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1.
Small ; : e2303072, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37438678

RESUMO

Pregnancy is a vulnerable life stage for the mother and developing fetus. Because of this dual concern, approved therapeutic options for pre-existing conditions or pregnancy-induced pathologies, placental deformities, or fetal concerns are extremely limited. These cases often leave patients and clinicians having to choose between maternal health and fetal development. Recent advancements in nanomedicine and nanotherapeutic devices have made the development of perinatal therapeutics an attractive objective. However, perinatal medicine requires a multifaceted approach given the interactions between maternal, placental, and fetal physiology. Maternal-fetal interactions are centralized to the placenta, a specialized transient barrier organ, to allow for nutrient and waste exchange. Perinatal nanotherapeutics must be designed for placental avoidance or uptake. In this review, pregnancy-related conditions, experimental models, and modes of drug delivery during pregnancy are discussed.

2.
Part Fibre Toxicol ; 20(1): 16, 2023 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-37088832

RESUMO

BACKGROUND: Exposure to micro- and nanoplastic particles (MNPs) in humans is being identified in both the indoor and outdoor environment. Detection of these materials in the air has made inhalation exposure to MNPs a major cause for concern. One type of plastic polymer found in indoor and outdoor settings is polyamide, often referred to as nylon. Inhalation of combustion-derived, metallic, and carbonaceous aerosols generate pulmonary inflammation, cardiovascular dysfunction, and systemic inflammation. Additionally, due to the additives present in plastics, MNPs may act as endocrine disruptors. Currently there is limited knowledge on potential health effects caused by polyamide or general MNP inhalation. OBJECTIVE: The purpose of this study is to assess the toxicological consequences of a single inhalation exposure of female rats to polyamide MNP during estrus by means of aerosolization of MNP. METHODS: Bulk polyamide powder (i.e., nylon) served as a representative MNP. Polyamide aerosolization was characterized using particle sizers, cascade impactors, and aerosol samplers. Multiple-Path Particle Dosimetry (MPPD) modeling was used to evaluate pulmonary deposition of MNPs. Pulmonary inflammation was assessed by bronchoalveolar lavage (BAL) cell content and H&E-stained tissue sections. Mean arterial pressure (MAP), wire myography of the aorta and uterine artery, and pressure myography of the radial artery was used to assess cardiovascular function. Systemic inflammation and endocrine disruption were quantified by measurement of proinflammatory cytokines and reproductive hormones. RESULTS: Our aerosolization exposure platform was found to generate particles within the micro- and nano-size ranges (thereby constituting MNPs). Inhaled particles were predicted to deposit in all regions of the lung; no overt pulmonary inflammation was observed. Conversely, increased blood pressure and impaired dilation in the uterine vasculature was noted while aortic vascular reactivity was unaffected. Inhalation of MNPs resulted in systemic inflammation as measured by increased plasma levels of IL-6. Decreased levels of 17ß-estradiol were also observed suggesting that MNPs have endocrine disrupting activity. CONCLUSIONS: These data demonstrate aerosolization of MNPs in our inhalation exposure platform. Inhaled MNP aerosols were found to alter inflammatory, cardiovascular, and endocrine activity. These novel findings will contribute to a better understanding of inhaled plastic particle toxicity.


Assuntos
Nylons , Pneumonia , Humanos , Ratos , Feminino , Animais , Ratos Sprague-Dawley , Nylons/toxicidade , Microplásticos , Exposição por Inalação/efeitos adversos , Exposição por Inalação/análise , Dilatação , Aerossóis e Gotículas Respiratórios , Pneumonia/induzido quimicamente , Pulmão , Inflamação/induzido quimicamente , Tamanho da Partícula , Líquido da Lavagem Broncoalveolar
3.
Am J Physiol Heart Circ Physiol ; 323(3): H475-H489, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35904886

