Miras, A. D. | Search bioRxiv

bioRxiv2026

Vertical Sleeve Gastrectomy inhibits 11βHSD1 and subsequently reduces IL6 secretion in Mice and Humans: A Shared Anti-Inflammatory Mechanism

BackgroundVertical sleeve gastrectomy (VSG) improves glycaemic control in type 2 diabetes (T2D) through mechanisms that extend beyond weight loss. The interaction between glucocorticoid metabolism and inflammation in this context remains unclear. MethodsWe investigated the role of 11{beta}-hydroxysteroid dehydrogenase type 1 (11{beta}HSD1) in mediating the metabolic effects of VSG in humans and mice. Subcutaneous adipose tissue biopsies were collected before and 6 months after VSG. Parallel studies were conducted in lean and high-fat diet-fed mice undergoing VSG or sham surgery, alongside 11{beta}HSD1 knockout models. Glucose tolerance and expression of 11{beta}HSD1 and interleukin-6 (IL6) were assessed. Mechanistic interactions were examined in IL6-treated human hepatocytes. ResultsVSG reduced 11{beta}HSD1 and IL6 expression in human adipose tissue and improved insulin resistance. In lean mice, VSG improved glucose tolerance and downregulated both markers independently of weight loss. 11{beta}HSD1 knockout mice exhibited improved glucose tolerance despite increased adiposity, partially recapitulating the VSG phenotype. Both interventions reduced circulating and tissue IL6 levels. IL6 stimulation increased HSD11B1 expression in hepatocytes. Conclusions11{beta}HSD1 links glucocorticoid metabolism, inflammation, and glucose homeostasis following VSG. Targeting this pathway may offer a strategy to replicate key metabolic benefits of metabolic bariatric surgery.

physiology↗

bioRxiv2025

α-Melanocyte Stimulating Hormone Reduces Blood Glucose Across Species

Peripheral administration of -melanocyte stimulating hormone (-MSH) promotes glucose uptake in skeletal muscle via a melanocortin 5 receptor (MC5R)-dependent mechanism in rodents. Here we demonstrate that this pathway is functional in humans. During an oral glucose tolerance test (GTT) in healthy human volunteers, peripheral administration of -MSH was well tolerated, and reduced glucose and insulin incremental area under the curve by 39% and 35%, respectively. During a GTT in non-human primates, both -MSH and a selective MC5R agonist, PG-901, increased glucose tolerance. In vitro, both -MSH and PG-901 induced glucose uptake in primary human and non-human primate myotubes and immortalised human myotubes. Subcutaneous injection of PG-901 reduced blood glucose concentrations during a GTT in WT mice but had no effect in MC5R deficient mice. Thus, the novel MC5R-skeletal muscle pathway found in animals is functional in humans and represents a novel target for glycaemic control in people with diabetes.

physiology↗