Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.1.3.1 (alkaline phosphatase)
47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Interleukin 6 (IL-6) exerts well-established effects on cells of the immune system as well as on various other cell types. It has been implicated in the control of connective tissue cells in such conditions as rheumatoid arthritis and osteoporosis. We have investigated the effects of recombinant human interleukin-6 (rhIL-6) on human osteoblastlike cells derived from explants of trabecular bone. ROS 17/2.8 cells were used as an additional osteoblastlike cell model system. We were unable to identify any effects of rhIL-6 (5-5000 pg/ml) on the proliferation, alkaline phosphatase activity. osteocalcin production, or release of cytokines or prostaglandins by either osteoblastlike cell model system. Since we have shown previously that these cells release IL-6 in culture, we used a sheep anti-human IL-6 antibody to investigate the possibility that (1) action of added exogenous IL-6 could be masking endogenous production, and (2) endogenous IL-6 may regulate the effects of osteotropic agents on the osteoblastlike cells. Presence of the antibody exerted no detectable effects on 1,25-(OH)2D3-stimulated alkaline phosphatase or on proliferation or TNF production enhanced by IL-1. Thus IL-6 does not appear to be involved in the regulation of osteoblast activity.
...
PMID:Human osteoblastlike cells do not respond to interleukin-6. 170 32

The effects of nandrolone decanoate (ND; 50 mg IM every three weeks) on calcium metabolism and forearm bone density were studied in a randomized trial in 35 women receiving long-term therapy with corticosteroids (CST) for rheumatic disease. The 17 patients who served as controls were on CST therapy for less years and their bone density was higher. Thus a second control group, pair-matched with the active treatment group for age, duration of CST therapy and bone density, was selected retrospectively. At the end of the 18 months' treatment course with ND, forearm bone density was increased by 5.1% (P less than 0.01) but fell by 11.3% (P less than 0.01) and 6.7% respectively in the first and second control group. The patients on ND differed significantly from both control groups in the changes at 6, 12 and 18 months (P less than 0.01). Urinary excretion of hydroxyproline fell significantly in patients receiving ND, whereas the biochemical indices of bone formation did not change (alkaline phosphatase) or increased (osteocalcin; P less than 0.01). In conclusion, nandrolone decanoate therapy may be used in the prevention of CST-induced osteoporosis. It also seems to exert mild inhibition of bone resorption without affecting or even stimulating bone formation.
...
PMID:The prevention of corticosteroid-induced osteoporosis with nandrolone decanoate. 174 68

In this cross-sectional study, the radius bone mineral content (BMC) of 340 postmenopausal women (mean age: 53; mean years since menopause: 5.56) were assessed by single photon absorptiometry (SPA) for determining prevalence rate of postmenopausal osteoporosis in Chengdu, and some factors relative to BMC were investigated. Eighty-five of 340 postmenopausal women were diagnosed osteoporosis by SPA. The prevalence rate, which increases with year since menopause and age, is 25%. There is significant increase in prevalence after the age of 60 years or 5 years since menopause. Sixteen factors were analysed by STEPWISE REGRESSION. The variables selected were serum calcium(SCa), serum alkaline phosphatase (SAkP), urine calcium (UCa), urine hydroxypoline (UH), age, and Para. Fisher DISCRIMINANT ANALYSIS was used for diagnosis with these variables, the accuracy of diagnosis being 75.2%. Our study showed that postmenopausal osteoporosis is a common disease in Chengdu. High SCa, UH, age and low SAkP level may be risk factors of osteoporosis.
...
PMID:[Study on morbidity and relative factors of postmenopausal osteoporosis in 340 women in Chengdu]. 177 38

