Inhibition of bone resorption in vitro by serine-esterase inhibitors.

Abstract

The effect of two synthetic serine esterase inhibitors, N-alpha-dansyl(p-guanidino)phenylalaninepiperidine hydrochloride (I 2581) and D-phenylalanyl-L-prolyl-L-arginine chloromethyl ketone (D-Phe-Pro-Arg-CH2Cl), on bone resorption in organ cultured mouse calvaria from neonatal mice has been examined. Mineral mobilization was assessed by analyzing the release of 45Ca, stable calcium (Ca2+) and inorganic phosphate (Pi). Organic matrix degradation was studied by analyzing the release of 3H from [3H]proline-labelled bones, and by quantifying the amounts of hydroxyproline in bone after culture. It was found that I 2581, at and above 30 mumol/l, dose-dependently inhibited 45Ca release induced by thrombin, parathyroid hormone (PTH), prostaglandin E2 and 1-alpha-hydroxyvitamin D-3. I 2581 (50 mumol/l) inhibited PTH-stimulated release of 3H from [3H]proline-labelled bones, and this effect was reversible after withdrawal of I 2581. I 2581 (50 mumol/l) inhibited the release of Ca2+, Pi, beta-glucuronidase and beta-N-acetylglucosaminidase in bones stimulated by PTH and 1-alpha-hydroxyvitamin D-3, without affecting the release of lactate dehydrogenase. In parallel, I 2581 decreased PTH and 1-alpha-hydroxyvitamin D-3 induced reduction of hydroxyproline levels in bones after culture. I 2581 (50 mumol/l) did not affect the basal release of 45Ca, Ca2+, beta-glucuronidase and beta-N-acetylglucosaminidase, nor the basal amounts of hydroxyproline in bones after culture. D-Phe-Pro-Arg-CH2Cl (100 mumol/l) significantly inhibited PTH- and PGE2-induced release of 45Ca without affecting basal release of radioactive calcium. These data indicate that activation of serine proteinase(s) may be a necessary step in the mechanism of action of several stimulators of bone resorption.

• Authors: U H Lerner, G T Gustafson
• Journal: Biochimica et biophysica acta (Biochim Biophys Acta) Vol. 964 Issue 2 Pg. 129-36 (Feb 17 1988) ISSN: 0006-3002 [Print] Netherlands
• PMID: 3342254 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Amino Acid Chloromethyl Ketones
• Hydroxycholecalciferols
• Parathyroid Hormone
• Phosphates
• Piperidines
• Phenylalanine
• N-dansyl-(1,4-guanidino)phenylalanine piperdide
• L-Lactate Dehydrogenase
• Esterases
• serine esterase
• Glucuronidase
• Acetylglucosaminidase
• phenylalanyl-prolyl-arginine-chloromethyl ketone
• Hydroxyproline
• Calcium
• alfacalcidol

Topics

• Acetylglucosaminidase (metabolism)
• Amino Acid Chloromethyl Ketones (pharmacology)
• Animals
• Animals, Newborn
• Bone Resorption (drug effects)
• Bone and Bones (drug effects, metabolism)
• Calcium (metabolism)
• Esterases (antagonists & inhibitors)
• Glucuronidase (metabolism)
• Hydroxycholecalciferols (pharmacology)
• Hydroxyproline (metabolism)
• L-Lactate Dehydrogenase (metabolism)
• Mice
• Organ Culture Techniques
• Parathyroid Hormone (pharmacology)
• Phenylalanine (analogs & derivatives, pharmacology)
• Phosphates (metabolism)
• Piperidines (pharmacology)