Alkaline Phosphatase Isoenzymes Research Articles

Infantile Hypophosphatasia: Clinical Case

Background . Hypophosphatasia is rare hereditary disease caused by deficiency of the tissue-nonspecific alkaline phosphatase isozyme. It manifests with bone and teeth mineralisation defects, electrolyte imbalance, respiratory disorders, convulsive syndrome, physical developmental delay, nephrocalcinosis. The rarity of this disease, clinical polymorphism, non-specificity of complains and signs are the major reasons of hypophosphatasia late diagnosis. The enzyme replacement therapy with recombinant alkaline phosphatase (asfotase alfa) can be used for treatment of severe forms of disease. Clinical Case Description . The girl (1 y 4 m) was routinely admitted with complains of physical developmental delay and psychomotor retardation, deformation of lower limbs, chest, gait abnormality, teeth loss and with diagnosis «protein-calorie malnutrition». Rickets-like changes in skeleton, myopathic syndrome, early normal teeth loss, hepatomegaly were revealed. Reduced activity of alkaline phosphatase in blood serum (33 u/l; reference range 156–369 u/l) was revealed. The infantile hypophosphatasia has been diagnosed. Due to molecular genetic testing of ALPL gene we revealed pathogenic variants c.526G>A (p.Ala176Thr) and c.1375G>A (p.Val459Met) in compound heterozygous state. The asphotase alpha therapy was initiated at the age of 1 y 10 m, the dose was 2 mg/kg subcutaneously 3 times a week. The results of 6 months of the therapy are the following: significant increase in the activity of alkaline phosphatase (maximum 4400 u/l), body weight (+ 2 kg), growth (+ 6 cm), reduction of bone deformation, normalisation of muscle tone and gait, exercise tolerance. The patient tolerated the drug administration well. Rarely there were hyperemia zones up to 4 cm in diameter with moderate induration at the injection site but they spontaneous disappeared in 2–3 days though. Conclusion. Patients with rickets-like diseases and low alkaline phosphatase activity requires performing of molecular genetic testing to confirm hypophosphatasia. Timely diagnosis and early initiation of enzyme replacement therapy can significantly improve the quality of life of children with hypophosphatasia.

Consecutive changes in serum alkaline phosphatase isoenzyme 3 activities in Holstein heifers during the first 18 months of life.

This study investigated consecutive fluctuations in serum activities of bone-specific alkaline phosphatase (ALP) isoenzyme 3 (ALP3) in 11 clinically healthy Holstein heifers during the first 18 months of life. ALP3 activities at the first sampling time point after weaning (3 months) were significantly lower than those at multiple time points during the pre-weaning period. Those activities increased from a minimum at 3 months to a peak at 6 months during the post-weaning period. In the anthropometric data, daily body weight and wither height gains appeared to be below the public data at 4 months and 4–5 months, respectively. The data suggested that serum ALP3 activity can be used to monitor skeletal growth of heifers at weaning.

Regression formula to predict the International Federation of Clinical Chemistry and Laboratory Medicine measure of alkaline phosphatase activity in canine blood based on the Japan Society of Clinical Chemistry reference method.

The Japan Society of Clinical Chemistry reference method (JSCC method) is used to measure alkaline phosphatase (ALP) activity only in Japan. Other countries use the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) reference method to measure ALP activity. Since April 2020, human medical institutions in Japan have been gradually switching to the IFCC method. However, it is unclear whether the supply of reagents required for the JSCC method will be steady in the future. Additionally, the comparison of the performances and accuracies of these two methods for measuring ALP values remains uncertain in several animal species. In this investigation, we measured canine ALP activity using both methods and developed a formula to interconvert the two resulting values. The regression formula for ALP values measured using the modified JSCC (x) and IFCC (y) methods was determined as log10 y=0.960 log10 x−0.395 (r=0.997). However, the correlation between values based on JSCC and IFCC methods can change depending on the composition of ALP isozymes. Therefore, the developed formula can currently serve as a provisional strategy in calculating ALP levels. Nevertheless, this formula might avoid confusion in the clinical field during the transition from the JSCC to the IFCC method when both measurement values co-exist.

