Glutamate excitotoxicity has been shown to play an important role in glaucoma, and glutamate can induce ferroptosis. The p38 mitogenactivated protein kinase(MAPK) pathway inhibitor SB202190 has a potential ability to ...Glutamate excitotoxicity has been shown to play an important role in glaucoma, and glutamate can induce ferroptosis. The p38 mitogenactivated protein kinase(MAPK) pathway inhibitor SB202190 has a potential ability to suppress ferroptosis, and its downstream targets, such as p53, have been shown to be associated with ferroptosis. However, whether ferroptosis also occurs in retinal ganglion cells in response to glutamate excitotoxicity and whether inhibition of ferroptosis reduces the loss of retinal ganglion cells induced by glutamate excitotoxicity remain unclear. This study investigated ferroptosis in a glutamate-induced glaucoma rat model and explored the effects and molecular mechanisms of SB202190 on retinal ganglion cells. A glutamate-induced excitotoxicity model in R28 cells and an N-methyl-D-aspartate-induced glaucoma model in rats were used. In vitro experiments showed that glutamate induced the accumulation of iron and lipid peroxide and morphological changes of mitochondria in R28 cells, and SB202190 inhibited these changes. Glutamate induced the levels of p-p38 MAPK/p38 MAPK and SAT1 and decreased the expression levels of ferritin light chain, SLC7A11, and GPX4. SB202190 inhibited the expression of iron death-related proteins induced by glutamate. In vivo experiments showed that SB202190 attenuated N-methyl-D-aspartate-induced damage to rat retinal ganglion cells and improved visual function. These results suggest that SB202190 can inhibit ferroptosis and protect retinal ganglion cells by regulating ferritin light chain, SAT1, and SLC7A11/Gpx4 pathways and may represent a potential retina protectant.展开更多
Objective: To study the role of p38MAPK in mediating TNF-α-induced apoptosis of rat glioma cell line C6. Methods: Effect of TNF-α on the proliferation of C6 cells was determined by MTT assay. The TNF-α induced apop...Objective: To study the role of p38MAPK in mediating TNF-α-induced apoptosis of rat glioma cell line C6. Methods: Effect of TNF-α on the proliferation of C6 cells was determined by MTT assay. The TNF-α induced apoptosis was detected by transmission electron microscopy and flow cytometry. The expression of p38MAPK was detected by SABC method and Western-blot. The effect of SB202190, a specific inhibitor of p38MAPK, on TNF-α-induced apoptosis was observed by flow cytometry and SABC method. Results: Inhibitory rate of TNF-α(2×105 U/L) on C6 cells was 43.75%. In the TNF-α treated group, apoptotic cells were observed by transmission electron microscopy and the apoptotic rate was 37.5% by flow cytometry. p38MAPK positive signals were detected by SABC method and Western-blot. In the SB202190 treated group, the apoptotic rate was 7.0% and no p38MAPK signals were found. Conclusion: Apoptosis of C6 cells and expression of p38MAPK can be induced by TNF-α. The activation of p38MAPK promotes the apoptosis of C6 cells.展开更多
基金supported by the National Natural Science Foundation of China,Nos.81974132,81770927Hunan Provincial Health Commission,No.20220702839+1 种基金the Natural Science Foundation of Hunan Province of China,No.2022JJ30076National Key R&D Program of China,No.2021YFA1101202(all to WS)。
文摘Glutamate excitotoxicity has been shown to play an important role in glaucoma, and glutamate can induce ferroptosis. The p38 mitogenactivated protein kinase(MAPK) pathway inhibitor SB202190 has a potential ability to suppress ferroptosis, and its downstream targets, such as p53, have been shown to be associated with ferroptosis. However, whether ferroptosis also occurs in retinal ganglion cells in response to glutamate excitotoxicity and whether inhibition of ferroptosis reduces the loss of retinal ganglion cells induced by glutamate excitotoxicity remain unclear. This study investigated ferroptosis in a glutamate-induced glaucoma rat model and explored the effects and molecular mechanisms of SB202190 on retinal ganglion cells. A glutamate-induced excitotoxicity model in R28 cells and an N-methyl-D-aspartate-induced glaucoma model in rats were used. In vitro experiments showed that glutamate induced the accumulation of iron and lipid peroxide and morphological changes of mitochondria in R28 cells, and SB202190 inhibited these changes. Glutamate induced the levels of p-p38 MAPK/p38 MAPK and SAT1 and decreased the expression levels of ferritin light chain, SLC7A11, and GPX4. SB202190 inhibited the expression of iron death-related proteins induced by glutamate. In vivo experiments showed that SB202190 attenuated N-methyl-D-aspartate-induced damage to rat retinal ganglion cells and improved visual function. These results suggest that SB202190 can inhibit ferroptosis and protect retinal ganglion cells by regulating ferritin light chain, SAT1, and SLC7A11/Gpx4 pathways and may represent a potential retina protectant.
文摘Objective: To study the role of p38MAPK in mediating TNF-α-induced apoptosis of rat glioma cell line C6. Methods: Effect of TNF-α on the proliferation of C6 cells was determined by MTT assay. The TNF-α induced apoptosis was detected by transmission electron microscopy and flow cytometry. The expression of p38MAPK was detected by SABC method and Western-blot. The effect of SB202190, a specific inhibitor of p38MAPK, on TNF-α-induced apoptosis was observed by flow cytometry and SABC method. Results: Inhibitory rate of TNF-α(2×105 U/L) on C6 cells was 43.75%. In the TNF-α treated group, apoptotic cells were observed by transmission electron microscopy and the apoptotic rate was 37.5% by flow cytometry. p38MAPK positive signals were detected by SABC method and Western-blot. In the SB202190 treated group, the apoptotic rate was 7.0% and no p38MAPK signals were found. Conclusion: Apoptosis of C6 cells and expression of p38MAPK can be induced by TNF-α. The activation of p38MAPK promotes the apoptosis of C6 cells.