scholarly journals Induction of germ-cell alkaline phosphatase by butyrate and cyclic AMP in BeWo choriocarcinoma cells

1993 ◽  
Vol 296 (1) ◽  
pp. 59-65 ◽  
Author(s):  
J F Telfer ◽  
C D Green

BeWo choriocarcinoma cells synthesize two alkaline phosphatase isoenzymes: germ-cell alkaline phosphatase and tissue-unspecific alkaline phosphatase. We have made use of the differential heat-stabilities of these two isoenzymes to study the induction of germ-cell alkaline phosphatase by sodium butyrate and cyclic AMP (cAMP). Sodium butyrate causes a large induction of germ-cell alkaline phosphatase activity (approx. 35-fold after 96 h) after an initial lag period of 12-24 h. We showed that butyrate increases germ-cell alkaline phosphatase mRNA. Dibutyryl cAMP also induces germ cell alkaline phosphatase (approx. 2.5-fold after 96 h). When optimal concentrations of butyrate and dibutyryl cAMP were added simultaneously to cells, they caused a synergistic induction of activity. This suggested that these compounds use separate mechanisms to induce germ-cell alkaline phosphatase activity and that it is the cAMP moiety of dibutyryl cAMP that induces enzyme activity. This was confirmed by the use of two additional cAMP analogues, 8-(4-chlorophenylthio) cAMP and 8-bromo cAMP, and of two compounds, 3-methyl-1-isobutylxanthine and cholera toxin, which raise the endogenous concentration of cAMP. All four compounds caused a 2-fold increase in enzyme activity. Treatment of cells with 8-(4-chlorophenylthio) cAMP, 8-bromo cAMP and cholera toxin increased germ-cell alkaline phosphatase mRNA between 2- and 7-fold. These data suggest that this alkaline phosphatase isoenzyme is regulated at the level of its mRNA by cAMP, in a manner distinct from that of butyrate.

1979 ◽  
Vol 183 (1) ◽  
pp. 73-81 ◽  
Author(s):  
R Felix ◽  
H Fleisch

1. Dichloromethanediphosphonate and to a lesser degree 1-hydroxyethane-1,1-diphosphonate, two compounds characterized by a P-C-P bond, increased the alkaline phosphatase activity of cultured rat calvaria cells up to 30 times in a dose-dependent fashion. 2. Both diphosphonates also slightly inhibited the protein synthesis in these cells. 3. Thymidine, an inhibitor of cell division, did not inhibit the induction of the enzyme, indicating that the increase in enzyme activity was not due to the formation of a specific population of cells with high alkaline phosphatase activity. 4. The effect on alkaline phosphatase was suppressed by the addition of cycloheximide, an inhibitor of protein synthesis. 5. After subculturing the stimulated cells in medium without diphosphonates, the enzyme activity fell almost to the control value. 6. Bovine parathyrin diminished the enzyme activity of the control cells and the cells treated with dichloromethanediphosphonate; however, at high concentration the effect of parathyrin was greater on the diphosphonate-treated cells than on the control cells. 7. The electrophoretic behaviour, heat inactivation, inhibition by bromotetramisole or by phenylalanine, and the Km value of the induced enzyme were identical with that of the control enzyme.


In Vitro ◽  
1979 ◽  
Vol 15 (11) ◽  
pp. 861-864 ◽  
Author(s):  
Walker Wharton ◽  
Cathryn A. Hart ◽  
Barry Goz

1971 ◽  
Vol 17 (3) ◽  
pp. 210-213 ◽  
Author(s):  
Lawrence R DeChatelet ◽  
James V Volk ◽  
Charles E McCall ◽  
M Robert Cooper

Abstract The activity of leukocyte alkaline phosphatase is inhibited by a number of amino acids, most notably cysteine and histidine. The mechanism of this inhibition involves chelation of Zn2+ by the amino acids, as indicated by the complete reversal of the inhibition by added Zn2+. The concentrations of amino acids and Zn2+ required to affect the enzyme activity are such that their interaction might represent an in vivo mechanism for the control of leukocyte alkaline phosphatase activity.


