Expression Of Bone-specific Alkaline Phosphatase Research Articles

Periodontal inflammation triggers a site-specific and wide radius of calcium metabolic effects on alveolar bone.

There is a close relationship between inflammation and bone remodeling in the periodontium. However, previous studies have not delineated the alterations in calcium (Ca) metabolism during periodontitis progression. The aim of this current investigation was to examine Ca dynamics in alveolar bone of rats during progression of ligature-induced periodontal inflammation by using 45 Ca, which is an index of hard tissue neogenesis. To induce periodontitis, the maxillary right first molar (M1) of 8-week-old male rats was ligated with a silk suture for 1, 3, 7, and 28days. The left M1 was not ligated as a control. To evaluate resultant changes in bone neogenesis, 45 CaCl2 was injected intraperitoneally 24hours before euthanasia. The left-and-right palatal mucosa, molar teeth (M1 and M2), and alveolar bone were harvested for evaluation of 45 Ca radioactivity using a liquid scintillation counter. The distribution of 45 Ca in maxillary tissues was evaluated using autoradiography (ARG). In addition, we analyzed the bone volume fraction (BV/TV) and bone mineral density (BMD) of the alveolar bone by micro-computed tomography. To investigate the number of osteoclasts and osteoblasts, tartrate-resistant acid phosphatase (TRAP) and bone-specific alkaline phosphatase (BAP) were measured by an enzymatic assay and immunohistochemistry, respectively. 45 Ca radioactivity in the alveolar bone of the ligature side decreased by 8% compared to the unligated control-side on day 1, whereas on day 7, it markedly increased by 33%. The 45 Ca levels in the gingival tissue and molar teeth were slightly but significantly lower than the control-side on day 1 and higher from day 3 to 28. The variation in 45 Ca levels for the alveolar bone was greater and specific compared with other tissues. Furthermore, on day 7, ARG data revealed that 45 Ca on the control side was primarily localized to the periodontal ligament (PDL) space and alveolar bone crest and barely detected in the gingival tissues and deeper parts of the alveolar bone. On the ligature side, 45 Ca disappeared from the PDL and alveolar crest, but instead was broadly and significantly increased within the deeper zones of the alveolar bone and furcation areas and distant from the site of ligature placement and periodontal inflammation. In the shallow zone of the alveolar bone, these changes in 45 Ca levels on day 7 were consistent with decreases in the bone structural parameters (BV/TV and BMD), enhanced osteoclast presence, and suppressed levels of BAP expression in osteoblasts. In contrast, the deep zone and furcation area showed that TRAP-positive cells increased, but BAP expression was maintained in the resorption lacunae of the alveolar bone. During periodontitis progression in rats, 45 Ca levels in the alveolar bone exhibited biphasic alterations, namely decreases and increases. These data indicate that periodontitis induces a wide range of site-specific Ca metabolism alterations within the alveolar bone.

Effects of Yishengukang decoction on expression of bone-specific alkaline phosphatase, carboxyterminal propeptide of type I procollagen, and carboxyterminal cross-linked telepeptide of type I collagen in malignant tumor patients with bone metastasis

OBJECTIVETo investigate the effect of Yishengukang decoction on the expression of the metabolic bone markers, bone-specific alkaline phosphatase (BAP), carboxyterminal propeptide of type I procollagen (PICP), and carboxyterminal cross-linked telepeptide of type I collagen (ICTP), in cancer patients with bone metastasis. METHODSPatients (n = 180) were divided into three groups: (a) bone metastasis patients treated with Yishengukang and pamidronate disodium injection (treatment group, n = 60); (b) bone metastasis patients treated with pamidronate disodium injection alone (control group, n = 60); (c) cancer patients without metastatic bone lesion (non-bone metastasis group, n = 60). Serum levels of the metabolic markers BAP, PICP, and ICTP were detected by enzyme-linked immunosorbent assay pre- and post-therapy. RESULTSA significant decrease in serum BAP level was observed in the treatment group compared with the control group. However there were no significant differences in serum levels of PICP and ICTP before or after treatment compared with the control group. CONCLUSIONYishengukang decoction combined with pamidronate disodium injection reduced serum BAP level to a greater extent that pamidronate disodium injection alone. Furthermore, the combined therapy was more beneficial in regulating imbalanced bone metabolism after bone metastasis, and may represent the molecular mechanism underpinning the effects of Yishengukang decoction.

Association between Absolute Tumor Burden and Serum Bone‐Specific Alkaline Phosphatase in Canine Appendicular Osteosarcoma

In dogs with appendicular osteosarcoma (OSA), increased pretreatment serum bone-specific alkaline phosphatase (BALP) activity is a negative prognostic factor, associated with shorter disease-free intervals and survival times, but a biologic basis for observed differential serum BALP activities in canine OSA patients remains incompletely defined. Serum BALP activity will correlate with absolute tumor burden in dogs with OSA. This study included 96 client-owned dogs with appendicular OSA. In canine OSA cell lines, the expression and membranous release of BALP was evaluated in vitro. The correlation between serum BALP activity and radiographic primary tumor size was evaluated in OSA-bearing dogs. In dogs developing visceral OSA metastases, serial changes in serum BALP activities were evaluated in relation to progression of macroscopic metastases, and visceral metastatic OSA cells were evaluated for BALP expression. In vitro, BALP expression was not associated with either tumorigenic or metastatic phenotype, rather the quantity of membranous BALP released was proportional with cell density. In dogs devoid of macroscopic metastases, there was a positive correlation between serum BALP activity and absolute primary tumor size. In dogs with progressive OSA metastases, serum BALP activity increased and coincided with the development of macroscopic metastases. OSA cells derived from visceral metastatic lesions retained BALP expression. Tumor burden is a determinant of serum BALP activity in dogs with appendicular OSA. The association between increased pretreatment BALP activity and negative clinical prognosis may simply be attributed to greater initial tumor burden, and consequently more advanced tumor stage.

