Glucocorticoids associate with cardiometabolic risk factors in black South Africans

Abstract

Circulating glucocorticoids are associated with the metabolic syndrome and related cardiometabolic risk factors in non-Africans. This study investigated these associations in Africans, whose metabolic phenotype reportedly differs from Europeans. Measures of adiposity, blood pressure, glycaemia, insulin resistance, and lipid profile, were measured in 316 African men and 788 African women living in Soweto, Johannesburg. The 2009 harmonized criteria were used to define the metabolic syndrome. Serum glucocorticoids were measured using liquid chromatography-mass spectrometry. Cortisol was associated with greater odds of presenting with the metabolic syndrome (odds ratio (95% confidence interval, 95%CI) =1.50 [1.04, 2.17] and higher systolic (beta coefficient, β (95%CI) =0.04 [0.01, 0.08]) and diastolic (0.05 [0.02, 0.09]) blood pressure, but higher HDL (0.10 [0.02, 0.19]) and lower LDL (-0.14 [-0.24, -0.03]) cholesterol concentrations, in the combined sample of men and women. In contrast, corticosterone was only associated with higher insulin sensitivity (Matsuda index; 0.22 [0.03, 0.41]), but this was not independent of BMI. Sex-specific associations were observed, such that both cortisol and corticosterone were associated with higher fasting glucose (standardized β (95%CI): 0.24 [0.12, 0.36] for cortisol; and 0.12 [0.01, 0.23] for corticosterone) and HbA1c (0.13 [0.01, 0.25] for cortisol; and 0.12 [0.01, 0.24] for corticosterone) in men only, but lower HbA1c (0.10 [ -0.20, -0.01] for cortisol; and -0.09 [-0.18, -0.03] for corticosterone) in women only. Our study reports for the first time that associations between circulating glucocorticoid concentrations and key cardiometabolic risk factors exhibit both glucocorticoid- and sex-specificity in Africans.

Targeted proteomics of appendicular skeletal muscle mass and handgrip strength in black South Africans: a cross-sectional study

“…Moreover, the German study did not adjust for adiposity in their analyses, possibly because adiposity measures were correlated with one of their outcomes (body fat mass index). Hence, many biomarkers were likely missed by not adjusting for adiposity, which is a well-known confounder in complex diseases 20 . Consistent with the confounding effects of adiposity, in the German study, the direction of association between some of the biomarkers (LEP, THBS2 and GDF-2) and ASM changed when body fat mass was included in the statistical models 19 .…”

“…A recent study from Germany used proximity extension assay-measured proteomics to investigate circulating biomarkers of low ASM and high fat mass in 756 men and 722 women of European ancestry, and although they identified novel circulating biomarkers associated with ASM, they did not explore sex-specific associations 19 . While sex-interactions in complex diseases are often not explored, accumulating evidence suggests that they play a key role in determining disease risk in humans 20 . The primary aim of this study was to investigate associations of circulating biomarkers with ASM and HGS in middle-aged black South Africans.…”

Investigation of Behavior and Plasma Levels of Corticosterone in Restrictive- and Ad Libitum-Fed Diet-Induced Obese Mice

“…[58,59]. Nevertheless, it is important to investigate corticosterone in DIO mice models since it is well-known that corticosterone influences the fat distribution, the development of obesity, the metabolic syndrome, cardiovascular diseases, and probably also psychiatric disorders in humans [15,60,61].…”