberculosis (TB), marking a historic precedent for a guideline on AI in health [1]. The forward-looking guidance highlights the utility of CXR in TB, despite past reluctance from WHO to use it in TB programmes [2]. Employing CXR in a diagnostic algorithm can identify people with subclinical TB who are asymptomatic but have lung pathology suggestive of TB, and refer them for testing and diagnosis [3]. Full Article
ot Multidisciplinary management of adult patients with chylothorax: a consensus statement By erj.ersjournals.com Published On :: 2024-11-07T00:35:55-08:00 The management of chylothorax remains challenging given the limited evidence and significant heterogeneity in practice. In addition, there are no practical guidelines on the optimal approach to manage this complex condition. We convened an international group of 27 experts from 20 institutions across five countries and four specialties (pulmonary, interventional radiology, thoracic surgery and nutrition) with experience and expertise in managing adult patients with chylothorax. We performed a literature and internet search for reports addressing seven clinically relevant PICO (Patient, Intervention, Comparison and Outcome) questions pertaining to the management of adult patients with chylothorax. This consensus statement, consisting of best practice statements based on expert consensus addressing these seven PICO questions, was formulated by a systematic and rigorous process involving the evaluation of published evidence, augmented with provider experience. Panel members participated in the development of the final best practice statements using the modified Delphi technique. Our consensus statement aims to offer guidance in clinical decision making when managing patients with chylothorax while also identifying gaps in knowledge and informing future research. Full Article
ot Functional Characterization of Reduced Folate Carrier and Protein-Coupled Folate Transporter for Antifolates Accumulation in Non-Small Cell Lung Cancer Cells [Articles] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 Antifolates are important for chemotherapy in non–small cell lung cancer (NSCLC). They mainly rely on reduced folate carrier (RFC) and proton-coupled folate transporter (PCFT) to enter cells. PCFT is supposed to be the dominant transporter of the two in tumors, as it operates optimally at acidic pH and has limited transport activity at physiological pH, whereas RFC operates optimally at neutral pH. In this study, we found RFC showed a slightly pH-dependent uptake of antifolates, with similar affinity values at pH 7.4 and 6.5. PCFT showed a highly pH-dependent uptake of antifolates, with an optimum pH of 6.0 for pemetrexed and 5.5 for methotrexate. The Michaelis-Menten constant (Km) value of PCFT for pemetrexed at pH 7.4 was more than 10 times higher than that at pH 6.5. Interestingly, we found that antifolate accumulations mediated by PCFT at acidic pH were significantly affected by the efflux transporter, breast cancer resistance protein (BCRP). The highest pemetrexed concentration was observed at pH 7.0–7.4 after a 60-minute accumulation in PCFT-expressing cells, which was further evidenced by the cytotoxicity of pemetrexed, with the IC50 value of pemetrexed at pH 7.4 being one-third of that at pH 6.5. In addition, the in vivo study indicated that increasing PCFT and RFC expression significantly enhanced the antitumor efficacy of pemetrexed despite the high expression of BCRP. These results suggest that both RFC and PCFT are important for antifolates accumulation in NSCLC, although there is an acidic microenvironment and high BCRP expression in tumors. SIGNIFICANCE STATEMENT Evaluating the role of reduced folate carrier (RFC) and proton-coupled folate transporter (PCFT) on antifolates accumulation in non–small cell lung cancer (NSCLC) is necessary for new drug designs. By using cell models, we found both RFC and PCFT were important for antifolates accumulation in NSCLC. Breast cancer resistance protein (BCRP) significantly affected PCFT-mediated antifolates accumulation at acidic pH but not RFC-mediated pemetrexed accumulation at physiological pH. High expression of PCFT or RFC enhanced the cytotoxicity and antitumor effect of pemetrexed. Full Article
