Antioxidant Carbon Dot of Selenomethionine Alleviates Oxidative Stress in Intervertebral Disc Degeneration

Intervertebral disc degeneration (IVDD) is a progressive degenerative disorder of the spine characterized by oxidative stress and cellular dysfunction. Current clinical treatments for IVDD include surgical procedures, such as discectomy and spinal fusion, as well as pharmacological therapies using analgesics and anti-inflammatory agents. However, these strategies primarily offer symptomatic relief and do not address the underlying causes of IVDD. Targeting oxidative stress has emerged as a promising therapeutic approach, yet its effectiveness remains limited. To overcome this limitation, an antioxidant carbon dot of selenomethionine (Se-Met-CD) is developed for efficient IVDD therapy. Se-Met-CD effectively scavenges excess reactive oxygen species (ROS), alleviates oxidative stress, and restores intracellular redox homeostasis in nucleus pulposus cells. Se-Met-CD exhibits an antioxidant capacity 3.1 times that of its precursor, Se-Met, when compared at the same concentration. In hydrogen peroxide (H₂O₂)-treated nucleus pulposus cells, Se-Met-CD significantly reduces intracellular ROS levels to 17.7% of those in untreated control cells. In a puncture-induced IVDD rat model, Se-Met-CD demonstrates remarkable therapeutic efficacy by significantly attenuating disc degeneration, reflected in lower Pfirrmann and histological scores. These results underscore the potential of Se-Met-CD to treat IVDD by scavenging ROS, restoring antioxidant balance, and modulating the local microenvironments.