RESUMO

The study of peripheral vasculopathy with chronic metabolic disease is challenged by divergent contributions from spatial (the level of resolution or specific tissue being studied) and temporal origins (evolution of the developing impairments in time). Over many years of studying the development of skeletal muscle vasculopathy and its functional implications, we may be at the point of presenting an integrated conceptual model that addresses these challenges within the obese Zucker rat (OZR) model. At the early stages of metabolic disease, where systemic markers of elevated cardiovascular disease risk are present, the only evidence of vascular dysfunction is at postcapillary and collecting venules, where leukocyte adhesion/rolling is elevated with impaired venular endothelial function. As metabolic disease severity and duration increases, reduced microvessel density becomes evident as well as increased variability in microvascular hematocrit. Subsequently, hemodynamic impairments to distal arteriolar networks emerge, manifesting as increasing perfusion heterogeneity and impaired arteriolar reactivity. This retrograde "wave of dysfunction" continues, creating a condition wherein deficiencies to the distal arteriolar, capillary, and venular microcirculation stabilize and impairments to proximal arteriolar reactivity, wall mechanics, and perfusion distribution evolve. This proximal arteriolar dysfunction parallels increasing failure in fatigue resistance, hyperemic responses, and O2 uptake within self-perfused skeletal muscle. Taken together, these results present a conceptual model for the retrograde development of peripheral vasculopathy with chronic metabolic disease and provide insight into the timing and targeting of interventional strategies to improve health outcomes.NEW & NOTEWORTHY Working from an established database spanning multiple scales and times, we studied progression of peripheral microvascular dysfunction in chronic metabolic disease. The data implicate the postcapillary venular endothelium as the initiating site for vasculopathy. Indicators of dysfunction, spanning network structures, hemodynamics, vascular reactivity, and perfusion progress in an insidious retrograde manner to present as functional impairments to muscle blood flow and performance much later. The silent vasculopathy progression may provide insight into clinical treatment challenges.


Assuntos
Doenças Metabólicas , Síndrome Metabólica , Doenças Vasculares Periféricas , Animais , Síndrome Metabólica/metabolismo , Microcirculação/fisiologia , Músculo Esquelético/irrigação sanguínea , Obesidade/complicações , Ratos , Ratos Zucker
4.
Part Fibre Toxicol ; 17(1): 55, 2020 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-33099312

RESUMO

BACKGROUND: Plastic is everywhere. It is used in food packaging, storage containers, electronics, furniture, clothing, and common single-use disposable items. Microplastic and nanoplastic particulates are formed from bulk fragmentation and disintegration of plastic pollution. Plastic particulates have recently been detected in indoor air and remote atmospheric fallout. Due to their small size, microplastic and nanoplastic particulate in the atmosphere can be inhaled and may pose a risk for human health, specifically in susceptible populations. When inhaled, nanosized particles have been shown to translocate across pulmonary cell barriers to secondary organs, including the placenta. However, the potential for maternal-to-fetal translocation of nanosized-plastic particles and the impact of nanoplastic deposition or accumulation on fetal health remain unknown. In this study we investigated whether nanopolystyrene particles can cross the placental barrier and deposit in fetal tissues after maternal pulmonary exposure. RESULTS: Pregnant Sprague Dawley rats were exposed to 20 nm rhodamine-labeled nanopolystyrene beads (2.64 × 1014 particles) via intratracheal instillation on gestational day (GD) 19. Twenty-four hours later on GD 20, maternal and fetal tissues were evaluated using fluorescent optical imaging. Fetal tissues were fixed for particle visualization with hyperspectral microscopy. Using isolated placental perfusion, a known concentration of nanopolystyrene was injected into the uterine artery. Maternal and fetal effluents were collected for 180 min and assessed for polystyrene particle concentration. Twenty-four hours after maternal exposure, fetal and placental weights were significantly lower (7 and 8%, respectively) compared with controls. Nanopolystyrene particles were detected in the maternal lung, heart, and spleen. Polystyrene nanoparticles were also observed in the placenta, fetal liver, lungs, heart, kidney, and brain suggesting maternal lung-to-fetal tissue nanoparticle translocation in late stage pregnancy. CONCLUSION: These studies confirm that maternal pulmonary exposure to nanopolystyrene results in the translocation of plastic particles to placental and fetal tissues and renders the fetoplacental unit vulnerable to adverse effects. These data are vital to the understanding of plastic particulate toxicology and the developmental origins of health and disease.


Assuntos
Poliestirenos/toxicidade , Animais , Feminino , Feto , Humanos , Exposição por Inalação , Exposição Materna , Troca Materno-Fetal , Tamanho da Partícula , Placenta , Plásticos , Poliestirenos/metabolismo , Gravidez , Ratos , Ratos Sprague-Dawley
5.
Microcirculation ; 26(8): e12526, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30597690

RESUMO

The Barker Hypothesis states change to the maternal environment may have significant impacts on fetal development, setting the stage for adult disease to occur. The development of the maternofetal vasculature during implantation and maintenance during pregnancy is extremely precise, yet dynamic. Delays or dysfunction in the orchestration of anatomical remodeling, maintenance of blood pressure, or responsiveness to metabolic demand may have severe consequences to the developing fetus. While these intermissions may not be fatal to the developing fetus, an interruption, reduction, or an inability to meet fetal demand of blood flow during crucial stages of development may predispose young to disease later in life. Maternal inability to meet fetal demand can be attributed to improper placental development and vascular support through morphological change or physiological function will significantly limit nutrient delivery and waste exchange to the developing fetus. Therefore, we present an overview of the uteroplacental vascular network, maternal cardiovascular adaptations that occur during pregnancy, placental blood flow, and common maternal comorbidities and/or exposures that may perturb maternal homeostasis and affect fetal development. Overall, we examine uterine microvasculature pathophysiology contributing to a hostile gestational environment and fetal predisposition to disease as it relates to the Barker Hypothesis.


