Effect of pterostilbene on oxidative stress induced apoptosis in chondrocytes / 中国组织工程研究

ABSTRACT

BACKGROUND: A variety of antioxidants exhibit anti-arthritis effects by inhibiting the production of inflammatory factors. Pterostilbene is a powerful natural antioxidant; however, there is no report on its effect against oxidative stress in chondrocytes. OBJECTIVE: To investigate the effect of pterostilbene on oxidative stress induced apoptosis in human chondrocytes METHODS: Normal human articular chondrocytes were cultured in medium containing different concentrations of pterostilbene (7.8-32 000 μg/L) for 24 continuous hours to determine the optimal concentration of pterostilbene. Normal human articular chondrocytes cultured in vitro were randomized into control group, pterostilbene group (treatment with 125 μg/L pterostilbene), hydrogen p eroxide (H2O2) group (treatment with 0.2 mmol/L H2O2), and H2O2 plus pterostilbene group (pretreatment with 125 μg/L pterostilbene followed by continuous treatment in the medium containing 125 μg/L pterostilbene and 0.2 mmol/L H2O2). After treating for 24 hours, the cell proliferation rate was detected by MTT experiment, the cell morphology and number by hematoxylin-eosin staining, the cell activity was measured by FDA/PI staining, and the changes of proteoglycan content were observed by saffron O staining. The expression of chondrogenesis marker genes aggrecan and type II collagenase 1 was detected by RT-PCR. An approval for the study protocol was validated by the Ethic Committee of the First Affiliated Hospital of Guangxi Medical University with an approval No. 20180500 8. RESULTS AND CONCLUSION: The results of MTT assay showed that pterostilbene could significantly promote chondrocyte growth at 15.6-250 μg/L, especially at 125 μg/L. The results of hematoxylin-eosin staining and FDA/PI staining further showed that pterostilbene could inhibit H2O2-induced chondrocyte apoptosis, promote chondrocyte proliferation, and increase cell viability. The results of saffron O staining showed that pterostilbene promoted the secretion of proteoglycan by chondrocytes and inhibited the adverse effects of H2O2 on chondrocytes. The results of RT-PCR further revealed that pterostilbene could promote the expression of aggrecan and type II collagenase 1 genes in chondrocytes damaged by oxidative stress and improve the chondrocyte differentiation function. In conclusion, pterostilbene can promote chondrocyte proliferation and inhibit human articular chondrocyte apoptosis caused by oxidative stress.