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1.
Biol Reprod ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38924703

RESUMO

During pregnancy, apoptosis is a physiological event critical in the remodeling and aging of the placenta. Increasing evidence has pointed towards the relevance of hypoxia as modulator of trophoblast cell death. Previous reports have shown that leptin, a placental cytokine, promotes cell survival in both cell culture and placental explant models. The aim of this work is to establish the role of leptin in apoptosis under hypoxic condition in trophoblast cells. In this study, we evaluated the effect of cobalt chloride, a hypoxia mimicking agent that stabilizes the expression of hypoxia inducible factor-1 alpha (HIF-1α), on Swan-71 and human placental explants. Hypoxia chamber was also used to generate 2% oxygen. Apoptosis was determined by the presence of apoptotic nucleus, fragmentation of DNA and Caspase-3 and PARP-1 cleavage. The pro-apoptotic proteins BAX, BID, BAD and BAK and the anti-apoptotic effectors BCL-2, BCL-xL and MCL-1 were also analyzed. We found that HIF-1α stabilization increased the appearance of apoptotic nucleus, fragmentation of DNA, and Caspase-3 and PARP-1 cleavage. Hypoxia mimicking conditions enhanced the expression of pro-apoptotic effectors BAX, BID, BAD and BAK. HIF-1α stabilization also downregulated the level of BCL-2, BCL-xL and MCL-1. All these apoptotic parameters changes were reversed with leptin treatment. Moreover, we showed that leptin action on apoptosis modulation involves PI3K and MAPK signaling pathways. Obtained data demonstrate that HIF-1α stabilization induces apoptosis in human placenta and leptin counteracts this effect, reinforcing its role as a survival cytokine.

2.
Eur J Clin Invest ; : e14214, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613414

RESUMO

The burden of cardiovascular disease is particularly high among individuals with diabetes, even when LDL cholesterol is normal or within the therapeutic target. Despite this, cholesterol accumulates in their arteries, in part, due to persistent atherogenic dyslipidaemia characterized by elevated triglycerides, remnant cholesterol, smaller LDL particles and reduced HDL cholesterol. The causal link between dyslipidaemia and atherosclerosis in T2DM is complex, and our contention is that a deeper understanding of lipoprotein composition and functionality, the vehicle that delivers cholesterol to the artery, will provide insight for improving our understanding of the hidden cardiovascular risk of diabetes. This narrative review covers three levels of complexity in lipoprotein characterization: 1-the information provided by routine clinical biochemistry, 2-advanced nuclear magnetic resonance (NMR)-based lipoprotein profiling and 3-the identification of minor components or physical properties of lipoproteins that can help explain arterial accumulation in individuals with normal LDLc levels, which is typically the case in individuals with T2DM. This document highlights the importance of incorporating these three layers of lipoprotein-related information into population-based studies on ASCVD in T2DM. Such an attempt should inevitably run in parallel with biotechnological solutions that allow large-scale determination of these sets of methodologically diverse parameters.

3.
Int J Mol Sci ; 25(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38397015

RESUMO

Diabetes mellitus (DM) is a highly prevalent disease worldwide, estimated to affect 1 in every 11 adults; among them, 90-95% of cases are type 2 diabetes mellitus. This is partly attributed to the surge in the prevalence of obesity, which has reached epidemic proportions since 2008. In these patients, cardiovascular (CV) risk stands as the primary cause of morbidity and mortality, placing a substantial burden on healthcare systems due to the potential for macrovascular and microvascular complications. In this context, leptin, an adipocyte-derived hormone, plays a fundamental role. This hormone is essential for regulating the cellular metabolism and energy balance, controlling inflammatory responses, and maintaining CV system homeostasis. Thus, leptin resistance not only contributes to weight gain but may also lead to increased cardiac inflammation, greater fibrosis, hypertension, and impairment of the cardiac metabolism. Understanding the relationship between leptin resistance and CV risk in obese individuals with type 2 DM (T2DM) could improve the management and prevention of this complication. Therefore, in this narrative review, we will discuss the evidence linking leptin with the presence, severity, and/or prognosis of obesity and T2DM regarding CV disease, aiming to shed light on the potential implications for better management and preventive strategies.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Leptina , Obesidade , Adulto , Humanos , Doenças Cardiovasculares/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Leptina/metabolismo , Obesidade/metabolismo
4.
Int J Mol Sci ; 25(2)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38256268

