Opening of ATP-sensitive K+channels protects H9c2 cardiac cells against high glucose-induced injury and inflammation by inhibiting TLR4/NF-κB pathway
10.3969/j.issn.1000-4718.2016.07.001
- VernacularTitle:ATP敏感性钾通道的开放通过抑制TLR4／NF－κB通路对抗高糖引起的H9c2心肌细胞损伤和炎症
- Author:
Weijie LIANG
;
Meiji CHEN
;
Jieyi HE
;
Huimin HUANG
;
Shenglong YU
;
Jun CHEN
;
Jingfu CHEN
;
Mingcai SONG
;
Xinxue LIAO
- Publication Type:Journal Article
- Keywords:
ATP-sensitive K+channels;
Toll-like receptor 4;
Nuclear factor-κB;
High glucose;
Cardiomyo-cytes;
Injury;
Inflammation
- From:
Chinese Journal of Pathophysiology
2016;32(7):1153-1160
- CountryChina
- Language:Chinese
-
Abstract:
AIM:To investigate whether the opening of ATP-sensitive K+(KATP) channels protects H9c2 car-diac cells against high glucose ( HG)-induced injury and inflammation by inhibiting the Toll-like receptor 4 ( TLR4 )/nu-clear factor-κB ( NF-κB) pathway.METHODS:The protein levels of TLR4 and NF-κB p65 were determined by Western blot.The levels of interleukin-1β(IL-1β) and tumor necrosis factor-α(TNF-α) were detected by ELISA.The cell viabil-ity was measured by CCK-8 assay.Mitochondrial membrane potential (MMP) was examined by rhodamine 123 (Rh 123) staining followed by photofluorography.The intracellular levels of reactive oxygen species ( ROS) were detected by 2′, 7′-
dichlorfluorescein-diacetate (DCFH-DA) staining followed by photofluorography.The number of apoptotic cells was ob-served by Hoechst 33258 nuclear staining followed by photofluorography.RESULTS: After the H9c2 cardiac cells were treated with HG (35 mmol/L glucose) for 24 h, the protein levels of TLR4 and phosphorylated NF-κB p65 ( p-NF-κB p65) were significantly increased.Pretreatment of the cells with 100 μmol/L diazoxide ( DZ, a KATP channel opener) for 30 min before exposure to HG considerably blocked the up-regulation of the TLR4 and p-NF-κB protein levels induced by HG.Moreover, co-treatment of the cells with 30 μmol/L TAK-242 (an inhibitor of TLR4) obviously inhibited the HG-in-duced up-regulation of the p-NF-κB p65 protein level.On the other hand, pretreatment of the cells with 100 μmol/L DZ had a clear myocardial protection effect, which attenuated the HG-induced cytotoxicity, inflammatory response, mitochon-drial damage, oxidative stress and apoptosis, evidenced by an increase in the cell viability, and decreases in the levels of IL-1βand TNF-α, MMP loss, ROS generation and the number of apoptotic cells.Similarly, co-treatment of H9c2 cardiac cells with 30μmol/L TAK-242 or 100μmol/L PDTC ( an inhibitor of NF-κB) and HG for 24 h also obviously reduced the above injuries and inflammation induced by HG.CONCLUSION: The opening of KATP channels protects H9c2 cardiac cells against HG-induced injury and inflammation by inhibiting the TLR4/NF-κB pathway.