ot Effects of Compound Probiotics on Pharmacokinetics of Cytochrome 450 Probe Drugs in Rats [Articles] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 Compound probiotics have been widely used and commonly coadministered with other drugs for treating various chronic illnesses, yet their effects on drug pharmacokinetics remain underexplored. This study elucidated the impact of VSL#3 on the metabolism of probe drugs for cytochrome P450 enzymes (P450s), specifically omeprazole, tolbutamide, midazolam, metoprolol, phenacetin, and chlorzoxazone. Male Wistar rats were administered drinking water containing VSL#3 or not for 14 days and then intragastrically administered a P450 probe cocktail; this was done to investigate the host P450’s metabolic phenotype. Stool, liver/jejunum, and serum samples were collected for 16S ribosomal RNA sequencing, RNA sequencing, and bile acid profiling. The results indicated significant differences in both α and β diversity of intestinal microbial composition between the probiotic and vehicle groups in rats. In the probiotic group, the bioavailability of omeprazole increased by 269.9%, whereas those of tolbutamide and chlorpropamide decreased by 28.1% and 27.4%, respectively. The liver and jejunum exhibited 1417 and 4004 differentially expressed genes, respectively, between the two groups. In the probiotic group, most of P450 genes were upregulated in the liver but downregulated in the jejunum. The expression of genes encoding metabolic enzymes and drug transporters also changed. The serum-conjugated bile acids in the probiotic group were significantly reduced. Shorter duodenal villi and longer ileal villi were found in the probiotic group. In summary, VSL#3 administration altered the gut microbiota, host drug–processing gene expression, and intestinal structure in rats, which could be reasons for pharmacokinetic changes. SIGNIFICANCE STATEMENT This study focused on the effects of the probiotic VSL#3 on the pharmacokinetic profile of cytochrome P450 probe drugs and the expression of host drug metabolism genes. Compared with previous studies, the present study provides a comprehensive explanation for the host drug metabolism profile modified by probiotics, combined here with the bile acid profile and histopathological analysis. Full Article
ot The Simultaneous Inhibition of Solute Carrier Family 6 Member 19 and Breast Cancer Resistance Protein Transporters Leads to an Increase of Indoxyl Sulfate (a Uremic Toxin) in Plasma and Kidney [Articles] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 Solute carrier family 6 member 19 (SLC6A19) inhibitors are being studied as therapeutic agents for phenylketonuria. In this work, a potent SLC6A19 inhibitor (RA836) elevated rat kidney uremic toxin indoxyl sulfate (IDS) levels by intensity (arbitrary unit) of 13.7 ± 7.7 compared with vehicle 0.3 ± 0.1 (P = 0.01) as determined by tissue mass spectrometry imaging analysis. We hypothesized that increased plasma and kidney levels of IDS could be caused by the simultaneous inhibition of both Slc6a19 and a kidney IDS transporter responsible for excretion of IDS into urine. To test this, we first confirmed the formation of IDS through tryptophan metabolism by feeding rats a Trp-free diet. Inhibiting Slc6a19 with RA836 led to increased IDS in these rats. Next, RA836 and its key metabolites were evaluated in vitro for inhibiting kidney transporters such as organic anion transporter (OAT)1, OAT3, and breast cancer resistance protein (BCRP). RA836 inhibits BCRP with an IC50 of 0.045 μM but shows no significant inhibition of OAT1 or OAT3. Finally, RA836 analogs with either potent or no inhibition of SLC6A19 and/or BCRP were synthesized and administered to rats fed a normal diet. Plasma and kidney samples were collected to quantify IDS using liquid chromatography–mass spectrometry. Neither a SLC6A19 inactive but potent BCRP inhibitor nor a SLC6A19 active but weak BCRP inhibitor raised IDS levels, whereas compounds inhibiting both transporters caused IDS accumulation in rat plasma and kidney, supporting the hypothesis that rat Bcrp contributes to the excretion of IDS. In summary, we identified that inhibiting Slc6a19 increases IDS formation, while simultaneously inhibiting Bcrp results in IDS accumulation in the kidney and plasma. SIGNIFICANCE STATEMENT This is the first publication to decipher the mechanism for accumulation of indoxyl sulfate (IDS) (a uremic toxin) in rats via inhibition of both Slc6a19 and Bcrp. Specifically, inhibition of Slc6a19 in the gastrointestinal track increases IDS formation, and inhibition of Bcrp in the kidney blocks IDS excretion. Therefore, we should avoid inhibiting both solute carrier family 6 member 19 and breast cancer resistance protein simultaneously in humans to prevent accumulation of IDS, a known risk factor for cardiovascular disease, psychic anxiety, and mortality in chronic kidney disease patients. Full Article
