Traumatic brain injury: basic cellular mechanisms and new approaches to therapy

Relevance. Traumatic brain injury (TBI) is a serious medical problem and one of the leading causes of disability and mortality among military personnel and civilians. It is known that about 1.5 million people in the world die from TBI every year, while about 2.5–3 million lose work capacity. In Russia, one million people are diagnosed with TBI every year, among which one in five gets group I or II disability. Despite significant efforts in research, effective TBI treatment methods are still limited, as TBI leads to a wide range of pathological changes in brain tissues. Primary brain damage is an acute and irreversible mechanical damage to the parenchyma of the nervous tissue. Among subsequent secondary processes are excitotoxicity, mitochondrial dysfunction, oxidative stress, axon degeneration, and neuroinflammation. These processes are often long and can take from several days to several years. Recent advances in cell therapy are opening up new perspectives for the treatment of this condition. The current review examines the main cellular mechanisms of TBI acute and chronic phases, as well as the treatment prospects for the use of stem cells for. Analysis of recent studies on the use of cell therapy in TBI is presented. Various types of stem cells such as neural stem cells, mesenchymal stromal cells and others are considered in the context of their potential to repair damaged brain tissues. Special attention is paid to the cells action mechanisms in the regeneration process, including their effect on inflammation, neurogenesis, and synaptic plasticity. The issue of using paracrine factors secreted by stem cells as a potential drug for traumatic brain injuries treatment is addressed. Conclusion. Сell therapy, as well as the use of products secreted by cells, is one of the new and promising ways of treating TBI.