title: Deficiency of inducible nitric oxide synthase exacerbates hepatic fibrosis in mice fed high-fat diet.
abstract: The role of inducible nitric oxide synthase (iNOS) in the progression of fibrosis during nonalcoholic steatohepatitis remains to be elucidated. This study examined the role of iNOS in the progression of fibrosis during steatohepatitis by comparing iNOS knockout (iNOS(-/-)) and wild-type (iNOS(+/+)) mice that were fed a high-fat diet. Severe fatty metamorphosis developed in the liver of iNOS(+/+) and iNOS(-/-) mice. Fibrotic changes were marked in iNOS(-/-) mice. Gelatin zymography showed that pro MMP-2 and pro MMP-9 protein expressions were more highly induced in iNOS(+/+) mice than in iNOS(-/-) mice. Active forms of MMP-2 and MMP-9 were clearly present only in the liver tissue of iNOS(+/+) mice. In situ zymography showed strong gelatinolytic activities in the liver tissue of iNOS(+/+) mice, but only spotty activity in iNOS(-/-)mice. iNOS may attenuate the progression of liver fibrosis in steatohepatitis, in part by inducing MMP-2 and MMP-9 expression and augmenting their activity.
authors.affiliation: Department of Physiology, School of Medicine, Tokai University, Bohseidai, Isehara, Kanagawa 259-1193, Japan.
authors.forename: Yi
authors.initials: Y
authors.lastname: Chen
authors.forename: Shigenari
authors.initials: S
authors.lastname: Hozawa
authors.forename: Sadaaki
authors.initials: S
authors.lastname: Sawamura
authors.forename: Shinkichi
authors.initials: S
authors.lastname: Sato
authors.forename: Naoto
authors.initials: N
authors.lastname: Fukuyama
authors.forename: Chizuko
authors.initials: C
authors.lastname: Tsuji
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Mine
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Okada
authors.forename: Ryuzaburo
authors.initials: R
authors.lastname: Tanino
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Ogushi
authors.forename: Hiroe
authors.initials: H
authors.lastname: Nakazawa
mesh_terms: D000818:Animals; D004041:Dietary Fats / Q000378:metabolism*; D005234:Fatty Liver / Q000150:complications / Q000378:metabolism*; D008099:Liver / Q000378:metabolism*; D008103:Liver Cirrhosis / Q000209:etiology / Q000378:metabolism*; D020782:Matrix Metalloproteinases / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D019001:Nitric Oxide Synthase / Q000172:deficiency*; D052247:Nitric Oxide Synthase Type II; D011347:Procollagen / Q000378:metabolism*; D012720:Severity of Illness Index
chemical_list: D004041:Dietary Fats; D011347:Procollagen; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse; D020782:Matrix Metalloproteinases