The effects of 1 alpha-hydroxyvitamin D2 on calcium metabolism in vivo and of 1 alpha, 25-dihydroxyvitamin D2, which is an active metabolite of 1 alpha-hydroxyvitamin D2, on bone metabolism in vitro was studied and compared with that of 1 alpha-hydroxyvitamin D3 or 1 alpha,25-dihydroxyvitamin D3. 1 alpha-Hydroxyvitamin D2 and 1 alpha-hydroxyvitamin D3 was equally potent in stimulating intestinal calcium transport by using the everted sac method and of calcium mobilization from bone in vitamin D-deficient rats. On the other hand, the hypercalcemic activity of 1 alpha-hydroxyvitamin D2 was much lower than that of 1 alpha-hydroxyvitamin D3 in normal mice and rats. 1 alpha,25-Dihydroxyvitamin D2 and 1 alpha,25-dihydroxyvitamin D3 stimulated alkaline phosphatase activity in osteoblastic MC3T3-E1 cells and bone resorption in newborn mouse calvaria maintained in organ culture. These results show that 1 alpha-hydroxyvitamin D2 as well as 1 alpha-hydroxyvitamin D3 promote calcium absorption and may accelerate bone remodelling via direct action on osteoblasts. In addition, they suggest that 1 alpha-hydroxyvitamin D2 may be more useful than 1 alpha-hydroxyvitamin D3 for the treatment of senile osteoporosis, because hypercalcemia is one of the major side effects of 1 alpha-hydroxyvitamin D3.
...
PMID:Effects of vitamin D2 analogs on calcium metabolism in vitamin D-deficient rats and in MC3T3-E1 osteoblastic cells. 178 69

Bone-alkaline phosphatase was determined in patients at risk of osteoporosis due to treatment with oral corticosteroids, and in patients at risk of increased bone synthesis because of treatment with cyclosporin. Both a significant decrease of bone-alkaline phosphatase during corticosteroid treatment, and a significant increase of bone-alkaline phosphatase during cyclosporin treatment could be demonstrated. It is concluded that bone-alkaline phosphatase is a useful parameter for monitoring changes in bone formation.
...
PMID:Bone-alkaline phosphatase as indicator of bone formation. 179 Jun 24

We examined the effect of nicotine on cellular proliferation, as measured by [3H]thymidine (TdR) incorporation and cell count, and on alkaline phosphatase activity in UMR 106-01 rat osteoblastic osteosarcoma cells. The cells were cultured with varying concentrations of nicotine in serum-free medium for 2 to 72 hours. Nicotine produced a dose-dependent suppression of TdR incorporation, with maximum suppression seen at 10 mM (7% of control); the EC50 for suppression of TdR incorporation was 10 microM. 1 microM nicotine decreased cell number by 20% to 30%. The time course of the effect of 100 microM nicotine on DNA synthesis was measured by TdR incorporation. TdR uptake was measured at 2, 4, 6, 24, 48, and 72 hours. After the addition of nicotine, the following biphasic response in TdR incorporation was observed: a 15% decrease at 2 hours, recovery to near control value at 6 hours, a 27% decrease by 24 hours, and a maximum decrease of 88% by 48 hours. Over a dose range of 1 nM to 10 mM, nicotine produced a dose-dependent increase in alkaline phosphatase activity with maximum stimulation seen at 1 microM (189% of control). We conclude that nicotine suppresses cellular proliferation and stimulates alkaline phosphatase activity in UMR 106-01 osteoblast-like cells. These results may be of significance in the development of osteoporosis and alveolar bone loss associated with the use of tobacco.
...
PMID:Effects of nicotine on cellular function in UMR 106-01 osteoblast-like cells. 179 80

Osteocalcin is a 49 amino acid non collagenous bone matrix protein which is synthesized by the osteoblasts. The serum levels of osteocalcin have been found to be a specific biochemical parameter of bone formation. We determined the serum levels of osteocalcin, parathyroid hormone, calcitonin and alkaline phosphatase as well as the 2 hour fasting hydroxyproline excretion in 26 patients with postmenopausal osteoporosis and in 24 postmenopausal control subjects. Serum levels of osteocalcin were significantly lower in the patients with postmenopausal osteoporosis than in the control subjects (p less than 0.002). In contrast, serum levels of parathyroid hormone, calcitonin, alkaline phosphatase and the 2 hour hydroxyproline excretion in the patients with postmenopausal osteoporosis and the control subjects were not statistically different. Our data give evidence of a decreased bone formation in patients with postmenopausal osteoporosis.
...
PMID:Decreased serum osteocalcin levels in patients with postmenopausal osteoporosis. 179 22

