Abstract
The present investigation was undertaken to compare the effects of β-alanyl-L-histidinato zinc (AHZ) and its zinc-chelating ligands on bone metabolism in tissue culture. Calvaria were removed from 3-week-old male rats and cultured for up to 72h in Dulbecco's modified eagle medium containing zinc sulfate, AHZ, di (N-acetyl-β-alanyl-L-histidinato) zinc (AAHZ), and di (histidino) zinc (HZ). The bone calcium content and alkaline phosphatase activity were significantly increased in the presence of AHZ or AAHZ (10-8-10-5 M). Those increases were seen at 10-7 to 10-5 M zinc sulfate and HZ. The bone deoxyribonucleic acid (DNA) content was significantly increased by AHZ or AAHZ with 10-7 to 10-5 M, while 10-7 M zinc sulfate and HZ had no effect. Thus, AHZ and AAHZ had more potent effect than that of zinc sulfate and HZ. The effect of AHZ, AAHZ and HZ (10-5 M) increasing bone alkaline phosphatase activity was abolished by the presence of 10-4 M dipicolinate, a chelator of zinc. Moreover, the effect of these zinc compounds on bone metabolic indices was not seen in the presence of 10-6 M cycloheximide. The present results suggest that the effect of AHZ and AAHZ on bone metabolism is more potent than that of zinc sulfate and HZ.
