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1.
Conserv Biol ; : e14249, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38488313

RESUMEN

Conservationists increasingly position conservation that is mutually beneficial to people and biodiversity on the promise of empowerment of people through participatory discourse, metrics, processes, and outcomes. Empowerment represents multidimensional concepts and theories that permeate the interlinking levels of power, from the psychological to the political, and social scales in which conservation operates. The multifaceted nature of empowerment makes it challenging to understand, pursue, and evaluate as a central philosophical commitment and goal-oriented practice in conservation. Moreover, definitional and methodological uncertainty may disempower interested and affected groups because they can foster conceptual assumptions that reinforce institutionalized barriers to systemic changes. Despite these complexities, there are no targeted reviews of empowerment in conservation. We conducted a scoping review of the conservation literature to synthesize the meanings and uses of empowerment in the field. We reviewed 121 of the most cited conservation articles that invoked or assessed empowerment from 1992 to 2017 to document geographic, conceptual, and methodological trends in the scales and theories of empowerment deployed by conservationists. Research claiming or assessing empowerment through conservation often focused on communities in the Global South. Most studies relied on qualitative and mixed methods (78%) collected largely from male or non-Indigenous participants. Few studies (30%) defined the 20 types of empowerment they referenced. Fewer studies (3%) applied empowerment theories in their work. Our findings show that empowerment discourse of local and Indigenous communities permeates the discourse of people-centered conservation. Yet, overreliance on empowerment's rhetorical promise and minimal engagement with theory (e.g., postcolonial theory) risks disempowering people by obscuring empowerment's foundational value to conservation and communities and oversimplifying the complex realities of people-centered conservation. Lasting change could come from more meaningful engagement with empowerment, including coproducing definitions and measures with and for disempowered social groups to tackle widespread power disparities in conservation today.


El alcance del empoderamiento para la conservación y las comunidades Resumen Con frecuencia los conservacionistas posicionan a la conservación como benéfica para las personas y la biodiversidad mediante discursos, medidas, procesos y resultados participativos que prometen el empoderamiento de la gente. El empoderamiento representa conceptos y teorías multidimensionales que permean los niveles interconectados de poder, desde el psicológico al político, y las escalas sociales en las que opera la conservación. La naturaleza multifacética del empoderamiento complica que se entienda, se dé seguimiento y se evalúe como un compromiso filosófico central y una práctica orientada hacia las metas dentro de la conservación. Además, la incertidumbre metodológica y de definición pueden restar autoridad a los grupos interesados o afectados pues pueden promover suposiciones conceptuales que refuerzan las barreras institucionales de los cambios sistémicos. A pesar de estas complejidades, no existen revisiones focalizadas del empoderamiento en la conservación. Realizamos una revisión de alcance de la literatura de conservación para sintetizar los significados y usos de la palabra empoderamiento en este campo. Revisamos 121 de los artículos sobre conservación más citados que invocaron o evaluaron el empoderamiento entre 1992 y 2017 para documentar las tendencias geográficas, conceptuales y metodológicas en las escalas y teorías del empoderamiento usadas por los conservacionistas. La mayoría de los artículos que afirmaban o evaluaban el empoderamiento por medio de la conservación se enfocaron en comunidades del Sur Global. La mayoría de los estudios dependieron de métodos cualitativos y mixtos (78%) tomados principalmente de participantes masculinos o no indígenas. Pocos estudios (30%) definieron los 20 tipos de empoderamiento que referenciaron. Todavía menos estudios (3%) aplicaron las teorías de empoderamiento a su trabajo. Nuestros descubrimientos muestran que el discurso de empoderamiento de las comunidades locales e indígenas permea el discurso de la conservación centrada en la gente. Sin embargo, depender en exceso de la promesa retórica del empoderamiento e involucrarse en lo mínimo con la teoría (p. ej.: teoría postcolonial) arriesga que la gente se pierda autoridad al oscurecer el valor fundamental que tiene el empoderamiento para la conservación y las comunidades y simplificar sobremanera las realidades complejas de la conservación centrada en las personas. El cambio duradero podría venir de involucrarse de forma más significativa con el empoderamiento, lo que incluye la coproducción de definiciones y medidas con y para los grupos sociales no empoderados para resolver la disparidad de poder que existe hoy en día en la conservación.

2.
Environ Res ; 250: 118492, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38373550

RESUMEN

Dioxin-like pollutants (DLPs), such as polychlorinated biphenyl 126 (PCB 126), are synthetic chemicals classified as persistent organic pollutants. They accumulate in adipose tissue and have been linked to cardiometabolic disorders, including fatty liver disease. The toxicity of these compounds is associated with activation of the aryl hydrocarbon receptor (Ahr), leading to the induction of phase I metabolizing enzyme cytochrome P4501a1 (Cyp1a1) and the subsequent production of reactive oxygen species (ROS). Recent research has shown that DLPs can also induce the xenobiotic detoxification enzyme flavin-containing monooxygenase 3 (FMO3), which plays a role in metabolic homeostasis. We hypothesized whether genetic deletion of Fmo3 could protect mice, particularly in the liver, where Fmo3 is most inducible, against PCB 126 toxicity. To test this hypothesis, male C57BL/6 wild-type (WT) mice and Fmo3 knockout (Fmo3 KO) mice were exposed to PCB 126 or vehicle (safflower oil) during a 12-week study, at weeks 2 and 4. Various analyses were performed, including hepatic histology, RNA-sequencing, and quantitation of PCB 126 and F2-isoprostane concentrations. The results showed that PCB 126 exposure caused macro and microvesicular fat deposition in WT mice, but this macrovesicular fatty change was absent in Fmo3 KO mice. Moreover, at the pathway level, the hepatic oxidative stress response was significantly different between the two genotypes, with the induction of specific genes observed only in WT mice. Notably, the most abundant F2-isoprostane, 8-iso-15-keto PGE2, increased in WT mice in response to PCB 126 exposure. The study's findings also demonstrated that hepatic tissue concentrations of PCB 126 were higher in WT mice compared to Fmo3 KO mice. In summary, the absence of FMO3 in mice led to a distinctive response to dioxin-like pollutant exposure in the liver, likely due to alterations in lipid metabolism and storage, underscoring the complex interplay of genetic factors in the response to environmental toxins.


