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OBJECTIVE: This study aims to explore the significant impact of environmental chemicals on disease development, focusing on their role in developing metabolic and endocrine diseases. The objective is to understand how these chemicals contribute to the increasing prevalence of precocious puberty, considering various factors, including epigenetic changes, lifestyle, and emotional disturbances. METHODS: The study employs a comprehensive review of descriptive observational studies in both human and animal models to identify a degree of causality between exposure to environmental chemicals and disease development, specifically focusing on endocrine disruption. Due to ethical constraints, direct causation studies in human subjects are not feasible; therefore, the research relies on accumulated observational data. RESULTS: Puberty is a crucial life period with marked physiological and psychological changes. The age at which sexual characteristics develop is changing in many regions. The findings indicate a correlation between exposure to endocrine-disrupting chemicals and the early onset of puberty. These chemicals have been shown to interfere with normal hormonal processes, particularly during critical developmental stages such as adolescence. The research also highlights the interaction of these chemical exposures with other factors, including nutritional history, social and lifestyle changes, and emotional stress, which together contribute to the prevalence of precocious puberty. CONCLUSION: Environmental chemicals significantly contribute to the development of certain metabolic and endocrine diseases, particularly in the rising incidence of precocious puberty. Although the evidence is mainly observational, it adequately justifies regulatory actions to reduce exposure risks. Furthermore, these findings highlight the urgent need for more research on the epigenetic effects of these chemicals and their wider impact on human health, especially during vital developmental periods.
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Disruptores Endócrinos , Doenças do Sistema Endócrino , Puberdade Precoce , Adolescente , Animais , Humanos , Disruptores Endócrinos/toxicidade , Sistema Endócrino , Puberdade/fisiologia , Puberdade Precoce/induzido quimicamente , Puberdade Precoce/epidemiologia , Estudos Observacionais como AssuntoRESUMO
Epigenetic changes induced by environmental factors are increasingly relevant in cardiovascular diseases. The most frequent molecular component in cardiac hypertrophy is the reactivation of fetal genes caused by various pathologies, including obesity, arterial hypertension, aortic valve stenosis, and congenital causes. Despite the multiple investigations performed to achieve information about the molecular components of this pathology, its influence on therapeutic strategies is relatively scarce. Recently, new information has been taken about the proteins that modify the expression of fetal genes reactivated in cardiac hypertrophy. These proteins modify the DNA covalently and induce changes in the structure of chromatin. The relationship between histones and DNA has a recognized control in the expression of genes conditioned by the environment and induces epigenetic variations. The epigenetic modifications that regulate pathological cardiac hypertrophy are performed through changes in genomic stability, chromatin architecture, and gene expression. Histone 3 trimethylation at lysine 4, 9, or 27 (H3-K4; -K9; -K27me3) and histone demethylation at lysine 9 and 79 (H3-K9; -K79) are mediators of reprogramming in pathologic hypertrophy. Within the chromatin architecture modifiers, histone demethylases are a group of proteins that have been shown to play an essential role in cardiac cell differentiation and may also be components in the development of cardiac hypertrophy. In the present work, we review the current knowledge about the influence of epigenetic modifications in the expression of genes involved in cardiac hypertrophy and its possible therapeutic approach.
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Women are subject to constitutional changes after menopause, which increases conditions and diseases prone to cardiovascular risks such as obesity and diabetes mellitus. Both estrogens and androgens influence the individual's metabolic mechanism, which controls the fat distribution and the hypothalamic organization of the regulatory centers of hunger and satiety. While androgens tend to accumulate fat in the splanchnic and the visceral region with an increase in cardiovascular risk, estrogens generate more subcutaneous and extremity distribution of adipose tissue. The absence of estrogen during menopause seems to be the main factor that gives rise to the greater predisposition of women to suffer cardiovascular alterations. However, the mechanisms by which estrogens regulate the energy condition of people are not recognized. Estrogens have several mechanisms of action, which mainly include the modification of specific receptors that belong to the steroid receptor superfamily. The alpha estrogen receptors (ERα) and the beta receptors (ERß) have a fundamental role in the metabolic control of the individual, with a very characteristic corporal distribution that exerts an influence on the metabolism of lipids and glucose. Despite the significant amount of knowledge in this field, many of the regulatory mechanisms exerted by estrogens and ER continue to be clarified. This review will discuss the role of estrogens and their receptors on the central regulation of caloric expenditure and the influence they exert on the differentiation and function of adipocytes. Furthermore, chemical substances with a hormonal activity that cause endocrine disruption with affectation on estrogen receptors will be considered. Finally, the different medical therapies for the vasomotor manifestations of menopause and their role in reducing obesity, diabetes, and cardiovascular risk will be analyzed.
