Antiobesogênico, hipocolesterolêmico e antioxidante efeitos da botriosferana, uma β(1→3)(1→6)-D-glucana, em ratas

Abstract

Botryosphaeran is a β-(1→3)(1→6)-D-glucan produced by the ascomycete fungus Botryosphaeria rhodina MAMB-05. Studies have demonstrated the efficacy of botryosphaeran in reducing obesity, hepatic steatosis, correcting dyslipidemia, insulin resistance, and glucose intolerance in obese male rats, as well as showing antitumor effects both in vitro (MCF-7 breast cancer cells) and in vivo (male Wistar rats). However, studies conducted with female rats are still scarce. Therefore, the aim of this study was to evaluate the effects of botryosphaeran in obese and non-obese female rats, assessing its metabolic and antioxidant effects. For this purpose, female Wistar rats (n=32) were divided into four groups: control (C), control botryosphaeran (CB), obese (O), and obese botryosphaeran (OB), over an 8-week period, with obesity induced by a high-fat, high-carbohydrate diet. From the 6th to the 8th week, the CB and OB rats received treatment with botryosphaeran (12 mg/kg/day via gavage), while the C and O rats received water also via gavage. At the end of this period, anthropometric analyses, food intake, glucose tolerance, insulin tolerance, biochemical assays, and evaluation of pro- and antioxidant markers were performed. The study was approved by the CEUA (protocol Nº. 23108.072920/2023-21). It was observed that obese rats exhibited fat accumulation, hepatomegaly, dyslipidemia, insulin resistance, glucose intolerance, and oxidative stress, well characterizing the model of obesity induced by a high-fat, high-carbohydrate diet. Botryosphaeran significantly reduced the body weight of both control and obese rats and markedly reduced the amount of retroperitoneal fat in obese rats. Additionally, botryosphaeran corrected glucose intolerance and dyslipidemia in OB rats, improving pancreatic response to glucose overload and significantly reducing triglyceride, total cholesterol, LDL-, and VLDL cholesterol levels. Botryosphaeran also exhibited antioxidant effects in various tissues such as the liver, muscles, and kidneys, reducing TBARS levels and increasing vitamin C levels. Thus, it can be concluded that botryosphaeran presents an important and significant anti-obesogenic, hypocholesterolemic, insulin-sensitizing, and antioxidant effect, being a potential drug for the treatment of obesity and its comorbidities.