The Effectiveness of Specific Collagen Peptides on Osteoarthritis in Dogs-Impact on Metabolic Processes in Canine Chondrocytes

In clinical trials over the past decade, thebeneficial effect of orally administered collagen peptides in osteoarthriticdogs has been clearly demonstrated [1] [2] [3]. Although a statisticallysignificant improvement in the lameness and vitality of dogs in general hasbeen documented, the mode of action of the collagen peptide treatment is stillunder discussion. A previous study [3] indicated that the reduction in lamenessand increased mobility in dogs after collagen peptide treatment were associatedwith a statistically significantly lowered plasma content of MMP-3, which is involvedin collagen degradation. In addition, the content of the MMP-antagonist TIMP-1increased slightly after collagen peptide supplementation, suggesting a directimpact on the cartilage metabolism, particularly on the decrease ofextracellular matrix degradation. Based on these findings, the impact ofspecific collagen peptides (PETA-GILE?) on cartilage metabolism was tested in canine chondrocytes in the current investigation.In addition to the biosynthesis of various matrix molecules (type II collagen,aggrecan and elastin), the RNA profile of inflammatory cytokines and degenerativematrix molecules was investigated. The results showed clearly that thesupplementation of specific collagen peptides reduced catabolic processes, asindicated by a statistically significant decrease in inflammatory cytokines andproteases in canine chondrocytes compared with untreated control experiments.In addition, a statistically significantly enhanced biosynthesis of type IIcollagen, elastin, and aggrecan was observed. Hence, the current data supportsthe suggested anti-inflammatory effect of specific collagen peptides, but alsoclearly demonstrates a pronounced stimulatory impact on matrix moleculesynthesis. A combination of both observed effects might help to explain thepreviously reported clinical improvements after collagen peptidesupplementation. Furthermore, the beneficial effect of the specific collagenpeptides was also confirmed in case reports on osteoarthritic dogs thatdemonstrated decreased lameness and increased vitality in the affected animalsafter PETAGILE treatment.