Puerarin prevents isoprenaline-induced myocardial fibrosis in mice by reduction of myocardial TGF-β1 expression.

It has been reported that soy isoflavones could significantly increase peroxisome proliferator-activated receptor α/γ gene expressions, while the activation of peroxisome proliferator-activated receptor α/γ may attenuate myocardial fibrosis. Puerarin is the main isoflavone isolated from the root of the wild leguminous creeper Pueraria lobata (Willd) Ohwi, so we thought that puerarin could inhibit myocardial fibrotic formation. A mouse myocardial fibrotic model was induced by hypodermic injection of isoprenaline when these mice were simultaneously treated with puerarin 600 and 1200 mg/kg by gavage for 40 days, respectively. The results showed that puerarin could significantly improve myocardial fibrosis and decrease the collagen accumulation, collagen volume fraction, hydroxyproline content in myocardial tissue and cardiac weight index. The results from reverse transcription polymerase chain reaction indicated that the messenger RNA (mRNA) expression of transforming growth factor-β1 in myocardial tissue was decreased, while the mRNA expressions of peroxisome proliferator-activated receptor α/γ were increased, in the puerarin groups as compared with the model group. Importantly, puerarin could significantly decrease the protein expressions of transforming growth factor-β1 and nuclear factor-κB in myocardial tissue. These results suggested that puerarin could prevent isoprenaline-induced myocardial fibrosis in mice, and its mechanisms might be related to reduction of transforming growth factor-β1 expression via activation of peroxisome proliferator-activated receptor α/γ and subsequent inhibition of nuclear factor-κB in myocardial tissue.