2. Academic Validation
  3. Hepatic deficiency of selenoprotein S exacerbates hepatic steatosis and insulin resistance

Hepatic deficiency of selenoprotein S exacerbates hepatic steatosis and insulin resistance

  • Cell Death Dis. 2022 Mar 28;13(3):275. doi: 10.1038/s41419-022-04716-w.
Lu Qiao  # 1 2,  Lili Men  # 1 2,  Shanshan Yu 1 2,  Junjie Yao 1 2,  Yu Li 1 2,  Mingming Wang 1 2,  Ying Yu 1 2,  Ning Wang 3 4,  Liyuan Ran 3 4,  Yingjie Wu 5 6 7,  Jianling Du 8 9
Affiliations

Affiliations

  • 1 Department of Endocrinology, the First Affiliated Hospital of Dalian Medical University, Dalian, China.
  • 2 Dalian Key Laboratory of Prevention and Treatment of Metabolic Diseases and the Vascular Complications, Dalian, China.
  • 3 Institute for Genome Engineered Animal Models of Human Diseases, Dalian Medical University, Dalian, China.
  • 4 National Center of Genetically Engineered Animal Models for International Research, Dalian Medical University, Dalian, China.
  • 5 Institute for Genome Engineered Animal Models of Human Diseases, Dalian Medical University, Dalian, China. yingjiewu@dmu.edu.cn.
  • 6 National Center of Genetically Engineered Animal Models for International Research, Dalian Medical University, Dalian, China. yingjiewu@dmu.edu.cn.
  • 7 Department of Molecular Pathobiology, New York University College of Dentistry, New York, NY, USA. yingjiewu@dmu.edu.cn.
  • 8 Department of Endocrinology, the First Affiliated Hospital of Dalian Medical University, Dalian, China. dujianlingcn@163.com.
  • 9 Dalian Key Laboratory of Prevention and Treatment of Metabolic Diseases and the Vascular Complications, Dalian, China. dujianlingcn@163.com.
  • # Contributed equally.
PMID: 35347118 DOI: 10.1038/s41419-022-04716-w
Abstract

Nonalcoholic fatty liver disease (NAFLD) is closely associated with Insulin resistance (IR) and type 2 diabetes mellitus (T2DM), which are all complex metabolic disorders. Selenoprotein S (SelS) is an endoplasmic reticulum (ER) resident selenoprotein involved in regulating ER stress and has been found to participate in the occurrence and development of IR and T2DM. However, the potential role and mechanism of SelS in NAFLD remains unclear. Here, we analyzed SelS expression in the liver of high-fat diet (HFD)-fed mice and obese T2DM model (db/db) mice and generated hepatocyte-specific SelS knockout (SelSH-KO) mice using the Cre-loxP system. We showed that hepatic SelS expression levels were significantly downregulated in HFD-fed mice and db/db mice. Hepatic SelS deficiency markedly increased ER stress markers in the liver and caused hepatic steatosis via increased fatty acid uptake and reduced fatty acid oxidation. Impaired Insulin signaling was detected in the liver of SelSH-KO mice with decreased phosphorylation levels of Insulin Receptor substrate 1 (IRS1) and protein kinase B (PKB/Akt), which ultimately led to disturbed glucose homeostasis. Meanwhile, our results showed hepatic protein kinase Cɛ (PKCɛ) activation participated in the negative regulation of Insulin signaling in SelSH-KO mice. Moreover, the inhibitory effect of SelS on hepatic steatosis and IR was confirmed by SelS overexpression in primary hepatocytes in vitro. Thus, we conclude that hepatic SelS plays a key role in regulating hepatic lipid accumulation and Insulin action, suggesting that SelS may be a potential intervention target for the prevention and treatment of NAFLD and T2DM.

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