RESUMO
Hypertensive disorders of pregnancy (HDP) represent a substantial risk to maternal and fetal health. Emerging evidence suggests an association between testosterone and pre-eclampsia (PE), potentially mediated through androgen receptors (AR). Nevertheless, the mechanism driving this association is yet to be elucidated. On the other hand, reports of transgender men's pregnancies offer a limited and insightful opportunity to understand the role of high androgen levels in the development of HDP. In this sense, a literature review was performed from a little over 2 decades (1998-2022) to address the association of testosterone levels with the development of HDP. Furthermore, this review addresses the case of transgender men for the first time. The main in vitro outcomes reveal placenta samples with greater AR mRNA expression. Moreover, ex vivo studies show that testosterone-induced vasorelaxation impairment promotes hypertension. Epidemiological data point to greater testosterone levels in blood samples during PE. Studies with transgender men allow us to infer that exogenous testosterone administration can be considered a risk factor for PE and that the administration of testosterone does not affect fetal development. Overall, all studies analyzed suggested that high testosterone levels are associated with PE.
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Given the increasing concern surrounding ultraviolet (UV) radiation-induced skin damage, there has been a rise in demand for UV filters. Currently, UV-filters are considered emerging contaminants. The extensive production and use of UV filters have led to their widespread release into the aquatic environment. Thus, there is growing concern that UV filters may bioaccumulate and exhibit persistent properties within the environment, raising several safety health concerns. Octyl-methoxycinnamate (OMC) is extensively employed as a UV-B filter in the cosmetic industry. While initially designed to mitigate the adverse photobiological effects attributed to UV radiation, the safety of OMC has been questioned with some studies reporting toxic effects on environment. The aim of this review to provide an overview of the scientific information regarding the most widely used organic UV-filter (OMC), and its effects on biodiversity and aquatic environment.
Assuntos
Cosméticos , Protetores Solares , Protetores Solares/toxicidade , Protetores Solares/efeitos da radiação , Cinamatos/toxicidade , Raios Ultravioleta/efeitos adversosRESUMO
Bisphenol A (BPA) is an endocrine-disrupting chemical (EDC) and one of the most produced synthetic compounds worldwide. BPA can be found in epoxy resins and polycarbonate plastics, which are frequently used in food storage and baby bottles. However, BPA can bind mainly to estrogen receptors, interfering with various neurologic functions, its use is a topic of significant concern. Nonetheless, the neurotoxicity of BPA has not been fully understood despite numerous investigations on its disruptive effects. Therefore, this review aims to highlight the most recent studies on the implications of BPA on the neurologic system. Our findings suggest that BPA exposure impairs various structural and molecular brain changes, promoting oxidative stress, changing expression levels of several crucial genes and proteins, destructive effects on neurotransmitters, excitotoxicity and neuroinflammation, damaged blood-brain barrier function, neuronal damage, apoptosis effects, disruption of intracellular Ca2+ homeostasis, increase in reactive oxygen species, promoted apoptosis and intracellular lactate dehydrogenase release, a decrease of axon length, microglial DNA damage, astrogliosis, and significantly reduced myelination. Moreover, BPA exposure increases the risk of developing neurologic diseases, including neurovascular (e.g. stroke) and neurodegenerative (e.g. Alzheimer's and Parkinson's) diseases. Furthermore, epidemiological studies showed that the adverse effects of BPA on neurodevelopment in children contributed to the emergence of serious neurological diseases like attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), depression, emotional problems, anxiety, and cognitive disorders. In summary, BPA exposure compromises human health, promoting the development and progression of neurologic disorders. More research is required to fully understand how BPA-induced neurotoxicity affects human health.
