Abstract:
Objective To investigate the effect of chrysophanol on lipopolysaccharide (LPS)-induced acute lung injury in neonatal rats model through mTOR/HIF-1α/VEGF signaling pathway.
Methods The acute lung injury model in rats was established by intraperitoneal injection of LPS. The rats were divided into 6 groups randomly: control group, model group, chrysophanol at 2.5 mg/kg, 5 mg/kg, 10 mg/kg groups respectively and 5 mg/kg dexamethasone + model group, with 12 rats in each group. The ratio of wet/dry (W/D) of lung tissue was detected using wet-dry method, the arterial oxygen partial pressure (PaO2) was detected by blood gas analyzer, the forced vital capacity (FVC), 0.3 s forced expiratory volume (0.3 s FEV), peak expiratory flow (PEF), middle expiratory flow (MEF) and mean pulmonary artery pressure (mPAP) were measured by pulmonary function analyzer, the pathological injury of lung tissue was detected by HE staining method; the levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were tested using ELISA kits; the changes of pulmonary fibrosis were detected by Masson staining method; the protein expression levels of TGF-β1, α-SMA, collagen Ⅰ, p-mTOR, mTOR, HIF-1α and VEGF were detected by Western blotting.
Results Compared with the model group, in the 5, 10 mg/kg chrysopherol groups and 5 mg/kg dexamethasone groups, the ratio of W/D was decreased (P < 0.01), PaO2 level was increased (P < 0.01), FVC, 0.3 s FEV, 0.3 s FEV/FVC, PEF and MEF rate were increased (P < 0.01), mPAP was decreased (P < 0.01), the pathological injury of lung tissue was improved significantly (P < 0.01), the levels of IL-6, TNF-α and IL-1β in BALF were reduced (P < 0.01), the levels of pulmonary fibrosis were obviously improved (P < 0.01), the protein expression levels of TGF-β1, α-SMA, collagen Ⅰ, p-mTOR/mTOR, HIF-1α and VEGF were decreased (P < 0.01).
Conclusions In LPS induced rats lung injury model, chrysophanol can improve lung pathological injury, inflammatory response and pulmonary fibrosis, which may be associated with the inactivation of mTOR/HIF-1α/VEGF signaling pathway.