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Disruptores Endócrinos , Estrogênios , Adipócitos/metabolismo , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio , Estrogênios/metabolismo , Feminino , Glucose , Humanos , Lipídeos , Obesidade , Receptores de Estrogênio/metabolismoRESUMO
Thyroid hormones have a fundamental impact on cardiac function that is mediated by genomic and nongenomic effects, alterations that condition physiological repercussions that lead to changes in frequency, contractility, rhythm and cardiac output as well as an increase in the incidence and prevalence of different cardiovascular diseases. This document presents an updated review of the implications that hyperthyroidism has in different cardiac conditions, including its importance in the evaluation of perioperative cardiovascular risk.
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The obesity and the associated non-communicable diseases (NCDs) are globally increasing in their prevalence. While the modern-day lifestyle required less ventilation of metabolic energy through muscular activities, this lifestyle transition also provided the unlimited accession to foods around the clock, which prolong the daily eating period of foods that contained high calorie and high glycemic load. These situations promote the high continuous flux of carbon substrate availability in mitochondria and induce the indecisive bioenergetic switches. The disrupted bioenergetic milieu increases the uncoupling respiration due to the excess flow of the substrate-derived reducing equivalents and reduces ubiquinones into the respiratory chain. The diversion of the uncoupling proton gradient through adipocyte thermogenesis will then alleviate the damaging effects of free radicals to mitochondria and other organelles. The adaptive induction of white adipose tissues (WAT) to beige adipose tissues (beAT) has shown beneficial effects on glucose oxidation, ROS protection and mitochondrial function preservation through the uncoupling protein 1 (UCP1)-independent thermogenesis of beAT. However, the maladaptive stage can eventually initiate with the persistent unhealthy lifestyles. Under this metabolic gridlock, the low oxygen and pro-inflammatory environments promote the adipose breakdown with sequential metabolic dysregulation, including insulin resistance, systemic inflammation and clinical NCDs progression. It is unlikely that a single intervention can reverse all these complex interactions. A comprehensive protocol that includes dietary, nutritional and all modifiable lifestyle interventions, can be the preferable choice to decelerate, stop, or reverse the NCDs pathophysiologic processes.
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Tecido Adiposo Branco , Obesidade , Tecido Adiposo , Humanos , Estilo de Vida , Obesidade/prevenção & controle , Proteína Desacopladora 1RESUMO
Resumen La obesidad es una enfermedad crónica, no transmisible, que recientemente ha tenido una connotación especial debido al aumento de su prevalencia en países en vía de desarrollo. Este incremento está relacionado con un aumento en la aparición de enfermedades metabólicas y el riesgo cardiovascular. Si bien la prevalencia de obesidad está aumentando en todos los países del mundo, existen diferencias regionales tanto en la prevalencia como en las tendencias de la obesidad. Por consiguiente, comprender los impulsores de estas diferencias regionales podría ayudar a proporcionar orientación para las estrategias de intervención más prometedoras. A pesar de considerarse una eventualidad simple en una proporción de lo que se ingiere y lo que se gasta, existen muchos factores que regulan esta enfermedad. No es sencillo encontrar medidas terapéuticas para la obesidad, pues sus causas son múltiples. En forma reciente, ha despertado un especial interés la caracterización funcional de los adipocitos, específicamente de los adipocitos beige, dado que su función está íntimamente relacionada con las circunstancias externas del ambiente y tienen una flexibilidad que les permite producir energía y mejorar muchos de los parámetros metabólicos en los individuos. En este manuscrito se hará énfasis en las características de las células adiposas y su influencia en el riesgo cardiovascular.