ot Comparison of the CYP3A Selective Inhibitors CYP3cide, Clobetasol, and Azamulin for Their Potential to Distinguish CYP3A7 Activity in the Presence of CYP3A4/5 [Articles] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 The CYP3A7 enzyme accounts for ~50% of the total cytochrome P450 (P450) content in fetal and neonatal livers and is the predominant P450 involved in neonatal xenobiotic metabolism. Additionally, it is a key player in healthy birth outcomes through the oxidation of dehydroepiandrosterone (DHEA) and DHEA-sulfate. The amount of the other hepatic CYP3A isoforms, CYP3A4 and CYP3A5, expressed in neonates is low but highly variable, and therefore the activity of individual CYP3A isoforms is difficult to differentiate due to their functional similarities. Consequently, a better understanding of the contribution of CYP3A7 to drug metabolism is essential to identify the risk that drugs may pose to neonates and developing infants. To distinguish CYP3A7 activity from CYP3A4/5, we sought to further characterize the selectivity of the specific CYP3A inhibitors CYP3cide, clobetasol, and azamulin. We used three substrate probes, dibenzylfluorescein, luciferin-PPXE, and midazolam, to determine the IC50 and metabolism-dependent inhibition (MDI) properties of the CYP3A inhibitors. Probe selection had a significant effect on the IC50 values and P450 inactivation across all inhibitory compounds and enzymes. CYP3cide and azamulin were both identified as MDIs and were most specific for CYP3A4. Contrary to previous reports, we found that clobetasol propionate (CP) was not an MDI of CYP3A5 but was more selective for CYP3A5 over CYP3A4/7. We further investigated CYP3cide and CP’s ability to differentiate CYP3A7 activity in an equal mixture of recombinant CYP3A4, CYP3A5, and CYP3A7, and our results provide confidence of CYP3cide’s and CP’s ability to distinguish CYP3A7 activity in the presence of the other CYP3A isoforms. SIGNIFICANCE STATEMENT These findings provide valuable insight regarding in vitro testing conditions to investigate the metabolism of new drug candidates and help determine drug safety in neonates. The results presented here also clearly demonstrate the effect that probe selection may have on CYP3A cytochrome P450 inhibition studies. Full Article
ot Quantitative Proteomics for Translational Pharmacology and Precision Medicine: State of The Art and Future Outlook [Minireview] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 Over the past 20 years, quantitative proteomics has contributed a wealth of protein expression data, which are currently used for a variety of systems pharmacology applications, as a complement or a surrogate for activity of the corresponding proteins. A symposium at the 25th North American International Society for the Study of Xenobiotics meeting, in Boston, in September 2023, was held to explore current and emerging applications of quantitative proteomics in translational pharmacology and strategies for improved integration into model-informed drug development based on practical experience of each of the presenters. A summary of the talks and discussions is presented in this perspective alongside future outlook that was outlined for future meetings. SIGNIFICANCE STATEMENT This perspective explores current and emerging applications of quantitative proteomics in translational pharmacology and precision medicine and outlines the outlook for improved integration into model-informed drug development. Full Article
ot Roles of the ABCG2 Transporter in Protoporphyrin IX Distribution and Toxicity [Special Section on New and Emerging Areas and Technologies in Drug Metabolism and Disposition, Part II-Minireview] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 ATP-binding cassette transporter subfamily G member 2 (ABCG2) is a membrane-bound transporter responsible for the efflux of various xenobiotics and endobiotics, including protoporphyrin IX (PPIX), an intermediate in the heme biosynthesis pathway. Certain genetic mutations and chemicals impair the conversion of PPIX to heme and/or increase PPIX production, leading to PPIX accumulation and toxicity. In mice, deficiency of ABCG2 protects against PPIX-mediated phototoxicity and hepatotoxicity by modulating PPIX distribution. In addition, in vitro studies revealed that ABCG2 inhibition increases the efficacy of PPIX-based photodynamic therapy by retaining PPIX inside target cells. In this review, we discuss the roles of ABCG2 in modulating the tissue distribution of PPIX, PPIX-mediated toxicity, and PPIX-based photodynamic therapy. SIGNIFICANCE STATEMENT This review summarized the roles of ABCG2 in modulating PPIX distribution and highlighted the therapeutic potential of ABCG2 inhibitors for the management of PPIX-mediated toxicity. Full Article
