Antler extracts stimulate chondrocyte proliferation and possess potent anti-oxidative, anti-inflammatory, and immune-modulatory properties.

The Sika deer antler is well known for its unique ability to regenerate repeatedly and grow rapidly. Furthermore, it is a precious traditional Chinese medicine and has been widely used for more than 20 centuries. The major bioactive components within the antlers are water-soluble proteins, polypeptides, and free amino acids. Many studies have shown that water-soluble antler extracts play pivotal roles in wound healing, immune system modulation, anti-oxidation, and anti-inflammation. However, the exact effects on chondrocytes are still largely unknown. In this study, we prepared fresh, aqueous extracts from growing deer antlers in a rapid growth stage. We isolated the chondrocytes from neonatal mouse rib cartilage and investigated the effects of antler extracts on chondrocyte viability. We also used the RNA-Seq method to analyze the gene expression pattern under antler extract treatment. We demonstrated that fresh extracts from Sika deer antlers in a rapid growth stage significantly promoted chondrocyte viability and kept chondrocytes proliferating continuously, while blocking maturation and further differentiation. Additionally, our results indicated that antler extracts might serve as a potent anti-oxidant, anti-inflammatory agent, and immune modulator to boost the abilities of chondrocytes against oxidative, inflammatory, and immune stresses. Thus, this study has greatly deepened our current knowledge of the molecular control of antler extracts on chondrocytes. It has also shed light on possible new strategies to further prevent and treat diseases of cartilage and other related diseases.