Neurotoxicity of Endocrine Disruptors: Possible Involvement in Brain Development and Neurodegeneration

Abstract

Environmental chemicals that act as endocrine disruptors do not appear to pose a risk to human reproduction; however, their effects on the central nervous systems are less well understood. Animal studies suggested that maternal exposure to endocrine-disrupting chemicals (EDC) produced changes in rearing behavior, locomotion, anxiety, and learning/memory in offspring, as well as neuronal abnormalities. Some investigations suggested that EDC exert effects on central monoaminergic neurons, especially dopaminergic neurons. Our data demonstrated that EDC attenuate the development of dopaminergic neurons, which might be involved in developmental disorders. Perinatal exposure to EDC might affect neuronal plasticity in the hippocampus, thereby potentially modulating neuronal development, leading to impaired cognitive and memory functions. Endocrine disruptors also attenuate gender differences in brain development. For example, the locus ceruleus is larger in female rats than in males, but treatments with bisphenol-A (BPA) enlarge this region in males. Some reports indicated that EDC induce hypothyroidism, which might be evidenced as abnormal brain development. Endocrine disruptors might also affect mature neurons, resulting in neurodegenerative disorders such as Parkinson's disease. The current review focused on alterations in the brain induced by EDC, specifically on the possible involvement of EDC in brain development and neurodegeneration.

Orally administered <i>p</i>-nitrotoluene causes hyperactivity, concomitant with gliosis and impairment of tyrosine hydroxylase immunoreactivity in the rat substantia nigra

“…Although an emerging body of evidence suggests that an endocrine disruptor such as bisphenol A exerts its effects on the central nervous system (CNS) in rodents (Masuo and Ishido, 2011), there is little information about the effects of p-nitrotoluene on the CNS. Previously, we demonstrated that intracisternal administration of p-nitrotoluene causes hyperactivity in the Wistar male rat (Ishido et al, 2004), following the protocol by Shaywitz et al (1976).…”

Bisphenol A delays the perinatal chloride shift in cortical neurons by epigenetic effects on the Kcc2 promoter

“…Animal studies suggest that in utero and early postnatal exposure to BPA produce a broad range of adverse effects (10)(11)(12). Historically, endocrine-reproductive and immune function-related abnormalities were documented first, and impaired brain development and behavior have been linked to BPA exposure more recently (13)(14)(15).…”

The Neuroendocrine and Neurodevelopmental Effects of Endocrine Disrupting Chemicals

“…Değişen bu fizyolojik durum kendini bilişsel fonksiyonda gerileme, stres yanı-tında değişim, sosyoseksüel ve ebeveyn davranışla-rında bozulmalar şeklinde gösterebilmektedir. 15,16 Nöroendokrin bozucu kimyasal maddelere bağlı etkiler ve bu konuda yürütülen hayvan çalışmaları farklı başlıklar altında aşağıda sunulmuştur.…”

“…Turkiye Klinikleri J Neur 2018;13(1): [7][8][9][10][11][12][13][14][15][16][17][18][19] lar, DEHP maruziyetine erkek ve dişilerin yaş ve doz-yanıt eğrisi açısından farklı yanıtlar verdiğini göstermektedir. 19 Hipotalamustaki anteroventral periventrikü-ler çekirdek (AVPV) ve cinsel dimorfik çekirdek-mediyal preoptik alan [sexually dimorphic nucleus of the preoptic area (SDN-POA)] cinsiyete özgü üreme fizyolojisi ve davranışlarda rol oynamakta ve her iki bölge de östradiole bağlı olarak cinsiyete bağlı gelişim göstermektedir.…”