Loss of α-catenin elicits a cholestatic response and impairs liver regeneration

Sci Rep. 2014 Oct 30:4:6835. doi: 10.1038/srep06835.

Abstract

The liver is unique in its capacity to regenerate after injury, during which hepatocytes actively divide and establish cell-cell contacts through cell adhesion complexes. Here, we demonstrate that the loss of α-catenin, a well-established adhesion component, dramatically disrupts liver regeneration. Using a partial hepatectomy model, we show that regenerated livers from α-catenin knockdown mice are grossly larger than control regenerated livers, with an increase in cell size and proliferation. This increased proliferation correlated with increased YAP activation, implicating α-catenin in the Hippo/YAP pathway. Additionally, α-catenin knockdown mice exhibited a phenotype reminiscent of clinical cholestasis, with drastically altered bile canaliculi, elevated levels of bile components and signs of jaundice and inflammation. The disrupted regenerative capacity is a result of actin cytoskeletal disorganisation, leading to a loss of apical microvilli, dilated lumens in the bile canaliculi, and leaky tight junctions. This study illuminates a novel, essential role for α-catenin in liver regeneration.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / metabolism
  • Adaptor Proteins, Signal Transducing / metabolism
  • Animals
  • Bile Canaliculi / pathology
  • Bile Canaliculi / ultrastructure
  • Cell Cycle Proteins
  • Cell Proliferation
  • Cholestasis / blood
  • Cholestasis / genetics*
  • Female
  • Hepatocytes / physiology
  • Liver Regeneration / physiology*
  • Mice
  • Mice, Knockout
  • Microvilli / ultrastructure
  • Models, Animal
  • Phosphoproteins / metabolism
  • YAP-Signaling Proteins
  • alpha Catenin / deficiency
  • alpha Catenin / genetics*

Substances

  • Actins
  • Adaptor Proteins, Signal Transducing
  • Cell Cycle Proteins
  • Phosphoproteins
  • YAP-Signaling Proteins
  • Yap1 protein, mouse
  • alpha Catenin