PT  - JOURNAL ARTICLE
AU  - Zhi Zhong
AU  - Xiangli Li
AU  - Shunhei Yamashina
AU  - Moritz von Frankenberg
AU  - Nobuyuki Enomoto
AU  - Kenichi Ikejima
AU  - Monica Kolinsky
AU  - James A. Raleigh
AU  - Ronald G. Thurman
TI  - Cyclosporin A Causes a Hypermetabolic State and Hypoxia in the Liver: Prevention by Dietary Glycine
DP  - 2001 Dec 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 858--865
VI  - 299
IP  - 3
4099  - http://jpet.aspetjournals.org/content/299/3/858.short
4100  - http://jpet.aspetjournals.org/content/299/3/858.full
SO  - J Pharmacol Exp Ther2001 Dec 01; 299
AB  - Acute cyclosporin A (CsA) treatment inhibits mitochondrial respiration, yet effects of chronic treatment remain unclear. Accordingly, the effects of chronic CsA on oxygen metabolism in perfused rat liver and isolated mitochondria were investigated. Basal rates of oxygen uptake of around 120 μmol/g/h in isolated perfused livers from vehicle-treated controls were elevated about 1.6-fold by chronic CsA treatment. In the presence of ammonium chloride, a substrate for urea synthesis, oxygen uptake was about 150 μmol/g/h and was increased about 1.7-fold by CsA, indicating that chronic CsA treatment causes a robust hypermetabolic state in the liver. In isolated mitochondria, state 3 rates of oxygen uptake were increased about 1.6-fold by chronic CsA treatment. Since significant increases in oxygen consumption could cause hypoxia, the hypoxia marker pimonidazole was given. Pimonidazole binding in the liver was increased about 3-fold by chronic CsA. Moreover, intracellular calcium in Kupffer cells isolated from vehicle-treated rats was not altered by CsA addition; however, in cells isolated from chronic CsA-treated rats, CsA increased intracellular calcium about 15-fold and prostaglandin E2(PGE2) production 3.5-fold. Importantly, dietary glycine (5%) largely blocked chronic CsA-induced activation of Kupffer cells, blunted production of PGE2, prevented the hypermetabolic state, and minimized tissue hypoxia. Taken together, it is concluded that chronic CsA treatment causes a hypermetabolic state leading to hypoxia and injury to the liver. It is hypothesized that CsA activates Kupffer cells and increases production of PGE2, which alters mitochondria leading to a hypermetabolic state. Glycine inhibits activation of Kupffer cells thus preventing liver injury. The American Society for Pharmacology and Experimental Therapeutics