Apoptosis of growth plate chondrocytes occurs through a mitochondrial pathway.
OBJECTIVE
To determine the role of mitochondria in chondrocyte apoptosis induced by inorganic phosphate (Pi).


METHODS
Chondrocytes isolated from the growth plates of chick embryo tibia were treated with Pi in serum-free media; chondrocyte viability, mitochondrial membrane potential, cytochrome c release from mitochondria, caspase 3 activity, endonuclease activity, and DNA fragmentation were investigated.


RESULTS
Exposure to Pi for 24 hours induced apoptosis in growth plate chondrocytes through a pathway that involved loss of mitochondrial function, release of cytochrome c into the cytoplasm, increases in caspase 3 and endonuclease activities, and fragmentation of DNA.


CONCLUSIONS
This study suggests that mitochondria are important players in Pi-induced apoptosis.
Teixeira
Cristina C
CC
Department of Orthodontics and Department of Basic Sciences, New York University College of Dentistry, New York, NY 10010, USA. cristina.teixeira@nyu.edu
Costas
Aida P Padron
AP
Nemelivsky
Yelena
Y
D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D015153:Blotting, Western; D020169:Caspases / Q000378:metabolism; D002642:Chick Embryo; D019902:Chondrocytes / Q000187:drug effects* / Q000201:enzymology; D045304:Cytochromes c / Q000502:physiology; D004720:Endonucleases / Q000378:metabolism; D004789:Enzyme Activation; D006132:Growth Plate / Q000166:cytology; D008564:Membrane Potentials / Q000187:drug effects; D051336:Mitochondrial Membranes / Q000187:drug effects*; D010710:Phosphates / Q000633:toxicity*; D013977:Tibia
D010710:Phosphates; D045304:Cytochromes c; D004720:Endonucleases; D020169:Caspases