Botryosphaeran reduces obesity, hepatic steatosis, dyslipidaemia, insulin resistance and glucose intolerance in diet-induced obese rats

• Published in: Life sciences (1973) Vol. 211; pp. 147 - 156
• Main Authors: Silva, Amadeu Z., Costa, Felipe P.L., Souza, Ingrid L., Ribeiro, Mariana C., Giordani, Morenna Alana, Queiroz, Diogo A., Luvizotto, Renata A.M., Nascimento, André F., Bomfim, Gisele F., Sugizaki, Mario M., Dekker, Robert F.H., Barbosa-Dekker, Aneli M., Queiroz, Eveline A.I.F.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 15-10-2018; Elsevier BV
• Subjects: (1 → 3)(1 → 6)-β-D-Glucan; Adipose tissue; AMP; AMP-activated protein kinase; AMPK; Animals; Blood Glucose - analysis; Body weight gain; Botryosphaeria rhodina MAMB-05; Cholesterol; Diabetes mellitus; Diet; Diet, High-Fat - adverse effects; Dyslipidemia; Dyslipidemias - etiology; Dyslipidemias - pathology; Dyslipidemias - prevention & control; Fatty liver; Fatty Liver - etiology; Fatty Liver - pathology; Fatty Liver - prevention & control; Forkhead protein; FOXO3 protein; FOXO3a; Glucan; Glucans; Glucans - pharmacology; Glucose; Glucose Intolerance - etiology; Glucose Intolerance - pathology; Glucose Intolerance - prevention & control; Glucose tolerance; Glycogen; High density lipoprotein; High fat diet; Ingestion; Insulin; Insulin Resistance; Intolerance; Kidney diseases; Lipids; Lipoproteins (very low density); Liver; Male; Obesity; Obesity - etiology; Obesity - pathology; Obesity - prevention & control; Pathogens; Proteins; Rats; Rats, Wistar; Rodents; Steatosis; Sucrose; Sugar; Triglycerides; Western blotting; β-Glucan; (1 → 3)(1 → 6)-β-D-Glucan; AMPK; FOXO3a; Botryosphaeria rhodina MAMB-05
• ISSN: 0024-3205; 1879-0631
• DOI: 10.1016/j.lfs.2018.09.027

Obesity is associated with comorbidities such as diabetes and hepatic steatosis. β-Glucans have been described as effective in treating conditions including dyslipidaemia and diabetes. Thus, the objective of this study was to evaluate the effects of botryosphaeran [(1 → 3)(1 → 6)-β-D-glucan] on obesity and its comorbidities, and understand its mechanism of action.
Obesity was induced in adult male Wistar rats by ingestion of a high-fat diet and water with sucrose (300 g/L) for 8 weeks. Control rats received standard diet. After six weeks, treatment commenced with botryosphaeran (12 mg/kg.b.w., via gavage, 15 days), respective controls received water. Rats were divided into 3 groups: control (C), obese (O), and obese + botryosphaeran (OB). In the 8th week, obesity was characterized. Feed-intake, glucose and lipid profiles, glucose tolerance, and concentrations of glycogen and lipids in liver were analyzed. Protein expression was determined by Western blotting.
Obese rats showed significant increases in weight gain and adipose tissue, presented glucose intolerance, dyslipidaemia, and hepatic steatosis. Botryosphaeran significantly reduced feed intake, weight gain, periepididymal and mesenteric fat, and improved glucose tolerance. Botryosphaeran also reduced triglyceride and VLDL, and increased HDL levels. Furthermore, botryosphaeran increased glycogen and reduced total lipids, triglycerides and cholesterol in liver, and increased AMP-activated protein kinase(AMPK) activity and Forkhead transcription factor 3a(FOXO3a) protein expression in adipose tissue.
This study demonstrated that botryosphaeran was effective in reducing obesity, hepatic steatosis, dyslipidaemia insulin resistance and glucose intolerance in diet-induced obese rats, and these effects were, at least in part, associated with reduced feed intake, and AMPK and FOXO3a activities.