Carboxymethylated chitosan protects rat chondrocytes from NO-induced apoptosis via inhibition of the p38/MAPK signaling pathway

Abstract

In the present study, the effect of carboxymethylated chitosan (CMCS) on nitric oxide (NO)‑induced apoptosis, and activation of the p38/MAPK signaling pathway in chondrocytes were investigated. Cartilage was isolated from the knee joints of Sprague‑Dawley rats, and was used to establish cultured primary chondrocytes. The chondrocytes were incubated with the NO donor, sodium nitroprusside (SNP), to induce apoptosis, and were treated with CMCS and the p38 inhibitor, SB203580. Cell viability was assessed using a Cell Counting Kit‑8 assay. Apoptosis of the chondrocytes was detected using Annexin V‑fluorescein isothiocyanate/propidium iodide staining. The activation of p38 was detected using Western blot analysis, and caspase‑3 activity was detected using a caspase‑3 detection kit. The results indicated that, in chondrocytes treated with SNP, the optical density values of the experimental groups were significantly lower, compared with the control group (P<0.05). The exposure of the cells to CMCS significantly prevented apoptosis (P<0.05), and a dose‑dependent effect was demonstrated using fluorescence‑activated cell sorting analysis (P<0.05). Examination of the expression and activity of p38 and caspase‑3, respectively, showed that SNP increased the expression of p38 and activity of caspase‑3, and this trend was reversed following the addition of CMCS and SB203580. Taken together, these findings indicated that CMCS prevented NO‑induced apoptosis of chondrocytes via inhibition of the p38/mitogen‑activated protein kinase signaling pathway in vitro.

Controlled Release of Interleukin-1 Receptor Antagonist from Hyaluronic Acid-Chitosan Microspheres Attenuates Interleukin-1β-Induced Inflammation and Apoptosis in Chondrocytes

“…The present study showed that CS or HA-CS slightly but not significantly changed the gene and protein levels of Bcl-2, Bax, and caspase-3. Our data agree with the previous reports [38, 39]. In addition, the expression of Bcl-2 was significantly increased in the CS-IL-1Ra and HA-CS-IL-1Ra groups, while the expressions of Bax and caspase-3 were decreased at the transcriptional and translational levels compared with those in the control group, with HA-CS-IL-1Ra having slightly more potent effect than CS-IL-1Ra.…”

Chitosan oligosaccharides inhibit IL-1β-induced chondrocyte apoptosis via the P38 MAPK signaling pathway

“…Thus, we can inhibit the NO production to protect mitochondrial functions and can decrease the chondrocyte apoptosis rate. Moreover much evidence suggests that the mediators including hyper production of NO have been proposed to be necessary for activation of the p38/MAPK signaling pathway in chondrocytes [32,33]. In our study, COS can suppress the mRNA expression levels of iNOS.…”

Mitochondrial dependent pathway is involved in the protective effects of carboxymethylated chitosan on nitric oxide-induced apoptosis in chondrocytes

“…CMCS has been widely studied in OA related diseases in recent years in vivo and in vitro in recent days [15][16][17]. We have also used CMCS in cultured chondrocytes and found CMCS also has the inhibitory effect on NO-induced apoptosis in cultured chondrocytes [18,19].…”

“…The isolation and identification of primary chondrocytes from SD rats according to the previously described [18,19]. The experimental protocols were approved by Animal Ethics Committee of Wuhan University (Wuhan, China).…”

“…In this present study, different concentrations (0.5, 1.0, 2.0, 3.0 and 4.0 mM) of sodium nitroprusside (SNP), NO donor, was used to build up the chondrocyte apoptotic model. Our previous results showed the maximum apoptotic response was observed at 3 mM SNP treated chondrocyte [18]. To investigate the protective roles of CMCS on cytotoxicity and apoptosis, chondrocytes pretreated by different doses of SNP followed by addition of CMCS (50, 100 and 200 μg/ml) for further experiments.…”