Anti-diabetic activities of Kocat-D1 in 3T3-L1 adipocytes and C57BL/KsJ-db/db mice

This study investigated anti-diabetic activity of Kocat-D1, which is a currently used traditional medicine for treatment of diabetes in Shandong, China. Insulin sensitizing activity was observed in a cell-based glucose uptake assay using 3T3-L1 adipocytes. The treatment of 0.2 mg/mL of hot water extract of Kocat-D1 with 0.2 nM insulin was associated with a significant increasing in glucose uptake (165.0±0.7%) over the treatment of 0.2 nM insulin. C57BL/KsJ-db/db mice (8 weeks of age) were separated into 3 groups: normal control (control, db/ mice untreated), diabetic control (DM control, db/db mice untreated), Kocat-D1 (db/db mice treated with Kocat-D1 extract 350 mg/kg/day). After 16 weeks of treatment, body weight and total diet intake of Kocat-D1 group were significantly lower than DM control groups. Blood glucose levels of the Kocat-D1 group (14.7±1.4 mmol/L) were significantly lower compared to the DM control group (27.1±0.2 mmol/L). Furthermore, insulin level was significantly increased in the Kocat-D1 group (0.17±0.02 ng/mL) compared with the DM control group (0.05±0.02 ng/mL). The glomeruli in kidney was stained using periodic acid-shiff base (PAS) for confirming collagen accumulation. The glomeruli in kidney of Kocat-D1 group had significantly reduced PAS-positive compared with that of DM control.