RESUMO

Cancer is a complex disease that, despite advances in treatment and the greater understanding of the tumor biology until today, continues to be a prevalent and lethal disease. Chemotherapy, radiotherapy, and surgery are the conventional treatments, which have increased the survival for cancer patients. However, the complexity of this disease together with the persistent problems due to tumor progression and recurrence, drug resistance, or side effects of therapy make it necessary to explore new strategies that address the challenges to obtain a positive response. One important point is that tumor cells can interact with the microenvironment, promoting proliferation, dissemination, and immune evasion. Therefore, immunotherapy has emerged as a novel therapy based on the modulation of the immune system for combating cancer, as reflected in the promising results both in preclinical studies and clinical trials obtained. In order to enhance the immune response, the combination of immunotherapy with nanoparticles has been conducted, improving the access of immune cells to the tumor, antigen presentation, as well as the induction of persistent immune responses. Therefore, nanomedicine holds an enormous potential to enhance the efficacy of cancer immunotherapy. Here, we review the most recent advances in specific molecular and cellular immunotherapy and in nano-immunotherapy against cancer in the light of the latest published preclinical studies and clinical trials.


Assuntos
Imunoterapia , Neoplasias , Humanos , Neoplasias/terapia , Apresentação de Antígeno , Evasão da Resposta Imune , Nanomedicina , Microambiente Tumoral
5.
Int J Mol Sci ; 24(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36982282

RESUMO

Breast cancer (BC) continues to be the most diagnosed tumor in women and a very heterogeneous disease both inter- and intratumoral, mainly given by the variety of molecular profiles with different biological and clinical characteristics. Despite the advancements in early detection and therapeutic strategies, the survival rate is low in patients who develop metastatic disease. Therefore, it is mandatory to explore new approaches to achieve better responses. In this regard, immunotherapy arose as a promising alternative to conventional treatments due to its ability to modulate the immune system, which may play a dual role in this disease since the relationship between the immune system and BC cells depends on several factors: the tumor histology and size, as well as the involvement of lymph nodes, immune cells, and molecules that are part of the tumor microenvironment. Particularly, myeloid-derived suppressor cell (MDSC) expansion is one of the major immunosuppressive mechanisms used by breast tumors since it has been associated with worse clinical stage, metastatic burden, and poor efficacy of immunotherapies. This review focuses on the new immunotherapies in BC in the last five years. Additionally, the role of MDSC as a therapeutic target in breast cancer will be described.


Assuntos
Neoplasias da Mama , Células Supressoras Mieloides , Neoplasias , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias/terapia , Imunoterapia , Microambiente Tumoral
6.
Scand J Clin Lab Invest ; 82(2): 143-149, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35112642