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Transtorno do Espectro Autista , Disruptores Endócrinos , Criança , Humanos , Transtorno do Espectro Autista/induzido quimicamente , Sistema Nervoso , Fenóis/toxicidade , Fenóis/química , Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Disruptores Endócrinos/químicaRESUMO
Bisphenol A (BPA) is one of the most widely used synthetic compound in the manufacture of polycarbonate plastics and epoxy resins. Worryingly, BPA is an endocrine disrupting chemical (EDC) with an estrogenic, androgenic, or anti-androgenic activities. However, the vascular implications of BPA exposome in pregnancy is unclear. In this sense, the present work proposed to understand how BPA exposure impair the vasculature of the pregnant women. To elucidate this, ex vivo studies were performed using human umbilical arteries to explore the acute and chronic effects of BPA. The mode of action of BPA was also explored by analysing the activity (by ex vivo studies) and expression (in vitro studies) analysis of Ca2+ and K+-channels and soluble guanyl cyclase. Moreover, in silico docking simulations were performed to unveil the modes of interactions of BPA with the proteins involved in these signalling pathways. Our study showed that the exposure to BPA may modify the vasorelaxant response of HUA, interfering with NO/sGC/cGMP/PKG pathway by modulation of sGC and activation of BKCa channels. Moreover, our findings suggest that BPA can modulate the HUA reactivity, increasing the L-type Ca2+ Channels (LTCC) activity, a common vascular response observed in hypertensive disorders of pregnancy.
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Disruptores Endócrinos , Artérias Umbilicais , Humanos , Feminino , Gravidez , Fenóis/toxicidade , Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidadeRESUMO
Endocrine disruptor chemicals (EDCs) can have a harmful effect on the human body's endocrine system and thus adversely affect the development, reproduction, neurological, cardiovascular, and immune systems and metabolism in humans and wildlife. According to the World Health Organization, EDCs are mostly man-made and found ubiquitously in our daily lives, notably in pesticides, metals, and additives or contaminants in food and personal care products. Human exposure occurs through ingestion, inhalation, and dermal contact. Bisphenol A (BPA) is a proven EDC capable of mimicking or blocking receptors and altering hormone concentrations and metabolism. Although consumed in low doses, it can stimulate cellular responses and affect the body's functions. In humans, exposure to BPA has been correlated with the onset or development of several diseases. This literature review aimed to verify the effects of BPA on human male infertility using the most recently published literature. Thus, this review allowed us to conclude that this compound seems to have harmful effects on human male fertility, causing changes in hormonal and semen characteristics. However, these conclusions lack more robust and reproducible scientific studies. Even so, and since male infertility prevalence is increasing, preventive measures must be taken to ensure male fertility.
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Disruptores Endócrinos , Infertilidade Masculina , Humanos , Masculino , Reprodução , Fertilidade , Fenóis/efeitos adversos , Compostos Benzidrílicos/toxicidade , Infertilidade Masculina/induzido quimicamente , Infertilidade Masculina/epidemiologia , Disruptores Endócrinos/toxicidadeRESUMO
The Neurovascular Unit (NVU) is formed by vascular and neural cells controlling the cerebral hyperaemia. All the components are anatomically and functionally linked to each other, resulting in a highly efficient regulation of the cerebral blood flow, which, when interrupted, can lead to stroke. An ischemic stroke (IS) is the most common type of stroke with high rates of morbidity, mortality and disability. Therefore, it is of extreme importance to protect the functional and structural integrity of the NVU in patients with IS, understanding the mechanisms involved and how it affects each component of the NVU. Thus, the aim of this work is to analyse how the vascular smooth muscle cells from the rat middle cerebral artery function/react after an ischemic event. To mimic this event, primary cortical cultures were challenged to oxygen and glucose deprivation (OGD) for 4 h and 6 h, and the smooth muscle cells (SMCs) contractility was analysed after exposure to different media previously conditioned by the cortical cultures upon reperfusion. The results show a dual effect on the SMCs response to the vasorelaxant agent, only for cells exposed to the reperfusion media conditioned by neuron-glia cultures challenged by OGD, leading to increased relaxation of the SMCs for OGD 4 h, whereas for OGD 6 h the effect is reversed leading to contraction of the SMCs. These differences demonstrate that the astrocytes mediate the vasoactive response of vascular smooth muscle by releasing factors into the reperfusion medium, and the hypoxia time is fundamental for a beneficial/harmful response by the vascular smooth muscle.
