Department of Anesthesiology, Tianjin Medical University General Hospital, No. 154 Anshan Road, Tianjin, 300052, Tianjin, People's Republic of China.
Tianjin Research Institute of Anesthesiology, Tianjin, 300052, Tianjin, People's Republic of China.
Acta Diabetol. 2023 Mar;60(3):387-399. doi: 10.1007/s00592-022-01990-0. Epub 2022 Dec 27.
Diabetic peripheral neuropathy (DPN) is a common diabetic complication. Aberrant mitochondrial function causes neurodegeneration under hyperglycemia-induced metabolic stress, which in turn results in DPN progression. mA and mA reader (YTHDC2) are closely related to diabetes and diabetes complications, while the role of YTHDC2 in regulating mitochondrial metabolism in DPN needs to be further probed.
For HG treatment, Schwann cells (RSC96) were subjected to D-glucose for 72 h. db/db mice were used as the diabetic mouse model. Me-RIP assay was performed to evaluate KDM5B mA level. RNA degradation assay was conducted to examine KDM5B mRNA stability. In addition, OCR and ECAR were examined by XF96 Analyzer. Moreover, the content of ATP and PDH activity in RSC96 cells were detected using kits, and the level of ROS was detected using MitoSOX staining. RIP, RNA pull-down and dual-luciferase reporter gene assays were carried out to verify the binding relationships between YTHDC2, KDM5B and SIRT3.
We first observed that KDM5B expression and KDM5B mRNA stabilization were significantly increased in DPN. The mA reader YTHDC2 was lowly expressed in DPN. Meanwhile, YTHDC2 over expression decreased KDM5B mRNA stability in an mA-dependent manner. Our results also revealed that YTHDC2 overexpression resulted in reduced ROS level and increased ATP level, PDH activity, OCR and ECAR in HG-treated Schwann cells, while these effects were reversed by KDM5B overexpression. Additionally, SIRT3 served as the target of YTHDC2/KDM5B axis in regulating mitochondrial metabolism in DPN.
Taken together, YTHDC2 promoted SIRT3 expression by reducing the stabilization of KDM5B to improve mitochondrial metabolic reprogramming in DPN.
糖尿病周围神经病变（DPN）是一种常见的糖尿病并发症。在高血糖诱导的代谢应激下，异常的线粒体功能导致神经退行性变，进而导致 DPN 进展。mA 和 mA 阅读器（YTHDC2）与糖尿病及其并发症密切相关，而 YTHDC2 在调节 DPN 中线粒体代谢中的作用需要进一步探究。
对 HG 处理的施万细胞（RSC96）进行 72 h 的 D-葡萄糖处理。使用 db/db 小鼠作为糖尿病小鼠模型。进行 Me-RIP 测定以评估 KDM5B mA 水平。进行 RNA 降解测定以检查 KDM5B mRNA 稳定性。此外，通过 XF96 分析仪检查 OCR 和 ECAR。此外，使用试剂盒检测 RSC96 细胞中的 ATP 含量和 PDH 活性，使用 MitoSOX 染色检测 ROS 水平。进行 RIP、RNA 下拉和双荧光素酶报告基因测定以验证 YTHDC2、KDM5B 和 SIRT3 之间的结合关系。
我们首先观察到 DPN 中 KDM5B 表达和 KDM5B mRNA 稳定性显著增加。mA 阅读器 YTHDC2 在 DPN 中表达水平较低。同时，YTHDC2 的过表达以 mA 依赖的方式降低 KDM5B mRNA 的稳定性。我们的结果还表明，YTHDC2 过表达导致 HG 处理的施万细胞中 ROS 水平降低，ATP 水平、PDH 活性、OCR 和 ECAR 增加，而这些作用被 KDM5B 过表达逆转。此外，SIRT3 是 YTHDC2/KDM5B 轴在调节 DPN 中线粒体代谢中的作用靶点。
综上所述，YTHDC2 通过降低 KDM5B 的稳定性来促进 SIRT3 的表达，从而改善 DPN 中线粒体代谢的重编程。
