Objective: To examine whether phosphocitrate (PC) will block nitric oxide-i
nduced calcification of cartilage or chondrocyte-derived apoptotic bodies.
Design: Articular cartilage vesicles (ACV) or apoptotic bodies (AB) were is
olated from untreated or 1 mM sodium nitroprusside (SNP) treated porcine ca
rtilage slices. Mineralization of ACV, AB, control untreated and SNP-treate
d cartilage were done in the presence or absence of PC (1 mM) +/- ATP (1 mM
).
Results: PC [1 mM] blocked both the ATP-dependent and -independent minerali
zation in ACV and AB, untreated and SNP treated cartilage. Moreover, PC had
no effect on NTPPPH activity in either ACV or AB fraction in the presence
or absence of ATP suggesting that PC did not block the mineralization throu
gh the inhibition of NTPPPH activity.
Conclusions: PC inhibits nitric oxide-induced calcification of cartilage an
d cartilage-derived apoptotic bodies.