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Mapping the genomic architecture of complex disease has been predicated on the understanding that genetic variants influence disease risk through modifying gene expression. However, recent discoveries have revealed that a significant burden of disease heritability in common autoinflammatory disorders and coronary artery disease is mediated through genetic variation modifying post-transcriptional modification of RNA through adenosine-to-inosine (A-to-I) RNA editing. This common RNA modification is catalyzed by ADAR enzymes, where ADAR1 edits specific immunogenic double stranded RNA (dsRNA) to prevent activation of the double strand RNA (dsRNA) sensor MDA5 ( IFIH1 ) and stimulation of an interferon stimulated gene (ISG) response. Multiple lines of human genetic data indicate impaired RNA editing and increased dsRNA sensing to be an important mechanism of coronary artery disease (CAD) risk. Here, we provide a crucial link between observations in human genetics and mechanistic cell biology leading to progression of CAD. Through analysis of human atherosclerotic plaque, we implicate the vascular smooth muscle cell (SMC) to have a unique requirement for RNA editing, and that ISG induction occurs in SMC phenotypic modulation, implicating MDA5 activation. Through culture of human coronary artery SMCs, generation of a conditional SMC specific Adar1 deletion mouse model on a pro-atherosclerosis background, and with incorporation of single cell RNA sequencing cellular profiling, we further show that Adar1 controls SMC phenotypic state, is required to maintain vascular integrity, and controls progression of atherosclerosis and vascular calcification. Through this work, we describe a fundamental mechanism of CAD, where cell type and context specific RNA editing and sensing of dsRNA mediates disease progression, bridging our understanding of human genetics and disease causality.
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OBJECTIVE: The goal of this review is to discuss the implementation of genome-wide association studies to identify causal mechanisms of vascular disease risk. APPROACH AND RESULTS: The history of genome-wide association studies is described, the use of imputation and the creation of consortia to conduct meta-analyses with sufficient power to arrive at consistent associated loci for vascular disease. Genomic methods are described that allow the identification of causal variants and causal genes and how they impact the disease process. The power of single-cell analyses to promote genome-wide association studies of causal gene function is described. CONCLUSIONS: Genome-wide association studies represent a paradigm shift in the study of cardiovascular disease, providing identification of genes, cellular phenotypes, and disease pathways that empower the future of targeted drug development.
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Doenças Cardiovasculares , Doenças Vasculares , Humanos , Estudo de Associação Genômica Ampla , Genômica , Desenvolvimento de MedicamentosRESUMO
Extracellular vesicles (EVs) released from healthy endothelial cells (ECs) have shown potential for promoting angiogenesis, but their therapeutic efficacy remains poorly understood. We have previously shown that transplantation of a human embryonic stem cell-derived endothelial cell product (hESC-ECP), promotes new vessel formation in acute ischemic disease in mice, likely via paracrine mechanism(s). Here, we demonstrated that EVs from hESC-ECPs (hESC-eEVs) significantly increased EC tube formation and wound closure in vitro at ultralow doses, whereas higher doses were ineffective. More important, EVs isolated from the mesodermal stage of the differentiation (hESC-mEVs) had no effect. Small RNA sequencing revealed that hESC-eEVs have a unique transcriptomic profile and are enriched in known proangiogenic microRNAs (miRNAs, miRs). Moreover, an in silico analysis identified three novel hESC-eEV-miRNAs with potential proangiogenic function. Differential expression analysis suggested that two of those, miR-4496 and miR-4691-5p, are highly enriched in hESC-eEVs. Overexpression of miR-4496 or miR-4691-5p resulted in increased EC tube formation and wound closure in vitro, validating the novel proangiogenic function of these miRNAs. In summary, we demonstrated that hESC-eEVs are potent inducers of EC angiogenic response at ultralow doses and contain a unique EV-associated miRNA repertoire, including miR-4496 and miR-4691-5p, with novel proangiogenic function.
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Vesículas Extracelulares , MicroRNAs , Humanos , Animais , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Células Endoteliais/metabolismo , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Diferenciação Celular/genética , Células-Tronco/metabolismoRESUMO
Genome wide association studies for coronary artery disease (CAD) have identified a risk locus at 11q22.3. Here, we verify with mechanistic studies that rs2019090 and PDGFD represent the functional variant and gene at this locus. Further, FOXC1/C2 transcription factor binding at rs2019090 is shown to promote PDGFD transcription through the CAD promoting allele. With single cell transcriptomic and histology studies with Pdgfd knockdown in an SMC lineage tracing male atherosclerosis mouse model we find that Pdgfd promotes expansion, migration, and transition of SMC lineage cells to the chondromyocyte phenotype. Pdgfd also increases adventitial fibroblast and pericyte expression of chemokines and leukocyte adhesion molecules, which is linked to plaque macrophage recruitment. Despite these changes there is no effect of Pdgfd deletion on overall plaque burden. These findings suggest that PDGFD mediates CAD risk by promoting deleterious phenotypic changes in SMC, along with an inflammatory response that is primarily focused in the adventitia.