Abstract Obesity is a chronic non-transmissible disease that has recently had a special connotation due to the increase of its prevalence in developing countries. The increase in obesity is related to an expansion in the appearance of metabolic diseases and cardiovascular risk. Although the prevalence of obesity is increasing in all countries of the world, there are regional differences in both the prevalence and trends of obesity. Therefore, understanding the circumstances of these regional differences could help provide guidance for the most promising intervention strategies. Despite being considered a simple outcome in a proportion of what is ingested and what is spent, there are many factors that regulate this disease. It is not easy to find therapeutic measures for obesity, because their causes are multiple. Recently, the functional characterization of adipocytes, especially Beige adipocytes, has been of particular interest since their function is intimately related to the external circumstances of the environment and they have a flexibility that allows them to produce energy and improve many of the metabolic parameters in individuals. In the present manuscript we will focus on the characteristics of fat cells and their influence on cardiovascular risk.
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Obesidade , Adipócitos Marrons , Adipócitos Brancos , Adipócitos Bege , Fatores de Risco de Doenças CardíacasRESUMO
Adipose tissue is the largest endocrine organ in humans and has an important influence on many physiological processes throughout life. An increasing number of studies have described the different phenotypic characteristics of fat cells in adults. Perhaps one of the most important properties of fat cells is their ability to adapt to different environmental and nutritional conditions. Hypothalamic neural circuits receive peripheral signals from temperature, physical activity or nutrients and stimulate the metabolism of white fat cells. During this process, changes in lipid inclusion occur, and the number of mitochondria increases, giving these cells functional properties similar to those of brown fat cells. Recently, beige fat cells have been studied for their potential role in the regulation of obesity and insulin resistance. In this context, it is important to understand the embryonic origin of beige adipocytes, the response of adipocyte to environmental changes or modifications within the body and their ability to transdifferentiate to elucidate the roles of these cells for their potential use in therapeutic strategies for obesity and metabolic diseases. In this review, we discuss the origins of the different fat cells and the possible therapeutic properties of beige fat cells.
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Diabetes mellitus (DM) is one of the main causes of morbidity and mortality, with an increasing incidence worldwide. The impact of DM on public health in developing countries has triggered alarm due to the exaggerated costs of the treatment and monitoring of patients with this disease. Considerable efforts have been made to try to prevent the onset and reduce the complications of DM. However, because insulin-producing pancreatic ß-cells progressively deteriorate, many people must receive insulin through subcutaneous injection. Additionally, current therapies do not have consistent results regarding the prevention of chronic complications. Leveraging the approval of real-time continuous glucose monitors and sophisticated algorithms that partially automate insulin infusion pumps has improved glycemic control, decreasing the burden of diabetes management. However, these advances are facing physiologic barriers. New findings in molecular and cellular biology have produced an extraordinary advancement in tissue development for the treatment of DM. Obtaining pancreatic ß-cells from somatic cells is a great resource that currently exists for patients with DM. Although this therapeutic option has great prospects for patients, some challenges remain for this therapeutic plan to be used clinically. The purpose of this review is to describe the new techniques in cell biology and regenerative medicine as possible treatments for DM. In particular, this review highlights the origin of induced pluripotent cells (iPSCs) and how they have begun to emerge as a regenerative treatment that may mitigate the pathology of this disease.
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Algoritmos , Diabetes Mellitus/terapia , Células-Tronco Pluripotentes Induzidas/transplante , Transplante de Células-Tronco , Doença Crônica , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologiaRESUMO
BACKGROUND: Diabetes mellitus with autosomal dominant inheritance, such as maturity-onset diabetes of the young (MODY), is a genetic form of diabetes mellitus. MODY is a type of monogenic diabetes mellitus in which multiple genetic variants may cause an alteration to the functioning of beta cells. The three most known forms of MODY are caused by modifications to the hnf4a, gck, and hnf1a genes. However, other MODY variants can cause multiple alterations in the embryonic development of the endoderm. This is the case in patients presenting with MODY5, who have a mutation of the hepatic nuclear factor 1B (hnf1b) gene. CASE PRESENTATION: We present the clinical case of a 15 year-old patient with a family history of diabetes mellitus and a classical MODY type 5 (MODY5) phenotype involving the pancreas and kidney, with a novel, unreported mutation in the hnf1b gene. CONCLUSIONS: MODY5 is characterised by a mutation in the hnf1b gene, which plays an important role in the development and function of multiple organs. It should be suspected in patients with unusual diabetes and multisystem involvement unrelated to diabetes.
