Pancreatoprotective effects of Geniotrigona thoracica stingless bee honey in streptozotocin-nicotinamide-induced male diabetic rats

Stingless bee honey (SLBH) has been claimed to possess multiple health benefits. Its anti-diabetic properties are however unknown. In this study, ability of SLBH from Geniotrigona thoracica stingless bee species in ameliorating pancreatic damage and in maintaining metabolic profiles were investigated in diabetic condition. Methods: SLBH at 1 and 2 g/kg/b.w. was given orally to streptozotocin (STZ)-nicotinamide-induced male diabetic rats for 28 days. Metabolic parameters (fasting blood glucose-FBG and lipid profiles-LP and serum insulin) were measured by biochemical assays. Distribution and expression level of insulin, oxidative stress marker i.e. catalase, inflammatory markers i.e. IKK-beta, TNF-alpha, IL-1 beta and apoptosis marker i.e. caspase-9 in the pancreatic islets were identified and quantified respectively by immunohistochemistry. Levels of NF-k beta in pancreas were determined by enzyme-linked immunoassay (ELISA). Results: SLBH administration to diabetic male rats prevented increase in FBG, total cholesterols (TC), triglyceride (TG) and low density lipoprotein (LDL) levels. However, high density lipoprotein (HDL) and serum insulin levels in diabetic rats receiving SLBH increased. Additionally, histopathological changes and expression level of oxidative stress, inflammation and apoptosis markers in pancreatic islets of diabetic rats decreased with increased expression level of insulin in the islets. LC-MS analysis revealed the presence of several compounds in SLBH that might be responsible for these effects. Conclusions: SLBH has great potential to be used as agent to protect the pancreas against damage and dysfunction where these could account for its anti-diabetic properties. (C) 2017 Elsevier Masson SAS. All rights reserved.