Effects of cataractogenesis on the CDP-choline pathway: increased phospholipid synthesis in lenses from galactosemic rats and 13/N guinea pigs.
We investigated the effects of cataractogenesis on phospholipid (P-lipid) synthesis in sugar cataracts from galactosemic rats and in hereditary cataracts from 13/N guinea pigs. Cataractous lenses from rats fed a 50% galactose diet for 7 days were incubated 24 h with radiolabeled choline or ethanolamine and the P-lipids were extracted. The galactosemic cataracts synthesized twice as much phosphatidylcholine (PtdCho) as control rat lenses, and phosphatidylethanolamine synthesis also was increased. Similar analysis of cataractous lenses from 3-week-old 13/N guinea pigs showed a 3-fold increase in PtdCho synthesis compared with control lenses. In all cases, the P-lipid precursor pool was lower in cataracts than in control lenses. The increased P-lipid synthesis in these cataracts may represent a membrane repair response to cataractogenic stress.
Jernigan
Howard M
HM
Department of Molecular Sciences, University of Tennessee, Memphis, TN 38163, USA. hjernigan@utmem.edu
Blum
Penny S
PS
Chakrabarti
Ipsit
I
Su
Yin
Y
Zigler
J Samuel
JS
D000818:Animals; D001834:Body Water; D002386:Cataract / Q000139:chemically induced / Q000235:genetics / Q000378:metabolism*; D003566:Cytidine Diphosphate Choline / Q000378:metabolism*; D004983:Ethanolamines / Q000378:metabolism; D005693:Galactosemias / Q000378:metabolism*; D006168:Guinea Pigs; D007908:Lens, Crystalline / Q000378:metabolism*; D008297:Male; D010713:Phosphatidylcholines / Q000096:biosynthesis*; D010714:Phosphatidylethanolamines / Q000096:biosynthesis*; D010767:Phosphorylcholine / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D004983:Ethanolamines; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010767:Phosphorylcholine; C483858:phosphatidylethanolamine; D003566:Cytidine Diphosphate Choline; C005448:phosphorylethanolamine