Diabetes and osteoporosis are linked. The question remains, however, as to whether insulin has any direct effect on bone formation. To test this hypothesis we have measured, as a marker of osteoblast activity, alkaline phosphatase (ALP) released by rat limb intact bones incubated in the presence and in the absence of physiological concentration of insulin. The results indicate that insulin significantly (p less than 0.012) increases ALP by a mean value of 48% (from 5.4% to 215%) over matched controls. We conclude that insulin has a direct stimulatory effect on osteoblast activity, and that in the absence of this effect, as in diabetes, bone loss might occur.
...
PMID:[Effect of insulin on the activity of bone alkaline phosphatase in culture]. 181 19

The non-invasive assessment of bone turnover has received increasing attention over the past few years because of the need for sensitive markers in the clinical investigation of osteoporosis. Markers of bone formation include serum total and bone-specific alkaline phosphatase, serum osteocalcin, and measurement of serum type I collagen extension peptides. Assessment of bone resorption can be achieved with measurement of urinary hydroxyproline, urinary excretion of the pyridinium crosslinks (Pyr and D-Pyr), and by measurement of plasma TRAP activity. For the screening of bone turnover in women at the menopause, and for the assessment of the level of bone turnover in elderly women with vertebral osteoporosis, serum osteocalcin and urinary Pyr and D-Pyr appear to be the most sensitive markers so far. Programmes combining bone mass measurement and assessment of bone turnover in women at the time of the menopause have been developed in an attempt to improve the assessment of the risk for osteoporosis. Efforts are being made to develop more convenient assays and to identify other markers of bone turnover. In the future a battery of various specific markers is likely to improve the assessment of the complex aspects of bone metabolism, especially in osteoporosis.
...
PMID:What do we know about biochemical bone markers? 182 19

We have used the cynomolgus macaque as a model for the study of the effects of endogenous and exogenous sex steroid hormones on atherosclerosis and osteoporosis. As in human beings, premenopausal female cynomolgus macaques develop much less extensive coronary artery atherosclerosis than their male counterparts. Furthermore, surgical menopause results in a more atherogenic plasma lipoprotein pattern and an approximate doubling of atherosclerosis extent. Frequent pregnancy, a hyperoestrogenic state, results in an approximate 50% reduction in atherosclerosis extent. Physiological replacement with 17 beta-oestradiol alone or in combination with progesterone prevents the increase in coronary artery atherosclerosis extent associated with ovariectomy. This effect is independent of plasma lipoprotein concentrations and appears to be accounted for, at least in part, by an inhibitory effect of oestrogen replacement therapy on the uptake and degradation of LDL by the artery wall. Also, as in human beings, treatment with certain types of combination oral contraceptives results in marked decreases in plasma HDL-C concentration. Nonetheless, coronary artery atherosclerosis extent is reduced in monkeys by oral contraceptive treatment, and this effect is most pronounced among animals at highest risk due to theoretically adverse plasma lipoprotein profiles. It appears that, as with oestrogen replacement therapy, this effect can be accounted for, at least in part, by an inhibition of the uptake and degradation of low density lipoprotein by the artery wall. The monkey also appears to be a good model for studies of postmenopausal bone loss. As in women, surgical menopause results in significant diminution of bone mineral density and bone mineral content. Also, serum biomarkers of bone turnover (total alkaline phosphatase, acid phosphatase, tartrate-resistant acid phosphatase and osteocalcin) are increased in surgically postmenopausal monkeys, indicating increased bone turnover resulting from the surgical menopause. These increases in bone loss and indices of bone turnover were prevented by physiological oestrogen replacement therapy. Cynomolgus monkeys seem to be exceptionally useful models for studies of the effects of sex steroid hormones on atherosclerosis and osteoporosis, two major public health problems in postmenopausal women.
...
PMID:Effects of oestrogens and progestogens on coronary atherosclerosis and osteoporosis of monkeys. 182 26


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---