This study investigated the antidiabetic activity of Salvia plebeia 70% ethanol extract (SPEE) and S. plebeia water extract (SPWE). The effects of SPEE and SPWE on adipogenesis were evaluated using 3T3-L1 adipocytes. Oil Red O staining showed that SPEE inhibited adipogenesis in 3T3-L1 adipocytes. Both SPEE and SPWE were analyzed for their total polyphenol contents (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities, and α-glucosidase inhibition. SPEE exhibited significantly higher TPC and DPPH radical-scavenging activities than SPWE. Next, an oral glucose tolerance test was performed to assess the potential hypoglycemic effects of SPEE in a streptozotocin (STZ)-induced diabetic mouse model. Blood glucose levels in STZ-induced diabetic mice decreased 30 min after treatment with SPEE (300 mg/kg) and SPWE (300 mg/kg). Therefore, this study provides a basis for further investigations into the clinical applications of SPEE as a preventative agent against diabetes.

The objective of the present study was to examine the effects of β-glucan originating from Aureobasidium on full-thickness skin wound healing in diabetic C57BL/KsJ-db/db mouse models. In the diabetic C57BL/KsJ-db/db model, test articles were topically applied twice a day for 20 days starting from 1 day after wounding. The results were compared to that of MadecassolTM ointment (madecassol; 1% Centella asiatica extracts) topically applied at a concentration of 100 mg/kg. Treatment with β-glucan resulted in significant (p<0.01 or p<0.05) and dose-dependent decreases in wound size compared with that of vehicle control showing increased wound size (WS, %). In addition, 50% contraction time (CT50) was dramatically and dose-dependently reduced, and inflammatory cells in granulation tissues of the wound area were significantly (p<0.01 or p<0.05) and dose-dependently reduced compared with that of vehicle control showing increased numbers of micro-vessels and fibroblasts as well as re-epithelialization. In the madecassol group, similar changes in inflammatory cells and fibroblasts with re-epithelialization were also observed, but madecassol did not influence angiogenesis. No meaningful changes in body weight were detected in all tested groups compared with the vehicle control. Therefore, these data suggest that β-glucan has a beneficial effect on diabetic delayed skin wound healing and may be useful to manage incurable skin wounds in diabetic animals.