组蛋白去乙酰化酶2在帕金森病中的作用及机制研究

Study on the role and mechanism of histone deacetylase 2 in Parkinson's disease

摘要:

目的 旨在探究组蛋白去乙酰化酶2（HDAC2）通过类甲基化转移酶3（METTL3）/细胞因子信号抑制因子3（SOCS3）轴调控帕金森病（PD）中神经元死亡的作用机制。方法 SH-SY5Y细胞分组：Control组、MPP⁺组、MPP⁺+HDAC2抑制剂组、MPP⁺+HDAC2抑制剂+sh-NC组、MPP⁺+HDAC2抑制剂+sh-METTL3组。观察各组细胞在细胞死亡、细胞活性、HDAC2、METTL3、SOCS3、组蛋白H3赖氨酸18乳酸化（H3K18la）方面的差异。比较oe-NC组及oe-METTL两组SOCS3的m6A修饰水平、METTL3在SOCS3上的富集程度、METTL3表达、SOCS3表达、SOCS3 mRNA稳定性。结果 MPP⁺ 组与Control组相比，HDAC2基因和蛋白相对表达量升高（P <0.05），细胞死亡率升高（P <0.05），细胞活性及H3K18la在METTL3上的富集程度降低（P <0.05），METTL3、H3K18la、SOCS3均下调（P <0.05）。MPP⁺+HDAC2抑制剂组与MPP⁺组相比，细胞死亡率降低（P <0.05），细胞活性及H3K18la在METTL3上的富集程度升高（P <0.05），METTL3、H3K18la、SOCS3上调（P <0.05）。MPP⁺+HDAC2抑制剂+sh-NC组与MPP⁺+HDAC2抑制剂组在细胞死亡率、细胞活性、METTL3表达、SOCS3表达上无差异（P >0.05）。MPP⁺+HDAC2抑制剂+sh-METTL3组与MPP⁺+HDAC2抑制剂+sh-NC组相比，细胞死亡率升高（P <0.05），细胞活性降低（P <0.05），METTL3及SOCS3表达下调（P <0.05）。Oe-METTL3与oe-NC组比较，SOCS3的m6A修饰水平及METTL3在SOCS3上的富集程度升高（P <0.05），METTL3及SOCS3升高（P <0.05），SOCS3 mRNA稳定性升高（P <0.05）。结论 在PD中HDAC2通过诱导METTL3组蛋白去乳酸化抑制METTL3表达，这一机制引起SOCS3的m6A修饰水平降低，并导致SOCS3表达下调，进而促进PD发病。

关键词:帕金森病;组蛋白去乙酰化酶2;类甲基化转移酶3;细胞因子信号抑制因子3

Abstract:

Objective To explore the role of histone deacetylase 2 (HDAC2) in modulating the neuron death during Parkinson's disease (PD) via methyltransferase-like 3 (METTL3) / suppressor of cytokine signaling 3 (SOCS3) axis.Methods SH-SY5Y cells were divided into: control, MPP⁺, MPP⁺ + HDAC2 inhibitor, MPP⁺ + HDAC2 inhbitor + sh-NC and MPP⁺ + HDAC2 inhibitor + sh-METTL3 group, and the alterations in cell death, cell vibility, HDAC2, METTL3, SOCS3 and the lacylation of Lsy in histone 3 (H3K18la) were compared; oe-NC and oe-METTL3 group, and the differences in SOCS3, m6A-modified SOCS3, METTL3 and the enrichment of METTL3 in SOCS3 between the two groups were compared.Results Compared to control group, MPP⁺ group showed the enhancement of cell death and HDAC2, the decline in METTL3, H3K18la, SOCS3, cell viability and enrichment of H3K18la in METTL3 (P < 0.05). Compared to MPP⁺ group, MPP⁺ + HDAC2 inhibitor group displayed the decreases of cell death, and the increases of METTL3, H3K18la, SOCS3, cell viability and enrichment of H3K18la in METTL3 (P < 0.05). There were no significant changes in cell death, METTL3, SOCS3 and cell viability between MPP⁺ + HDAC2 inhibitor and MPP⁺ + HDAC2 inhbitor + sh-NC group (P > 0.05). Compared to MPP⁺ + HDAC2 inhbitor + sh-NC group, MPP⁺ + HDAC2 inhibitor + sh-METTL3 group showed the elevation of cell death, and the reduction of METTL3, SOCS3 and cell viability (P < 0.05). Compared to oe-NC group, oe-METTL3 group developed the rise in METTL3, SOCS3, SOCS3 stability, m6A-modified SOCS3 and enrichment of METTL3 in SOCS3 (P < 0.05).Conclusion In PD, HDAC2 inhibited METTL3 via inducing the de-lactylation of METTL3, which led to the decrease of m6A-modified SOCS3 and SOCS3 expression. Downregulation of SOCS3 contributed to the occurrence of PD.

Key words:Parkinson's disease;histone deacetylase 2;methyltransferase-like 3;suppressor of cytokine signaling 3