Abstract
Elevated intra-tissue levels of active glucocorticoids in obese patients are associated with insulin resistance, diabetes, impaired immune regulation, and other adverse effects. Sleeve gastrectomy (SG) induces significant weight loss and improves metabolic outcomes, including insulin resistance and hyperlipidemia. Among the enzymes controlling intracellular concentrations of active glucocorticoids, 11β-hydroxysteroid dehydrogenase type 1 (HSD11B1, SDR26C1) has been extensively studied concerning obesity and post-gastric surgery interventions. However, most studies focused on either a single tissue, circulating glucocorticoid levels, or HSD11B1 activity. In this work, we showed that circulating active/inactive glucocorticoid ratio (corticosterone (B)/11-dehydrocorticosterone (A)) negatively correlated with glucose tolerance; SG in male C57BL/6 mice slightly reduced circulating mineralocorticoids and reversed the elevated ratio of B/A seen in sham-operated mice after high-fat diet, while improving glucose tolerance. This change was likely due to increased renal 11β-hydroxysteroid dehydrogenase type 2 (HSD11B2, SDR9C3) activity after SG. To provide a comprehensive overview of the systemic effects post-surgery, we evaluated enzymes involved in glucocorticoid homeostasis across tissues on mRNA, protein, and activity level. Moreover, mRNA expression of transcription factors CCAAT enhancer binding protein alpha (Cebpa), Cebpb and nuclear factor kappa b (Nfκb (p50)), as well as cytokines influencing Hsd11b1 and Hsd11b2 gene expression were analyzed. The results emphasize stronger influence of renal HSD11B2 than hepatic HSD11B1 activity on the circulating B/A ratio, supported by intrarenal and intrahepatic B/A ratios. The improved glucocorticoid homeostasis following SG, indicated by decreased B/A ratios, proposes a lower risk for glucocorticoid-mediated adverse health effects, including chronic kidney disease, hypertension, and metabolic disturbances.