Effects of endocrine active substances in wildlife species: Genetic, biochemical, and physiological factors in variable susceptibility to endocrine disruptors

2003 ◽  
Vol 75 (11-12) ◽  
pp. 2335-2341 ◽  
Author(s):  
Shin'ichiro Kawai ◽  
M. Kobayashi ◽  
Hideo Kaneko
Keyword(s):  
Endocrine System ◽  
Aquatic Organisms ◽  
Xenobiotic Metabolism ◽  
Environmental Chemicals ◽  
Ah Receptor ◽  
Blood Levels ◽  
Aromatase Activity ◽  
Physiological Factors ◽  
Wildlife Species ◽  
Active Substances

Responses to endocrine active substances (EASs) in animals are various, and differences between the responses among individuals, populations and species are well known. These differences are observed not only in EASs but in most environmental chemicals including synthetic and naturally occurring ones. The basic differences in sensitivity to EASs are attributed to that of affinity or specificity of the receptors to EASs at the cellular level. Although the nucleotide sequences encoding for estrogen receptor proteins have been documented in several species and the functions of the receptors are the same, the ability to bind the natural hormones and the estrogenic xenobiotics is not necessarily identical. The reproductive endocrine system is basically common among vertebrates, but chemical types of hormones, physiological roles of hormones and the basal blood levels of hormones differ among each species, especially in sex steroids. These differences cause various types of responses and sensitivity to EASs among animal species. Xenobiotic metabolism is important for the genetical, biochemical and physiological factors concerning the influence of EASs. Some EASs directly inhibit cytochrome P450 (CYP) activity as was reported in tributyltin that inhibits CYP19 (aromatase) activity causing imposex in neogastropods. Some organochlorines including dioxins stimulate aryl hydrocarbon (Ah) receptor-mediated xenobiotic metabolism, and result in the metabolic disruption of steroid hormones such as estrogen as were reported in eggshell thinning in birds of prey and uterus occlusion in seals. CYP activity greatly differs among wildlife species in both terrestrial and aquatic organisms, and these differences are significantly responsible for the multiple effects or toxicity of EASs. Sex and age differences also cause different responses to EASs and are largely due to the differences in xenobiotic metabolizing activities.

scholarly journals Risk Assessment of Malakite with the Active Substances Dithianon and Pyrimenthanil

2019 ◽  
pp. 312-314
Author(s):  
Torsten Källqvist ◽  
Merete Grung ◽  
Katrine Borgå ◽  
Hubert Dirven ◽  
Ole Martin Eklo ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Surface Waters ◽  
Plant Protection ◽  
Aquatic Organisms ◽  
Toxicity Tests ◽  
Concentration Addition ◽  
Active Ingredients ◽  
Active Substances ◽  
Assessment Factor

The plant protection product Malakite (BAS 669 01 F), containing the active substances dithianon and pyrimethanil, is a fungicide against scab in pome fruits. Products containing these active plant protection substances are approved in Norway, but not with both substances in the same product. The Swedish Chemicals Agency (KemI) has as zonal Rapporteur Member State (zRMS) of the Northern Zone evaluated the product Malakite and decided on non-approval due to the observation of unacceptable effects in exposed birds, aquatic organisms, non-target arthropods and earthworms. On request from The Norwegian Food Safety Authority, the VKM Panel on Plant Protection Products has discussed the available data and the report prepared by KemI, and has concluded as follows on the questions raised: On the refinement of DT50 in long term risk assessment for birds: It is the view of the VKM panel that the refinement is not acceptable because the analysis using first order kinetics seems not in line with a realistic and sufficiently conservative approach for the data provided. Furthermore, field studies from more sites are required. On the long term cumulative effects of the active substances on birds: VKM shares the view of KemI, that the combined sub-lethal and reproduction effects should be assessed because the mode of action of the two ingredients has only been shown in fungi, and since the mechanisms in birds could be different. On the reduction of assessment factor for fish: VKM opposes to the reduction of assessment factor for dithianon in fish because the data from acute toxicity tests cannot be extrapolated to chronic toxicity, and because the factor should reflect not only the variation in interspecies sensitivity, but also the uncertainty involved in extrapolation from laboratory tests to the field situation. On the choice of end point in risk assessment for fish: The VKM panel considers the NOEC of dithianon for fish determined from the study at pH 7.9 not to be adequate for the more acidic Norwegian surface waters, and recommends using the data from the test performed at pH 6.5. On the formulation studies for aquatic organisms: It is the opinion of the VKM panel that the formulation studies may be used together with corresponding studies with the active ingredients as long as the studies compared are performed and evaluated according to the same principles. However, VKM notes that the formulation tests as well as the tests of the active ingredients have been performed at high pH values, which are not representative to most Norwegian surface waters. Thus, the toxic effect of dithianon shown in these tests are likely to be lower than expected under typical conditions in Norway. On the assessment factors for concentration addition in fish: It is the opinion of the VKM panel that a reduction in assessment factor for one component in a mixture cannot be used for a formulation containing components for which a similar reduction has not been accepted. On effect studies of active substances and formulations on non-target arthropods: The VKM panel shares the view of KemI that the risk assessment should be based on all available information, including the studies presented for the active substances. On the endpoint in earthworm risk assessment: VKM supports the view of KemI that the observed effects of pyrimethanil on reproduction of earthworms should be considered in the risk assessment of Malakite.

