Effect of Baihu Jia Renshen Tang on PI3K/Akt Signaling Pathway in Liver of MKR Diabetic Mice / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo explore the effects of Baihu Jia Renshen Tang （BHRS） on the related molecules on the phosphatidylinositol-3-kinase/protein kinase B（PI3K/Akt）signaling pathway in the liver of MKR diabetic model mice. MethodThirty 6-week-old MKR mice were selected and fed on a high-fat diet for four weeks，followed by intraperitoneal injection of streptozotocin（STZ）for the diabetes model establishment. The model was properly induced in the case of the fasting blood glucose （FBG） of ≥11.1 mmol·L-1. After modeling，the mice were randomly divided into a model group，a BHRS group （12.09 g·kg-1·d-1），and a metformin group （0.065 g·kg-1·d-1），with 10 mice in each group. Ten FVB mice were assigned to the control group. The mice in the groups with drug intervention were continuously administered correspondingly for 28 days. After administration，the mice were sacrificed，followed by the oral glucose tolerance test （OGTT） and FBG detection. Serum very low-density lipoprotein（VLDL）content was determined by semi-quantitative enzyme-linked immunosorbent assay （ELISA）. Four indexes related to blood lipid were determined by the biochemistry analyzer. Liver tissues were subjected to pathological examination by hematoxylin-eosin（HE）staining. Western blot was used to detect the protein expression of PI3K，Akt，phosphorylated（p）-PI3K，p-Akt，forkhead box protein O1 （FoxO1），insulin receptor（InsR），and insulin receptor substrate-2（IRS-2） in liver tissues of mice. Real-time polymerase chain reaction（Real-time PCR） was used to detect the mRNA expression of PI3K，Akt，FoxO1，InsR，and IRS-2 in liver tissues of mice. ResultCompared with the control group，the model group showed poor general conditions，abnormal glucose tolerance （P<0.05），increased FBG （P<0.01），abnormal blood lipid metabolism，increased serum total cholesterol （TC），triglyceride（TG），low-density lipoprotein cholesterol（LDL-C），and VLDL （P<0.05），decreased level of high-density lipoprotein cholesterol（HDL-C）（P<0.05），fatty degeneration and obvious pathological changes of liver cells，reduced protein expression of PI3K，Akt，p-PI3K/PI3K，p-Akt/Akt，IRS-2，and InsR in liver tissues（P<0.05），increased protein expression of FoxO1（P<0.05），decreased mRNA expression of PI3K，Akt，IRS-2，and InsR in liver tissues （P<0.05），and increased FoxO1 mRNA expression（P<0.05）. Compared with the model group，the BHRS group showed improved general conditions and glucose and lipid metabolism （P<0.05），improved pathological state of liver cells，increased protein expression of PI3K，Akt，p-PI3K/PI3K，p-Akt/Akt，IRS-2，and InsR in liver tissues（P<0.05），decreased protein expression of FoxO1（P<0.05），increased mRNA expression of PI3K，Akt，IRS-2，and InsR in liver tissues （P<0.05），and reduced FoxO1 mRNA expression（P<0.05）. ConclusionBHRS can effectively reduce blood glucose，regulate blood lipid metabolism，and improve the pathological state of the liver in MKR diabetic mice，and its mechanism of action may be related to the regulation of the activity of molecules on the PI3K/Akt signaling pathway.