Effect of Gegen Qinliantang on TLR4/IKKβ/NF-κB Pathway in KKAy Mice with Diabetes / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo observe the effect of classical prescription Gegen Qinliantang（GGQLT） on inflammatory factors and key targets in the inflammatory pathways mediated by lipopolysaccharide in KKAy mice and explore its mechanism in improving spontaneous type 2 diabetes mellitus （T2DM）. MethodSixty-five SPF KKAy mice with spontaneous T2DM and 13 C57BL/6J mice （control） were selected in the barrier system and fed on a high-fat diet. The model was properly induced in 44 mice in the context of random blood glucose exceeding or equal to 13.9 mmol·L-1. Then the mice were assigned into a normal group （20 mL∙kg-1 normal saline）， a model group （20 mL∙kg-1 normal saline）， an acarbose group （3.9 mg∙kg-1）， and high- and low-dose GGQLT groups （1.82 and 0.45 g∙kg-1）， with 11 mice in each group. The mice in each group were treated correspondingly by gavage for eight weeks， once per day. Blood glucose and body weight were systematically evaluated. Twelve hours after the last administration， blood samples were collected from the eyes， and the serum and muscle and liver tissues were extracted. The levels of tumor necrosis factor-α （TNF-α）， interleukin-6 （IL-6）， and glucose transporter type 4 （GluT4） were detected by semi-quantitative enzyme-linked immunosorbent assay （ELISA）. The protein expression of IκB kinase β （IKKβ） and nuclear factor-κB （NF-κB） in muscle tissues and Toll-like receptor 4 （TLR4） in liver tissues was detected by Western blot. ResultCompared with the normal group， the model group showed increased body weight and blood glucose （P<0.01）. Compared with the model group， the acarbose group and the GGQLT groups showed reduced body weight and blood glucose （P<0.05， P<0.01）. As revealed by ELISA results， compared with the normal group， the model group showed increased levels of TNF-α and IL-6 （P<0.01） and deceased GluT4 level （P<0.05）. Compared with the model group， the groups with drug treatment showed reduced levels of TNF-α and IL-6 （P<0.05， P<0.01）， and the acarbose group and the high-dose GGQLT group showed increased GluT4 level （P<0.05， P<0.01）. As displayed by Western blot results， compared with the normal group， the model group showed increased protein expression of IKKβ， NF-κB， and TLR4 （P<0.01）. Compared with the model group， the acarbose group and the GGQLT groups showed reduced protein expression of IKKβ， NF-κB， and TLR4 （P<0.05， P<0.01）. ConclusionGGQLT can inhibit the inflammatory cascade effect and improve T2DM by down-regulating the levels of key inflammatory factors in the TLR4 pathway， inhibiting their activation， and increasing the translocation and activity of GluT4 on the basis of the regulation of intestinal flora.