Serum Bone Alkaline Phosphatase Activity Research Articles

Comparison between the effects of older versus newer generations of antiepileptic drugs on bone metabolism in adult Iraqi patients: an observational study

Background: Metabolic bone disorder is a significant endocrine system disorder that encompasses any disorder that alters the natural skeleton's mineralization process. Epilepsy is a prevalent central nervous system disorder that can cause biochemical abnormalities involving bone metabolism in the epileptic patients. The present study aimed to investigate the effects of chronic use of older compared to the newer generations of antiepileptic drugs on bone metabolism-related biomarkers. Methods: The study included fifty-one epileptic outpatients who attended the Consultation Clinic of Baghdad Teaching Hospital at the Medical City Complex from October/2021 to December/2021. The selected patients were on antiepileptic drugs for more than 2 years, hence were grouped according to their antiepileptic therapy into: Group-1: 24 epileptic patients on old antiepileptic drugs (Carbamazepine or Valproate). Group-2: 27 epileptic patients on new antiepileptic drugs (Levetiracetam), compared with Group-3: 28 healthy control subjects. Serum was obtained from their blood specimens to measure: calcium and inorganic phosphate by colorimetric assays, parathyroid hormone, and level of bone alkaline phosphatase activity. Results: Data analysis revealed that the median value of serum parathyroid hormone levels was significantly elevated in the epileptic patients' groups compared to the healthy control group. However, group-2 (new generation antiepileptic drugs) presented higher values. Whereas serum calcium and inorganic phosphate levels showed non-significant variation for all the studied groups. Furthermore, serum bone alkaline phosphatase activity exhibited significantly higher values in the patients compared to the healthy subjects group, with more significant elevation among those on old generation antiepileptic drugs (Carbamazepine or Valproate). Conclusion: Epileptic individuals who had been on AEDs for more than two years had increased parathyroid hormone levels, which were boosted by the newer antiepileptic drug Levetiracetam. Furthermore, BAP serum levels were considerably greater in epileptic patients than in healthy control participants, with larger values generated by older antiepileptic medications.

Oxidative and Antioxidative Status Expressed as OSI Index and GSH/GSSG Ratio in Children with Bone Tumors after Anticancer Therapy Completion.

Aims. There are no data on the redox status of children with bone tumors in complete disease remission. Therefore, the presented study examined the reduced/oxidized glutathione (GSH/GSSG) ratio, total oxidant capacity (TOC) and total antioxidant capacity (TAC) values as well as the oxidative stress index (OSI) for assessing alterations in the oxidant/antioxidant balance in 35 children with osteosarcoma or Ewing’s sarcoma after anticancer therapy completion (median 14 months) compared with a control group. Methods. GSH, GSSG, TOC, TAC concentrations and bone alkaline phosphatase (BALP) activity were evaluated by immunoenzymatic (ELISA) and enzymatic methods. Results. We found no differences in serum BALP activity between all survivors with bone tumors and the control group. Patients with osteosarcoma after anticancer therapy completion had significantly higher values of TAC, GSH and the GSH/GSSG ratio as well as GSSG than healthy subjects. In patients with Ewing’s sarcoma, we found significantly higher values of TOC concentration compared with healthy children. In addition, survivors with Ewing’s sarcoma had higher TOC concentrations and OSI index values (p < 0.01), but a lower GSH/GSSG ratio (p < 0.05) than survivors with osteosarcoma. A positive correlation between TOC and the post-therapy period was observed in survivors. Conclusions. We found that in survivors with bone tumors, a disturbed balance between prooxidants and antioxidants persists after the completion of anticancer treatment. Moreover, an increased TOC value together with the post-therapy period may suggest increasing oxidative processes in survivors with bone tumors after treatment. Further observations will allow assessment of the relationship between the oxidant/antioxidant status and the predisposition of survivors to bone neoplastic disease recurrence.

