Effect of gamma conglutin treatment on JNK1 gene expression and protein activation in a rat model of type 2 diabetes.

Context: Gamma conglutin (Cγ) from lupine species represents a potential complementary treatment for type 2 diabetes mellitus (T2DM) because of its hypoglycaemic effect. However, its underlying mechanism of action is not fully known.

Objective: To evaluate whether Cγ from M. E. Jones (Fabaceae) modulates c-Jun N-terminal kinase 1 (JNK1) expression and activation in a T2DM rat model.

Materials And Methods: Gamma conglutin isolated from seeds was characterized by SDS-PAGE. Fifteen Wistar rats with streptozotocin-induced T2DM (HG) were randomized into three groups ( = 5): vehicle administration (HG-Ctrl), oral treatment with Cγ (120 mg/kg/day) (HG-Lr) for one week, and treatment with metformin (300 mg/kg/day) (HG-Met); a healthy group (Ctrl,  = 5) was included as control. The levels of glucose and biomarkers of renal and hepatic function were measured pre- and post-treatment. Hepatic expression and phosphorylation of JNK1 were evaluated by qRT-PCR and western blot, respectively.

Results: Oral treatment with either Cγ or metformin reduced serum glucose level to 86.30 and 74.80 mg/dL, respectively ( ˂ 0.05), from the basal levels. expression was 0.65- and 0.54-fold lower ( ˂ 0.05) in the HG-Lr and HG-Met groups, respectively, than in HG-Ctrl. Treatment with Cγ decreased JNK1 phosphorylation. However, Cγ did not change the levels of kidney and liver biomarkers.

Discussion And Conclusions: Treatment with Cγ from inhibited expression, , suggesting JNK1 as a potential therapeutic target in diabetes and revealing one mechanism underlying the hypoglycaemic effect of lupine Cγ. Nevertheless, further studies are required.