Cartilage and bone biological markers in the synovial fluid of osteoarthritic patients after hyaluronan injections in the knee.
OBJECTIVE
To evaluate synovial fluid levels of cartilage and bone biological markers after repetitive intra-articular injections of sodium hyaluronate (HA) in knee osteoarthritis (OA) patients.


METHODS
Twenty patients with knee OA were evaluated before and after 5 weekly injections of HA. To study cartilage and bone biological markers, synovial fluid and urine samples were collected simultaneously with the first (FI=week 0) and before the last injection (LI=week 4) of HA. Not commercially available markers (cartilage oligomeric matrix protein (COMP), proteoglycan monomers and cyanogen bromide peptide 11 of the type II collagen chains (alpha (II) CA11B)) were determined by an indirect inhibition ELISA developed and standardized in our laboratory.


RESULTS
We found a significant reduction in levels of proteoglycan monomers (30+/-16 vs. 22+/-10 microg/ml, p<0.05), an increase in COMP concentration (2.9+/-0.9 vs. 3.6+/-0.9 microg/ml, p<0.05) and osteocalcin (BGP) levels (8.7+/-8 vs. 11.9+/-9 ng/ml, p<0.05). No significant changes were observed in the levels of alpha (II)CB11B), metalloproteinase-1 (MMP-1) or pyridinium cross-link/creatinine (Pyr/Cr).


CONCLUSIONS
HA could elicit an indirect response on the cartilage and bone metabolism due to the increased overuse of the joint caused by the analgesic effect of HA. However, a direct HA action on the metabolism of chondrocytes must not be ruled out.
Herrero-Beaumont
G
G
Inflammation Research Unit, Fundación Jiménez Díaz, Avda. Reyes Católicos 2, 28040 Madrid, Spain. gherrero@fjd.es
Guerrero
R
R
Sánchez-Pernaute
O
O
Acebes
C
C
Palacios
I
I
Mas
S
S
Rodriguez
I
I
Egido
J
J
Vivanco
F
F
D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis; D001842:Bone and Bones / Q000378:metabolism*; D002356:Cartilage / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006801:Humans; D006820:Hyaluronic Acid / Q000008:administration & dosage*; D007270:Injections, Intra-Articular / Q000379:methods; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000188:drug therapy* / Q000378:metabolism*; D015675:Osteocalcin / Q000032:analysis / Q000187:drug effects; D011509:Proteoglycans / Q000032:analysis / Q000187:drug effects; D013582:Synovial Fluid / Q000187:drug effects / Q000378:metabolism*
D015415:Biomarkers; D011509:Proteoglycans; D015675:Osteocalcin; D006820:Hyaluronic Acid