Plasma lysophosphatidic acid level and serum autotaxin activity are increased in liver injury in rats in relation to its severity.
Lysophosphatidic acid (LPA) is a lipid mediator with multiple biological actions. We have reported that LPA stimulates hepatic stellate cell proliferation and inhibits DNA synthesis in hepatocytes, suggesting that LPA might play some role in the liver. We have found that plasma LPA level and serum autotaxin (ATX) activity were increased in patients with chronic hepatitis C. However, the clinical significance of LPA and its synthetic enzyme, autotaxin (ATX), is still unclear. To determine whether the increase of plasma LPA level and serum ATX activity might be found generally in liver injury, we examined the possible modulation of them in the blood in rats with various liver injuries. Plasma LPA level and serum ATX activity were increased in carbon tetrachloride-induced liver fibrosis correlatively with fibrosis grade, in dimethylnitrosamine-induced acute liver injury correlatively with serum alanine aminotransferase level or in 70% hepatectomy as early as 3 h after the operation. Plasma LPA level was correlated with serum ATX activity in rats with chronic and acute liver injury. ATX mRNA in the liver was not altered in carbon tetrachloride-induced liver fibrosis. Plasma LPA level and serum ATX activity are increased in various liver injuries in relation to their severity. Whether increased ATX and LPA in the blood in liver injury is simply a result or also a cause of the injury should be further clarified.
Watanabe
Naoko
N
Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8655, Japan.
Ikeda
Hitoshi
H
Nakamura
Kazuhiro
K
Ohkawa
Ryunosuke
R
Kume
Yukio
Y
Tomiya
Tomoaki
T
Tejima
Kazuaki
K
Nishikawa
Takako
T
Arai
Masahiro
M
Yanase
Mikio
M
Aoki
Junken
J
Arai
Hiroyuki
H
Omata
Masao
M
Fujiwara
Kenji
K
Yatomi
Yutaka
Y
D000818:Animals; D002251:Carbon Tetrachloride / Q000633:toxicity; D006498:Hepatectomy; D008099:Liver / Q000187:drug effects*; D008246:Lysophospholipids / Q000097:blood*; D008297:Male; D010727:Phosphoric Diester Hydrolases / Q000097:blood* / Q000235:genetics; D011755:Pyrophosphatases / Q000097:blood* / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D000099189:Lysophospholipase D
D002251:Carbon Tetrachloride; D008246:Lysophospholipids; D010727:Phosphoric Diester Hydrolases; D011755:Pyrophosphatases; D012333:RNA, Messenger; D000099189:Lysophospholipase D; C032881:lysophosphatidic acid