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Resumen Introducción: El valor nutritivo de las proteínas derivadas de la carne magra de cerdo ha cambiado ostensiblemente con la tecnificación en la producción y la posibilidad de obtener productos que conserven un alto valor nutritivo. No obstante, en nuestro medio su consumo se ha estigmatizado por un posible aumento de riesgo cardiovascular. Objetivo: Evaluar el impacto del consumo de la carne magra de cerdo sobre algunos parámetros antropométricos y bioquímicos de riesgo cardiovascular. Métodos: Se realizó un estudio de seguimiento a un grupo de 47 personas sanas que consumieron 200 gramos de carne magra de cerdo durante un periodo de ocho semanas, durante las cuales se valoraron parámetros bioquímicos, antropométricos, nutricionales y de riesgo cardiovascular. Resultados: Se observó que, tanto a las cuatro como a las ocho semanas, los niveles de colesterol LDL y triglicéridos no variaron. No obstante, los niveles de colesterol HDL y los micronutrientes zinc, hierro y vitamina B12 aumentaron en plasma luego de ocho semanas de consumo de carne magra de cerdo. De igual forma, marcadores metabólicos, como la adiponectina y el IGF-1, incrementaron luego de ocho semanas de consumo. Conclusiones: De acuerdo con estas observaciones la carne magra de cerdo puede mejorar el aporte de algunos micronutrientes y parámetros metabólicos sin que se haya evidenciado un efecto adverso sobre ciertos parámetros de riesgo cardiovascular en individuos sanos.
Abstract Introduction: The nutritional value of proteins derived from lean pork meat has essentially changed with the introduction of technology in the production and the possibility of obtaining products that retain a high nutritional value. However, its consumption has been stigmatised in this country due to a possible increase in cardiovascular risk. Objective: To evaluate the impact of consuming lean pork meat on some anthropometric and biochemical parameters of cardiovascular risk. Methods: A follow-up study was conducted on a population of 47 healthy subjects that consumed 200 grammes of lean pork meat for a period of 8 weeks. An evaluation was made of some biochemical, anthropometric, nutritional and cardiovascular risk parameters. Results: No changes were observed in the LDL-cholesterol or triglyceride levels. However, the plasma levels of HDL-cholesterol, as well as those of micronutrients such as zinc, iron and vitamin B12, increased after 8 weeks of consuming lean pork meat. Furthermore, metabolic markers, like adiponectin and IGF-1, also increased after eight weeks of consumption. Conclusions: According to these observations, lean pork meat may improve the supply of some micronutrients, as well as some metabolic parameters, with no evidence of any adverse effects on certain cardiovascular risk factors in healthy individuals.
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Humanos , Masculino , Feminino , Adulto , Fenômenos Bioquímicos , Antropometria , Carne de Porco , Fatores de Risco de Doenças Cardíacas , Fenômenos Fisiológicos da Nutrição , Vitamina B 12 , HDL-Colesterol , LDL-ColesterolRESUMO
Resumen La pandemia por COVID-19 ha desencadenado un impacto tremendo en la humanidad debido a las implicaciones culturales, económicas y sociales que este tipo de infecciones ha ocasionado. Quizá preguntas iniciales, mirando en retrospectiva corta, acerca de los hechos que comenzaron esta infección, darían una luz para prevenir eventos de esta índole en el futuro. ¿Cuáles fueron las circunstancias que desencadenaron la pandemia?, ¿fue una serie de transmisiones zoonóticas que produjeron la infección en los humanos?, ¿ha tenido algo que ver el ambiente? El desafío de las grandes potencias para mantener la hegemonía, dará curso a una plétora de investigaciones acerca de la biología del virus, las variables epidemiológicas y las enfermedades crónicas de riesgo cardiovascular. En este manuscrito se analizan algunos de estos cuestionamientos.
Abstract The COVID-19 pandemic has had a tremendous impact on humanity due to the cultural, financial, and social implications caused by this type of infection. Perhaps some initial questions, looking at the short-term retrospective, about the facts that started this infection, could shed some light on preventing events of this kind in the future. What were the circumstances that triggered the pandemic? Was it a series of zoonotic transmissions that produced the infection in humans? Is it something to do with the environment? The challenge of the major powers to maintain dominance, will give rise to a plethora of studies on the biology of the virus, the epidemiological variables, and the chronic diseases of cardiovascular risk. Some of these questions are analysed in this article.
