Department of Spine Surgery, Liaocheng People's Hospital, China.
Department of Orthopedic Surgery, Liaocheng 3rd People's Hospital, China.
Adv Clin Exp Med. 2019 Jan;28(1):85-94. doi: 10.17219/acem/76749.
MiR-494 is reported to act as a tumor-suppressive factor that inhibits the proliferation and colony formation of some cancer cells. However, there is still no report available on miR-494 functions in spinal cord injury (SCI) until now.
The objective of this study was to examine the status of miR-494 in PC-12 cells injury induced by lipopolysaccharide (LPS), as well as its mechanism.
The cell counting kit-8 (CKK-8) assay and apoptosis assay were respectively used to determine the proliferation and apoptosis of PC-12. The reverse transcription polymerase chain reaction (RT-PCR) analysis and western blot analysis displayed the expression of related factors at mRNA and protein level, respectively.
The results showed that LPS could significantly decrease cell viability, and promote the cell apoptosis and autophagy of PC-12 in a dose-dependent manner (p < 0.05). The overexpression of miR-494 could protect PC-12 cells from LPS-induced injury, as miR-494 overexpression increased cell viability, and reduced cell apoptosis and autophagy (p < 0.05). MiR-494 played a negative regulatory role in interleukin (IL)-13, and IL-13 was a direct target of miR-494. The overexpression of IL-13 could significantly aggravate LPS-diminished cell viability, and LPS-induced apoptosis and autophagy (p < 0.05). Besides, the overexpression of miR-494 did not attenuate LPS-induced injury when IL-13 was overexpressed. Furthermore, we found that the overexpression of miR-494 could significantly promote the phosphorylation of STAT6/MAPK and ERK/JNK signaling pathway.
MiR-494 could protect PC-12 cells from LPS-induced cell damage by targeting IL-13, and the activation of STAT6/MAPK and ERK/JNK pathways.
有报道称 miR-494 作为一种肿瘤抑制因子，能够抑制某些癌细胞的增殖和集落形成。然而，直到目前为止，miR-494 在脊髓损伤（SCI）中的作用仍未有报道。
本研究旨在探讨 miR-494 在脂多糖（LPS）诱导的 PC-12 细胞损伤中的表达情况及其作用机制。
采用细胞计数试剂盒-8（CCK-8）检测和凋亡检测分别检测 PC-12 细胞的增殖和凋亡情况。逆转录聚合酶链反应（RT-PCR）分析和蛋白质印迹分析分别检测相关因子在 mRNA 和蛋白水平上的表达情况。
结果表明，LPS 可显著降低 PC-12 细胞活力，并呈剂量依赖性促进 PC-12 细胞凋亡和自噬（p < 0.05）。miR-494 的过表达可保护 PC-12 细胞免受 LPS 诱导的损伤，因为 miR-494 的过表达可增加细胞活力，并减少细胞凋亡和自噬（p < 0.05）。miR-494 对白细胞介素（IL）-13 发挥负调控作用，而 IL-13 是 miR-494 的直接靶标。IL-13 的过表达可显著加重 LPS 降低的细胞活力，并加重 LPS 诱导的凋亡和自噬（p < 0.05）。此外，当 IL-13 过表达时，miR-494 的过表达并不能减轻 LPS 诱导的损伤。此外，我们发现 miR-494 的过表达可显著促进 STAT6/MAPK 和 ERK/JNK 信号通路的磷酸化。
miR-494 通过靶向 IL-13 并激活 STAT6/MAPK 和 ERK/JNK 信号通路，可保护 PC-12 细胞免受 LPS 诱导的细胞损伤。
