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

A radioimmunoassay for transforming growth factor alpha (TGF-alpha) using synthetic rat sarcoma transforming growth factor and its rabbit polyclonal antibody has been developed. Using radioimmunoassays, the urinary TGF-alpha and epidermal growth factor (EGF) concentrations in 31 patients with hepatocellular carcinoma (HCC), 15 probable HCC, four metastatic liver cancer, and 33 age, sex-matched healthy controls were determined. For the first time, we have shown that the average TGF-alpha concentration for HCC patients was 21.5 +/- 20.3 micrograms per g creatinine, significantly higher than that of healthy subjects, 4.9 +/- 2.8 micrograms per g creatinine (P less than 0.001). There was no statistical difference in the level of EGF between HCC patients and controls (40.9 +/- 29.3 versus 46.2 +/- 16.6 micrograms per g creatinine; P greater than 0.05). The ratio of EGF/TGF-alpha between HCC patients (3.37 +/- 4.42) and controls (15.5 +/- 13.0) was significantly different (P less than 0.001). Among patients, 65% (20 of 31) of HCC cases and 87% (13 of 15) of probable HCC cases showed a marked elevation of TGF-alpha levels. We found only 16% (five of 31) of HCC cases with increased EGF level. EGF excretion was inversely age related. Serum total protein concentration and alkaline phosphatase activity were positively correlated to EGF concentration (r = 0.522, P less than 0.01 and rt = 0.393, P less than 0.05, respectively). There was no correlation between biochemical functions of liver and TGF-alpha concentration in HCC patients. Our results also suggested that TGF-alpha may be a useful complementary tumor marker for management of patients with clinical manifestation of HCC who have low alpha-fetoprotein levels.
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PMID:Elevation of transforming growth factor alpha and its relationship to the epidermal growth factor and alpha-fetoprotein levels in patients with hepatocellular carcinoma. 243 30

The human septal cartilage is of ectodermal origin and contributes to midfacial growth and development. Acromegaly is an endocrine disease due to growth hormone (Gh) excess originating from a somatotrophic adenoma of the pituitary gland. Excessive Gh levels lead to high insulin-like growth factor I (IGF I) concentrations, which are known to stimulate cartilage growth in vivo and in vitro. One of the salient clinical pictures is coarsening of the midface and enlargement of the septal cartilage. Septal cartilage was obtained from 8 acromegalic patients during transnasal hypophysectomy and from 10 healthy adults during septoplasty to analyse the following aspects of cartilage biochemistry, metabolism and growth. 1. Intracellular glycogen, the major source of energy of chondrocytes, was determined enzymatically and found to be drastically reduced in acromegaly. 2. Several intracellular enzymes, related to biomatrix degradation, showed a strict local pattern of distribution. Cathepsin B activity, a neutral proteinase degrading both the helical and nonhelical region of the collagen molecule was significantly increased in acromegaly, whereas alkaline phosphatase activity, an enzyme related to mineralization of the cartilage at the chondroosseous junction was depressed in acromegaly. 3. The cell density in some areas of the septal cartilage was increased in acromegaly, whereas the clonal proliferation rate of its chondrocytes in response to serum and growth factors was decreased. Chondrocytes both of healthy adults and acromegalic patients could be effectively stimulated by insulin-like growth factor I and II and to a lesser extent by epidermal growth factor.
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PMID:Human nasal septal cartilage: analysis of intracellular enzyme activities, glycogen content, cell density and clonal proliferation of septal chondrocytes of healthy adults and acromegalic patients. 252 4

Binding of epidermal growth factor (EGF) stimulates tyrosyl protein kinase activity of its receptor in the epidermis. This tyrosine residue phosphorylation is thought to be one mechanism by which EGF mediates its effects such as growth stimulation. To modulate a cellular response to EGF, an enzyme which dephosphorylates phosphotyrosyl residues should be present to oppose the effect of the tyrosyl kinase activity of the EGF receptor. We have identified an enzyme in the neonatal mouse epidermis which has the ability to dephosphorylate tyrosyl residues in vitro on EGF receptors. This phosphatase is a soluble protein with a molecular weight greater than 10,000 daltons and shows optimum activity at neutral pH. This epidermal tyrosyl protein phosphatase is not inhibited by tartrate, ATP, and micromolar levels of zinc, but is inhibited by millimolar levels of zinc, magnesium, manganese, and fluoride. Unlike other well-known phosphotyrosyl phosphatases, alkaline phosphatase, and calcineurin, this enzyme is not inhibited by EDTA. Thus, we have identified and partially characterized a possibly unique phosphotyrosyl phosphatase from the epidermis.
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PMID:Identification of a phosphotyrosyl-protein phosphatase in mouse epidermis. 253 66