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Fatores Epidemiológicos , COVID-19 , Meio Ambiente , Fatores de Risco de Doenças CardíacasRESUMO
The imbalance between food intake and energy expenditure causes high accumulation of triglycerides in adipocytes. Obesity is related with the increased lipid accumulation in white adipose tissue, which is a major risk factor for the development of metabolic disorders, such as type 2 diabetes and cardiovascular disease. This study highlights the role of E1A-like inhibitor of differentiation 1 (EID1) in the modulation of adipogenesis through the downregulation of glycerol-3-phosphate dehydrogenase (GPDH), which is a key enzyme in the synthesis of triglycerides and is considered to be a marker of adipogenesis. By analyzing DNA microarray data, we found that when EID1 is overexpressed in preadipocytes (3T3-L1 cells) during adipocyte differentiation, EID1 inhibits lipid accumulation through the downregulation of GPDH. In contrast, EID1 is not involved in the regulation of intracellular glucose via the translocation of glucose transporter. A confocal image analysis showed that EID1 is located in the nucleus of preadipocytes in the form of speckles, which could be involved as a regulator of the transcriptional process. We further confirmed that EID1 is able to bind to the promoter sequence of GPDH in the nucleus. These findings provide a molecular explanation for the inhibitory effect of EID1 on lipid accumulation in adipocytes.
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Glicerolfosfato Desidrogenase/metabolismo , Metabolismo dos Lipídeos/fisiologia , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Células 3T3-L1 , Adipócitos/metabolismo , Adipogenia/fisiologia , Tecido Adiposo Branco/metabolismo , Animais , Diferenciação Celular/fisiologia , Linhagem Celular , Núcleo Celular/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Regulação para Baixo/fisiologia , Glucose/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Camundongos , Obesidade/metabolismo , Regiões Promotoras Genéticas/genética , Triglicerídeos/metabolismoRESUMO
Actualmente el mundo atraviesa una de las peores crisis a nivel salud secundario a la infección por un nuevo coronavirus de alta transmisibilidad y mortalidad, que ha impactado múltiples aspectos. Se ha establecido de forma general que la severidad de la infección está asociada con edad avanzada y comorbilidades como hipertensión y diabetes. Por otro lado, la obesidad en este momento representa una de las mayores amenazas del sector salud, por su gran relación con morbimortalidad a nivel cardiometabólico, esto conlleva a un alto costo de la enfermedad. Este artículo busca alertar sobre lo que han llamado algunos expertos el "choque de dos pandemias", esto dado al aumento de la prevalencia de obesidad a nivel mundial, donde nuestro país no está exento, que podría relacionarse con un número mayor de personas vulnerables a la infección por COVID-19 y sus complicaciones respiratorias y de esta manera evitar desenlaces catastróficos.
Currently the world is going through one of the worst health crises secondary to the infection by a new highly transmissible and deadly coronavirus, which has impacted multiple aspects. It has been generally established that the severity of the infection is associated with old age and comorbidities such as hypertension and diabetes. On the other hand, obesity at this time represents one of the greatest threats to the health sector, due to its strong relationship with morbidity and mortality at the cardiometabolic level which leads to a high cost of the disease. This article seeks to warn about what some experts have called the "clash of two pandemics", this given the increasing prevalence of obesity worldwide, where our country is not exempt, which could be related with a greater number of people vulnerable to COVID-19 infection and related respiratory complications and thus avoid catastrophic outcomes.
