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Hypothalamic-pituitary-adrenal (HPA) axis. Experiencing an environmental stressor, as perceived by the brain, results in the activation of the HPA axis. The hypothalamus will thus secrete corticotrophin-releasing hormone (CRH). In the anterior lobe of the pituitary gland, CRH stimulates the secretion of adrenocorticotropic hormone (ACTH). The cortex of the adrenal glands will then produce glucocorticoids (cortisol in humans) in response to ACTH. Cortisol will then generate a stress response. 

Hypothalamic-pituitary-adrenal (HPA) axis. Experiencing an environmental stressor, as perceived by the brain, results in the activation of the HPA axis. The hypothalamus will thus secrete corticotrophin-releasing hormone (CRH). In the anterior lobe of the pituitary gland, CRH stimulates the secretion of adrenocorticotropic hormone (ACTH). The cortex of the adrenal glands will then produce glucocorticoids (cortisol in humans) in response to ACTH. Cortisol will then generate a stress response. 

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Introduction Environmental contaminants are ubiquitous. Among the most studied environmental contaminants, lead, mercury, polychlorinated biphenyls and pesticides have been found to impact mental health. In particular, exposure to environmentalcontaminants has been related to executive functions and emotional/behavioural maladjustment in children,...

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... the past three decades, two major factors have been shown to sig- nificantly contribute to the increased inter-individual variability in behav- iour and cognitive performance across development. The first factor relates to genetics 30 and the second relates to stress 30,31 . When individuals are faced with a stressful situation, activation of the hypothalamic- pituitary-adrenal (HPA) axis is induced (Figure 2). Glucocorticoids (GCs; cortisol in humans) are the final secretory products of HPA activation. Given the lipophilic properties of GCs, these adrenal steroid hormones can easily cross the blood-brain barrier and enter the brain, where they can influence brain functions and behaviour by way of binding to different receptor types. Two of the most important brain areas contain- ing GCs receptors are the hippocam- pus and frontal lobes, which are brain structures known to be involved in cognitive function such as memory 32 and emotional/behavioural mal- adjustments, such as impulsivity 33 . Interestingly, deficits in HPA func- tioning has been related to impaired executive functions 34 , emotional/ behavioural adjustments 35 in chil- dren and adolescents and cognitive impairments such as memory com- plaints in the elderly 36 ...