Assuntos
Doenças Cardiovasculares/embriologia , Desenvolvimento Fetal , Feto/embriologia , Placenta/metabolismo , Animais , Doenças Cardiovasculares/patologia , Feminino , Feto/patologia , Humanos , Placenta/patologia , Gravidez
6.
Microcirculation ; 26(8): e12558, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31090984

RESUMO

Historically, major advances in microvascular research have been made by integrating physiology and bioengineering approaches. This Special Topics Issue focuses on providing a spotlight on emerging areas of microvascular research, showcasing how interdisciplinary collaborations and application of novel techniques can impact our understanding of tissue-specific microvascular remodeling by integrating cell behaviors across scales. The authors in this issue investigate pericyte physiology, perturbations to uteroplacental blood flow, bone microvascular alterations in aging, molecular markers of revascularization, and microfluidic devices to mimic the lymphatic system. The articles highlight the continued importance of expanding our understanding of the microvascular system in health, and disease extends microvascular boundaries in the face of current paradigms, and illustrates how emerging leaders in the field are creating new scientific niches.


Assuntos
Pesquisa Biomédica , Microcirculação , Microvasos , Animais , Humanos
7.
Am J Physiol Heart Circ Physiol ; 312(3): H446-H458, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28011589

RESUMO

Nanomaterial production is expanding as new industrial and consumer applications are introduced. Nevertheless, the impacts of exposure to these compounds are not fully realized. The present study was designed to determine whether gestational nano-sized titanium dioxide exposure impacts cardiac and metabolic function of developing progeny. Pregnant Sprague-Dawley rats were exposed to nano-aerosols (~10 mg/m3, 130- to 150-nm count median aerodynamic diameter) for 7-8 nonconsecutive days, beginning at gestational day 5-6 Physiological and bioenergetic effects on heart function and cardiomyocytes across three time points, fetal (gestational day 20), neonatal (4-10 days), and young adult (6-12 wk), were evaluated. Functional analysis utilizing echocardiography, speckle-tracking based strain, and cardiomyocyte contractility, coupled with mitochondrial energetics, revealed effects of nano-exposure. Maternal exposed progeny demonstrated a decrease in E- and A-wave velocities, with a 15% higher E-to-A ratio than controls. Myocytes isolated from exposed animals exhibited ~30% decrease in total contractility, departure velocity, and area of contraction. Bioenergetic analysis revealed a significant increase in proton leak across all ages, accompanied by decreases in metabolic function, including basal respiration, maximal respiration, and spare capacity. Finally, electron transport chain complex I and IV activities were negatively impacted in the exposed group, which may be linked to a metabolic shift. Molecular data suggest that an increase in fatty acid metabolism, uncoupling, and cellular stress proteins may be associated with functional deficits of the heart. In conclusion, gestational nano-exposure significantly impairs the functional capabilities of the heart through cardiomyocyte impairment, which is associated with mitochondrial dysfunction.NEW & NOTEWORTHY Cardiac function is evaluated, for the first time, in progeny following maternal nanomaterial inhalation. The findings indicate that exposure to nano-sized titanium dioxide (nano-TiO2) during gestation negatively impacts cardiac function and mitochondrial respiration and bioenergetics. We conclude that maternal nano-TiO2 inhalation contributes to adverse cardiovascular health effects, lasting into adulthood.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Coração/diagnóstico por imagem , Miocárdio/patologia , Nanoestruturas/toxicidade , Efeitos Tardios da Exposição Pré-Natal/patologia , Envelhecimento , Animais , Ecocardiografia , Complexo I de Transporte de Elétrons/efeitos dos fármacos , Complexo I de Transporte de Elétrons/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/efeitos dos fármacos , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Cardiopatias/induzido quimicamente , Cardiopatias/diagnóstico por imagem , Cardiopatias/patologia , Testes de Função Cardíaca , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Gravidez , Ratos , Ratos Sprague-Dawley , Titânio/toxicidade
8.
Am J Physiol Heart Circ Physiol ; 310(4): H488-504, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26702145

