高糖环境下GLO1对ADSC促损伤血管再内皮化的作用机制研究

Adipose derived stem cell (ADSC) plays a role in promoting re-endothelialization of injured arteries to restore endothelial dysfunction and injury, which shows a wide prospect of clinical application in treating and preventing restenosis and thrombosis after angioplasty. However, methylglyoxal(MG) and Advanced glycation end products accumulated in the hyperglycaemic environment, which could inhibit the ADSC abilities of the survival, migration and differentiation capacity, which is the key to affecting the treatment effect.Glyoxalase 1(GLO1) is restrict enzymes of glyoxalase pathway for cell detoxication. GLO1 is closely related to cell functional protection and apoptosis pathway. Our previous research showed very low expression of GLO1 in diabetic rat’s ADSC and overexpression of GLO1 can restore the impaired survival, migration and improve proangiogenic ability of ADSC caused by hyperglycarmiai,but the effect of promoting re-endothelialization is unclear. Thus we propose a hypothesis thatGLO1 overexpression ADSC may restore the impaired survival, migration and improve re-endothelialization ability caused by hyperglycarmia and diabetes. In this study, lentiviral transfection and other technologies will be adopted to regulate diabetic ADSC-GLO1 expression, evaluate the GLO1 overexpression for ADSC survival, migration,homing,differentiation in hyperglycaemic environment. In vivo, diabetic rat model of carotid artery injury is applied to explore the affection of GLO1 on ADSC promoting re-endothelialization. The associatedERK/NF-κB/Bax/Bcl2 signal pathway will be studied. This study will bring new insights into the treatment of restenosis and thrombosis after angioplasty especially for patients with diabetes.

脂肪干细胞(ADSC)移植可促进损伤血管早期再内皮化,防治血管重建术后血栓形成和再狭窄。但高糖下甲基乙二醛(MG)及晚期糖基化终产物(AGEs)积聚显著抑制ADSC增殖分化。乙二醛酶1(GLO1)是MG解毒限速酶,对细胞功能保护及抗凋亡有重要作用。前期研究发现糖尿病ADSC中GLO1表达极低,过表达GLO1后ADSC促缺血组织血管新生能力改善,但其对损伤血管再内皮化的作用及机制尚不明确。因此我们假设:过表达GLO1可抑制凋亡保护高糖下ADSC的存活及促损伤血管再内皮化。本课题拟应用慢病毒转染/基因沉默技术调节GLO1表达水平,进一步研究其对糖尿病ADSC增殖、迁移、分化、凋亡等功能的影响;运用糖尿病小鼠颈动脉内皮损伤模型,研究GLO1对ADSC促损伤血管再内皮化的作用,并探索ERK/NF-κB/Bax/Bcl2通路变化,为提高糖尿病ADSC治疗效率,防治术后血栓形成和再狭窄提供新思路。

脂肪干细胞(ADSC)移植可促进损伤血管早期再内皮化,防治血管重建术后血栓形成和再狭窄。但高糖下甲基乙二醛(MG)及晚期糖基化终产物(AGEs)积聚显著抑制ADSC增殖分化。乙二醛酶1(GLO1)是MG解毒限速酶,对细胞功能保护及抗凋亡有重要作用。前期研究发现糖尿病ADSC中GLO1表达极低,过表达GLO1后ADSC促缺血组织血管新生能力改善,但其对损伤血管再内皮化的作用及机制尚不明确。因此我们假设:过表达GLO1可抑制凋亡保护高糖下ADSC的存活及促损伤血管再内皮化。本课题应用慢病毒转染使ADSC过表达GLO1,体外证实G-ADSC促进ADSC增殖、迁移、分化为内皮细胞、抑制ADSC凋亡的作用，并且成功构建糖尿病小鼠颈动脉内皮损伤模型,体内移植G-ADSC，证实G-ADSC体内促进损伤血管再内皮化,最后发现相关信号通路ERK/Bcl-2表达上调，NF-kB/Bax表达下调。同时我们发现G-ADSC分泌的外泌体G-ADSC-Exo对高糖下的内皮细胞增殖、迁移、成管具有促进作用，本研究的结果为提高糖尿病ADSC的治疗效率, 防治术后动脉血栓形成和再狭窄提供了理论基础及新思路。