Periplocin and bufalin induce cardiotoxicity by regulating AMPK/SIRT1/PGC-1α pathway to inhibit energy metabolism and trigger autophagy
Xinyue Gao, Jian Zhang, Yifan Lin, Kun Tian, Jionghong Tu, Zekai Wu, Xiaoqi Lv, Hong Hu, Xuyang Liu, Shiyu Lin, An Zhu
Abstract
OBJECTIVE: Periplocin (PE) and bufalin (BU)-active ingredients of traditional Chinese medicine-exhibit diverse biological activities, including cardiotonic and antitumor effects. However, their clinical application is limited by dose-dependent cardiotoxicity, the specific mechanisms of which remain unclear. METHODS: The cardiotoxicity of PE and BU was evaluated using cardiomyoblasts and zebrafish as models. Epitranscriptomics, computational simulation techniques, and cellular thermal shift assays (CETSA) were employed for target prediction. Fluorescent probes, biochemical assays, quantitative real-time polymerase chain reaction (RT-qPCR), and western blotting were used to detect indicators related to mitochondrial function, energy metabolism, and autophagy. Functional validation was conducted via gene knockdown and pharmacological rescue experiments. RESULTS: Exposure to PE or BU caused cardiotoxicity, characterized by energy metabolism dysfunction, mitochondrial damage, and excessive autophagy. Epitranscriptomic analysis revealed dysregulated expression of genes related to these processes because of altered N6-methyladenosine (m6A) modification. Mechanistically, knockdown of the m6A reader YTH domain-containing protein 1 (YTHDC1) or of the eraser alkB homolog 5 (ALKBH5) attenuated mitochondrial dysfunction and autophagic activation. Furthermore, cytotoxicity was alleviated by AMP-activated protein kinase (AMPK) activator A-769662 and autophagy inhibitor 3-methyladenine (3-MA). CONCLUSION: PE and BU impair mitochondrial function and energy metabolism via the m6A-modified AMPK/sirtuin 1 (SIRT1)/peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) axis, leading to excessive autophagy and cardiotoxicity. These findings reveal potential therapeutic targets for alleviating the cardiotoxicity of PE and BU.