Lipolytic Rate Associated With Intramyocardial Lipid in an HIV Cohort Without Increased Lipolysis

Abstract

To our knowledge, this study is among the first in humans to characterize the relationship between lipid deposition in the myocardium and direct measurement of whole-body fatty acid metabolism. Our current findings contribute to the growing understanding of factors that promote myocardial steatosis, such as visceral adiposity, and implicate lipolysis as a potential target for interventions to optimize myocardial health.

Genetic and cytometric analyses of subcutaneous adipose tissue in patients with hemophilia and HIV-associated lipodystrophy

“…Our results may help elucidate the etiology of fat redistribution in patients with HIV. The accumulation of visceral fat after HIV infection is often accompanied by systemic inflammation, insulin resistance, dyslipidemia and an increased risk of cardiovascular diseases [ 46 , 47 ]; very similar to the profile of patients with metabolic syndrome. Although the acute phase of inflammation accelerates lipolysis, chronic inflammation causes insulin resistance which is strongly associated with dysregulated lipolysis and dyslipidemia (increased triglycerides).…”

Myocardial steatosis across the spectrum of human health and disease

“…Several mechanisms may contribute to an increase TA B L E 2 Myocardial triglyceride content in special populations. Neilan et al, 2020;Toribio et al, 2019), body mass index (Lai et al, 2017;Neilan et al, 2020), ectopic body fat deposition (Chew et al, 2017;Diaz-Zamudio et al, 2015;Howard et al, 2016;Thiara et al, 2015) and even duration of anti-retroviral therapy (Lai et al, 2017;Nelson et al, 2014). Sex does not appear to influence this association, with myocardial triglyceride content elevated in both men and women with HIV.…”

“…Indeed, myocardial triglyceride content is often elevated among individuals with HIV, and associated with worsening LV systolic and diastolic function (Holloway et al., 2013 ; Nelson et al., 2014 ; Shitole et al., 2023 ; Thiara et al., 2015 ; Toribio et al., 2019 ). Several mechanisms may contribute to an increase in myocardial triglyceride content with HIV, including age (Chew et al., 2017 ; Neilan et al., 2020 ; Toribio et al., 2019 ), body mass index (Lai et al., 2017 ; Neilan et al., 2020 ), ectopic body fat deposition (Chew et al., 2017 ; Diaz‐Zamudio et al., 2015 ; Howard et al., 2016 ; Thiara et al., 2015 ) and even duration of anti‐retroviral therapy (Lai et al., 2017 ; Nelson et al., 2014 ). Sex does not appear to influence this association, with myocardial triglyceride content elevated in both men and women with HIV.…”

Adipose Tissue in HIV Infection

“…Non-alcoholic hepatic steatosis was estimated to affect 40–55% of HIV-infected subjects in several recent series using non-invasive elastography (147, 155, 243, 265), and notably the condition often occurs in individuals with lower BMI and greater physical activity as compared to cases in the general population (175). Abnormal fat deposition is not limited to the liver in HIV infection, and intramyocellular and intramyocardial lipid accumulation is also common, among other body compartments (107, 150, 250, 255). Furthermore, elevated free fatty acids from accelerated lipolysis appear to be a central factor in the infiltration and proliferation of CD4+ T cells in adipose tissue, which contributes to the local macrophage activation, the inflammatory milieu (described further below), and dysregulation of adipocyte function (86, 109, 284).…”