RESUMO

To determine the impact of progressive elevations in peripheral vascular disease (PVD) risk on microvascular function, we utilized eight rat models spanning "healthy" to "high PVD risk" and used a multiscale approach to interrogate microvascular function and outcomes: healthy: Sprague-Dawley rats (SDR) and lean Zucker rats (LZR); mild risk: SDR on high-salt diet (HSD) and SDR on high-fructose diet (HFD); moderate risk: reduced renal mass-hypertensive rats (RRM) and spontaneously hypertensive rats (SHR); high risk: obese Zucker rats (OZR) and Dahl salt-sensitive rats (DSS). Vascular reactivity and biochemical analyses demonstrated that even mild elevations in PVD risk severely attenuated nitric oxide (NO) bioavailability and caused progressive shifts in arachidonic acid metabolism, increasing thromboxane A2 levels. With the introduction of hypertension, arteriolar myogenic activation and adrenergic constriction were increased. However, while functional hyperemia and fatigue resistance of in situ skeletal muscle were not impacted with mild or moderate PVD risk, blood oxygen handling suggested an increasingly heterogeneous perfusion within resting and contracting skeletal muscle. Analysis of in situ networks demonstrated an increasingly stable and heterogeneous distribution of perfusion at arteriolar bifurcations with elevated PVD risk, a phenomenon that was manifested first in the distal microcirculation and evolved proximally with increasing risk. The increased perfusion distribution heterogeneity and loss of flexibility throughout the microvascular network, the result of the combined effects on NO bioavailability, arachidonic acid metabolism, myogenic activation, and adrenergic constriction, may represent the most accurate predictor of the skeletal muscle microvasculopathy and poor health outcomes associated with chronic elevations in PVD risk.


Assuntos
Microcirculação , Músculo Esquelético/irrigação sanguínea , Doenças Vasculares Periféricas/fisiopatologia , Animais , Arteríolas/fisiopatologia , Frutose/farmacologia , Hipertensão Renal/fisiopatologia , Músculo Esquelético/fisiopatologia , Óxido Nítrico/metabolismo , Consumo de Oxigênio/fisiologia , Perfusão , Ratos , Ratos Endogâmicos Dahl , Ratos Endogâmicos SHR , Ratos Sprague-Dawley , Ratos Zucker , Medição de Risco , Sódio na Dieta/farmacologia , Tromboxano A2/metabolismo
9.
J Toxicol Environ Health A ; 79(11): 447-52, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27092594

RESUMO

It is generally accepted that gestational xenobiotic exposures result in systemic consequences in the adult F1 generation. However, data on detailed behavioral and cognitive consequences remain limited. Using our whole-body nanoparticle inhalation facility, pregnant Sprague-Dawley rats (gestational day [GD] 7) were exposed 4 d/wk to either filtered air (control) or nano-titanium dioxide aerosols (nano-TiO2; count median aerodynamic diameter of 170.9 ± 6.4 nm, 10.4 ± 0.4 mg/m(3), 5 h/d) for 7.8 ± 0.5 d of the remaining gestational period. All rats received their final exposure on GD 20 prior to delivery. The calculated daily maternal deposition was 13.9 ± 0.5 µg. Subsequently, at 5 mo of age, behavior and cognitive functions of these pups were evaluated employing a standard battery of locomotion, learning, and anxiety tests. These assessments revealed significant working impairments, especially under maximal mnemonic challenge, and possible deficits in initial motivation in male F1 adults. Evidence indicates that maternal engineered nanomaterial exposure during gestation produces psychological deficits that persist into adulthood in male rats.


Assuntos
Cognição/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Atividade Motora/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Titânio/toxicidade , Animais , Feminino , Masculino , Exposição Materna , Gravidez , Ratos , Ratos Sprague-Dawley
10.
Am J Physiol Heart Circ Physiol ; 309(10): H1609-20, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26386111

RESUMO

The cardiovascular response to xenobiotic particle exposure has been increasingly studied over the last two decades, producing an extraordinary scope and depth of research findings. With the flourishing of nanotechnology, the term "xenobiotic particles" has expanded to encompass not only air pollution particulate matter (PM) but also anthropogenic particles, such as engineered nanomaterials (ENMs). Historically, the majority of research in these fields has focused on pulmonary exposure and the adverse physiological effects associated with a host inflammatory response or direct particle-tissue interactions. Because these hypotheses can neither account entirely for the deleterious cardiovascular effects of xenobiotic particle exposure nor their time course, the case for substantial neurological involvement is apparent. Indeed, considerable evidence suggests that not only is neural involvement a significant contributor but also a reality that needs to be investigated more thoroughly when assessing xenobiotic particle toxicities. Therefore, the scope of this review is several-fold. First, we provide a brief overview of the major anatomical components of the central and peripheral nervous systems, giving consideration to the potential biologic targets affected by inhaled particles. Second, the autonomic arcs and mechanisms that may be involved are reviewed. Third, the cardiovascular outcomes following neurological responses are discussed. Lastly, unique problems, future risks, and hurdles associated with xenobiotic particle exposure are discussed. A better understanding of these neural issues may facilitate research that in conjunction with existing research, will ultimately prevent the untoward cardiovascular outcomes associated with PM exposures and/or identify safe ENMs for the advancement of human health.


