CAJ | 학술논문

目的探讨肿瘤坏死因子α(TNF-α)诱导的胰岛素抵抗(IR)对糖脂代谢及脂肪甘油三酯水解酶(ATGL)的影响.方法健康雄性C57BL/6J小鼠随机分为2组,分别给予腹腔注射TNF-α6μg·kg-1·d-1(TNF组,20只)和等体积生理盐水(NC组,20只)共7 d.采用2-脱氧-3H葡萄糖(2-DOG)为示踪剂的扩展胰岛素钳夹技术评价小鼠胰岛素敏感性和糖代谢变化,用逆转录聚合酶链反应(RT-PCR)和蛋白质印迹法分别测定代谢相关基因ATGL、激素敏感性脂酶(HSL)、过氧化物酶体增殖物激活受体γ(PPARγ)等组织mRNA或血浆蛋白表达水平的变化.结果 TNF-α处理后,小鼠空腹血糖(FBG)、血浆胰岛素和游离脂肪酸(FFA)水平均增高.在胰岛素钳夹术中,TNF组血浆胰岛素水平明显高于NC组[(341.7±17.7)vB(84.7±5.5)mU/L,P＜0.01],胰岛素对FFA的抑制作用明显障碍[FFA,TNF组:(0.82±0.03)mmol/L,NC组:(0.43±0.07)mmol/L,P＜0.01].TNF组葡萄糖输注率(GIR)明显低于NC组[(39.1±2.3)vs(54.2±2.2)mg·kg-1·min-1,P＜0.01],骨骼肌葡萄糖摄取率(MGU)也明显低于NC组[(15.8±1.7)vs(20.9±2.5)μmol·100 g-1·min-1,P＜0.01].TNF组脂肪组织ATGL mRNA表达明显低于对照组(0.85±0.09 vs 1.37±0.12,P＜0.01),ATGL蛋白水平也明显低于对照组(0.53±0.03 vs 0.65±0.05,P＜0.05).TNF组小鼠脂肪组织PPARγ/mRNA表达明显低于对照组(0.83±0.07 vs 1.07±0.07,P＜0.05).结论在TNF-α诱导的IR中,ATGL在脂代谢相关通路中起着调控作用.
목적 탐토종류배사인자α(TNF-α)유도적이도소저항(IR)대당지대사급지방감유삼지수해매(ATGL)적영향.방법 건강웅성C57BL/6J소서수궤분위2조,분별급여복강주사TNF-α6μg·kg-1·d-1(TNF조,20지)화등체적생리염수(NC조,20지)공7 d.채용2-탈양-3H포도당(2-DOG)위시종제적확전이도소겸협기술평개소서이도소민감성화당대사변화,용역전록취합매련반응(RT-PCR)화단백질인적법분별측정대사상관기인ATGL、격소민감성지매(HSL)、과양화물매체증식물격활수체γ(PPARγ)등조직mRNA혹혈장단백표체수평적변화.결과 TNF-α처리후,소서공복혈당(FBG)、혈장이도소화유리지방산(FFA)수평균증고.재이도소겸협술중,TNF조혈장이도소수평명현고우NC조[(341.7±17.7)vB(84.7±5.5)mU/L,P＜0.01],이도소대FFA적억제작용명현장애[FFA,TNF조:(0.82±0.03)mmol/L,NC조:(0.43±0.07)mmol/L,P＜0.01].TNF조포도당수주솔(GIR)명현저우NC조[(39.1±2.3)vs(54.2±2.2)mg·kg-1·min-1,P＜0.01],골격기포도당섭취솔(MGU)야명현저우NC조[(15.8±1.7)vs(20.9±2.5)μmol·100 g-1·min-1,P＜0.01].TNF조지방조직ATGL mRNA표체명현저우대조조(0.85±0.09 vs 1.37±0.12,P＜0.01),ATGL단백수평야명현저우대조조(0.53±0.03 vs 0.65±0.05,P＜0.05).TNF조소서지방조직PPARγ/mRNA표체명현저우대조조(0.83±0.07 vs 1.07±0.07,P＜0.05).결론 재TNF-α유도적IR중,ATGL재지대사상관통로중기착조공작용.
Objective To investigate the effects of tumor necrosis factor (TNF)-α induced insulin resistance (IR) on glucose and lipid metabolism and adipose triglyceride lipase (ATGL). Methods Forty male C57BL/6J mice were randomly divided into 2 equal groups: TNF-α group with undergoing intraperitoneal injection of TNF-α 6 μg · kg-1·d-1 for 7 days and normal control (NC) group with saline injection. Hyperinsulinemic-euglycemic clamp technique combined with 2-deoxy-[3H] glucose as a tracer was used on 20 mice, 10 from each group, to examine the fasting blood glucose (FBG), plasma insulin (INS), total cholesterol (TC), triglyceride (TG), and free fatty acid (FFA). The glucose infusion rate (GIR) was recorded. Other 20 mice, 10 in each group, were killed with their adipose and/or muscle tissues taken out. RT-PCR was used to detect the Mrna expression of ATGL, hormone-sensitive lipase (HSL), carnitine palmitoyl transferase-1 (CPT-1), and peroxisome proliferator activated receptor-γ (PPARγ). Western blotting was used to measure the protein expression of ATGL. Muscle glucose uptake (MGU) was measured. Results After TNF-α treatment, the FBG, plasma INS, and FFA were significantly elevated in the TNF group compared with the NC group (all P＜0.05). During the steady-state of clamp test, the plasma INS level of the TNF group was (341.7 ± 17.7) Mu/L, significantly higher than that of the NC group [(84.7±5.5) Mu/L,P＜0.01]. The FFA level of the TNF group was (0. 82±0.03) mmol/L, significantly higher than that of the NC group [(0.43±0.07) mmol/L,P＜0.01] . The GIR of the TNF group was (39.1±2.3) mg·kg-1·min-1 ,significantly lower than that of the NC group [ (54.2±2.2) mg · kg-1 . Min-1 ,P＜0.01]. The MGU level of the TNF group was (15.8 ± 1.7) μmol · 100 g-1 min-1, significantly lower than that of the NC group [(20.9 ± 2.5)μ mol · 100 g-1 min-1, p＜0.01]. The ATGL Mrna expression level in adipose tissues of the TNF group was (0. 85 ± 0. 09), significantly lower than that of the NC group (1.37±0.12, P＜0.01). The ATGL protein expression level of the TNF group was 0.53 ± 0.03, significantly lower than that of the NC group (0.65 ± 0.05, P＜0.05). The PPARγ Mrna expression level in adipose tissues of the TNF group was 0.83 ± 0.07, significantly lower than that of the NC group (1.07 ± 0.07, P＜0.05). Conclusion In TNF-α induced insulin resistance, AGTL may be involved in the pathways of lipid metabolism.