Frontiers in Pharmacology (Sep 2024)

Silibinin inhibits PM2.5-induced liver triglyceride accumulation through enhancing the function of mitochondrial Complexes I and II

  • Dexin Li,
  • Dexin Li,
  • Dexin Li,
  • Dexin Li,
  • Dexin Li,
  • Jingxin Zhang,
  • Jingxin Zhang,
  • Jingxin Zhang,
  • Jingxin Zhang,
  • Jingxin Zhang,
  • Yuxin Jin,
  • Yuxin Jin,
  • Yuxin Jin,
  • Yuxin Jin,
  • Yuxin Jin,
  • Yaoxuan Zhu,
  • Yaoxuan Zhu,
  • Yaoxuan Zhu,
  • Yaoxuan Zhu,
  • Yaoxuan Zhu,
  • Xiaoqing Lu,
  • Xiaoqing Lu,
  • Xiaoqing Lu,
  • Xiaoqing Lu,
  • Xiaoqing Lu,
  • Xinmei Huo,
  • Xinmei Huo,
  • Xinmei Huo,
  • Xinmei Huo,
  • Xinmei Huo,
  • Chunshui Pan,
  • Chunshui Pan,
  • Chunshui Pan,
  • Chunshui Pan,
  • Lijun Zhong,
  • Kai Sun,
  • Kai Sun,
  • Kai Sun,
  • Kai Sun,
  • Li Yan,
  • Li Yan,
  • Li Yan,
  • Li Yan,
  • Lulu Yan,
  • Lulu Yan,
  • Lulu Yan,
  • Lulu Yan,
  • Ping Huang,
  • Ping Huang,
  • Ping Huang,
  • Ping Huang,
  • Quan Li,
  • Quan Li,
  • Quan Li,
  • Quan Li,
  • Jing-Yan Han,
  • Jing-Yan Han,
  • Jing-Yan Han,
  • Jing-Yan Han,
  • Jing-Yan Han,
  • Yin Li,
  • Yin Li,
  • Yin Li,
  • Yin Li,
  • Yin Li

DOI
https://doi.org/10.3389/fphar.2024.1435230
Journal volume & issue
Vol. 15

Abstract

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BackgroundThe standardized extract of milk thistle seeds, known as silibinin, has been utilized in herbal medicine for over two centuries, with the aim of safeguarding the liver against the deleterious effects of various toxic substances. However, the role of silibinin in Particulate Matter (PM2.5)-induced intrahepatic triglyceride accumulation remains unclear. This study seeks to investigate the impact of silibinin on PM2.5-induced intrahepatic triglyceride accumulation and elucidate potential underlying mechanisms.MethodsA model of intrahepatic triglyceride accumulation was established in male C57BL/6J mice through intratracheal instillation of PM2.5, followed by assessment of liver weight, body weight, liver index, and measurements of intrahepatic triglycerides and cholesterol after treatment with silibinin capsules. Hep G2 cells were exposed to PM2.5 suspension to create an intracellular triglyceride accumulation model, and after treatment with silibinin, cell viability, intracellular triglycerides and cholesterol, fluorescence staining for Nile Red (lipid droplets), and DCFH-DA (Reactive Oxygen Species, ROS), as well as proteomics, real-time PCR, and mitochondrial function assays, were performed to investigate the mechanisms involved in reducing triglycerides.ResultsPM2.5 exposure leads to triglyceride accumulation, increased ROS production, elevated expression of inflammatory factors, decreased expression of antioxidant factors, and increased expression of downstream genes of aryl hydrocarbon receptor. Silibinin can partially or fully reverse these factors, thereby protecting cells and animal livers from PM2.5-induced damage. In vitro studies show that silibinin exerts its protective effects by preserving oxidative phosphorylation of mitochondrial complexes I and II, particularly significantly enhancing the function of mitochondrial complex II. Succinate dehydrogenase (mitochondrial complex II) is a direct target of silibinin, but silibinin A and B exhibit different affinities for different subunits of complex II.ConclusionSilibinin improved the accumulation of intrahepatic triglycerides induced by PM2.5, and this was, at least in part, explained by an enhancement of oxidative phosphorylation in mitochondrial Complexes I and II.

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