Association between hepatic fat and subclinical vascular disease burden in the general population

ObjectiveIt is still controversial if increased hepatic fat independently contributes to cardiovascular risk. We aimed to assess the association between hepatic fat quantified by MRI and various subclinical vascular disease parameters.DesignWe included two cross-sectional investigations embedded in two independent population-based studies (Study of Health in Pomerania (SHIP): n=1341; Cooperative Health Research in the Region of Augsburg (KORA): n=386). The participants underwent a whole-body MRI examination. Hepatic fat content was quantified by proton-density fat fraction (PDFF). Aortic diameters in both studies and carotid plaque-related parameters in KORA were measured with MRI. In SHIP, carotid intima-media thickness (cIMT) and plaque were assessed by ultrasound. We used (ordered) logistic or linear regression to assess associations between hepatic fat and subclinical vascular disease.ResultsThe prevalence of fatty liver disease (FLD) (PDFF >5.6%) was 35% in SHIP and 43% in KORA. In SHIP, hepatic fat was positively associated with ascending (β, 95% CI 0.06 (0.04 to 0.08)), descending (0.05 (0.04 to 0.07)) and infrarenal (0.02 (0.01 to 0.03)) aortic diameters, as well as with higher odds of plaque presence (OR, 95% CI 1.22 (1.05 to 1.42)) and greater cIMT (β, 95% CI 0.01 (0.004 to 0.02)) in the age-adjusted and sex-adjusted model. However, further adjustment for additional cardiometabolic risk factors, particularly body mass index, attenuated these associations. In KORA, no significant associations were found.ConclusionsThe relation between hepatic fat and subclinical vascular disease was not independent of overall adiposity. Given the close relation of FLD with cardiometabolic risk factors, people with FLD should still be prioritised for cardiovascular disease screening.

Subclinical Vascular Disease in Children With Human Immunodeficiency Virus in Uganda Is Associated With Intestinal Barrier Dysfunction

Background The risk of cardiovascular disease (CVD) and its mechanisms in children living with perinatally acquired HIV (PHIV) in sub-Saharan Africa has been understudied. Methods Mean common carotid artery intima-media thickness (IMT) and pulse-wave velocity (PWV) were evaluated in 101 PHIV and 96 HIV-negative (HIV−) children. PHIV were on ART, with HIV-1 RNA levels ≤400 copies/mL. We measured plasma and cellular markers of monocyte activation, T-cell activation, oxidized lipids, and gut integrity. Results Overall median (interquartile range, Q1–Q3) age was 13 (11–15) years and 52% were females. Groups were similar by age, sex, and BMI. Median ART duration was 10 (8–11) years. PHIV had higher waist–hip ratio, triglycerides, and insulin resistance (P ≤ .03). Median IMT was slightly thicker in PHIVs than HIV− children (1.05 vs 1.02 mm for mean IMT and 1.25 vs 1.21 mm for max IMT; P < .05), while PWV did not differ between groups (P = .06). In univariate analyses, lower BMI and oxidized LDL, and higher waist–hip ratio, hsCRP, and zonulin correlated with thicker IMT in PHIV (P ≤ .05). After adjustment for age, BMI, sex, CD4 cell count, triglycerides, and separately adding sCD163, sCD14, and hsCRP, higher levels of intestinal permeability as measured by zonulin remained associated with IMT (β = 0.03 and 0.02, respectively; P ≤ .03). Conclusions Our study shows that African PHIV have evidence of CVD risk and structural vascular changes despite viral suppression. Intestinal intestinal barrier dysfunction may be involved in the pathogenesis of subclinical vascular disease in this population.

Human Vascular Pericytes and Cytomegalovirus Pathobiology

Pericytes are multipotent cells of the vascular system with cytoplasmic extensions proximal to endothelial cells that occur along the abluminal surface of the endothelium. The interactions between endothelial cells and pericytes are essential for proper microvascular formation, development, stabilization, and maintenance. Pericytes are essential for the regulation of paracellular flow between cells, transendothelial fluid transport, angiogenesis, and vascular immunosurveillance. They also influence the chemical composition of the surrounding microenvironment to protect endothelial cells from potential harm. Dysregulation or loss of pericyte function can result in microvascular instability and pathological consequences. Human pericytes have been shown to be targets for human cytomegalovirus (HCMV) infection and lytic replication that likely contribute to vascular inflammation. This review focuses on human vascular pericytes and their permissiveness for HCMV infection. It also discusses their implication in pathogenesis in the blood–brain barrier (BBB), the inner blood–retinal barrier (IBRB), the placenta–blood barrier, and the renal glomerulus as well as their potential role in subclinical vascular disease.