RESUMO
ObjectiveTo investigate the immunomodulatory mechanism of Kangxian Yixin prescription （KYP） on autoimmune injury mice and its relationship with the T helper 17 （Th17）/regulatory T cell （Treg） balance. MethodSixty healthy 8-week-old male BALBc mice were randomly divided into a normal group and an experimental group at a ratio of 1∶5. On the 0th， 7th， and 28th days， 0.2 mL of porcine cardiac myosin emulsion （containing 0.1 mg of porcine cardiac myosin） was subcutaneously injected into the groin， armpit， and back of the mice in the experimental group to induce an animal model of myocardial immune injury. Mice with myocardial immune injury were randomly divided into a model group （Model）， a KYP group （20.4 g·kg-1·d-1， ig）， and a valsartan group （12 mg·kg-1·d-1， ig）. Mice in the control group and the model group received the same amount of normal saline by gavage. After four weeks of intervention， the heart tissues were collected. Hematoxylin-eosin （HE） staining and Masson staining were used to detect pathological damage in heart tissues. Enzyme-linked immunosorbent assay （ELISA） was used to detect the expression of type B-type natriuretic peptide （BNP）， anti-cardiac antibody， interleukin-17 （IL-17）， and interleukin-10 （IL-10） in the serum of mice， and the expression levels of Th17 cells and Tregs in the spleen were detected by flow cytometry. The protein expression of B-cell lymphoma-2 （Bcl-2） and Bcl-2-associated X （Bax） in heart tissues was detected by Western blot， and the mRNA expression of retinoid-related orphan receptor gamma t （RORγt） and forkhead box P3 （FoxP3） in the spleen was detected by quantitative real-time polymerase chain reaction （Real-time PCR）. ResultCompared with the control group， the model group showed worsened pathological damage in heart tissues， elevated serum levels of BNP， anti-myocardial antibody， and IL-17， decreased serum expression of IL-10 （P<0.05）， increased expression of Th17 cells and reduced expression of Tregs in spleen tissues （P<0.05）， increased protein expression of Bax， diminished Bcl-2 protein expression， elevated Bax/Bcl-2 ratio， up-regulated mRNA expression of RORγt， dwindled mRNA expression of FoxP3， and elevated ratio of RORγt/FoxP3 （P<0.05）. Compared with the model group， the KYP group and the valsartan group displayed relieved pathological damage in heart tissues， decreased serum expression of BNP， anti-myocardial antibody， and IL-17， increased serum expression of IL-10 （P<0.05）， reduced expression of Th17 cells and increased Tregs in spleen tissues （P<0.05）， dwindled protein expression of Bax and elevated protein expression of Bcl-2 in heart tissues （P<0.05）， diminished Bax/Bcl-2 ratio， reduced mRNA expression of RORγt， up-regulated FoxP3， and down-regulated ratio of RORγt/FoxP3 （P<0.05）. ConclusionKYP may improve myocardial immune damage by regulating the Th17/Treg cell balance.