Asunto(s)
Ratones Endogámicos C57BL , Ratones Noqueados , Estrés Oxidativo , Oxigenasas , Bifenilos Policlorados , Animales , Oxigenasas/genética , Oxigenasas/metabolismo , Bifenilos Policlorados/toxicidad , Estrés Oxidativo/efectos de los fármacos , Ratones , Masculino , Hígado/efectos de los fármacos , Hígado/metabolismo , Contaminantes Ambientales/toxicidad
3.
BMC Psychiatry ; 23(1): 766, 2023 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-37853373

RESUMEN

BACKGROUND: Cardiovascular disease disproportionately affects African Americans. Psychosocial factors, including the experience of and emotional reactivity to racism and interpersonal stressors, contribute to the etiology and progression of cardiovascular disease through effects on health behaviors, stress-responsive neuroendocrine axes, and immune processes. The full pathway and complexities of these associations remain underexamined in African Americans. The Heart of Detroit Study aims to identify and model the biopsychosocial pathways that influence cardiovascular disease risk in a sample of urban middle-aged and older African American adults. METHODS: The proposed sample will be composed of 500 African American adults between the ages of 55 and 75 from the Detroit urban area. This longitudinal study will consist of two waves of data collection, two years apart. Biomarkers of stress, inflammation, and cardiovascular surrogate endpoints (i.e., heart rate variability and blood pressure) will be collected at each wave. Ecological momentary assessments will characterize momentary and daily experiences of stress, affect, and health behaviors during the first wave. A proposed subsample of 60 individuals will also complete an in-depth qualitative interview to contextualize quantitative results. The central hypothesis of this project is that interpersonal stressors predict poor cardiovascular outcomes, cumulative physiological stress, poor sleep, and inflammation by altering daily affect, daily health behaviors, and daily physiological stress. DISCUSSION: This study will provide insight into the biopsychosocial pathways through which experiences of stress and discrimination increase cardiovascular disease risk over micro and macro time scales among urban African American adults. Its discoveries will guide the design of future contextualized, time-sensitive, and culturally tailored behavioral interventions to reduce racial disparities in cardiovascular disease risk.


Asunto(s)
Negro o Afroamericano , Enfermedades Cardiovasculares , Factores de Riesgo de Enfermedad Cardiaca , Racismo , Determinantes Sociales de la Salud , Anciano , Humanos , Persona de Mediana Edad , Negro o Afroamericano/psicología , Negro o Afroamericano/estadística & datos numéricos , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etnología , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/psicología , Inflamación , Estudios Longitudinales , Grupos Raciales , Racismo/etnología , Racismo/psicología , Estrés Psicológico/epidemiología , Estrés Psicológico/etnología , Estrés Psicológico/etiología , Estrés Psicológico/psicología , Michigan/epidemiología , Actividades Humanas/psicología , Actividades Humanas/estadística & datos numéricos , Población Urbana , Determinantes Sociales de la Salud/etnología , Determinantes Sociales de la Salud/estadística & datos numéricos , Biomarcadores/análisis
4.
Toxicol Appl Pharmacol ; 456: 116284, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36270329

RESUMEN

Genetic and environmental factors impact on the interindividual variability of susceptibility to communicable and non-communicable diseases. A class of ubiquitous chemicals, Per- and polyfluoroalkyl substances (PFAS) have been linked in epidemiological studies to immunosuppression and increased susceptibility to viral infections, but possible mechanisms are not well elucidated. To begin to gain insight into the role of PFAS in susceptibility to one such viral infection, Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), male and female C57BL/6 J mice were exposed to control water or a mixture of 5 PFAS (PFOS, PFOA, PFNA, PFHxS, Genx) for 12 weeks and lungs were isolated for examination of expression of SARS-CoV-2-related receptors Angiotensin-Converting Enzyme 2 (ACE2) and others. Secondary analyses included circulating hormones and cytokines which have been shown to directly or indirectly impact on ACE2 expression and severity of viral infections. Changes in mRNA and protein expression were analyzed by RT-qPCR and western blotting and circulating hormones and cytokines were determined by ELISA and MESO QuickPlex. The PFAS mixture decreased Ace2 mRNA 2.5-fold in male mice (p < 0.0001), with no significant change observed in females. In addition, TMPRSS2, ANPEP, ENPEP and DPP4 (other genes implicated in COVID-19 infection) were modulated due to PFAS. Plasma testosterone, but not estrogen were strikingly decreased due to PFAS which corresponded to PFAS-mediated repression of 4 representative pulmonary AR target genes; hemoglobin, beta adult major chain (Hbb-b1), Ferrochelatase (Fech), Collagen Type XIV Alpha 1 Chain (Col14a1), 5'-Aminolevulinate Synthase 2 (Alas2). Finally, PFAS modulated circulating pro and anti-inflammatory mediators including IFN-γ (downregulated 3.0-fold in females; p = 0.0301, 2.1-fold in males; p = 0.0418) and IL-6 (upregulated 5.6-fold in males; p = 0.030, no change in females). In conclusion, our data indicate long term exposure to a PFAS mixture impacts mechanisms related to expression of ACE2 in the lung. This work provides a mechanistic rationale for important future studies of PFAS exposure and subsequent viral infection.


