Multiple sclerosis (MS) is characterized by neuroinflammation and neurodegeneration, whose precise processes are not fully understood. Diacylglycerol kinase (DGK) isozymes of α, β, γ and ζ expressed abundantly in the brain and/or the immune system, may be regulatory targets for MS. In this study, we analyzed the four DGK isozymes along the induction, peak and recovery phases in an experimental autoimmune encephalomyelitis (EAE) rat model of MS. The expression of these DGK isozymes and the diacylglycerol (DAG) pathway in the EAE rat brainstems were analyzed by qRT-PCR, immunohistochemistry, immunofluorescence double staining, western blotting and ELISA. Our results showed that the mRNA content of the four DGK isozymes decreased significantly, and their immunoreactivity in myelin sheathes (DGKα, β) and neurons (DGKγ, ζ) became weaker at the beginning of the induction phase. With the progressive increase in clinical signs, DGKα, DGKγ and DGKζ mRNA increased and DGKβ mRNA decreased, and microglia were involved in the formation of perivascular cuffing. In the peak phase, both DGKα and DGKζ were expressed in neurons and inflammatory cells, and DGKζ was also positive in microglia. During the recovery phase, the mRNA content and immunoreactivity of these DGK isozymes generally reached normal levels. Moreover, our results revealed that changes in DAG accumulation and PKCδ phosphorylation were almost the same as those of DGKα and DGKζ mRNA. In summary, the four DGK isozymes are involved in the EAE process. The predominant and broad presence of DGKα and DGKζ suggests that they may regulate the pathological process by attenuating DAG/PKCδ pathway signaling during EAE evolution.

多发性硬化症 (MS) 的特点是神经炎症和神经退行性变，其确切过程尚不完全清楚。α、β、γ 和 ζ 的二酰基甘油激酶 (DGK) 同工酶在大脑和/或免疫系统中大量表达，可能是 MS 的调节靶点。在本研究中，我们分析了 MS 实验性自身免疫性脑脊髓炎 (EAE) 大鼠模型中诱导期、峰值期和恢复期的四种 DGK 同工酶。通过qRT-PCR、免疫组织化学、免疫荧光双染色、蛋白质印迹和ELISA分析这些DGK同工酶和EAE大鼠脑干中二酰基甘油（DAG）途径的表达。我们的结果表明，四种 DGK 同工酶的 mRNA 含量显着降低，它们在髓鞘（DGKα，β）和神经元（DGKγ，ζ）在感应阶段开始时变弱。随着临床体征的进行性增加，DGKα、DGKγ和DGKζ mRNA增加，DGKβ mRNA减少，小胶质细胞参与了血管周围套囊的形成。在高峰期，DGKα和DGKζ均在神经元和炎症细胞中表达，DGKζ在小胶质细胞中也呈阳性。在恢复阶段，这些DGK同工酶的mRNA含量和免疫反应性普遍达到正常水平。此外，我们的结果表明，DAG 积累和 PKCδ 磷酸化的变化与 DGKα 和 DGKζ mRNA 的变化几乎相同。总之，四种 DGK 同工酶参与了 EAE 过程。