Assuntos
Poluentes Atmosféricos/farmacologia , Sistema Nervoso Autônomo/efeitos dos fármacos , Sistema Cardiovascular/efeitos dos fármacos , Sistema Nervoso Central/efeitos dos fármacos , Exposição por Inalação , Pulmão/efeitos dos fármacos , Nanoestruturas , Material Particulado/farmacologia , Xenobióticos/farmacologia , Sistema Nervoso Autônomo/fisiopatologia , Sistema Cardiovascular/inervação , Sistema Cardiovascular/fisiopatologia , Sistema Nervoso Central/fisiopatologia , Humanos , Inflamação , Pulmão/inervação , Pulmão/fisiopatologia
11.
Am J Physiol Heart Circ Physiol ; 309(12): H2017-30, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26497962

RESUMO

Throughout the United States, air pollution correlates with adverse health outcomes, and cardiovascular disease incidence is commonly increased following environmental exposure. In areas surrounding active mountaintop removal mines (MTM), a further increase in cardiovascular morbidity is observed and may be attributed in part to particulate matter (PM) released from the mine. The mitochondrion has been shown to be central in the etiology of many cardiovascular diseases, yet its roles in PM-related cardiovascular effects are not realized. In this study, we sought to elucidate the cardiac processes that are disrupted following exposure to mountaintop removal mining particulate matter (PM MTM). To address this question, we exposed male Sprague-Dawley rats to PM MTM, collected within one mile of an active MTM site, using intratracheal instillation. Twenty-four hours following exposure, we evaluated cardiac function, apoptotic indices, and mitochondrial function. PM MTM exposure elicited a significant decrease in ejection fraction and fractional shortening compared with controls. Investigation into the cellular impacts of PM MTM exposure identified a significant increase in mitochondrial-induced apoptotic signaling, as reflected by an increase in TUNEL-positive nuclei and increased caspase-3 and -9 activities. Finally, a significant increase in mitochondrial transition pore opening leading to decreased mitochondrial function was identified following exposure. In conclusion, our data suggest that pulmonary exposure to PM MTM increases cardiac mitochondrial-associated apoptotic signaling and decreases mitochondrial function concomitant with decreased cardiac function. These results suggest that increased cardiovascular disease incidence in populations surrounding MTM mines may be associated with increased cardiac cell apoptotic signaling and decreased mitochondrial function.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Poluição do Ar/efeitos adversos , Cardiopatias/induzido quimicamente , Doenças Mitocondriais/induzido quimicamente , Material Particulado/toxicidade , Animais , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Ecocardiografia , Exposição Ambiental , Monitoramento Ambiental , Cardiopatias/diagnóstico por imagem , Marcação In Situ das Extremidades Cortadas , Injeções Espinhais , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Doenças Mitocondriais/diagnóstico por imagem , Contração Miocárdica/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
12.
Microcirculation ; 20(2): 158-69, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22963349

RESUMO

OBJECTIVE: Air pollution PM is associated with cardiovascular morbidity and mortality. In Appalachia, PM from mining may represent a health burden to this sensitive population that leads the nation in cardiovascular disease, among others. Cardiovascular consequences following inhalation of PM(MTM) are unclear, but must be identified to establish causal effects. METHODS: PM was collected within 1 mile of an active MTM site in southern WV. The PM was extracted and was primarily <10 µm in diameter (PM10), consisting largely of sulfur (38%) and silica (24%). Adult male rats were IT with 300 µg PM(MTM) . Twenty-four hours following exposure, rats were prepared for intravital microscopy, or isolated arteriole experiments. RESULTS: PM(MTM) exposure blunted endothelium-dependent dilation in mesenteric and coronary arterioles by 26%, and 25%, respectively, as well as endothelium-independent dilation. In vivo, PM(MTM) exposure inhibited endothelium-dependent arteriolar dilation (60% reduction). α-adrenergic receptor blockade inhibited PVNS-induced vasoconstriction in exposed animals compared with sham. CONCLUSIONS: These data suggest that PM(MTM) exposure impairs microvascular function in disparate microvascular beds, through alterations in NO-mediated dilation and sympathetic nerve influences. Microvascular dysfunction may contribute to cardiovascular disease in regions with MTM sites.