scholarly journals DEVELOPMENT OF THE BLACK SEA HYDROBIONT RESOURCE STUDY METHOD AS A NEW ECONOMICALLY FEASIBLE DIRECTION OF PHARMACOLOGY AIMING TOWARD SAVE HUMAN HEALTH AND ECOLOGY

2021 ◽  
Vol 941 (1) ◽  
pp. 012023
Author(s):  
O P Chzhu ◽  
D E Araviashvili ◽  
A L Tumanova
Keyword(s):  
Black Sea ◽  
Extraction Method ◽  
Raw Materials ◽  
Aquatic Organisms ◽  
Biologically Active ◽  
The Black Sea ◽  
Phase Extraction ◽  
Biochemical Activity ◽  
Two Phase ◽  
Active Substances

Abstract The selection of the Black Sea aquatic area as a hydrobiont biologically active compound source allows resolving several environmental problems including development of an integrated hydrobiological resource management system for the Black Sea as a new sector of modern pharmacology. Aquatic organisms produce unique secondary metabolites. This paper presents the results of studies on the development of the biologically active substance extraction technology from non-commercial aquatic organisms as well as a preliminary assessment of the biochemical activity of the substrates obtained. Biologically active substances were extracted using the of two-phase extraction method in conjunction with ultrasound. For the substrates, the antioxidant activity was determined utilising the method that allow conducting screening of pharmaceutical raw materials and biologically active substances with high antioxidant activity. The protective activity evaluation was carried out during the study of the enzymatic alcoholic fermentation kinetics within a self-contained system. The evaluation of lymphocytes proliferative activities influenced by the obtained substrates was carried out using the cultivation method. The acquired data allows recommending the two-phase extraction method combined with ultrasonic voiceover as the effective one when processing analogical marine raw materials. The isolated substrates are characterised by a pronounced biochemical activity in relation to the living systems cells, which suggests a significant synergistic effect with derivatives of the microalgae Chlorella Vulgaris.

scholarly journals Towards an Understanding of the Mode of Action of Human Aromatase Activity for Azoles through Quantum Chemical Descriptors-Based Regression and Structure Activity Relationship Modeling Analysis

Molecules ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 739
Author(s):  
Chayawan Chayawan ◽  
Cosimo Toma ◽  
Emilio Benfenati ◽  
Ana Y. Caballero Alfonso
Keyword(s):  
Endocrine System ◽  
Spherical Shape ◽  
Aromatase Activity ◽  
Quantum Chemical Descriptors ◽  
Multilinear Regression ◽  
Chemical Safety ◽  
Antagonist Activity ◽  
Binding Behavior ◽  
Modeling Analysis ◽  
Human Aromatase