Asunto(s)
COVID-19 , Fluorocarburos , Masculino , Femenino , Ratones , Animales , Enzima Convertidora de Angiotensina 2 , SARS-CoV-2 , Fluorocarburos/toxicidad , Citocinas , Ratones Endogámicos C57BL , Pulmón , Hormonas , ARN Mensajero
5.
J Lipid Res ; 61(1): 45-53, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31604806

RESUMEN

Elevated circulating levels of ceramides (Cers) are associated with increased risk of cardiometabolic diseases, and Cers may play a causative role in metabolic dysfunction that precedes cardiac events, such as mortality as a result of coronary artery disease. Although the mechanisms involved are likely complex, these associations suggest that lowering circulating Cer levels could be protective against cardiovascular diseases. Conversely, dietary fibers, such as inulin, have been reported to promote cardiovascular and metabolic health. However, the mechanisms involved in these protective processes also are not well understood. We studied the effects of inulin on lipid metabolism with a model of atherosclerosis in LDL receptor-deficient mice using lipidomics and transcriptomics. Plasma and tissues were collected at 10 days and/or 12 weeks after feeding mice an atherogenic diet supplemented with inulin or cellulose (control). Compared with controls, inulin-fed mice displayed a decreased C16:0/C24:0 plasma Cer ratio and lower levels of circulating Cers associated with VLDL and LDL. Liver transcriptomic analysis revealed that Smpd3, a gene that encodes neutral SMase (NSMase), was downregulated by 2-fold in inulin-fed mice. Hepatic NSMase activity was 3-fold lower in inulin-fed mice than in controls. Furthermore, liver redox status and compositions of phosphatidylserine and FFA species, the major factors that determine NSMase activity, were also modified by inulin. Taken together, these results showed that, in mice, inulin can decrease plasma Cer levels through reductions in NSMase expression and activity, suggesting a mechanism by which fiber could reduce cardiometabolic disease risk.


Asunto(s)
Ceramidas/antagonistas & inhibidores , Inulina/farmacología , Esfingomielina Fosfodiesterasa/antagonistas & inhibidores , Animales , Ceramidas/sangre , Biología Computacional , Suplementos Dietéticos , Regulación hacia Abajo/efectos de los fármacos , Inulina/administración & dosificación , Lipidómica , Masculino , Ratones , Ratones Noqueados , Receptores de LDL/deficiencia , Receptores de LDL/metabolismo , Esfingomielina Fosfodiesterasa/genética , Esfingomielina Fosfodiesterasa/metabolismo
6.
Conserv Biol ; 34(2): 338-353, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31334895

RESUMEN

Hunting presents a paradox for biodiversity conservation. It is both a problem and a solution to species declines and poverty. Yet, conservation scientists hold different assumptions about the significance and sustainability of hunting based on the cultures and identities of hunters. In Latin America, conservationists largely sort hunters as either indigenous or campesino. Indigenous hunters are often characterized as culturally driven stewards of wildlife sustainability. Campesino hunters, by contrast, are described as peasants-cultureless, uneducated, and uncaring toward wildlife sustainability. Although such ethnically fueled hunting discourse promotes hunting research, campesino hunters remain underrepresented in most comparative hunting reviews. Moreover, there are no targeted syntheses on the current state of knowledge about campesino hunting, nothing to guide conservation research and practice with and for the largest group of hunters in Latin America. We reviewed 334 articles published from 1937 to 2018 in English (55%) and Spanish (45%)-mostly published in 145 peer-reviewed journals-on the meanings, motivations, and sustainability of campesino hunting in Latin America. Although studies spanned 17 countries, 7 ecosystems, and >75 indigenous and nonindigenous demographics in 30 research contexts, they predominantly focused on nonindigenous campesinos for species-specific conservation and protected area management in tropical broadleaf forests of Mexico, Peru, and Colombia. Authors used 12 methods to collect campesino hunting data, primarily interviews, surveys, and questionnaires, and drew from 10 local and traditional knowledge themes about wildlife trends and uses. Eighteen drivers, 14 constraints, and 10 conflicts-mainly subsistence, income, ethics, regulations, and crop or livestock protection-shaped whether campesino hunters pursued 799 species, 70% of which were least concern species. Yet, only 25 studies (8%) empirically assessed sustainability. Our results show the need for increased interdisciplinary and geographic engagement with campesino hunting across Latin America.


