Effects and mechanisms of ATP-sensitive potassium channel openers on microglial inflammatory response induced by oxygen-glucose deprivation/reoxygenation
10.3760/cma.j.cn371468-20240127-00054
- VernacularTitle:ATP敏感性钾通道开放剂对氧糖剥夺/复氧小胶质细胞炎性反应的影响及其机制
- Author:
Shanshan YIN
1
;
Chenming ZHAO
;
Qiujun ZHANG
;
Yuanzheng ZHAO
Author Information
1. 郑州大学第五附属医院神经内科,郑州 450052
- Keywords:
ATP-sensitive potassium channel;
Nicorandil;
Oxygen-glucose deprivation;
Pyroptosis;
AIM2 inflammasome;
NF-κB signal pathway
- From:
Chinese Journal of Behavioral Medicine and Brain Science
2024;33(9):776-782
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the effects and mechanisms of Nicorandil, an ATP-sensitive potassium channel (KATP) opener, on pyroptosis and inflammatory responses in microglia(BV2) induced by oxygen-glucose deprivation/reoxygenation (OGD/R).Methods:BV2 cells were divided into control group, OGD/R group, and OGD/R+ Nicorandil group.And the cells were subjected to oxygen-glucose deprivation for 3 hours and then reoxygenated for 24 hours to establish an OGD/R cell model. OGD/R+ Nicorandil group cells were incubated with 5 μg/mL Nicorandil culture medium for 24 hours after oxygen-glucose deprivation for 3 hours.The cell proliferation activity was detected by CCK8 assay.Calcein/propidium iodide (calcein/PI) assay kit was used to detect the membrane porosity rupture rate of cell in each group.Western blot analysis was performed to detect the protein expression levels of nuclear factor-κB (NF-κB), phosphorylated NF-κB (p-NF-κB), inhibitor of nuclear factor-κB α(IκB-α), phosphorylated IκB-α (p-IκB-α), absent in melanoma 2 (AIM2), cleaved-caspase-1, gasdermin D-N (GSDMD-N), interleukin-18 (IL-18), and interleukin-1β (IL-1β). Immunofluorescence was used to detect the protein expression levels of AIM2 and GSDMD-N in each group. Statistical analysis was performed by SPSS 26.0 software. One-way ANOVA was used for multiple group comparisons, and LSD test was used for pairwise comparisons.Results:(1) There were statistically significant differences in the membrane porosity rupture rates among the three groups ( F=615.882, P<0.05). The membrane porosity rupture rate in the Nicorandil group was lower than that in the OGD/R group ((41.50±3.04)%, (59.44±3.66)%, P<0.05). (2) Western blot results showed that the protein expression levels of p-NF-κB, NF-κB, p-IκB-α, and IκB-α were significantly different among the three groups ( F=10.000, 62.652, 67.121, 101.023, all P<0.05). The levels of p-NF-κB, NF-κB and p-IκB-α in the OGD/R+ Nicorandil group ((0.60±0.13), (0.87±0.06), (0.55±0.06), respectively) were lower than those in the OGD/R group ((1.02±0.09), (1.03±0.09), (0.86±0.04), respectively) (all P<0.05). The level of IκB-α in the OGD/R+ Nicorandil group ((0.63±0.05), (0.46±0.06)) was higher than that in the OGD/R group( P<0.05). (3) The protein expression levels of AIM2, cleaved-caspase-1, GSDMD-N, IL-18, and IL-1β were significantly different among the three groups ( F=65.926, 12.428, 66.447, 44.831, 52.960, all P<0.05). The levels of AIM2, cleaved-caspase-1, GSDMD-N, IL-18 and IL-1β in the OGD/R+ Nicorandil group ((0.78±0.04), (0.71±0.09), (0.54±0.04), (0.72±0.07), (0.50±0.08), respectively) were lower than those in the OGD/R group ((0.94±0.09), (0.89±0.09), (0.85±0.04), (0.90±0.07), (0.99±0.03), respectively) (all P<0.05). (4) Immunofluorescence results showed statistically significant differences in the fluorescence intensity of pyroptosis marker proteins AIM2 and GSDMD-N among the three groups ( F=36.353, 46.817, both P<0.05). The fluorescence intensities of AIM2 ((124.36±7.91), (140.19±5.63)) and GSDMD-N ((134.16±5.18), (147.45±5.63))in the OGD/R+ Nicorandil group were lower than those in the OGD/R group (both P<0.05). Conclusion:Nicorandil can mitigate BV2 cell damage following oxygen-glucose deprivation, inhibiting the release of pro-inflammatory factors. The mechanism may be related to the downregulation of the expression of NF-κB related proteins and inhibition of AIM2 inflammasome-mediated pyroptosis after OGD/R.