Evaluation of serum bone alkaline phosphatase activity in patients with liver disease: Comparison between electrophoresis and chemiluminescent enzyme immunoassay

BackgroundSerum bone alkaline phosphatase (ALP) is a marker of bone formation and metabolism. However, existing methods for measuring it have their limitations and their accuracy has not been determined. MethodsWe measured serum bone ALP activity in 127 patients with liver disease using 2 methods: electrophoresis and chemiluminescent enzyme immunoassay (CLEIA). The results of these 2 methods were compared and analyzed according to gender, age and several serum biochemical markers. ResultsWhen ALP3 (%; bone-type isozyme activity as a percentage of total ALP activity) values were high, the 2 methods showed good correlation. However, with a decrease in ALP3 (%) levels, the correlation coefficient (R) also decreased. Starting with ALP3 (%)<23, R values markedly decreased to <0.50 (p>0.05). Five outliers displayed low ALP3 (%) activity levels. Furthermore, in regard to genders, there were significant differences in total cholesterol (TC), γ-glutamyltransferase (γ-GTP), ALP and ALP3 (%) levels (p<0.05). ConclusionsWhen serum ALP3 (%) levels were high in patients with liver disease, the accuracy of electrophoresis was comparable to that of CLEIA. However, the accuracy of electrophoresis needs to be evaluated with further when patient samples under certain conditions.

Moderate Strontium Loading Induces Rickets in Rats with Mild Chronic Renal Failure

Background/Aims: Renal osteodystrophy and eventually osteoporosis are serious long-term complications in children with end-stage renal disease before and after renal transplantation. Strontium (Sr) salts are used for treatment of osteoporosis in adults. Methods: To evaluate the time-dependent effects of Sr on growth plate morphology and their reversibility, chronic renal failure (CRF) rats received either normal or Sr-loaded drinking water (2 g/l; ±200 mg/kg/day) for periods of 2, 6 and 12 weeks with or without subsequent washout periods of 0, 2, 4 or 8 weeks. Results: While weight gain was not affected by Sr loading, a significant enlargement of the entire growth plate, mainly due to expansion of the hypertrophic zone, was already present after 2 weeks. Sr-loaded animals showed increased osteoid areas and reduced bone formation rates at 2, 6 and 12 weeks compared to controls. This was accompanied by reduced PTH levels and increased serum bone alkaline phosphatase activity. After the washout periods these effects were reversed. In general, the height of the hypertrophic zone was positively correlated with osteoid area and negatively correlated with bone formation rate. Conclusion: Moderate Sr loading in CRF rats results in rapid development of rickets, which is reversible after washout.

Melatonin effect on bone metabolism in rats treated with methylprednisolone

The present study was undertaken to examine the effect of melatonin (25 microg/mL of drinking water, about 500 microg/day) on a 10-wk long treatment of male rats with methylprednisolone (5 mg/kg s.c., 5 days/wk). Bone densitometry and mechanical properties, calcemia, phosphatemia and serum bone alkaline phosphatase activity and C-telopeptide fragments of collagen type I (CTX) were measured. Both melatonin and methylprednisolone decreased significantly body weight (BW) and the combination of both treatments resulted in the lowest BW values found. Consequently, all results were analyzed with BW as a covariate. Densitometrically, methylprednisolone augmented bone mineral content (BMC), bone area (BA) and bone mineral density (BMD) in the entire skeleton, BMC in cortical bone, and BMC and BMD in trabecular bone. Melatonin increased BMC and BA in whole skeleton and BMC and BMD in trabecular bone. For BMC and BA of whole skeleton, BMC of cortical bone, and BMC and BMD of trabecular bone, the combination of glucocorticoids and melatonin resulted in the highest values observed. Femoral weight of rats receiving methylprednisolone or melatonin increased significantly and both treatments summated to achieve the greatest effect. In femoral biomechanical testing, methylprednisolone augmented ultimate load and work to failure significantly. Rats receiving the combined treatment of methylprednisolone and melatonin showed the highest values of work to failure. The circulating levels of CTX, an index of bone resorption, decreased after methylprednisolone or melatonin, both treatments summating to achieve the lowest CTX values found. Serum calcium increased after methylprednisolone and serum phosphorus decreased after treatment with methylprednisolone or melatonin while serum bone alkaline phosphatase levels remained unchanged. The results are compatible with the view that low doses of methylprednisolone or melatonin decrease bone resorption and have a bone-protecting effect.