Assuntos
Poluentes Atmosféricos/toxicidade , Minas de Carvão , Microcirculação/fisiologia , Material Particulado/toxicidade , Doenças Vasculares/etiologia , Animais , Região dos Apalaches , Arteríolas/fisiopatologia , Circulação Coronária/fisiologia , Endotélio Vascular/fisiopatologia , Masculino , Metais/toxicidade , Microscopia/métodos , Ratos , Ratos Sprague-Dawley , Circulação Esplâncnica/fisiologia , Doenças Vasculares/fisiopatologia
13.
Am J Obstet Gynecol ; 209(3): 227.e1-11, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23643573

RESUMO

OBJECTIVE: The continued development and use of engineered nanomaterials (ENM) has given rise to concerns over the potential for human health effects. Although the understanding of cardiovascular ENM toxicity is improving, one of the most complex and acutely demanding "special" circulations is the enhanced maternal system to support fetal development. The Barker hypothesis proposes that fetal development within a hostile gestational environment may predispose/program future sensitivity. Therefore, the objective of this study was 2-fold: (1) to determine whether maternal ENM exposure alters uterine and/or fetal microvascular function and (2) test the Barker hypothesis at the microvascular level. STUDY DESIGN: Pregnant (gestation day 10) Sprague-Dawley rats were exposed to nano-titanium dioxide aerosols (11.3 ± 0.039 mg/m(3)/hr, 5 hr/d, 8.2 ± 0.85 days) to evaluate the maternal and fetal microvascular consequences of maternal exposure. Microvascular tissue isolation (gestation day 20) and arteriolar reactivity studies (<150 µm passive diameter) of the uterine premyometrial and fetal tail arteries were conducted. RESULTS: ENM exposures led to significant maternal and fetal microvascular dysfunction, which was seen as robustly compromised endothelium-dependent and -independent reactivity to pharmacologic and mechanical stimuli. Isolated maternal uterine arteriolar reactivity was consistent with a metabolically impaired profile and hostile gestational environment that impacted fetal weight. The fetal microvessels that were isolated from exposed dams demonstrated significant impairments to signals of vasodilation specific to mechanistic signaling and shear stress. CONCLUSION: To our knowledge, this is the first report to provide evidence that maternal ENM inhalation is capable of influencing fetal health and that the Barker hypothesis is applicable at the microvascular level.


Assuntos
Feto/efeitos dos fármacos , Exposição Materna/efeitos adversos , Nanoestruturas/toxicidade , Animais , Endotélio Vascular/fisiologia , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Microcirculação/efeitos dos fármacos , Gravidez , Ratos , Ratos Sprague-Dawley , Titânio/toxicidade , Contração Uterina/efeitos dos fármacos , Útero/irrigação sanguínea , Útero/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
14.
Nanomaterials (Basel) ; 13(4)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36839088

RESUMO

Recent studies in experimental animals found that oral exposure to micro- and nano-plastics (MNPs) during pregnancy had multiple adverse effects on outcomes and progeny, although no study has yet identified the translocation of ingested MNPs to the placenta or fetal tissues, which might account for those effects. We therefore assessed the placental and fetal translocation of ingested nanoscale polystyrene MNPs in pregnant rats. Sprague Dawley rats (N = 5) were gavaged on gestational day 19 with 10 mL/kg of 250 µg/mL 25 nm carboxylated polystyrene spheres (PS25C) and sacrificed after 24 h. Hyperspectral imaging of harvested placental and fetal tissues identified abundant PS25C within the placenta and in all fetal tissues examined, including liver, kidney, heart, lung and brain, where they appeared in 10-25 µm clusters. These findings demonstrate that ingested nanoscale polystyrene MNPs can breach the intestinal barrier and subsequently the maternal-fetal barrier of the placenta to access the fetal circulation and all fetal tissues. Further studies are needed to assess the mechanisms of MNP translocation across the intestinal and placental barriers, the effects of MNP polymer, size and other physicochemical properties on translocation, as well as the potential adverse effects of MNP translocation on the developing fetus.

15.
Microcirculation ; 19(2): 126-42, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21951337

RESUMO

Xenobiotic particles can be considered in two genres: air pollution particulate matter and engineered nanoparticles. Particle exposures can occur in the greater environment, the workplace, and our homes. The majority of research in this field has, justifiably, focused on pulmonary reactions and outcomes. More recent investigations indicate that cardiovascular effects are capable of correlating with established mortality and morbidity epidemiological data following particle exposures. While the preliminary and general cardiovascular toxicology has been defined, the mechanisms behind these effects, specifically within the microcirculation, are largely unexplored. Therefore, the purpose of this review is several fold: first, a historical background on toxicological aspects of particle research is presented. Second, essential definitions, terminology, and techniques that may be unfamiliar to the microvascular scientist will be discussed. Third, the most current concepts and hypotheses driving cardiovascular research in this field will be reviewed. Lastly, potential future directions for the microvascular scientist will be suggested. Collectively speaking, microvascular research in the particle exposure field represents far more than a "niche." The immediate demand for basic, translational, and clinical studies is high and diverse. Microvascular scientists at all career stages are strongly encouraged to expand their research interests to include investigations associated with particle exposures.


