疏肝补肾方对被动型Heymann肾炎大鼠IL-6及TGF-β1/Smad信号通路的影响OA

Objective:To observe therapeutic effects of liver-soothing kidney-invigorating prescription on rats suffering passive Heymann nephritis(PHN),and to discuss the mechanism of the prescription in preventing and treating MN.Methods:All 32 male SD rats were randomly divided into a blank control group(n=8)and a model induction group(n=24).The model induction group received an injection of sheep anti-rat Fx1A serum via the tail vein to establish the PHN rat models.After successfully modeling,PHN rats were randomized into the model group,liver-soothing kidney-invigorating prescription group and Western medicine group with eight in each.The rats began to receive intragastric administration for intervention after grouping:liver-soothing kidney-invigorating prescription group was drenched with the solution of liver-soothing kidney-invigorating prescription at a dose of 11.7 g·kg-1·d-1;Western medicine group accepted the gavage of the suspension of prednisone acetate(1 mg·kg⁻¹·d⁻¹)combined with cyclophosphamide(3 mg·kg⁻¹·d⁻¹);the blank control group and the model group were administered with the same amount of physiological saline.All the groups accepted intragastric administration once each day,for four weeks in a row.Urine samples of the rats were collected for 24 hours at one week after modeling(before the start of intervention)and at 1,2,and 4 weeks of intervention,ELISA was adopted to detect the levels of 24 h UP.After four weeks of the intervention,blood was collected from the inferior vena cava,ELISA was applied to measure the levels of IL-6 in the serum;renal tissue samples were collected from the rats for pathological morphological observation under light microscope and electron microscope,respectively.The expressions of TGF-β1,Smad2 and Smad7 mRNA in renal tissues were tested using qRT-PCR method.Results:After four weeks of the intervention,the levels of 24h UP in liver-soothing kidney-invigorating prescription group and Western medicine group were lower than these in the model group,and the decrease in Western medicine group was more evident,and the difference demonstrated statistical meaning(P<0.05);The difference was not statistically significant in the levels of 24h UP between liver-soothing kidney-invigorating prescription group and Western medicine group(P>0.05).The difference was not statistically significant in the levels of IL-6 between all the groups(P>0.05).Light microscopy of PAS-stained kidney tissue showed that,compared with the model group,pathological changes such as glomerular enlargement,basement membrane thickening,and capillary loop rigidity were alleviated in both the Western medicine group and the liver-soothing kidney-invigorating prescription group.Electron microscopy showed that in the Western medicine group and liver-soothing kidney-invigorating prescription group,the degree of basement membrane thickening was reduced,the extent of foot process fusion was decreased,and only sparse deposition of a small amount of electron-dense deposits was observed.Results of molecular biology assays revealed that:compared with the blank control group,the expressions of TGF-β1 and Smad2 mRNA showed an upward trend,while the expressions of Smad7 mRNA presented an downward trend,but the difference had no statistical meaning(P>0.05);the levels of Smad7 mRNA in renal tissue was significantly decreased in the Western medicine group(P<0.05);compared with the model group,the Western medicine group and liver-soothing kidney-invigorating prescription group demonstrated the lowered levels of TGF-β1 and Smad2 mRNA,and the decrease in the expressions of Smad2 mRNA was more noticeable(P<0.05).Conclusion:Liver-soothing kidney-invigorating prescription could lower the levels of urinary protein and relieve renal histopatho-logical lesions in rats with PHN,and downregulate the expressions of TGF-β1 and Smad2 mRNA in the renal tissue,and affecting TGF-β1/Smad signaling pathway,thereby inhibiting renal tissue fibrosis and delaying the progression of MN.