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Infecções por Coronavirus/complicações , Obesidade , InflamaçãoRESUMO
Adipose tissue is traditionally categorized into white and brown relating to their function and morphology. The classical white adipose tissue builds up energy in the form of triglycerides and is useful for preventing fatigue during periods of low caloric intake and the brown adipose tissue more energetically active, with a greater number of mitochondria and energy production in the form of heat. Since adult humans possess significant amounts of active brown fat depots and its mass inversely correlates with adiposity, brown fat might play an important role in human obesity and energy homeostasis. New evidence suggests two types of thermogenic adipocytes with distinct developmental and anatomical features: classical brown adipocytes and beige adipocytes. Beige adipocyte has recently attracted special interest because of its ability to dissipate energy and the possible ability to differentiate themselves from white adipocytes. The presence of brown and beige adipocyte in human adults has acquired attention as a possible therapeutic intervention for metabolic diseases. Importantly, adult human brown appears to be mainly composed of beige-like adipocytes, making this cell type an attractive therapeutic target for obesity and obesity-related diseases, such as atherosclerosis, arterial hypertension and diabetes mellitus type 2. Because many epigenetics changes can affect beige adipocyte differentiation from adipose progenitor cells, the knowledge of the circumstances that affect the development of beige adipocyte cells may be important to new pathways in the treatment of metabolic diseases. New molecules have emerged as possible therapeutic targets, which through the impulse to develop beige adipocytes can be useful for clinical studies. In this review will discuss some recent observations arising from the unique physiological capacity of these cells and their possible role as ways to treat obesity and diabetes mellitus type 2.
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Adipócitos Bege/metabolismo , Doenças Metabólicas/metabolismo , Adipócitos Bege/efeitos dos fármacos , Adipócitos Bege/fisiologia , Animais , Fármacos Antiobesidade/farmacologia , Fármacos Antiobesidade/uso terapêutico , Exercício Físico , Humanos , Doenças Metabólicas/tratamento farmacológico , TermogêneseRESUMO
Members of the jumonji-containing lysine demethylase protein family have been associated with cancer development, although their specific roles in the evolution of tumor cells remain unknown. This work examines the effects of lysine demethylase 4C (KDM4C) knockdown on the behavior of a triple-negative breast cancer cell line. KDM4C expression was knocked-down by siRNA and analyzed by Western blot and immunofluorescence. HCC38 cell proliferation was examined by MTT assay, while breast cancer cells' migration and invasion were tested in Transwell format by chemotaxis. Immunofluorescence assays showed that KDM4C, which is a key protein for modulating histone demethylation and chromosome stability through the distribution of genetic information, is located at the chromosomes during mitosis. Proliferation assays demonstrated that KDM4C is important for cell survival, while Transwell migration and invasion assays indicated that this protein is relevant for cancer progression. These data indicate that KDM4C is relevant for breast cancer progression and highlight its importance as a potential therapeutic target.
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The anatomical location of adipose tissue might have direct implications for its functionality and risk of cardiovascular disease. Adipose tissue surrounding blood vessels may be thermogenically more active in specific areas of the body, releasing substances that regulate vascular metabolism. In humans, the phenotypic characteristics of adipose tissue surrounding the aorta and the cardiovascular disease risk that it might entail remain largely unknown. Here, we compared thermogenesis-related molecular features of human periaortic adipose tissue samples with those of subcutaneous adipose tissue, obtained by sternotomy from 42 patients undergoing cardiovascular surgery. To determine the expression of genes related to energy expenditure and the levels of some adipokines, histological examinations, quantitative PCR, and protein expression measurements in adipocyte precursor cells were performed. Periaortic adipocytes were smaller than those from subcutaneous tissue. Moreover, weight gain induced periaortic adipocyte hypertrophy (r = -0.91, p<0.01). Compared to subcutaneous tissue, adiponectin, FABP4, IL-4 and IL-6 was decreased in periaortic adipocytes, whereas FGF21, UCP-1, PGC-1a, CITED1, Omentin and TFAM (Mitochondrial protein) increased. Upon analyzing patients' clinical conditions, it emerged that the levels of PGC-1a both in male (r = -0.48 p<0.04) and female (r = -0.61, p<0.05) and TFAM in male (r = -0.72, p<0.0008) and female (r = -0.86, p<0.002) decreased significantly with progressive weight gain. However, no differences were observed in patients with diabetes mellitus 2 or Hyperlipidemia. Adipocytes surrounding the ascending aorta present markers of major thermogenic activity than those in subcutaneous tissue. Nevertheless, this characteristic might change, due to unfavorable metabolic conditions such as obesity, which is a risk factor for cardiovascular disease.