Cacería Campesina y Conservación en América Latina Resumen La cacería representa una paradoja para la conservación de la biodiversidad ya que es tanto un problema como una solución para la declinación de especies y la pobreza. Aun así, los científicos de la conservación mantienen suposiciones diferentes sobre la relevancia y la sustentabilidad de la cacería basada en la cultura e identidad de los cazadores. En América Latina, los conservacionistas generalmente clasifican a los cazadores como indígenas o campesinos. Los cazadores indígenas casi siempre están caracterizados como administradores de la sustentabilidad de fauna influenciados culturalmente. Como contraste, los cazadores campesinos están descritos como personas rurales - sin cultura ni educación y sin preocupación por la sustentabilidad de la fauna. Aunque tal discurso de cacería avivado étnicamente promueve la investigación sobre la cacería, los cazadores campesinos permanecen con una baja representación en las revisiones comparativas de la cacería. Además, para el grupo más grande de cazadores en América Latina, no existen síntesis enfocadas en el estado actual del conocimiento sobre la cacería campesina, nada que guíe la investigación de la conservación y nada con qué practicarla. Revisamos 334 artículos publicados entre 1937 y 2018 en inglés (55%) y español (45%) - la mayoría publicados en 145 revistas revisadas por pares - que tratan sobre el significado, la motivación y la sustentabilidad de la cacería campesina en América Latina. Aunque los estudios abarcaron 17 países, siete ecosistemas y >75 demografías indígenas y no indígenas en 30 contextos de investigación, los artículos se enfocaron predominantemente en campesinos no indígenas para la conservación específica por especie y el manejo de las áreas protegidas en los bosques tropicales de México, Perú y Colombia. Los autores usaron doce métodos para recolectar datos de cacería campesina, principalmente entrevistas, encuestas y cuestionarios, y partieron de diez temas de conocimiento local y tradicional (CLT) sobre las tendencias y usos de la fauna. Dieciocho conductores, 14 restricciones, y diez conflictos - principalmente subsistencia, ingresos, ética, regulaciones y protección de cultivos o ganado - dieron forma a las decisiones de los cazadores sobre si perseguían a 799 especies, 70% de las cuales son especies de menor preocupación. Sin embargo, sólo 25 estudios (8%) evaluaron empíricamente la sustentabilidad. Nuestros resultados resaltan la necesidad de un mayor compromiso geográfico e interdisciplinario con la cacería campesina en toda América Latina.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Animales , Colombia , América Latina , México , Perú
7.
Toxicol Appl Pharmacol ; 367: 71-81, 2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30768972

RESUMEN

Polychlorinated biphenyls (PCBs) are persistent organic pollutants that contribute to inflammatory diseases such as atherosclerosis, and macrophages play a key role in the overall inflammatory response. Depending on specific environmental stimuli, macrophages can be polarized either to pro-inflammatory (e.g., M1) or anti-inflammatory (e.g., M2) phenotypes. We hypothesize that dioxin-like PCBs can contribute to macrophage polarization associated with inflammation. To test this hypothesis, human monocytes (THP-1) were differentiated to macrophages and subsequently exposed to PCB 126. Exposure to PCB 126, but not to PCB 153 or 118, significantly induced the expression of inflammatory cytokines, including TNFα and IL-1ß, suggesting polarization to the pro-inflammatory M1 phenotype. Additionally, monocyte chemoattractant protein-1 (MCP-1) was increased in PCB 126-activated macrophages, suggesting induction of chemokines which regulate immune cell recruitment and infiltration of monocytes/macrophages into vascular tissues. In addition, oxidative stress sensitive markers including nuclear factor (erythroid-derived 2)-like 2 (NFE2L2; Nrf2) and down-stream genes, such as heme oxygenase 1 (HMOX1) and NAD(P)H quinone oxidoreductase 1 (NQO1), were induced following PCB 126 exposure. Since dioxin-like PCBs may elicit inflammatory cascades through multiple mechanisms, we then pretreated macrophages with both aryl hydrocarbon receptor (AhR) and NF-κB antagonists prior to PCB treatment. The NF-κB antagonist BMS-345541 significantly decreased mRNA and protein levels of multiple cytokines by approximately 50% compared to PCB treatment alone, but the AhR antagonist CH-223191 was protective to a lesser degree. Our data demonstrate the involvement of PCB 126 in macrophage polarization and inflammation, indicating another important role of dioxin-like PCBs in the pathology of atherosclerosis.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/agonistas , Diferenciación Celular/efectos de los fármacos , Citocinas/metabolismo , Mediadores de Inflamación/metabolismo , Inflamación/inducido químicamente , Macrófagos/efectos de los fármacos , FN-kappa B/metabolismo , Bifenilos Policlorados/toxicidad , Receptores de Hidrocarburo de Aril/agonistas , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Humanos , Inflamación/metabolismo , Inflamación/patología , Macrófagos/metabolismo , Macrófagos/patología , Fenotipo , Receptores de Hidrocarburo de Aril/metabolismo , Transducción de Señal/efectos de los fármacos , Células THP-1
8.
Environ Res ; 162: 211-218, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29353125

RESUMEN

Trimethylamine N-oxide (TMAO) is a diet and gut microbiota-derived metabolite that has been linked to cardiovascular disease risk in human studies and animal models. TMAO levels show wide inter and intra individual variability in humans that can likely be accounted for by multiple factors including diet, the gut microbiota, levels of the TMAO generating liver enzyme Flavin-containing monooxygenase 3 (FMO3) and kidney function. We recently found that dioxin-like (DL) environmental pollutants increased FMO3 expression to elevate circulating diet-derived TMAO in mice, suggesting that exposure to this class of pollutants might also contribute to inter-individual variability in circulating TMAO levels in humans. To begin to explore this possibility we examined the relationship between body burden of DL pollutants (reported by serum lipid concentrations) and serum TMAO levels (n = 340) in the Anniston, AL cohort, which was highly exposed to polychlorinated biphenyls (PCBs). TMAO concentrations in archived serum samples from the Anniston Community Health Survey (ACHS-II) were measured, and associations of TMAO with 28 indices of pollutant body burden, including total dioxins toxic equivalent (TEQ), were quantified. Twenty-three (22 after adjustment for multiple comparisons) of the 28 indices were significantly positively associated with TMAO. Although the design of ACHS-II does not enable quantitative assessment of the contributions of previously known determinants of TMAO variability to this relationship, limited multivariate modeling revealed that total dioxins TEQ was significantly associated with TMAO among females (except at high BMIs) but not among males. Our results from this cross-sectional study indicate that exposure to DL pollutants may contribute to elevated serum TMAO levels. Prospective longitudinal studies will be required to assess the joint relationship between DL pollutant exposures, other determinants of TMAO, and health outcomes.


