Betsy B. Dokken
Jul 1, 2008; 21:160-165
From Research to Practice/Cardiovascular Disease and Diabetes

Companies with large numbers of furloughed workers are offering staff an introductory course in JavaScript coding, thanks to the European coding bootcamp, Codeworks.

(Stony Brook University) In evolutionary terms, islands are the stuff of weirdness. It is on islands where animals evolve in isolation, often for millions of years, with different food sources, competitors, predators, and parasites...indeed, different everything compared to mainland species. As a result, they develop into different shapes and sizes and evolve into new species that, given enough time, spawn yet more new species.

(American Geriatrics Society) The American Geriatrics Society (AGS) will this year honor past AGS President Todd Semla, PharmD, MS, AGSF, with the prestigious Nascher/Manning Award, given biannually at the AGS Annual Scientific Meeting (#AGS21, to be held next year May 13-15 in Chicago, Ill., following the cancellation of the AGS 2020 Annual Scientific Meeting due to COVID-19).

7 May 2020 , Volume 96, Number 3

Radionuclide imaging of myocardial perfusion, function, and viability has been established for decades and remains a robust, evidence-based and broadly available means for clinical workup and therapeutic guidance in ischemic heart disease. Yet, powerful alternative modalities have emerged for this purpose, and their growth has resulted in increasing competition. But the potential of the tracer principle goes beyond the assessment of physiology and function, towards the interrogation of biology and molecular pathways. This is a unique selling point of radionuclide imaging, which has been under-recognized in cardiovascular medicine until recently. Now, molecular imaging methods for the detection of myocardial infiltration, device infection and cardiovascular inflammation are successfully gaining clinical acceptance. This is further strengthened by the symbiotic quest of cardiac imaging and therapy for an increasing implementation of molecular-targeted procedures, where specific therapeutic interventions require specific diagnostic guidance towards the most suitable candidates. This review will summarize the current advent of clinical cardiovascular molecular imaging and highlight its transformative contribution to the evolution of cardiovascular therapy beyond mechanical interventions and broad "blockbuster" medication, towards a future of novel, individualized molecular targeted and molecular imaging-guided therapies.

Gemma Cadby
Apr 1, 2020; 61:537-545
Patient-Oriented and Epidemiological Research

7 May 2020 , Volume 96, Number 3

CVD is the leading cause of death worldwide, and genetic investigations into the human lipidome may provide insight into CVD risk. The aim of this study was to estimate the heritability of circulating lipid species and their genetic correlation with CVD traits. Targeted lipidomic profiling was performed on 4,492 participants from the Busselton Family Heart Study to quantify the major fatty acids of 596 lipid species from 33 classes. We estimated narrow-sense heritabilities of lipid species/classes and their genetic correlations with eight CVD traits: BMI, HDL-C, LDL-C, triglycerides, total cholesterol, waist-hip ratio, systolic blood pressure, and diastolic blood pressure. We report heritabilities and genetic correlations of new lipid species/subclasses, including acylcarnitine (AC), ubiquinone, sulfatide, and oxidized cholesteryl esters. Over 99% of lipid species were significantly heritable (h²: 0.06–0.50) and all lipid classes were significantly heritable (h²: 0.14–0.50). The monohexosylceramide and AC classes had the highest median heritabilities (h² = 0.43). The largest genetic correlation was between clinical triglycerides and total diacylglycerol (r_g = 0.88). We observed novel positive genetic correlations between clinical triglycerides and phosphatidylglycerol species (r_g: 0.64–0.82), and HDL-C and alkenylphosphatidylcholine species (r_g: 0.45–0.74). Overall, 51% of the 4,768 lipid species-CVD trait genetic correlations were statistically significant after correction for multiple comparisons. This is the largest lipidomic study to address the heritability of lipids and their genetic correlation with CVD traits. Future work includes identifying putative causal genetic variants for lipid species and CVD using genome-wide SNP and whole-genome sequencing data.