Proximal tubules were prepared from rat kidney cortex by collagenase digestion and purified by Percoll gradient centrifugation. Their enrichment was estimated by comparing the specific activities of various cell-specific enzymes in homogenates of renal cortex and of the isolated tubules. The tubules were cultured in a 50:50 mixture of Dulbecco's modified Eagle's and Ham's F12 media supplemented with insulin, transferrin, epidermal growth factor, hydrocortisone, and prostaglandin E1. After 2 to 3 d an extensive outgrowth of epithelial cells developed from the attached tubules. After 5 to 7 d near confluent monolayers were obtained. Hormonal responsiveness, marker enzyme activities, and transport properties were determined to further characterize the primary cultures. The cultured cells exhibited increased cyclic AMP production in response to parathyroid hormone but not calcitonin or vasopressin, consistent with the absence of cells derived from distal and collecting tubules. The cells also retained significant levels of 25-hydroxyvitamin D3-1 alpha-hydroxylase, alkaline phosphatase, and gamma-glytamyl-transpeptidase, three enzymes that are primarily associated with the proximal tubule. The cultured epithelial cells also exhibit a Na+-dependent phosphate and glucose transport systems. Therefore, the cells retain many functional properties that are characteristic of proximal tubules. Thus, the primary cultures should be suitable for the study of processes that occur specifically within this segment of the rat nephron.
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PMID:Characterization of primary cell cultures derived from rat renal proximal tubules. 254 89

A human dental pulp tissue was explanted in culture and the outgrowing cells were transfected with the plasmid, pMT1-neo, which included the early region of SV 40 DNA and the neomycin-resistant gene. The transfected cells were cloned and cultured beyond the period of senescence for the non-transfected HOP cells, over 170 passages (360 population doubling levels and 730 days). The characteristics of the transfected LSC cells and the non-transfected HOP cells were investigated during in vitro aging. The results were as follows: 1. The alkaline phosphatase (ALPase) activity of the HOP cells decreased as the culture passages increased. In contrast, the ALPase activity of the LSC cells did not change during the entire serial culture period. 2. The ALPase inhibitory test indicated that the ALPase in the LSC cells was the bone/liver/kidney type. 3. The addition of 250 micrograms/ml of L-ascorbic acid resulted in an increased collagen synthesis compared with that of 50 micrograms/ml. 4. The growth rate and the ALPase activity of the LSC cells were affected by 1 alpha, 25-dihydroxyvitamin D3, L-ascorbic acid, beta-sodium glycerophosphate, epidermal growth factor or transforming growth factor-beta even after the serial culture. These results suggest that the LSC cells preserve some properties of the dental pulp and may be useful in the future research for exploring the mechanisms of the dental hard tissue formation and for testing the biocompatibility of the dental restorative materials.
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PMID:[Immortalization of human dental pulp cells with transfecting of the plasmid, pMT1-neo]. 255 37

The present study examines how the mitogenic and differentiation functions of transforming growth factor-beta (TGF-beta) are modulated by basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) in primary cultures of rat osteoblast-like (ROB) cells. TGF-beta, bFGF, and EGF individually stimulated [3H]thymidine incorporation and cell proliferation in a dose range of 0.01-10 ng/ml. When studied in combination, high doses of bFGF and EGF were additive to low doses of TGF-beta. The additive effects of bFGF and EGF on mitogenesis diminished with increasing doses of TGF-beta. These three factors also decreased alkaline phosphatase activity individually within the same dose range. When cells were treated with the combined factors, only high doses of bFGF and EGF were additive to the TGF-beta inhibition. We were unable to detect any change in collagen synthesis with each individual factor or in combined treatments. In addition, TGF-beta or bFGF alone or in combination did not affect fibronectin synthesis. Our studies showed that the biological functions of TGF-beta can be modulated by bFGF and EGF in ROB cells. The pattern of modulation is varied depending on the specific function examined.
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PMID:Modulation of transforming growth factor-beta actions in rat osteoblast-like cells: the effects of bFGF and EGF. 263 28

Transforming growth factor beta (TGF-beta) regulates cell growth and differentiation. Since it is abundant in bone, we have studied the effect of the polypeptide upon the growth and phenotypic expression of murine osteoblastic cells in monolayer culture. Its actions were compared to those of epidermal growth factor (EGF), another hormonally active polypeptide known to alter bone cell function. Picogram amounts of TGF-beta were found to inhibit the growth and phenotype (alkaline phosphatase and cAMP response to parathyroid hormone) of the clonal nontransformed MC3T3-E1 osteoblastic cell line. EGF also inhibited phenotypic expression, although at higher (nanogram) concentrations, but stimulated cell growth. The low concentration of TGF-beta required to inhibit growth and phenotype of osteoblastic cells together with its abundance in bone suggest that TGF-beta may be an important regulator of bone cell function.
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PMID:Transforming growth factor-beta reduces the phenotypic expression of osteoblastic MC3T3-E1 cells in monolayer culture. 283 96

