The effect of Ulinastatin on autophagy and apoptosis in the acute paraquat poisoning rats lung cellular / 中华急诊医学杂志

ABSTRACT

Objective To investigate the effects of ulinastatin on autophagy and apoptosis of lung cells in rats with acute paraquat poisoning.Methods A total of 150 Wistar rats were randomly (random number) divided into three groups.The rats in control group had stomach lavaged once with 1 mL of normal saline followed by intraperitoneal injection of 1 mL normal saline twice a day.PQ poisoning model was produced by stomach lavaged once with 1 mL of 40 mg/kg PQ solution followed by intraperitoneal injection of 1 mL normal saline once a day.In PQ + ulinastatin (PU) group,UTI in dose of 12 000 U/kg was intraperitoneally injected in rats twice a day.The lung tissue was obtained on the 7th day after modeling,and the histopathological changes were observed under microscope after hematoxylin and eosin (HE) staining.The positive expressions of autophagy-related LC3 protein LC3 and Bcl-2 pretein in lung tissue were observed after immunohistochemistry staining,and the levels of LC3、Bax 、Bcl-2 proteins were determined by Western blot.Results HE staining Results showedit was observed from the PQ poisoning group that the abnormal cellular structure,enlargement in the pulmonary alveoli,leaking a lot of inflammatory cells,increased thickness of the alveoli wall and bleeding in the local area of lung tissue.Compared with the PQ poisoning group,the above changes in ulinastatin groups were relieved.Western blot Results showedcompared with the control group,the protein expressions of LC3-A/B were significantly increased in PQ poisoning group [LC3-A/B expression (A scale)0.22 ± 0.05 vs.0.14 ± 0.03,F =22.48,P ＜ 0.01].compared with PQ group,the expression of LC3 A/B obviously increased in the group of PU [LC3-A/B expression (A scale)0.36 ± 0.08 vs.0.22 ± 0.05,F =22.78,P ＜ 0.01].compared with Con group,the expression of Bcl-2/Bax obviously decreased in the group of PQ [Bcl-2/Bax expression (A scale),0.11 ±0.04 vs.0.83 ± 0.09,F =154.43,P ＜ 0.01].Compared with PQ poisoning group,the protein expressions of Bcl-2/Bax were obviously increased in PU groups [Bcl-2/Bax expression (A scale)(0.63 ± 018) vs.(0.11 ±0.04),F =154.43,P ＜0.01].Immunohistochemistry result:compared with Con group,the expression of LC3 and Bcl-2 obviously decreased in the group of PQ [LC3expression (A scale)(78.34±10.71) vs.(117.58±15.26),F=31.63,P＜0.01) (Bcl-2 expression (A scale)(62.54±9.74)vs.(130.52 ± 9.86,F =118.44,P ＜ 0.01).Compared with PQ poisoning group,the protein expressions of LC3 and Bcl-2 were obviously increased in PU groups [LC3expression (A scale)(162.58 ± 25.76) vs.(78.34 ± 10.71),F=31.63,P＜0.01]; [Bcl-2 expression (A scale)(145.56±10.26) vs.(62.54±9.74),F=118.44,P ＜ 0.01].Conclusions Theendoplasmic reticulum stress-autophagy is activated in the lung cells of rats with acute PQ poisoning.UTI can adjust endoplasmic reticul um stress,increased the expression of Bcl-2 and enhance the proportion of Bcl-2/Bax to protect the lungs of rats from acute PQ poisoning.