罗格利酮对伴高脂血症大鼠重症急性胰腺炎肺损伤的作用研究

目的 探讨罗格列酮(ROSI)对伴高脂血症大鼠重症急性胰腺炎(SAP)肺损伤的保护作用及其可能机制.方法 雄性SD大鼠120只,脂肪乳剂灌胃两周.随机(随机数字法)分为6组:高脂血症组(HL)、伴高脂血症SAP组(HP)、罗格列酮干预组(HRP)、罗格列酮拮抗组(HRGP)、罗格列酮对照组(HR)、拮抗剂对照组(HG),每组各20只.HP组、HRP组及HRGP组逆行胰胆管注射5％牛磺胆酸钠(1 mL/kg)建立SAP模型.HL组、HR组和HG组操作同HP组、HRP组及HRGP组,但胰胆管内仅注入等容量生理盐水;HRP组和HR组于造模前经股静脉注射ROSI (10 mg/kg);HRGP组于注射ROSI前30 min经股静脉注射GW9662(0.3 mg/kg),其余操作同HRP组,HG组仅于造模前30 min经股静脉注射GW9662 (0.3 mg/kg).于12h观察大鼠胰腺、肺脏病理学变化;计算肺湿干比(W/D);测定血清淀粉酶(AMY)、甘油三酯(TG)、总胆固醇(TC)的含量;免疫组织化学法检测各组肺组织NF-κB p65蛋白的表达;Western-Blot法检测各组肺组织肿瘤坏死因子(TNF-α)及细胞间黏附分子(ICAM-1)的蛋白表达水平.结果 HL组和HP组的TG、TC的血清水平均明显高于HR组和HRP组(1.24±0.28,1.14±0.08vs.0.41±0.17,0.58 ±0.12;14.86±1.47,12.42 ±0.96 vs.6.52±2.04,7.36±0.95;均P＜0.05);HP组、HRGP组大鼠血清AMY、肺湿干比(W/D)、胰腺、肺组织病理学评分、肺组织NF-κB p65蛋白表达及TNF-α、ICAM-1蛋白表达水平均较HL组、HR组及HG组的各项指标有显著升高(6 501.9±3 770.0,5 922.2±925.9 vs.1 139.3 ±35.6,1 070.8 ±67.0,1 012.4 ±94.7;3.14 ±0.16,3.06±0.12 vs.1.81 ±0.13,1.76±0.23,1.83 ±0.18;均P＜0.05);HRP组的大鼠肺脏病理学评分、肺湿干比(W/D)、肺组织NF-κB p65蛋白表达及TNF-α、ICAM-1蛋白表达水平均较HP组和HRGP组有所降低(均P ＜0.05),HRGP组各项指标均与HP组差异无统计学意义(均P＞0.05).HL、HR及HG三组的各项指标进行相互比较,差异无统计学意义(均P＞0.05).结论 PPAR-γ激动剂罗格列酮可以降低伴高脂血症SAP大鼠肺水肿程度,并可以通过降低血脂水平和抑制肺组织NF-κB的表达,减少其下游炎性因子TNF-α和ICAM-1的表达,对伴高脂血症SAP大鼠肺损伤产生保护作用.

Effects of rosiglitazone on hyperlipidemic rats with severe acute pancreatitis secondary to lung injury

Objective To explore the effects of rosiglitazone (ROSI),a peroxisome proliferator-activated receptors-gamma (PPAR-γ) ligand,on hyperlipidemia in rats with severe acute pancreatitis (SAP) associated with lung injury.Methods A total of 120 male SD rats received intragastric administration of high fat diet for two weeks to induce experimental hyperlipemia.The hyperlipidemic rats were randomly (random number) divided into six groups:hyperlipidemia (HL) group (n =20),hyperlipidemia with SAP (HP) group (n =20),hyperlipidemia with rosiglitazone intervention (HRP) group (n =20),hyperlipidemia with rosiglitazone and antagonist to rosiglitazone (HRGP) group (n =20),rosiglitazone control (HR) group (n =20) and antagonist control (HG) group (n =20).The SAP was induced by a retrograde infusion of 5％ sodium tauroholate into bile-pancreatic duct,and the SAP was established in HP group,HRP group and HRGP group.In HL group,HR group and HG group,equivalent volume of normal saline was used instead of sodium taurocholate.In HRP group and HR group,ROSI (6 mg/kg) was administered via the femoral vein 1 hour prior to the administration of sodium taurocholate.In HRGP group,GW9662 (0.3 mg/kg),an antagonist to PPRA-gamma,was given via the femoral vein 30 min prior to the administration of ROSI.In HG group,only GW9662 (0.3 mg/kg) was given via the left femoral vein 30 min prior to pretend SAP modeling.Rats from each group were sacrificed by exsanguination 12 h after SAP modeling.Blood samples were taken from all subjects to measure serum amylase (AMY),total cholesterol (TC),triglycerides (TG),Successive sections of the paraffin embedded tissue from pancreas and lung were taken for pathological examination with hematoxylin-eosin (HE) staining.Histopathological changes of pancreatic and pulmonary tissues observed under light microscope were evaluated.In pulmonary tissue,nuclear factor-kappa B (NF-κB) p65 expression was assayed by immunohistochemistry.Intercellular adhesion molecule (ICAM-1) protein and tumor necrosis factor-α (TNF-γ) protein levels were studied using Western blot analysis.Results The serum levels of TC and TG in HL group and HP group were significantly higher than those in HR group and HRP group (1.24 ± 0.28,1.14 0.08 vs.0.41 ±0.17,0.58±0.12;14.86±1.47,12.42±0.96 vs.6.52±2.04,7.36±0.95,allP＜ 0.05);The levels of serum AMY,W/D ratio,pancreas pathologic score,lung pathologic score,expression of NF-κB p65,ICAM-1 and TNF-α in pancreas in the HP group and HRGP group were significantly higher than those in HL group,HR group,and HG group (6 501.9 ±3 770.0,5 922.2 ±925.9 vs.1 139.3 ± 35.6,1 070.8 ±67.0,1 012.4 ±94.7;3.14±0.16,3.06±0.12vs.1.81 ±0.13,1.76±0.23,1.83 ± 0.18;all P ＜0.05);Compared with the HP group and HRGP group,the levels of serum AMY,TC and TG were significantly decreased in HR group and HRP group,ameliorating pancreas and lung pathological damage,and down-regulating the expression of NF-κB p65,ICAM-1 and TNF-α in pulmonary tissue (all P ＜ 0.05).While there were no statistically significant differences in above biomarkers between HP group and HRGP group (all P ＞ 0.05).Conclusions Our study demonstrates that ROSI exerts anti-hyperlipidemic effect and anti-inflammatory effect on hyperlipidemia in rats with sodium taurocholate-induced severe acute pancreatitis associated with lung injury by inhibiting NF-κB and down-regulating the expression of TNF-α and ICAM-1.