Sodium butyrate reduces insulin-resistance, fat accumulation and dyslipidemia in type-2 diabetic rat: A comparative study with metformin

• NaB treatment significantly reduces plasma glucose, HbA1c and insulin-resistance.
• NaB treatment reduces fat accumulation in WAT, BAT and steatosis in liver.
• NaB treatment inhibits total HDAC activity and increases histone H3 acetylation.
• NaB treatment inhibits the gluconeogenesis and improves glucose homeostasis.

Recent evidences highlighted that histone deacetylases (HDACs) can deacetylate the histone, various transcription factors and regulatory proteins, which directly or indirectly affect glucose metabolism. The present study aimed to evaluate the comparative effects of sodium butyrate (NaB) and metformin on the glucose homeostasis, insulin-resistance, fat accumulation and dyslipidemia in type-2 diabetic rat. Diabetes was developed in Sprague-Dawley rats by the combination of high-fat diet (HFD) and low dose streptozotocin (STZ, 35 mg/kg). NaB at the doses of 200 and 400 mg/kg twice daily as well as metformin (as a positive control) 150 mg/kg twice daily for 10 consecutive weeks were administered by i.p. and oral route, respectively. NaB treatment significantly reduced the plasma glucose, HbA1c, insulin-resistance, dyslipidemia and gluconeogenesis, which are comparable to metformin treatment. Further, NaB treatment ameliorated the micro- and macro-vesicular steatosis in liver and fat deposition in brown adipose tissue, white adipose tissue (adipocytes hypertrophy) as well as pancreatic beta-cell damage. In the present study, both NaB and metformin inhibited the diabetes-associated increased HDACs activity, thereby increased the acetylation of histone H3 in liver. The present findings demonstrated that NaB and metformin reduced insulin-resistance, dyslipidemia, fat accumulation and gluconeogenesis thereby improved the glucose homeostasis in rat. Thus, NaB might be a promising molecule for the prevention and treatment of type-2 diabetes and dyslipidemia.