Conclusions
Although thalidomide and the DPP4 inhibitor had an immunomodulatory effect and are used against inflammatory diseases, they did not ameliorate myocardial inflammation and fibrosis in this rat model of EAM.
Methods
Rats with or without myocarditis were administered thalidomide at 100 mg/kg/day and DPP4 inhibitor at 10 mg/kg/day orally. Measurement of echocardiography, serum inflammatory cytokines, myocardial histopathological examination, and immunohistochemical staining for leukocytes, macrophages, CD4+ T cells, and cytoskeleton were performed after 3 weeks, and the fibrosis area was measured after 3 and 6 weeks.
Results
Thalidomide and DPP4 inhibitor did not reduce the severity of myocarditis compared with the EAM without treatment rats by comparing the echocardiographic data, myocardial CD4+, macrophages, neutrophil infiltrations, and the heart weight/body weight ratio in 3 weeks. The levels of inflammatory cytokines were not lower in the thalidomide and DPP4 inhibitor-treated group than in the untreated group in 3 weeks. In 6 weeks, thalidomide and DPP4 inhibitors did not reduce the fibrosis area compared to untreated groups. Conclusions: Although thalidomide and the DPP4 inhibitor had an immunomodulatory effect and are used against inflammatory diseases, they did not ameliorate myocardial inflammation and fibrosis in this rat model of EAM.
