Biomarkers for traumatic brain injury: a short review.

Cellular response to TBI is a mixture of excitotoxicity, neuroinflammation, and cell death. Biomarkers that can track these lesions and inflammatory processes are being explored for their potential to provide objective measures in the evaluation of TBI, from prehospital care to rehabilitation. By understanding the pathways involved, we could be able to improve diagnostic accuracy, guide management, and prevent long-term disability. We listed some of the recent advances in this translational, intriguing, fast-growing field. Although the knowledge gaps are still significant, some markers are showing promising results and could be helping patients in the near future.

Myelin, aging, and physical exercise.

Myelin sheath is a structure in neurons fabricated by oligodendrocytes and Schwann cells responsible for increasing the efficiency of neural synapsis, impulse transmission, and providing metabolic support to the axon. They present morpho-functional changes during health aging as deformities of the sheath and its fragmentation, causing an increased load on microglial phagocytosis, with Alzheimer's disease aggravating. Physical exercise has been studied as a possible protective agent for the nervous system, offering benefits to neuroplasticity. In this regard, studies in animal models for Alzheimer's and depression reported the efficiency of physical exercise in protecting against myelin degeneration. A reduction of myelin damage during aging has also been observed in healthy humans. Physical activity promotes oligodendrocyte proliferation and myelin preservation during old age, although some controversies remain. In this review, we will address how effective physical exercise can be as a protective agent of the myelin sheath against the effects of aging in physiological and pathological conditions.