柚皮苷通过抑制瘦素通路对抗高糖引起的心肌细胞损伤

Naringin protects against high glucose-induced injury by inhibiting leptin pathway in H9c2 cardiac cells

目的：探讨柚皮苷能否通过抑制瘦素通路保护H9c2心肌细胞，对抗高糖HG引起的损伤。方法：应用Westernblotting法检测瘦素及瘦素受体（LEPR）的表达水平；细胞计数盒（CCK-8）测定细胞存活率；Hoechst33258核染色荧光显微镜照相测定凋亡细胞的形态及数量的变化；双氯荧光素（DCFH-DA）染色荧光显微镜照相法检测胞内活性氧（ROS）水平；罗丹明123染色法测定线粒体膜电位（MMP）。结果：应用35mmol／L葡萄糖（HG）处理H9c2心肌细胞6～24h能上调瘦素表达，其中9h时表达最多；HG处理心肌细胞1-24h也能促进LEPR表达，其中12h时表达最多；在HG处理心肌细胞前，80μmol／L柚皮苷预处理2h能明显抑制HG对瘦素及LEPR表达的上调作用；柚皮苷预处理2h、瘦素拮抗剂预处理24h或瘦素受体拮抗剂预处理2h均能抑制HG引起的心肌细胞损伤，使细胞存活率增多，凋亡细胞数量和胞内ROS生成减少，MMP回升。结论：柚皮苷可通过抑制瘦素通路保护H9c2心肌细胞，对抗HG引起的损伤。

AIM： To study whether naringin protects H9c2 cardiac cells against high glucose （HG）-induced injury by inhibiting the leptin pathway. METHODS： The expression levels of leptin and leptin receptor （LEPR） were de- tected by Western blotting. The cell viability was analyzed by CCK-8 assay. The changes of the morphology and the number of apoptotic cells were tested by Hoeehst 33258 nuclear staining. The intracellular levels of reactive oxygen species （ROS） were measured by DCFH-DA staining. Mitoehondrial membrane potential （MMP） was determined by rhodamine 123 stai- ning. RESULTS： Treatment of the ceils with 35 mmol/L glucose （HG） for 6 ～ 24 h up-regulated the expression of leptin in H9e2 cardiac cells with the peak value at 9 h. Treatment of the cells with HG for 1 - 24 h also enhanced the expression of LEPR, peaking at 12 h. Pretreatment with 80 Ixmol/L naringin for 2 h before exposure of the H9c2 cardiac cells to HG significantly inhibited the up-regulation of both leptin and LEPR induced by HG. Pretreatment of the cells with naringin for 2 h, leptin antagonist for 24 h, or leptin receptor antagonist for 2 h attenuated HG-induced injury in the cardiomyocytes, evidenced by an increase in cell viability, decreases in the number of apoptotie cells and intracellular ROS production as well as a recovery of MMP. CONCLUSION： Naringin may protect the cardiomyocytes against the HG-induced injury by inhibition of the leptin pathway.