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1.
Environ Toxicol ; 39(6): 3523-3536, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38465474

RESUMO

A previous study using miRNA sequencing revealed that exposure to a mixture of phthalates during pregnancy and lactation dysregulated rno-miR-184 and rno-miR-141-3p in the ventral prostate (VP) of offspring. Here, rno-miR-184 and rno-miR-141-3 expressions were obtained by RT-qPCR in the VP of F1 males as well as in F2 offspring, aiming to establish a relationship with possible oncogenic targets through in silico analyses with multigenerational approach. Additionally, some targets were measured by western blots to highlight a possible relationship between the deregulated miRNAs and some of their targets. VP samples from rats exposed to a mixture of phthalates maternally during pregnancy and lactation (GD10 to PND21-F1) and VP from offspring (F2) were examined. The phthalate mixture at both concentrations (20 µg and 200 mg/kg/day) increased the expression of both miRNAs in the F1 (PND22 and 120) and F2 (descendants of F1-treated males) prostate. Target prediction analysis revealed that both microRNAs are responsible for modulating the expression and synthesis of 40 common targets. A phthalate target association analysis and the HPA database showed an interesting relationship among these possible miRNAs modulated targets with prostate adenocarcinoma and other oncogenic processes. Western blots showed alteration in P63, P53, WNT5, and STAT3 expression, which are targeted by the miRNAs, in the VP of F1/F2 males. The data draw attention to the epigenetic modulation in the prostate of descendants exposed to phthalates and adds to one of the few currently found in the literature to point to microRNAs signature as biomarkers of exposure to plasticizers.


Assuntos
MicroRNAs , Ácidos Ftálicos , Efeitos Tardios da Exposição Pré-Natal , Neoplasias da Próstata , MicroRNAs/genética , MicroRNAs/metabolismo , Masculino , Animais , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Feminino , Ácidos Ftálicos/toxicidade , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/genética , Exposição Materna/efeitos adversos , Próstata/efeitos dos fármacos , Próstata/patologia , Ratos Wistar , Ratos , Simulação por Computador
2.
Int J Gynaecol Obstet ; 164(1): 40-46, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37318113

RESUMO

The relationship between events occurring during intrauterine development and later-life predisposition to long-term disease, has been described. The fetus responds to excess intrauterine exposure to high levels of corticosteroids, modifying their physiological development and stopping their growth. Fetal exposure to elevated levels of either endogenous (alterations in fetal hypothalamic-pituitary-adrenal axis) or synthetic corticosteroids, is one model of early-life adversity; to developing adult disease. At the molecular level, there are transcriptional changes in metabolic and growth pathways. Epigenetic mechanisms participate in transgenerational inheritance, not genomic. Exposures that change 11ß-hydroxysteroid dehydrogenase type 2 enzyme methylation status in the placenta can result in transcriptional repression of the gene, causing the fetus to be exposed to higher levels of cortisol. More precise diagnosis and management of antenatal corticosteroids for preterm birth, would potentially decrease the risk of long-term adverse outcomes. More studies are needed to understand the potential roles of factors to alter fetal corticosteroid exposure. Long-term infant follow-up is required to determine whether methylation changes in placenta may represent useful biomarkers of later disease risk. This review, summarize recent advances in the programming of fetal effects of corticosteroid exposure, the role of corticosteroids in epigenetic gene regulation of placental 11ß-hydroxysteroid dehydrogenase type 2 enzyme expression and transgenerational effects.


Assuntos
Placenta , Nascimento Prematuro , Adulto , Gravidez , Feminino , Recém-Nascido , Humanos , Placenta/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/genética , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/farmacologia , Sistema Hipotálamo-Hipofisário/fisiologia , Sistema Hipófise-Suprarrenal/fisiologia , Nascimento Prematuro/induzido quimicamente , Feto , Glucocorticoides/efeitos adversos , Epigênese Genética , Desenvolvimento Fetal/fisiologia
3.
Insects ; 11(9)2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32824905

