Leptin promoted ADAMTS-4 and ADAMTS-5 expression.

<p>(<b>A</b>) The effect of leptin on ADAMTS-4 and ADAMTS-5 mRNA expression assessed using Real-time RT-PCR. For the dose-dependent studies, NP cells were treated with either medium only or varying concentrations of leptin (1–1000 ng/ml) for 24 h. For the time-depent studies, NP cells were treated with either medium only or leptin (10 ng/ml) for varing time intervals (0–72 h). (<b>B</b>) The effect of leptin on ADAMTS-4 and ADAMTS-5 protein expression was detected with western blotting ananlysis using GAPDH as an internal control. Error bars represent standard deviration. The medium was changed every day. *p<0.05, ** p<0.01, and ***p<0.001.