Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of magnesium deficiency on bone cell differentiation and bone formation was investigated using in vivo matrix-induced endochondral ossification as a test system. Demineralized bone matrix was implanted subcutaneously in young (35-day-old) male Long-Evans rats that had been fed a semisynthetic Mg-deficient diet (50 ppm Mg) for 7 days. Plasma Mg levels were reduced to 25-30% of control values at that time. Control rats were paired the same diet, supplemented to contain 1000 ppm Mg. The implants were harvested 7, 9, 11, 15, and 20 days after implantation and analyzed for Mg and Ca content, 45Ca incorporation, and alkaline phosphatase levels. At each stage, plaques (implants) removed from Mg-deficient rats showed retardation in cartilage and bone differentiation and matrix calcification. Magnesium content was markedly reduced when compared to the control plaques. Histological appearance of the matrix-induced plaques confirmed the retardation in bone development and mineralization suggested by the chemical indicators. Most marked was the virtual absence of bone marrow in 20-day-old plaques in Mg-depleted rats. These data show that bone cell differentiation can occur in a severely Mg-depleted environment, although the onset of mineralization and bone remodeling was delayed and bone marrow differentiation was impaired.
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PMID:Influence of magnesium depletion on matrix-induced endochondral bone formation. 11 39

The effect of magnesium deficiency on phosphatase activity and bone composition was determined in the femora of young rats. In the right distal metaphysis the acid and alkaline phosphatase activities were decreased in magnesium-deficient rats, and the activity of bone alkaline phosphatase in the incubation mixture after adding magnesium was significantly greater in the magnesium-deficient than in the control rats. In the left distal metaphysis the water content was significantly lower in the magnesium-deficient rats at the fifth week but not at the third week. Conversely, the ash content of metaphyseal bone was significantly increased in magnesium-deficient rats at the fifth week, but not at the third week. The magnesium and phosphorus contents were abnormally low in the deficient bone at both periods. The calcium content was increased in the deficient bone at the third week, but not at the fifth week.
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PMID:Bone composition and phosphatase activity in magnesium deficiency in rats. 114 Dec 63

Chronic administration of cadmium chloride to rats (13.3 mumol/kg body wt per dose subcutaneously) produced a decrease in the activity of alkaline phosphatase in the intestinal mucosa to less than half that in control rats by the time cumulative doses of between 30 and 48 mumol had been administered. The reduced level of activity remained approximately steady following further dosing. Three isoenzymes of intestinal alkaline phosphatase were separated electrophoretically. Chronic cadmium treatment markedly decreased the proportion of the 2 isoenzymes with lower electrophoretic mobility. Some analogies are drawn between the effect of cadmium administration, and magnesium deficiency on changes in intestinal alkaline phosphatase.
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PMID:The effect of chronic parenteral administration of cadmium on isoenzyme levels of alkaline phosphate in intestinal mucosa. 272 9

The causes for low serum alkaline phosphatase (ALP) activity (reference range 30-115 U/L) in a large Veterans Medical Center were reviewed. Of 69,864 ALP determinations made over a 4-year period, 130 were low (< 30 U/L, 0.19%), representing 88 individual patients. Of these, 83 (primarily men, 96%) patients' charts were reviewed and classified into two groups, those with and those without conditions previously reported to be associated with decreased serum ALP activity: 47% had conditions associated with low ALP activity, the most frequent being cardiac surgery and cardiopulmonary bypass (26.5%), malnutrition (12.0%), magnesium deficiency (4.8%), hypothyroidism (2.4%), and severe anemia (1.2%); 53% of patients did not have clinical conditions previously associated with low ALP activity. No case of clinically apparent hypophosphatasia, for which low ALP activity is the defining characteristic, was found in this population of veterans. A low serum ALP may be of significance in other patient populations such as children, where it is associated with achondroplasia and cretinism, or in postmenopausal women with osteoporosis taking estrogen replacement therapy. In the predominantly adult male population in this study, low ALP activity was rare; it was seen most frequently in cardiac surgery patients postoperatively, a clinical condition heretofore not commonly associated with low serum ALP activity.
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PMID:Significance of low serum alkaline phosphatase activity in a predominantly adult male population. 772 Feb 39

To examine the contribution of exogenous calcium and oxalate in magnesium deficiency, intestinal absorption of both calcium and oxalate was studied by preparing brush border membrane vesicles (BBMV). Purity of the BBMV was ascertained biochemically by enrichment of the marker enzyme alkaline phosphatase by 14-fold with a concomitant 90 per cent decrease in the basolateral marker enzyme Na+/K(+)-ATPase in the purified membrane preparation as compared to the respective homogenate in both the groups. Uptake studies were carried out by a rapid filtration technique. The kinetics were studied by measuring the rate of influx as a function of concentration (0.1-1.0 mM). BBMV from both the groups showed a linear positive relationship between the uptake rate and the concentration for both calcium and oxalate, thereby demonstrating that calcium and oxalate are transported through intestinal microvillus membrane by a simple passive diffusion process. However, the rate of uptake of calcium and oxalate was significantly higher in the magnesium-deficient group as compared to the pair-fed control group, as shown by the increase in the slope line for both calcium and oxalate (for calcium, control = 3.88, deficient = 5.86; for oxalate, control = 4.41, deficient = 7.20). Analysis of the lipid composition of the BBM revealed a significant decrease in the cholesterol content (P < 0.01) with a concomitant increase in the triglycerides (P < 0.01) and total fatty acid content (P < 0.001) in the magnesium-deficient group. Thus the results indicate that, although the mechanism of translocation of calcium and oxalate in the intestine is similar in the two groups, magnesium deficiency leads to hyperabsorption of both the ligands through alterations in the lipid composition of the membrane, thereby increasing the risk of stone formation.
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PMID:Intestinal absorption of calcium and oxalate in magnesium-deficient rats. 839 6

Prospects of using different alkaline phosphatases bearing zinc and magnesium ions in their catalytic and allosteric sites, respectively, in pharmaceutical and clinical analysis were demonstrated. Also their application for the determination of zinc in insulin to control injection quality and magnesium in human urine for the diagnosis and treatment of magnesium deficiency was shown. The reaction of p-nitrophenyl phosphate hydrolysis was chosen as an indicator. The choice of appropriate alkaline phosphatase was substantiated, the influence of the nature of buffer solutions on the behavior of the enzyme-metal systems was studied, and the conditions of the indicator reaction proceeding in the presence of sample matrixes were optimized. Simple, rapid, sensitive, and selective enzymatic procedures for determining zinc and magnesium based on their inhibiting and activating effects on the catalytic activity of alkaline phosphatases from seal and chicken intestine, respectively, were developed.
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PMID:Application of alkaline phosphatases from different sources in pharmaceutical and clinical analysis for the determination of their cofactors; zinc and magnesium ions. 1737 82