The prevalence of type 2 diabetes mellitus (T2DM) has increased considerably in recent years, highlighting the importance of developing new therapeutic strategies. Insulin-resistance and gradual dysfunction of pancreatic islets are the mainstay in the progression of T2DM. Therefore, preserving the function of the pancreas may lead to new prospective approaches. Our previous studies suggested that grape seed procyanidin B2 (GSPB2), a natural polyphenol product, exhibited protective effects on diabetic vasculopathy. However, effects of GSPB2 on a diabetic pancreas remain unknown. In this study, we provided strong evidence that GSPB2 exerted protective effects on a diabetic pancreas. GSPB2 attenuated the elevated body weights, food intake and advanced glycation end-product (AGE) levels in db/db mice (p < 0.05), though it had no significant effect on glucose levels. The increased islet sizes, insulin levels, as well as HOMA-IR were also improved by GSPB2 treatment in db/db mice (p < 0.05). Milk fat globule epidermal growth factor-8 (MFG-E8), an estimated target of GSPB2 in our previous studies, was up-regulated in pancreatic tissues whereas GSPB2 treatment down-regulated the protein level (p < 0.05). Since MFG-E8 is highly involved in inflammation, we further investigate pro-inflammatory cytokines interleukin-1β (IL-1β) and NLRP3 levels. We found that levels of IL-1β and NLRP3 increased in a diabetic pancreas while GSPB2 treatment notably attenuated these alterations (p < 0.05). In conclusion, our results suggest that inflammation is involved in the damage of a diabetic pancreas and GSPB2 provides protective effects at least in part through anti-inflammation.

Vitamin D deficiency is implicated in some diseases, including cardiovascular. Few studies have assessed the correlation between 25-hydroxyvitamin D3 [25(OH) D3] and serum lipids. In this study, we explored the correlation between serum 25(OH) D3 concentrations and serum lipids with a typical sample of the rural population in China. Face-to-face research was used to gather some basic information. Fasting serum concentrations of 25-(OH) D3, total cholesterol (TC), triglyceride (TG), HDL cholesterol (HDL-C) and, LDL cholesterol (LDL-C) tested in the laboratory. The mean of serum 25(OH) D3 level was 28.71 ± 29.29 ng/mL. The results showed that the dyslipidemia was strongly associated with gender (P = 0.031), drinking (P = 0.043), high-fat diet intake (P = 0.017), HDL-C (P<0), TG (P<0), body mass index (BMI) (P<0) and serum 25(OH)D3 levels (P = 0.002). There was a positive correlation between serum 25(OH)D3 and HDL-C (P<0) in all groups. The relationship between 25(OH) D3 and LDL-C (P = 0.024) was discovered only in normal lipid group. The multivariable adjusted odds ratio (95%CI) of hypoalphalipoproteinemia/HDL and dyslipidemia by comparing the sufficiency vs. the deficiency serum 25-(OH) D3 level were 0.31 (0.192, 0.499) (P = 0.001) and 0.52 (0.36, 0.73) (P = 0.005), respectively. Serum 25(OH) D3 concentrations were associated with the serum lipids level and the association was different in normal serum lipid group and dyslipidemia group. With the increase of serum 25(OH) D3 levels, the incidence of dyslipidemia decreased.