Dietary resistant maltodextrin ameliorates testicular function and spermatogenesis in streptozotocin-nicotinamide-induced diabetic rats

This study investigated the effect of resistant maltodextrin (RMD) on reproduction in streptozotocin (STZ)-nicotinamide-induced type 2 diabetic male rats. Forty male rats were induced with diabetes by a single intraperitoneal injection of STZ (50 mg kg^-1) and nicotinamide (100 mg kg^-1). Five groups were analysed in total: normal, diabetic rats without RMD, diabetic rats with RMD 1.2 g per 100 g diet (1×), with RMD 2.4 g per 100 g (2×), and with RMD 6.0 g per 100 g (5×). The groups of diabetic rats with the RMD supplement, compared to those without supplement, showed improved plasma glucose control, attenuated insulin resistance and recovery of testosterone level and spermatogenesis stage. The STZ-nicotinamide-induced diabetes mellitus (DM) caused a significant reduction in serum testosterone, testis androgen receptor (AR), steroidogenic acute regulatory protein (StAR) and 3β-hydroxysteroid dehydrogenase (3β-HSD) protein, but a statistical recovery in each of these was observed in the 5× group. TUNEL-positive cells were observed in the diabetic without RMD group, and RMD treatment reduced apoptotic germ cells. The expression of Bax/Bcl2 was induced in the diabetic group and also significantly reduced in the 5× group. Dietary RMD may improve metabolic control in STZ-nicotinamide-induced diabetic rats and attenuate hyperglycaemia-related impaired male reproduction and testicular function.