Cell-free treatment reduces brain damage and improves recovery after stroke in mice

Ischemic stroke can result in lasting neurological damage due to oxidative stress, neuroinflammation, neuronal death and disruption of neural connectivity. Current interventions provide limited protection against delayed neuronal injury, which hinders functional recovery. Professor Won-Jae Kim and his team at Chonnam National University in South Korea explored whether the extracellular secretome of human dental pulp stem cells (hDPSC) could improve recovery after stroke.

The hDPSC secretome contains bioactive factors such as extracellular vesicles, growth factors, antioxidant enzymes and immunomodulatory proteins. Unlike cell transplantation, which faces challenges like poor cell survival and immune rejection, secretome-based therapy offers a safer, supportive treatment. The study identified 299 proteins uniquely present in the hDPSC secretome, many of which were associated with antioxidant defense, neuroprotection, angiogenesis, apoptosis regulation and oxidative stress resistance.

The researchers found that the hDPSC secretome improved microglial cell viability, reduced oxidative stress and restored mitochondrial function in the laboratory. In a mouse model of ischemic stroke, the hDPSC secretome significantly reduced stroke-inflicted damage, minimized oxidative stress and inflammation, and promoted vascular and synaptic recovery.

Behavioral assessments revealed substantial improvements in physical balance, motor coordination and sensorimotor responses, as well as cognitive domains such as spatial learning, working memory and associative memory. Moreover, the treatment reduced post-stroke anxiety. If validated in clinical trials, this stem cell-derived secretome therapy could provide a novel, safe and effective approach to limiting brain damage and actively repairing neural networks in stroke patients, potentially extending its benefits to other neurological diseases like Alzheimer's and Parkinson's.