Asunto(s)
Dioxinas , Contaminantes Ambientales , Metilaminas , Obesidad Mórbida , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Animales , Estudios Transversales , Dioxinas/toxicidad , Femenino , Humanos , Masculino , Metilaminas/sangre , Ratones , Bifenilos Policlorados/toxicidad , Dibenzodioxinas Policloradas/toxicidad , Estudios Prospectivos
10.
Toxicol Appl Pharmacol ; 289(3): 457-65, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26519613

RESUMEN

Epigenetic modifications of DNA and histones alter cellular phenotypes without changing genetic codes. Alterations of epigenetic marks can be induced by exposure to environmental pollutants and may contribute to associated disease risks. Here we test the hypothesis that endothelial cell dysfunction induced by exposure to polychlorinated biphenyls (PCBs) is mediated in part though histone modifications. In this study, human vascular endothelial cells were exposed to physiologically relevant concentrations of several PCBs congeners (e.g., PCBs 77, 118, 126 and 153) followed by quantification of inflammatory gene expression and changes of histone methylation. Only exposure to coplanar PCBs 77 and 126 induced the expression of histone H3K9 trimethyl demethylase jumonji domain-containing protein 2B (JMJD2B) and nuclear factor-kappa B (NF-κB) subunit p65, activated NF-κB signaling as evidenced by nuclear translocation of p65, and up-regulated p65 target inflammatory genes, such as interleukin (IL)-6, C-reactive protein (CRP), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and IL-1α/ß. The increased accumulation of JMJD2B in the p65 promoter led to a depletion of H3K9me3 repression mark, which accounts for the observed up-regulation of p65 and associated inflammatory genes. JMJD2B gene knockdown confirmed a critical role for this histone demethylase in mediating PCB-induced inflammation of the vascular endothelium. Finally, it was determined, via chemical inhibition, that PCB-induced up-regulation of JMJD2B was estrogen receptor-alpha (ER-α) dependent. These data suggest that coplanar PCBs may exert endothelial cell toxicity through changes in histone modifications.


Asunto(s)
Células Endoteliales/efectos de los fármacos , Contaminantes Ambientales/efectos adversos , Epigénesis Genética/efectos de los fármacos , Inflamación/inducido químicamente , FN-kappa B/genética , Bifenilos Policlorados/efectos adversos , eIF-2 Quinasa/genética , Proteína C-Reactiva/genética , Adhesión Celular/efectos de los fármacos , Adhesión Celular/genética , Células Cultivadas , Endotelio Vascular/efectos de los fármacos , Epigénesis Genética/genética , Histonas/genética , Humanos , Inflamación/genética , Molécula 1 de Adhesión Intercelular/genética , Interleucina-6/genética , Metilación/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Factor de Necrosis Tumoral alfa/genética , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/genética , Molécula 1 de Adhesión Celular Vascular/genética
11.
Toxicol Appl Pharmacol ; 277(2): 192-9, 2014 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-24709675

RESUMEN

Environmental toxicants such as polychlorinated biphenyls (PCBs) have been implicated in the promotion of multiple inflammatory disorders including cardiovascular disease, but information regarding mechanisms of toxicity and cross-talk between relevant cell signaling pathways is lacking. To examine the hypothesis that cross-talk between membrane domains called caveolae and nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathways alters PCB-induced inflammation, caveolin-1 was silenced in vascular endothelial cells, resulting in a decreased PCB-induced inflammatory response. Cav-1 silencing (siRNA treatment) also increased levels of Nrf2-ARE transcriptional binding, resulting in higher mRNA levels of the antioxidant genes glutathione s-transferase and NADPH dehydrogenase quinone-1 in both vehicle and PCB-treated systems. Along with this upregulated antioxidant response, Cav-1 siRNA treated cells exhibited decreased mRNA levels of the Nrf2 inhibitory protein Keap1 in both vehicle and PCB-treated samples. Silencing Cav-1 also decreased protein levels of Nrf2 inhibitory proteins Keap1 and Fyn kinase, especially in PCB-treated cells. Further, endothelial cells from wildtype and Cav-1-/- mice were isolated and treated with PCB to better elucidate the role of functional caveolae in PCB-induced endothelial inflammation. Cav-1-/- endothelial cells were protected from PCB-induced cellular dysfunction as evidenced by decreased vascular cell adhesion molecule (VCAM-1) protein induction. Compared to wildtype cells, Cav-1-/- endothelial cells also allowed for a more effective antioxidant response, as observed by higher levels of the antioxidant genes. These data demonstrate novel cross-talk mechanisms between Cav-1 and Nrf2 and implicate the reduction of Cav-1 as a protective mechanism for PCB-induced cellular dysfunction and inflammation.


