stigmasterol and Diabetes-Mellitus

Soybean oil consumption has increased greatly in the past half-century and is linked to obesity and diabetes. To test the hypothesis that soybean oil diet alters hypothalamic gene expression in conjunction with metabolic phenotype, we performed RNA sequencing analysis using male mice fed isocaloric, high-fat diets based on conventional soybean oil (high in linoleic acid, LA), a genetically modified, low-LA soybean oil (Plenish), and coconut oil (high in saturated fat, containing no LA). The 2 soybean oil diets had similar but nonidentical effects on the hypothalamic transcriptome, whereas the coconut oil diet had a negligible effect compared to a low-fat control diet. Dysregulated genes were associated with inflammation, neuroendocrine, neurochemical, and insulin signaling. Oxt was the only gene with metabolic, inflammation, and neurological relevance upregulated by both soybean oil diets compared to both control diets. Oxytocin immunoreactivity in the supraoptic and paraventricular nuclei of the hypothalamus was reduced, whereas plasma oxytocin and hypothalamic Oxt were increased. These central and peripheral effects of soybean oil diets were correlated with glucose intolerance but not body weight. Alterations in hypothalamic Oxt and plasma oxytocin were not observed in the coconut oil diet enriched in stigmasterol, a phytosterol found in soybean oil. We postulate that neither stigmasterol nor LA is responsible for effects of soybean oil diets on oxytocin and that Oxt messenger RNA levels could be associated with the diabetic state. Given the ubiquitous presence of soybean oil in the American diet, its observed effects on hypothalamic gene expression could have important public health ramifications.

Topics: Animals; Diabetes Mellitus; Gene Expression; Hypothalamus; Inflammation; Linoleic Acid; Male; Mice; Nervous System Diseases; Obesity; Oxytocin; Soybean Oil; Stigmasterol

Intravenous administration of the hexane extract of the bark of Anacardium occidentale (cashew) in normal, healthy dogs produced a significant lowering of the blood glucose levels. Pursuit of the hypoglycaemic principle(s) in the hexane extract resulted in the isolation and characterization of two compounds, stigmast-4-en-3-ol (1) and stigmast-4-en-3-one (2). These compounds were purified by chromatographic methods and the structures were characterized by spectroscopic methods. Both compounds produced significant hypoglycaemic activity after intravenous administration at a dose of 1.3 mg/kg body weight. The bark of the cashew plant, A. occidentale, exhibited a hypoglycaemic effect probably due to the presence of these compounds.

Topics: Anacardium; Animals; Diabetes Mellitus; Dogs; Female; Glucose Tolerance Test; Hypoglycemic Agents; Injections, Intravenous; Male; Phytotherapy; Plant Bark; Plant Extracts; Stigmasterol; Structure-Activity Relationship