ot Exogenous Pregnane X Receptor Does Not Undergo Liquid-Liquid Phase Separation in Nucleus under Cell-Based In Vitro Conditions [Special Section on New and Emerging Areas and Technologies in Drug Metabolism and Disposition, Part II] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 Pregnane X receptor (PXR) belongs to the nuclear receptor superfamily that plays a crucial role in hepatic physiologic and pathologic conditions. Phase separation is a process in which biomacromolecules aggregate and condense into a dense phase as liquid condensates and coexist with a dilute phase, contributing to various cellular and biologic functions. Until now, whether PXR could undergo phase separation remains unclear. This study aimed to investigate whether PXR undergoes phase separation. Analysis of the intrinsically disordered regions (IDRs) using algorithm tools indicated a low propensity of PXR to undergo phase separation. Experimental assays such as hyperosmotic stress, agonist treatment, and optoDroplets assay demonstrated the absence of phase separation for PXR. OptoDroplets assay revealed the inability of the fusion protein of Cry2 with PXR to form condensates upon blue light stimulation. Moreover, phase separation of PXR did not occur even though the mRNA and protein expression levels of PXR target, cytochrome P450 3A4, changed after sorbitol treatment. In conclusion, for the first time, these findings suggested that exogenous PXR does not undergo phase separation following activation or under hyperosmotic stress in nucleus of cells. SIGNIFICANCE STATEMENT PXR plays a critical role in hepatic physiological and pathological processes. The present study clearly demonstrated that exogenous PXR does not undergo phase separation after activation by agonist or under hyperosmotic stress in nucleus. These findings may help understand PXR biology. Full Article
ot Differential Tissue Abundance of Membrane-Bound Drug Metabolizing Enzymes and Transporter Proteins by Global Proteomics [Special Section on New and Emerging Areas and Technologies in Drug Metabolism and Disposition, Part II] By dmd.aspetjournals.org Published On :: 2024-10-16T09:02:03-07:00 Protein abundance data of drug-metabolizing enzymes and transporters (DMETs) are useful for scaling in vitro and animal data to humans for accurate prediction and interpretation of drug clearance and toxicity. Targeted DMET proteomics that relies on synthetic stable isotope-labeled surrogate peptides as calibrators is routinely used for the quantification of selected proteins; however, the technique is limited to the quantification of a small number of proteins. Although the global proteomics-based total protein approach (TPA) is emerging as a better alternative for large-scale protein quantification, the conventional TPA does not consider differential sequence coverage by identifying unique peptides across proteins. Here, we optimized the TPA approach by correcting protein abundance data by the sequence coverage, which was applied to quantify 54 DMETs for characterization of 1) differential tissue DMET abundance in the human liver, kidney, and intestine, and 2) interindividual variability of DMET proteins in individual intestinal samples (n = 13). Uridine diphosphate-glucuronosyltransferase 2B7 (UGT2B7), microsomal glutathione S-transferases (MGST1, MGST2, and MGST3) carboxylesterase 2 (CES2), and multidrug resistance-associated protein 2 (MRP2) were expressed in all three tissues, whereas, as expected, four cytochrome P450s (CYP3A4, CYP3A5, CYP2C9, and CYP4F2), UGT1A1, UGT2B17, CES1, flavin-containing monooxygenase 5, MRP3, and P-glycoprotein were present in the liver and intestine. The top three DMET proteins in individual tissues were: CES1>CYP2E1>UGT2B7 (liver), CES2>UGT2B17>CYP3A4 (intestine), and MGST1>UGT1A6>MGST2 (kidney). CYP3A4, CYP3A5, UGT2B17, CES2, and MGST2 showed high interindividual variability in the intestine. These data are relevant for enhancing in vitro to in vivo extrapolation of drug absorption and disposition and can be used to enhance the accuracy of physiologically based pharmacokinetic prediction of systemic and tissue concentration of drugs. SIGNIFICANCE STATEMENT This study quantified the abundance and compositions of drug-metabolizing enzymes and transporters in pooled human liver, intestine, and kidney microsomes as well as individual intestinal microsomes using an optimized global proteomics approach. The data revealed large intertissue differences in the abundance of these proteins and high intestinal interindividual variability in the levels of cytochrome P450s (e.g., CYP3A4 and CYP3A5), uridine diphosphate-glucuronosyltransferase 2B17, carboxylesterase 2, and microsomal glutathione S-transferase 2. These data are applicable for the prediction of first-pass metabolism and tissue-specific drug clearance. Full Article
