Abstract
Phospholipases (PLA’s) participate in the regulation of physiological and pathological processes in the cell, including the release of pro-inflammatory mediators and stimulation of inflammatory processes. It is also well known that fluoride can increase the inflammatory reactions. Therefore we decided to examine the effect of fluorides in concentrations determined in human serum on cPLA(2) and sPLA(2) activity. The incubation of macrophages in fluoride solutions significantly increased the amount of synthesized cellular cAMP, intracellular calcium and sPLA(2) activity in a dose-dependent pattern. The cPLA(2) activity, estimated by the amount of released arachidonic acid, increased significantly when 10 ?M NaF was used. The results of our study suggest that fluoride may change the activity of phospholipases in macrophage cells. Probably, increased cAMP concentration activates protein kinase C (PKC) and thus stimulates PLA(2). cAMP also regulates the passage of Ca(2+) through ion channels, which additionally influence PLA(2) throughout Ca(2+)-calmodulin dependent protein kinase.
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Influence of lithium and fluoride on degranulation from human neutrophils in vitro
We have demonstrated that degranulation from normal human neutrophils in whole blood was stimulated by low concentrations of lithium salts and was produced by noncytolytic means. Significant amounts of beta-glucuronidase could be released from the primary granules, in addition to vitamin B12- binding protein from the secondary granules, by 10
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Stimulation of cAMP accumulation and superoxide production in human neutrophils and monocytes
The effect of sodium fluoride (NaF) on superoxide generation and cyclic adenosine monophosphate (cAMP) levels in human neutrophils and monocytes was investigated. NaF (greater than 10 mM) stimulated superoxide (O2-) production in both cell types in a time dependent manner. NaF (0.5 to 20 mM) increased cAMP levels by 1.5-
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Sodium fluoride evoked histamine release from mast cells. A study of cyclic AMP levels and effects of catecholamines
Calcium triggers the secretion of histamine from mast cells after previous exposure to sodium fluoride. The secretory process can be divided into a fluoride-activation step and a calcium-induced secretory step. It was observed that the fluoride-activation step is accompanied by an elevation of cAMP levels within the cells. The attained
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Stimulation of cAMP accumulation in rat aorta and diaphragm by fluorine containing compounds
Evidence is presented that accumulation of cAMP in isolated rat thoracic aorta and diaphragm is stimulated by several fluorine containing compounds (NaF, Na2PO3F (MFP) and SnF2). Time course experiments with NaF showed that maximal stimulation of cAMP accumulation was observed within 2.5 min. NaF and MFP produced significant increases in
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Some characteristics of fluoride-induced cell death in rat thymocytes: cytotoxicity of sodium fluoride
Fluoride is found in the atmosphere, water, soil, coal, food, dental and industrial uses. There were some case reports concerning acute fluoride poisoning in workplaces and laboratories. However, there is limited information concerning the mechanism of fluoride-induced cell death. To study the cytotoxicity of fluoride, the effect of sodium fluoride
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Does Fluoride Ingestion Affect Developing Immune System Cells?
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Fluoride & the Immune System - Summation from the US National Research Council (2006)
“There is no question that fluoride can affect the cells involved in providing immune responses. The question is what proportion, if any, of the population consuming drinking water containing fluoride at 4.0 mg/L on a regular basis will have their immune systems compromised? Not a single epidemiologic study has investigated whether fluoride in the drinking water at 4 mg/L is associated with changes in immune function. Nor has any study examined whether a person with an immunodeficiency disease can tolerate fluoride ingestion from drinking water.”
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Is the Ingestion of Fluoride an Immunosuppressive Practice?
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