内源性硫化氢调节慢性阻塞性肺疾病大鼠氧化/抗氧化平衡

Endogenous hydrogen sulfide regulates oxidant/antioxidant balance in rat with chronic obstructive pulmonary disease

目的:探讨硫化氢(H2S)在吸烟(CS)联合脂多糖(LPS)建立的大鼠慢性阻塞性肺疾病(COPD)模型中的抗氧化作用。方法:32只清洁级健康雄性SD(Sprague-Dawley)大鼠,随机分为4组:对照组(control)、CS+LPS组、CS+LPS+硫氢化钠(NaHS,H2S供体)组、CS+LPS+炔丙基甘氨酸(PPG,胱硫醚-γ-裂解酶抑制剂)组。30 d后测定大鼠肺功能,光镜观察肺组织病理变化并予评分;测定血浆中H2S含量及肺组织中胱硫醚-γ-裂解酶(CSE)蛋白表达;检测肺组织中丙二醛(MDA)含量、超氧化物歧化酶(SOD)及过氧化氢酶(CAT)活性以反映氧化应激。结果:与对照组相比,CS+LPS组大鼠呼气峰流速(PEF)下降24%(P<0.01),气道内压(IP)升高66%(P<0.01),肺组织病理评分升高(P<0.01);NaHS或PPG干预后,与CS+LPS组比较,肺功能无改变;NaHS干预后,病理评分下降(P<0.05)。在第16 d时,CS+LPS组血浆中H2S含量较对照组升高26%(P<0.05);30 d后,CS+LPS+PPG组较CS+LPS组H2S含量降低22%(P<0.01)。CS+LPS组中CSE蛋白表达较对照组升高(P<0.01);与CS+LPS组比较,CS+LPS+NaHS组和CS+LPS+PPG组无显著差异。与对照组相比,CS+LPS组肺组织中MDA含量升高24%(P<0.05),总SOD活性升高47%(P<0.01),CAT活性升高52%(P<0.01);与CS+LPS组相比,NaHS干预后,MDA含量降低21%(P<0.05),总SOD活性及CAT活性无显著差异;而PPG干预后,总SOD活性下降33%(P<0.05)。结论:H2S在COPD大鼠中起到抗氧化作用,CSE/H2S途径可能参与COPD疾病的发展。

AIM：To investigate the role of hydrogen sulfide（H2S） in the protection against oxidative stress in rats with chronic obstructive pulmonary disease（COPD）.METHODS： The rat model of COPD was established by cigarette smoking（CS） combined with lipopolysaccharide（LPS） instillation.Thirty-two healthy male Sprague-Dawley rats were randomly divided into 4 groups： control group,CS＋LPS group,CS＋LPS＋NaHS（H2S donor） group and CS＋LPS＋PPG（DL-propargylglycine,an inhibitor of cystathionine-γ-lyase） group.After 30 days,the lung functions of the rats were measured,the histological changes of lungs were observed under light microscope and the pathological scores were calculated.The H2S level in plasma and the protein expression of cystathionine-γ-lyase（CSE） in the lung tissues were measured.The content of malondialdehyde（MDA）,the activity of superoxide dismutase（SOD） and catalase（CAT） were detected to reflect oxidative stress.RESULTS： Compared with control group,the peak expiratory flow（PEF） decreased by 24% and intra-pressure（IP） increased by 66% in CS＋LPS group.The pathological scores of the lung tissues also increased.Compared with CS＋LPS group,no change in the lung function was observed after given NaHS or PPG,but the pathological scores decreased in CS＋ LPS＋ NaHS group.Compared with control group,the content of H2S in plasma was increased by 26% on day 16.Compared with CS＋LPS group,the content of H2S in plasma of CS＋LPS＋PPG group was decreased by 22% after 30 days.Compared with control group,the protein expression of CSE increased,and no statistical difference among CS＋LPS group,CS＋ LPS＋ NaHS group and CS＋LPS＋PPG group was observed.Compared with control group, MDA content in the lung tissues was increased by 24% in CS＋LPS group,the activity of SOD was increased by 47% and the activity of CAT was increased by 52%.Compared with CS＋LPS group,the MDA content in CS＋LPS＋NaHS group was decreased by 21%,and no statistical difference in the activity of SOD and CAT was observed.The activity of SOD decreased by 33% after given PPG.CONCLUSION： H2S plays a role as anti-oxidant in the rats with COPD.The CSE/ H2S pathway may be involved in the development of COPD.