链脲菌素诱导型糖尿病猪主动脉内膜炎症因子的检测

Analysis of inflammatory cytokines in aortic intima of pigs with streptozotocin-induced diabetes

目的运用链脲菌素(STZ)诱导制作中国贵州小型猪糖尿病模型,检测主动脉血管壁炎症因子水平,评估模型的血管病变。方法20头中国贵州小型猪分成STZ诱导型糖尿病组(n=10):使用125 mg/kg STZ诱导致病;正常对照组(n=10):注射等量柠檬酸钠溶液。两组分别在制模前和制模1个月后进行了口服葡萄糖耐量试验(OGTT);并于制模前和制模6个月后检测肝肾功能、血脂和外周血白细胞计数。采用免疫组化法检测胰岛β细胞;Western blotting法检测主动脉内膜组织培养液中TNF-α浓度;RT-PCR法测定主动脉内膜TNF-α、IL-1β、IL-6 mRNA水平。结果制模前后两组血清生化指标(除空腹血糖外)无统计学差异(P>0.05)。糖尿病组在诱导后1个月的空腹血糖和餐后2 h血糖水平均显著高于诱导前水平(P<0.001)。糖尿病组胰腺胰岛β细胞几乎消失,组织培养液中TNF-α水平较对照组显著上调(P<0.001),主动脉内膜组织中TNF-α、IL-1β和IL-6mRNA水平也较对照组显著增高(P<0.05)。结论用STZ诱导成功建立了中国贵州小型猪糖尿病模型,糖尿病猪的主动脉管壁内炎症因子水平增高,动脉粥样硬化进展。

Objective To analyze the inflammatory cytokines in aortic wall in Chinese Guizhou minipigs with streptozotocin （STZ） -induced diabetes. Methods Twenty Chinese Guizhou minipigs were divided into STZ （125 mg/kg） -induced diabetic group （n=10） and control group （by injection of same amount of sodium citrate, n=10）. Oral glucose tolerance test （OGTT） was performed before and one month after STZ administration. Liver and renal function, blood lipids and peripheral white blood cell count were evaluated at baseline and 6 months after STZ induction. Pancreas was examined immunohistoehemieally for islet β cells. Aortic intima of diabetic minipigs and controls was analyzed for TNF-ct level in tissue conditioned medium by Western blotting. TNF-ct, IL-1β and IL-6 mRNA levels in aortic intima were assayed by reverse transcription polymerase chain reaction （RT-PCR）. Results There were no significant changes in biochemical parameters before and after the model establishment in both groups （ P〉0.05 ） , except fasting glucose. Significant elevation in fasting glucose and 2-hour postprandial glucose levels was observed one month after STZ induction （ P〈 0. 001 ）. Pancreatic islet β cells in diabetic minipigs had almost disappeared. There was dramatically increased TNF-α level in aotie intima conditioned medium （ P 〈 0. 001 ）, and significant elevation of TNF-α, IL-1β and IL-6 mRNA levels was revealed （ P 〈 0. 05 ）. Conclusion The present study has established Chinese Guizhou minipig models with STZ-indueed diabetes. Inflammatory eytokines significantly elevate in aortic intima of diabetic minipigs, indicating the development of atheroselerosis.