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... The hypothalamic pituitary adrenal (HPA) axis is activated by hypothalamic release of corticotropin-releasing hormone (CRH), which stimulates the secretion of adrenocorticotropin hormone (ACH) from the anterior pituitary gland. ACH then acts on the adrenal cortex to stimulate the release of cortisol (Lanoix and Plusquellec, 2013;Antoun et al., 2017), which is regulated by negative feedback loops to both the anterior pituitary and adrenal cortex. The sympathetic adrenal medullary (SAM) axis is activated by the hypothalamus to stimulate a sympathetic nervous system response, which then stimulates the adrenal medulla to produce epinephrine and norepinephrine (Antoun et al., 2017). ...
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The stress response allows the body to overcome obstacles and prepare for threats, but sustained levels of stress can damage one’s health. Stress has long been measured through physical tests and questionnaires that rely primarily on user-inputted data, which can be subjective and inaccurate. To quantify the amount of stress that the body is experiencing biologically, analytical detection of biomarkers associated with the stress response recently have been developed. Novel stress sensing devices focus on cortisol sweat sensing as a part of wearable, flexible devices. These devices promise a real-time, continuous collection of stress data that can be used in clinical diagnoses or for personal stress monitoring and mediation.
... The ability to activate the appropriate neuroendocrine and physiologic responses to a stressor is crucial to maintaining the homeostasis of the adrenocortical system (Hontela et al., 1995). Recent evidence suggests that exposure to environmental contaminants alters the adrenal response to stress (Plusquellec and Lanoix, 2013). A longitudinal study following 120 children from their birth to late childhood has demonstrated that prenatal and postnatal Pb exposures increase adrenocortical reactivity to an acute stress (Gump et al., 2008). ...
Article
Exposure to environmental toxicants can have deleterious effects on the development of physical, cognitive, and mental health. Extensive laboratory and clinical studies have demonstrated how the developing brain is uniquely sensitive to toxic agents. This chapter focuses on the main neurologic impairments linked to prenatal and postnatal exposure to lead, methylmercury, and polychlorinated biphenyls, three legacy environmental contaminants whose neurotoxic effects have been extensively studied with respect to cognitive and behavioral development. The main cognitive, emotion regulation, sensory, and motor impairments in association with these contaminants are briefly reviewed, including the underlying neural mechanisms such as neuropathologic damages, brain neurotransmission, and endocrine system alterations. The use of neuroimaging as a novel tool to better understand how the brain is affected by exposure to environmental contaminants is also discussed.
... In humans, elevated cortisol and aldosterone levels are associated with low birth weight (Martinez-Aguayo et al., 2011). Lanoix and Plusquellec (2013) suggested that a disruption of the stress system could explain an association between environmental contaminants and mental health, especially in children and elderly people. ...
Article
Persistent organic pollutants (POPs) are toxic substances, highly resistant to environmental degradation, which can bio-accumulate and have long-range atmospheric transport potential (UNEP 2001). The majority of studies on endocrine disruption have focused on interferences on the sexual steroid hormones and so have overlooked disruption to glucocorticoid hormones. Here the endocrine disrupting potential of individual POPs and their mixtures has been investigated in vitro to identify any disruption to glucocorticoid nuclear receptor transcriptional activity. POP mixtures were screened for glucocorticoid receptor (GR) translocation using a GR redistribution assay (RA) on a CellInsightTM NXT High Content Screening (HCS) platform. A mammalian reporter gene assay (RGA) was then used to assess the individual POPs, and their mixtures, for effects on glucocorticoid nuclear receptor transactivation. POP mixtures did not induce GR translocation in the GR RA or produce an agonist response in the GR RGA. However, in the antagonist test, in the presence of cortisol, an individual POP, p,p’-dichlorodiphenyldichloroethylene (p,p’-DDE), was found to decrease glucocorticoid nuclear receptor transcriptional activity to 72.5% (in comparison to the positive cortisol control). Enhanced nuclear transcriptional activity, in the presence of cortisol, was evident for the two lowest concentrations of perfluorooctanesulfonic acid (PFOS) (0.0147 mg/ml and 0.0294 mg/ml), the two highest concentrations of perfluorodecanoic acid (PFDA) (0.0025 mg/ml and 0.005 mg/ml) and the highest concentration of 2,2’,4,4’-tetrabromodiphenyl ether (BDE-47) (0.0000858 mg/ml). It is important to gain a better understanding of how POPs can interact with GRs as the disruption of glucocorticoid action is thought to contribute to complex diseases.
... These data suggested that TDBP-TAZTO induced cognition impairment and depression-like responses, at least in part, by upregulating ACTH and CORT levels. The published data also reported that the environmental organic contaminants including POPs can impair the stress system and activate the HPA axis [38]. ...
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Tris-(2,3-dibromopropyl) isocyanurate (TDBP-TAZTO), an emerging brominated flame retardant, possesses the characteristics of candidate persistent organic pollutants and has displayed toxicity to fish and rodents. TDBP-TAZTO can pass through the blood brain barrier and accumulate in brain. However, the neurotoxicity of TDBP-TAZTO has not yet studied in rodents. We hypothesize that TDBP-TAZTO could induce the neurotoxicity in rat hippocampal neurons. The male adult rats were exposed to TDBP-TAZTO of 5 and 50 mg/kg by gavage, daily for 6 months. TDBP-TAZTO resulted in cognitive impairment and depression-like behaviors, which may be related with TDBP-TAZTO-induced hypothalamic-pituitary-adrenal axis hyperactivation, upregulation of inflammatory and oxidative stress markers, overexpression of pro-apoptotic proteins, downexpression of neurogenesis-related proteins in hippocampus, and hippocampal neurons damage in DG, CA1 and CA3 areas. Our findings suggested that TDBP-TAZTO induces significant hippocampal neurotoxicity, which provokes cognitive impairment and depression-like behaviors in adult rats. Therefore, this research will contribute to evaluate the neurotoxic effects of TDBP-TAZTO in human.
Chapter
This chapter examines how our mental, physical, and relational health are tied to the health of the ecosystem. Many of the common presenting problems we see in therapy (e.g., alienation, depression, anxiety, a sense of meaninglessness, and relational conflict) are tied to three critical and often unrecognized factors: (1) the impact of nature-deficit; (2) an addiction to technology and other secondary sources; and (3) exposure to environmental toxicity. Examples are provided to help illuminate how many of the most common mental and physical health symptoms we see in therapy are linked to these three factors. The chapter outlines how therapists can assess and intervene to address common problems in ways that address the underlying influence of these three factors.
Conference Paper
This study aimed to determine species identities of processed sea cucumbers from selected Malaysian markets i.e. Kuantan, Pahang (East Coast region of Peninsular Malaysia) and Langkawi Island, Kedah (the Northern region) in the forms of dried (seven specimens) and frozen (12 specimens) products. Most of the products were not labelled with species details. Fresh samples that were morphologically identified as Stichopus horrens (gamat species– three specimens) and Holothuria leucospilota (timun laut species– three specimens) from Pangkor Island, Perak were also included as reference samples. Partial sequences of protein-coding cytochrome c oxidase I (COI) mitochondrial DNA (mtDNA) gene were acquired, and subsequent analyses using Basic Local Alignment Search Tool (BLAST) and phylogenetic analyses were done. Phylogenetic analyses were incorporated to understand genetic relationship of the sea cucumber species and to compare the sequences from processed sea cucumber with the species and source details of the products. Phylogenetic analyses of 25 partial sequences using five main methods namely Neighbour-Joining (NJ), Maximum Likelihood (ML), Minimum Evolution (ME), Unweighted Pair Group Method with Arithmetic Mean (UPGMA) and Maximum Parsimony (MP) showed the presence of two main families of sea cucumbers: Stichopodidae (gamat family) and Holothuriidae (timun laut family), thus supporting the BLAST results. Specimens of S. horrens and S. herrmanni were the two gamat species that clustered under family Stichopodidae. A specimen of H. leucospilota, the most dominant species from family Holothuriidae in Malaysia, was also recorded. Further studies with more samples and mtDNA genes e.g. non-protein-coding 16S mtDNA gene need to be done to get a better view and verification. The outcomes of this study will provide better information on the level of species substitution and product mislabelling issues of processed sea cucumbers in Malaysian markets which will subsequently assists the enforcement agencies to monitor and overcome the issues through mtDNA sequencing technique. Keywords: Processed sea cucumbers, mtDNA sequencing, COI gene, BLAST, phylogenetic trees.