The hypothyroid brain

  The thyroid gland is controlled by a feedback system, the hypothalamus-pituitary-thyroid axis, and produces thyroid hormone (TH), which plays a critical role in growth, development and cellular metabolism. Diseases of the thyroid are well defined clinically and biochemically and diseases affecting thyroid function can cause both clinical hypothyroidisms, the most common cause of thyroid dysfunction, occurs when there is a decrease in the production of thyroid hormones, and hyperthyroidism, when there is an increase in hormone production. Common systemic manifestations of hypothyroidism include fatigue, dry skin, weight gain, hair loss, cold intolerance, hoarseness and constipation. Patients affected by this condition present a number of central and peripheral signs in the nervous system that may be neurological manifestations that occur along with the systemic disease. The conversion of thyroid hormone in the target tissue is done by three distinct deiodinases: type I, type II and type III. Each deiodinase has a different function in order to maintain thyroid hormone homeostasis in the tissues. Other proteins important for thyroid state are the TH transporters. MCT8, OATP1C1 and LAT1 and 2 transporters regulate T4 and T3 flow in the cells. The action of THs depends on the interaction of several proteins that are specialized in the control of thyroid hormone homeostasis not only in the brain but also in various tissues. THs are important for the maturation of the brain from the intrauterine period and remain important to adulthood. When there is some disturbance in the control mechanisms for the state of thyroid hormone, the consequences to the tissues, especially the CNS, can range from mild damage to severe impairment in neuronal development

Dipeptidyl peptidase IV inhibition upregulates GLUT4 translocation and expression in heart and skeletal muscle of spontaneously hypertensive rats

The purpose of the current study was to test the hypothesis that the dipeptidyl peptidase IV (DPPIV) inhibitor sitagliptin, which exerts anti-hyperglycemic and anti-hypertensive effects, upregulates GLUT4 translocation, protein levels, and/or mRNA expression in heart and skeletal muscle of spontaneously hypertensive rats (SHRs). Ten days of treatment with sitagliptin (40 mg/kg twice daily) decreased plasma DPPIV activity in both young (Y, 5-week-old) and adult (A, 20-week-old) SHRs to similar extents ( similar to 85%). However, DPPIV inhibition only lowered blood pressure in Y-SHRs (119 +/- 3 vs. 136 +/- 4 mmHg). GLUT4 translocation, total protein levels and mRNA expression were decreased in the heart, soleus and gastrocnemius muscle of SHRs compared to age-matched Wistar Kyoto (WKY) normotensive rats. These differences were much more pronounced between A-SHRs and A-WKY rats than between Y-SHRs and Y-WKY rats. in Y-SHRs, sitagliptin normalized GLUT4 expression in the heart, soleus and gastrocnemius. in A-SHRs, sitagliptin increased GLUT4 expression to levels that were even higher than those of A-WKY rats. Sitagliptin enhanced the circulating levels of the DPPIV substrate glucagon-like peptide-1 (GLP-1) in SHRs. in addition, stimulation of the GLP-1 receptor in cardiomyocytes isolated from SHRs increased the protein level of GLUT4 by 154 +/- 13%. Collectively, these results indicate that DPPIV inhibition upregulates GLUT4 in heart and skeletal muscle of SHRs. the underlying mechanism of sitagliptin-induced upregulation of GLUT4 in SHRs may be, at least partially, attributed to GLP-1. (C) 2012 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fac Med ABC, Dept Morphol & Physiol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Med, São Paulo, BrazilUniv São Paulo Med Sch, Inst Heart, Lab Genet & Mol Cardiol, BR-05403900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Med, São Paulo, BrazilFAPESP: 2007/52945-8CNPq: 480775/2007-9Web of Scienc

Estudo Expressão Gênica Das Semaforinas E De Seus Receptores No Cérebro De Ratos Com Hipotireoidismo Subclínico

The Action Of Thyroid Hormones (Hts) Plays A Crucial Role In The Development And Physiological Functioning Of The Central Nervous System (Cns). Some Of Its Functions Are To Regulate Cytoarchitecture And Neuronal Growth, For Which Its Receptors Are Widely Distributed In The Cns. Hypothyroidism, Hyperthyroidism And Subclinical Conditions Are The Most Common Endocrine Dysfunction In Our Population. Numerous Neurological Diseases Occur Due To Structural Changes In Neuronal Connections And The Molecular Mechanisms For These Structural Alterations Are Still Poorly Understood, But Studies Suggest The Role Of Axonal-Oriented Proteins In This Disease-Triggering Process. Semaphorins Are Part Of This Group Of Proteins Responsible For Axonal Orientation And Are Known For The Functions Of Guiding Axonal Development During Neuronal Growth, Cytoskeletal Organization, Neural Connectivity And Vascularization. Semaphorins May Also Be Involved In Maintaining Neuronal Stability, Limiting The Formation Of Spontaneous Or AberrantA Ação Dos Hormônios Tireoidianos (Hts) Tem Um Papel Crucial No Desenvolvimento E Funcionamento Fisiológico Do Sistema Nervoso Central (Snc). Algumas De Suas Funções São Regular A Citoarquitetura E Crescimento Neuronal, Para Isso Seus Receptores Estão Amplamente Distribuídos No Snc. O Hipotireoidismo, Hipertireoidismo E As Condições Subclínicas São As Disfunções Endócrinas Mais Comuns Na Nossa População. Inúmeras Doenças Neurológicas Ocorrem Devido Às Mudanças Estruturais Nas Conexões Neuronais E Os Mecanismos Moleculares Para Estas Alterações Estruturais, Ainda É Pouco Compreendido, Mas Estudos Sugerem O Papel Das Proteínas De Orientação Axonal Neste Processo Desencadeador Da Doença. As Semaforinas Fazem Parte Deste Grupo De Proteínas Responsáveis Pela Orientação Axonal E São Conhecidas Pelas Funções De Guiar O Desenvolvimento Axonal Durante O Crescimento Neuronal, Organização Do Citoesqueleto, Conectividade Neural E Vascularização. As Semaforinas Também Podem Está Envolvidas Na Manutenção Da Estabilidade NeDados abertos - Sucupira - Teses e dissertações (2018

The hypothyroid brain

  The thyroid gland is controlled by a feedback system, the hypothalamus-pituitary-thyroid axis, and produces thyroid hormone (TH), which plays a critical role in growth, development and cellular metabolism. Diseases of the thyroid are well defined clinically and biochemically and diseases affecting thyroid function can cause both clinical hypothyroidisms, the most common cause of thyroid dysfunction, occurs when there is a decrease in the production of thyroid hormones, and hyperthyroidism, when there is an increase in hormone production. Common systemic manifestations of hypothyroidism include fatigue, dry skin, weight gain, hair loss, cold intolerance, hoarseness and constipation. Patients affected by this condition present a number of central and peripheral signs in the nervous system that may be neurological manifestations that occur along with the systemic disease. The conversion of thyroid hormone in the target tissue is done by three distinct deiodinases: type I, type II and type III. Each deiodinase has a different function in order to maintain thyroid hormone homeostasis in the tissues. Other proteins important for thyroid state are the TH transporters. MCT8, OATP1C1 and LAT1 and 2 transporters regulate T4 and T3 flow in the cells. The action of THs depends on the interaction of several proteins that are specialized in the control of thyroid hormone homeostasis not only in the brain but also in various tissues. THs are important for the maturation of the brain from the intrauterine period and remain important to adulthood. When there is some disturbance in the control mechanisms for the state of thyroid hormone, the consequences to the tissues, especially the CNS, can range from mild damage to severe impairment in neuronal development

Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora