The Effects of Undenatured Type II Collagen on Inflammatory Mediators and Oxidative Stress in an Osteoarthritis Rat Model

Abstract

Abstract The present study aimed to investigate the effects of undenatured type II collagen on monosodium iodoacetate-induced osteoarthritis (OA) rats, and elucidate its underlying anti-inflammatory and antioxidant mechanisms. Several parameters such as body mass, pain threshold of knee joint, supporting force of the left and right feet, serum levels of inflammation mediators and cartilage metabolic marker, malondialdehyde (MDA) content, superoxide dismutase (SOD) activity and knee joint histopathology were measured. The results demonstrated that undenatured type II collagen enhanced the pain threshold of knee joint and reduced the difference in supporting force between the left and right feet. Moreover, undenatured type II collagen increased serum TGF-β concentration and decreased the serum levels of TNF-α, MMP-13 and CTX-II in OA rats. In addition, decreased serum MDA content and increased serum SOD activity were found in undenatured type II collagen treatment group when compared to those in model group. Histopathological data indicated that undenatured type II collagen exhibited protective effects on both synovial and cartilaginous tissues in OA rats. Taken altogether, the findings of this study reveal that undenatured type II collagen can relieve and prevent OA symptoms by regulating inflammatory mediators and oxidative stress. Additionally, this collagen helps to reduce knee OA pain and maintain normal joint function.