| Objective:Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) are caused by a series damage factors such as trauma, microbial infection, aspiration and drugs, with high morbidity and high mortality rate. Current treatment is limited, and the prognosis is very poor. Uncontrolled and amplification of the inflammatory response participate in the development of ALI/ARDS, seriously affect the prognosis of patients. This study established a lipopolysaccharide (LPS)-induced mice ALI secondary to sepsis, discussed protective effect of Rho kinase inhibitor fasudil on ALI in mice induced by LPS and its possible mechanism.Methods:Male C57BL/6mice were randomly assigned to control group, LPS group, fasudil+LPS group, dexamethasone (Dex)+LPS group. Mortality rates of different time points of each group were assessed after the model established. The other mice were sacrificed at6h after LPS injection. Serum, bronchoalveolar lavage fluid (BALF) and lung tissues were collected. The wet-to-dry (W/D) weight and the myeloperoxidase (MPO) content were measured; inflammatory cells infiltration in lung tissues and tissue injury were observed with hematoxylin and eosin (HE) staining; cell counting and protein content were analyzed in BALF; the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-10(IL-10) in serum were measured using Enzyme-linked immunosorbent assay (ELISA) method; and the expression of bcl-2, bax, caspase-3in lung tissue were analyzed through western blot (WB) method.Results:1. LPS30mg/kg intraperitoneal injection can significantly induced sepsis associated ALI and increased the risk of death in ALI mice, fasudil and Dex significantly improved the survival rate and prolonged survival time of mice.2. W/D ratio in LPS group (5.10±0.61) was significantly increased than the control group (4.01±0.41)(P<0.05), however, the W/D ratio of LPS+fasudil group (4.32+0.32) and LPS+Dex group (4.27±0.33) was significantly decreased than that of the LPS group (P<0.05).3. HE staining to observe the pathology change of lung tissue. Alveolar structure of control group was integrity and unchanged. Whereas, alveolar structure of LPS group was disorder, including lung tissue hemorrhage, edema, inflammatory cells infiltration, thickness of alveolar walls, etc. LPS+fasudil group and LPS+Dex group changed lighter in lung tissue pathology compared with the LPS group. The score of lung tissue pathology in LPS group was10.83±0.87, which was significantly increased compared with that of control group (1.00±0.26)(P<0.05), LPS+fasudil group and LPS+Dex group scores were7.33±0.88and0.88±1.11, which were significantly decreased than that of the LPS group (P＜0.05).4. The content of protein in BALF [(1032±207.2) μg/ml] in LPS group, was significantly increased compared with the control group (295.5±78.65) μg/ml)(P<0.05), LPS+fasudil group, the LPS+Dex group content of protein in BALF [respectively (563.3±96.60)μg/ml and (495.2±146.9)μg/ml], were significantly decreased compared with the LPS group (P＜0.05).5. MPO content of lung tissue in LPS group (3.40±0.62) was significantly higher than that of control group (1.07±0.44)(P＜0.05), MPO content in LPS+fasudil group (2.42±0.70) and LPS+Dex group(2.19±0.40) were significantly lower than that of the LPS group (P＜0.05).6. In LPS group, the serum level of TNF-α、IL-1β [respectively (614.8±30.85) pg/ml,(88.45-7.47) pg/ml] were significantly higher than the control group [respectively (19.19±2.80) pg/ml and (23.02±3.39) pg/ml](P <0.05); LPS+fasudil group and LPS+Dex TNF-a value were respectively (377.1±33.68pg/ml and (39.08±5.723) pg/ml, IL-1β value were respectively (56.76±5.62) pg/ml and (47.14±3.70)pg/ml, which were significantly decreased compared with LPS group (P<0.05). In LPS group, the serum level of IL-10was (117.7±336.26) pg/ml, which was significantly increased compared with that of control group [(16.73±3.66) pg/ml](P<0.05), LPS+fasudil group, the LPS+Dex group IL-10level were respectively (248.3±56.10) pg/ml and (311.6±51.5) pg/ml, which were significantly increased compared with that of LPS group was (P<0.05).7. Expression of bax, cleaved caspase-3in LPS group were obviously higher than that of control group (P<0.05), the expression of LPS+fasudil group and LPS+Dex group were decreased than that of LPS group (P<0.05). Expression of bcl-2in LPS+fasudil group was increased compared with that of LPS group(P<0.05). bcl-2/bax ratio in LPS group was significantly decreased than that of control group (P<0.05), the ratio in LPS+fasudil group and LPS+Dex were increased than that of LPS group (P＜0.05).Conclusion:Pre-administration of fasudil significantly reduced LPS induced ALI in mice, it improved the general condition and survival rate of mice, The protective mechanism is probably through remissioning pulmonary edema, infiltrating of pulmonary inflammatory cells, balancing proinflammatory cytokines and anti-inflammatory cytokine, alleviating systematic inflammation reaction and cell apoptosis in lung tissue. |
PDF Full Text Request