Antioxidant effects of adipose derived stem cells conditioned media against high glucose-induced injuries in cultured of C28I2 chondrocytes

Osteoarthritis (OA) is the most common form of arthritis characterized by progressive loss of articular cartilage, causing pain and loss of articular function. High glucose is a crucial inflammatory factor playing a pivotal role in the pathogenesis of OA that induces ROS production. Since most of the current therapies for OA are short-term benefits, hence, there is high demand for finding novel therapeutic agents for OA treatment. Recent studies have demonstrated that mesenchymal stem cells secrete important therapeutic factors that protect chondrocytes. In the current study, we investigated the protective potential of Adipose-derived stem cell conditioned medium (CM-ADSC) as an alternative to cell therapy in high glucose-mediated oxidative stress in C28I2 human chondrocytes.

This experimental study was performed in the Department of Pharmacology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran from May 2018 to August 2020. Adipose-derived stem cells were cultured until they reached 90% confluence then washed with PBS and cultured in a FBS-free medium for 48 hours. The conditioned medium was collected and centrifuged. The protective effect of the concentration of conditioned medium on high glucose (75mM)-induced oxidative stress in C28I2 cell viability was evaluated by WST-1 assay. Total RNA was isolated from the treated and untreated cells with TRIzol reagent. The mRNA expression of antioxidant enzymes including, glutathione S-transferase-P1 (GSTP1), catalase (CAT), and superoxide dismutase1 (SOD1) was evaluated by reverse transcription-polymerase chain reaction in treatment and non-treatment groups.

Adipose-derived stem cell conditioned medium pretreatment remarkably protected C28I2 cells against high glucose. The expression of mRNA of CAT, GSTP1, and SOD1 significantly increased following treatment with the conditioned medium (50%) for 24 hours in high glucose-exposed cells as compared to the control.

Present study indicates that the Adipose-derived stem cell conditioned medium can reduce oxidative stress. It seems that the conditioned medium may protect cartilage in the progression of osteoarthritis.