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Isquemia Encefálica , AVC Isquêmico , Traumatismo por Reperfusão , Acidente Vascular Cerebral , Animais , Células Cultivadas , Glucose , Músculo Liso Vascular , Miócitos de Músculo Liso , Oxigênio , RatosRESUMO
Bisphenol A (BPA) is a ubiquitous chemical compound constantly being released into the environment, making it one of the most persistent endocrine-disrupting chemical (EDC) in nature. This EDC has already been associated with developing various pathologies, such as diabetes, obesity, and cardiovascular, renal, and behavioral complications, among others. Therefore, over the years, BPA has been replaced, gradually, by its analog compounds. However, these compounds are structurally similar to BPA, so, in recent years, questions have been raised concerning their safety for human health. Numerous investigations have been performed to determine the effects BPA substitutes may cause, particularly during pregnancy and prenatal life. On the other hand, studies investigating the association of these compounds with the development of cardiovascular diseases (CVD) have been developed. In this sense, this review summarizes the existing literature on the transgenerational transfer of BPA substitutes and the consequent effects on maternal and offspring health following prenatal exposure. In addition, these compounds' effects on the cardiovascular system and the susceptibility to develop CVD will be presented. Therefore, this review aims to highlight the need to investigate further the safety and benefits, or hazards, associated with replacing BPA with its analogs.
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Doenças Cardiovasculares , Sistema Cardiovascular , Disruptores Endócrinos , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Feminino , Humanos , Disruptores Endócrinos/toxicidade , Compostos Benzidrílicos/toxicidade , Doenças Cardiovasculares/induzido quimicamenteRESUMO
Hygiene is essential to avoid diseases, and this is thanks to daily cleaning and disinfection habits. Currently, there are numerous commercial products containing antimicrobial agents, and although they are efficient in disinfecting, it is still not known the effect of the constant use of these products on human health. In fact, a massive use of disinfectants has been observed due to COVID-19, but the possible adverse effects are not yet known. Triclosan is one of the antimicrobial agents used in cosmetic products, toothpaste, and disinfectants. This compound is an endocrine disruptor, which means it can interfere with hormonal function, with its estrogenic and androgenic activity having already been stated. Even if the use of triclosan is well-regulated, with the maximum allowed concentration in the European Union of 0.3% (m/m), its effects on human health are still uncertain. Studies in animals and humans suggest the possibility of harmful health outcomes, particularly for the reproductive system, and in a less extent for the cardiovascular and thyroid functions. Thus, the purpose of this review was to analyse the possible implications of the massive use of triclosan, mainly on the reproductive and cardiovascular systems and on the thyroid function, both in animals and humans.
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Anti-Infecciosos Locais , COVID-19 , Sistema Cardiovascular , Desinfetantes , Disruptores Endócrinos , Triclosan , Animais , Anti-Infecciosos Locais/efeitos adversos , Disruptores Endócrinos/toxicidade , Humanos , Glândula Tireoide , Cremes Dentais , Triclosan/efeitos adversosRESUMO
Phthalate esters are synthetic chemicals used in the plastic industry as plasticizers and consumable products. According to United Nations, about 400 million tons of plastic are produced every year. In parallel with increased production, the concerns about its effects on human health have increased because phthalates are endocrine-disrupting compounds. Humans are continuously exposed to phthalates through different routes of exposure. Experimental data have associated the phthalates exposure to adverse effects on development and reproduction in women (e.g., earlier puberty, primary ovarian insufficiency, endometriosis, preterm birth, or in vitro fertilization) and men (e.g., anogenital distance, cryptorchidism, hypospadias, and changes in adult reproductive function) although there is no consensus. Therefore, one question arises: could the increase in infertility be related to phthalates exposure? To answer this question, we aimed to assess the disrupting-effects of phthalates on the human reproductive system. For this, we reviewed the current literature based on epidemiological and experimental data and experimental studies in humans. The phthalate effects were discussed in a separate mode for female and male reproductive systems. In summary, phthalates induce toxicity in the reproductive system and human development. The increased plastic production may be related to the increase in human infertility.
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Poluentes Ambientais , Ácidos Ftálicos , Nascimento Prematuro , Adulto , Poluentes Ambientais/toxicidade , Feminino , Genitália , Humanos , Recém-Nascido , Masculino , Ácidos Ftálicos/toxicidadeRESUMO
Ultraviolet (UV) filters are chemicals widely used in personal care products (PCPs). Due to their effect as endocrine disruptor compounds (EDCs), the toxicity of UV filters is a current concern for human health. EDC exposure may be correlated to cardiovascular diseases (CVD), but to our knowledge, no studies assessed the UV filters effects as human EDCs at the vascular level. Octylmethoxycinnamate (OMC) is the world's most widely used UV-B filter, present in more than 90% of PCPs. Due to its demonstrated multiple hormonal activities in animal models, this substance is also suspected to be a human EDC. The purpose of this study was to assess the rapid/short-term effects of OMC on arterial tonus and analyse its mode of action (MOA). Using human umbilical arteries, the endocrine effects of OMC were evaluated in in vitro (cellular and organ) experiments by planar cell surface area (PCSA) and organ bath, respectively. Our data show that OMC induces a rapid/short-term smooth muscle relaxation acting through an endothelium-independent MOA, which seems to be shared with oestrogens, involving an activation of soluble guanylyl cyclase (sGC) that increases the cyclic guanosine monophosphate (cGMP) intracellular levels and an inhibition of L-type voltage-operated Ca2+ channels (L-Type VOCC).
Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Cinamatos/farmacologia , Guanilil Ciclase Solúvel/metabolismo , Raios Ultravioleta , Artérias Umbilicais/enzimologia , Artérias Umbilicais/fisiologia , Vasodilatação/efeitos dos fármacos , GMP Cíclico/metabolismo , Ativação Enzimática/efeitos dos fármacos , Humanos , Modelos Biológicos , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Vasoconstrição/efeitos dos fármacosRESUMO
The purpose of this review is to present an update of the main mechanisms involved in the physiological regulation of contraction and relaxation of the human umbilical artery (HUA) smooth muscle cells. A literature review was performed based on the analysis of papers available on PubMed. The most important and relevant studies regarding the regulation of the HUA are presented in this article. The vascular smooth muscle is a highly specialized structure, whose main function is to regulate the vascular tonus. This is controlled by a balance between the cellular signaling pathways that mediate contraction and relaxation. The cells responsible for the contractile property of this muscle are the smooth muscle cells (SMC), and an excellent source of these cells is the HUA, involved in fetoplacental circulation. Since the umbilical blood vessels are not innervated, the HUA tonus is modulated by vasoactive substances that regulate the contractile process. The main vasoactive substances that induce contraction are serotonin, histamine, thromboxane, bradykinin, endothelin 1 and prostaglandin F2α, that are linked to the activation of proteins Gq and Gi/0 . On the other hand, the main vasorelaxation mechanisms are the activation of adenyl and guanil cyclases, potassium channels and the inhibition of calcium channels. The SMC from the HUA allow the study of different cellular mechanisms and their functions. Therefore, these cells are an important tool to study the mechanisms regulating the contractility of this artery, allowing to detect potential therapeutic targets to treat HUA disorders (gestational hypertension and pre-eclampsia).
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Músculo Liso Vascular/fisiologia , Miócitos de Músculo Liso/fisiologia , Artérias Umbilicais/fisiologia , Vasoconstrição/fisiologia , Vasodilatação/fisiologia , Humanos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Artérias Umbilicais/metabolismoRESUMO
Chronic venous disease (CVeD) is a prevalent condition with a significant socioeconomic burden, yet the pathophysiology is only just beginning to be understood. Previous studies concerning the dysregulation of matrix metalloproteinases (MMPs) and their inhibitors (tissue inhibitors of metalloproteinases (TIMPs)) within the varicose vein wall are inconsistent and disregard clinical progression. Moreover, it is highly plausible that MMP and TIMP expression/activity is affected by transforming growth factor (TGF)-ß1 and its signaling receptors (TGFßRs) expression/activity in the vein wall. A case-control study was undertaken to analyze genetic and immunohistochemical differences between healthy (n = 13) and CVeD (early stages: n = 19; advanced stages: n = 12) great saphenous vein samples. Samples were grouped based on anatomic harvest site and subjected to quantitative polymerase chain reaction for MMP1, MMP2, MMP8, MMP9, MMP12, MMP13, TIMP1, TIMP2, TIMP3, TIMP4, TGFßR1, TGFßR2, and TGFßR3 gene expression analysis, and then to immunohistochemistry for immunolocalization of MMP2, TIMP2, and TGFßR2. Decreased gene expression of MMP12, TIMP2, TIMP3, TIMP4, and TGFßR2 was found in varicose veins when compared to controls. Regarding CVeD clinical progression, two facts arose: results across anatomical regions were uneven; decreased gene expression of MMP9 and TGFßR3 and increased gene expression of MMP2 and TIMP3 were found in advanced clinical stages. Most immunohistochemistry results for tunica intima were coherent with qPCR results. In conclusion, decreased expression of TGFßRs might suggest a reduction in TGF-ß1 participation in the MMP/TIMP imbalance throughout CVeD progression. Further studies about molecular events in the varicose vein wall are required and should take into consideration the venous anatomical region and CVeD clinical progression.