Assuntos
Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/fisiopatologia , Microcirculação/efeitos dos fármacos , Material Particulado/efeitos adversos , Xenobióticos/efeitos adversos , Animais , Doenças Cardiovasculares/mortalidade , Humanos
16.
Int J Mol Sci ; 13(11): 13781-803, 2012 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-23203034

RESUMO

Engineered nanomaterials have been developed for widespread applications due to many highly unique and desirable characteristics. The purpose of this study was to assess pulmonary inflammation and subepicardial arteriolar reactivity in response to multi-walled carbon nanotube (MWCNT) inhalation and evaluate the time course of vascular alterations. Rats were exposed to MWCNT aerosols producing pulmonary deposition. Pulmonary inflammation via bronchoalveolar lavage and MWCNT translocation from the lungs to systemic organs was evident 24 h post-inhalation. Coronary arterioles were evaluated 24-168 h post-exposure to determine microvascular response to changes in transmural pressure, endothelium-dependent and -independent reactivity. Myogenic responsiveness, vascular smooth muscle reactivity to nitric oxide, and α-adrenergic responses all remained intact. However, a severe impact on endothelium-dependent dilation was observed within 24 h after MWCNT inhalation, a condition which improved, but did not fully return to control after 168 h. In conclusion, results indicate that MWCNT inhalation not only leads to pulmonary inflammation and cytotoxicity at low lung burdens, but also a low level of particle translocation to systemic organs. MWCNT inhalation also leads to impairments of endothelium-dependent dilation in the coronary microcirculation within 24 h, a condition which does not fully dissipate within 168 h. The innovations within the field of nanotechnology, while exciting and novel, can only reach their full potential if toxicity is first properly assessed.


Assuntos
Vasos Coronários/patologia , Endotélio Vascular/patologia , Nanotubos de Carbono/toxicidade , Acetilcolina/farmacologia , Administração por Inalação , Animais , Pressão Arterial/efeitos dos fármacos , Líquido da Lavagem Broncoalveolar , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/metabolismo , Dilatação Patológica , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Coração/anatomia & histologia , Coração/efeitos dos fármacos , Rim/patologia , Fígado/patologia , Pulmão/patologia , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Nitroprussiato/farmacologia , Tamanho do Órgão , Fenilefrina/farmacologia , Pneumonia/etiologia , Pneumonia/patologia , Ratos , Fatores de Tempo
17.
Toxicol Sci ; 188(2): 153-179, 2022 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-35686923

RESUMO

Phthalates are ubiquitous compounds known to leach from the plastic products that contain them. Due to their endocrine-disrupting properties, a wide range of studies have elucidated their effects on reproduction, metabolism, neurodevelopment, and growth. Additionally, their impacts during pregnancy and on the developing fetus have been extensively studied. Most recently, there has been interest in the impacts of phthalates on the placenta, a transient major endocrine organ critical to maintenance of the uterine environment and fetal development. Phthalate-induced changes in placental structure and function may have significant impacts on the course of pregnancy and ultimately, child health. Prior reviews have described the literature on phthalates and placental health; however to date, there has been no comprehensive, systematic review on this topic. Here, we review 35 papers (24 human and 11 animal studies) and summarize phthalate exposures in relation to an extensive set of placental measures. Phthalate-related alterations were reported for placental morphology, hormone production, vascularization, histopathology, and gene/protein expression. The most consistent changes were observed in vascular and morphologic endpoints, including cell composition. These changes have implications for pregnancy complications such as preterm birth and intrauterine growth restriction as well as potential ramifications for children's health. This comprehensive review of the literature, including common sources of bias, will inform the future work in this rapidly expanding field.


Assuntos
Ácidos Ftálicos , Nascimento Prematuro , Animais , Criança , Feminino , Humanos , Recém-Nascido , Modelos Animais , Ácidos Ftálicos/metabolismo , Ácidos Ftálicos/toxicidade , Placenta , Gravidez , Nascimento Prematuro/metabolismo
18.
Compr Physiol ; 11(3): 1871-1893, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34061977

RESUMO

Successful pregnancy and reproduction are dependent on adequate uterine blood flow, placental perfusion, and vascular responsivity to fetal demands. The ability to support pregnancy centers on systemic adaptation and endometrial preparation through decidualization, embryonic implantation, trophoblast invasion, arterial/arteriolar reactivity, and vascular remodeling. These adaptations occur through responsiveness to endocrine signaling and local uteroplacental mediators. The purpose of this article is to highlight the current knowledge associated with vascular remodeling and responsivity during uterine preparation for and during pregnancy. We focus on maternal cardiovascular systemic and uterine modifications, endometrial decidualization, implantation and invasion, uterine and spiral artery remodeling, local uterine regulatory mechanisms, placentation, and pathological consequences of vascular dysfunction during pregnancy. © 2021 American Physiological Society. Compr Physiol 11:1-23, 2021.


