Alleviation of osteoarthritis by calycosin-7-O-beta-D-glucopyranoside (CG) isolated from Astragali radix (AR) in rabbit osteoarthritis (OA) model.
OBJECTIVE
This work was undertaken to assess the protective effect of an isoflavonoid, calycosin-7-O-beta-D-glucopyranoside (CG), isolated from Astragali radix (AR) on the pathogenesis of osteoarthritis (OA)-like lesion in a rabbit model.


METHODS
Nine rabbits underwent an anterior cruciate ligament and menisectomy transection (ACLMT) of the rear knee joints to induce OA-like lesion. They were randomly divided into three groups (n=6/group): a negative control group treated with 200 microl of 0.5% (v/v) dimethyl sulfoxide (DMSO), a positive control group treated with 200 microl of 100 microM piroxicam, and a test group treated with 100 microg/500 microl of CG, where the test agents were administered by injection once a week for 4 weeks starting from the third week. Rabbits were then sacrificed to observe the progression of OA-like lesion. The synovial fluid was analyzed for the amounts of total proteins, glycosaminoglycans (GAG) and prostaglandin E(2) (PGE(2)). In addition, histopathologic analyses were performed on the OA-like articular cartilage with or without therapeutic treatments.


RESULTS
The total synovial fluid volume (P<0.05) was most strikingly reduced by the treatment with CG. Moreover, the CG treatment also significantly alleviated the OA-induced accumulation of prostaglandin (PG) (P<0.001) and total proteins (P<0.001) in the synovial fluid. The histopathologic analyses revealed that the CG treatment reduced the severity of the OA-like structural damages in the cartilage. However, the level of PGE(2), a pathologic inflammatory molecule, was not diminished by CG or piroxicam.


CONCLUSIONS
These results indicate that the isoflavonoid CG isolated from AR significantly alleviated the pathologic changes in the OA-like rabbit knee joints. This suggests that CG from AR could be a promising treatment for the therapy of OA.
Choi
S I
SI
Department of Biological Engineering, Inha University, Incheon 402-751, South Korea.
Heo
T R
TR
Min
B-H
BH
Cui
J H
JH
Choi
B H
BH
Park
S R
SR
D000818:Animals; D016118:Anterior Cruciate Ligament / Q000601:surgery; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D027883:Astragalus Plant; D002358:Cartilage, Articular / Q000187:drug effects* / Q000378:metabolism; D004195:Disease Models, Animal; D005960:Glucosides / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use*; D006025:Glycosaminoglycans / Q000378:metabolism; D007529:Isoflavones / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use*; D008592:Menisci, Tibial / Q000601:surgery; D010003:Osteoarthritis / Q000188:drug therapy*; D010894:Piroxicam / Q000627:therapeutic use; D011453:Prostaglandins / Q000378:metabolism*; D011506:Proteins / Q000032:analysis; D011817:Rabbits; D011897:Random Allocation; D013582:Synovial Fluid / Q000737:chemistry* / Q000378:metabolism
D000894:Anti-Inflammatory Agents, Non-Steroidal; D005960:Glucosides; D006025:Glycosaminoglycans; D007529:Isoflavones; D011453:Prostaglandins; D011506:Proteins; C488311:calycosin-7-O-glucopyranoside; D010894:Piroxicam