RESUMO

Plants are challenged by biotic and abiotic stress factors and the incidence of one can increase or decrease resistance to another. These relations can also occur transgenerationally. For instance, progeny plants whose mothers experienced herbivory can be more resistant to herbivores. Certain fungal endophytes that are vertically transmitted endow plants with alkaloids and resistance to herbivores. However, endophyte-symbiotic plants exposed to the oxidative agent ozone became susceptible to aphids. Here, we explored whether this effect persists transgenerationally. We exposed Lolium multiflorum plants with and without fungal endophyte Epichloë occultans to ozone (120 or 0 ppb), and then, challenged the progeny with aphids (Rhopalosiphum padi). The endophyte was the main factor determining the resistance to aphids, but its importance diminished in plants with ozone history. This negative ozone effect on the endophyte-mediated resistance was apparent on aphid individual weights. Phenolic compounds in seeds were increased by the symbiosis and diminished by the ozone. The endophyte effect on phenolics vanished in progeny plants while the negative ozone effect persisted. Independently of ozone, the symbiosis increased the plant biomass (≈24%). Although ozone can diminish the importance of endophyte symbiosis for plant resistance to herbivores, it would be compensated by host growth stimulation.

4.
J Exp Biol ; 223(Pt 17)2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32680897

RESUMO

The perception, processing and response to environmental challenges involves the activation of the immuno-neuroendocrine (INE) interplay. Concerted environmental challenges might induce trade-off when resource allocation to one trait occurs at the expense of another, also producing potential transgenerational effects in the offspring. We evaluated whether concerted challenges, in the form of an immune inoculum against inactivated Salmonella enteritidis (immune challenge, ICH) and a chronic heat stress (CHS) exposure on adult Japanese quail, modulate the INE responses of the parental generation and their offspring. Adults were inoculated and later exposed to a CHS along nine consecutive days. For the last 5 days of the CHS, eggs were collected for incubation. Chicks were identified according to their parental treatments and remained undisturbed. Induced inflammatory response, heterophil/lymphocyte (H/L) ratio and specific humoral response against sheep red blood cells (SRBC) were evaluated in both generations. Regardless of the ICH, stressed adults showed a reduced inflammatory response and an elevated H/L ratio compared with controls. In offspring, the inflammatory response was elevated and the specific SRBC antibody titres were diminished in those chicks prenatally exposed to CHS, regardless of the ICH. No differences were found in the H/L ratio of the offspring. Together, our results suggest that CHS exposure influences the INE interplay of adult quail, establishing trade-offs within their immune system. Moreover, CHS not only affected parental INE responses but also modulated their offspring INE responses, probably affecting their potential to respond to future challenges. The adaptability of the developmental programming of offspring would depend on the environment encountered.


Assuntos
Formação de Anticorpos , Coturnix , Animais , Ovos , Resposta ao Choque Térmico , Linfócitos , Ovinos
5.
Ann Bot ; 125(6): 981-991, 2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32010946

RESUMO

BACKGROUND AND AIMS: The processes that maintain variation in the prevalence of symbioses within host populations are not well understood. While the fitness benefits of symbiosis have clearly been shown to drive changes in symbiont prevalence, the rate of transmission has been less well studied. Many grasses host symbiotic fungi (Epichloë spp.), which can be transmitted vertically to seeds or horizontally via spores. These symbionts may protect plants against herbivores by producing alkaloids or by increasing tolerance to damage. Therefore, herbivory may be a key ecological factor that alters symbiont prevalence within host populations by affecting either symbiont benefits to host fitness or the symbiont transmission rate. Here, we addressed the following questions: Does symbiont presence modulate plant tolerance to herbivory? Does folivory increase symbiont vertical transmission to seeds or hyphal density in seedlings? Do plants with symbiont horizontal transmission have lower rates of vertical transmission than plants lacking horizontal transmission? METHODS: We studied the grass Poa autumnalis and its symbiotic fungi in the genus Epichloë. We measured plant fitness (survival, growth, reproduction) and symbiont transmission to seeds following simulated folivory in a 3-year common garden experiment and surveyed natural populations that varied in mode of symbiont transmission. KEY RESULTS: Poa autumnalis hosted two Epichloë taxa, an undescribed vertically transmitted Epichloë sp. PauTG-1 and E. typhina subsp. poae with both vertical and horizontal transmission. Simulated folivory reduced plant survival, but endophyte presence increased tolerance to damage and boosted fitness. Folivory increased vertical transmission and hyphal density within seedlings, suggesting induced protection for progeny of damaged plants. Across natural populations, the prevalence of vertical transmission did not correlate with symbiont prevalence or differ with mode of transmission. CONCLUSIONS: Herbivory not only mediated the reproductive fitness benefits of symbiosis, but also promoted symbiosis prevalence by increasing vertical transmission of the fungus to the next generation. Our results reveal a new mechanism by which herbivores could influence the prevalence of microbial symbionts in host populations.


