C-type natriuretic peptide (CNP) is known to promote chondrocyte proliferation and bone formation; however, CNP’s extremely short half-life necessitates continuous intravascular administration to achieve bone-lengthening effects. Vosoritide, a CNP analog designed for resistance to neutral endopeptidase, allows for once-daily administration. Nonetheless, it distributes systemically rather than localizing to target tissues, which may result in adverse effects such as hypotension. To enhance local drug delivery and therapeutic efficacy, we developed a potentially novel synthetic protein by fusing a collagen-binding domain (CBD) to CNP, termed CBD-CNP. This fusion protein exhibited stability under heat conditions and retained the collagen-binding ability and bioactivity as CNP. CBD-CNP localized to articular cartilage in fetal murine tibiae and promoted bone elongation. Spatial transcriptomic analysis revealed that the upregulation of chondromodulin expression may contribute to its therapeutic effects. Treatment of CBD-CNP mixed with collagen powder to a fracture site of a mouse model increased bone mineral content and bone volume compared with CNP-22. Intraarticular injection of CBD-CNP to a mouse model of knee osteoarthritis suppressed subchondral bone thickening. By addressing the limitations of CNP’s rapid degeneration, CBD-CNP leverages its collagen-binding capacity to achieve targeted, sustained delivery in collagen-rich tissues, offering a promising strategy for enhancing chondrogenesis and osteogenesis.

Sudden cardiac events in young athletes are a major concern in the field of sports cardiology. Although coronary artery anomalies remain a major cause of cardiac events in young athletes, only a few cases have been diagnosed prior to critical events. Here, we present the case of a previously asymptomatic young male runner who experienced sudden cardiac arrest at the end of a marathon. The patient immediately received cardiopulmonary resuscitation from a bystander and was transported to an emergency hospital. As his electrocardiogram showed ventricular fibrillation, he was treated with electric shock, and his rhythm was successfully converted to a normal sinus rhythm. Following successful resuscitation, the patient was diagnosed with an anomalous origin of the right coronary artery from the left sinus of Valsalva with an intramural course. The patient underwent coronary artery bypass using the right internal thoracic artery. Fifteen years later, the coronary bypass was found to be blocked, but the patient was asymptomatic. However, an exercise electrocardiogram revealed ST-segment elevation in the inferior leads. The patient then underwent an unroofing procedure. He has remained asymptomatic without complications for two years after the second surgery.