The hallmarks of environmental issues and the brain

Abstract

BACKGROUND AND AIM: The aim of this presentation is to discuss the knowledge regarding the impact of the hallmark environmental insults on the brain. Air pollution, noise, heat, light at night, industrial chemicals, and lack of green space have been associated with the impairment of brain development and function and higher risk of neurological diseases and neurodegeneration. METHODS: Several hallmarks (oxidative stress, methylation, endocrine disruption, mitochondrial disfunction, telomers, intravesicular cells, miRNA, microbiome, autonomous nervous system irritation) have been suggested to underline these relationships via direct and indirect pathways. The nervous system itself controls the body's physiological processes and as such could impair the cardiovascular, metabolic/endocrine, and respiratory systems, among others. RESULTS:The efforts in understanding the intermediate role of the cellular hallmarks between the exposure and the brain effects is a path to establish causal relationships. For instance, a key development is to discover the windows of greatest sensitivity of structural and functional brain changes to air pollution. The brain has the widest vulnerable window among all systems. Prenatal exposures may have more severe consequences for the brain because brain structures are forming during this period and may cause permanent brain injury and predict cognitive impairment later in life. Supporting the importance of the prenatal period, mice experiments consistently reported that prenatal exposure to fine PM and diesel exhaust could induce inflammatory reactions and structural changes in several brain regions related with the myelination process which has been replicated in humans, in part, through impairing placental function via PM deposition in the placenta or indirectly via several of the hallmarks in peripheral blood and in the placenta itself. CONCLUSIONS:Hallmarks could be relevant for informing about the persistence or tracking of the effects until later life. It is important to simultaneously study the effect of these hallmarks together on the brain in relation to the exposome. KEYWORDS: omics technologies,Neurologic and mental health outcomes, air pollution, chemical exposues, climate