adult neurogenesis

Air pollution exposure is among the most prevalent reasons for environmentally-induced oxidative stress and inflammation, both of which are implicated in the central nervous system (CNS) diseases. The CNS has emerged as an important target for adverse health effects of exposure to air pollutants, where it can cause neurological and neurodevelopmental disorders. Air pollution includes various components of gases, particulate matter (PM), ultrafine particulate (UFPs), metals, and organic compounds. An important source of PM and UFPM in the ambient air is associated with air pollution-related trafficking, and primarily diesel exhaust particles (DEPs). Controlled animal studies and epidemiological studies show that exposure to air pollution, and in particular urban air pollution or DEPs, may lead to neurotoxicity. In specific, exposure to air pollutants as an important factor may be in neurodevelopmental disorders (eg Autism) and neurological disorders (eg.., Alzheimer’s Disease (AD)). The most noticeable effects of exposure to air pollutants in animals and humans are oxidative stress and neurodegeneration. Studies in rats exposed to DEPs showed microglial activity, increased lipid peroxidation, and neuronal accumulation in various areas of the brain, especially the olfactory bulb (OB) and the hippocampus (HI). Disorders of adult neurogenesis were also found. In most cases, the effects of DEP are more pronounced in male mice, probably due to lower antioxidant capacity due to less expression of paraoxonase 2.

Background: The study of new neuron formation in the adult brain has sparked controversy and ignited interest among scientists in recent times, these include its occurrence and location in the adult human brain, functional significance, variation in study methods, translation from animal model to human, and ethical challenges involving neural stem cell research. Aim: To provide a comprehensive understanding of adult neurogenesis, functional significance, and challenges and explore the latest advances in the study of adult neurogenesis. Methodology: An extensive and systematic search of electronic databases (Medline, Scopus, Web of Science) was conducted using keywords related to adult neurogenesis and techniques involved in its study. Results: The mechanism of adult neurogenesis was found to occur in specific brain regions such as the subgranular zone of the dentate gyrus and subventricular zone of the lateral ventricle. Adult neurogenesis is vital neural plasticity, providing a potential mechanism for the brain to adapt and reorganize in response to environmental cues and experiences. Cutting-edge research and sophisticated imaging techniques, such as two-photon microscopy, MRI, optogenetic, and stem-cell-based therapies have provided deeper insight into the study of adult neurogenesis. Conclusion: The study of neurogenesis is important for understanding nervous system development, physiology, pathology, and exploring neuroplasticity. Its advancement is challenged by some ethical concerns regarding embryonic, pluripotent stem cells, and the need for safe, and noninvasive study methods. Although recent breakthroughs in neuroimaging, microscopic techniques, and genetic tools are aiding real-time study of adult neurogenesis.