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Aterosclerose , Doença da Artéria Coronariana , Animais , Masculino , Camundongos , Alelos , Aterosclerose/genética , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/patologia , Estudo de Associação Genômica Ampla , Ligação ProteicaRESUMO
Platelet derived growth factor (PDGF) signaling has been extensively studied in the context of vascular disease, but the genetics of this pathway remain to be established. Genome wide association studies (GWAS) for coronary artery disease (CAD) have identified a risk locus at 11q22.3, and we have verified with fine mapping approaches that the regulatory variant rs2019090 and PDGFD represent the functional variant and putative functional gene. Further, FOXC1/C2 transcription factor (TF) binding at rs2019090 was found to promote PDGFD transcription through the CAD promoting allele. Employing a constitutive Pdgfd knockout allele along with SMC lineage tracing in a male atherosclerosis mouse model we mapped single cell transcriptomic, cell state, and lesion anatomical changes associated with gene loss. These studies revealed that Pdgfd promotes expansion, migration, and transition of SMC lineage cells to the chondromyocyte phenotype and vascular calcification. This is in contrast to protective CAD genes TCF21, ZEB2, and SMAD3 which we have shown to promote the fibroblast-like cell transition or perturb the pattern or extent of transition to the chondromyocyte phenotype. Further, Pdgfd expressing fibroblasts and pericytes exhibited greater expression of chemokines and leukocyte adhesion molecules, consistent with observed increased macrophage recruitment to the plaque. Despite these changes there was no effect of Pdgfd deletion on SMC contribution to the fibrous cap or overall lesion burden. These findings suggest that PDGFD mediates CAD risk through promoting SMC expansion and migration, in conjunction with deleterious phenotypic changes, and through promoting an inflammatory response that is primarily focused in the adventitia where it contributes to leukocyte trafficking to the diseased vessel wall.
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BACKGROUND: Smooth muscle cells (SMC), the major cell type in atherosclerotic plaques, are vital in coronary artery diseases (CADs). SMC phenotypic transition, which leads to the formation of various cell types in atherosclerotic plaques, is regulated by a network of genetic and epigenetic mechanisms and governs the risk of disease. The involvement of long noncoding RNAs (lncRNAs) has been increasingly identified in cardiovascular disease. However, SMC lncRNAs have not been comprehensively characterized, and their regulatory role in SMC state transition remains unknown. METHODS: A discovery pipeline was constructed and applied to deeply strand-specific RNA sequencing from perturbed human coronary artery SMC with different disease-related stimuli, to allow for the detection of novel lncRNAs. The functional relevance of a select few novel lncRNAs were verified in vitro. RESULTS: We identified 4579 known and 13 655 de novo lncRNAs in human coronary artery SMC. Consistent with previous long noncoding RNA studies, these lncRNAs overall have fewer exons, are shorter in length than protein-coding genes (pcGenes), and have relatively low expression level. Genomic location of these long noncoding RNA is disproportionately enriched near CAD-related TFs (transcription factors), genetic loci, and gene regulators of SMC identity, suggesting the importance of their function in disease. Two de novo lncRNAs, ZIPPOR (ZEB-interacting suppressor) and TNS1-AS2 (TNS1-antisense 2), were identified by our screen. Combining transcriptional data and in silico modeling along with in vitro validation, we identified CAD gene ZEB2 as a target through which these lncRNAs exert their function in SMC phenotypic transition. CONCLUSIONS: Expression of a large and diverse set of lncRNAs in human coronary artery SMC are highly dynamic in response to CAD-related stimuli. The dynamic changes in expression of these lncRNAs correspond to alterations in transcriptional programs that are relevant to CAD, suggesting a critical role for lncRNAs in SMC phenotypic transition and human atherosclerotic disease.
