Procyanidins and Their Therapeutic Potential Against Bone/Cartilage Diseases.

Bone and cartilage diseases impair labor capacity and cause significant economic losses. As a dietary flavonoid, procyanidins have a wide range of sources and possess antioxidant, anti-inflammatory, and anti-tumor properties. They are used to treat various diseases such as tumors, cardiovascular diseases, and Alzheimer's disease. Recent studies have shown that procyanidins inhibit osteoclast activation, ameliorate the inflammatory environment, protect cartilage from damage by inflammatory factors, and reduce bone loss. Larger polymer procyanidins extracted from plants are oligomers that cannot be utilized by the human body. Polymeric procyanidins rely on chemical- or enzyme-assisted methods to depolymerize into oligomeric compounds. This article discusses the role of procyanidins in bone and cartilage diseases such as osteoporosis, arthritis, and fractures; summarizes the basic process of procyanidin extraction; analyzes the advantages and disadvantages of commonly used depolymerization methods; and emphasizes the potential of new biomaterials and targeted drug delivery methods to improve the bioavailability and biological activity of procyanidins.