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Progressão da Doença , Metaloproteinases da Matriz/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Inibidores Teciduais de Metaloproteinases/genética , Varizes/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Doença Crônica , Estudos Transversais , Feminino , Expressão Gênica , Humanos , Masculino , Metaloproteinases da Matriz/metabolismo , Pessoa de Meia-Idade , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Veia Safena/patologia , Inibidores Teciduais de Metaloproteinases/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Túnica Íntima/patologiaRESUMO
We recently observed in human umbilical artery smooth muscle cells that testosterone activates protein kinase G and stimulates large-conductance Ca²âº activated (BKCa) and voltage sensitive (KV) potassium channels. In the same work, we also show that atrial natriuretic peptide (ANP), an activator of particulate guanylate cyclase (pGC), stimulates the activity of BKCa and KV channels because of protein kinase G activation. The aim of this work was to prove that the relaxant effects of testosterone are also because of the increase of cGMP because of activation of the pGC. Subsarcolemmal cGMP signals were monitored in single cells by recording the cGMP-gated current (ICNG) in human umbilical artery smooth muscle cells expressing the wild-type rat olfactory cyclic nucleotide-gated (CNG) channel. Sodium nitroprusside (10 and 100 µM), ANP (0.1 and 1 µM), or testosterone (0.1, 1, and 10 µM) induced activation of ICNG. This activation induced by testosterone and ANP is bigger than that elicited by sodium nitroprusside. In summary, our study reveals that testosterone and ANP activate the pGC and induce vasorelaxation of human umbilical artery.
Assuntos
Fator Natriurético Atrial/farmacologia , Transdução de Sinais/efeitos dos fármacos , Testosterona/farmacologia , Artérias Umbilicais/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Adulto , Fator Natriurético Atrial/fisiologia , Células Cultivadas , GMP Cíclico/metabolismo , Canais de Cátion Regulados por Nucleotídeos Cíclicos/efeitos dos fármacos , Canais de Cátion Regulados por Nucleotídeos Cíclicos/genética , Feminino , Humanos , Técnicas In Vitro , Nitroprussiato/farmacologia , Técnicas de Patch-Clamp , Gravidez , Testosterona/fisiologia , Vasodilatadores/farmacologiaRESUMO
BACKGROUND: Spironolactone (SPI) is a diuretic widely used to treat cardiovascular diseases (CVD) and is non-specific for mineralocorticoid receptors (MR) and with an affinity for progesterone (PR) and androgen (AR) receptors. Since 2009, it has been suggested that pharmaceuticals are emerging contaminants (called EDC), and recently, it was reported that most EDC are AR and MR antagonists and estrogen receptors (ER) agonists. Concerning SPI, endocrine-disrupting effects were observed in female western mosquitofish, but there are still no data regarding the SPI effects as a possible human EDC. METHODS: In this work, aortic rings were used to analyze the contractility effects of SPI and the mode of action concerning the involvement of Ca2+ channels and endothelial pathways. Moreover, cytotoxic effects were analyzed by MTT assays. RESULTS: SPI induces vasodilation in the rat aorta by endothelium-dependent mechanisms involving NO and by endothelium-independent mechanisms blocking Ca2+ channels. Moreover, a non-monotonic effect characteristic of EDC was observed for SPI-induced decrease in cell viability. CONCLUSIONS: Our findings suggest that SPI may act as an EDC at a human level. However, ex vivo studies with human arteries should be carried out to better understand this drug's implications for human health and future generations.
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Human skin is the first line of photoprotection against UV radiation. However, despite having its defence mechanisms, the photoprotection that the skin exerts is not enough. To protect human skin, the inclusion of UV filters in the cosmetic industry has grown significantly as a photoprotection strategy. Octylmethoxycinnamate, also designated by octinoxate, or 2-ethylhexyl-4-methoxycinnamate (CAS number: 5466-77-3) is one of the most widely used UV-B filter in the cosmetic industry. The toxic effects of OMC have alarmed the public, but there is still no consensus in the scientific community about its use. This article aims to provide an overview of the UV filters' photoprotection, emphasizing the OMC and the possible negative effects it may have on the public health. Moreover, the current legislation will be addressed. In summary, the recommendations should be rethought to assess their risk-benefit, since the existing literature warns us to endocrine-disrupting effects of OMC. Further studies should be focus on the toxicity of OMC alone, in mixture and should consider its degradation products, to improve the knowledge of its risk assessment as EDC.
