孕酮减轻ATP诱导的SH-SY5Y细胞损伤

目的:探讨孕酮对抗腺苷三磷酸(ATP)诱导的人神经母细胞瘤SH-SY5Y细胞损伤的神经保护作用和机制。方法:取对数生长期的SH-SY5Y细胞按照孕酮或ATP浓度的不同进行分组,CCK-8法检测细胞存活率,YO-PRO-1染色检测细胞膜通透性,Fluo-3染色检测细胞内Ca~(2+)浓度的变化,Western blot法检测嘌呤能P2X_7受体表达的变化。结果:与对照组相比,不同浓度(1、3、5和7 mmol/L)ATP作用2 h,SH-SY5Y细胞存活率显著降低(P0.05),细胞摄入YO-PRO-1的荧光强度明显增加(P0.05),且呈剂量依赖性。浓度为3、10和30 nmol/L的孕酮预孵育30 min可减轻ATP损伤作用,细胞存活率较单纯ATP组明显升高(P0.05或P0.01)。孕酮(30nmol/L)或P2X_7受体拮抗剂KN-62(500 nmol/L)预孵育30 min均可显著抑制ATP诱导的胞内YO-PRO-1的荧光增强(P0.01),而孕酮和KN-62两者之间没有明显差异。正常组细胞内钙离子含量少,ATP组细胞内钙离子荧光强度较对照组明显增高(P0.05),孕酮(30 nmol/L)或KN-62(500 nmol/L)预孵育30 min可明显降低(P0.05)ATP诱导的胞内钙荧光增强,而孕酮和KN-62两者之间的作用无明显差异。ATP组SH-SY5Y细胞P2X_7受体表达较对照组明显增加(P0.05),而孕酮(30 nmol/L)预孵育30 min则可显著降低ATP诱导的P2X_7受体表达(P0.05)。结论:孕酮可抑制ATP诱导的P2X_7受体表达、膜孔形成和胞内Ca~(2+)升高,降低细胞死亡率,明显减轻高浓度ATP对SH-SY5Y细胞的损伤作用。

Effect of progesterone on SH-SY5Y cells injured by ATP

AIM: To investigate the neuroprotective effect of progesterone against adenosine triphosphate (ATP)-injured human neuroblastoma SH-SY5Y cells.METHODS: The SH-SY5Y cells in the logarithmic phase were divided into different groups according to the progesterone and ATP concentrations. The cell viability was measured by CCK-8 assay. The membrane permeability was detected using fluorescent dye YO-PRO-1. Cytosolic Ca²⁺ concentration was measured with fluorescent dye Fluo-3/AM. The expression of purinergic P2X₇ receptor was assessed by Western blot.RESULTS: The viability of the SH-SY5Y cells was significantly decreased (P<0.05) and YO-PRO-1 uptake was obviously increased (P<0.05) in a concentration-dependent manner compared with control group when SH-SY5Y cells were treated with ATP at 1, 3, 5 and 7 mmol/L for 2 h. The viability reduction of the SH-SY5Y cells induced by ATP was obviously counteracted by treatment with progesterone at 3, 10 and 30 nmol/L for 30 min (P<0.05) as compared with ATP group. YO-PRO-1 fluorescence enhancement induced by ATP in SH-SY5Y cells was significantly reduced (P<0.05) by progesterone (30 nmol/L) or P2X₇ receptor antagonist KN-62 (500 nmol/L) pretreatment for 30 min, and no obvious difference between treatments with progesterone and KN-62 was observed. Cytosolic Ca²⁺ fluorescence intensity in normal group was a little, but that in ATP group was increased (P<0.05). Progesterone or KN-62 pretreatment significantly decreased the cytosolic fluorescence intensity of Ca²⁺ induced by ATP (P<0.05). However, no obvious difference between treatments with progesterone and KN-62 was found. The expression of P2X₇ receptor in ATP group was significantly higher than that in control group (P<0.05), and progesterone inhibited ATP-induced P2X₇ receptor expression (P<0.05).CONCLUSION: Progesterone inhibits P2X₇ receptor expression, membrane pore formation, intracellular Ca²⁺ increase and cell death induced by ATP, so progesterone may protect SH-SY5Y cells against ATP-induced injuries.