ot Inhibitory Actions of Potentiating Neuroactive Steroids in the Human {alpha}1{beta}3{gamma}2L {gamma}-Aminobutyric Acid Type A Receptor [Article] By molpharm.aspetjournals.org Published On :: 2024-10-17T05:12:59-07:00 The -aminobutyric acid type A (GABAA) receptor is modulated by a number of neuroactive steroids. Sulfated steroids and 3β-hydroxy steroids inhibit, while 3α-hydroxy steroids typically potentiate the receptor. Here, we have investigated inhibition of the α1β32L GABAA receptor by the endogenous neurosteroid 3α-hydroxy-5β-pregnan-20-one (3α5βP) and the synthetic neuroactive steroid 3α-hydroxy-5α-androstane-17β-carbonitrile (ACN). The receptors were expressed in Xenopus oocytes. All experiments were done using two-electrode voltage-clamp electrophysiology. In the presence of low concentrations of GABA, 3α5βP and ACN potentiate the GABAA receptor. To reveal inhibition, we conducted the experiments on receptors activated by the combination of a saturating concentration of GABA and propofol to fully activate the receptors and mask potentiation, or on mutant receptors in which potentiation is ablated. Under these conditions, both steroids inhibited the receptor with IC50s of ~13 μM and maximal inhibitory effects of 70–90%. Receptor inhibition by 3α5βP was sensitive to substitution of the α1 transmembrane domain (TM) 2-2' residue, previously shown to ablate inhibition by pregnenolone sulfate. However, results of coapplication studies and the apparent lack of state dependence suggest that pregnenolone sulfate and 3α5βP inhibit the GABAA receptor independently and through distinct mechanisms. Mutations to the neurosteroid binding sites in the α1 and β3 subunits statistically significantly, albeit weakly and incompletely, reduced inhibition by 3α5βP and ACN. SIGNIFICANCE STATEMENT The heteromeric GABAA receptor is inhibited by sulfated steroids and 3β-hydroxy steroids, while 3α-hydroxy steroids are considered to potentiate the receptor. We show here that 3α-hydroxy steroids have inhibitory effects on the α1β32L receptor, which are observed in specific experimental settings and are expected to manifest under different physiological conditions. Full Article
ot Simplified Method for Kinetic and Thermodynamic Screening of Cardiotonic Steroids through the K+-Dependent Phosphatase Activity of Na+/K+-ATPase with Chromogenic pNPP Substrate [Article] By molpharm.aspetjournals.org Published On :: 2024-10-17T05:12:59-07:00 The antitumor effect of cardiotonic steroids (CTS) has stimulated the search for new methods to evaluate both kinetic and thermodynamic aspects of their binding to Na+/K+-ATPase (IUBMB Enzyme Nomenclature). We propose a real-time assay based on a chromogenic substrate for phosphatase activity (pNPPase activity), using only two concentrations with an inhibitory progression curve, to obtain the association rate (kon), dissociation rate (koff), and equilibrium (Ki) constants of CTS for the structure-kinetics relationship in drug screening. We show that changing conditions (from ATPase to pNPPase activity) resulted in an increase of Ki of the cardenolides digitoxigenin, essentially due to a reduction of kon. In contrast, the Ki of the structurally related bufadienolide bufalin increased much less due to the reduction of its koff partially compensating the decrease of its kon. When evaluating the kinetics of 15 natural and semisynthetic CTS, we observed that both kon and koff correlated with Ki (Spearman test), suggesting that differences in potency depend on variations of both kon and koff. A rhamnose in C3 of the steroidal nucleus enhanced the inhibitory potency by a reduction of koff rather than an increase of kon. Raising the temperature did not alter the koff of digitoxin, generating a H (koff) of –10.4 ± 4.3 kJ/mol, suggesting a complex dissociation mechanism. Based on a simple and inexpensive methodology, we determined the values of kon, koff, and Ki of the CTS and provided original kinetics and thermodynamics differences between CTS that could help the design of new compounds. SIGNIFICANCE STATEMENT This study describes a fast, simple, and cost-effective method for the measurement of phosphatase pNPPase activity enabling structure-kinetics relationships of Na+/K+-ATPase inhibitors, which are important compounds due to their antitumor effect and endogenous role. Using 15 compounds, some of them original, this study was able to delineate the kinetics and/or thermodynamics differences due to the type of sugar and lactone ring present in the steroid structure. Full Article