Determination of plasma bone-specific alkaline phosphatase isoenzyme activity in Holstein calves using a commercial agarose gel electrophoresis kit.

We measured the bone-specific alkaline phosphatase (ALP) isoenzyme activity in 67 plasma samples from 14 newborn Holstein calves using both a conventional method (featuring heat inactivation) and a commercial agarose gel electrophoresis (AGE) kit; the relevant isoenzymes were termed bone-specific ALP (BAP) and ALP isoenzyme 3 (ALP3). We explored whether the AGE kit afforded reliable data when used to analyze samples from Holstein calves. The blood was collected from the jugular vein of each calf immediately prior to the first colostrum feeding (pre-feeding), 20 and 40 h after pre-feeding, and on days 4 and 7; whereas three samples (from three calves) were not obtained. The total plasma ALP activity varied widely, exceeding the ranges of reference values. On electrophoresis, 52 of 67 plasma samples (77.6 %) clearly contained both ALP isoenzyme 2 and ALP3, as did control human serum. The total ALP activity of the 52 samples ranged from 166-1989 U/L (median: 1013 U/L), whereas the values for the other 15 samples (22.4%) exhibiting abnormal isoenzyme fractionation ranged from 1014-5118 U/L (median: 1780 U/L). In the 52 plasma samples exhibiting clearly separated isoenzymes, ALP3 and BAP activities were strongly positively correlated as revealed by Deming regression (y = 0.93x + 22.6, p⟨0.0001) and Bland-Altman analysis (ALP3/BAP activities limit of agreement: -5.1%). Thus, the AGE kit yields useful information on newborn calves, and can replace the conventional method when the total plasma ALP activity is less than approximately 1000 U/L.

Comparison between bone alkaline phosphatase immunoassay and electrophoresis technique in hemodialysis patients.

Problem of the variability between the different methods using for bone alkaline phosphatase (bALP) determination greately influences the clinical significance of bALP as direct marker of bone metabolism. The aim of this study was to compare immunoassay with electrophoresis technique for bALP determination. We measured bALP in 71 patients on hemo - dialysis with agar gel electrophoresis (ISO-PAL, SEBIA) and immunoassay (OSTASE, Beckman Coulter). The analyzed methods showed significant correlation (Spearman's rho: 0.776, P < 0.01), but we found statistically significant (P < 0.01) positive bias (27%) for the results measured by immunoassay. In support of this, using electrophoresis technique we have detected presence of the intestinal isoenzymes of alkaline phosphatase in 55% of patients with median value of 30% of the total alkaline phoshatase and presence of liver-2 alkaline phosphatase isoform in 42% of patients with median value of 16.6%. The Kendall's W of 0.787 (P<0.0001) revealed significant concordance between two analysed methods. Cusum test showed no significant deviation from linearity (P=0.850). Despite good agreement between immuno - assay methods and electrophoresis technique for bALP determination, interchangeability between these two methods is questionable. Although immunoassays are increasingly used, as fully automated methods, in a large number of laboratories and become routine methods for bALP determination, it should be beared in mind, besides various interferences, also the heterogeneity of the bALP itself, especially in patients on hemodialysis.