Melatonin effect on bone metabolism in rats treated with methylprednisolone

The present study was undertaken to examine the effect of melatonin (25 microg/mL of drinking water, about 500 microg/day) on a 10-wk long treatment of male rats with methylprednisolone (5 mg/kg s.c., 5 days/wk). Bone densitometry and mechanical properties, calcemia, phosphatemia and serum bone alkaline phosphatase activity and C-telopeptide fragments of collagen type I (CTX) were measured. Both melatonin and methylprednisolone decreased significantly body weight (BW) and the combination of both treatments resulted in the lowest BW values found. Consequently, all results were analyzed with BW as a covariate. Densitometrically, methylprednisolone augmented bone mineral content (BMC), bone area (BA) and bone mineral density (BMD) in the entire skeleton, BMC in cortical bone, and BMC and BMD in trabecular bone. Melatonin increased BMC and BA in whole skeleton and BMC and BMD in trabecular bone. For BMC and BA of whole skeleton, BMC of cortical bone, and BMC and BMD of trabecular bone, the combination of glucocorticoids and melatonin resulted in the highest values observed. Femoral weight of rats receiving methylprednisolone or melatonin increased significantly and both treatments summated to achieve the greatest effect. In femoral biomechanical testing, methylprednisolone augmented ultimate load and work to failure significantly. Rats receiving the combined treatment of methylprednisolone and melatonin showed the highest values of work to failure. The circulating levels of CTX, an index of bone resorption, decreased after methylprednisolone or melatonin, both treatments summating to achieve the lowest CTX values found. Serum calcium increased after methylprednisolone and serum phosphorus decreased after treatment with methylprednisolone or melatonin while serum bone alkaline phosphatase levels remained unchanged. The results are compatible with the view that low doses of methylprednisolone or melatonin decrease bone resorption and have a bone-protecting effect.

Hepatitis C-associated osteosclerosis (HCAO): report of a new case with involvement of the OPG/RANKL system

We report a new case of hepatitis C-associated osteosclerosis (HCAO). The clinical presentation of the patient was an acquired deep severe bone pain with increased serum bone alkaline phosphatase activity (up to 12 times the upper limit of normal), and generalized bone sclerosis, temporally related to the hepatitis C-virus (HCV) infection. We documented in this patient an increase of circulating osteoprotegerin (OPG), and a concentration of circulating receptor activator for nuclear factor-kB ligand (RANKL) below the lower limit of the reference range. The observed abnormalities of the OPG/RANKL system may contribute to the maintenance of the positive balance of bone remodeling that characterizes patients with HCAO.

Melatonin increases oestradiol‐induced bone formation in ovariectomized rats

To assess the effect of melatonin on bone metabolism in ovariectomized rats, receiving oestradiol therapy or not, melatonin was administered in the drinking water (25 microg/mL water) and oestradiol (10 microg/kg body weight) or vehicle was given subcutaneously 5 days/week for up to 60 days after surgery. Urinary deoxypyridinoline (a marker of bone resorption) and circulating levels of bone alkaline phosphatase activity (a marker of bone formation), as well as serum calcium and phosphorus levels, were measured every 15 days. Bone area (BA), bone mineral content (BMC), bone mineral density (BMD) and total body fat (expressed as 100 g body weight) were measured by dual-energy X-ray absorptiometry at the end of the experiment. Body weight and total body fat were augmented after ovariectomy, and decreased after melatonin or oestradiol treatment. The effect of melatonin on body weight was seen in sham-operated rats only. Ovariectomy augmented, and melatonin or oestradiol lowered, urinary deoxypyridinoline excretion. This effect of melatonin and oestradiol was seen mainly in ovariectomized rats. The efficacy of oestradiol to counteract ovariectomy-induced bone resorption was increased by melatonin. Melatonin or oestradiol lowered serum bone alkaline phosphatase activity. Melatonin inhibition was seen mainly on the increase of bone alkaline phosphatase activity that followed ovariectomy. Serum phosphorus levels decreased after melatonin administration and were augmented after oestradiol injection; overall, melatonin impaired the increase of serum phosphorus caused by oestradiol. Ovariectomy decreased, and oestradiol increased, serum calcium levels while melatonin augmented serum calcium in sham-operated rats only. On day 60 after surgery, BMD and content decreased after ovariectomy and were increased after oestradiol injection. Melatonin augmented BA of spine and BMC of whole of the skeleton and tibia. The highest values observed were those of rats treated concurrently with oestradiol and melatonin. The present results indicate that: (i) melatonin treatment restrained bone remodelling after ovariectomy; (ii) the effect of melatonin required adequate concentrations of oestradiol; (iii) melatonin augmented oestradiol effects on bone in ovariectomized rats; (iv) a counter-regulation by melatonin of the increase in body fat caused by ovariectomy was uncovered. The melatonin doses employed were pharmacological in terms of circulating melatonin levels but not necessarily for some other fluids or tissues.

