Probiotics counteract the expression of hepatic profibrotic genes via the attenuation of TGF-β/SMAD signaling and autophagy in hepatic stellate cells

PLoS One. 2022 Jan 20;17(1):e0262767. doi: 10.1371/journal.pone.0262767. eCollection 2022.

Abstract

Hepatic fibrosis is caused by the increased accumulation and improper degradation of extracellular matrix (ECM) proteins in the liver. Hepatic stellate cells (HSCs) activation is a key process in initiating hepatic fibrosis and can be ameliorated by the administration of probiotic strains. This study hypothesized that LAB strains (Lactiplantibacillus plantarum, Lactobacillus brevis, and Weissella cibaria) might attenuate pro-fibrogenic cytokine TGF-β mediated HSCs activation and induce collagen deposition, expression of other fibrogenic/inflammatory markers, autophagy, and apoptotic processes in vitro. Few studies have evaluated the probiotic effects against fibrogenesis in vitro. In this study, TGF-β exposure increased collagen deposition in LX-2 cells, but this increase was diminished when the cells were pretreated with LAB strains before TGF-β stimulation. TGF-β not only increased collagen deposition, but it also significantly upregulated the mRNA levels of Col1A1, alpha-smooth muscle actin (α-SMA), matrix metalloproteinases-2 (MMP-2), IL-6, CXCL-8, CCL2, and IL-1β in LX-2 cells. Pretreatment of the cells with LAB strains counteracted the TGF-β-induced pro-fibrogenic and inflammatory markers by modulating SMAD-dependent and SMAD-independent TGF-β signaling. In addition, LX-2 cells exposed to TGF-β induced the autophagic and apoptotic associated proteins that were also positively regulated by the LAB strains. These findings suggest that LAB can attenuate TGF-β signaling that is associated with liver fibrogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Autophagy / drug effects*
  • Cell Line
  • Collagen / metabolism
  • Gene Expression / drug effects*
  • Hepatic Stellate Cells / drug effects*
  • Hepatic Stellate Cells / metabolism
  • Humans
  • Liver / drug effects*
  • Liver / metabolism
  • Liver Cirrhosis / genetics*
  • Liver Cirrhosis / metabolism
  • Probiotics / administration & dosage*
  • Signal Transduction / drug effects*
  • Smad Proteins / metabolism
  • Transforming Growth Factor beta / metabolism

Substances

  • Smad Proteins
  • Transforming Growth Factor beta
  • Collagen

Grants and funding

This study was supported by a National Research Foundation (NRF) of Korea grant funded by the Korean Government to PK (NRF-2019R11A1A01058795), and also was supported by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health &Welfare, Republic of Korea (grant number: HF20C0020) to HK (NRF-2019R1A2B5B01070365) as well as by the Korean Research Fellowship (KRF) program of the NRF (2016H1D3A1937971). The funders did not play any role in the study design, data collection, and analysis, decision to publish, or preparation of the manuscript.