1970 ◽  
Vol 64 (3) ◽  
pp. 398-409 ◽  
Author(s):  
N. Snapir ◽  
M. Perek

ABSTRACT In both young and old laying hens the protein-bound calcium fraction in blood plasma decreased following feed supplementation of 0.05% thyroprotein, whereas the plasma alkaline phosphatase activity significantly increased. The enzyme response was found to be delayed in old as compared to young hens, significantly higher absolute levels being found in the latter. Propylthiouracil treatment caused a marked decrease in protein-bound calcium levels and alkaline phosphatase activity in both young and old hens. The uterine calcium levels and alkaline phosphatase activity in the thyroprotein treated birds did not show any significant differences as compared to the controls, except in the group of old hens receiving the highest dose, in which the calcium level was significantly decreased and the enzyme activity significantly increased. Both propylthiouracil treated groups showed a significant decrease in uterine calcium and alkaline phosphatase activity.


1986 ◽  
Vol 103 (4) ◽  
pp. 1615-1623 ◽  
Author(s):  
B de Bernard ◽  
P Bianco ◽  
E Bonucci ◽  
M Costantini ◽  
G C Lunazzi ◽  
...  

A glycoprotein that exhibits alkaline phosphatase activity and binds Ca2+ with high affinity has been extracted and purified from cartilage matrix vesicles by fast protein liquid chromatography. Antibodies against this glycoprotein were used to analyze its distribution in chondrocytes and in the matrix of calcifying cartilage. Under the light microscope, using immunoperoxidase or immunofluorescence techniques, the glycoprotein is localized in chondrocytes of the resting zone. At this level, the extracellular matrix does not show any reaction. In the cartilage plate, between the proliferating and the hypertrophic region, a weak immune reactivity is seen in the cytoplasm, whereas in the intercolumnar matrix the collagen fibers appear clearly stained. Stained granular structures, distributed with a pattern similar to that of matrix vesicles, are also visible. Calcified matrix is the most stained area. These results were confirmed under the electron microscope using both immunoperoxidase and protein A-gold techniques. In parallel studies, enzyme activity was also analyzed by histochemical methods. Whereas resting cartilage, the intercellular matrix of the resting zone, and calcified matrix do not exhibit any enzyme activity, the zones of maturing and hypertrophic chondrocytes are highly reactive. Some weak reactivity is also shown by chondrocytes of the resting zone. The observation that this glycoprotein (which binds Ca2+ and has alkaline phosphatase activity) is synthesized in chondrocytes and is exported to the extracellular matrix at the time when calcification begins, suggests that it plays a specific role in the process of calcification.


2009 ◽  
Vol 8 (4) ◽  
pp. 28-32 ◽  
Author(s):  
I. V. Zapuskalov ◽  
O. I. Krivosheina ◽  
I. A. Khlusov ◽  
Ya. A. Martusevich ◽  
N. M. Shevtsova ◽  
...  

The culture of stromal stem cells was incubated under constant and dynamic conditions. The incubation period was lasting 48 h. Intracellular enzyme activity of stromal stem cells were carried out with cytochemical methods. Alkaline phosphatase activity was increased under dynamic conditions, differentiation of stromal stem cells being accelerated comparatively steady-state conditions.


1998 ◽  
Vol 41 (2) ◽  
pp. 65-72
Author(s):  
Blanka Pospíšilová ◽  
Dáša Slížová ◽  
Olga Procházková ◽  
Otakar Krs ◽  
Petr Bílek

Activity of alkaline phosphatase in the major salivary glands of male and female mice at various ages of postnatal life, and in females during pregnancy and lactation was studied histochemically. Enzyme activity was not detected on the day of birth, but was found in the terminal tubules of all major salivary glands during the first postnatal week. Alkaline phosphatase activity was increasing gradually with age and a definitive enzymatic pattern was observed by the age of 6 weeks. No difference in enzyme activity was found among the major salivary glands of young adult and old animals. The parenchyma of fully differentiated submandibular glands showed clear sexually dimorphic patterns of alkaline phosphatase activity. During pregnancy, a significant increase of alkaline phosphatase activity was detected in submandibular gland. From gestation day 15 to the end of pregnancy, enzymic pattern of granular convoluted tubules of pregnant females was the same as in the adult males. Histochemical masculinization of the submandibular gland during pregnancy suggests that besides androgens also progesterone exerts masculinization of the murine submandibular salivary gland.


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