Lipids in Health and Disease

In order to investigate the effects of lead exposure on risk of cardiovascular disease during occupational exposure to this metal, plasma cholesterol and its fractions as high-density liporotein (HDL), low-density liporotein (LDL) and triglyceride were determined in various artisans in Abeokuta, Nigeria who have been shown to be occupationally exposed to lead and these were related to blood lead levels. Increased risk of cardiovascular disease was observed in the artisans. Total cholesterol in the artisans was between 1.5 and 2.0 times higher in the artisans than that present in controls while LDL cholesterol was between 1.6 and 2.4 times higher in the artisans when compared with control subjects [p 0.05]. A significant positive correlation was observed between blood lead and total cholesterol on one hand [r = 0.372; p = 3.0 × 10-5] and blood lead and LDL cholesterol on the other hand [r = 0.283; p = 0.001]. LDL/HDL cholesterol ratio was also higher in the artisans when compared with control. Blood pressure (systolic and diastolic) and other anthropometric parameters were not significantly different between the artisans and the control subjects [p > 0.05]. Results suggest that lead exposure increases cholesterol synthesis and transport to peripheral tissues whereas reverse cholesterol transport to the liver is not affected. Introduction Studies in both humans and animals indicate that lipid metabolism is altered in chronic lead exposure [1-6]. The pathophysiological mechanisms involved in this leadinduced alterations are not completely understood. Lead has been shown to accelerate lipid oxidation in the presence of hemoglobin or Fe2+ [7,8]. Lead was also shown to enhance Fe2+-initiated lipid oxidation in liposomes, erythrocytes, microsomal fractions and rat brain homogenates [1,7,9]. Altered fatty acid composition of erythrocyte membranes has also been demonstrated in chronic lead exposure [5,10,11]. It has also been demonstrated that lead exposure affects levels of galactolipid metabolic enzymes in the developing rat brain resulting in myelin defects [3]. All these observations are largely more suggestive than conclusive about lead-induced alterations in lipid metabolism. Lead poisoning is presently becoming the most common disease of environmental origin and is increasing very Published: 28 September 2005 Lipids in Health and Disease 2005, 4:19 doi:10.1186/1476-511X-4-19 Received: 31 August 2005 Accepted: 28 September 2005 This article is available from: http://www.lipidworld.com/content/4/1/19 © 2005 Ademuyiwa et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.