Effects of extracellular calcium concentration on the glutamate release by bioactive glass (BG60S) preincubated osteoblasts.
Glutamate released by osteoblasts sharing similarities with its role in neuronal transmission is a very new scientific concept which actually changed the understanding of bone physiology. Since glutamate release is a calcium (Ca(2+))-dependent process and considering that we have previously demonstrated that the dissolution of bioactive glass with 60% of silicon (BG60S) can alter osteoblast Ca(2+)-signaling machinery, we investigated whether BG60S induces glutamate secretion in osteoblasts and whether it requires an increase in intracellular Ca(2+). Here we showed that the extracellular Ca(2+) increase due to BG60S dissolution leads to an intracellular Ca(2+) increase in the osteoblast, through the activation of an inositol 1,4,5-triphosphate receptor (InsP(3)R) and a ryanodine receptor (RyR). Additionally, we also demonstrated that glutamate released by osteoblasts can be profoundly altered by BG60S. The modulation of osteoblast glutamate released by the extracellular Ca(2+) concentration opens a new window in the field of tissue engineering, since many biomaterials used for bone repair are able to increase the extracellular Ca(2+) concentration due to their dissolution products.
Valerio
P
P
Department of Physiology and Biophysics, Federal University of Minas Gerais, Brazil. patricia.valerio@terra.com.br
Pereira
M M
MM
Goes
A M
AM
Leite
M Fatima
MF
D000818:Animals; D000831:Animals, Newborn; D001672:Biocompatible Materials / Q000494:pharmacology; D001842:Bone and Bones / Q000378:metabolism; D002118:Calcium / Q000378:metabolism* / Q000494:pharmacology; D002136:Calcium, Dietary / Q000494:pharmacology; D005110:Extracellular Space / Q000378:metabolism; D005898:Glass; D018698:Glutamic Acid / Q000494:pharmacology*; D015544:Inositol 1,4,5-Trisphosphate / Q000494:pharmacology; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D019837:Ryanodine Receptor Calcium Release Channel / Q000378:metabolism* / Q000494:pharmacology; D012825:Silicon / Q000494:pharmacology; D023822:Tissue Engineering
D001672:Biocompatible Materials; D002136:Calcium, Dietary; D019837:Ryanodine Receptor Calcium Release Channel; D018698:Glutamic Acid; D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium; D012825:Silicon