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MiR-221/SIRT1/Nrf2 signal axis regulates high glucose induced apoptosis in human retinal microvascular endothelial
1Department of Ophthalmology, Renmin Hospital of Wuhan University, No. 238, Jiefang Road, Wuhan, 430060, Hubei Province, P. R. China.
Background:
Diabetic retinopathy (DR) is a serious symptom associated with diabetes and could cause much suffer to patients. MiR-221, SIRT1 and Nrf2 were associated with apoptosis and proliferation and their expression were altered in DR patients. However, their roles and regulatory mechanisms in human retinal microvascular endothelial cells (hRMEC) were not clear.
Methods:
Expression of mRNA was detected by qRT-PCR. Protein expression was detected by Western blot. Interaction between miR-221 and SIRT1 was predicted by bioinformatics analysis and validated by dual-luciferase reporter assay. We analyzed the viability and apoptosis of hRMEC by MTT assay and FACS assay, respectively.
Results:
High glucose (HG) treatment enhanced expression of miR-221 and inhibited expression of SIRT1 and Nrf2. MiR-221 overexpression promoted apoptosis under HG condition. Moreover, miR-221 directly interacted with mRNA of SIRT1 and inhibited SIRT1 expression in hRMEC, through which miR-221 inhibited Nrf2 pathway and induced apoptosis of hRMEC.
Conclusion:
Our data demonstrated that miR-221/SIRT1/Nrf2 signal axis could promote apoptosis in hRMEC under HG conditions. This finding could provide theoretical support for future studies and may contribute to development of new treatment options to retard the process of DR development.
Insights
MicroRNA-221 promotes diabetic retinopathy (DR) by increasing apoptosis in retinal cells. It targets SIRT1, inhibiting the Nrf2 pathway, offering potential therapeutic targets for DR.
Area of Science:
- Ophthalmology
- Molecular Biology
- Cell Biology
Background:
- Diabetic retinopathy (DR) is a diabetes complication impacting vision.
- MiR-221, SIRT1, and Nrf2 are implicated in cell apoptosis and proliferation, with altered expression in DR.
- The precise roles of these molecules in human retinal microvascular endothelial cells (hRMEC) were unclear.
Purpose of the Study:
- To investigate the roles and regulatory mechanisms of miR-221, SIRT1, and Nrf2 in hRMEC under high glucose conditions.
- To elucidate the signaling pathway involving miR-221, SIRT1, and Nrf2 in DR pathogenesis.
Main Methods:
- Gene expression analyzed via qRT-PCR and Western blot.
- MiR-221 and SIRT1 interaction validated using bioinformatics and dual-luciferase reporter assays.
- Cell viability and apoptosis assessed using MTT and FACS assays.
Main Results:
- High glucose increased miR-221 expression while decreasing SIRT1 and Nrf2.
- Overexpression of miR-221 enhanced apoptosis in hRMEC under high glucose.
- MiR-221 directly targets SIRT1 mRNA, inhibiting SIRT1 expression and consequently suppressing the Nrf2 pathway, leading to hRMEC apoptosis.
Conclusions:
- The miR-221/SIRT1/Nrf2 axis promotes apoptosis in hRMEC under high glucose.
- This pathway provides a potential therapeutic target for mitigating diabetic retinopathy progression.
