Universidad de Buenos Aires-CONICET, Instituto de Investigaciones Biomédicas (INBIOMED), Buenos Aires, Argentina; Universidad de Buenos Aires, Facultad de Medicina, Departamento de Bioquímica Humana, Buenos Aires, Argentina.
Universidad de Buenos Aires-CONICET, Instituto de Investigaciones Biomédicas (INBIOMED), Buenos Aires, Argentina.
J Steroid Biochem Mol Biol. 2021 Apr;208:105792. doi: 10.1016/j.jsbmb.2020.105792. Epub 2020 Nov 24.
Acyl-CoA synthetase 4 (Acsl4), an enzyme involved in arachidonic acid (AA) metabolism, participates in physiological and pathological processes such as steroidogenesis and cancer. The role of Acsl4 in neurons and in nervous system development has also been documented but little is known regarding its functionality in glial cells. In turn, several processes in glial cells, including neurosteroidogenesis, stellation and AA uptake, are regulated by cyclic adenosine monophosphate (cAMP) signal. In this context, the aim of this work was to analyze the expression and functional role of Acsl4 in primary rat astrocyte cultures and in the C6 glioma cell line by chemical inhibition and stable silencing, respectively. Results show that Acsl4 expression was regulated by cAMP in both models and that cAMP stimulation of steroidogenic acute regulatory protein mRNA levels was reduced by Acsl4 inhibition or silencing. Also, Acsl4 inhibition reduced progesterone synthesis stimulated by cAMP and also affected cAMP-induced astrocyte stellation, decreasing process elongation and increasing branching complexity. Similar effects were observed for Acsl4 silencing on cAMP-induced C6 cell morphological shift. Moreover, Acsl4 inhibition and silencing reduced proliferation and migration of both cell types. Acsl4 silencing in C6 cells reduced the capacity for colony proliferation and neurosphere formation, the latter ability also being abolished by Acsl4 inhibition. In sum, this work presents novel evidence of Acsl4 involvement in neurosteroidogenesis and the morphological changes of glial cells promoted by cAMP. Furthermore, Acsl4 participates in migration and proliferation, also affecting cell self-renewal. Altogether, these findings provide insights into Acsl4 functions in glial cells.
酰基辅酶 A 合成酶 4（Acsl4）是一种参与花生四烯酸（AA）代谢的酶，参与了类固醇生成和癌症等生理和病理过程。Acsl4 在神经元和神经系统发育中的作用也有记载，但关于其在神经胶质细胞中的功能知之甚少。反过来，神经甾体生成、星状化和 AA 摄取等几种胶质细胞过程受环磷酸腺苷（cAMP）信号的调节。在这种情况下，本工作的目的是通过化学抑制和稳定沉默分别分析 Acsl4 在原代大鼠星形胶质细胞培养物和 C6 神经胶质瘤细胞系中的表达和功能作用。结果表明，Acsl4 的表达在两种模型中均受 cAMP 调节，并且 Acsl4 的抑制或沉默降低了 cAMP 对类固醇生成急性调节蛋白 mRNA 水平的刺激。此外，Acsl4 的抑制减少了 cAMP 刺激的孕激素合成，也影响了 cAMP 诱导的星形胶质细胞星状化，减少了突起伸长并增加了分支复杂性。Acsl4 沉默对 cAMP 诱导的 C6 细胞形态转变也产生了类似的影响。此外，Acsl4 的抑制和沉默减少了两种细胞类型的增殖和迁移。C6 细胞中 Acsl4 的沉默减少了集落增殖和神经球形成的能力，而 Acsl4 的抑制也消除了这种能力。总之，本工作提供了 Acsl4 参与神经甾体生成和 cAMP 促进的神经胶质细胞形态变化的新证据。此外，Acsl4 参与迁移和增殖，也影响细胞自我更新。综上所述，这些发现为 Acsl4 在神经胶质细胞中的功能提供了新的见解。
