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

Abstract

Context: Gamma conglutin (Cc) 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 Cc from Lupinus rotundiflorus M. E. Jones (Fabaceae) modulates c-Jun Nterminal kinase 1 (JNK1) expression and activation in a T2DM rat model. Materials and methods: Gamma conglutin isolated from L. rotundiflorus seeds was characterized by SDS-PAGE. Fifteen Wistar rats with streptozotocin-induced T2DM (HG) were randomized into three groups (n ¼ 5): vehicle administration (HG-Ctrl), oral treatment with Cc (120 mg/kg/day) (HG-Lr) for one week, and treatment with metformin (300 mg/kg/day) (HG-Met); a healthy group (Ctrl, n ¼ 5) was included as control. The levels of glucose and biomarkers of renal and hepatic function were measured pre-and post-treatment. Hepatic Jnk1 expression and phosphorylation of JNK1 were evaluated by qRT-PCR and western blot, respectively. Results: Oral treatment with either Cc or metformin reduced serum glucose level to 86.30 and 74.80 mg/ dL, respectively (p ˂ 0.05), from the basal levels. Jnk1 expression was 0.65-and 0.54-fold lower (p ˂ 0.05) in the HG-Lr and HG-Met groups, respectively, than in HG-Ctrl. Treatment with Cc decreased JNK1 phosphorylation. However, Cc did not change the levels of kidney and liver biomarkers. Discussion and conclusions: Treatment with Cc from L. rotundiflorus inhibited Jnk1 expression, in vivo, suggesting JNK1 as a potential therapeutic target in diabetes and revealing one mechanism underlying the hypoglycaemic effect of lupine Cc. Nevertheless, further studies are required.

Effect of Lupinus albus Conglutin Gamma Protein on Experimentally Induced Diabetes in Rats

“…When there are no reducing conditions, only one band of roughly 50 kDa is visible for Cγ (lane 2). As anticipated, under reducing circumstances, two prominent bands of approximately 17 and 29 kDa formed; these bands were the two Cγ sub-units (Figure 1 lane 3) [27].…”

Effect of Lupinus albus conglutin gamma protein on experimentally induced diabetes in rats

“…As anticipated, under reducing circumstances, two prominent bands of approximately 17 and 29 kDa formed; these bands were the two Cγ sub-units (Fig. 1 lane 3) [27] Effect of Conglutin Gamma on serum lipid pro le…”

Lupinus albus γ-Conglutin: New Findings about Its Action at the Intestinal Barrier and a Critical Analysis of the State of the Art on Its Postprandial Glycaemic Regulating Activity

“…Over the last two decades, lupins (Lupinus albus, L. angustifolius, and L. mutabilis) have attracted particular attention for their hypoglycaemic, hypocholesterolemic, and anti-inflammatory properties, especially regarding protein fractions [7][8][9][10]. Among them, γ-conglutin (γ-C) has been extensively studied for its postprandial glycaemic regulating activity in vitro [11,12], in vivo [13][14][15][16][17][18][19][20], ex vivo [21], and in humans [11,[22][23][24]. The consumption of foods containing bioactive proteins and/or peptides that can help in managing different chronic diseases (e.g., diabetes) is nowadays gaining attention.…”