Assuntos
Epichloe , Poa , Endófitos , Herbivoria , Poaceae , Simbiose
6.
Nutr Neurosci ; 23(6): 411-421, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30126346

RESUMO

Introduction: Obesity promotes hypothalamic inflammation and local morphological changes in astrocytes, including the increased expression of the astrocytic biomarker glial fibrillary acidic protein (GFAP), which is seen as a sign of neuroinflammation.Objective: This study aimed to observe the astrocytic expression of GFAP in different brain areas from female rats that received a hypercaloric (HD) or a normocaloric (ND) diet during puberty (F0 generation) as well as in their male pups (F1 generation).Methods: Female rats received highly palatable HD (Ensure®) or ND from postnatal day (PND) 23-65. On PND90-95, some were euthanized for the immunohistochemical study and some were mated to obtain the F1 generation. Male pups were immunochallenged on PND50 with lipopolysaccharide (LPS, 100 µg/kg) or 0.9% saline solution (1 mL/kg) intraperitoneal injection. Body weight (BW) and retroperitoneal fat weight (RFW) were recorded on PND95 for F0 generation and on PND50 for F1 generation. GFAP expression for both generations was assessed by morphometry in the parietal/frontal cortex, corpus callosum, nucleus accumbens, arcuate/periventricular nuclei of hypothalamus, pons, molecular/granular layers of cerebellum.Results: Female rats fed with HD presented a significant increase in the GFAP expression in all evaluated areas as well as in the RFW. Male rats born from mothers that received HD showed decreased GFAP expression, BW and RFW when treated with LPS in relation to those from mothers fed with ND.Discussion: HD induced astrogliosis in several brain areas in females from F0 generation and an adaptive phenotypic change of decreased GFAP expression in males from F1 generation after LPS challenge.


Assuntos
Astrócitos/metabolismo , Encéfalo/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Obesidade/metabolismo , Animais , Encefalite/metabolismo , Ingestão de Energia , Feminino , Gliose/metabolismo , Lipopolissacarídeos , Masculino , Ratos Wistar
7.
Prog Brain Res ; 245: 247-261, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30961869

RESUMO

An increasing interest has been developed in the past 15 years in the relationship between trace elements and cell functioning. In the present work the possibility of transgenerational effects of Te was investigated in rats. F1 generation exposed to K2TeO3 (1.55nM) from day 1 of pregnancy until litters were 30 day old, these animals with no other treatment than tap water and food were let to reach 60-70 day old. At this age, female rats were mated with normal untreated male rats. The F2 generation also without any Te treatment was allowed to grow until 30 days of age. At this age, behavioral tests measuring exploration induced by novelty, lateralized exploration, social interaction and survival behavior were applied. Results showed that head-dipping, rearing, lateralized exploration, social interaction, and survival behaviors, affected by Te treatment in F1 generation, also were modified in the same manner in F2 generation. These data show that Te effects on coping behavior in rats are preserved epigenetically in the next generation.


