RT Journal Article SR Electronic T1 Long-acting human serum albumin-thioredoxin fusion protein suppresses bleomycin-induced pulmonary fibrosis progression JF Journal of Pharmacology and Experimental Therapeutics JO J Pharmacol Exp Ther FD American Society for Pharmacology and Experimental Therapeutics SP jpet.112.201814 DO 10.1124/jpet.112.201814 A1 Ryota Tanaka A1 Hiroshi Watanabe A1 Azusa Kodama A1 Victor Tuan Giam Chuang A1 Yu Ishima A1 Keisuke Hamasaki A1 Ken-ichiro Tanaka A1 Tohru Mizushima A1 Masaki Otagiri A1 Toru Maruyama YR 2013 UL http://jpet.aspetjournals.org/content/early/2013/02/26/jpet.112.201814.abstract AB Idiopathic pulmonary fibrosis (IPF) is thought to involve inflammatory cells and reactive oxygen species (ROS), such as superoxide anion radical (O2·-). There is currently no effective treatment for IPF. We previously developed a human serum albumin (HSA)-thioredoxin 1 (Trx) fusion protein (HSA-Trx), designed to overcome the unfavorable pharmacokinetic and short pharmacological properties of Trx, an anti-oxidative and anti-inflammatory protein. In this study, we examined the therapeutic effect of HSA-Trx on an IPF animal model of bleomycin (BLM)-induced pulmonary fibrosis. A pharmacokinetic study of HSA-Trx or Trx in BLM mice showed that the plasma retention and lung distribution of Trx was markedly improved by fusion with HSA. A weekly intravenous administration of HSA-Trx, but not Trx, ameliorated BLM-induced fibrosis as evidenced by a histopathological analysis and pulmonary hydroxyproline levels. HSA-Trx suppressed active-TGF-β levels in the lung and inhibited the increase of inflammatory cells in BALF, pulmonary inflammatory cytokines and oxidative stress markers. An in vitro EPR experiment using PMA-stimulated neutrophils confirmed the O2·- scavenging ability of HSA-Trx. Furthermore, post-treatment of HSA-Trx had a suppressive effect against BLM-induced fibrosis. These results suggest that HSA-Trx has potential as a novel therapeutic agent for IPF, due to its long-acting anti-oxidative and anti-inflammatory modulation effects.