OBJECTIVETo study the effects of sand treatment on cysteine aspartate-specific proteinase-3 (Caspase-3), B-cell leukemia-lymphoma-2 (Bcl-2), Bcl-2-associated X protein gene (Bax) in the articular cartilage of rabbit knee osteoarthritis (OA), and the apoptotic protein expression, thus providing theoretical evidence for sand treatment in Uyghur medicine.

METHODSThe OA animal model was established by fixing right hind limbs with gypsum in 22 New Zealand rabbits. Of them, 2 original model rabbits were taken as the control group, while the rest 20 were randomly divided into a free running group and a sand treatment group, 10 in each group. The healthy side of the free running group was taken as the normal control group. The sand treatment was given to those in the sand treatment group for 20 days. The expressions of Caspase-3, Bcl-2, and Bax in the cartilage cells of rabbit knee joint were measured by immunohistochemical assay. The cell apoptosis of chondrocytes was detected using terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL).

RESULTSCompared with the normal control group, the positive cell number, the optical density (OD), the protein expressions of Caspase-3, Bax, and TUNEL were higher in the free running group and the sand treatment group (P < 0.01). Besides, they were obviously higher in the free running group than in the sand treatment group (P < 0.01). The positive cell number of Bcl-2 and OD value in the free running group and the sand treatment group were both lower than those of the normal control group (P < 0.01). The positive cell number was obviously higher in the sand treatment group than in the free running group (P < 0.01).

CONCLUSIONSand treatment could inhibit the expressions of Caspase-3, Bax/Bcl-2, and TUNEL in the articular cartilage of rabbits' knee OA, which might be partial mechanisms for anti-inflammation of sand treatment.