Asunto(s)
Caveolas/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Factor 2 Relacionado con NF-E2/metabolismo , Bifenilos Policlorados/toxicidad , Transducción de Señal/efectos de los fármacos , Animales , Caveolas/metabolismo , Caveolas/patología , Caveolina 1/genética , Caveolina 1/metabolismo , Línea Celular , Células Endoteliales/metabolismo , Células Endoteliales/patología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Glutatión Transferasa/genética , Glutatión Transferasa/metabolismo , Humanos , Mediadores de Inflamación/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , NADH Deshidrogenasa/genética , NADH Deshidrogenasa/metabolismo , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Interferencia de ARN , ARN Mensajero/metabolismo , Porcinos , Transfección , Molécula 1 de Adhesión Celular Vascular/metabolismo
12.
Environ Int ; 186: 108577, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38521043

RESUMEN

Male fertility has been declining worldwide especially in countries with high levels of endocrine disrupting chemicals (EDCs). Per- and polyfluorinated alkyl Substances (PFAS) have been classified as EDCs and have been linked to adverse male reproductive health. The mechanisms of these associations and their implications on offspring health remain unknown. The aims of the current study were to assess the effect of PFAS mixtures on the sperm methylome and transcriptional changes in offspring metabolic tissues (i.e., liver and fat). C57BL/6 male mice were exposed to a mixture of PFAS (PFOS, PFOA, PFNA, PFHxS, Genx; 20 µg/L each) for 18-weeks or water as a control. Genome-wide methylation was assessed on F0 epidydimal sperm using reduced representation bisulfite sequencing (RRBS) and Illumina mouse methylation array, while gene expression was assessed by bulk RNA sequencing in 8-week-old offspring derived from unexposed females. PFAS mixtures resulted in 2,861 (RRBS) and 83 (Illumina) sperm DMRs (q < 0.05). Functional enrichment revealed that PFAS-induced sperm DMRs were associated with behavior and developmental pathways in RRBS, while Illumina DMRs were related to lipid metabolism and cell signaling. Additionally, PFAS mixtures resulted in 40 and 53 differentially expressed genes (DEGs) in the liver and fat of males, and 9 and 31 DEGs in females, respectively. Functional enrichment of DEGs revealed alterations in cholesterol metabolism and mitotic cell cycle regulation in the liver and myeloid leukocyte migration in fat of male offspring, while in female offspring, erythrocyte development and carbohydrate catabolism were affected in fat. Our results demonstrate that exposure to a mixture of legacy and newly emerging PFAS chemicals in adult male mice result in aberrant sperm methylation and altered gene expression of offspring liver and fat in a sex-specific manner. These data indicate that preconception PFAS exposure in males can be transmitted to affect phenotype in the next generation.


Asunto(s)
Metilación de ADN , Fluorocarburos , Hígado , Ratones Endogámicos C57BL , Espermatozoides , Transcriptoma , Animales , Masculino , Hígado/efectos de los fármacos , Hígado/metabolismo , Espermatozoides/efectos de los fármacos , Ratones , Transcriptoma/efectos de los fármacos , Fluorocarburos/toxicidad , Femenino , Metilación de ADN/efectos de los fármacos , Disruptores Endocrinos/toxicidad , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Contaminantes Ambientales/toxicidad
13.
JAMA Netw Open ; 7(4): e245742, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38598238

RESUMEN

Importance: Evidence suggests that living near green space supports mental health, but studies examining the association of green space with early mental health symptoms among children are rare. Objective: To evaluate the association between residential green space and early internalizing (eg, anxiety and depression) and externalizing (eg, aggression and rule-breaking) symptoms. Design, Setting, and Participants: Data for this cohort study were drawn from the Environmental Influences on Child Health Outcomes cohort; analysis was conducted from July to October 2023. Children born between 2007 and 2013 with outcome data in early (aged 2-5 years) and/or middle (aged 6-11 years) childhood who resided in 41 states across the US, drawing from clinic, hospital, and community-based cohorts, were included. Cohort sites were eligible if they recruited general population participants and if at least 30 children had outcome and residential address data to measure green space exposure. Nine cohorts with 13 sites met these criteria. Children diagnosed with autism or developmental delay were excluded, and 1 child per family was included. Exposures: Green space exposure was measured using a biannual (ie, summer and winter) Normalized Difference Vegetation Index, a satellite image-based indicator of vegetation density assigned to monthly residential history from birth to outcome assessment. Main Outcome and Measures: Child internalizing and externalizing symptoms were assessed using the Child Behavior Checklist for Ages 1½ to 5 or 6 to 18. The association between green space and internalizing and externalizing symptoms was modeled with multivariable linear regression using generalized estimating equations, adjusting for birthing parent educational level, age at delivery, child sex, prematurity, and neighborhood socioeconomic vulnerability. Models were estimated separately for early and middle childhood samples. Results: Among 2103 children included, 1061 (50.5%) were male; 606 (29.1%) identified as Black, 1094 (52.5%) as White, 248 (11.9%) as multiple races, and 137 (6.6%) as other races. Outcomes were assessed at mean (SD) ages of 4.2 (0.6) years in 1469 children aged 2 to 5 years and 7.8 (1.6) years in 1173 children aged 6 to 11 years. Greater green space exposure was associated with fewer early childhood internalizing symptoms in fully adjusted models (b = -1.29; 95% CI, -1.62 to -0.97). No associations were observed between residential green space and internalizing or externalizing symptoms in middle childhood. Conclusions and Relevance: In this study of residential green space and children's mental health, the association of green space with fewer internalizing symptoms was observed only in early childhood, suggesting a sensitive period for nature exposure. Policies protecting and promoting access to green space may help alleviate early mental health risk.