RESUMO

BACKGROUND: Viscoelastic tests (rotational thromboelastometry, ROTEM®), together with the implementation of a specific algorithm for coagulation management in cardiac surgery, enable perioperative coagulopathy to be better controlled. METHODS: Retrospective cohort study including 675 patients who underwent cardiac surgery with cardiopulmonary bypass. The incidence of allogeneic blood transfusions and clinical postoperative complications were analyzed before and after ROTEM® implementation. RESULTS: Following viscoelastic testing and the implementation of a specific algorithm for coagulation management, the incidence of any allogeneic blood transfusion decreased (41.4% vs 31.9%, p = .026) during the perioperative period. In the group monitored with ROTEM®, decreased incidence of transfusion was observed for packed red blood cells (31.3% vs 19.8%, p = .002), fresh frozen plasma (9.8% vs 3.8%, p = .008), prothrombin complex concentrate administration (0.9% vs 0.3%, p = .599) and activated recombinant factor VII (0.3% vs 0.0%, p = .603). Increased incidence was observed for platelet transfusion (4.8% vs 6.8%, p = .530) and fibrinogen concentrate (0.9% vs 3.5%, p = .066), tranexamic acid (0.0% vs 0.6%, p = .370) and protamine administration (0.6% vs 0.9%, p = .908). Similar results were observed in the postoperative period, but with a decreased incidence of platelet transfusion (4.8% vs 3.8%, p = .813). In addition, statistically significant reductions were detected in the incidence of postoperative bleeding (9.5% vs 5.3%, p = .037), surgical reexploration (6.0% vs 2.9%, p = .035), and length of Intensive Care Unit (ICU) stay (6.0 days vs 5.3 days, p = .026). CONCLUSIONS: The monitoring of hemostasis by ROTEM® in cardiac surgery, was associated with decreased incidence of allogeneic blood transfusion, clinical hematologic postoperative complications and lengths of ICU stay.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Tromboelastografia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Humanos , Avaliação de Resultados em Cuidados de Saúde , Hemorragia Pós-Operatória/prevenção & controle , Estudos Retrospectivos , Tromboelastografia/métodos
7.
Int J Mol Sci ; 23(4)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35216099

RESUMO

Leptin is a non-glycosylated 16 kDa protein synthesized mainly in adipose cells. The main function of leptin is to regulate energy homeostasis and weight control in a central manner. There is increasing evidence that leptin also has systemic effects, acting as a link between innate and acquired immune responses. The expression of leptin and its receptor in human dental pulp and periradicular tissues have already been described, as well as several stimulatory effects of leptin protein expression in dental and periodontal tissues. The aim of this paper was to review and to compile the reported scientific literature on the role and effects of leptin in the dental pulp and periapical tissues. Twelve articles accomplished the inclusion criteria, and a comprehensive narrative review was carried out. Review of the available scientific literature concluded that leptin has the following effects on pulpal and periapical physiology: 1) Stimulates odontogenic differentiation of dental pulp stem cells (DPSCs), 2) Increases the expression of dentin sialophosphoprotein (DSPP) and dentin matrix protein-1 (DMP-1), odontoblastic proteins involved in odontoblastic differentiation and dentin mineralization, 3) Stimulates vascular endothelial growth factor (VEGF) expression in human dental pulp tissue and primary cultured cells of human dental pulp (hDPCs), 4) Stimulates angiogenesis in rat dental pulp cells, and 5) Induces the expression of interleucinas 6 and 8 in human periodontal ligament cells (hPDLCs). There is evidence which suggests that leptin is implicated in the dentin mineralization process and in pulpal and periapical inflammatory and reparative responses.


Assuntos
Polpa Dentária/metabolismo , Leptina/metabolismo , Ligamento Periodontal/metabolismo , Animais , Diferenciação Celular/fisiologia , Humanos , Odontogênese/fisiologia
8.
Int J Mol Sci ; 23(9)2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35563589

RESUMO

Obesity is a growing worldwide health problem, affecting many people due to excessive saturated fat consumption, lack of exercise, or a sedentary lifestyle. Leptin is an adipokine secreted by adipose tissue that increases in obesity and has central actions not only at the hypothalamic level but also in other regions and nuclei of the central nervous system (CNS) such as the cerebral cortex and hippocampus. These regions express the long form of leptin receptor LepRb, which is the unique leptin receptor capable of transmitting complete leptin signaling, and are the first regions to be affected by chronic neurocognitive deficits, such as mild cognitive impairment (MCI) and Alzheimer's Disease (AD). In this review, we discuss different leptin resistance mechanisms that could be implicated in increasing the risk of developing AD, as leptin resistance is frequently associated with obesity, which is a chronic low-grade inflammatory state, and obesity is considered a risk factor for AD. Key players of leptin resistance are SOCS3, PTP1B, and TCPTP whose signalling is related to inflammation and could be worsened in AD. However, some data are controversial, and it is necessary to further investigate the underlying mechanisms of the AD-causing pathological processes and how altered leptin signalling affects such processes.


