Objective To investigate the role of IFN-γ in suppressing bleomycin-induced pulmonary fibrosis in rats.Methods Seventy-five SD rats were randomly divided into five groups (15 rats in each group)，ie.a normal group，a bleomycin-induced pulmonary fibrosis model group，a dexamethasone-treated group，a high-dose IFN-γ-treated group (150 000 U/kg) and a low-dose IFN-γ-treated group (50 000 U/kg).Five rats in each group were randomly killed in 7th day，14th day and 28th day after relative treatment respectively，and lung tissue samples were harvested for histopathology study.HE and Masson staining were used to determine the extent of alveolus inflammation and pulmonary fibrosis respectively.Histoimmunochemical method were adapted to determine protein levels of TGF-β1，CTGF，type Ⅰcollagen and type Ⅲ collagen in pulmonary tissues.Results Histopathological study showed that treatment with either dexamethasone or IFN-γ (both high dose and low dose) remarkably meliorated the extent of alveolus inflammation and suppressed pulmonary fibrosis (compared with model group，all Plt;0.05).Histoimmunochemical study suggested that both dexamethasone and IFN-γ could inhibit the expression of TGF-β1，CTGF，type Ⅰand type Ⅲ collagen (compared with model group，all Plt;0.05)，and the suppression of TGF-β1，type Ⅰand type Ⅲ collagen expression was more obvious in high-dose IFN-γ-treated group than those in low-dose group (Plt;0.05).Conclusions INF-γ possesses apparent anti-fibrosis effect that is similar to dexamethasone but with less side effect.Such effect may resulted from reduced production of type Ⅰand type Ⅲ collagen through expression inhibition of cytokines such as TGF-β1 and CTGF.
Objective To investigate the effects of extracellular signal regulated kinase ( ERK)signaling pathway on cell cycle of airway smooth muscle cells( ASMCs) in asthmatic rats. Methods Thirty Wistar rats were randomly assigned to a control group and an asthma group( 15 rats in each group) . Asthma model was established by ovalbumim sensitization and challenge. ASMC were isolated and cultured in vitro. The ASMCs from the asthmatic rats were treated with ERK activator epidermal growth factor ( EGF)and inhibitor PD98059, respectively. The expressions of cyclin D1 and CDK2 in ASMCs were detected by immunocytochemical staining. The expressions of ERK1 /2 and p-ERK1 /2 protein were observed by western blotting for measurement of ERK activation rate. Results Compared with the control group[ 54. 17 ±6. 11,61. 04 ±4. 09, ( 49. 91 ±3. 26) % , respectively] , the expressions of cyclin D1 protein and CDK2 protein,and the rate of ERK activation of ASMCs from the asthmatic rats significantly increased[ 76. 15 ±4. 88,92. 30 ±7. 95, ( 82. 37 ±5. 78) % , respectively] ( P lt; 0. 05) . Furthermore, compared with those before treatment, the expression of cyclin D1 and CDK2, and the rate of ERK activation of ASMCs significantly decreased after treatment with PD98059 [ 58. 78 ±4. 60, 69. 15 ±5. 83, ( 54. 01 ±4. 12) % , respectively]( P lt; 0. 05) , and significantly increased after treatment with EGF[ 119. 28 ±8. 14, 134. 77 ±9. 26, ( 91. 57 ±5. 32) %, respectively] ( P lt;0. 05) . Conclusion ERK1/ 2 participates in proliferation regulation of ASMCs in asthma by enhancing the expressions of cyclin D1 and CDK2, which promotes quiescent cells into S phase.
Objective To review the changes of gut microbiota after bariatric surgery and the related mechanisms of improving metabolism. Method Domestic and international literatures in recent ten years on the changes of gut microbiota in bariatric surgery and the mechanisms of improving metabolism were collated and summarized. Result The common bariatric procedures performed to date were vertical sleeve gastrectomy (VSG) and laparoscopic Roux-en-Y gastric bypass (RYGB). The changes of gut microbiota vary in different surgical procedures, which were related to the changes of diet habits, gastrointestinal anatomy, gastrointestinal hormone levels and metabolic complications. The gut microbiota might improve the body metabolism by regulating the levels of short chain fatty acids, branched chain amino acids and bacterial endotoxin in the intestinal lumen. Conclusions Significant changes are found in gut microbiota after bariatric surgery, which may be involved in the improvement of body metabolism by regulating the level of bacterial endotoxin and microbial metabolite. However, more in-depth mechanisms need to be further clarified.