Department of Biochemistry, University of Agriculture, Abeokuta, Nigeria.
Environ Toxicol Pharmacol. 2004 Jul;17(3):169-76. doi: 10.1016/j.etap.2004.04.003.
In order to study the ameliorative effects of ascorbic acid in chronic lead poisoning, petrol station attendants and auto-mechanics in Abeokuta, Nigeria, who have been shown to be occupationally exposed to lead and university students (serving as control), were supplemented daily with 500mg ascorbic acid for 2 weeks. Blood and urine samples were collected from the subjects before and after ascorbic acid regimen and analysed for lead and biochemical effects associated with lead toxicity. The 2-week ascorbic acid supplementation resulted in a significant (P < 0.05) reduction in blood lead in the occupationally exposed subjects. The reduction in blood lead amounted to 57% in male petrol station attendants, 50% in female petrol station attendants and 44% in the auto-mechanics. Urinary excretion of lead increased remarkably in the occupationally exposed subjects (P < 0.05). The biochemical effects associated with the toxic effects of lead also responded positively to the ascorbic acid regimen. Plasma and urine aminolevulinic acid (ALA) were reduced significantly (P < 0.05) by as much as 55% and 57% respectively. Plasma calcium also increased significantly (P < 0.05) in the subjects. Decreased levels of reduced glutathione (GSH) and hemoglobin observed in the occupationally exposed subjects were reversed by ascorbic acid. Glutathione-S-transferase (GST) and catalase (CAT) activities were not affected. Our findings indicate that ascorbic acid may be useful as an economical and convenient prophylactic agent for lead poisoning.
为了研究抗坏血酸对慢性铅中毒的改善作用，我们选择了尼日利亚阿贝库塔的加油站工作人员和汽车修理工（这些人被证明职业性接触铅）以及大学生（作为对照组）进行研究，让他们每天补充 500mg 的抗坏血酸，为期两周。在补充抗坏血酸之前和之后，我们从这些研究对象中采集了血液和尿液样本，并对其进行了分析，以评估铅暴露和与铅毒性相关的生化效应。为期两周的抗坏血酸补充显著降低了职业性暴露人群的血铅（P<0.05）。在男性加油站工作人员中，血铅降低了 57%，在女性加油站工作人员中降低了 50%，在汽车修理工中降低了 44%。职业性暴露人群的尿液铅排泄量显著增加（P<0.05）。与铅毒性相关的生化效应也对抗坏血酸补充方案做出了积极的响应。血浆和尿液中的氨基乙酰丙酸（ALA）分别显著降低了 55%和 57%。研究对象的血浆钙水平也显著升高（P<0.05）。在职业性暴露人群中观察到的还原型谷胱甘肽（GSH）和血红蛋白水平下降，在补充抗坏血酸后得到了逆转。谷胱甘肽-S-转移酶（GST）和过氧化氢酶（CAT）的活性没有受到影响。我们的研究结果表明，抗坏血酸可能是一种有用的、经济实惠且方便的铅中毒预防药物。
