Resveratrol shields against cisplatin-induced ototoxicity through epigenetic lncRNA GAS5 modulation of miR-455-5p/PTEN pathway

• Published in: International immunopharmacology 2024-09, Vol.138, p.112464, Article 112464
• Main Authors: Wu, Wenjin, Li, Yingru, He, Jingchun, Yang, Jun, Liu, Yupeng
• Format: Article
• Language: English
• Subjects: Animals; Apoptosis - drug effects; Cell Line; Cisplatin; DDP ototoxicity; DNA (Cytosine-5-)-Methyltransferase 1 - genetics; DNA (Cytosine-5-)-Methyltransferase 1 - metabolism; DNMT1; Epigenesis, Genetic - drug effects; lncRNA GAS5; Male; Mice; Mice, Inbred C57BL; MicroRNAs - genetics; MicroRNAs - metabolism; miR-455-5p; Ototoxicity - prevention & control; PTEN Phosphohydrolase - genetics; PTEN Phosphohydrolase - metabolism; Resveratrol; Resveratrol - pharmacology; Resveratrol - therapeutic use; RNA, Long Noncoding - genetics; RNA, Long Noncoding - metabolism; Signal Transduction - drug effects
• ISSN: 1567-5769; 1878-1705; 1878-1705
• DOI: 10.1016/j.intimp.2024.112464

•Innovative Mechanism Unveiled: Our study reveals that GAS5 functions as a molecular sponge for miR-455-5p, thereby regulating PTEN expression.•Epigenetic Modulation by Resveratrol: We discovered that resveratrol upregulates DNMT1, which in turn downregulates the GAS5-mediated miR-455-5p/PTEN axis.•GAS5 Effects: GAS5 counteracts resveratrol’s effectiveness in reducing apoptosis and ROS by downregulating miR-455-5p.•Role of DNMT1 in Cellular Defense: DNMT1 enhances resveratrol’s defense against DDP-triggered apoptosis and ROS in HEI-OCI cells via GAS5 methylation.•In Vivo Protective Effects: DNMT1 also amplifies resveratrol’s protective impact against DDP-induced ototoxicity in vivo through GAS5 methylation. Our previous research demonstrated that resveratrol counters DDP-induced ototoxicity by upregulating miR-455-5p, which targets PTEN. This study aimed to elucidate the underlying mechanisms involving GAS5 and DNA methyltransferase 1 (DNMT1) in resveratrol’s protective action. A luciferase reporter assay and RNA immunoprecipitation (RIP) assay were employed to study the binding between GAS5 and miR-455-5p, as well as between miR-455-5p and PTEN. HEI-OC1 cells treated with DDP were transfected with vectors for GAS5, si-GAS5, DNMT1, si-DNMT1, and miR-455-5p mimics, as well as PTEN. Subsequently, they were treated with resveratrol and exposed to DDP, both separately and in combination. The distribution of CpG islands in the GAS5 promoter was identified using MethyPrimer, and methylation-specific PCR (MSP) was conducted to determine the methylation levels of GAS5. Chromatin immunoprecipitation (ChIP) was utilized to examine the interaction between DNMT1 and GAS5. The viability of HEI-OC1 cells, catalase (CAT) activity, apoptosis, and ROS levels were assessed using the CCK-8 assay, CAT assay, TUNEL staining, and flow cytometry, respectively. An in vivo mouse model was developed to measure auditory brainstem response (ABR) thresholds, while RT-qPCR and Western blot analysis were employed to evaluate molecular levels. Our study discovered that GAS5 acts as a sponge for miR-455-5p, thereby increasing PTEN expression in DDP-treated HEI-OC1 cells. This process was reversed upon treatment with resveratrol. Importantly, DNMT1 promoted the methylation of the GAS5 promoter, leading to the suppression of GAS5 expression. This suppression enhanced the effectiveness of resveratrol in combating DDP-induced apoptosis and ROS in HEI-OC1 cells and amplified its protective eff