ot Promoting Male Involvement in Family Planning: Insights From the No-Scalpel Vasectomy Program of Davao City, Philippines By ghspjournal.org Published On :: 2024-10-29T12:28:39-07:00 ABSTRACTDespite global consensus on the importance of male involvement in family planning, disparities persist in low- and middle-income countries, where women continue to bear the responsibility for these initiatives. The Philippines, with a high fertility rate and unmet family planning needs, exemplifies this challenge. We present the experiences and lessons learned from implementing the no-scalpel vasectomy (NSV) program in Davao City, showcasing its potential for increasing male engagement in family planning decisions. Launched in 2008, the program aimed to address gender disparity by promoting NSV as a safe and effective contraceptive alternative to female-centric methods. Through the use of culturally sensitive information campaigns and couple-focused counseling, the program challenged traditional notions of masculinity and encouraged shared decision-making. Strong local government commitment and public-private partnerships played key roles in driving the program’s success. Results showed an average annual increase of 80% in NSV clients over the past 3 years compared to before the COVID-19 pandemic, underscoring its effectiveness. The program presents a compelling intervention model for similar initiatives, highlighting how overcoming cultural barriers, infrastructure limitations, and budgetary constraints through policy advocacy, strategic partnerships, and tailored approaches can significantly boost male involvement in family planning and improve reproductive health outcomes within communities. Full Article
ot Development and Piloting of Implementation Strategies to Support Delivery of a Clinical Intervention for Postpartum Hemorrhage in Four sub-Saharan Africa Countries By ghspjournal.org Published On :: 2024-10-29T12:28:39-07:00 ABSTRACTIntroduction:Postpartum hemorrhage (PPH) remains the leading cause of maternal mortality. A new clinical intervention (E-MOTIVE) holds the potential to improve early PPH detection and management. We aimed to develop and pilot implementation strategies to support uptake of this intervention in Kenya, Nigeria, South Africa, and Tanzania.Methods:Implementation strategy development: We triangulated findings from qualitative interviews, surveys and a qualitative evidence synthesis to identify current PPH care practices and influences on future intervention implementation. We mapped influences using implementation science frameworks to identify candidate implementation strategies before presenting these at stakeholder consultation and design workshops to discuss feasibility, acceptability, and local adaptations. Piloting: The intervention and implementation strategies were piloted in 12 health facilities (3 per country) over 3 months. Interviews (n=58), case report forms (n=1,269), and direct observations (18 vaginal births, 7 PPHs) were used to assess feasibility, acceptability, and fidelity.Results:Implementation strategy development: Key influences included shortages of drugs, supplies, and staff, limited in-service training, and perceived benefits of the intervention (e.g., more accurate PPH detection and reduced PPH mortality). Proposed implementation strategies included a PPH trolley, on-site simulation-based training, champions, and audit and feedback. Country-specific adaptations included merging the E-MOTIVE intervention with national maternal health trainings, adapting local PPH protocols, and PPH trollies depending on staff needs. Piloting: Intervention and implementation strategy fidelity differed within and across countries. Calibrated drapes resulted in earlier and more accurate PPH detection but were not consistently used at the start. Implementation strategies were feasible to deliver; however, some instances of limited use were observed (e.g., PPH trolley and skills practice after training).Conclusion:Systematic intervention development, piloting, and process evaluation helped identify initial challenges related to intervention fidelity, which were addressed ahead of a larger-scale effectiveness evaluation. This has helped maximize the internal validity of the trial. Full Article
ot Sensory-Motor Neuropathy in Mfn2 T105M Knock-in Mice and Its Reversal by a Novel Piperine-Derived Mitofusin Activator [Neuropharmacology] By jpet.aspetjournals.org Published On :: 2024-10-18T07:04:15-07:00 Mitochondrial dysfunction is a hallmark of many genetic neurodegenerative diseases, but therapeutic options to reverse mitochondrial dysfunction are limited. While recent studies support the possibility of improving mitochondrial fusion/fission dynamics and motility to correct mitochondrial dysfunction and resulting neurodegeneration in Charcot-Marie-Tooth disease (CMT) and other neuropathies, the clinical utility of reported compounds and relevance of preclinical models are uncertain. Here, we describe motor and sensory neuron dysfunction characteristic of clinical CMT type 2 A in a CRISPR/Casp-engineered Mfn2 Thr105Met (T105M) mutant knock-in mouse. We further demonstrate that daily oral treatment with a novel mitofusin activator derived from the natural product piperine can reverse these neurologic phenotypes. Piperine derivative 8015 promoted mitochondrial fusion and motility in Mfn2-deficient cells in a mitofusin-dependent manner and reversed mitochondrial dysfunction in cultured fibroblasts and