Asunto(s)
Agresión , Parques Recreativos , Niño , Humanos , Preescolar , Masculino , Femenino , Estudios de Cohortes , Instituciones de Atención Ambulatoria , Ansiedad/epidemiología
14.
Environ Toxicol Pharmacol ; 98: 104062, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36621559

RESUMEN

Exposure to certain per-and polyfluoroalkyl substances (PFAS) has been shown to be positively associated with total and/or low-density lipoprotein cholesterol. Examining this association in lipid lowering interventions may provide additional evidence linking PFAS to cardiovascular risk. We examined the relationship of 6 PFAS with cholesterol in a 6-month lifestyle-based intervention. We quantitated PFAS in 350 individuals at baseline and post intervention and examined associations of PFAS with cholesterol before and after intervention. Food frequency questionnaires and GIS analyses were used to investigate PFAS hotspots and possible exposure routes. Cholesterol significantly decreased following intervention and in parallel, PFOS, PFOA, PFHxS, and PFHpA significantly decreased. PFOS was positively correlated with total cholesterol only post-intervention. We observed that PFOS was distributed among both non-albumin and albumin lipoprotein fractions pre-intervention, but entirely in albumin fraction post-intervention. Our results indicate that lipid-lowering via lifestyle modification may impact on circulating levels or distribution of PFAS.


Asunto(s)
Ácidos Alcanesulfónicos , Contaminantes Ambientales , Fluorocarburos , Humanos , Colesterol , LDL-Colesterol , Estilo de Vida
15.
Reprod Toxicol ; 118: 108384, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37061048

RESUMEN

The gut microbiota plays an important role throughout the lifespan in maintaining host health, and several factors can modulate microbiota composition including diet, exercise, and environmental exposures. Maternal microbiota is transferred to offspring during early life; thus, environmental exposures before gestation may also modulate offspring microbiota. Here we aimed to investigate the effects of maternal exposure to dioxin-like polychlorinated biphenyls (PCBs) on the microbiota of aged offspring and to determine if lifestyle factors, including maternal exercise or offspring high-fat feeding alter these associations. To test this, dams were exposed to PCB 126 (0.5 µmole/kg body weight) or vehicle oil by oral gavage during preconception, gestation, and during lactation. Half of each group was allowed access to running wheels for ≥ 7 days before and during pregnancy and up through day 14 of lactation. Female offspring born from the 4 maternal groups (PCB exposure or not, with/without exercise) were subsequently placed either on regular diet or switched to a high-fat diet during adulthood. Microbiota composition was quantified in female offspring at 49 weeks of age by 16 S rRNA sequencing. Maternal exposure to PCB 126 resulted in significantly reduced richness and diversity in offspring microbiota regardless of diet or exercise. Overall compositional differences were largely driven by offspring diet, but alterations in specific taxa due to maternal PCB 126 exposure, included the depletion of Verrucomicrobiaceae and Akkermansia muciniphila, and an increase in Anaeroplasma. Perturbation of microbiota due to PCB 126 may predispose offspring to a variety of chronic diseases later in adulthood.


Asunto(s)
Microbioma Gastrointestinal , Bifenilos Policlorados , Efectos Tardíos de la Exposición Prenatal , Embarazo , Femenino , Humanos , Anciano , Bifenilos Policlorados/toxicidad , Exposición Materna/efectos adversos , Dieta Alta en Grasa
16.
iScience ; 26(4): 106287, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37153445

RESUMEN

Maternal immune activation (MIA) by environmental challenges is linked to severe developmental complications, such as neurocognitive disorders, autism, and even fetal/maternal death. Benzene is a major toxic compound in air pollution that affects the mother as well as the fetus and has been associated with reproductive complications. Our objective was to elucidate whether benzene exposure during gestation triggers MIA and its impact on fetal development. We report that benzene exposure during pregnancy leads MIA associated with increased fetal resorptions, fetal growth, and abnormal placenta development. Furthermore, we demonstrate the existence of a sexual dimorphic response to benzene exposure in male and female placentas. The sexual dimorphic response is a consequence of inherent differences between male and female placenta. These data provide crucial information on the origins or sexual dimorphism and how exposure to environmental factors can have a differential impact on the development of male and female offspring.

17.
Artículo en Inglés | MEDLINE | ID: mdl-37510572

RESUMEN

Tools for assessing multiple exposures across several domains (e.g., physical, chemical, and social) are of growing importance in social and environmental epidemiology because of their value in uncovering disparities and their impact on health outcomes. Here we describe work done within the Environmental influences on Child Health Outcomes (ECHO)-wide Cohort Study to build a combined exposure index. Our index considered both environmental hazards and social stressors simultaneously with national coverage for a 10-year period. Our goal was to build this index and demonstrate its utility for assessing differences in exposure for pregnancies enrolled in the ECHO-wide Cohort Study. Our unitless combined exposure index, which collapses census-tract level data into a single relative measure of exposure ranging from 0-1 (where higher values indicate higher exposure to hazards), includes indicators for major air pollutants and air toxics, features of the built environment, traffic exposures, and social determinants of health (e.g., lower educational attainment) drawn from existing data sources. We observed temporal and geographic variations in index values, with exposures being highest among participants living in the West and Northeast regions. Pregnant people who identified as Black or Hispanic (of any race) were at higher risk of living in a "high" exposure census tract (defined as an index value above 0.5) relative to those who identified as White or non-Hispanic. Index values were also higher for pregnant people with lower educational attainment. Several recommendations follow from our work, including that environmental and social stressor datasets with higher spatial and temporal resolutions are needed to ensure index-based tools fully capture the total environmental context.