Assuntos
Doença de Alzheimer , Leptina , Doença de Alzheimer/complicações , Humanos , Obesidade/complicações , Receptores para Leptina , Fatores de Risco
9.
Int J Mol Sci ; 24(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36613991

RESUMO

Asthma and obesity are considered as highly prevalent diseases with a great impact on public health. Obesity has been demonstrated to be an aggravating factor in the pathogenesis of asthma. Adipose tissue secretes proinflammatory cytokines and mediators, including leptin, which may promote the development and severity of asthma in obese patients. This study is a systematic review and a meta-analysis based on the relationship between leptin and asthma during obesity. MEDLINE, Cochrane, EMBASE and CINAHL databases were used. Data heterogeneity was analyzed using Cochran's Q and treatment effect with the DerSimonian and Laird method. Random effect analyses were carried out to test data sensitivity. Asymmetry was estimated using Begg's and Egger's tests. All studies showed significant differences in leptin levels. The effect of the measures (p < 0.001), data sensitivity (p < 0.05) and data asymmetry were statistically significant, as well as tBegg's test (p = 0.010) and Egge's test (p < 0.001). Despite the existing limiting factors, the results of this study support the relevant role of leptin in the pathophysiology of asthma in obese subjects. Nevertheless, further studies are needed to obtain better insight in the relationship between leptin and asthma in obesity.


Assuntos
Asma , Leptina , Obesidade , Humanos , Tecido Adiposo/patologia , Asma/complicações , Asma/patologia , Citocinas , Obesidade/complicações , Obesidade/patologia
10.
Int J Mol Sci ; 23(24)2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36555171

RESUMO

Obesity, which is considered a pandemic due to its high prevalence, is a risk factor for many types of cancers, including lymphoma, through a variety of mechanisms by promoting an inflammatory state. Specifically, over the last few decades, obesity has been suggested not only to increase the risk of lymphoma but also to be associated with poor clinical outcomes and worse responses to different treatments for those diseases. Within the extensive range of proinflammatory mediators that adipose tissue releases, leptin has been demonstrated to be a key adipokine due to its pleotropic effects in many physiological systems and diseases. In this sense, different studies have analyzed leptin levels and leptin/leptin receptor expressions as a probable bridge between obesity and lymphomas. Since both obesity and lymphomas are prevalent pathophysiological conditions worldwide and their incidences have increased over the last few years, here we review the possible role of leptin as a promising proinflammatory mediator promoting lymphomas.


Assuntos
Leptina , Linfoma , Humanos , Leptina/metabolismo , Obesidade/complicações , Obesidade/metabolismo , Tecido Adiposo/metabolismo , Adipocinas/metabolismo , Linfoma/metabolismo , Receptores para Leptina/metabolismo
11.
Scand J Clin Lab Invest ; 81(4): 282-289, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33974458

RESUMO

BACKGROUND: Early identification of patients with COVID-19 who may develop critical illness is of great importance. METHODS: In this study a retrospective cohort of 264 COVID-19 cases admitted at Macarena University was used for development and internal validation of a risk score to predict the occurrence of critical illness in hospitalized patients with COVID-19. Backward stepwise logistic regression was used to derive the model, including clinical and laboratory variables predictive of critical illness. Internal validation of the final model used bootstrapped samples and the model scoring derived from the coefficients. External validation was performed in a cohort of 154 cases admitted at Valme and Virgen del Rocio University Hospital. RESULTS: A total of 62 (23.5%) patients developed a critical illness during their hospitalization stay, 21 (8.0%) patients needed invasive ventilation, 34 (12.9%) were admitted at the ICU and the overall mortality was of 14.8% (39 cases). 5 variables were included in the final model: age >59.5 years (OR: 3.11;95%CI 1.39-6.97), abnormal CRP results (OR: 5.76;95%CI 2.32-14.30), abnormal lymphocytes count (OR: 3.252;95%CI 1.56-6.77), abnormal CK results (OR: 3.38;95%CI 1.59-7.20) and abnormal creatinine (OR: 3.30;95%CI 1.42-7.68). The AUC of this model was 0.850 with sensitivity of 65% and specificity of 87% and the IDI and NRI were 0.1744 and 0.2785, respectively. The validation indicated a good discrimination for the external population. CONCLUSIONS: Biomarkers add prognostic information in COVID-19 patients. Our risk-score provides an easy to use tool to identify patients who are likely to develop critical illness during their hospital stay.