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Placa Aterosclerótica , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/metabolismo , Placa Aterosclerótica/metabolismo , Fatores de Transcrição/metabolismo , Fenótipo , Miócitos de Músculo Liso/metabolismoRESUMO
Lipidomics represent a valid complementary tool to the biochemical analysis of plasma in humans. However, in cetaceans, these tools have been unexplored. Here, we evaluated how the plasma lipid composition of Tursiops truncatus is modulated by developmental stage and sex, aiming at a potential use of lipidomics in integrated strategies to monitor cetacean health. We characterized the fatty acid profile and detected a total of 26 fatty acids in T. truncatus plasma. The most abundant fatty acids were palmitic acid (C16:0), stearic acid (C18:0) and oleic acid (C18:1n-9). Interestingly, there are consistent differences between the fatty acid profile of mature female and mature male specimens. Phospholipidome analysis identified 320 different lipid species belonging to phosphatidylcholine (PC, 105 lipid species), lysophosphatidylcholine (42), phosphatidylethanolamine (PE, 67), lysophosphatidylethanolamine (18), phosphatidylglycerol (14), lysophosphatidylglycerol (8), phosphatidylinositol (14), lysophosphatidylinositol (2), phosphatidylserine (3), sphingomyelin (45) and ceramides (2) classes. The statistical analysis of the phospholipidome showed that its composition allows discriminating mature animals between sexes and mature males from immature males. Notably, discrimination between sexes is mainly determined by the contents of PE plasmalogens and lysophospholipids (LPC and LPE), while the differences between mature and immature male animals were mainly determined by the levels of PC lipids. This is the first time that a correlation between developmental stage and sex and the lipid composition of the plasma has been established in cetaceans. Being able to discern between age and sex-related changes is an encouraging step towards using these tools to also detect differences related to disease/dysfunction processes.
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Golfinho Nariz-de-Garrafa , Humanos , Animais , Masculino , Feminino , Ácidos Graxos , Lisofosfatidilcolinas , CeramidasRESUMO
Here, we review the highlights of cardiovascular basic science published in 2021 and early 2022 on behalf of the European Society of Cardiology Council for Basic Cardiovascular Science. We begin with non-coding RNAs which have emerged as central regulators cardiovascular biology, and then discuss how technological developments in single-cell 'omics are providing new insights into cardiovascular development, inflammation, and disease. We also review recent discoveries on the biology of extracellular vesicles in driving either protective or pathogenic responses. The Nobel Prize in Physiology or Medicine 2021 recognized the importance of the molecular basis of mechanosensing and here we review breakthroughs in cardiovascular sensing of mechanical force. We also summarize discoveries in the field of atherosclerosis including the role of clonal haematopoiesis of indeterminate potential, and new mechanisms of crosstalk between hyperglycaemia, lipid mediators, and inflammation. The past 12 months also witnessed major advances in the field of cardiac arrhythmia including new mechanisms of fibrillation. We also focus on inducible pluripotent stem cell technology which has demonstrated disease causality for several genetic polymorphisms in long-QT syndrome and aortic valve disease, paving the way for personalized medicine approaches. Finally, the cardiovascular community has continued to better understand COVID-19 with significant advancement in our knowledge of cardiovascular tropism, molecular markers, the mechanism of vaccine-induced thrombotic complications and new anti-viral therapies that protect the cardiovascular system.
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COVID-19 , Doenças Cardiovasculares , Sistema Cardiovascular , Humanos , Medicina de Precisão , Biomarcadores , Inflamação , Lipídeos , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/terapiaRESUMO
AIMS: Endothelial cell (EC) dysfunction drives the initiation and pathogenesis of pulmonary arterial hypertension (PAH). We aimed to characterize EC dynamics in PAH at single-cell resolution. METHODS AND RESULTS: We carried out single-cell RNA sequencing (scRNA-seq) of lung ECs isolated from an EC lineage-tracing mouse model in Control and SU5416/hypoxia-induced PAH conditions. EC populations corresponding to distinct lung vessel types, including two discrete capillary populations, were identified in both Control and PAH mice. Differential gene expression analysis revealed global PAH-induced EC changes that were confirmed by bulk RNA-seq. This included upregulation of the major histocompatibility complex class II pathway, supporting a role for ECs in the inflammatory response in PAH. We also identified a PAH response specific to the second capillary EC population including upregulation of genes involved in cell death, cell motility, and angiogenesis. Interestingly, four genes with genetic variants associated with PAH were dysregulated in mouse ECs in PAH. To compare relevance across PAH models and species, we performed a detailed analysis of EC heterogeneity and response to PAH in rats and humans through whole-lung PAH scRNA-seq datasets, revealing that 51% of up-regulated mouse genes were also up-regulated in rat or human PAH. We identified promising new candidates to target endothelial dysfunction including CD74, the knockdown of which regulates EC proliferation and barrier integrity in vitro. Finally, with an in silico cell ordering approach, we identified zonation-dependent changes across the arteriovenous axis in mouse PAH and showed upregulation of the Serine/threonine-protein kinase Sgk1 at the junction between the macro- and microvasculature. CONCLUSION: This study uncovers PAH-induced EC transcriptomic changes at a high resolution, revealing novel targets for potential therapeutic candidate development.