2230 Benign Intermittent Intestinal Alkaline Phosphatase Elevation

INTRODUCTION: Liver function tests (LFTs) are commonly checked during routine clinical encounters without specific signs or symptoms. An elevated alkaline phosphatase (AP) level is followed by investigative algorithms to identify the etiology. Total AP comprises liver, bone and intestinal fractions. Elevated intestinal alkaline phosphatase (IAP) can occur as a rare benign condition or due to intestinal pathologies. Unlike previously published reports of benign persistent IAP elevation, our patient had intermittent elevation of IAP. CASE DESCRIPTION/METHODS: A 48-year-old obese female was seen in liver clinic for evaluation of elevated AP for the last two years. She had undergone work-up for elevated AP on several occasions but the exact etiology was not found. She did not report any prior history of jaundice, pruritis, nausea, vomiting, diarrhea, abdominal pain, arthralgias or arthritis. She denied any family history of elevated IAP. She was found to have elevated total AP on 6 separate occasions over the last 18 months ranging from 186 to 239 U/l (normal &lt; 117). Her fasting isozyme fractionation was checked 4 times. She had elevated total AP and normal liver/bone fractions on all occasions but twice had elevated IAP of 62 and 93 U/l (normal &lt; 15 U/l), 26-33% of total AP (normal &lt; 14%). Her other LFTs, TFT, PTH, Ca, CBC, BMP, GGT, viral hepatitis serologies, AMA and Vit D were unremarkable. Abdominal imaging revealed a fatty liver while a bone scan was normal. Our patient remained asymptomatic and did not require any treatment. DISCUSSION: Elevated AP can be physiological during rapid bone growth and pregnancy or pathological due to hepatobiliary disease or abnormal bone metabolism. Non-hepatic causes of elevated AP include heart failure, renal failure, hyperthyroidism, hyperparathyroidism and certain malignancies. IAP normally accounts for up to 14% of total AP. IAP can be elevated in conditions such as intestinal perforation, intestinal ischemia, extensive erosions/ulceration in GI tract, liver cirrhosis, familial benign elevation of IAP or post-prandial rise after a fatty meal particularly in patients with blood group B or O. Our patient did not have any of the above-listed conditions. Although she was blood group B, the blood draws were done after an overnight fast. While investigating elevated AP clinicians should be aware of pathological and benign causes of IAP elevation including benign intermittent IAP elevation which may require repeated testing of AP isozymes.

Design, synthesis and biological evaluation of trinary benzocoumarin-thiazoles-azomethines derivatives as effective and selective inhibitors of alkaline phosphatase

Design, synthesis and characterization of new trinary Benzocoumarin-Thiazoles-Azomethine derivatives having three bioactive scaffolds in a single structural unit were carried out. The newly synthesized molecules were investigated for the inhibitory activity on human tissue nonspecific alkaline phosphatase (h-TNAP) and human intestinal alkaline phosphatase (h-IAP) isozymes. All the tested compounds exhibited the potent inhibition profile on both isozymes of alkaline phosphatase i.e., h-TNAP and h-IAP. Molecular docking studies were performed to explore the putative binding mode of interactions of selective inhibitors. Moreover, the synthesized derivatives were evaluated against cervical cancer cell line, HeLa and a few compounds exhibited significant inhibition in the range of 21.0–69.7%. The derivatives can be potential and selective alkaline phosphatase inhibitors for future studies.

Serum alkaline phosphatase and γ-glutamyl transferase in acute pyelonephritis.

BackgroundElevated serum alkaline phosphatase (AP) and γ-glutamyl transferase (γ-GT) are commonly observed in patients with acute pyelonephritis. The goal of this study was to examine the clinical significance of elevated serum AP and γ-GT levels and to explore the mechanisms underlying these changes.MethodsWe examined serum AP and γ-GT levels in 438 patients with acute pyelonephritis. Urine AP/creatinine (Cr), urine γ-GT/Cr, fractional excretion of AP, and fractional excretion of γ-GT (FEγ-GT) were evaluated in patients with elevated and normal serum levels. AP isoenzymes were also examined.ResultsWe identified 77 patients (17.6%) with elevated serum AP and 134 patients (30.6%) with elevated serum γ-GT. Among them, both enzymes were elevated in 64 patients (14.6%). Older age, longer hospital stay, elevated baseline serum Cr, and complicated pyelonephritis were associated with increases in serum AP and γ-GT. Multivariate analysis showed that high serum AP levels were significantly correlated with renal impairment (odds ratio, 2.13; 95% confidence interval, 1.08–4.19; P = 0.029). FEγ-GT was significantly lower in patients with elevated serum enzyme levels. The liver fraction for AP isoenzyme profile did not increase in patients with elevated serum AP.ConclusionOur results demonstrated that elevated serum AP and γ-GT levels are associated with complicated pyelonephritis and renal impairment. Lower FEγ-GT levels in patients with elevated serum enzymes may be the result of decreased urinary excretion of these enzymes.