Assuntos
Biomarcadores/sangue , COVID-19/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/análise , COVID-19/mortalidade , COVID-19/terapia , Creatina Quinase/sangue , Creatinina/sangue , Estado Terminal , Feminino , Hospitalização , Humanos , Laboratórios , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Respiração Artificial , Estudos Retrospectivos , Medição de Risco , Sensibilidade e Especificidade , Adulto Jovem
12.
Reproduction ; 160(4): 591-602, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32698160

RESUMO

Pregnancy success requires a proper fetal maternal interaction at the establishment of implantation. Leptin has been described as a multitasking cytokine in pregnancy, particularly in the placenta, where it acts as an autocrine hormone. The expression of leptin in normal trophoblastic cells is regulated by different endogenous signals. We have previously reported that 17ß-estradiol upregulates placental leptin expression through genomic and non-genomic mechanisms. To improve the knowledge of estrogen receptor mechanisms in regulating leptin gene expression, we examined transcription nuclear factor kappa B (NFκB) effect on estradiol leptin induction in human BeWo cell line and human term placental explants. We demonstrated that estradiol induction effect on leptin expression is blocked by the inhibition of NFκB signaling. We also found that the overexpression of p65 subunit, the active form of NFκB, induces leptin expression. Moreover, downregulation of estrogen receptor alpha (ERα), through a specific siRNA, abolished NFκB effect on leptin expression. We also demonstrated that ERα enhanced NFκB signaling pathway activation in trophoblastic cells. Estradiol treatment significantly increased p65 expression and phosphorylation of the inhibitory protein κB alpha (IκBα). A reporter plasmid containing NFκB elements was also induced in response to estradiol stimulation. Localization experiments revealed that estradiol treatment induced nuclear localization of overexpressed p65. Moreover, the overexpression of ERα produced a complete displacement of p65 protein to the nucleus. Finally, immunoprecipitation experiments showed the presence of a complex containing ERα and NFκB. All these evidences suggest a cooperative behavior between ERα and NFκB transcription factors to induce leptin transcription.


Assuntos
Coriocarcinoma/patologia , Estrogênios/farmacologia , Leptina/metabolismo , NF-kappa B/metabolismo , Placenta/metabolismo , Neoplasias Uterinas/patologia , Núcleo Celular , Coriocarcinoma/genética , Coriocarcinoma/metabolismo , Feminino , Humanos , Leptina/genética , NF-kappa B/genética , Fosforilação , Placenta/efeitos dos fármacos , Gravidez , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Neoplasias Uterinas/genética , Neoplasias Uterinas/metabolismo
13.
Int J Mol Sci ; 21(16)2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32824322

RESUMO

Inflammation is an essential immune response for the maintenance of tissue homeostasis. In a general sense, acute and chronic inflammation are different types of adaptive response that are called into action when other homeostatic mechanisms are insufficient. Although considerable progress has been made in understanding the cellular and molecular events that are involved in the acute inflammatory response to infection and tissue injury, the causes and mechanisms of systemic chronic inflammation are much less known. The pathogenic capacity of this type of inflammation is puzzling and represents a common link of the multifactorial diseases, such as cardiovascular diseases and type 2 diabetes. In recent years, interest has been raised by the discovery of novel mediators of inflammation, such as microRNAs and adipokines, with different effects on target tissues. In the present review, we discuss the data emerged from research of leptin in obesity as an inflammatory mediator sustaining multifactorial diseases and how this knowledge could be instrumental in the design of leptin-based manipulation strategies to help restoration of abnormal immune responses. On the other direction, chronic inflammation, either from autoimmune or infectious diseases, or impaired microbiota (dysbiosis) may impair the leptin response inducing resistance to the weight control, and therefore it may be a cause of obesity. Thus, we are reviewing the published data regarding the role of leptin in inflammation, and the other way around, the role of inflammation on the development of leptin resistance and obesity.


