Susceptibility of rat retina acyl‐CoA: 1‐acyl‐sn‐glycero‐3‐phosphocholine O‐acyltransferase and CTP:phosphocholine cytidylyltransferase activity to lipid peroxidation and hydroperoxide treatment

FEBS Letters

Lupo, Gabriella¹  Sipione, Simonetta¹  Anfuso, Carmelina D.¹  Alberghina, Mario¹ 

[1] Institute of Biochemistry, Faculty of Medicine, University of Catania, Viale Andrea Doria 6, 95125 Catania, Italy

关键词: Retina;    Lipid peroxidation;    Acyltransferase;    Cytidylyltransferase;    Phospholipids;   

DOI  :  10.1016/0014-5793(94)00519-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Two enzyme activities involved in phospholipid metabolism in the rat retina were determined after in vivo and in vitro peroxidation according to several model systems. The in vivo models were based on: (i) intravenous administration of a sonicated emulsion of phospholipid and linoleate photooxidized mixture to normal rat for a period of one week; (ii) acute injection of Fe²⁺ solution (20 mM) or (iii) 0.5 mg of hydroperoxylinoleate into the vitreous body, and collection of retinal tissue 4 h or 4 days later, respectively. Oleoyl CoA:lysophosphatidylcholine acyltransferase activity was unchanged or exhibited significant inhibition. On the contrary, CTP:phosphocholine cytidylyltransferase activity was stimulated. By incubating in vitro the retina with: (i) Fe²⁺-ascorbate; (ii) photooxidized phospholipid mixture (0.1–5 mM) or individual phospholipid classes; (iii) hydroperoxylinoleate (0.25–2 mM), with or without Fe²⁺, a significant inactivation of acyltransferase (six-fold maximum loss of initial activity) and a slight stimulation of cytidylyltransferase were seen. Altogether, the results suggest that in situ oxygen radical generation by a variety of agents irreversibly perturbs enzymes and/or membrane structures in which the enzymes are inserted; these events may be a causal factor in retinal degeneration accompanying some ocular diseases.

【 授权许可】

Unknown