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Venkatesan, T.

Publications and source records attributed to Venkatesan, T..

2 recordsLinked to original sources

Atorvastatin suppresses cardiac fibrosis and dysfunction induced by HIV and certain antiretroviral drugs in mice by blocking platelet TGFβ1

Cardiovascular disease (CVD) both atherosclerosis-related and heart failure with preserved ejection fraction (HFpEF) and linked to cardiac fibrosis, contributes to morbidity and mortality in people with HIV (PWH) receiving antiretroviral therapy (ART). In the REPRIEVE trial, pitavastatin reduced atherosclerotic CVD risk to a magnitude inconsistent with pitavastatins impact solely on LDL-cholesterol and inflammation. We hypothesized that HFpEF in PWH relates to HIV-induced fibrosis mediated by platelet TGF{beta}1, that it is accelerated by certain contemporary ART, and may also be inhibited by statins. ART drugs used in REPRIEVE, including a nucleoside/nucleotide, integrase inhibitor-based regimen (tenofovir (TDF), emtricitabine (FTC), and dolutegravir (DTG)), and the protease inhibitors ritonavir (RTV) and darunavir (DRV), and the impact of atorvastatin, were examined in two HIV mouse models: transgenic Tg26 mice and HIV-PDX mice engrafted with HIV-infected T cells. Tg26 and HIV-PDX mice had higher cardiac fibrosis than littermate controls without HIV (p<0.05). Administration of TDF-FTC-DTG or RTV, but not DRV, resulted in a further [~]2-fold increase in fibrosis (p<0.01). Higher cardiac fibrosis with intracardiac fat accumulation correlated with reduced diastolic function. Mice depleted of platelet TGF{beta}1 (TGF{beta}1Platelet-{Delta}Tg26), or treated with atorvastatin, were partially protected from HIV- and ART-induced cardiac fibrosis, steatosis, and diastolic dysfunction. Atorvastatin effects occurred independently of changes in inflammatory cytokines and total cholesterol. They correlated with reduced platelet activation and TGF{beta}1 signaling in cardiac endothelial cells, fibroblasts, and macrophages undergoing mesenchymal transition. These results indicate that certain ART regimens accelerate HIV-associated CVD characterized by HFpEF via platelet TGF{beta}1-dependent processes and mitigated by atorvastatin. They enhance understanding of the pleiotropic effects of statins in HIV/ART CVD and suggest a mechanism that might be targeted by antiplatelet agents or inhibition of TGF{beta} signaling. Key PointsO_LIContemporary ART regimens induce release of platelet TGF{beta}1 and are associated with cardiac fibrosis and diastolic dysfunction with ectopic fat deposition in HIV-infected mice. C_LIO_LIDepleting platelet TGF{beta}1 and/or treating with atorvastatin therapy suppresses HIV-ART-induced cardiac fibrosis, suggesting use of anti-platelet strategies to prevent heart failure among PWH. C_LI

biochemistry↗

High-resolution genetic and phenotypic analysis of KIR2DL1 alleles and their association with pre-eclampsia

Killer-cell immunoglobulin-like receptor (KIR) genes are inherited as haplotypes, expressed by NK cells and linked to outcomes of infectious diseases and pregnancy. Understanding how genotype relates to phenotype is difficult because of the extensive diversity of the KIR family. Indeed, high-resolution KIR genotyping and phenotyping in single NK cells in the context of disease association is lacking. Here, we describe a new method to separate NK cells expressing allotypes of the KIR2DL1 gene carried by the KIR A haplotype (KIR2DL1A) from those expressing KIR2DL1 alleles carried by the KIR B haplotype (KIR2DL1B). We find that in KIR AB heterozygous individuals, different KIR2DL1 allotypes can be detected both in peripheral blood and in uterine single NK cells. Using this new method, we demonstrate that both blood and uterine NK cells co-dominantly express KIR2DL1A and KIR2DL1B allotypes, but with a predominance of KIR2DL1A variants, which associate with enhanced NK cell function. In a case-control study of pre-eclampsia, we show that KIR2DL1A, not KIR2DL1B, associates with increased disease risk. This method will facilitate our understanding of how individual KIR2DL1 allelic variants affect NK cell function and contribute to disease risk.

immunology↗