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Objectives: To examine the relationship between pericardial fat (PCF) and cardiac structure and function among HIV-infected patients in the sub-Saharan African country of Uganda. People living with HIV (PLHIV) have altered fat distribution and an elevated risk for heart failure. Whether altered quantity and radiodensity of fat surrounding the heart relates to cardiac dysfunction in this population is unknown.Methods: One hundred HIV-positive Ugandans on antiretroviral therapy were compared with 100 age and sex-matched HIV-negative Ugandans; all were >45 years old with >1 cardiovascular disease risk factor. Subjects underwent ECG-gated non-contrast cardiac CT and transthoracic echocardiography with speckle tracking strain imaging. Multivariable linear and logistic regression models were used to explore the association of PCF with echocardiographic outcomes.Results: Median age was 55% and 62% were female. Compared with uninfected controls, PLHIV had lower body mass index (27 vs 30, p=0.02) and less diabetes (26% vs 45%, p=0.005). Median left ventricular (LV) ejection fraction was 67%. In models adjusted for traditional risk factors, HIV was associated with 10.3 g/m2 higher LV mass index (LVMI) (95% CI 3.22 to 17.4; p=0.005), 0.87% worse LV global longitudinal strain (GLS) (95% CI -1.66 to -0.07; p=0.03) and higher odds of diastolic dysfunction (OR 1.96; 95% CI 0.95 to 4.06; p=0.07). In adjusted models, PCF volume was significantly associated with increased LVMI and worse LV GLS, while PCF radiodensity was associated with worse LV GLS (all p<0.05).Conclusions: In Uganda, HIV infection, PCF volume and density are associated with abnormal cardiac structure and function. [ABSTRACT FROM AUTHOR]

Protein kinases AKT and PKBR1 of Dictyostelium belong to the AGC protein kinase superfamily. AKT and PKBR1 are phosphorylated at similar sites by phosphoinositide-dependent kinase 1 (PDK1) and TORC2 kinases; however, they have different subcellular localizing domains. AKT has a phosphoinositide 3-kinase (PI3K)/phosphatidylinositol (3,4,5)-trisphosphate [PtdIns(3,4,5)P3]-regulated PH (pleckstrin homology) domain whereas PKBR1 is myristoylated and persistently membrane localized. Using strains defective for PI3K/PtdIns(3,4,5)P3-, PDK1- and TORC2-signaling or strains that express phospho-site mutants of AKT and PKBR1, we dissect the different roles of PI3K/PtdIns(3,4,5)P3, PDK1 and TORC2. We show that activation of AKT and PKBR1 requires PDK1-site phosphorylation, but that phosphorylation by TORC2 is insufficient for AKT or PKBR1 activation. However, PDK1-site phosphorylation is dependent on phosphorylation by TORC2, which suggests that there is regulatory coordination among PDK1, TORC2 and their phospho-site targets. This defines a separate input for signaling in control of chemotaxis and dependency on PDK1 function. We also demonstrate that PDK1 in Dictyostelium functions independently of PI3K/PtdIns(3,4,5)P3. Finally, we show that AKT and PKBR1 exhibit substrate selectivity and identify two novel lipid-interacting proteins preferentially phosphorylated by AKT. Despite certain similarities, AKT and PKBR1 have distinct regulatory paths that impact activation and effector targeting, with PDK1 serving a central role. [ABSTRACT FROM AUTHOR]

Background: People with HIV (PWH) are at an increased risk of both heart and kidney disease, but the relationship between kidney disease and cardiac structure and function in this population has not been well studied. In particular, whether the relationship between kidney disease and cardiac structure and function is stronger for PWH compared with uninfected controls is unknown., Methods: One hundred PWH on antiretroviral therapy were compared with 100 age-matched and sex-matched controls without HIV in Uganda. Multivariable regression models were used to examine associations between creatinine-based and cystatin C-based estimated glomerular filtration rate (eGFR), albumin-creatinine ratio, and echocardiographic measures of cardiac structure and function., Results: PWH had lower eGFRcr (β -7.486, 95% confidence interval: -13.868 to -1.104, P = 0.022) and a higher rate of albumin-creatinine ratio ≥30 (odds ratio 2.146, 95% confidence interval: 1.027 to 4.484, P = 0.042) after adjustment for traditional risk factors. eGFR was inversely associated with both left ventricular mass index and diastolic dysfunction in adjusted models but not with systolic function. Albuminuria was associated with more diastolic dysfunction among PWH but not controls (P for interaction = 0.046). The association of HIV with a higher left ventricular mass index (P = 0.005) was not substantially affected by adjusting for eGFRcr., Conclusion: Among Ugandans, eGFR is associated with elevated LV mass and diastolic dysfunction. The association between albuminuria and diastolic dysfunction is particularly strong for PWH.