Berberine Inhibits Aortic Calcification In Diabetic Rats Through MAPK Signaling Pathway

Objective:To investigate the effect and possible mechanism of berberine on aortic calcification in diabetic rats.Methods:90 male SD rats were randomly divided into 9 groups:Control group,Simple Calcification group,Diabetes group,Diabetes+Calcification group,Diabetes+Calcification+Low concentration of Berberine group?100mg/kg.d?,Diabetes+Calcification+Medium concentration of Berberine group?200mg/kg.d?,Diabetes+Calcification+High concentration of Berberine group?400mg/kg.d?,Diabetes+Calcification+ERK1/2 Inhibitor group,Diabetes+Calcification+p38Inhibitor group.The rats in the control group and the simple calcification group were fed with common fodder.Each diabetes group was fed high-fat-sugar diets.After 4 weeks,the model of type 2 diabetic rat model was established?Streptozotocin?.Continuous determination of random blood glucose in rats after STZ injection,3 or more times consecutive blood glucose values greater than 16.7mmol/L were considered to be successful in rat model diabetes mellitus,add small dose of STZ injection to those whose blood glucose is not up to standard.Each vascular calcification group was given vitamin D ₃?300000 U/kg?intramuscularly at 9:00 am,nicotine?25 mg/kg,dissolved in 5ml peanut oil?gavage,repeated nicotine gavage 1 time at 18:00 pm,the rat vascular calcification model was established.Each berberine group was treated with different concentrations of berberine on the basis of treatment of diabetes vascular calcification.ERK1/2 and p38 inhibitors were treated with correspondinginhibitors?PD980591mg/kg.d,SB2035802mg/kg.d intraperitoneal injection?based on diabetes vascular calcification.The body weight and blood glucose of rat were measured and recorded weekly for 4weeks.After 4 weeks,detection of calcium content in rat aortic tissue using tissue calcium assay kit,detection of aortic medial calcium deposits by Von Kossa staining,detection of aortic medial membrane structure by elastic fiber staining,detection of BMP2 protein expression in rat aortic tissue by immunohistochemistry,theproteinexpressionofOPG,BMP2,Runx2,p-ERK1/2,ERK1/2,p-p38 and p38 in rat aorta was detected by western blotting.Results:1.After feeding with high-fat-sugar diet,the weight gain rate of rats was significantly faster than that of normal feed groups.After the diabetic model was established successfully,the rats in each diabetes group gradually thin and their body weight gradually decreased compared with that before the establishment of the model.Compared with diabetic+calcification group,after berberine treatment,the rate of weight loss in rats slows down.2.After berberine treatment,there was no significant difference in blood glucose changes in rats compared with other diabetes groups?P>0.05?.3.Compared with control group,elastic fiber and Von Kossa staining of rat aorta tissue showed rupture of vascular tissue elastic fibers,and deposition of black calcium salt stained silver particles in the simple calcification group.Compared with simple calcification group,the elastic fiber and Von Kossa staining of rat aorta tissue of diabetes+calcification group showed that the elastic fibers of vascular tissue fracture increased significantly,and there was almost no intact elastic fiber,and the deposition of black calcium salt silver was significantly increased.Compared with diabetes+calcification group,the vascular tissue disorder alleviated,continuous elastic fiber increase,black calcium salt silver stained particles reduced in the ERK1/2 inhibitor group,p38 inhibitor group and different concentrations of berberine groups,and with the increase of berberine concentration,theeffectismoreobvious.4.Comparedwithcontrol group,calcium content of the aortic tissue increased significantly in the simple calcification group?P<0.01?.Compared with simple calcification group,calcium content of the aortic tissue increased significantly in the diabetes+calcification group?P<0.01?.Compared with diabetes+calcification group,calcium content of aortic tissue was reduced significantly in ERK1/2 inhibitor group,p38inhibitor group and different concentrations of berberine group?P<0.01?,and with the increase of berberine concentration,the effect is more obvious.5.Compared with control group,the protein expression of OPG,BMP2,Runx2 in theaortictissueofthesimplecalcificationgroupincreased significantly?P<0.01?.Compared with simple calcification group,the protein expressionofOPG,BMP2,Runx2intheaortictissueofthe diabetes+calcification group increased significantly?P<0.01?.Compared with diabetes+calcification group,the protein expression of OPG,BMP2,Runx2 in the aortic tissue of ERK1/2 inhibitor group,p38 inhibitor group and different concentrations of berberine group decreased significantly?P<0.01?,and with the increase of berberine concentration,the more obvious the decrease.6.Compared with diabetes+calcification group,the protein expression of p-ERK1/2?p-p38of different concentrations of berberine group decreased significantly?P<0.01?,and with the increase of berberine concentration,the effect is more obvious.Conclusion:Berberine can inhibit aortic calcification in diabetic rats,the mechanism may be related to the inhibition of activation of ERK1/2,p38MAPK signaling pathway,decrease of tissue calcium content and calcium deposition,and reduce the expression of OPG,BMP2,Runx2 osteogenic differentiation related proteins.