Sun Haoxiang, Tan Ruixiang, Sun Yongzhi, Li Yimeng, Xie Ying, Zhang Cheng, Song Jianping, Zhu Wei, Zhou Jiuyao, Deng Changsheng, Mei Manxue
Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China.
Sci-Tech Industrial Park, Guangzhou University of Chinese Medicine, Guangzhou, China.
Front Pharmacol. 2025 Apr 29;16:1563201. doi: 10.3389/fphar.2025.1563201. eCollection 2025.
The incidence of diabetes is rising annually, significantly impacting public health and imposing a substantial economic burden on society. Ophiopogonin D (Op D) exhibits certain hypoglycemic effects; however, its mechanisms remain unclear.
β-cell dedifferentiation, distinct from β-cell apoptosis, is a pathogenic mechanism we aim to explore regarding Op D's regulatory effects. We established an animal model of β-cell dedifferentiation to assess Op D's impact on glucose tolerance, blood glucose levels, and insulin secretion. We employed immunohistochemistry and immunofluorescence to analyze the expression levels of dedifferentiation-related proteins. Additionally, we created an β-cell dedifferentiation model using INS-1 cells to evaluate Op D's influence on insulin secretion and dedifferentiation. Transcriptomic analysis was conducted to explore potential mechanisms by which Op D ameliorates dedifferentiation, with further validation via Western blotting and immunofluorescence. Flow cytometry, fluorescence microscopy, and related assays were used to assess Op D's effects on oxidative stress. Endoplasmic reticulum (ER) tracing agents marked the ER, and laser confocal microscopy examined ER morphology, with ER stress inducers and inhibitors employed to clarify Op D's mechanisms.
Results indicated that Op D reduced blood glucose levels, improved glucose tolerance, enhanced insulin secretion, mitigated pancreatic atrophy, and increased PDX1 and FOXO1 expression levels. Furthermore, Op D inhibited ER stress, decreased GRP78 expression, reduced NGN3 levels, elevated PDX1, NKX6.1, and MAFA expression, and decreased oxidative stress-related products (ROS, MDA) while increasing SOD and GSH levels.
These findings demonstrate that Op D can improve β-cell dedifferentiation by modulating the GRP78/ROS/PDX1 pathway to inhibit ER stress.
糖尿病的发病率逐年上升，对公众健康产生重大影响，并给社会带来沉重的经济负担。麦冬皂苷D（Op D）具有一定的降血糖作用，但其作用机制尚不清楚。
β细胞去分化不同于β细胞凋亡，是我们旨在探索Op D调节作用的致病机制。我们建立了β细胞去分化动物模型，以评估Op D对葡萄糖耐量、血糖水平和胰岛素分泌的影响。我们采用免疫组织化学和免疫荧光分析去分化相关蛋白的表达水平。此外，我们使用INS-1细胞创建了β细胞去分化模型，以评估Op D对胰岛素分泌和去分化的影响。进行转录组分析以探索Op D改善去分化的潜在机制，并通过蛋白质印迹和免疫荧光进一步验证。使用流式细胞术、荧光显微镜和相关检测方法评估Op D对氧化应激的影响。内质网（ER）示踪剂标记内质网，激光共聚焦显微镜检查内质网形态，使用内质网应激诱导剂和抑制剂阐明Op D的作用机制。
结果表明，Op D降低了血糖水平，改善了葡萄糖耐量，增强了胰岛素分泌，减轻了胰腺萎缩，并提高了PDX1和FOXO1的表达水平。此外，Op D抑制内质网应激，降低GRP78表达，降低NGN3水平，提高PDX1、NKX6.1和MAFA表达，并减少氧化应激相关产物（ROS、MDA），同时提高SOD和GSH水平。
这些发现表明，Op D可以通过调节GRP78/ROS/PDX1途径来改善β细胞去分化，从而抑制内质网应激。