Different distributions of human bone alkaline phosphatase isoforms in serum and bone tissue extracts

Background: In vitro, bone alkaline phosphatase (BALP) is released from the osteoblast membrane with its glycosylphosphatidylinositol (GPI) anchor still attached (i.e., in an anchor-intact form); however, in vivo, BALP circulates as a variable mixture of anchorless isoforms, which can be identified by high-performance liquid chromatography (HPLC). Previous studies have shown that the relative abundance of these BALP isoforms in serum may be clinically useful for the diagnosis and management of metabolic bone disease. Methods: In the current studies, we describe a method for the determination of anchorless BALP isoforms in extracts of bone and we present novel data on the conversion of anchor-intact to anchorless BALP by incubation with endogenous circulating GPI-specific phospholipase D (GPI-PLD). Results: A 72-h extraction with 0.1% Triton X-100 released approximately 90% of the BALP activity from powdered bone. An average of 19% of this activity was anchorless, but essentially all of the activity could be converted to the anchorless form by incubation with partially purified GPI-PLD from human serum. Using HPLC, we detected four BALP isoforms (B/I, B1x, B1, and B2) in these GPI-PLD-treated extracts of bone. An additional BALP fraction was also detected in the samples during the initial phase of GPI-PLD treatment. Conclusions: The abundance of the BALP isoforms differed between bone and serum, particularly for the B/I isoform, which comprised, on average, 18% of the BALP in GPI-PLD-treated extracts of healthy bone tissue, but only 6% of the total BALP activity in serum from healthy individuals. Based on our recent finding of differences in the number of sialic acid residues between the BALP isoforms, we hypothesize that this difference between BALP isoforms in serum and extracts of bone is due to the different patterns of glycosylation, which results in different biological half-lives in the circulation. A preliminary application of our method to the extraction of BALP isoforms from a small number of human bone samples suggests that the method should be useful for studies of human skeletal site-specific and metabolic bone disease-specific differences in the amounts and distributions of the BALP isoforms in bone.

Semiautomated analysis of alkaline phosphatase isoenzymes in serum of normal cynomolgus monkeys (Macaca fascicularis).

Alkaline phosphatase (ALP) isoenzyme analysis, using a combination of wheat germ lectin (WGL) precipitation, levamisole inhibition and an automated p-nitrophenylphosphate assay was validated for use with serum from monkeys (Macaca fascicularis) and used to determine the activities of liver ALP (LALP), bone ALP (BALP) and intestinal ALP (IALP). Based on serial dilution studies and within-run and between-run coefficients of variation, each assay had excellent linearity and acceptable precision. In addition, liver and intestinal mucosa extracts for tissue specific alkaline phosphatases were used to confirm assay validations. Gender-specific differences for total ALP, LALP, and BALP activities were present in sera from normal monkeys between 2 and 4 years of age. Males had 1.3-fold higher total ALP and LALP activities, and 1.5-fold higher BALP activity compared with females. The majority of ALP activity in normal monkey serum was LALP isoenzyme activity, which ranged from 56.7% to 94.7% of total activity. Serum BALP activity ranged from 5.3% to 42.8%. There was negligible IALP activity in all serum samples.

Modulation of bone mass and turnover in growing rats by voluntary weight-bearing exercise and glucose supplementation.