Assuntos
Doenças Autoimunes/imunologia , Doenças Transmissíveis/imunologia , Leptina/metabolismo , Obesidade/imunologia , Imunidade Adaptativa , Animais , Humanos , Imunidade Inata , Leptina/genética
14.
Cell Tissue Res ; 375(3): 733-742, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30338379

RESUMO

Development of the human placenta is critical for a successful pregnancy. The placenta allows the exchange of oxygen and carbon dioxide and is crucial to manage acid-base balance within a narrow pH. It is known that low pH levels are a risk of apoptosis in several tissues. However, there has been little discussion about the effect of acidic stress in the placenta. Leptin is produced by the placenta with a trophic autocrine effect. Previous results of our group have demonstrated that leptin prevents apoptosis of trophoblast cells under different stress conditions such as serum deprivation and hyperthermia. The purpose of the present work is to evaluate acidic stress consequences in trophoblast explant survival and to determine leptin action in these conditions. For this objective, term human trophoblast explants were cultured at physiological pH (pH 7.4) and at acidic pH (pH 6.8) in the presence or absence of leptin. Western blot assays were performed to study the abundance of active caspase-3 and the p89 fragment of PARP-1. Pro-apoptotic and pro-survival members of Bcl-2 family, as Bax, t-Bid, and Bcl-2, were studied. Moreover, p53 pathway was also evaluated including Mdm-2, the main p53 regulator. Active caspase-3 and cleaved PARP-1 abundances were increased at low extracellular pH. Moreover, t-Bid levels were also augmented as well as p53 expression and phosphorylation on S46. Leptin treatment prevents the consequences of acidosis, decreasing p53 expression and increasing Mdm-2 expression. In summary, this work demonstrated for first time that low pH induces apoptosis of human trophoblast explants involving apoptotic intrinsic pathway, and leptin impairs this effect.


Assuntos
Ácidos/toxicidade , Apoptose/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Leptina/farmacologia , Placenta/citologia , Estresse Fisiológico/efeitos dos fármacos , Adulto , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Feminino , Humanos , Concentração de Íons de Hidrogênio , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Gravidez , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Trofoblastos/citologia , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo
15.
J Cell Mol Med ; 22(2): 716-727, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29160594

RESUMO

Leptin is now considered an important signalling molecule of the reproductive system, as it regulates the production of gonadotrophins, the blastocyst formation and implantation, the normal placentation, as well as the foeto-placental communication. Leptin is a peptide hormone secreted mainly by adipose tissue, and the placenta is the second leptin-producing tissue in humans. Placental leptin is an important cytokine which regulates placental functions in an autocrine or paracrine manner. Leptin seems to play a crucial role during the first stages of pregnancy as it modulates critical processes such as proliferation, protein synthesis, invasion and apoptosis in placental cells. Furthermore, deregulation of leptin levels has been correlated with the pathogenesis of various disorders associated with reproduction and gestation, including polycystic ovary syndrome, recurrent miscarriage, gestational diabetes mellitus, pre-eclampsia and intrauterine growth restriction. Due to the relevant incidence of the mentioned diseases and the importance of leptin, we decided to review the latest information available about leptin action in normal and pathological pregnancies to support the idea of leptin as an important factor and/or predictor of diverse disorders associated with reproduction and pregnancy.


