牛磺酸对STZ诱导的糖尿病大鼠伤口愈合的影响

Effect of taurine on wound healing in diabetic rats induced by streptozotocin

目的:探讨牛磺酸对糖尿病大鼠伤口愈合的影响。方法:雄性SD大鼠随机分为对照组(CON)、模型组(MOD)及牛磺酸处理组(TAU)。通过腹腔注射链脲佐菌素(STZ)70 mg/kg建立糖尿病模型。成模2周后,将各组大鼠背部剃毛并剪一直径为2 cm的切口。牛磺酸处理组大鼠给予牛磺酸治疗。观测各组大鼠伤口愈合情况,3周后,收集血样品,处死大鼠并收集伤口肉芽组织。肉芽组织苏木精-伊红(H-E)染色切片观察肉芽组织形态学变化;Masson切片染色观察胶原表达;ELISA试剂盒检测血清中血管内皮生长因子(VEGF)及血小板源性生长因子(PDGF)的水平,Western blot检测肉芽组织中VEGF表达及VEGFR、ERK和Akt的磷酸化水平。结果:模型组大鼠伤口愈合速率较对照组变慢,血清VEGF及PDGF水平降低;模型组大鼠伤口组织VEGF表达及VEGFR、ERK和Akt的磷酸化水平均低于对照组。牛磺酸处理加速伤口愈合,改善血清中血管生成因子VEGF及PDGF水平。牛磺酸治疗增加肉芽组织中VEGF表达,并提高组织中VEGFR、ERK和Akt的磷酸化水平。组织形态学显示,牛磺酸能促使肉芽组织中的胶原有序排列,且增加肉芽组织中小血管的生成。结论:牛磺酸可通过促进糖尿病大鼠伤口肉芽组织中血管生成加速伤口愈合。

Objective:To observe effect of taurine on wound healing in diabetic rats.Methods:Male SD rats were randomized into control group(CON),model group(MOD) and taurine treatment group(TAU).Diabetic rat models were induced by an intraperitoneal injection of streptozotocin(STZ,70 mg/kg).Rats were shaved and excised a circular wound(2.0 cm in diameter) with full thickness on the dorsum skin after diabetic models were confirmed for 2 weeks.Rats in TAU group were treated with taurine,and those in CON and MOD groups were managed with vaseline.The wound area was checked in individual rat.After 3 weeks of administration,blood samples were collected to determine serum vascular endothelial growth factor(VEGF) and platelet derived growth factor(PDGF) levels.Granulation tissues were obtained to detect VEGF expression,and phosphorylated VEGF receptor,ERK and Akt levels,as well as sectioned by thickness of 5 μm and stained by hematoxylin and eosin(H-E) and Masson trichrome for observing morphological change and collagen expression.Results:Wound healing rate as well as serum VEGF and PDGF levels was significantly slowed down and decreased in MOD group than in CON group.Treatment with taurine significantly improved the rate of wound healing,and increased serum levels of VEGF and PDGF in TAU group compared with the MOD.Further,taurine enhanced expression of VEGF and levels of phosphorylated VEGF receptor,ERK and Akt in granulation tissues of the TAU rats compared to the MOD.Histological observation showed that taurine alleviated inflammation,and the skin structure was clearly observed in the wounds in TAU group,with collagen being regularly arranged and significantly increased number of small blood vessels in the granulation tissues.Conclusion:The results suggest that taurine can promote wound healing in diabetic rats by improvement of angiogenesis.