Osteogenic potential and responsiveness to leptin of mesenchymal stem cells between postmenopausal women with osteoarthritis and osteoporosis

The aim of this study was to compare the osteogenic potential and responsiveness to leptin of mesenchymal stem cells (MSCs) from bone marrow between postmenopausal women with osteoarthritis (OA) and osteoporosis (OP). MSCs of the proximal femur from OA and OP donors were cultured under control and different experimental mediums. After verifying the availability of primary cells, their osteogenic potential and responsiveness to leptin were compared between two groups. Similar patterns of cell growth were shown in both OA and OP groups. However, after the sixth passage, the viability of undifferentiated cells decreased more in OP than in OA donors. Under the same osteogenic supplements condition, the mRNA expression of osteogenesis-specific genes, osteocalcin (OC) and alkaline phosphatase (ALP) were higher in OA group. Comparison of bone matrix mineralization was parallel to that of mRNA expression. The level of bone-specific ALP (BAP) was higher in cells from donors with OA, whereas osteoprotegerin (OPG) was higher in OP group. This difference in BAP expression proved to be insignificant after the administration of leptin. Although leptin upregulated the expression of OPG, a significant difference still existed between OA and OP. In conclusion, differential osteogenic potential and responsiveness to leptin of MSCs were noted between postmenopausal women with OA and OP. Differential biological behavior of MSCs seems to be partly related to the different distribution of bone mass between OA and OP populations.

Expression of bone specific alkaline phosphatase on human B cells

We here report for the first time that human B cell express bone specific alkaline phosphatase. Using a monoclonal antibody against bone specific alkaline phosphatase (BAP), its expression was detected in approximately 50% of circulating B cells but not T cells. Using RT-PCR, BAP specific transcripts were detected in the B cells expressing surface BAP but not in those not expressing BAP. Activation of B lymphocytes using phorbal ester, PMA with or without ionomycin did not affect change in BAP expression. Following stimulations with Pokeweed Mitogen (PWM) and Staphylococcus aureus Cowan I (SAC), BAP expression on human B cells was increased. This paralleled the increase in production of immunoglobulins and BAP, detected by ELISA and enzyme assay with p-nitrophenyl phosphate, respectively. The role of BAP in B cell biology is uncertain. However, these data suggest that BAP may play an important role in differentiation and maturation of human B cells.

Expression of bone specific alkaline phosphatase on human B cells (86.18)

Abstract A complex relationship exists among the molecules involved in the development of the immune system and of the bony skeleton. Molecules involved in one system can exert effects on the other system. Alkaline phosphatase (AP) is produced at high levels by osteoblasts and it plays an important role in bone remodeling. AP activity is also found on human B cells although the exact nature is not clearly understood. The purpose of this study is to determine the nature of expression of AP in human lymphocytes. Using a monoclonal antibody against bone specific alkaline phosphatase (BAP), its expression was detected in approximately 50% of circulating B cells but not T cells. These cells were distinct from the circulating osteoblasts. Lymphocyte stimulation by TPA with or without ionomycin, did not change BAP expression. Using RT-PCR, BAP specific transcripts were detected in the B cells expressing surface BAP but not in those not expressing BAP. The expression of BAP on B cells was similar in children as in adults. Its expression on transformed B cell lines was variable and EBV-transformed B cells did not express BAP. BAP was predominantly expressed in the CD27negative subpopulation. As CD27 is thought to be a marker for memory lymphocytes, it might be inferred that BAP is down-regulated in the memory B cells. Collectively, these data suggest that BAP may play an important role in the differentiation and maturation of human B cells.

Proliferation, differentiation, and gene expression profile of osteoblast of patient with spondyloepiphyseal dysplasia tarda with progressive arthropathy

To explore the proliferation, differentiation, and gene expression profile of the osteoblasts (OBs) of patient with spondyloepiphyseal dysplasia tarda with progressive arthropathy (SEDT-PA). OBs from the head of femur of a SEDT-PA patient resected during operation were cultured. ELISA was used to examine the bone-specific alkaline phosphatase (BAP), osteocalcin (OC), and osteoprotegrin (OPC) in the lysate of OBs. The proliferation and survival of the OBs were evaluated with MTT method and (3)H-TDR incorporation. Flow cytometry was used to observe the cell cycle. Northern blotting was used to evaluate the mRNA expression of WISP3, a member of the CCN family, mRNA in the OBs. Gene differential expression microarray was used to determine the cDNA expression. Osteoblasts from the head of femur of a patient about the same age with fracture of femur neck was used as control. The cultured OBs from the SEDT-PA patient showed a higher survival capacity (0.86 +/- 0.04 vs 0.71 +/- 0.10) and more (3)H-TDR incorporation (1363 +/- 350 vs 867 +/- 128). The expressions of OC and OPG were down-regulated to the 1/4.3 and 1/4.69 of the control respectively. There was no significant difference in the expression of BAP. WISP3 was very lowly expressed in the OBs of the SEDT-PA patient. In comparison with the normal control, there were up-regulation of 22 genes, including those coding chemotactic factors and inflammatory factors, and down-regulation of 16 genes in the OBs of the SEDT-PA patient with a synthetic effect of more rapid proliferation of OBs and reduction of synthesis of extracellular matrix, resulting in osteopenia. Not significantly different between SEDT-PA patient and normal person, the WISP3 expression may not be a direct factor of SEDT-PA.