Assuntos
Leptina/metabolismo , Complicações na Gravidez/metabolismo , Tecido Adiposo/metabolismo , Feminino , Humanos , Fatores Imunológicos/metabolismo , Placenta/embriologia , Placenta/metabolismo , Gravidez , Reprodução
16.
Reproduction ; 155(1): R1-R12, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29018059

RESUMO

Leptin is a homeostatic regulator in the placenta where it promotes proliferation, protein synthesis and the expression of tolerogenic maternal response molecules such as HLA-G. Leptin also exerts an anti-apoptotic action in placenta controlling the expression of p53 master cell cycle regulator under different stress conditions. On the other hand, leptin is an integrative target of different placental stimuli. The expression of leptin in placenta is regulated by hCG, insulin, steroids, hypoxia and many other growth hormones, suggesting that it might have an important endocrine function in the trophoblastic cells. The leptin expression is induced involving the cAMP/PKA or cAMP/Epac pathways which have profound actions upon human trophoblast function. The activation of PI3K and MAPK pathways also participates in the leptin expression. Estrogens play a central role during pregnancy, particularly 17ß-estradiol upregulates the leptin expression in placental cells through genomic and non-genomic actions. The leptin promoter analysis reveals specific elements that are active in placental cells. The transcription factors CREB, AP1, Sp1, NFκB and the coactivator CBP are involved in the placental leptin expression. Moreover, placental leptin promoter is a target of epigenetic marks such as DNA methylation and histone acetylation that regulates not only the leptin expression in placenta during pregnancy but also determines the predisposition of acquiring adult metabolism diseases. Taken together, all these results allow a better understanding of leptin function and regulatory mechanisms of leptin expression in human placental trophoblasts, and support the importance of leptin during pregnancy and in programming adult health.


Assuntos
Leptina/metabolismo , Placenta/fisiologia , Animais , Feminino , Humanos , Placenta/citologia , Gravidez , Transdução de Sinais
17.
Clin Lab ; 64(4): 461-465, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29739067

RESUMO

BACKGROUND: The use of a glucose challenge test as the universal screening for gestational diabetes is common in many countries. This test represents significant costs for laboratories and inconveniences for the patients, who have to wait for one hour and, very often, feel discomfort and nausea. In this work we propose the use of fasting glycemia, in a population with low prevalence of gestational diabetes as a pre-screening test that would avoid the oral glucose overload in those pregnant women with low risk of gestational diabetes. METHODS: The study was done with the fasting glucose levels of 6,573 pregnant women who underwent a two steps strategy to screen for gestational diabetes, a first step consisting of a 50 g glucose challenge test, followed when glycemia ≥ 140 mg/dL by a 100 g Oral Glucose Tolerance Test, based on recommendations made by National Diabetes Data Group. RESULTS: The ROC curve for fasting glucose was calculated, and we obtained an AUC = 0.633 (0.569 - 0.696). The sensitivity, specificity, and predictive values were established for different thresholds. CONCLUSIONS: We proposed that women with fasting glycemia ≤ 62 mg/dL, (S = 91.3%, NPV = 98.79% and LR- = 0.87) are in low risk of suffering gestational diabetes, which means that 10% of our population would not undergo the glucose challenge test.


Assuntos
Glicemia/metabolismo , Diabetes Gestacional/sangue , Jejum/sangue , Programas de Rastreamento/métodos , Adulto , Diabetes Gestacional/diagnóstico , Feminino , Teste de Tolerância a Glucose , Humanos , Gravidez , Curva ROC , Estudos Retrospectivos
18.
Gynecol Endocrinol ; 34(2): 175-177, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28942694

RESUMO

Aquaporins are integral membrane proteins that have permeability functions in many tissues. Aquaporin 9 may transport not only water but also small molecules, such as glycerol, monocarboxylates, purines and pyrimidines. Aquaporin 9 is expressed in syncytiotrophoblast of human term placenta, and it may contribute to the embryonic/fetal growth and survival. We have previously found that Aquaporin 9 expression levels seem to be increased in placenta from gestational diabetes. Since leptin plasma levels and leptin expression are increased in placenta from gestational diabetes, we aimed to study the possible role of leptin on Aquaporin 9 expression in human placenta in vitro. The present work shows that leptin produces a dose-dependent increase of Aquaporin 9 expression, resulting in an increase in Aquaporin-9 protein in human trophoblast explants.