reprogrammed motor neurons from a human CMT2A patient carrying the MFN2 T105M mutation. Like previous mitofusin activators, 8015 exhibited stereospecific functionality, but the more active stereoisomer, 8015-P2, is unique in that it has subnanomolar potency and undergoes entero-hepatic recirculation which extends its in vivo half-life. Daily administration of 8015-P2 to Mfn2 T105M knock-in mice for 6 weeks normalized neuromuscular and sensory dysfunction and corrected histological/ultrastructural neurodegeneration and neurogenic myoatrophy. These studies describe a more clinically relevant mouse model of CMT2A and an improved mitofusin activator derived from piperine. We posit that 8015-P2 and other piperine derivatives may benefit CMT2A or other neurodegenerative conditions wherein mitochondrial dysdynamism plays a contributory role. SIGNIFICANCE STATEMENT Mitochondrial dysfunction is widespread and broadly contributory in neurodegeneration, but difficult to target therapeutically. Here, we describe 8015-P2, a new small molecule mitofusin activator with ~10-fold greater potency and improved in vivo pharmacokinetics versus comparators, and demonstrate its rapid reversal of sensory and motor neuron dysfunction in an Mfn2 T105M knock-in mouse model of Charcot-Marie-Tooth disease type 2 A. These findings further support the therapeutic approach of targeting mitochondrial dysdynamism in neurodegeneration. Full Article
ot Gabapentinoids Increase the Potency of Fentanyl and Heroin and Decrease the Potency of Naloxone to Antagonize Fentanyl and Heroin in Rats Discriminating Fentanyl [Behavioral Pharmacology] By jpet.aspetjournals.org Published On :: 2024-10-18T07:04:15-07:00 Despite a significant decrease in the number of prescriptions for opioids, the opioid crisis continues, fueled in large part by the availability of the phenylpiperidine mu opioid receptor (MOR) agonist fentanyl. In contrast, the number of prescriptions for and the off-label use of gabapentinoids (gabapentin and pregabalin) has increased dramatically, with gabapentinoids commonly detected in opioid overdose victims. Although gabapentinoids can decrease the potency of the opioid receptor antagonist naloxone to reverse heroin-induced hypoventilation in male rats, the specificity and nature of interaction between gabapentinoids and MOR agonists and any potential sex difference in those interactions are not well characterized. Gabapentinoids were studied in female and male rats discriminating fentanyl (0.0032 mg/kg, i.p.) or cocaine (3.2 mg/kg, i.p.). Alone, neither gabapentin nor pregabalin significantly increased fentanyl- or cocaine-appropriate responding. In rats discriminating fentanyl, each gabapentinoid dose-dependently shifted the fentanyl and heroin discrimination dose-effect functions to the left, whereas naloxone dose-dependently shifted the fentanyl and heroin discrimination dose-effect functions to the right. Each gabapentinoid (100 mg/kg) significantly decreased the potency of naloxone to antagonize the discriminative stimulus effect of fentanyl or heroin. In contrast, each gabapentinoid dose-dependently shifted the cocaine and d-methamphetamine discrimination dose-effect functions to the right. There were no significant sex differences in this study. These results suggest that gabapentinoids impact the misuse of opioids, the co-use of opioids and stimulant drugs, and the increasing number of overdose deaths in individuals using opioids, stimulant drugs, and gabapentinoids in mixtures. SIGNIFICANCE STATEMENT The number of prescriptions for and the off-label use of gabapentinoids (gabapentin and pregabalin) has increased dramatically, with gabapentinoids commonly detected in opioid overdose victims. This study reports that in rats gabapentinoids increase the potency of fentanyl and heroin to produce discriminative stimulus effects while decreasing the potency of naloxone to antagonize those effects of fentanyl and heroin. These results can help guide policies for regulating gabapentinoids and treating opioid misuse and overdose. Full Article
ot Alternative Reinforcers Enhance the Effects of Opioid Antagonists, but Not Agonists, on Oxycodone Choice Self-Administration in Nonhuman Primates [Behavioral Pharmacology] By jpet.aspetjournals.org Published On :: 2024-10-18T07:04:15-07:00 Clinical reports suggest that the most effective strategies for managing opioid use disorder comprise a comprehensive treatment program of both pharmacological and nonpharmacological approaches. However, the conditions under which these combinations are most effective are not well characterized. This study examined whether the presence of an alternative reinforcer could alter the efficacy of Food and Drug Administration–approved opioid antagonist or agonist medications, as well as the nonopioid