Assuntos
Adaptação Psicológica , Comportamento Animal , Epigênese Genética , Efeitos Tardios da Exposição Pré-Natal , Telúrio/farmacologia , Oligoelementos/farmacologia , Animais , Feminino , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley , Telúrio/administração & dosagem , Oligoelementos/administração & dosagem
8.
Chemosphere ; 219: 678-683, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30557724

RESUMO

Chlorantraniliprole (CAP) is a reduced risk insecticide, which used as seed treatment in many crops. However, CAP residues can contaminate pollen and nectar, becoming a potential risk to beneficial arthropods. The aims of this study were to (1) determine the non-target effects of CAP seed treatment of cotton on Harmonia axyridis (Coleoptera: Coccinellidae) over two generations, and (2) assess the ability of the lady beetles to avoid plants grown from treated seeds. The exposure of H. axyridis larvae and adults to cotton seedlings grown from CAP treated seeds did not have a significantly affect on any life history parameters of the lady beetles directly exposed (F0). However, CAP caused significant transgenerational effects in the both larval and adult stages of H. axyridis. The CAP treatment of larvae exposure reduced the larval and pupal developmental time and the male body weight of F1 generation as well as the survival of the lady beetles over the developmental stages. In the adult bioassay, CAP seed treatment reduced both pupal developmental time and egg viability of F1 generation and decreased the survival of H. axyridis over the F1 generation developmental. In olfactometer test, only the H. axyridis larvae were able to avoid cotton seedlings grown from CAP treated seeds. The results of this study confirm the hypothesis that systemic insecticides, when applied to seed treatments, can cause negative effects on non-target organisms. In addition, the study emphasizes the importance of long-term assessments of the pesticides side-effects on beneficial arthropods.


Assuntos
Besouros/efeitos dos fármacos , Estágios do Ciclo de Vida/efeitos dos fármacos , Sementes/química , ortoaminobenzoatos/farmacologia , Animais , Efeito de Coortes , Comportamento Alimentar/efeitos dos fármacos , Inseticidas/farmacologia , Masculino
9.
Environ Sci Pollut Res Int ; 24(21): 17534-17546, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28597380

RESUMO

Chapalichthys pardalis is a viviparous fish, microendemic to the Tocumbo Region in the state of Michoacán, Mexico. Despite the peculiar type of reproduction of goodeid fish and their mother-embryo interaction, the effects on embryos induced by maternal exposure to aquatic xenobiotics are still unknown. The objective of the present work was to determine the maternal-embryonic metabolic and antioxidant response of C. pardalis exposed to 3,4-dichloroaniline (3,4-DCA), a compound considered highly noxious to the environment because of its high toxicity and persistence, which has been used as reference toxicant in toxicological bioassays. We determined the median lethal concentration (LC50, 96 h) and then exposed pregnant females to 3.3, 2.5, and 0.5 mg L-1 of 3,4-DCA (equivalent to LC1, LC0.01, and LC50/10, respectively) during 21 days. We assessed the activity of antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), macromolecules content (proteins, lipids, carbohydrates), glucose, and lactate concentration, as well as the oxidative damage, by measuring thiobarbituric acid reactive substances, and protein oxidation. To interpret results, we used the integrated biomarker response (IBRv2). The average LC50 was of 5.18 mg L-1 (4.8-5.5 mg L-1; p = 0.05). All females exposed to concentrations of 3.3 and 2.5 mg L-1 lost 100% of the embryos during the bioassay, whereas those exposed to 0.5 mg L-1 showed alterations in the antioxidant activity and oxidative damage, being the embryos and the maternal liver the most affected, with IBRv2 values of 10.09 and 9.21, respectively. Damage to macromolecules was greater in embryos and the maternal liver, with IBRv2 of 16.14 and 8.40, respectively. We conclude that exposure to xenobiotics, like 3,4-DCA, in species with a marked maternal-embryonic interaction represents a potential risk for the development and survival of the descendants, thereby, potentially affecting the future of the population.