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Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Animais , Células Endoteliais/metabolismo , Hipertensão Pulmonar Primária Familiar/metabolismo , Humanos , Camundongos , Hipertensão Arterial Pulmonar/genética , Artéria Pulmonar , Ratos , Análise de Sequência de RNARESUMO
INTRODUCTION: Breast volume estimation is considered crucial for breast cancer surgery planning. A single, easy, and reproducible method to estimate breast volume is not available. This study aims to evaluate, in patients proposed for mastectomy, the accuracy of the calculation of breast volume from a low-cost 3D surface scan (Microsoft Kinect) compared to the breast MRI and water displacement technique. MATERIAL AND METHODS: Patients with a Tis/T1-T3 breast cancer proposed for mastectomy between July 2015 and March 2017 were assessed for inclusion in the study. Breast volume calculations were performed using a 3D surface scan and the breast MRI and water displacement technique. Agreement between volumes obtained with both methods was assessed with the Spearman and Pearson correlation coefficients. RESULTS: Eighteen patients with invasive breast cancer were included in the study and submitted to mastectomy. The level of agreement of the 3D breast volume compared to surgical specimens and breast MRI volumes was evaluated. For mastectomy specimen volume, an average (standard deviation) of 0.823 (0.027) and 0.875 (0.026) was obtained for the Pearson and Spearman correlations, respectively. With respect to MRI annotation, we obtained 0.828 (0.038) and 0.715 (0.018). DISCUSSION: Although values obtained by both methodologies still differ, the strong linear correlation coefficient suggests that 3D breast volume measurement using a low-cost surface scan device is feasible and can approximate both the MRI breast volume and mastectomy specimen with sufficient accuracy. CONCLUSION: 3D breast volume measurement using a depth-sensor low-cost surface scan device is feasible and can parallel MRI breast and mastectomy specimen volumes with enough accuracy. Differences between methods need further development to reach clinical applicability. A possible approach could be the fusion of breast MRI and the 3D surface scan to harmonize anatomic limits and improve volume delimitation.
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Neoplasias da Mama , Mama/diagnóstico por imagem , Mama/cirurgia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Feminino , Humanos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Mastectomia/métodosRESUMO
Plasma biochemical analysis remains one of the established ways of monitoring captive marine mammal health. More recently, complementary plasma lipidomic analysis has proven to be a valid tool in disease diagnosis and prevention, with the potential to validate and complement common biochemical analysis, providing a more integrative approach. In this study, we thoroughly characterized the plasma polar lipid content of Tursiops truncatus, the most common cetacean species held under human care. Our results showed that phosphatidylcholine, lysophosphatidylcholine, and sphingomyelins (CerPCho) are the most represented phospholipid classes in T. truncatus plasma. Palmitic, oleic, and stearic acids are the major fatty acid (FA) present esterified to the plasma polar lipids of this species, although some n-3 species are also remarkably present, namely eicosapentaenoic and docosahexaenoic acids. The polar lipidome identified by HILIC LC-MS allowed identifying 304 different lipid species. These species belong to the phosphatidylcholine (103 lipid species), lysophosphatidylcholine (35), phosphatidylethanolamine (71), lysophosphatidylethanolamine (20), phosphatidylglycerol (13), lysophosphatidylglycerol (5), phosphatidylinositol (15), lysophosphatidylinositol (3), phosphatidylserine (6) lysophosphatidylserine (1), and sphimgomyelin (32) classes. This was the first time that the dolphin plasma phospholipid profile was characterized, providing a knowledge that will be important to further understand lipid metabolism and physiological regulation in small cetaceans. Furthermore, this study proved the practicability of the use of plasma lipid profiling for health assessment in marine mammals under human care.
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Golfinho Nariz-de-Garrafa , Animais , Ácidos Graxos , Lipidômica , Espectrometria de Massas , FosfatidilcolinasRESUMO
[Figure: see text].
