Topical Collection "Xenobiotics in Developmental Neurotoxicity"

Editor

Collection Editor
Prof. David R. Wallace

Department of Pharmacology & Physiology, Oklahoma State University Center for Health Sciences, 1111 West 17th Street, Tulsa, OK 74107-1898, USA
Website | E-Mail
Interests: heavy metals and development of cancer; cadmium as an underlying factor in obesity and diabetes; heavy metals and changes in neural function altering addiction; mechanisms of metal and pesticide cellular actions

Topical Collection Information

Dear Colleagues,

The role of xenobiotics in the development of the brain is a rapidly expanding field. A xenobiotic agent is a foreign substance found in a biological organism that would not be normally found in that organism, or found at much higher concentrations than expected. These agents can cover chemical pollutants, drugs, or other biological agents, such as viral particles. There have been significant advances in neuroscience research over the last two decades. The developing brain is extremely sensitive to insult from exogenous xenobiotics. This sensitivity is not confined to in utero exposure, but also throughout infant, toddler, and pre-teen adolescent neurodevelopment. Work in developmental neurotoxicology (DNT) has lagged. Reasons for this delay include; (1) difficulty in finding appropriate model systems, (2) lack of existing toxicology data on many of the chemicals that are commercially available, and (3) relative lack of information regarding mixtures of various chemicals that are commercially available. Most xenobiotics can be categorized based on their physiological/chemical agent. These categories include antioxidants, carcinogens, drugs (prescription/over-the-counter/illegal), environmental pollutants, food additives, hydrocarbons, and pesticides. Of the tens of thousands of compounds, only about 100 compounds have minimal or incomplete evidence of DNT, which includes some pesticides (organophosphates), prescription drugs and a variety of other chemicals. It is clear that additional research is needed to identify appropriate model systems to study DNT effects that will improve the translation from alternative to human model systems. Also, additional work is needed to identify and develop accurate biomarkers that will signal exposure to DNT compounds early in the exposure period, facilitating medical intervention. The purpose of this Topical Collection is to provide a forum to develop a compendium of work spanning a variety of topics to further our understanding of DNT.

Prof. David R. Wallace
Collection Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the collection website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Toxics is an international peer-reviewed open access quarterly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 350 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • xenobiotics
  • biomarkers
  • animal models
  • in vitro testing
  • neurodevelopment
  • risk assessment

Published Papers (3 papers)

2017

Jump to: 2016

Open AccessReview EDCs Mixtures: A Stealthy Hazard for Human Health?
Received: 12 December 2016 / Revised: 23 January 2017 / Accepted: 25 January 2017 / Published: 7 February 2017
Cited by 9 | PDF Full-text (269 KB) | HTML Full-text | XML Full-text
Abstract
Endocrine disrupting chemicals (EDCs) are exogenous chemicals that may occur naturally (e.g., phytoestrogens), while others are industrial substances and plasticizers commonly utilized worldwide to which human exposure, particularly at low-doses, is omnipresent, persistent and occurs in complex mixtures. EDCs can interfere with/or mimic
[...] Read more.
Endocrine disrupting chemicals (EDCs) are exogenous chemicals that may occur naturally (e.g., phytoestrogens), while others are industrial substances and plasticizers commonly utilized worldwide to which human exposure, particularly at low-doses, is omnipresent, persistent and occurs in complex mixtures. EDCs can interfere with/or mimic estrogenic hormones and, consequently, can simultaneously trigger diverse signaling pathways which result in diverse and divergent biological responses. Additionally, EDCs can also bioaccumulate in lipid compartments of the organism forming a mixed “body burden” of contaminants. Although the independent action of chemicals has been considered the main principle in EDCs mixture toxicity, recent studies have demonstrated that numerous effects cannot be predicted when analyzing single compounds independently. Co-exposure to these agents, particularly in critical windows of exposure, may induce hazardous health effects potentially associated with a complex “body burden” of different origins. Here, we performed an exhaustive review of the available literature regarding EDCs mixtures exposure, toxicity mechanisms and effects, particularly at the most vulnerable human life stages. Although the assessment of potential risks to human health due to exposure to EDCs mixtures is a major topic for consumer safety, information regarding effective mixtures effects is still scarce. Full article
Figures

Graphical abstract

2016

Jump to: 2017

Open AccessCommunication Hair Microelement Profile as a Prognostic Tool in Parkinson’s Disease
Received: 17 August 2016 / Revised: 8 November 2016 / Accepted: 10 November 2016 / Published: 16 November 2016
PDF Full-text (964 KB) | HTML Full-text | XML Full-text
Abstract
Changes in the homeostasis of metals and microelements have been demonstrated in Parkinson’s disease, whose etiology includes both a genetic and environmental basis. We studied the difference of microelements in the hair of Parkinson’s disease subjects (n = 46) compared with healthy
[...] Read more.
Changes in the homeostasis of metals and microelements have been demonstrated in Parkinson’s disease, whose etiology includes both a genetic and environmental basis. We studied the difference of microelements in the hair of Parkinson’s disease subjects (n = 46) compared with healthy controls (n = 24). Hair was chosen as a representative matrix to measure microelements, since it is a vehicle of substance excretion from the human body and it allows for long-term evaluation of metal exposure. An inductively coupled plasma mass spectrometry (ICP-MS) analysis of hair collected from 24 Parkinson’s patients compared with their healthy relatives used as controls shows a significant decrease in Ca (U = 166, p = 0.012),), Mg (U = 187, p = 0.037), and Sr (U = 183, p = 0.030). Cd and Ca/Mg were decreased, and Cu was increased, in patients with respect to their healthy related controls at the limit of significance (p = 0.0501). Principal Component Analysis (PCA) of these microelements in hair shows a clustering into two groups according to gender, disease severity according to the Hoehn–Yahr scale, and pharmacological therapy. This pilot study represents a starting point for future investigations where a larger group of subjects will be involved to define other microelements useful when screening for early biomarkers of Parkinson’s disease. Full article
Figures

Figure 1

Open AccessReview The Synapse as a Central Target for Neurodevelopmental Susceptibility to Pesticides
Received: 30 June 2016 / Revised: 7 August 2016 / Accepted: 17 August 2016 / Published: 26 August 2016
Cited by 3 | PDF Full-text (570 KB) | HTML Full-text | XML Full-text
Abstract
The developmental period of the nervous system is carefully orchestrated and highly vulnerable to alterations. One crucial factor of a properly-functioning nervous system is the synapse, as synaptic signaling is critical for the formation and maturation of neural circuits. Studies show that genetic
[...] Read more.
The developmental period of the nervous system is carefully orchestrated and highly vulnerable to alterations. One crucial factor of a properly-functioning nervous system is the synapse, as synaptic signaling is critical for the formation and maturation of neural circuits. Studies show that genetic and environmental impacts can affect diverse components of synaptic function. Importantly, synaptic dysfunction is known to be associated with neurologic and psychiatric disorders, as well as more subtle cognitive, psychomotor, and sensory defects. Given the importance of the synapse in numerous domains, we wanted to delineate the effects of pesticide exposure on synaptic function. In this review, we summarize current epidemiologic and molecular studies that demonstrate organochlorine, organophosphate, and pyrethroid pesticide exposures target the developing synapse. We postulate that the synapse plays a central role in synaptic vulnerability to pesticide exposure during neurodevelopment, and the synapse is a worthy candidate for investigating more subtle effects of chronic pesticide exposure in future studies. Full article
Figures

Figure 1

Back to Top