Epigenetic changes after prolonged exposure to alkenylbenzenes – An important signature of potential toxicological effects

Abstract Pesticides are used in agriculture and in domestic pest control. Dichlorvos, an organophosphate, is a predominant pesticide used in domestic insect control in developing countries. Acute and prolonged exposure may lead to death, genotoxic, neurological, reproductive, carcinogenic, immunological, hepatic, renal, respiratory, metabolic, dermal and other systemic effects. Its toxicity is due to the ability of the compound to inhibit acetyl cholinesterase at cholinergic junction of the nervous system. This study is a review of the toxicological effects of dichlorvos in a public health perspective.

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TOXICOLOGICAL EFFECTS OF PROLONGED EXPOSURE TO y-HEXACHLOROCYCLOH EXANE IN CHICKENS

Assiut Veterinary Medical Journal ◽

10.21608/avmj.2000.180451 ◽

2000 ◽

Vol 42.2 (84) ◽

pp. 60-76

Keyword(s):

Prolonged Exposure ◽

Toxicological Effects

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Toxicological effects of prolonged exposure of soot-polluted air on some haematological and biochemical parameters of residents of Port Harcourt

International Journal of Research in Medical Sciences ◽

10.18203/2320-6012.ijrms20191082 ◽

2019 ◽

Vol 7 (4) ◽

pp. 1063

Author(s):

Kemzi Elechi-Amadi ◽

Batubo Nimisoere Peace ◽

Boma Harris Opusunju ◽

Andrew Jiala

Keyword(s):

Total Cholesterol ◽

Prolonged Exposure ◽

Low Density Lipoprotein ◽

Venous Blood ◽

Density Lipoprotein ◽

Hdl Cholesterol ◽

Polluted Environment ◽

Toxicological Effects ◽

Port Harcourt ◽

Apparently Healthy

Background: Soot is a by-product of incomplete combustion of carbon derived from substances that contains carbon like hydrocarbons, which is associated with various human diseases. The objectives of the studies are to evaluate the toxicological effects of prolonged exposure of soot polluted air on some haematological and biochemical parameters.Methods: One hundred apparently healthy residents of Port Harcourt residing in soot polluted environment for a minimum of 12 months and one hundred apparently healthy subjects residing in non-soot polluted environment outside Port Harcourt were recruited for this study. 5ml of venous blood was collected from each subject after 10hours of overnight fast to estimate the PCV, Hb, RBC, WBC, lymphocytes, neutrophils, bicarbonate, total cholesterol, triglyceride, low density lipoprotein and high density lipoprotein using automated autoanalyzer.Results: There was a statistically significant decrease in the PCV, Hb, RBC and increase in WBC, Lymphocytes and neutrophils. There was also a significant increase in the bicarbonate, total cholesterol and LDL with a decrease in HDL cholesterol as compared to the control.Conclusions: It is concluded that prolong exposure to soot polluted air is harmful and associated with deterioration of haematological parameters and also induces oxidative stress and lipid peroxidation which may increase morbidity and mortality.

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Gene Expression and Epigenetic Changes in Mice Following Inhalation of Copper(II) Oxide Nanoparticles

Nanomaterials ◽

10.3390/nano10030550 ◽

2020 ◽

Vol 10 (3) ◽

pp. 550 ◽

Cited By ~ 4

Author(s):

Pavel Rossner ◽

Kristyna Vrbova ◽

Andrea Rossnerova ◽

Tana Zavodna ◽

Alena Milcova ◽

...

Keyword(s):

Dna Methylation ◽

Immune Response ◽

Prolonged Exposure ◽

Global Dna Methylation ◽

Oxide Nanoparticles ◽

Biological Processes ◽

Epigenetic Changes ◽

Transcriptomic Response ◽

Collagen Formation ◽

Cuo Nps

We investigated the transcriptomic response and epigenetic changes in the lungs of mice exposed to inhalation of copper(II) oxide nanoparticles (CuO NPs) (8 × 105 NPs/m3) for periods of 3 days, 2 weeks, 6 weeks, and 3 months. A whole genome transcriptome and miRNA analysis was performed using next generation sequencing. Global DNA methylation was assessed by ELISA. The inhalation resulted in the deregulation of mRNA transcripts: we detected 170, 590, 534, and 1551 differentially expressed transcripts after 3 days, 2 weeks, 6 weeks, and 3 months of inhalation, respectively. Biological processes and pathways affected by inhalation, differed between 3 days exposure (collagen formation) and longer treatments (immune response). Periods of two weeks exposure further induced apoptotic processes, 6 weeks of inhalation affected the cell cycle, and 3 months of treatment impacted the processes related to cell adhesion. The expression of miRNA was not affected by 3 days of inhalation. Prolonged exposure periods modified miRNA levels, although the numbers were relatively low (17, 18, and 38 miRNAs, for periods of 2 weeks, 6 weeks, and 3 months, respectively). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analysis based on miRNA–mRNA interactions, revealed the deregulation of processes implicated in the immune response and carcinogenesis. Global DNA methylation was not significantly affected in any of the exposure periods. In summary, the inhalation of CuO NPs impacted on both mRNA and miRNA expression. A significant transcriptomic response was already observed after 3 days of exposure. The affected biological processes and pathways indicated the negative impacts on the immune system and potential role in carcinogenesis.