A novel combination of biallelic ALPL mutations associated with adult hypophosphatasia: A phenotype-genotype association and computational analysis study.

Hypophosphatasia (HPP) is an inherited metabolic disorder that causes defective skeletal and dental mineralization. HPP exhibits a markedly heterogeneous range of clinical manifestations caused by dysfunction of the tissue-nonspecific isozyme of alkaline phosphatase (TNSALP), resulting from loss-of-function mutations in the ALPL gene. HPP has been associated with predominantly missense mutations in ALPL, and a number of compound heterozygous genotypes have been identified. Here, we describe a case of a subject with adult-onset HPP caused by a novel combination of missense mutations p.Gly473Ser and p.Ala487Val, resulting in chronic musculoskeletal pain, myopathy, persistent fatigue, vomiting, and an uncommon dental phenotype of short-rooted permanent teeth. Pedigree and biochemical analysis indicated that severity of symptoms was correlated with levels of residual ALP activity, and co-segregated with the p.Gly473Ser missense mutation. Bioinformatic analysis to predict the structural and functional impact of each of the point mutations in the TNSALP molecule, and its potential contribution to the clinical symptoms, revealed that the affected Gly473 residue is localized in the homodimer interface and predicted to have a dominant negative effect. The affected Ala487 residue was predicted to bind to Tyr479, which is closely located the N-terminal α-helix of TNSALP monomer 2, suggesting that both changes may impair dimer stability and catalytic functions. In conclusion, these findings assist in defining genotype-phenotype associations for HPP, and further define specific sites within the TNSALP molecule potentially related to neuromuscular manifestations in adult HPP, allowing for a better understanding of HPP pathophysiology.

CHANGES IN THE BLOOD SERUM CONTENT OF BONE BIOMARKERS AND CYTOKINES IN CHILDREN WITH COMBINED TRAUMA

Twenty-nine children (mean age of 12.6 ± 2.3 years) with combined bone trauma were examined. The reference group consisted of 20 conditionally healthy children (mean age of 11.8 ± 2.7 years) without the pathology of the locomotor system. The content of bone biomarkers - osteoprotegerin (OPG), bone isoenzyme of alkaline phosphatase (AP), osteocalcin (OC), hyaluronic acid (HA), as well as matrix metalloproteinases (MMPs) and cytokines - TGF-β, MCP-1 and MIP-1β in serum was determined by the enzyme immunoassay in dynamics: on the 1-3rd, 7-th, 14-th and 30-th days after the trauma. Remodeling of bone tissue after a combined trauma at the stage of formation of the regenerate was established to be characterized by diverse changes in the serum content of bone biomarkers, which are not substantially dependent on the severity of the trauma. At the same time, a significant increase in the concentrations of OPG, AP and HA was combined with a pronounced decrease in the content of OC. At 7-14th days after the injury OC levels were lower by more than 3 times compared with the control, indicating a slowdown in the mineralization of the osteoid and a disturbance in the formation of bone tissue during this period. By 30 days after trauma serum concentrations of gelatinases (MMP-2, MMP-9) and collagenases (MMP-8) increased significantly, stromelysin levels (MMP-3) did not change. By 30th day after the injury serum concentrations of gelatinases (MMP-2, MMP-9) and collagenases (MMP-8) increased significantly, stromelysin levels (MMP-3) did not change, and the TIMP-1 content declined. Early detection of changes in blood levels of bone biomarkers during the process of the recovery after combined trauma in children makes it possible to ensure timely correction of disturbances and choice of optimal individual treatment tactics for the management of a particular patient, taking into account the peculiarities of his bone metabolism

MON-504 Osteomalacia During Pregnancy: Are Preventive Measures Enough to Avoid Future Fractures and Fetal Complications?

