Background: Recent evidence demonstrates that alcohol activates the mechanistic target of rapamycin (mTOR) and impairs hepatic transcription factor EB (TFEB) reducing autophagy and contributing to alcohol-induced liver injury. Trehalose, a disaccharide, activates TFEB and protects against diet-induced nonalcoholic fatty liver disease in mice. The aim of the present study was to investigate whether trehalose would reverse the impairment of TFEB induced by alcohol and protect against alcohol-induced liver injury.
Methods: Male C57BL/6J mice were subjected to chronic-plus-binge (Gao-binge) alcohol feeding with and without trehalose supplementation. Some mice were also administrered Alda-1, an aldehyde dehydrogenase 2 agonist.
Results: We found that Alda-1 did not affect Gao-binge alcohol-induced mTOR activation and impaired TFEB in mouse livers. Trehalose increased TFEB nuclear translocation, elevated levels of LC3-II and lysosomal proteins in mouse livers and cultured AML12 cells, confirming the activation of TFEB by trehalose. However, trehalose did not improve the impairment in TFEB induced by Gao-binge alcohol. Both Alda-1 and trehalose failed to protect against Gao-binge alcohol-induced steatosis and liver injury, based on the serum levels of alanine aminotransferase (ALT), histological analysis, and levels of hepatic triglyceride. Interestingly, trehalose increased expression of pro-inflammatory genes in mouse macrophage RAW264.7 cells and slightly increased the infiltration of hepatic neutrophils and inflammatory cytokine gene expression in Gao-binge alcohol-fed mice livers.
Conclusions: Trehalose fails to improve the impaired TFEB induced by Gao-binge alcohol and does not protect against alcohol-induced liver injury.
Keywords: ALDH2; autophagy; ethanol; liver injury; steatosis.
© 2021 by the Research Society on Alcoholism.