Astaxanthin inhibits the reduction of glycolysis during the activation of hepatic stellate cells

Aims: Hepatic stellate cells (HSCs) play an essential role in the development of liver fibrosis by producing extracellular matrix proteins, growth factors, and pro-inflammatory and pro-fibrogenic cytokines once activated. We previously demonstrated that astaxanthin (ASTX), a xanthophyll carotenoid, attenuates HSC activation. The objective of this study was to investigate whether there is a difference in glycolysis between quiescent and activated HSCs and the effect of ASTX on glycolysis during HSC activation.

Materials and methods: Mouse primary HSCs were activated for 7 days in the presence or absence of 25 μM of ASTX. Quiescent HSCs (qHSCs), 1 day after isolation, and activated HSCs (aHSCs) treated with/without ASTX were plated in a Seahorse XF24 cell culture microplate for Glycolysis Stress tests.

Key findings: aHSCs had significantly lower glycolysis, but higher glycolytic capacity, maximum capacity of glycolysis, and non-glycolytic acidification than qHSCs. Importantly, ASTX markedly increased glycolysis during HSC activation with a concomitant increase in lactate formation and secretion. Compared with qHSCs, aHSCs had significantly lower expression of glucose transporter 1, the major glucose transporter in HSCs, and its transcription factor hypoxia-inducible factor 1α, which was markedly increased by ASTX in aHSCs.

Significance: Our data suggest that ASTX may prevent the activation of HSCs by altering glycolysis and the expression of genes involved in the pathways.

Keywords: Astaxanthin; Energy metabolism; Glycolysis; Hepatic stellate cells.