Asunto(s)
Contaminantes Atmosféricos , Femenino , Humanos , Embarazo , Contaminantes Atmosféricos/análisis , Estudios de Cohortes , Exposición a Riesgos Ambientales/análisis , Salud Ambiental , Hispánicos o Latinos , Evaluación de Resultado en la Atención de Salud , Blanco , Negro o Afroamericano
18.
Front Endocrinol (Lausanne) ; 13: 965384, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35992116

RESUMEN

Per- and polyfluoroalkyl substances (PFAS) are ubiquitous man-made chemicals found in consumer products including fabrics, food packaging, non-stick coatings, and aqueous film-forming foams. PFAS are stable and extremely resistant to degradation, resulting in high persistence throughout the environment as well as in human blood. PFAS consist of a large family of synthetic chemicals, with over 4000 distinct varieties having been identified and around 250 currently being manufactured at globally relevant levels. Numerous epidemiological studies have linked exposure to PFAS with adverse health effects ranging from immunotoxicity, cardiometabolic disease, developmental and reproductive effects, cancer, and recently type 2 diabetes. Several studies have demonstrated associations between serum PFAS concentrations and glycemic indicators of type 2 diabetes including glucose, insulin, and HOMA-IR in adolescent and adult cohorts. In addition, some studies have shown positive associations with incident type 2 diabetes and multiple PFAS. However, the link between PFAS exposure and the development of diabetes continues to be a disputed area of study, with conflicting data having been reported from various epidemiological studies. In this mini review we will summarize the current state of the literature linking PFAS to type 2 diabetes and discuss important future directions including the use of more complex mixtures-based statistical analyses.


Asunto(s)
Diabetes Mellitus Tipo 2 , Fluorocarburos , Adolescente , Adulto , Glucemia , Diabetes Mellitus Tipo 2/inducido químicamente , Diabetes Mellitus Tipo 2/epidemiología , Fluorocarburos/toxicidad , Humanos , Reproducción
19.
Toxics ; 10(2)2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35202247

RESUMEN

The hepatic xenobiotic metabolizing enzyme flavin-containing monooxygenase 3 (FMO3) has been implicated in the development of cardiometabolic disease primarily due to its enzymatic product trimethylamine-N oxide (TMAO), which has recently been shown to be associated with multiple chronic diseases, including kidney and coronary artery diseases. Although TMAO may have causative roles as a pro-inflammatory mediator, the possibility for roles in metabolic disease for FMO3, irrespective of TMAO formation, does exist. We hypothesized that FMO3 may interact with other proteins known to be involved in cardiometabolic diseases and that modulating the expression of FMO3 may impact on these interaction partners. Here, we combine a co-immunoprecipitation strategy coupled to unbiased proteomic workflow to report a novel protein:protein interaction network for FMO3. We identified 51 FMO3 protein interaction partners, and through gene ontology analysis, have identified urea cycle as an enriched pathway. Using mice deficient in FMO3 on two separate backgrounds, we validated and further investigated expressional and functional associations between FMO3 and the identified urea cycle genes. FMO3-deficient mice showed hepatic overexpression of carbamoylphosphate synthetase (CPS1), the rate-limiting gene of urea cycle, and increased hepatic urea levels, especially in mice of FVB (Friend leukemia virus B strain) background. Finally, overexpression of FMO3 in murine AML12 hepatocytes led to downregulation of CPS1. Although there is past literature linking TMAO to urea cycle, this is the first published work showing that FMO3 and CPS1 may directly interact, implicating a role for FMO3 in chronic kidney disease irrespective of TMAO formation.

20.
Toxics ; 10(6)2022 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-35736936

RESUMEN

Exposure to environmental pollutants, including dioxin-like polychlorinated biphenyls (PCBs), play an important role in vascular inflammation and cardiometabolic diseases (CMDs) by inducing oxidative stress. Earlier, we demonstrated that oxidative stress-mediated lipid peroxidation derived 4-hydroxy-2-nonenal (4HNE) contributes to CMDs by decreasing the angiogenesis of coronary endothelial cells (CECs). By detoxifying 4HNE, aldehyde dehydrogenase 2 (ALDH2), a mitochondrial enzyme, enhances CEC angiogenesis. Therefore, we hypothesize that ALDH2 activation attenuates a PCB 126-mediated 4HNE-induced decrease in CEC angiogenesis. To test our hypothesis, we treated cultured mouse CECs with 4.4 µM PCB 126 and performed spheroid and aortic ring sprouting assays, the ALDH2 activity assay, and Western blotting for the 4HNE adduct levels and real-time qPCR to determine the expression levels of Cyp1b1 and oxidative stress-related genes. PCB 126 increased the gene expression and 4HNE adduct levels, whereas it decreased the ALDH2 activity and angiogenesis significantly in MCECs. However, pretreatment with 2.5 µM disulfiram (DSF), an ALDH2 inhibitor, or 10 µM Alda 1, an ALDH2 activator, before the PCB 126 challenge exacerbated and rescued the PCB 126-mediated decrease in coronary angiogenesis by modulating the 4HNE adduct levels respectively. Finally, we conclude that ALDH2 can be a therapeutic target to alleviate environmental pollutant-induced CMDs.

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