Title Osteomalacia during pregnancy; are preventive measures enough to prevent future fractures and fetal complications? Background We present a patient with a left hip fracture found to have FGF-23 induced osteomalacia whose clinical course was complicated by pregnancy. Clinical Case A 28 year old female with a history of iron deficiency anemia presented with left hip pain resulting in difficulty ambulating. Nine months prior, she had suffered a fall at home where she slid down nine steps on her left side, she developed pain in her left leg that prompted her to seek care in multiple emergency rooms; she was given acetaminophen for pain only. Seven months after the fall she started limping requiring a cane to ambulate, a week before admission, she had another mechanical fall where she slipped and fell landing again on her left hip after which she sought care. Further history revealed no regular intake of any medication including no inhaled or systemic steroids, regular menses and no symptoms of hyperthyroidism or malabsorption. Physical exam was pertinent for limited range of motion of her left leg. Blood tests were significant for alkaline phosphatase (ALP) 220 [30-95U/L], phosphorus 2.1 [2.5-5.0mg/dL], 25-OH vitamin D 14.80 [30-95pg/mL], Vitamin D 1,25(OH)2 <8 [18-72pg/mL], and Fibroblast Growth Factor 23 (FGF-23) 1241 [<180RU/ML]. Other labs included: Calcium 9.3 [8.2-10mg/dL], albumin 4.28 [3.5-5.70 g/dL], PTH 37.9 [15.0-65.0pg/mL], ALP isoenzymes: total ALP 202 [33-115 U/L], liver 44 [25-69%], bone 56 [28-66%], 24hr urine phosphorus 0.5 [0.3-1.3g/24hr] with under collected specimen , volume 1 liter and creatinine 0.9 [1-2 g/24hr], TSH 2.54 [0.35-4.70 uI/mL], cortisol after 1mg Dexamethasone was 0.3 [<1.8 mcg/dL]. The grossly elevated FGF-23 lead to a suspicion of tumor-induced osteomalacia, Imaging revealed stress fractures of the left aspect of the sacrum and left femoral neck. A bone scan was significant for diffuse lesions and bone densitometry showed osteoporosis in the lumbar region with a Z score of-2.5 and osteopenia of lumbar and femoral neck Z -1.9. Femoral neck biopsy was negative for malignancy. She underwent percutaneous pining of the femoral neck and was discharged with calcitriol, cholecalciferol and phosphate supplementation. An Octreotide scan obtained during follow-up was negative. Her phosphate levels have been difficult to manage even with high supplementation of phosphate, and further attempts to localize the tumor have been temporarily held as the patient is now pregnant. Conclusion This patient who initially presented with femoral neck and sacrum stress fractures and diagnosed with osteomalacia and hypophosphatemia allows us to learn and question what the appropriate treatment strategy should be to ensure both patient and fetus are adequately supplemented to prevent any future fractures in the mother and promote normal development of the fetus.