Lipid rafts are highly ordered regions of the plasma membrane that are enriched in cholesterol and sphingolipids and play important roles in many cells. In hematopoietic stem and progenitor cells (HSPCs), lipid rafts house receptors critical for normal hematopoiesis. Lipid rafts also can bind and sequester kinases that induce negative feedback pathways to limit proliferative cytokine receptor cycling back to the cell membrane. Modulation of lipid rafts occurs through an array of mechanisms, with optimal cholesterol efflux one of the major regulators. As such, cholesterol homeostasis also regulates hematopoiesis. Increased lipid raft content, which occurs in response to changes in cholesterol efflux in the membrane, can result in prolonged receptor occupancy in the cell membrane and enhanced signaling. In addition, certain diseases, like diabetes, may contribute to lipid raft formation and affect cholesterol retention in rafts. In this review, we explore the role of lipid raft-related mechanisms in hematopoiesis and CVD (specifically, atherosclerosis) and discuss how defective cholesterol efflux pathways in HSPCs contribute to expansion of lipid rafts, thereby promoting myelopoiesis and thrombopoiesis. We also discuss the utility of cholesterol acceptors in contributing to lipid raft regulation and disruption, and highlight the potential to manipulate these pathways for therapeutic gain in CVD as well as other disorders with aberrant hematopoiesis.

Hypo-vascularised diabetic non-healing wounds are due to reduced number and impaired physiology of endogenous endothelial progenitor cell (EPC) population that, limits their recruitment and mobilization at the wound site. To enrich the EPC repertoire from non-endothelial precursors, abundantly available mesenchymal stromal cells (MSCs) were reprogrammed into induced-endothelial cells (iECs). We identified cell signaling molecular targets by meta-analysis of microarray datasets. BMP-2 induction leads to the expression of inhibitory Smad 6/7-dependent negative transcriptional regulation of ID1, rendering the latter's reduced binding to TWIST1 during transdifferentiation of WJ-MSC into iEC. TWIST1, in turn, regulates endothelial genes transcription, positively of pro-angiogenic-KDR and negatively, in part, of anti-angiogenic-SFRP4. Twist1 reprogramming enhanced the endothelial lineage commitment of WJ-MSC, increased the vasculogenic potential of reprogrammed EC (rEC). Transplantation of stable TWIST1-rECs into full-thickness type 1 and 2 diabetic-splinted wound healing murine model enhanced the microcirculatory blood flow and accelerated the wound tissue regeneration. An increased or decreased co-localization of GFP with KDR/SFRP4 and CD31 in the regenerated diabetic wound bed with TWIST1 overexpression or silencing (piLenti-TWIST1-shRNA-GFP), respectively further confirmed improved neovascularization. This study depicted the reprogramming of WJ-MSCs into rECs using unique transcription factors, TWIST1 for an efficacious cell transplantation therapy to induce neovascularization–mediated diabetic wound tissue regeneration.

Diabetes is now a pandemic disease. Moreover, a large number of people with prediabetes are at risk for developing frank diabetes worldwide. Both type 1 and type 2 diabetes increase the risk of atherosclerotic cardiovascular disease (CVD). Even with statin treatment to lower LDL cholesterol, patients with diabetes have a high residual CVD risk. Factors mediating the residual risk are incompletely characterized. An attractive hypothesis is that remnant lipoprotein particles (RLPs), derived by lipolysis from VLDL and chylomicrons, contribute to this residual risk. RLPs constitute a heterogeneous population of lipoprotein particles, varying markedly in size and composition. Although a universally accepted definition is lacking, for the purpose of this review we define RLPs as postlipolytic partially triglyceride-depleted particles derived from chylomicrons and VLDL that are relatively enriched in cholesteryl esters and apolipoprotein (apo)E. RLPs derived from chylomicrons contain apoB48, while those derived from VLDL contain apoB100. Clarity as to the role of RLPs in CVD risk is hampered by lack of a widely accepted definition and a paucity of adequate methods for their accurate and precise quantification. New specific methods for RLP quantification would greatly improve our understanding of their biology and role in promoting atherosclerosis in diabetes and other disorders.