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Longitudinal genome-wide methylation study of PTSD treatment using prolonged exposure and hydrocortisone

Translational Psychiatry ◽

10.1038/s41398-021-01513-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ruoting Yang ◽

Changxin Xu ◽

Linda M. Bierer ◽

Janine D. Flory ◽

Aarti Gautam ◽

...

Keyword(s):

Prolonged Exposure ◽

Fear Learning ◽

Body Region ◽

Startle Reaction ◽

Epigenetic Changes ◽

Symptom Change ◽

Post Traumatic Stress ◽

Genome Wide ◽

Potential Applications ◽

Future Utility

AbstractEpigenetic changes are currently invoked as explanations for both the chronicity and tenacity of post-traumatic stress disorder (PTSD), a heterogeneous condition showing varying, sometimes idiosyncratic responses to treatment. This study evaluated epigenetic markers in the context of a randomized clinical trial of PTSD patients undergoing prolonged-exposure psychotherapy with and without a hydrocortisone augmentation prior to each session. The purpose of the longitudinal epigenome-wide analyses was to identify predictors of recovery (from pretreatment data) or markers associated with symptom change (based on differences between pre- and post-therapy epigenetic changes). The results of these analyses identified the CREB–BDNF signaling pathway, previously linked to startle reaction and fear learning and memory processes, as a convergent marker predicting both symptom change and severity. Several previous-reported resilience markers were also identified (FKBP5, NR3C1, SDK1, and MAD1L1) to associate with PTSD recovery in this study. Especially, the methylation levels of FKBP5 in the gene body region decreased significantly as CAPS score decreased in responders, while no changes occurred in nonresponders. These biomarkers may have future utility in understanding clinical recovery in PTSD and potential applications in predicting treatment effects.

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Epigenetic Changes Associated With Exposure to Glyphosate-Based Herbicides in Mammals

Frontiers in Endocrinology ◽

10.3389/fendo.2021.671991 ◽

2021 ◽

Vol 12 ◽

Author(s):

María Florencia Rossetti ◽

Guillermina Canesini ◽

Virginia Lorenz ◽

María Mercedes Milesi ◽

Jorgelina Varayoud ◽

...

Keyword(s):

Endocrine System ◽

Chemical Compounds ◽

Methylphosphonic Acid ◽

Amino Acid Derivative ◽

Epigenetic Changes ◽

Environmental Matrices ◽

Main Metabolite ◽

Toxicological Effects ◽

Non Coding Rnas ◽

Intense Debate

Glyphosate is a phosphonomethyl amino acid derivative present in a number of non-selective and systemic herbicides. During the last years the use of glyphosate-based herbicide (GBH) has been increasing exponentially around the world, including Argentina. This fact added to the detection of glyphosate, and its main metabolite, amino methylphosphonic acid (AMPA), in environmental matrices such as soil, sediments, and food, has generated great concern about its risks for humans, animals, and environment. During the last years, there were controversy and intense debate regarding the toxicological effects of these compounds associated with the endocrine system, cancer, reproduction, and development. The mechanisms of action of GBH and their metabolites are still under investigation, although recent findings have shown that they could comprise epigenetic modifications. These are reversible mechanisms linked to tissue-specific silencing of gene expression, genomic imprinting, and tumor growth. Particularly, glyphosate, GBH, and AMPA have been reported to produce changes in global DNA methylation, methylation of specific genes, histone modification, and differential expression of non-coding RNAs in human cells and rodents. Importantly, the epigenome could be heritable and could lead to disease long after the exposure has ended. This mini-review summarizes the epigenetic changes produced by glyphosate, GBHs, and AMPA in humans and rodents and proposes it as a potential mechanism of action through which these chemical compounds could alter body functions.

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Microplastics in the Environment: Intake through the Food Web, Human Exposure and Toxicological Effects

Toxics ◽

10.3390/toxics9090224 ◽

2021 ◽

Vol 9 (9) ◽

pp. 224

Author(s):

Concetta Pironti ◽

Maria Ricciardi ◽

Oriana Motta ◽

Ylenia Miele ◽

Antonio Proto ◽

...

Keyword(s):

Food Web ◽

Health Risks ◽

Human Exposure ◽

Prolonged Exposure ◽

Aquatic Organisms ◽

Potential Health ◽

Toxicological Effects ◽

Toxicological Studies ◽

High Concentrations ◽

Short Time

Recently, studies on microplastics (MPs) have increased rapidly due to the growing awareness of the potential health risks related to their occurrence. The first part of this review is devoted to MP occurrence, distribution, and quantification. MPs can be transferred from the environment to humans mainly through inhalation, secondly from ingestion, and, to a lesser extent, through dermal contact. As regards food web contamination, we discuss the microplastic presence not only in the most investigated sources, such as seafood, drinking water, and salts, but also in other foods such as honey, sugar, milk, fruit, and meat (chickens, cows, and pigs). All literature data suggest not-negligible human exposure to MPs through the above-mentioned routes. Consequently, several research efforts have been devoted to assessing potential human health risks. Initially, toxicological studies were conducted with aquatic organisms and then with experimental mammal animal models and human cell cultures. In the latter case, toxicological effects were observed at high concentrations of MPs (polystyrene is the most common MP benchmark) for a short time. Further studies must be performed to assess the real consequences of MP contamination at low concentrations and prolonged exposure.

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