Calcium metabolism fluoride

These studies have shown that phosphorus, magnesium and fluoride In the doses used had no effect on the bloavailablllty of calcium, while large doses of zinc given during a low calcium Intake Inhibited the Intestinal absorption of calcium The effect of protein and of certain drugs on calcium metabolism Is also described ... 

In extensive studies of the effect of fluoride In patients with osteoporosis carried out In this Research Unit, a therapeutic dally dose of 45 mg fluoride per day was used as sodium fluoride. The main effect of fluoride on calcium metabolism was a decrease of the urinary calcium, while the fecal calcium did not change and the calcium balance also remained unchanged. Also, the Intestinal absorption of calcium remained unchanged during the high fluoride Intake (Table I), The decrease In urinary calcium, Induced by sodium fluoride, may be due to decreased bone resorption, a very desirable effect for patients with osteoporosis. 

Elsair, J., R. Merad, R. Denine, M. Reggabi, B. Alamir, S. Benah, M. Azzouz, and K. Khelfat. 1980b. Boron as a preventive antidote in acute and subacute fluoride intoxication in rabbits its action on fluoride and calcium-phosphorus metabolism. Fluoride 13 129-138. 

Spencer H, Kramer L, Norris C, et al. 1980. Effect of aluminum on fluoride and calcium metabolism in man. Trace Subst Environ Health 14 94-102. 

Fluoride interferes with the metabolism of cells and enzymes. It is a cross-linking agent and rarely occurs in an elemental state in nature. It is a metabolic inhibitor, interfering with calcium metabolism and electron... 

The dark side of hydrofluoric acid is its toxicity and corrosiveness. Aqueous and anhydrous HF readily penetrate the skin, and, because of its locally anesthetizing effect, even in very small quantities can cause deep lesions and necroses [4, 5]. An additional health hazard is the systemic toxicity of fluoride ions, which interfere strongly with calcium metabolism. Resorption of HF by skin contact (from a contact area exceeding 160 cm ), inhalation, or ingestion leads to hypocalcemia with very serious consequences, for example cardiac arrhythmia. 

Based on limited epidemiologic evidence, fluoride supplements, with or without calcium, estrogen and vitamin D, are used by clinicians for the treatment of osteoporosis. However, knowledge of the effects of fluoride on calcium and phosphorus metabolism in normal animals is limited although Spencer et al. (32) reported that ingestion of fluoride by three osteoporotic men did not affect calcium absorption but caused a decrease in urinary excretion. Moreover, there is a need to determine the long-term effects of fluoride treatment on bone strength and on soft tissues ( ). 

Another experimental attempt to reverse osteoporosis was supervised by Khashayar Sakhaee, M.D., professor of internal medicine at the Center for Mineral Metabolism at the University of Texas, Southwestern Medical Center at Dallas, Texas, who tested a. slow-release fluoride in the amount of 25 milligrams together with 800 milligrams of calcium citrate twice daily on 980 volunteer elderly subjects with osteoporosis.The results of the three-year experiment were very encouraging. Dr. Sakhaee reported an average gain in spinal bone density of 5 percent per year every year for the three years of the experiment. 

The most important manifestation of hyperfluoric status is dental and skeletal fluorosis. In regions of volcanic activity, and in some arid zones and areas where phosphorites and apatites are mined and processed, agricultural animals and population often suffer from endemic and civilization-related fluorosis that mostly affects the teeth and skeleton. There arises the problem of reproduction and maintenance of dairy cattle (Ermakov etal. 1998, Ermakov 2001). In toxic quantities, fluorides impair the metabolism of calcium and synthesis of bone collagen by stimulating bone accretion, and speed up bone resorption and total calcium turnover in the body (Susheela and Mukher-jee 1981). 

A. In addition to Its direct cytotoxic and metabolic effects, fluoride binds avidly to calcium and magnesium causing hypocalcemia and hypomagnesemia. Fluoride disrupts many intracellular mechanisms including glycolysis, G-protein-mediated signaling, oxidative phosphorylation, ATP production, function of Na/K-ATPase, and potassium channels. 

Colonization of an early lesion by acidogenic organisms such as 5. mutans can prevent effective remineralization by lowering the local pH to such an extent that calcium phosphate precipitation will no longer occur. As well as catalysing remineralization fluoride ions act as inhibitors of bacterial metabolism and the effect of fluoride on acid production by S. mutans has been studied in some detail (see below). 

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