MON-494 Infantile Hypophosphatasia Diagnosed in Adulthood: A Case Report

Background: Hypophosphatasia (HPP) is a result of loss of function mutations within ALPL gene that encodes for the tissue-nonspecific isoenzyme of alkaline phosphatase (TNSALP). It is characterized by low serum alkaline phosphatase (ALP) activity. To date, HPP was recognized in 500-600 individuals in the United States. Clinical presentation and severity is broad, which can be explained by variable mutations in the TNSALP gene. Elevation of serum pyridoxal-5’-phosphate (vitamin B6), elevation of urinary of phosphoethanolamine (PEA) and finding of a mutation in the ALPL gene support the diagnosis. Asfotase alfa is a recombinant human alkaline phsosphatase that was approved in 2015 for treatment of patients, including adults, with pediatric-onset HPP. Case report: A 56 year old physician presented with a long history of low serum ALP on routine laboratory testing since childhood. During infancy he was diagnosed with craniosynostosis. He had delayed motor milestones and a waddling gait. He was never able to run as a child and he attended high school in a wheelchair. He had severe periodontal disease, lost his first tooth at age 4 and continued to lose his teeth despite excellent dental hygiene care. He has an extensive bone fractures history. He had his first fracture at the elbow at age 6 after he was pulled up by his hands. He developed metatarsal fractures around that time after a fall. He had a metacarpal fracture as an adult with bumping of his hand against the wall. At age 12 he developed hip pain and uveitis. He was diagnosed with ankylosing spondylitis (AS) at age 16 year with a positive HLA B 27. His most recent fracture was at age 45 after he slipped in the shower and sustained a hip fracture. At that time he had a BMD that showed osteoporosis. A bisphosphonate was offered but the patient refused medication as he was worried of the side effects. He has a family history of musculoskeletal disorders. His late mother had a history of low ALP, dental problems, metatarsal fractures and osteopenia. His sister has low ALP and had a low impact radial fracture. His sister’s son who is 18 years old was found to have low serum ALP and was found to have a Z score of -1.5 on BMD. When the patient presented to our clinic, his serum ALP was 22 U/L (n 40-115) and vitamin B 6 was 253 ng/ml (n 2.1-21.7). Genetic testing revealed heterozygous variant in the ALPL gene c.1251T>G (p.Asn417Lys). The patient’s sister and her son were found to have similar mutation of the ALPL gene. The patient was started on treatment with Asfotase alfa. After three months of treatment, the patient reported increased strength and reduced fatigue. Conclusion: We present a rare diagnosis of a 56 year old gentleman who was diagnosed with infantile HPP as an adult. The disease manifested as craniosynostosis, recurrent fractures and periodontal disease. He was started on Asfotase alfa with improvement of symptoms. .

Aptameric Probe Specifically Binding Protein Heterodimer Rather Than Monomers.

Dimerization of proteins occurs frequently and plays integral roles in biological processes. However, no single molecular probe is available for in situ detection of protein dimers on cells and tissues because of the difficulty of isolating complete protein dimers for probe preparation and screening, which has greatly hampered the biomedical study of protein dimers. Herein, a G‐rich DNA aptamer (termed BG2) that only binds alkaline phosphatase (AP) heterodimers rather than monomers is reported. This aptamer is generated by the cell‐SELEX (systematic evolution of ligands by exponential enrichment) technique and proves to fold into a duplex stabilized antiparallel G‐quadruplex structure. Using BG2 as molecular probe, AP heterodimers are found to be expressed on several kinds of cancer cells. As an affinity ligand, BG2 could isolate AP heterodimers from cell lysate. BG2 is also demonstrated to be applicable for tumor imaging in mice xenografted with cells highly expressing AP heterodimers. AP isozymes are found in several tissues and blood throughout the body, but the function and tissue distribution of AP heterodimers are totally unknown; therefore, BG2 could serve as a molecular probe to uncover the mystery of AP heterodimers. The generation of aptameric probes by cell‐SELEX will open up a new situation for the study of protein dimers.

Determination of serum bone-specific alkaline phosphatase isoenzyme activity in captive Asian elephants (Elephas maximus) using an agarose gel electrophoresis method.

The bone-specific alkaline phosphatase (ALP) isoenzyme activity was measured in 51 serum samples from four captive Asian elephants (Elephas maximus) using a conventional method with wheat germ lectin precipitation and a commercial agarose gel electrophoresis (AGE) kit; the isoenzymes were designated as bone-specific ALP (BAP) and ALP isoenzyme 3 (ALP3), respectively. This study examined the suitability of the AGE kit for analyzing blood biochemistry in Asian elephants. The serum ALP3 and BAP activities were strongly positively correlated and met the evaluation criteria for agreement using Bland-Altman analysis. The results indicate that the AGE kit can be used to examine the blood biochemistry in Asian elephants instead of the conventional method.