Assuntos
Aquaporinas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Leptina/metabolismo , Placenta/metabolismo , Regulação para Cima , Adulto , Aquaporinas/genética , Cesárea , Feminino , Glicosilação , Humanos , Immunoblotting , Concentração Osmolar , Placenta/citologia , Gravidez , Processamento de Proteína Pós-Traducional , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Nascimento a Termo/metabolismo , Técnicas de Cultura de Tecidos , Trofoblastos/citologia , Trofoblastos/metabolismo
19.
Clin Lab ; 63(11): 1939-1944, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29226646

RESUMO

BACKGROUND: The objectives of this study are to compare the effect of sodium fluoride and citrate on the stability of glucose in samples maintained at room temperature up to three hours, and to assess the clinical impact in the O'Sullivan test results after changing the additives in the collecting tubes. METHODS: The selected population was pregnant women between the 24th and 28th week of gestation, who were at the health center to undergo the O'Sullivan test as part of the screening program for GDM (gestacional diabetes mellitus). Two blood samples were extracted from each patient: one using a tube with citrate and sodium fluoride buffer (tubes Vacuette Glucomedics citrate, 2 mL, Ref 454347) (tube C) and another containing just sodium fluoride (BD Vacationer tubes FX fluoride, 2 mL, Ref 368920) (tube F). The statistical treatment of the data was performed using SPSS version 24 and Method validator. Finally, we assessed the real clinical impact of replacing tubes C for tubes F in the classification of pregnant women. To do so, we collected the results of O'Sullivan tests conducted in our hospital during a year, all of them done in tubes F, and we applied the mean difference calculated in T = 1 to estimate the number of pregnant women that should be reclassified. RESULTS: The average glycaemia in tubes C are significantly greater than average glycaemia in tubes F (p < 0.05) at all time points. The clinical impact assessment was done over the 6,526 O'Sullivan test results with a prevalence of positive tests of 21.35%. The prevalence using tubes C instead of tubes F estimated with mean differences previously calculated is 33.45%. CONCLUSIONS: The glucose concentrations in tubes F stored at room temperature up to 3 hours were significantly lower (p < 0.05) than those measured in tubes C stored under the same conditions. We observed that it is in the first minutes after extraction, while the samples are collected and aliquots done, that the glucose consumption occurs in tubes F, but not in tubes C. There is a need to change the preanalytical conditions to prevent any loss of glucose. This will enable more accurate diagnosis and management of diabetes mellitus.


Assuntos
Glicemia/análise , Ácido Cítrico , Fluoreto de Sódio , Diabetes Gestacional/sangue , Diabetes Gestacional/diagnóstico , Feminino , Humanos , Gravidez
20.
Aten Primaria ; 48(5): 325-36, 2016 May.
Artigo em Espanhol | MEDLINE | ID: mdl-26031458

RESUMO

The present paper updates the Clinical Practice Recommendations for the management of cardiovascular risk factors (CVRF) in diabetes mellitus. This is a medical consensus agreed by an independent panel of experts from the Spanish Society of Diabetes (SED). Several consensuses have been proposed by scientific and medical Societies to achieve clinical goals. However, the risk score for general population may lack sensitivity for individual assessment or for particular groups at risk, such as diabetics. Traditional risk factors together with non-traditional factors are reviewed throughout this paper. Intervention strategies for managing CVRF in the diabetic patient are reviewed in detail: balanced food intake, weight reduction, physical exercise, smoking cessation, reduction in HbA1c, therapy for high blood pressure, obesity, lipid disorders, and platelet anti-aggregation. It is hoped that these guidelines can help clinicians in the decisions of their clinical activity. This regular update by the SED Cardiovascular Disease Group of the most relevant concepts, and of greater practical and realistic clinical interest, is presented in order to reduce CVR of diabetics.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Angiopatias Diabéticas/prevenção & controle , Cardiomiopatias Diabéticas/prevenção & controle , Doenças Cardiovasculares/etiologia , Angiopatias Diabéticas/etiologia , Cardiomiopatias Diabéticas/etiologia , Dieta Saudável , Exercício Físico , Humanos , Hiperlipidemias/complicações , Estilo de Vida , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Fatores de Risco , Prevenção do Hábito de Fumar
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