Aabdallah Dalaal M, Eid Nihad I
Department of Pharmacology & Toxicology, Faculty of Pharmacy, Cairo University, Cairo, Egypt.
J Biochem Mol Toxicol. 2004;18(5):273-8. doi: 10.1002/jbt.20037.
A close correlation exists between ischemia/reperfusion (I/R)-induced insult and the release of free radicals. Lecithin is a polyunsaturated phosphatidylcholine that corresponds to the phosphatidylcholine molecule. Phosphatidylcholines are high-energy functional and structural elements of all biologic membranes. alpha-Tocopherol is the major lipid-soluble chain-breaking antioxidant in the body tissues and effectively protects against neuronal damage. Therefore, we studied the effect of lecithin (300 mg/kg, p.o., 14 days) and alpha-tocopherol (200 mg/kg, p.o., 14 days), alone or in combination, on the brain redox state during I/R. Adult male Wistar rats were subjected to global ischemia by the occlusion of the two carotid arteries 24 h after the last dose of drug administration. Reperfusion was carried out 1 h after induction of ischemia and lasted for another hour. Brain lipid peroxides (MDA) and glutathione (GSH) contents, as well as superoxide dismutase (SOD) and catalase (CAT) activities were assessed. The results showed that I/R elevated brain lipid peroxides content which was accompanied by a reduction in both antioxidant enzyme activities, however, brain GSH level remained unaltered. Lecithin, alpha-tocopherol and their combination restored MDA content, as well as CAT activity with a slight tendency to normalize SOD activity. We conclude that lecithin has a possible neuroprotective effect partly through its antioxidant action which is comparable to that of alpha-tocopherol.
缺血/再灌注(I/R)诱导的损伤与自由基的释放之间存在密切关联。卵磷脂是一种多不饱和磷脂酰胆碱,与磷脂酰胆碱分子相对应。磷脂酰胆碱是所有生物膜的高能功能和结构成分。α-生育酚是人体组织中主要的脂溶性链断裂抗氧化剂,能有效保护神经元免受损伤。因此,我们研究了卵磷脂(300毫克/千克,口服,14天)和α-生育酚(200毫克/千克,口服,14天)单独或联合使用对I/R期间脑氧化还原状态的影响。成年雄性Wistar大鼠在最后一次给药后24小时通过结扎两条颈动脉进行全脑缺血。缺血诱导1小时后进行再灌注,并持续另外1小时。评估脑脂质过氧化物(MDA)和谷胱甘肽(GSH)含量以及超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性。结果表明,I/R使脑脂质过氧化物含量升高,同时伴随着两种抗氧化酶活性的降低,然而,脑GSH水平保持不变。卵磷脂、α-生育酚及其组合恢复了MDA含量以及CAT活性,SOD活性有轻微的恢复正常的趋势。我们得出结论,卵磷脂可能具有神经保护作用,部分是通过其抗氧化作用,这与α-生育酚相当。