Published online Jul 14, 2022. doi: 10.3748/wjg.v28.i26.3150
Peer-review started: October 26, 2021
First decision: April 16, 2022
Revised: April 25, 2022
Accepted: May 22, 2022
Article in press: May 22, 2022
Published online: July 14, 2022
Processing time: 260 Days and 4.9 Hours
Cholestasis is mild and common during liver diseases but is also a crucial triggering element of severe hepatopathy. As the predominant component of oral contraceptives (OCs) and hormone replacement therapy, 17α-ethinylestradiol (EE) is used as a model drug to induce murine intrahepatic cholestasis (IHC). The clinical counterpart of EE-induced IHC includes women who are taking OCs, postmenopausal replacement therapy, and susceptible pregnant women.
The significance of the local immune microenvironment in the liver has been emphasized because estrogens are immunomodulators that are metabolized in the liver.
The aim of the present study was to investigate the effects and mechanisms of natural killer T (NKT) cells in a murine model of EE-induced cholestatic hepatotoxicity.
Male C57BL/6J mice or invariant NKT (iNKT) cell deficiency (Jα18-/- mice) were administered with EE (10 mg/kg, subcutaneous) for 14 d.
Both Th1 and Th2 cytokines produced by NKT cells increased in the liver skewing toward a Th1 bias. The expression of the chemokine/chemokine receptor Cxcr6/Cxcl16, toll-like receptors, Ras/Rad, and PI3K/Bad signaling was upregulated after EE administration. EE also influenced bile acid synthase Cyp7a1, Cyp8b1, and tight junctions ZO-1 and Occludin, which might be associated with EE-induced cholestasis. iNKT cell deficiency (Jα18-/- mice) robustly alleviated cholestatic liver damage and lowered the expression of the abovementioned signaling pathways.
The present study demonstrated that hepatic NKT cells play a pathogenic role in EE-induced intrahepatic cholestasis, contributing to the development of the IHC mechanisms and the potential treatment targeting NKT cells.
Hepatic NKT cells and their Th1 cytokine production play a pathogenic role in a 14-d murine model of EE-induced intrahepatic cholestasis.