Objective: To investigate the ameliorating effect of Sinensetin on lung tissue damage in rats infected with respiratory syncytial virus (RSV) through AMP-dependent protein kinase (AMPK)/mammalian target of rapamycin (mTOR) signaling pathway. Methods: 30 male Wistar rats were grouped into control group, model group, low-dose Sinensetin group (14 mg/kg), medium-dose Sinensetin group (28 mg/kg), high-dose Sinensetin group (56 mg/kg), high-dose Sinensetin combined AICAR group (56 mg/kg combined 500 mg/kg of AMPK activator AICAR), the lung index of rats was calculated. The viral load of RSV in lung tissue was determined by quantitative real-time polymerase chain reaction (qRT-PCR). The levels of inflammatory factors in alveolar lavage fluid of rats were determined by enzyme-linked immunosorbent assay (ELISA). Lung histopathology was determined by HE staining, and Western blot was used to measure the expression of AMPK/mTOR pathway proteins. Results: Compared with the control group, the lung tissue of the model group had inflammatory infiltration, and was loosely arranged, the lung index, RSV viral load in lung tissue, levels of interleukin (IL)-1β, IL-6, tumor necrosis factor-α (TNF-α) in bronchoalveolar lavage fluid, inflammation score, expression of p-AMPK/AMPK and mTORC1 protein increased (P<0.05). Compared with the model group, the rats of the low-dose Sinensetin group, the medium-dose Sinensetin group, and the high-dose Sinensetin group had reduced lung tissue damage, the lung index of rats, RSV viral load in lung tissue, levels of IL-1β, IL-6, TNF-α in bronchoalveolar lavage fluid, inflammation score, expression of p-AMPK/AMPK, and mTORC1 decreased (P<0.05). Compared with the high-dose Sinensetin group, the lung tissue damage of the rats of the high-dose Sinensetin combined AICAR group was aggravated, the lung index, RSV viral load in lung tissue, levels of IL-1β, IL-6, TNF-α in bronchoalveolar lavage fluid, inflammation score, expression of p-AMPK/AMPK and MTORC1 increased (P<0.05).Conclusion: Sinensetin may play anti-inflammatory, anti-viral and anti-lung injury effects on RSV-induced rats by inhibiting the activation of AMPK/mTOR signaling pathway. |