bixin and Obesity

Associations between obesity, diabetes type II, and steatosis have long been recognized. However, a pharmacotherapy that acts in a multifactorial manner controlling the interactions between these conditions is not available. A variety of natural plants, functional fatty acids, and other natural dietary compounds have been used in various anti-obesity products. We investigated the effects of oral administration of an antioxidant carotenoid pigment Bixin and Bixin: β-Cyclodextrin in an obese murine model. C57BL/6 male mice (4-5 weeks) received standard diet (2.18 kcal per 1 g) (CT) and high-fat diet (4.38 kcal per 1 g) (CT/OB, BIX and BIX/βCD) (n = 10 per group). After 16 weeks, the BIX and BIX/βCD were treated by gavage (100 μL day-1) for six weeks, with water (CT and CT/OB groups) and (50 mg kg-1 day-1), Bixin (BIX group) or Bix: β-CD (BIX/βCD). Body weight, Lee's Index, adiposity, CHT, TG, CHT/HDL-c, glucose levels (metabolic markers) and, liver markers (AST and ALT) were determined. All metabolic and liver parameters exhibited down-regulation after oral administration of BIX and BIX/βCD. Particularly relevant was Lee's Index and adiposity in BIX- and BIX/βCD-treated groups (339.18 g/cm -BIX and 327.58 g/cm -BIX/βCD vs. 360.68 g/cm -CT/OB animals), this finds associated with the insulin sensitivity test, showed a clear association between reduction of adipose tissue and decrease of peripherical insulin resistant. In conclusion, our study suggested that the oral administration of the Bixin and Bix: β-CD inclusion compound improved the metabolic parameters evaluate in obese mice, being more palatable and hepatoprotective.

Topics: 3T3-L1 Cells; Adipocytes; Adiposity; Animals; beta-Cyclodextrins; Biomarkers; Blood Glucose; Carotenoids; Diet, High-Fat; Disease Models, Animal; Dose-Response Relationship, Drug; Fatty Liver; Glucose Metabolism Disorders; Hypoglycemic Agents; Hypolipidemic Agents; Lipids; Liver; Male; Mice; Mice, Inbred C57BL; Obesity; Time Factors

Peroxisome proliferator-activated receptor α (PPARα) is a ligand-activated transcription factor that regulates the expression of the genes involved in fatty acid oxidation. PPARα activators induce fatty acid oxidation in the liver, thereby improving lipid and carbohydrate metabolism in obese mice. In this study, the dietary cis-carotenoids bixin and norbixin, which are commonly used in the food coloring industry, were found to activate PPARα by luciferase reporter assays using GAL4/PPARα chimeric and full-length PPARα systems. Treatment with bixin and norbixin induced the mRNA expression of PPARα target genes involved in fatty acid oxidation in PPARα-expressing HepG2 hepatocytes. In obese KK-Ay mice, bixin treatment suppressed the development of hyperlipidemia and hepatic lipid accumulation. In the livers of bixin-treated mice, the mRNA levels of PPARα target genes related to fatty acid oxidation were up-regulated. Moreover, bixin treatment also improved obesity-induced dysfunctions of carbohydrate metabolism, such as hyperglycemia, hyperinsulinemia, and hypoadiponectinemia. Glucose tolerance test and insulin tolerance test revealed that glucose intolerance and insulin resistance in KK-Ay obese mice were attenuated by the treatment with bixin. These results indicate that bixin acts as a food-derived agonist of PPARα, and bixin treatment is useful for the management of obesity-induced metabolic dysfunctions in mice.

Topics: Adiponectin; Animals; Carbohydrate Metabolism; Carotenoids; Diet, High-Fat; Fatty Liver; Gene Expression Regulation; Glucose Tolerance Test; Hepatocytes; Hyperlipidemias; Lipid Metabolism; Male; Mice; Mice, Obese; Obesity; PPAR alpha