High-dose zinc to terminate angina pectoris: a review and hypothesis for action by ICAM inhibition.

We reviewed the literature related to the effects of high-dose zinc in arteriosclerosis-induced angina pectoris. Lipid peroxidation and LDL oxidation are believed to be critical for arteriosclerosis, and consequently angina pectoris. Administration of biologically available zinc was a beneficial treatment in a significant percentage of patients with severely symptomatic, inoperable atherosclerotic disease. In these patients, there was no difference in zinc concentration between patients with and without atherosclerosis in whole blood, erythocytes or hair, but there was a major difference between normal aorta and diseased aortas (40.6 ppm zinc in normal aorta vs. 23.2 ppm zinc in atherosclerotic aorta, 40.6 ppm zinc in normal aorta vs. 19.4 ppm zinc in atherosclerotic aneurysm aorta, and no difference between normal and aneurysm aorta), although copper was low in aneurysm aorta. Medication with high-dose zinc sulfate to raise zinc serum concentrations from 95 to 177 microg/dl resulted in objective improvement in 12 of 16 of these patients, including a patient that also had Raynaud's disease. Long term environmental exposure to zinc resulted in a 40% reduction in the incidence of angina of effort compared to people not exposed to environmental zinc (P<0.01) and a 40% reduction in the incidence of probable ischemia in exercise (P<0.001). Lead had no effect while cadmium exposure resulted in more than tripling the incidence of angina of effort (P<0.001). The antioxidative action of zinc prevents oxidation of LDL cholesterol and consequently stops the main mechanism of atherogenesis. Zinc blocks calcium and its several actions on atherogenesis. Increased amounts of cytotoxic cytokines such as TNF-alpha, IL-beta and IL-8, often produced in the elderly, are blocked by high-dose zinc. We hypothesize that higher serum concentrations of LDL cholesterol resulting from administration of 300 mg of zinc per day is caused by a release of low density cholesterol from cardiovascular tissues, beneficially flushing it into the serum where it is readily observed, thus decreasing arteriosclerosis, increasing circulation, terminating angina pectoris and restoring more youthful cardiac function. Although prevention of cholesterol-induced arteriosclerosis by zinc is predicted from findings related to oxidative stress and lipid peroxidation, removal of LDL might be attributable to action of ionic zinc on ICAM inhibition. In stark contrast to current practice, high-dose zinc should be considered as basic in the strategy of prophylaxis and therapy of the atherosclerosis process to terminate angina pectoris and restore youthful cardiac function.