stigmasterol and Obesity

Edible Brown Seaweed Sargassum fusiforme (Harvey) Setchell, 1931 abbreviated as Sargassum fusiforme was used for folk medical therapy in East Asia countries over five hundred years. Saringosterol acetate (SA) was isolated from S. fusiforme in our previous study and indicated various effects. However, anti-obesity activity of SA and its mechanism still unknown.. The inhibitory effect of SA, isolated from S. fusiforme, on adipogenesis in 3T3-L1 adipocytes was investigated in vitro and in zebrafish model. Cell toxicity, differentiation, signaling pathway, and lipid accumulation of SA treated 3T3-L1 adipocytes were determined. The body weight and triglyceride content of diet-induced obese (DIO) adult male zebrafish were measured from 12 to 17 weeks after fertilization.. SA attenuated the differentiation of cells and reduced lipid accumulation, and triglyceride content in the 3T3-L1 adipocytes. During the differentiation of adipocytes, SA suppressed fat accumulation and decreased the expression of signal factors responsible for adipogenesis. In SA-treated adipocytes, while fatty acid synthetase was downregulated, AMP-activated protein kinase (AMPK) was upregulated. Furthermore, SA suppressed body weight and triglyceride content in DIO zebrafish.. SA is a potential therapeutic agent in the management of metabolic disorders, such as obesity.

Topics: 3T3-L1 Cells; Acetates; Adipogenesis; AMP-Activated Protein Kinases; Animals; Body Weight; Diet, High-Fat; Fatty Acid Synthases; Male; Mice; Obesity; Stigmasterol; Triglycerides; Zebrafish

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

The purpose of this study was to investigate the effects of fucosterol on adipogenesis of 3T3-L1 preadipocytes and its underlying mechanisms.. Fucosterol, isolated from brown algae, Ecklonia stolonifera. We investigated the levels of lipid accumulation using Oil Red O staining. We conducted Western blot analysis to investigate regulatory effects of fucosterol on expression of phosphoinositide 3-kinase (PI3K), Akt, extracellular signal-regulated kinase (ERK), forkhead box protein O 1 (FoxO1) in 3T3-L1 adipocytes.. Fucosterol significantly reduced intracellular lipid accumulation of 3T3-L1 adipocytes at concentrations of 25 and 50 μm. Fucosterol downregulated insulin-triggered PI3K/Akt, and ERK pathways. It subsequently decreased expression of adipogenic transcription factors, including PPARγ, C/EBPα and SREBP-1. In addition, fucosterol enhanced SirT1 expression while decreased phospho-FoxO1 expression which resulted in the activation of FoxO1.. We revealed that fucosterol inhibited adipogenesis of 3T3-L1 preadipocytes through modulation of FoxO signalling pathway. Therefore, our results suggest that fucosterol may be used for novel agents for the treatment of obesity.

Topics: 3T3-L1 Cells; Adipocytes; Adipogenesis; Animals; Anti-Obesity Agents; CCAAT-Enhancer-Binding Protein-alpha; Cell Line; Down-Regulation; Extracellular Signal-Regulated MAP Kinases; Forkhead Box Protein O1; Lipid Metabolism; Mice; Obesity; Phaeophyceae; Phosphatidylinositol 3-Kinases; Plant Extracts; PPAR gamma; Proto-Oncogene Proteins c-akt; Signal Transduction; Stigmasterol

Obesity is associated with increased systemic and airway oxidative stress, which may result from a combination of adipokine imbalance and antioxidant defenses reduction. Obesity-mediated oxidative stress plays an important role in the pathogenesis of dyslipidemia, vascular disease, and nonalcoholic hepatic steatosis. The antidyslipidemic activity of pigeon pea were evaluated by high-fat diet (HFD) hamsters model, in which the level of high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), total cholesterol (TC), and total triglyceride (TG) were examined. We found that pigeon pea administration promoted cholesterol converting to bile acid in HFD-induced hamsters, thereby exerting hypolipidemic activity. In the statistical results, pigeon pea significantly increased hepatic carnitine palmitoyltransferase-1 (CPT-1), LDL receptor, and cholesterol 7α-hydroxylase (also known as cytochrome P450 7A1, CYP7A1) expression to attenuate dyslipidemia in HFD-fed hamsters; and markedly elevated antioxidant enzymes in the liver of HFD-induced hamsters, further alleviating lipid peroxidation. These effects may attribute to pigeon pea contained large of unsaturated fatty acids (UFA; C18:2) and phytosterol (β-sitosterol, campesterol, and stigmasterol). Moreover, the effects of pigeon pea on dyslipidemia were greater than β-sitosterol administration (4%), suggesting that phytosterone in pigeon pea could prevent metabolic syndrome.

Topics: Animals; Antioxidants; Cajanus; Carnitine O-Palmitoyltransferase; Cholesterol; Cholesterol 7-alpha-Hydroxylase; Cholesterol, HDL; Cholesterol, LDL; Chromatography, High Pressure Liquid; Cricetinae; Diet, High-Fat; Disease Models, Animal; Hypercholesterolemia; Lipid Peroxidation; Liver; Male; Obesity; Oxidative Stress; Phytosterols; Receptors, LDL; Sitosterols; Stigmasterol; Triglycerides