3, 3'-Diindolylmethane alleviates steatosis and the progression of NASH partly through shifting the imbalance of Treg/Th17 cells to Treg dominance

Int Immunopharmacol. 2014 Dec;23(2):489-98. doi: 10.1016/j.intimp.2014.09.024. Epub 2014 Oct 1.


This study was designed to discuss the effects of 3, 3'-diindolylmethane (DIM) on methionine-choline-deficient (MCD)-diet induced mouse nonalcoholic steatohepatitis (NASH) and the potential mechanisms. NASH mice were administrated with or without DIM at different concentrations for 8 weeks. Both the in-vivo and in-vitro effects of DIM on Treg/Th17 imbalance during NASH progression were analyzed. The in-vivo blocking of CD25 or IL-17 was performed to respectively deplete respective function of Treg or Th17 subset. Besides, with the assistance of AhR antagonist CH223191 and anti-TLR4 neutralizing antibody, we designed the in-vitro DIM-incubation experiments to discuss the roles of aryl hydrocarbon receptor (AhR) (CYP1A1, CYP1B1) and toll-like receptor 4 (TLR4) on DIM's effects when shifting Treg/Th17 imbalance. Notably, in NASH mouse models, DIM alleviated hepatic steatosis and inflammation, and shifted the Treg/Th17 imbalance from MCD diet-induced Th17 dominance to Treg dominance. In-vitro, DIM not only significantly up-regulated the mRNAs of Foxp3 (Treg-specific) in purified spleen CD4(+) T cells, but also enhanced the immunosuppressive function of these Treg cells. Besides, DIM significantly up-regulated the proteins of CYP1A1 and CYP1B1 whereas down-regulated those of TLR4 on CD4(+) T cells from MCD-diet mice. Moreover, blocking AhR attenuated while blocking TLR4 enhanced the effects of DIM when regulating Treg/Th17 imbalance. Conclusively, DIM could be used as a potential therapeutic candidate to treat NASH based on its dramatic induction of Treg dominance to alleviate intra-hepatic inflammation, suggesting us a clue that the dietary cruciferous vegetables (containing abundant DIM) might exist as a protective factor for patients with NASH-related liver diseases.

Keywords: 3, 3′-diindolylmethane; Aryl hydrocarbon receptor; Nonalcoholic steatohepatitis; Regulatory T cells; Th17 cells; Toll like receptor 4.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CD4-Positive T-Lymphocytes
  • Cells, Cultured
  • Choline / administration & dosage
  • Diet / adverse effects
  • Female
  • Indoles / pharmacology*
  • Liver / cytology
  • Methionine / deficiency
  • Mice
  • Mice, Inbred C57BL
  • Non-alcoholic Fatty Liver Disease / drug therapy*
  • Non-alcoholic Fatty Liver Disease / etiology
  • Spleen / cytology
  • T-Lymphocytes, Regulatory / drug effects*
  • T-Lymphocytes, Regulatory / physiology
  • Th17 Cells / drug effects*
  • Th17 Cells / physiology
  • Toll-Like Receptor 4 / genetics
  • Toll-Like Receptor 4 / metabolism


  • Indoles
  • Tlr4 protein, mouse
  • Toll-Like Receptor 4
  • Methionine
  • Choline
  • 3,3'-diindolylmethane