The protective effect of sulforaphane on type II diabetes induced by high-fat diet and low-dosage streptozotocin.

Sulforaphane (SFN) which is abundant in broccoli florets, seeds, and sprouts has been reported to have beneficial effects on attenuating metabolic diseases, such as antiobesity, antidiabetes, and antioxidative activities. However, the effects of SFN on the regulation of type II diabetes through easing nonalcoholic fatty liver (NAFLD) and repairing pancreas tissue are rarely reported. In this study, we found that the administration with different dosages of SFN was able to increase serum insulin level, enhance HOMA-β index, decrease fasting blood glucose and serum total cholesterol, triglyceride, low-density lipoprotein (LDL-C), fibroblast growth factor21 (FGF21) levels, ease NAFLD level, and repair the pancreas tissue. In addition, SFN was able to increase liver antioxidant capacities. In particular, high (10 mg/kg) dosage of SFN exerted a significant beneficial effect for decreasing serum lipopolysaccharide levels. Furthermore, the administration of SFN could also decrease the relative abundance of Allobaculum at the genus level. Low dosage (2 mg/kg) of SFN could increase the relative abundance of Bacteroidetes and decrease the relative abundance of Firmicutes at the phylum level. Overall, our results showed that SFN exerted its antidiabetic effect through easing NAFLD and repairing pancreas tissue in association with modulation of gut microbiota. The ease of NAFLD by SFN was accompanied by enhancing liver antioxidant abilities and improving FGF21 resistance.