Effect of small nucleolar RNA host gene 5 on hypoxia/reoxygenation injury of astrocytes / 中华行为医学与脑科学杂志

ABSTRACT

Objective:To explore the effect of lncRNA SNHG5 on injury of astrocytes induced by hypoxia/reoxygenation (H/R).Methods:(1) Astrocytes were cultured in vitro. The H/R cell model was established by hypoxia culture for 6 hours and then reoxygenaion culture for 18 hours. Lipofectamine? 2000 liposome method was used to transfect lncRNA SNHG5 into astrocytes. RT-qPCR was used to detect the expression of lncRNA SNHG5 in H/R cells and after transfection. (2) Astrocytes were divided into normal control group, model group, transfection control group (pcDNA-NC was transfected first, then H/R cell model was established) and transfection group (pcDNA-lncRNA SNHG5 was transfected first, then H/R cell model was established). Then the effect of overexpression of lncRNA SNHG5 on astrocytes was observed. (3)The astrocytes transfected with lncRNA SNHG5 and H/R intervention were divided into transfection+ vehicle group (0.1% DMSO incubation) and transfection+ inhibitor group (20 μmol/L LY294002 incubation), and then observe the effect of the inhibitor of PI3K/Akt signaling pathway LY294002 on H/R astrocytes was observed. (4) CCK-8 was used to detect cell proliferation. Flow cytometry was used to detect cell apoptosis. Western blot was used to detect the expression of cell proliferation proteins (Cyclin D1 and Cyclin E), apoptotic proteins (Caspase-3 and Bax), p-PI3K and p-AKT protein. ELISA was used to detect the levels of IL-1β and TNF-α. The colorimetric method was used to detect the level of lactate dehydrogenase(LDH) in cell culture supernatants and the level of malondialdehyde(MDA) and superoxide dismutase(SOD) in cells. SPSS 22.0 software was used for independent sample t-test and one-way ANOVA, and LSD- t test was used for further pairwise comparisons. Results:(1) RT-qPCR results showed that the level of lncRNA SNHG5 in astrocytes induced by H/R was lower than that in the normal cultured cells ( t=33.28, P<0.05). (2) lncRNA SNHG5 overexpression experiment The cell proliferation activity of the model group was lower than that in the normal control group (CCK-8 OD value (0.64±0.02), (1.23±0.02), t=62.58, P<0.05). The levels of proliferation proteins Cyclin D1 and Cyclin E in the model group were lower than those of the normal control group ( t=33.54, 32.20, both P<0.05). The cell proliferation activity of the transfection group was higher than that of the transfection control group (CCK-8 OD value (1.49±0.02), (0.65±0.03), t=69.89, P<0.05), the levels of cell proliferation proteins Cyclin D1 and Cyclin E in the transfection group were lower than those in the transfection control group ( t=24.96, 28.46, both P<0.05). The apoptosis rate of the model group was higher than that of the control group (flow cytometry results: (25.33±1.13)%, (9.06±0.21)%, t=42.47, P<0.05), and the levels of apoptotic proteins Caspase-3 and Bax were also higher than those of the control group ( t=57.41, 41.60, both P<0.05). The Caspase-3 rate of the transfection group was lower than that of the transfection control group((16.56±0.60)%, (25.89±1.18)%, t=21.14, P<0.05), and the levels of apoptotic proteins Caspase-3 and Bax were also higher than those of the transfection control group( t=77.79, 58.34, both P<0.05). The levels of p-PI3K and p-AKT proteins in the model group were lower than those in the control group ( t=56.35, 33.94, both P<0.05), and the levels of p-PI3K and p-AKT proteins in the transfection group were higher than those in the transfection control group ( t=130.14, 76.37, both P<0.05). The results of ELISA showed that the levels of IL-1β and TNF-α in the model group were higher than those in the control group ( t=58.04, 30.63, both P<0.05), but the levels of IL-1β and TNF-α in the transfection group were lower than those in the transfection control group ( t=33.63, 39.01, both P<0.05). The colorimetric method showed that the levels of LDH and MDA in the model group were higher than those in the control group ( t=65.51, 41.85, both P<0.05), but the level of SOD was lower than that in the control group ( t=48.82, P<0.05). The levels of LDH and MDA in the transfection group were lower than those in the transfection control group ( t=37.93, 30.72, both P<0.05), but the level of SOD was higher than that in the transfection control group ( t=30.32, P<0.05). (3) PI3K/Akt signaling pathway inhibition experiment the cell proliferation activity of the transfection+ inhibitor group was lower than that of the transfection+ vehicle group (CCK-8 OD value (0.97±0.02), (1.46±0.03), t=15.24, P<0.05), and the related proliferation proteins Cyclin D1 and Cyclin E were also lower ( t=11.41, 13.15, both P<0.05). The apoptosis rate of the transfection+ inhibitor group was higher than that of the transfection+ vehicle group (Flow cytometry (26.11±0.86)%, (16.06±0.44)%, t=10.45, P<0.05). The apoptosis rate of the transfection+ inhibitor group was higher than that of the transfection+ vehicle group (Flow cytometry (26.11±0.86)%, (16.06±0.44)%, t=10.45, P<0.05), and the related apoptosis protein Caspase-3 and Bax were also higher ( t=19.06, 13.54, both P<0.05). The expression levels of p-PI3K and p-AKT protein in the transfection+ inhibitor group were lower than those in the transfection+ vehicle group ( t=36.67, 27.34, both P<0.05). ELISA results showed that the levels of IL-1β and TNF-α in the transfection+ inhibitor group were higher than those in the transfection+ vehicle group ( t=15.17, 9.44, both P<0.05). The colorimetric method results showed that the levels of LDH and MDA in the transfection+ inhibitor group were the same as those in the transfection+ vehicle group ( t=15.33, 9.05, both P<0.05), but the level of SOD was lower than the transfection+ vehicle group ( t=11.04, P<0.05). Conclusion:Overexpression of lncRNA SNHG5 may promote the proliferation of astrocytes induced by hypoxia/reoxygenation, and inhibit cell apoptosis, inflammation and oxidative stress.