Diagnostic value of serum osteomarkers in moderate and severe periodontal disease

The purpose of the study was to establish the diagnostic informative value of the concentration of osteomarkers in the serum to assess the severity of the osteodestructive component in chronic generalized periodontitis (HGP) prior to surgery and the prognosis of the effectiveness of surgical treatment of the disease. 187 patients with moderate and severe HGP who underwent bone and plastic insertion during the patch operations were examined. In the blood serum, the concentration of osteoprotegerin, ligand of the soluble activator of the kappa B nucleation factor (sRANKL) was initially determined and at 8 and 12 months after the operation, bone isoenzyme of alkaline phosphatase, osteocalcin, C-terminal telopeptides of degradation of mature type 1 collagen (β-CrossLaps). It was found that in assessing the severity of osteodestructive processes in the periodontium in HGP, the serum concentration of sRANKL and β-CrossLaps is informative. When the sRANKL content in the blood serum exceeds 0,48 pmol/l, and β-CrossLaps exceeds 0,795 ng/ml, it is possible to judge the high activity of osteoclasts, which is accompanied by a pronounced risk of irreversibility of the osteodestructive component and the lack of effectiveness of surgical treatment.

Dynamics of bone metabolism markers in oral fluid after surgical treatment of chronic periodontal disease with various osteoplastic materials

The aim of the work was to assess the balance between osteosynthetic and osteodestructive processes in the oral cavity in patients with chronic generalized periodontitis (CGP) of moderate and severe severity in the dynamics of a remote period of patchwork using various bone-plastic materials (BPM) based on xenogeneic hydroxyapatite (HA), β-tricalcium phosphate (TCP). 123 patients with CGP were examined. Depending on the type of BPM, two groups were distinguished by composition in the course of patchwork operations. Patients of group 1 (n=61) received BPM on the basis of xenogeneic HA, 2 groups (n=62) on the basis of β-TCP. Initially and after surgery at 8 and 12 months in the oral fluid, the concentration of osteoprotegerin (OPG), the ligand of the soluble activator of the kappa B nucleation factor (sRANKL), the bone isoenzyme of alkaline phosphatase (BAP), was determined by an immunoenzyme method. As a result of the study, it was found that in patients with moderate-bodied CGP after surgical treatment, restriction of osteoclast activity with a decrease in sRANKL due to an increase in OPG in the oral fluid, an increase in osteoblast activity with BAP secretion is most pronounced when using β-TCP-based BPM at 8 months. After surgery with an average severity of the disease. Less pronounced changes in bone metabolism in the oral cavity are detected with the use of BPM on the basis of HA. In severe CGP, changes in bone homeostasis in the oral cavity after scrappy operations with BPM insertion based on TCP or HA are not expressed and are observed only after 12 months. Thus, the most effective changes in bone metabolism develop with the use of TCP as BPM.

Retrospective evaluation of a local protocol used to enhance laboratory savings through minimizing the performance of alkaline phosphatase isoenzyme analysis.

Alkaline phosphatase isoenzyme analysis is an expensive and time-consuming laboratory test. We evaluated the effect of a locally derived screening algorithm for alkaline phosphatase isoenzyme requests on the number of alkaline phosphatase isoenzyme analyses performed, laboratory cost and patient care. A total of 110 alkaline phosphatase isoenzyme analysis requests from the year 2015 were reviewed and subsequent alkaline phosphatase concentrations were monitored over a two-year period, to determine if the decision of performing/not performing alkaline phosphatase isoenzyme analysis, based on the algorithm, had an impact on patient care and laboratory cost. All alkaline phosphatase isoenzyme analysis requests with two consecutive elevated alkaline phosphatase concentrations (>upper limit of reference interval) were screened and, subject to the gamma glutamyl transferase being within the reference interval, either Bone alkaline phosphatase or 25 hydroxyvitamin D was measured depending on the age of the patient. Compliance with this algorithm led to the normalization of subsequent serum alkaline phosphatase in 97% of patients without requiring alkaline phosphatase isoenzyme analysis. The cost of performing Bone alkaline phosphatase and 25 hydroxyvitamin D in-house was £778.50, while the cost of performing alkaline phosphatase isoenzyme analysis would have been £3040. This resulted in a laboratory saving of £2261.50. Implementation of this algorithm led to a significant reduction in alkaline phosphatase isoenzyme analysis, without compromising patient care. Total savings could be increased if 25 hydroxyvitamin D was used as a first-line test, for all patients with an elevated alkaline phosphatase and a normal gamma glutamyl transferase regardless of age. This algorithm is cost-effective and can be implemented in laboratories with 25 hydroxyvitamin D assay.