Aromatase is an enzyme member of the cytochrome P450 superfamily coded by the CYP19A1 gene. Its main action is the conversion of androgens into estrogens, transforming androstenedione into estrone and testosterone into estradiol. This enzyme is present in several tissues and it has a key role in the maintenance of the balance of androgens and estrogens, and therefore in the regulation of the endocrine system. With regard to chemical safety and human health, azoles, which are used as agrochemicals and pharmaceuticals, are potential endocrine disruptors due to their agonist or antagonist interactions with the human aromatase enzyme. This theoretical study investigated the active agonist and antagonist properties of “chemical classes of azoles” to determine the relationships of azole interaction with CYP19A1, using stereochemical and electronic properties of the molecules through classification and multilinear regression (MLR) modeling. The antagonist activities for the same substituent on diazoles and triazoles vary with its chemical composition and its position and both heterocyclic systems require aromatic substituents. The triazoles require the spherical shape and diazoles have to be in proper proportion of the branching index and the number of ring systems for the inhibition. Considering the electronic aspects, triazole antagonist activity depends on the electrophilicity index that originates from interelectronic exchange interaction (ωHF) and the LUMO energy ( E LUMO PM 7 ), and the diazole antagonist activity originates from the penultimate orbital ( E HOMONL PM 7 ) of diazoles. The regression models for agonist activity show that it is opposed by the static charges but favored by the delocalized charges on the diazoles and thiazoles. This study proposes that the electron penetration of azoles toward heme group decides the binding behavior and stereochemistry requirement for antagonist activity against CYP19A1 enzyme.

scholarly journals Epigenetic modifications associated with in utero exposure to endocrine disrupting chemicals BPA, DDT and Pb

2019 ◽  
Vol 34 (4) ◽  
pp. 309-325 ◽  
Author(s):  
Chinonye Doris Onuzulu ◽  
Oluwakemi Anuoluwapo Rotimi ◽  
Solomon Oladapo Rotimi
Keyword(s):  
Endocrine Disruptors ◽  
Endocrine Disrupting Chemicals ◽  
Endocrine System ◽  
Environmental Chemicals ◽  
Epigenetic Mechanisms ◽  
Epigenetic Alterations ◽  
Endocrine Disrupting ◽  
Non Coding Rnas ◽  
Hormone System ◽  
Developmental Windows

Abstract Endocrine disrupting chemicals (EDCs) are xenobiotics which adversely modify the hormone system. The endocrine system is most vulnerable to assaults by endocrine disruptors during the prenatal and early development window, and effects may persist into adulthood and across generations. The prenatal stage is a period of vulnerability to environmental chemicals because the epigenome is usually reprogrammed during this period. Bisphenol A (BPA), lead (Pb), and dichlorodiphenyltrichloroethane (DDT) were chosen for critical review because they have become serious public health concerns globally, especially in Africa where they are widely used without any regulation. In this review, we introduce EDCs and describe the various modes of action of EDCs and the importance of the prenatal and developmental windows to EDC exposure. We give a brief overview of epigenetics and describe the various epigenetic mechanisms: DNA methylation, histone modifications and non-coding RNAs, and how each of them affects gene expression. We then summarize findings from previous studies on the effects of prenatal exposure to the endocrine disruptors BPA, Pb and DDT on each of the previously described epigenetic mechanisms. We also discuss how the epigenetic alterations caused by these EDCs may be related to disease processes.

scholarly journals Assessment of current methods of laboratory diagnosis of bacterial vaginosis

2014 ◽  
Vol 63 (1) ◽  
pp. 26-32
Author(s):  
Kira Valentinovna Shalepo ◽  
Veronika Victorovna Nazarova ◽  
Yulia Nicolaevna Menukhova ◽  
Tatiana Andreevna Rumyantseva ◽  
Alexander Evgenievich Guschin ◽  
...  
Keyword(s):  
Polycystic Ovary ◽  
Free Testosterone ◽  
Antral Follicle ◽  
Laboratory Diagnosis ◽  
Reproductive Age ◽  
Blood Levels ◽  
Aromatase Activity ◽  
Women Of Reproductive Age ◽  
Ovary Syndrome ◽  
Antral Follicles

