摘要
目的 探讨胰岛素治疗对2型糖尿病状态下脂肪细胞的色素上皮衍生因子（PEDF）表达的影响.方法 对22例初诊2型糖尿病患者进行为期2周的胰岛素强化治疗,分析比较其治疗前后空腹血糖、血甘油三酯及PEDF水平变化.对8周龄雄性SD大鼠进行高脂饮食喂养联合小剂量链脲佐菌素诱导,建立2型糖尿病大鼠模型,随机数字表法分为糖尿病组、胰岛素治疗组、格列齐特治疗组,另设正常饮食对照组.分化成脂的3T3-L1脂肪细胞加入肿瘤坏死因子-α（TNF-α）和（或）胰岛素干预24h.用实时定量逆转录聚合酶链反应（qRT-PCR）和免疫印迹法（Western印迹）检测脂肪组织或细胞PEDF表达水平,用酶联免疫吸附法（ELISA）测定血清或脂肪细胞培养液上清中PEDF的含量.将3T3-L1脂肪细胞分为对照组、PEDF处理组、抗PEDF抗体处理组,测定各组脂肪细胞对3H-葡萄糖的摄取率.结果 2型糖尿病患者胰岛素治疗后,空腹血糖与血甘油三酯均显著下降[（12.9±2.8）与（5.9±1.4） mmol/L、（3.1±1.8）与（1.7±0.8） mmol/L,P＜0.05],并有血清PEDF水平明显降低[（22.85±5.73）与（18.38±5.28） mg/L,P＜0.05].糖尿病大鼠血清PEDF水平高于对照组和胰岛素治疗组[（28.6±0.5）、（25.4±0.6）、（25.3±0.6） μg/L,P＜0.05],并伴有脂肪组织PEDF、TNF-α的mRNA及蛋白表达升高（P＜0.05）,胰岛素治疗后上述指标均下降（P＜0.05）,但在格列齐特组并无明显改善.进一步实验发现,TNF-α诱导3T3-L1脂肪细胞PEDF表达及分泌增多（P＜0.05）,而该作用可被胰岛素减弱（P＜0.05）.此外,PEDF下调3T3-L1脂肪细胞葡萄糖摄取率的作用可被抗PEDF抗体拮抗（P＜0.05）.结论 胰岛素可下调2型糖尿病状态下脂肪细胞及血清中PEDF的表达,改善脂肪细胞的葡萄糖摄取率,这可能是胰岛素治疗改善胰岛素抵抗的机制之一.
Objective To explore the effects of insulin therapy on the expression of pigment epithelium-derived factor （PEDF） in adipocytes of type 2 diabetic mellitus （T2DM） in rats.Methods A total of 22 newly diagnosed type 2 diabetics received a 2-week intensive insulin therapy.The levels of fasting plasma glucose （FPG）,serum triglyceride and PEDF were measured before and after therapy.T2DM was induced by a high-fat diet and a low-dose streptozotocin （STZ）.The Spraque-Dawley rats were divided randomly into diabetic,insulin treatment and gliclazide treatment groups.Another group with a chow diet was designated as normal controls.Differentiated 3T3-L1 adipocytes were then incubated with tumor necrosis factor-alpha （TNF-α） and（or） insulin for 24 h.Quantitative reverse transcription-polymerase chain reaction （qRT-PCR） and Western blot were used to detect the expression of PEDF in adipose tissue or adipocytes.The PEDF levels in both sera and cell supernatant were measured by enzyme-linked immunosorbent assay （ELISA）.Glucose uptake was detected after treatment of PEDF or anti-PEDF antibody simultaneously together with insulin in mature 3T3-L1 adipocytes.Results Insulin therapy decreased the serum levels of FPG and triglyceride of T2DM patients （（12.9 ± 2.8） vs（5.9 ± 1.4） mmol/L,（3.1 ± 1.8） vs（1.7 ±0.8） mmol/L,P 〈 0.05） while the serum level of PEDF decreased significantly after therapy （（22.85 ±5.73） vs （18.38 ± 5.28） μg/L,P 〈 0.05）.Consistently the serum level of PEDF of diabetic rats was remarkably higher than that of normal controls and insulin-treated group （（28.6 ± 0.5） vs （25.4 ± 0.6）and （25.3 ±0.6） μg/L,P 〈 0.05）.And the elevated levels of PEDF,TNF-α mRNA and protein in adipose tissue （P 〈 0.05） could be reduced by insulin treatment （P 〈 0.05）.However,no obvious change was detected in gliclazide treatment group.Further evidences suggested that TNF-α could induce more secretion and expression of PEDF in 3T3-L1 a
出处
《中华医学杂志》
CAS
CSCD
北大核心
2014年第38期2992-2995,共4页
National Medical Journal of China
基金
国家自然科学基金青年基金（81370909、81300705、30900506）
广东省自然科学基金（S2012010008914）
中央高校基本科研业务费专项资金（12ykpy41）
南京市医学重点科技发展项目（ZKX11017）
关键词
胰岛素
糖尿病
2型
色素上皮衍生因子
脂肪细胞
Insulin
Diabetes mellitus, type2
Pigment epithelium-derived factor
Adipocyte