L’hypophosphatasie

Hypophosphatasia is a rare inherited skeletal disorder caused by loss-of function mutations in the APLP gene that encodes the tissue-nonspecific isoenzyme of alkaline phosphatase (TNSALP). There is a great variability of clinical expression. The presentation varies from a lethal neonatal presentation to mild manifestations in adulthood. In adults clinical manifestations include fractures, with recurrent metatarsal fractures and slowly healing, atypical femoral fractures, dental anomalies, chondrocalcinosis with crystalline arthritis, muscle pain. There is poor recognition of low alkaline phosphatase values. However, this diagnosis is important in order to avoid the use of antiresorptive therapy in case of fracture. The management of hypophosphatasia is provided by a multidisciplinary team, in collaboration with reference centers for rare bone diseases; it includes symptomatic measures and enzymatic replacement therapy (asfotase alfa) is an approved treatment for pediatric-onset hypophphosphatasia now available.

Alkaline phosphatase: a potential biomarker for stroke and implications for treatment.

Stroke is the fifth leading cause of death in the U.S., with more than 100,000 deaths annually. There are a multitude of risks associated with stroke, including aging, cardiovascular disease, hypertension, Alzheimer's disease (AD), and immune suppression. One of the many challenges, which has so far proven to be unsuccessful, is the identification of a cost-effective diagnostic or prognostic biomarker for stroke. Alkaline phosphatase (AP), an enzyme first discovered in the 1920s, has been evaluated as a potential biomarker in many disorders, including many of the co-morbidities associated with stroke. This review will examine the basic biology of AP, and its most common isoenzyme, tissue nonspecific alkaline phosphatase (TNAP), with a specific focus on the central nervous system. It examines the preclinical and clinical evidence which supports a potential role for AP in stroke and suggests potential mechanism(s) of action for AP isoenzymes in stroke. Lastly, the review speculates on the clinical utility of AP isoenzymes as potential blood biomarkers for stroke or as AP-targeted treatments for stroke patients.

Accelerated Aging and Clearance of Host Anti-inflammatory Enzymes by Discrete Pathogens Fuels Sepsis

Sepsis is a life-threatening inflammatory syndrome accompanying a bloodstream infection. Frequently secondary to pathogenic bacterial infections, sepsis remains difficult to treat as a singular disease mechanism. We compared the pathogenesis of murine sepsis experimentally elicited by five bacterial pathogensand report similarities among host responses to Gram-negative Salmonella and E.coli. We observed that a host protective mechanism involving de-toxification of lipopolysaccharide by circulating alkaline phosphatase (AP) isozymes was incapacitated during sepsis caused by Salmonella or E.coli through activation of host Toll-like receptor 4, which triggered Neu1 and Neu3 neuraminidase induction. Elevated neuraminidase activity accelerated the molecular aging and clearance of AP isozymes, thereby intensifying disease. Mice deficient in the sialyltransferase ST3Gal6 displayed increased disease severity, while deficiency of the endocytic lectin hepatic Ashwell-Morell receptor was protective. AP augmentation or neuraminidase inhibition diminished inflammation and promoted host survival. This study illuminates distinct routes of sepsis pathogenesis, which may inform therapeutic development.