Assuntos
Cinamatos , Disruptores Endócrinos , Protetores Solares , Raios Ultravioleta , Cinamatos/química , Cinamatos/toxicidade , Humanos , Protetores Solares/toxicidade , Disruptores Endócrinos/toxicidade , Medição de Risco , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Cosméticos/toxicidadeRESUMO
Hypertensive disorders in pregnancy (HDP) are the most prevalent diseases during pregnancy. In addition to the already identified risk factors, exposure to environmental contaminants has been also considered a new one. Phthalates, which are classified as priority environmental pollutants due to their ubiquitousness and endocrine disrupting properties, have been implicated in HDP in some epidemiological studies. Nevertheless, phthalates' vascular impacts still need to be clarified. Thus, we aimed to understand the connection between phthalates exposure and the occurrence of gestational hypertension, as well as the pathway involved in the pathological vascular effects. We investigated diethyl phthalate's (DEP) effect on the vascular reactivity of the human umbilical arteries (HUAs) from normotensive and hypertensive pregnant women. Both DEP's nongenomic (within minutes effect) and genomic (24 h exposure to DEP) actions were evaluated, as well as the contribution of cyclic guanosine monophosphate and Ca2+ channel pathways. The results show that short-term exposure to DEP interferes with serotonin and histamine receptors, while after prolonged exposure, DEP seems to share the same vasorelaxant mechanism as estrogens, through the NO/sGC/cGMP/PKG signaling pathway, and to interfere with the L-type Ca2+ channels. Thus, the vascular effect induced by DEP is similar to that observed in HUA from hypertensive pregnancies, demonstrating that the development of HDP may be a consequence of DEP exposure.
RESUMO
Vascular smooth muscle tone is controlled by a balance between the cellular signaling pathways that mediate the generation of force (vasoconstriction) and release of force (vasodilation). The initiation of force is associated with increases in intracellular calcium concentrations, activation of myosin light-chain kinase, increases in the phosphorylation of the regulatory myosin light chains, and actin-myosin crossbridge cycling. There are, however, several signaling pathways modulating Ca(2+) mobilization and Ca(2+) sensitivity of the contractile machinery that secondarily regulate the contractile response of vascular smooth muscle to receptor agonists. Among these regulatory mechanisms involved in the physiological regulation of vascular tone are the cyclic nucleotides (cAMP and cGMP), which are considered the main messengers that mediate vasodilation under physiological conditions. At least four distinct mechanisms are currently thought to be involved in the vasodilator effect of cyclic nucleotides and their dependent protein kinases: (1) the decrease in cytosolic calcium concentration ([Ca(2+)]c), (2) the hyperpolarization of the smooth muscle cell membrane potential, (3) the reduction in the sensitivity of the contractile machinery by decreasing the [Ca(2+)]c sensitivity of myosin light-chain phosphorylation, and (4) the reduction in the sensitivity of the contractile machinery by uncoupling contraction from myosin light-chain phosphorylation. This review focuses on each of these mechanisms involved in cyclic nucleotide-dependent relaxation of vascular smooth muscle under physiological conditions.
