β-Elemene Attenuates Renal Fibrosis in the Unilateral Ureteral Obstruction Model by Inhibition of STAT3 and Smad3 Signaling via Suppressing MyD88 Expression

Int J Mol Sci. 2022 May 16;23(10):5553. doi: 10.3390/ijms23105553.

Abstract

Renal fibrosis is a chronic pathological process that seriously endangers human health. However, the current therapeutic options for this disease are extremely limited. Previous studies have shown that signaling factors such as JAK2/STAT3, Smad3, and Myd88 play a regulatory role in renal fibrosis, and β-elemene is a plant-derived sesquiterpenoid organic compound that has been shown to have anti-inflammatory, anti-cancer, and immunomodulatory effects. In the present study, the anti-fibrotic effect of β-elemene was demonstrated by in vivo and in vitro experiments. It was shown that β-elemene inhibited the synthesis of extracellular matrix-related proteins in unilateral ureteral obstruction mice, and TGF-β stimulated rat interstitial fibroblast cells, including α-smooth muscle actin, vimentin, and connective tissue growth factor, etc. Further experiments showed that β-elemene reduced the expression levels of the above-mentioned fibrosis-related proteins by blocking the phosphorylation of JAK2/STAT3, Smad3, and the expression or up-regulation of MyD88. Notably, knockdown of MyD88 attenuated the phosphorylation levels of STAT3 and Smad3 in TGF-β stimulated NRK49F cell, which may be a novel molecular mechanism by which β-elemene affects renal interstitial fibrosis. In conclusion, this study elucidated the anti-interstitial fibrosis effect of β-elemene, which provides a new direction for future research and development of drugs related to chronic kidney disease.

Keywords: Myd88; STAT3; Smad3; renal fibrosis; β-elemene.

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism
  • Animals
  • Cell Line
  • Fibrosis
  • Mice
  • Myeloid Differentiation Factor 88* / metabolism
  • Rats
  • Renal Insufficiency, Chronic* / metabolism
  • STAT3 Transcription Factor* / antagonists & inhibitors
  • STAT3 Transcription Factor* / metabolism
  • Sesquiterpenes* / pharmacology
  • Smad3 Protein* / antagonists & inhibitors
  • Smad3 Protein* / metabolism
  • Transforming Growth Factor beta / metabolism
  • Ureteral Obstruction* / complications
  • Ureteral Obstruction* / drug therapy
  • Ureteral Obstruction* / metabolism

Substances

  • Adaptor Proteins, Signal Transducing
  • Myd88 protein, mouse
  • Myd88 protein, rat
  • Myeloid Differentiation Factor 88
  • STAT3 Transcription Factor
  • Sesquiterpenes
  • Smad3 Protein
  • Smad3 protein, mouse
  • Smad3 protein, rat
  • Stat3 protein, mouse
  • Stat3 protein, rat
  • Transforming Growth Factor beta
  • beta-elemene