Assuntos
Placenta , Placentação , Feminino , Humanos , Circulação Placentária , Gravidez , Trofoblastos , Remodelação Vascular
19.
Sci Rep ; 11(1): 19374, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34588535

RESUMO

Maternal exposure to environmental contaminants during pregnancy can profoundly influence the risk of developing cardiovascular disease in adult offspring. Our previous studies have demonstrated impaired cardiovascular health, microvascular reactivity, and cardiac function in fetal and young adult progeny after maternal inhalation of nano-sized titanium dioxide (nano-TiO2) aerosols during gestation. The present study was designed to evaluate the development of cardiovascular and metabolic diseases later in adulthood. Pregnant Sprague-Dawley rats were exposed to nano-TiO2 aerosols (~ 10 mg/m3, 134 nm median diameter) for 4 h per day, 5 days per week, beginning on gestational day (GD) 4 and ending on GD 19. Progeny were delivered in-house. Body weight was recorded weekly after birth. After 47 weeks, the body weight of exposed progeny was 9.4% greater compared with controls. Heart weight, mean arterial pressure, and plasma biomarkers of inflammation, dyslipidemia, and glycemic control were recorded at 3, 9 and 12 months of age, with no significant adaptations. While no clinical risk factors (i.e., hypertension, dyslipidemia, or systemic inflammation) emerged pertaining to the development of cardiovascular disease, we identified impaired endothelium-dependent and -independent arteriolar dysfunction and cardiac morphological alterations consistent with myocardial inflammation, degeneration, and necrosis in exposed progeny at 12 months. In conclusion, maternal inhalation of nano-TiO2 aerosols during gestation may promote the development of coronary disease in adult offspring.


Assuntos
Poluentes Atmosféricos/toxicidade , Cardiopatias/induzido quimicamente , Exposição Materna/efeitos adversos , Nanoestruturas/toxicidade , Titânio/toxicidade , Administração por Inalação , Animais , Animais Recém-Nascidos , Feminino , Exposição por Inalação , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley
20.
Physiol Genomics ; 42(3): 331-41, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20530721

RESUMO

One clinical intervention against the negative outcomes associated with atherothrombotic vascular disease (AVD) is low-dose, chronic aspirin therapy. However, epidemiological studies suggest that recurrence of adverse vascular events with aspirin therapy is growing and associated with therapy duration. The contributors to this outcome are unclear and include poor patient compliance and aspirin-resistant platelet thromboxane A(2) (TxA(2)) production. Based on previous results in hypercholesterolemic mice, we hypothesized that elevated aspirin-insensitive arachidonic acid (AA)-induced TxA(2) production by the vascular endothelium contributes to aspirin resistance in AVD independent of platelet behavior. AA-induced dilation was blunted in aortic rings and in arterioles from apolipoprotein E (ApoE) and low-density lipoprotein receptor (LDLR) gene deletion mice (vs. C57/Bl6/J), partially due to elevated TxA(2) production. Acute inhibition of cyclooxygenases or TxA(2) synthase attenuated the increased TxA(2) production in ApoE and LDLR and improved AA-induced dilation, responses that were mirrored by chronic treatment with low-dose aspirin of 16 wk duration. However, this effect was not temporally stable, and, with longer-duration therapy, the beneficial impact of aspirin on outcomes diminished. A similar, though less robust, pattern to the impact of chronic aspirin therapy on vascular outcomes was identified with chronic antioxidant treatment (TEMPOL). These results suggest that in dyslipidemic mice, the beneficial impact of chronic aspirin therapy on improving vascular outcomes decay with time and that a contributing element to subsequent negative vascular events may be the development of aspirin-resistant TxA(2) production by the vasculature itself.


Assuntos
Aspirina/uso terapêutico , Vasos Sanguíneos/metabolismo , Resistência a Medicamentos , Dislipidemias/genética , Dislipidemias/metabolismo , Tromboxano A2/metabolismo , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aorta/patologia , Apolipoproteínas E/genética , Arteríolas/efeitos dos fármacos , Resistência a Medicamentos/genética , Dislipidemias/complicações , Dislipidemias/patologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores de LDL/genética
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