Hydrogen sulfide alleviates ischemia induced liver injury by repressing the SPHK1/S1P pathway

Liang Chen; Bo Lin; Jianrong Yang; Lin Zhong; Xiaolan Xiong; Xiaolong Wang

doi:10.21037/atm-22-6460

Hydrogen sulfide alleviates ischemia induced liver injury by repressing the SPHK1/S1P pathway

Ann Transl Med. 2023 Jan 31;11(2):73. doi: 10.21037/atm-22-6460.

Authors

Liang Chen¹, Bo Lin¹, Jianrong Yang¹, Lin Zhong¹, Xiaolan Xiong¹, Xiaolong Wang¹

Affiliation

¹ Department of General Surgery, Affiliated Huadu Hospital, Southern Medical University (People's Hospital of Huadu District), Guangzhou, China.

Abstract

Background: Ischemia/reperfusion (I/R) induced liver injury is a severe pathological process which frequently occurs during clinical hepatic operations. The current study investigated the protective function and underlying mechanisms of hydrogen sulfide (H₂S) in I/R induced liver injury.

Methods: The effects of H₂S were examined using the fibroblast-like rat liver cell line BRL-3A (the name of normal hepatocytes in rats) cultured under hypoxic conditions and an I/R rat model. The viability of BRL-3A cells was assessed using the methylthiazolyldiphenyl-tetrazolium (MTT) assay and Hoechst analysis. The expression of C/EBP homologous protein (CHOP), sphingosine kinase 1 (SPHK1), and sphingosine 1-phosphate (S1P) were determined in hypoxic BRL-3A cells with or without H₂S treatment. CHOP was overexpressed in hypoxic BRL-3A cells to further evaluate whether H₂S protected the liver against I/R injury by decreasing endoplasmic reticulum (ER) stress. Finally, the inflammation levels in the serum and the histopathological changes of liver were examined in the I/R rat model to evaluate the therapeutic function of H₂S on I/R induced liver injury in vivo.

Results: H₂S alleviated hypoxic damage in BRL-3A cells. In addition, hypoxia increased the expression of CHOP, SPHK1, and S1P in BRL-3A cells, and this was abolished by H₂S pretreatment. Notably, overexpression of CHOP significantly inhibited the effect of H₂S on the viability of BRL-3A cells during hypoxia. Overall, H₂S effectively protected against I/R induced liver injury, decreased the inflammatory responses, and attenuated apoptosis of hepatocyte via inhibiting the ER stress response.

Conclusions: These findings demonstrated that pre-treatment of H₂S protected against I/R induced liver injury by repressing the SPHK1/S1P pathway via inhibition of ER stress, suggesting an effective therapeutic method for the treatment of I/R induced liver injury.

Keywords: Ischemia/reperfusion induced liver injury; endoplasmic reticulum stress (ER stress); hydrogen sulfide (H2S); sphingosine 1-phosphate (S1P); sphingosine kinase 1 (SPHK1).