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Tecido Adiposo/metabolismo , Aorta , Peso Corporal , Termogênese , Adipócitos/metabolismo , Adipocinas/genética , Adipocinas/metabolismo , Idoso , Índice de Massa Corporal , Células Cultivadas , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , Termogênese/genéticaRESUMO
The development of cardiovascular pathologies is partly attributed to epigenetic causes, including histone methylation, which appears to be an important marker in hearts that develop cardiac hypertrophy. Previous studies showed that the histone demethylase JMJD2A can regulate the hypertrophic process in murine cardiomyocytes. However, the influence of JMJD2A on cardiac hypertrophy in a human cardiomyocyte model is still poorly understood. In the present study, cardiomyocytes derived from human induced pluripotent stem cells (iPSCs) were used. Hypertrophy was induced by angiotensin II and endothelin-1 (ET-1), and transfections were performed to overexpress JMJD2A and for small interfering RNA (siRNA)-induced silencing of JMJD2A. Gene expression analyses were determined using RT-PCR and Western blot. The expression levels of B-type natriuretic peptide (BNP), natriuretic peptide A (ANP), and beta myosin heavy chain (ß-MHC) were increased by nearly 2-10-fold with ET-1 compared with the control. However, a higher level of JMJD2A and UTX was detected, whereas the level of JMJD2C was lower. When cardiomyocytes were transiently transfected with JMJD2A, an increase close to 150% in BNP was observed, and this increase was greater after treatment with ET-1. To verify the specificity of JMJD2A activity, a knockdown was performed by means of siRNA-JMJD2A, which led to a significant reduction in BNP. The involvement of JMJD2A suggests that histone-specific modifications are associated with genes encoding proteins that are actively transcribed during the hypertrophy process. Since BNP is closely related to JMJD2A expression, we suggest that there could be a direct influence of JMJD2A on the expression of BNP. These results may be studied further to reduce cardiac hypertrophy via the regulation of epigenetic modifiers.
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Adipose tissue can affect the metabolic control of the cardiovascular system, and its anatomic location can affect the vascular function differently. In this study, biochemical and phenotypical characteristics of adipose tissue from periaortic fat were evaluated. Periaortic and subcutaneous adipose tissues were obtained from areas surrounding the ascending aorta and sternotomy incision, respectively. Adipose tissues were collected from patients undergoing myocardial revascularization or mitral valve replacement surgery. Morphological studies with hematoxylin/eosin and immunohistochemical assay were performed in situ to quantify adipokine expression. To analyze adipogenic capacity, adipokine expression, and the levels of thermogenic proteins, adipocyte precursor cells were isolated from periaortic and subcutaneous adipose tissues and induced to differentiation. The precursors of adipocytes from the periaortic tissue accumulated less triglycerides than those from the subcutaneous tissue after differentiation and were smaller than those from subcutaneous adipose tissue. The levels of proteins involved in thermogenesis and energy expenditure increased significantly in periaortic adipose tissue. Additionally, the expression levels of adipokines that affect carbohydrate metabolism, such as FGF21, increased significantly in mature adipocytes induced from periaortic adipose tissue. These results demonstrate that precursors of periaortic adipose tissue in humans may affect cardiovascular events and might serve as a target for preventing vascular diseases.
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Type two innate immune system is anti-inflammatory and may play an important role as the means whereby "browning" is induced in subcutaneous adipocytes. It was shown that IL-4 may influence the fate of adipose cell precursors by promoting differentiation towards more thermogenic adipocytes in mice. Here, we investigated the influence of IL-4 and IL-4 receptor, a type two immune cytokine pathway, on the metabolic activity and thermogenic potential of human adipocytes differentiated from adipose-derived mesenchymal stem cells (ADMSCs) obtained from subcutaneous samples of healthy women undergoing abdominoplasty. Western blot analysis, qPCR, and biochemical analyses were performed 10 days after ADMSC differentiation into mature adipocytes was induced. IL-4 receptor was expressed in both precursor and differentiated adipocytes, and IL-4 treatment increased phosphorylation Y641 of signal transducer and activator of transcription 6 (STAT6) in both cell types. IL-4 treatment also increased expression of thermogenic proteins PGC-1α, UCP-1, and CITED1. In addition, IL-4 increased the secretion of adiponectin, leptin, and FGF21 and promoted lipolysis in differentiated adipocytes. In conclusion, IL-4 may directly modulate differentiation of human adipocytes towards a beige phenotype acting through IL-4 receptors on both adipose precursors and differentiated human adipocytes, metabolic effect that must be considered in some antiallergic drugs.