Assuntos
Músculo Liso Vascular/efeitos dos fármacos , Nucleotídeos Cíclicos/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Animais , Cálcio/metabolismo , Cálcio/fisiologia , ATPases Transportadoras de Cálcio/metabolismo , ATPases Transportadoras de Cálcio/fisiologia , Humanos , Camundongos , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Liso Vascular/fisiologia , Quinase de Cadeia Leve de Miosina/antagonistas & inibidores , Quinase de Cadeia Leve de Miosina/metabolismo , Quinase de Cadeia Leve de Miosina/fisiologia , Fosfatase de Miosina-de-Cadeia-Leve/antagonistas & inibidores , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo , Fosfatase de Miosina-de-Cadeia-Leve/fisiologia , Nucleotídeos Cíclicos/metabolismo , Nucleotídeos Cíclicos/fisiologia , Canais de Potássio/agonistas , Canais de Potássio/metabolismo , Canais de Potássio/fisiologia , Ratos , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/metabolismo , Retículo Sarcoplasmático/fisiologia , Trocador de Sódio e Cálcio/metabolismo , Trocador de Sódio e Cálcio/fisiologia , Vasodilatação/fisiologia , Vasodilatadores/metabolismoRESUMO
The aim of the present study was to determine the effects of androgens in the regulation of human umbilical artery (HUA) contractility. The short-term effects of testosterone on the tone of the HUA were investigated, as were the long-term effects of dihydrotestosterone (DHT) on the expression of some proteins involved in the contractile process. Endothelium-denuded HUA were treated for 24 h with DHT (2 µmol/L) or the vehicle control (ethanol) to analyse the genomic effects of androgens. Twenty-four hour treatment of HUA with DHT increased the mRNA expression of the ß(1)-subunit of the large-conductance Ca(2+)-activated (BK(Ca)) channel and decreased expression of the α-subunit of L-type calcium channels. In organ bath studies, testosterone (1-100 µmol/L) produced similar relaxant responses in DHT- and vehicle-treated HUA rings precontracted with 5-HT, histamine and KCl. However, the relaxation response obtained by the combined application of testosterone (100 µmol/L) and nifedipine (10 µmol/L) was significantly greater in DHT- compared with vehicle-treated HUA. The results indicate that the rapid vasorelaxant effects of testosterone that are dependent on both BK(Ca) and voltage-sensitive potassium (K(V)) channel activity in control arteries become dependent solely on K(V) channel activity in DHT-treated HUA. Thus, the present study reveals the importance of the investigation of both the short- and long-term effects of androgens in human arteries.
Assuntos
Androgênios/farmacologia , Di-Hidrotestosterona/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Artérias Umbilicais/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Androgênios/administração & dosagem , Canais de Cálcio Tipo L/biossíntese , Di-Hidrotestosterona/administração & dosagem , Relação Dose-Resposta a Droga , Endotélio Vascular , Feminino , Humanos , Técnicas In Vitro , Subunidades beta do Canal de Potássio Ativado por Cálcio de Condutância Alta/biossíntese , Tono Muscular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Fatores de Tempo , Artérias Umbilicais/metabolismo , Vasoconstritores/farmacologiaRESUMO
Since the beginning of their production, in the 1930s, phthalates have been widely used in the plastics industry to provide durability and elasticity to polymers that would otherwise be rigid, or as solvents in hygiene and cosmetic products. Taking into account their wide range of applications, it is easy to understand why their use has been increasing over the years, making them ubiquitous in the environment. This way, all living organisms are easily exposed to these compounds, which have already been classified as endocrine disruptor compounds (EDC), affecting hormone homeostasis. Along with this increase in phthalate-containing products, the incidence of several metabolic diseases has also been rising, namely diabetes. That said, and considering that factors such as obesity and genetics are not enough to explain this substantial increase, it has been proposed that the exposure to environmental contaminants may also be a risk factor for diabetes. Thus, the aim of this work is to review whether there is an association between the exposure to phthalates and the development of the several forms of diabetes mellitus, during pregnancy, childhood, and adulthood.
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Cardiovascular diseases (CVD) represent the number one cause of death worldwide. The vascular endothelium may play a role in the pathophysiology of CVD diseases. Octylmethoxycinnamate (OMC) is a UV-B filter (CAS number: 5466-77-3) widely used worldwide in numerous personal care products, including sunscreens, daily creams, and makeup. This UV-B filter is considered an endocrine disruptor. Therefore, this investigation aimed to evaluate the direct effects of OMC in human umbilical arteries (HUAs) with endothelium and the possible mechanisms involved in the response. The results demonstrated that OMC exerts a rapid (non-genomic) and endothelium-dependent arterial relaxant effect on HUAs previously contracted with serotonin (5-HT) and Histamine (His). On the other hand, when HUAs were contracted with potassium chloride (KCl), the relaxing effect was only observed in HUAs without endothelium, and it appeared to be inhibited in HUAs with endothelium. Thus, the vasorelaxant effect of OMC depends on the endothelium and depends on the contractile agent used, suggesting that OMC may act through different signaling pathways. Furthermore, computational modulation studies, corroborated the binding of OMC to all the proteins under investigation (eNOS, COX-2, ET-1, and TxA2), with higher affinity for COX-2. In summary, the vascular effect of OMC may involve activating different pathways, i.e., acting through the NO pathway, COX pathway, or activating the endothelin-1 pathway.