肝臓星細胞によるビタミンAの代謝・貯蔵メカニズムとその意義(若手シンポジウム「ビタミン基礎研究の進展を担う若手研究者たち」,<特集>ビタミン基礎研究の進展を担う若手研究者たち(第64回大会若手シンポジウム))

概要

論文の詳細を見る
Hepatic stellate cells (HSCs), which are also known as vitamin A-storing cells, reside in a space between hepatocytes and liver sinusoids. Two proteins, cellular retinol-binding protein (CRBP) and lecithin:retinol acyltransferase (LRAT), are known to play an important role in vitamin A storage in HSCs, because retinol bound to CRBP is a good substrate for LRAT. After the discovery that HSCs are responsible for the development of liver fibrosis and subsequent liver cirrhosis, functions of HSCs in pathological conditions have been extensively studied. However, the roles of HSCs in physiological conditions remain to be elucidated. Here we present a hypothesis that an increased retinoid signaling in activated HSCs makes a feedback loop toward vitamin A restoration. The hypothesis is based on our previous finding that HSCs acquire retinoid responsiveness after activation in vitro by post-transcriptional up regulation of retinoic acid receptor alpha gene expression
2013-01-25