flumazenil, in decreasing oxycodone choice self-administration in nonhuman primates. Adult squirrel monkeys (n = 7; four females) responded under concurrent second-order fixed-ratio (FR)-3(FR5:S);TO45s schedules of reinforcement for intravenous oxycodone (0.1 mg/kg) or saline on one lever and 30% sweetened condensed milk or water on the other. Doses of naltrexone (0.00032–1.0 mg/kg), nalbuphine (0.32–10 mg/kg), buprenorphine (0.0032–0.032 mg/kg), methadone (0.32–1.0 mg/kg), or flumazenil (1–3.2 mg/kg) were administered intramuscularly prior to oxycodone self-administration sessions that occurred with either milk or water as the alternative. Naltrexone, a μ-opioid receptor antagonist, was >30-fold more potent when milk was available compared with water and abolished oxycodone intake (injections/session) while concomitantly increasing milk deliveries at the highest dose tested. Pretreatment with the low-efficacy μ-agonist nalbuphine was most effective in the presence of milk compared with water, decreasing oxycodone preference to <50% of control values. The higher efficacy μ-agonists, methadone and buprenorphine, and the benzodiazepine antagonist flumazenil did not appreciably alter the reinforcing potency of oxycodone under either condition. These results suggest that antagonist medications used in combination with alternative reinforcers may be an effective strategy to curtail opioid abuse–related behaviors. SIGNIFICANCE STATEMENT Clinical treatment programs for opioid use disorder use a combination of pharmacological and nonpharmacological approaches. However, the conditions under which these combinations are most effective have not been fully characterized. This study examined whether the effectiveness of μ-opioid medications to decrease oxycodone self-administration is altered in the presence of an alternative reinforcer. The results suggest that alternative reinforcers enhance the effects of antagonist or low-efficacy partial agonists, suggesting they may be a more effective strategy to curtail opioid use. Full Article
ot Proteomic Analysis of Signaling Pathways Modulated by Fatty Acid Binding Protein 5 (FABP5) in Macrophages [Special Section: Cannabinoid Signaling in Human Health and Disease] By jpet.aspetjournals.org Published On :: 2024-10-18T07:04:15-07:00 Although acute inflammation serves essential functions in maintaining tissue homeostasis, chronic inflammation is causally linked to many diseases. Macrophages are a major cell type that orchestrates inflammatory processes. During inflammation, macrophages undergo polarization and activation, thereby mobilizing pro-inflammatory and anti-inflammatory transcriptional programs that regulate ensuing macrophage functions. Fatty acid binding protein 5 (FABP5) is a lipid chaperone highly expressed in macrophages. FABP5 deletion is implicated in driving macrophages toward an anti-inflammatory phenotype, yet signaling pathways regulated by macrophage-FABP5 have not been systematically profiled. We leveraged proteomic and phosphoproteomic approaches to characterize pathways modulated by FABP5 in M1 and M2 polarized bone marrow-derived macrophages (BMDMs). Stable isotope labeling by amino acids-based analysis of M1 and M2 polarized wild-type and FABP5 knockout BMDMs revealed numerous differentially regulated proteins and phosphoproteins. FABP5 deletion impacted downstream pathways associated with inflammation, cytokine production, oxidative stress, and kinase activity. Toll-like receptor 2 (TLR2) emerged as a novel target of FABP5 and pharmacological FABP5 inhibition blunted TLR2-mediated activation of downstream pathways, ascribing a novel role for FABP5 in TLR2 signaling. This study represents a comprehensive characterization of the impact of FABP5 deletion on the proteomic and phosphoproteomic landscape of M1 and M2 polarized BMDMs. Loss of FABP5 altered pathways implicated in inflammatory responses, macrophage function, and TLR2 signaling. This work provides a foundation for future studies seeking to investigate the therapeutic potential of FABP5 inhibition in pathophysiological states resulting from dysregulated inflammatory signaling. SIGNIFICANCE STATEMENT This research offers a comprehensive analysis of fatty acid binding protein 5 (FABP5) in macrophages during inflammatory response. The authors employed quantitative proteomic and phosphoproteomic approaches to investigate this utilizing bone marrow-derived macrophages that were M1 and M2 polarized using lipopolysaccharide with interferon and interleukin-4, respectively. This revealed multiple pathways related to inflammation that were differentially regulated due to the absence of FABP5. These findings underscore the potential therapeutic significance of macrophage-FABP5 as a candidate for addressing inflammatory-related diseases. Full Article