41 women with polycystic ovary syndrome (PCOS) and 15 healthy women of reproductive age were examined to evaluate ovarian aromatase activity. Aromatase activity was determined by the decrease of estradiol level after peroral intake of aromatase inhibitor letrosol. To examine aromatase activity of antral follicle (∆E2) was divided on the blood level of antimullerian hormone (AMH), which is corresponded to the number of antral follicles. Significant variations of aromatase activity of antral follicles in patients with PCOS were determined: in 34.1 % of women it was within physiological ranges, in 48.8 % of women it was decreased and in 17.1 % of women it was increased. Aromatase activity of antral follicles in patients with PCOS correlated with blood levels of estradiol (r = 0.67), estron (r = 0.27), free testosterone(r = 0.43), androstendion (r = 0.34) and body mass index (r = 0.30). Aromatase activity had reverse correlation with number of antral follicles. Athors suggest that the sensitivity of the ovaries to gonadotropinic stimulation is decreased in patients with PCOS and low aromatase activity.

scholarly journals Use of probiotics in aquaculture (a review)

2021 ◽  
pp. 59-81
Author(s):  
I. Zaloilo ◽  
◽  
O. Zaloilo ◽  
Yu. Rud ◽  
I. Hrytsyniak ◽  
...  
Keyword(s):  
Aquatic Organisms ◽  
Biologically Active ◽  
Antimicrobial Drugs ◽  
Scientific Publications ◽  
Basic Principles ◽  
Control And Prevention ◽  
Key Words Probiotics ◽  
Active Substances

Purpose. To analyze data of available specialized literature and summarize the information obtained on the use of probiotics in modern aquaculture. To review basic principles of classification of existing probiotics, methods of their introduction into the aquatic organisms and mechanisms of action of different probiotic groups. Findings. The analysis of scientific publications on the use of probiotics in aquaculture for efficient farming in order to reduce fish and shrimp mortality and, accordingly, increase the efficiency of farms has been provided. The literature data on the classification of probiotics depending on the composition and purpose are summarized. Modern and general ideas about the microbiota of aquaculture species are described. The actual ways of probiotic administration into the aquatic organisms are given. The main concepts of mechanisms and results of probiotics action on the host (suppression of pathogenic microflora, improving the quality of the aquatic environment, competition for localization and nutrients, providing the animal with immunostimulants, digestive enzymes and other biologically active substances). The prospects of using probiotics as an alternative to antimicrobial drugs and chemical remedies in aquaculture are shown. Practical value. The review may be useful for scientists investigating alternative treatments of aquaculture objects and the interaction of aquatic organisms with probiotics. Key words: probiotics, aquaculture, control and prevention of fish diseases, aquatic organisms, alternatives to antibiotics.

scholarly journals Elucidating the Links Between Endocrine Disruptors and Neurodevelopment

Endocrinology ◽  
2015 ◽  
Vol 156 (6) ◽  
pp. 1941-1951 ◽  
Author(s):  
Thaddeus T. Schug ◽  
Ashley M. Blawas ◽  
Kimberly Gray ◽  
Jerrold J. Heindel ◽  
Cindy P. Lawler
Keyword(s):  
Endocrine Disrupting Chemicals ◽  
Endocrine System ◽  
The United States ◽  
Autism Spectrum ◽  
Learning Disorders ◽  
Environmental Chemicals ◽  
Neurodevelopmental Outcomes ◽  
Nutritional Factors ◽  
Hyperactivity Disorder ◽  
Endocrine Disrupting

Abstract Recent data indicate that approximately 12% of children in the United States are affected by neurodevelopmental disorders, including attention deficit hyperactivity disorder, learning disorders, intellectual disabilities, and autism spectrum disorders. Accumulating evidence indicates a multifactorial etiology for these disorders, with social, physical, genetic susceptibility, nutritional factors, and chemical toxicants acting together to influence risk. Exposure to endocrine-disrupting chemicals during the early stages of life can disrupt normal patterns of development and thus alter brain function and disease susceptibility later in life. This article highlights research efforts and pinpoints approaches that could shed light on the possible associations between environmental chemicals that act on the endocrine system and compromised neurodevelopmental outcomes.

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