# Amniotic fluid reduces liver fibrosis by attenuating hepatic stellate cell activation

## TL;DR

Amniotic fluid helps reduce liver scarring by preventing harmful cell changes linked to fibrosis in mice and lab models.

## Contribution

Demonstrates that cell-free amniotic fluid can safely reduce liver fibrosis by inhibiting stellate cell activation in multiple models.

## Key findings

- cfAF reduced liver fibrosis and weight loss in mice with chronic liver damage.
- cfAF treatment lowered EMT and MFA biomarkers in hepatic spheroids and HSC cultures.
- Multiomics analyses showed cfAF attenuates TGFβ-induced MFA and inflammation.

## Abstract

Regardless of the source of injury or metabolic dysfunction, fibrosis is a frequent driver of liver pathology. Excessive liver fibrosis is caused by persistent activation of hepatic stellate cells (HSCs), which is defined by myofibroblast activation (MFA) and the epithelial-mesenchymal transition (EMT). Strategies to prevent or reverse this HSC phenotype will be critical for successful treatment of liver fibrosis. We have previously shown that full-term, cell-free human amniotic fluid (cfAF) inhibits MFA and EMT in fibroblasts in vitro. We hypothesize that cfAF treatment can attenuate HSC activation and limit liver fibrosis. We tested if cfAF could prevent liver fibrosis or HSC activation in murine models of liver damage, 3-dimensional hepatic spheroids, and HSC cultures. Administering cfAF prevented weight loss and the extent of fibrosis in mice with chronic liver damage without stimulating deleterious immune responses. Gene expression profiling and immunostaining indicated that cfAF administration in carbon tetrachloride-treated mice reduced EMT- and MFA-related biomarker abundance and modulated transcript levels associated with liver metabolism, immune regulatory pathways, and cell signaling. cfAF treatment lowered MFA biomarker levels in a dose-dependent manner in ex vivo hepatic spheroids. Treating HSCs with cfAF in vitro strongly repressed EMT. Multiomics analyses revealed that it also attenuates TGFβ-induced MFA and inflammation-associated processes. Thus, cfAF treatment prevents liver fibrosis by safeguarding against persistent HSC activation. These findings suggest that cfAF may be a safe and effective therapy for reducing liver fibrosis and preventing the development of cirrhosis and/or hepatocellular carcinoma.

Graphical Abstract Alt Text: Graphical abstract showing study results where cell-free amniotic fluid (cfAF) reduces stellate cell activation by reducing epithelial-mesenchymal transition (EMT) and myofibroblast activation (MFA) in multiple models of liver fibrosis.