Endorepellin, the C-terminal fragment of the heparan sulfate proteoglycan perlecan, influences various signaling pathways in endothelial cells by binding to VEGFR2. In this study, we discovered that soluble endorepellin activates the canonical stress signaling pathway consisting of PERK, eIF2α, ATF4, and GADD45α. Specifically, endorepellin evoked transient activation of VEGFR2, which, in turn, phosphorylated PERK at Thr980. Subsequently, PERK phosphorylated eIF2α at Ser51, upregulating its downstream effector proteins ATF4 and GADD45α. RNAi-mediated knockdown of PERK or eIF2α abrogated the endorepellin-mediated up-regulation of GADD45α, the ultimate effector protein of this stress signaling cascade. To functionally validate these findings, we utilized an ex vivo model of angiogenesis. Exposure of the aortic rings embedded in 3D fibrillar collagen to recombinant endorepellin for 2–4 h activated PERK and induced GADD45α vis à vis vehicle-treated counterparts. Similar effects were obtained with the established cellular stress inducer tunicamycin. Notably, chronic exposure of aortic rings to endorepellin for 7–9 days markedly suppressed vessel sprouting, an angiostatic effect that was rescued by blocking PERK kinase activity. Our findings unravel a mechanism by which an extracellular matrix protein evokes stress signaling in endothelial cells, which leads to angiostasis.

Barbara H. Braffett
May 1, 2020; 69:1000-1010
Complications

Mario Luca Morieri
Apr 1, 2020; 69:771-783
Genetics/Genomes/Proteomics/Metabolomics

This special issue focuses on Cardiovascular Concerns with Diabetes an COVID-19. 

Recorded April 19, 2020.

This is a part of the American Diabetes Associations ongoing project providing resources for practicing clinicians on the care of Diabetes during the Covid-19 pandemic.  Todays discussion is an audio version of a webinar recorded on April 19, 2020.

Presented by:

Neil Skolnik, M.D., Professor of Family and Community Medicine, Sidney Kimmel Medical College, Thomas Jefferson University; Associate Director, Family Medicine Residency Program, Abington Jefferson Health

John J. Russell, M.D., Professor of Family and Community Medicine, Sidney Kimmel Medical College, Thomas Jefferson University; Director, Family Medicine Residency Program, Chair-Department of Family Medicine, Abington Jefferson Health

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This is one of the very most exciting internet sites I have actually ever observed. It is very exciting considering that of its one-of-a-kind subject matter and also amazing short articles.

KINGSTON COLLEGE (KC) principal Dave Myrie has refuted claims that St Jago High School sprint hurdler Vashaun Vascianna will be joining the school this September. The Gleaner understands that Vascianna, who broke the Class Two boys’ 110m hurdles...

