黄连素通过调控肝脏HNF-4α/miR122通路纠正糖尿病糖脂代谢紊乱机制研究

Improve glucose and lipid metabolism disorder is a key target for the treatment of diabetes and its complications. Berberine was been reported to correct glucose and lipid disorders, but its mechanism of this action, as well as whether there is a crosslink pathway existed in the regulation of glucose and lipid metabolism has not yet been clear. The latest research shows that miR122 as a liver-specific microRNA, subject to the regulation of nuclear factor HNF4α, closely related to the glucose and lipid metabolism. Our preliminary work for the first time proved that berberine can enter the liver cell nucleus, inhibition of nuclear factor HNF4α, PGC-1 of FOXO1 expression, inhibit gluconeogenesis. The present study based on our preliminary work, develope high fat diet combined STZ injection induced type 2 diabetes mice and culture its primary liver cell, target by HNF-4α gene over-expression or silencing joint with the miR122 silence and overexpression, observed the alteration of key enzyme (PEPCK/G6Pase) and key protein of lipid synthesis and metabolism regulation protein (SREBP-1/FAS/ACC-1/CPT-1), reveal the berberine in the treatment of diabetes the target of a direct role to clarify the berberine reversed the glucose and lipid disorders crosstalk pathway for its clinical application to provide a theoretical.

改善糖脂代谢紊乱是治疗糖尿病及其并发症的关键措施。黄连素纠正糖尿病糖脂代谢紊乱已确切，但其作用机制，以及对糖脂代谢的调节作用是否存在串话通路至今尚未清楚。最新研究表明miR122作为肝脏特异性microRNA，受到核因子HNF4α的调控，与糖脂代谢密切相关。课题组前期工作首次证明，黄连素可进入肝细胞核，抑制核因子HNF4α,PGC-1, FOXO1的表达，具有降血脂及抑制糖异生作用。本课题拟在此基础上，在高脂联合STZ诱导小鼠模型及其原代肝细胞培养上，以HNF-4α/miR122为靶点，通过对HNF-4α基因过表达或沉默联合miR122沉默及过表达干预，探讨黄连素对糖异生关键酶（PEPCK/G6Pase），脂质合成及代谢关键蛋白（SREBP-1/FAS/ACC-1/CPT-1）调控作用，揭示黄连素治疗糖尿病的直接作用靶点，阐明黄连素逆转糖尿病糖脂代谢紊乱串话通路，为其临床应用提供理论依据。

2型糖尿病是由于胰岛素分泌紊乱或功能障碍引起的碳水化合物，蛋白质及脂肪代谢紊乱为特征的代谢综合征。糖尿病患者多数还表现为脂质代谢异常，而高脂亦是引起糖尿病致死的糖尿病微血管及大血管病变的主要原因，黄连素纠正糖尿病糖脂代谢紊乱的作用已有报道，课题组前期工作证明，黄连素可进入肝细胞核抑制核因子HNF4α,PGC-1, FOXO1的表达，具有降血脂及抑制糖异生作用，miR122作为肝脏特异性microRNA，受到核因子HNF4α的调控，与糖脂代谢密切相关，在此基础上，本研究拟揭示HNF-4α/miR122可作为对糖脂代谢串话靶点，而黄连素可通过调控该靶点发挥治疗2型糖尿病糖脂代谢紊乱的作用。本研究通过高脂联STZ诱导小鼠模型，通过棕榈酸刺激建立糖脂代谢紊乱细胞模型，并以HNF-4α/miR122为靶点，通过对HNF-4α基因过表达或沉默联合miR122沉默及过表达干预HepG2细胞，探讨黄连素对糖异生关键酶(PEPCK/G6Pase)脂质合成及代谢关键蛋白(SREBP-1/FAS/ ACC-1/CPT-1)调控作用，结果表明，黄连素可治疗高脂联合STZ诱导2型糖尿病小鼠糖脂代谢紊乱，抑制肝脏中HNF-4α,miR122以及糖异生关键酶(PEPCK/G6Pase)脂质合成及代谢关键蛋白(SREBP-1/FAS/ ACC-1/CPT-1)的表达；在细胞水平，通过HNF-4α基因过表达或沉默联合miR122沉默及过表达干预，结果显示，黄连素可抑制2型糖尿病糖脂代谢紊乱，并抑制肝脏中HNF-4α,miR122以及糖异生关键酶(PEPCK/G6Pase)脂质合成及代谢关键蛋白(SREBP-1/FAS/ ACC-1/CPT-1)的表达，细胞干预HNF-4α基因过表达或沉默联合miR122沉默及过表达记过显示，黄连素对糖脂代谢紊乱的调控作用与HNF-4α/miR122及其下游糖异生脂代谢通路有关。揭示黄连素治疗糖尿病的直接作用靶点，阐明黄连素逆转糖尿病糖脂代谢紊乱串话通路，为其临床应用提供理论依据。本研究目前在投SCI 论文2篇，拟2016年6月培养毕业博士研究生1名。