In cultured normal rat liver epithelial cells, the specific activity and/or isozyme expression of NADH-diaphorase (NADH-D), pyruvate kinase (PK), glucose-6 phosphate dehydrogenase (G6PD), gamma-glutamyl transpeptidase (GGT), and alkaline phosphatase (AP) were markedly dependent on the growth state of the cultures. Proliferating, preconfluent cells had higher specific activities of PK, NADH-D, and G6PD but lower activities of GGT and AP than did the more stationary confluent cells. Addition of epidermal growth factor [EGF] to the media of proliferating cells enhanced the specific activities of PK, NADH-D, G6PD, GGT, and lactate dehydrogenase (LDH) of these cells, but the specific activity of AP was markedly depressed. The increase in activity of PK and GGT by EGF appeared to involve new protein synthesis, whereas the effect of EGF on AP appeared to involve the EGF-directed suppression of the synthesis of a form of AP that is produced exclusively by cells in confluent cultures. Furthermore, the preconfluent cells were more responsive to the action of EGF on AP than were confluent cells, i.e., the EGF-mediated decrease in AP activity was seen at lower concentration in preconfluent than in confluent cells. Paradoxically, confluent cells exhibited a two-to threefold higher capacity to bind [125 I]EGF because of an increase in surface receptor number. The results of this study indicate that enzymatic or other biochemical studies performed on cultured cells must take into account the growth-state of the cultures. EGF can modulate enzyme activity in growing and nongrowing cells; one effect of EGF is to maintain higher activity of glycolytic enzymes, suggesting that EGF or EGF-like factors may contribute to the high rate of glycolysis in certain neoplasms.
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PMID:The effects of epidermal growth factor and the state of confluence on enzymatic activities of cultured rat liver epithelial cells. 286 16

The postnatal development of brush border enzyme activities, namely maltase, trehalase, alkaline phosphatase, gamma-glutamyltranspeptidase, and leucylnaphthylamidase, as well as the ontogenic profile of DNA synthesis has been determined in the mouse kidney. In addition, these parameters were evaluated following daily administration of hormones during 3 days to 8-day-old mice. Insulin or epidermal growth factor induced a 34% increase of maltase activity over that of 11-day-old controls. Trehalase activity was precociously and significantly augmented by cortisone alone or combined with thyroxine (p less than 0.05), although thyroxine alone had no influence. Only epidermal growth factor had a significant effect on alkaline phosphatase activity. gamma-Glutamyltranspeptidase activity was significantly decreased when insulin and thyroxine were given simultaneously, but was not modified by any of the hormones injected separately. The level of leucylnaphthylamidase activity was enhanced by 70% after cortisone injection, but it was significantly reduced by thyroxine injected in combination with insulin or cortisone. The incorporation of [3H]thymidine into DNA was increased by 107% after epidermal growth factor administration, but it was decreased by 33% after the cortisone treatment. In spite of this precocious reduction, the level of incorporation was still 2 times higher than that in adult mice. These results show that hormones act separately or in cooperation to accelerate or retard the maturation of the suckling mouse kidney.
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PMID:Effect of hormones on hydrolase activities and DNA synthesis in kidney of the developing mouse. 290 Dec 85

We previously demonstrated that human embryonic mesenchymal cells derived from the palate (HEMP cells) retain alkaline phosphatase (ALP) content and capacity for collagen synthesis after long-term culture, and their growth is markedly stimulated by epidermal growth factor (EGF). There was a dramatic decrease in ALP content and capacity to synthesize collagen in HEMP cells (HEMP-RV cells) persistently infected with rubella virus (RV). EGF increased ALP activity and decreased collagen synthesis in HEMP cells, whereas EGF showed no effect on these activities in HEMP-RV cells. Growth of HEMP-RV cells was slightly reduced compared with that of HEMP cells. EGF stimulated growth of HEMP cells and to a lesser extent of HEMP-RV cells. Binding of 125I-EGF to cell-surface receptors in HEMP-RV cells was, to our surprise, twice as much as that in HEMP cells. However, internalization of bound 125I-EGF in HEMP-RV cells was profoundly diminished. Thus, persistent RV infection causes not only changes in HEMP cell growth and differentiation but a decrease in or loss of HEMP cell responsiveness to EGF. The effects of persistent RV infection on palatal cell differentiation as well as growth may be responsible for the pathogenesis of congenital rubella. Furthermore, since HEMP cells appear to be closely related to osteoblasts, these results suggest a mechanism for RV-induced osseous abnormalities manifested in congenital rubella patients.
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PMID:Altered growth, differentiation, and responsiveness to epidermal growth factor of human embryonic mesenchymal cells of palate by persistent rubella virus infection. 300 47


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