Assuntos
Compostos de Anilina/uso terapêutico , Antioxidantes , Peixes/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Catalase , Feminino , México , Estresse Oxidativo , Gravidez , Prenhez , Superóxido Dismutase
10.
Neotrop Entomol ; 45(2): 192-200, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26842914

RESUMO

The aim of this study was to compare the side-effects of glyphosate to the parasitoid Telenomus remus Nixon (Hymenoptera: Platygastridae) when parasitoids were exposed to this chemical at the pupal (inside host eggs) and adult stages. Bioassays were conducted under laboratory conditions according to the International Organization for Biological Control (IOBC) standard methods for testing side-effects of pesticides to egg parasitoids. Different glyphosate-based pesticides (Roundup Original®, Roundup Ready®, Roundup Transorb®, Roundup WG®, and Zapp Qi®) were tested at the same acid equivalent concentration. Treatments were classified following the IOBC toxicity categories as (1) harmless, (2) slightly harmful, (3) moderately harmful, and (4) harmful. When tested against T. remus adults, Roundup Original®, Roundup Ready®, Roundup Transorb®, and Roundup WG® reduced parasitism 2 days after parasitoid emergence, being classified as slightly harmful. Differently, when tested against T. remus pupae, all tested glyphosate-based products did not differ in their lethal effect and therefore did not reduce T. remus adult emergence or parasitism capacity, being classified as harmless. However, differences on sublethal toxicity were found. Parasitism of individuals emerging from parasitized eggs sprayed at the pupal stage of T. remus with Zapp Qi® was lower compared to control, but parasitism was still higher than 66%, and therefore, Zapp Qi® was still classified as harmless. In conclusion, all tested glyphosate-based products can be used in agriculture without negative impact to T. remus as none was classified as harmful or moderately harmful to this parasitoid when exposure occurred at the pupal or adult stages.


Assuntos
Glicina/análogos & derivados , Herbicidas/toxicidade , Himenópteros/efeitos dos fármacos , Agricultura , Animais , Glicina/toxicidade , Pupa , Glifosato
11.
Ecotoxicology ; 24(9): 1869-79, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26250937

RESUMO

The combination of chemical and biological controls is a historic goal of integrated pest management, but has rarely been achieved due to lethal and sublethal impact of insecticides on natural enemies altering their performance. In this context, the susceptibility of the yellow sugarcane borer, Diatraea flavipennella (Lepidoptera: Crambidae), to the insect growth regulator lufenuron and the consequent effects upon its endoparasitoid Cotesia flavipes (Hymenoptera: Braconidae) encountering exposed but surviving larvae were studied. Neonate and 10-day-old larvae were subjected to one of seven concentrations of lufenuron (1.56, 3.12, 6.25, 12.5, 25.0, 50.0 and 100 mg a.i./L). Further, effects of lufenuron to the host larvae and to the parasitoid were assessed using low lethal LC20 and LC50. Lufenuron at concentrations up to 12.5 mg a.i./L allowed partial survival of borer larvae; and concentrations over 12.5 mg a.i./L caused 100 % larval mortality before pupation in both ages. Neonate larvae exhibited lower pupal weights only at concentrations 12.5 mg a.i./L; while 10-day-old larvae treated with the LC50 exhibited delayed development. Egg viability was reduced for adult borers from surviving larvae of both ages treated with low lethal concentrations. The parasitoid C. flavipes successfully parasitized surviving low lethal treated larvae. Among the studied life history characteristics of C. flavipes, only a delayed development was observed. The results showed that lufenuron can be effective against D. flavipennella at concentrations over 25 mg a.i./L, and that surviving larvae can be successfully parasitized by C. flavipes. The insecticide lufenuron and the parasitoid C. flavipes seem to be compatible for sugarcane borer control.


Assuntos
Benzamidas/farmacologia , Inseticidas/farmacologia , Hormônios Juvenis/farmacologia , Mariposas/efeitos dos fármacos , Vespas/efeitos dos fármacos , Animais , Benzamidas/toxicidade , Relação Dose-Resposta a Droga , Interações Hospedeiro-Parasita/efeitos dos fármacos , Controle de Insetos , Inseticidas/toxicidade , Hormônios Juvenis/toxicidade , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/parasitologia , Larva/fisiologia , Mariposas/crescimento & desenvolvimento , Mariposas/parasitologia , Controle Biológico de Vetores , Vespas/crescimento & desenvolvimento , Vespas/fisiologia
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