Female Sprague-Dawley rats, 9 weeks of age, were assigned to four groups: Group 0 (n = 8) was dissected for base-line control, and the other three groups were fed for 3 mo: Group 1 (n = 9), sedentary controls; Group 2 (n = 6), running rats housed in a cage with a treadmill and pair-fed with Group 1; and Group 3 (n = 7), running rats, pair-fed and allowed free access to additional glucose. The distances of voluntary running did not significantly differ between Groups 2 and 3. Menstrual cycles in these rats were apparently maintained as observed from daily running distances. The amount of glucose taken by rats in Group 3 was 3.5 +/- 0.4 (mean and SE) g/d. Body weight (BW) at the end of the experiment for Groups 1, 2, and 3 were 295.0 +/- 7.9, 211.7 +/- 5.4 (p < 0.001 vs. Group 1), and 259.0 +/- 3.5 g (p < 0.01 vs. Group 2), respectively. The parameters of bone mass such as ash weights of the femur and bone mineral content of the lumbar spine and the tibia in Groups 1 and 2 did not differ, but the values were significantly greater in Group 3 than in Group 2. However, these parameter values corrected for BW were significantly greater in Group 2 than in Group 1 and did not significantly differ between Groups 2 and 3. The parameters of bone formation, such as serum bone alkaline phosphatase activity levels and trabecular bone formation rates corrected for BW, were significantly greater in Group 2 than in Group 1 but did not differ between Group 2 and 3. However, the parameters of bone resorption, such as serum tartrate resistant acid-phosphatase levels, were significantly less in Group 3 than in Group 2. These results suggest that voluntary running augments the age-dependent increase in bone mass by modulating the bone turnover when an adequate energy source is supplied under conditions of normal menstruation, and an adequate supply of energy could be necessary to enhance the age-dependent increase in bone mass.

Assessment of serum bone alkaline phosphatase activity with a new elisa using a specific monoclonal antibody

Assessment of serum bone alkaline phosphatase activity with a new elisa using a specific monoclonal antibody

Posttranslational heterogeneity of bone alkaline phosphatase in metabolic bone disease.

Bone alkaline phosphatase is a marker of osteoblast activity. In order to study the posttranscriptional modification (glycosylation) of bone alkaline phosphatase in bone disease, we investigated the relationship between mass and catalytic activity of bone alkaline phosphatase in patients with osteoporosis and hyperthyroidism. Serum bone alkaline phosphatase activity was measured after lectin precipitation using the Iso-ALP test kit. Mass concentration of bone alkaline phosphatase was determined with an immunoradiometric assay (Tandem-R Ostase). In general, serum bone alkaline phosphatase mass and activity concentration correlated well. The activity : mass ratio of bone alkaline phosphatase was low in hyperthyroidism. Activation energy of the reaction catalysed by bone alkaline phosphatase was high in osteoporosis and in hyperthyroidism. Experiments with neuraminidase digestion further demonstrated that the thermodynamic heterogeneity of bone alkaline phosphatase can be explained by a different glycosylation of the enzyme.

Isoenzymes of alkaline phosphatase in epileptic patients receiving carbamazepine monotherapy.

The effects of carbamazepine monotherapy were investigated in 20 female and 21 male epileptic patients to determine whether treatment would induce an increase in serum alkaline phosphatase (ALP) activity, a known effect of many anticonvulsant drugs. Serum total ALP activity was increased in nine out of the 41 patients (22%), serum bone ALP activity was increased in 10 (24%), and serum non-bone ALP activity was increased in three (7%). There was no significant difference when the mean of the patients' serum total ALP was compared with that of the controls. Twenty per cent of the patients with increased serum bone ALP had normal serum total ALP, indicating that increased serum bone isoenzyme activity may precede an increase in the total enzyme activity. This should be considered when interpreting results of increased total ALP in epileptic patients.

Time-dependent changes in bone, placental, intestinal, and hepatic alkaline phosphatase activities in serum during human pregnancy.

To measure changes in bone alkaline phosphatase (EC 3.1.3.1) activity in serum as a function of duration of pregnancy, we adapted our existing alkaline phosphatase (ALP) isoenzyme assay (which has been used to measure bone, hepatic, and intestinal ALP activities in serum, in the absence of placental ALP) to allow quantification of individual ALP isoenzyme activities in the presence of placental ALP. The resulting CV for repeat measurements of bone ALP activity in artificial isoenzyme mixtures ranged from 23% for samples in which the bone isoenzyme represented 7% of total ALP activity to 11% for samples in which bone ALP accounted for 48% of total ALP activity. Values for repeat determinations of bone ALP activity in human serum samples (i.e., including samples obtained from pregnant women and from nonpregnant controls) varied by an average of 18%. We find, in initial applications of this method, that (a) the amount of bone ALP activity in serum is increased during pregnancy (P less than .001), and remains increased at six weeks postpartum, in non-lactating women (P less than .001), and (b) bone ALP activity at term was not significantly different in pregnant women with pre-eclampsia, diabetes, premature rupture of membranes, or premature labor, compared with normal pregnancies at term. Our data support the hypothesis that maternal bone formation may be increased during pregnancy.