Michael P Stern
Apr 1, 1995; 44:369-374
Perspectives in Diabetes

Cindy J.M. Loomans
Jan 1, 2004; 53:195-199
Complications

T Inoguchi
Nov 1, 2000; 49:1939-1945
Articles

ME Griffin
Jun 1, 1999; 48:1270-1274
Articles

Lipodystrophies are a group of disorders characterized by absence or loss of adipose tissue and abnormal fat distribution, commonly accompanied by metabolic dysregulation. Although considered rare disorders, their prevalence in the general population is not well understood. We aimed to evaluate the clinical and genetic prevalence of lipodystrophy disorders in a large clinical care cohort. We interrogated the electronic health record (EHR) information of >1.3 million adults from the Geisinger Health System for lipodystrophy diagnostic codes. We estimate a clinical prevalence of disease of 1 in 20,000 individuals. We performed genetic analyses in individuals with available genomic data to identify variants associated with inherited lipodystrophies and examined their EHR for comorbidities associated with lipodystrophy. We identified 16 individuals carrying the p.R482Q pathogenic variant in LMNA associated with Dunnigan familial partial lipodystrophy. Four had a clinical diagnosis of lipodystrophy, whereas the remaining had no documented clinical diagnosis despite having accompanying metabolic abnormalities. We observed a lipodystrophy-associated variant carrier frequency of 1 in 3,082 individuals in our cohort with substantial burden of metabolic dysregulation. We estimate a genetic prevalence of disease of ~1 in 7,000 in the general population. Partial lipodystrophy is an underdiagnosed condition. and its prevalence, as defined molecularly, is higher than previously reported. Genetically guided stratification of patients with common metabolic disorders, like diabetes and dyslipidemia, is an important step toward precision medicine.

The cardiovascular benefits of fibrates have been shown to be heterogeneous and to depend on the presence of atherogenic dyslipidemia. We investigated whether genetic variability in the PPARA gene, coding for the pharmacological target of fibrates (PPAR-α), could be used to improve the selection of patients with type 2 diabetes who may derive cardiovascular benefit from addition of this treatment to statins. We identified a common variant at the PPARA locus (rs6008845, C/T) displaying a study-wide significant influence on the effect of fenofibrate on major cardiovascular events (MACE) among 3,065 self-reported white subjects treated with simvastatin and randomized to fenofibrate or placebo in the ACCORD-Lipid trial. T/T homozygotes (36% of participants) experienced a 51% MACE reduction in response to fenofibrate (hazard ratio 0.49; 95% CI 0.34–0.72), whereas no benefit was observed for other genotypes (P_interaction = 3.7 x 10^–4). The rs6008845-by-fenofibrate interaction on MACE was replicated in African Americans from ACCORD (N = 585, P = 0.02) and in external cohorts (ACCORD-BP, ORIGIN, and TRIUMPH, total N = 3059, P = 0.005). Remarkably, rs6008845 T/T homozygotes experienced a cardiovascular benefit from fibrate even in the absence of atherogenic dyslipidemia. Among these individuals, but not among carriers of other genotypes, fenofibrate treatment was associated with lower circulating levels of CCL11—a proinflammatory and atherogenic chemokine also known as eotaxin (P for rs6008845-by-fenofibrate interaction = 0.003). The GTEx data set revealed regulatory functions of rs6008845 on PPARA expression in many tissues. In summary, we have found a common PPARA regulatory variant that influences the cardiovascular effects of fenofibrate and that could be used to identify patients with type 2 diabetes who would derive benefit from fenofibrate treatment, in addition to those with atherogenic dyslipidemia.

Insulin-mediated microvascular recruitment (IMVR) regulates delivery of insulin and glucose to insulin-sensitive tissues. We have previously proposed that perivascular adipose tissue (PVAT) controls vascular function through outside-to-inside communication and through vessel-to-vessel, or "vasocrine," signaling. However, direct experimental evidence supporting a role of local PVAT in regulating IMVR and insulin sensitivity in vivo is lacking. Here, we studied muscles with and without PVAT in mice using combined contrast-enhanced ultrasonography and intravital microscopy to measure IMVR and gracilis artery diameter at baseline and during the hyperinsulinemic-euglycemic clamp. We show, using microsurgical removal of PVAT from the muscle microcirculation, that local PVAT depots regulate insulin-stimulated muscle perfusion and glucose uptake in vivo. We discovered direct microvascular connections between PVAT and the distal muscle microcirculation, or adipomuscular arterioles, the removal of which abolished IMVR. Local removal of intramuscular PVAT altered protein clusters in the connected muscle, including upregulation of a cluster featuring Hsp90ab1 and Hsp70 and downregulation of a cluster of mitochondrial protein components of complexes III, IV, and V. These data highlight the importance of PVAT in vascular and metabolic physiology and are likely relevant for obesity and diabetes.