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Transição Epitelial-Mesenquimal , Hipertensão Pulmonar/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/patologia , Camundongos , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , RNA Longo não Codificante/genética , Transcriptoma , Remodelação VascularRESUMO
Brown seaweeds are known to present components with appealing bioactive properties eliciting great interest for industrial applications. However, their lipid content is generally disregarded beyond their fatty acid (FA) composition. This study thoroughly characterized the lipid profile of two brown seaweeds collected from Portuguese coast, the native Bifurcaria bifurcata and the invasive Sargassum muticum species, and bioprospecting for antioxidant activity. An integrated state-of-the-art approach including gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (HILIC-ESI-MS/MS), allowed a comprehensive picture of FA and polar lipid content. Polar lipid profile of B. bifurcata and S. muticum included 143 and 217 lipid species respectively, distributed between glycolipids, phospholipids, and betaine lipids. Some of the lipid species found have been assigned biological activity and contain of n-3 and n-6 FA. Sargassum muticum presented the highest n-3 FA content. Low concentrations of extracts of both seaweeds displayed antioxidant activity, with S. muticum presenting more promising results. These findings contribute to the nutritional and industrial exploitation of both seaweeds, highlighting their relevance as viable sources of bioactive and added-value compounds. Sargassum muticum presented interesting lipid composition and bioactivity, which may represent an accessible opportunity for the exploitation of this invasive seaweed, especially taking advantage of Sargassum blooms.
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The aquaculture of macroalgae for human consumption and other high-end applications is experiencing unprecedented development in European countries, with the brown algae Saccharina latissima being the flag species. However, environmental conditions in open sea culture sites are often unique, which may impact the biochemical composition of cultured macroalgae. The present study compared the elemental compositions (CHNS), fatty acid profiles, and lipidomes of S. latissima originating from three distinct locations (France, Norway, and the United Kingdom). Significant differences were found in the elemental composition, with Norwegian samples displaying twice the lipid content of the others, and significantly less protein (2.6%, while French and UK samples contained 6.3% and 9.1%, respectively). The fatty acid profiles also differed considerably, with UK samples displaying a lower content of n-3 fatty acids (21.6%), resulting in a higher n-6/n-3 ratio. Regarding the lipidomic profile, samples from France were enriched in lyso lipids, while those from Norway displayed a particular signature of phosphatidylglycerol, phosphatidylinositol, and phosphatidylcholine. Samples from the UK featured higher levels of phosphatidylethanolamine and, in general, a lower content of galactolipids. These differences highlight the influence of site-specific environmental conditions in the shaping of macroalgae biochemical phenotypes and nutritional value. It is also important to highlight that differences recorded in the lipidome of S. latissima make it possible to pinpoint specific lipid species that are likely to represent origin biomarkers. This finding is relevant for future applications in the field of geographic origin traceability and food control.
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Lipídeos/química , Phaeophyceae/química , Phaeophyceae/metabolismo , Aquicultura/métodos , Europa (Continente) , Ácidos Graxos/análise , Ácidos Graxos/química , Lipidômica/métodos , Espectrometria de Massas/métodos , Oceanos e Mares , Phaeophyceae/genética , Filogeografia/métodos , Alga Marinha/química , Alga Marinha/crescimento & desenvolvimento , Alga Marinha/metabolismoRESUMO
Present throughout the vasculature, endothelial cells (ECs) are essential for blood vessel function and play a central role in the pathogenesis of diverse cardiovascular diseases. Understanding the intricate molecular determinants governing endothelial function and dysfunction is essential to develop novel clinical breakthroughs and improve knowledge. An increasing body of evidence demonstrates that long non-coding RNAs (lncRNAs) are active regulators of the endothelial transcriptome and function, providing emerging insights into core questions surrounding EC contributions to pathology, and perhaps the emergence of novel therapeutic opportunities. In this review, we discuss this class of non-coding transcripts and their role in endothelial biology during cardiovascular development, homeostasis, and disease, highlighting challenges during discovery and characterization and how these have been overcome to date. We further discuss the translational therapeutic implications and the challenges within the field, highlighting lncRNA that support endothelial phenotypes prevalent in cardiovascular disease.
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Doenças Cardiovasculares/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/fisiopatologia , Endotélio Vascular/fisiopatologia , Regulação da Expressão Gênica , Humanos , RNA Longo não Codificante/genética , Transdução de SinaisRESUMO
Breast cancer is one of the most common malignancies affecting women worldwide. However, despite its incidence trends have increased, the mortality rate has significantly decreased. The primary concern in any cancer treatment is the oncological outcome but, in the case of breast cancer, the surgery aesthetic result has become an important quality indicator for breast cancer patients. In this sense, an adequate surgical planning and prediction tool would empower the patient regarding the treatment decision process, enabling a better communication between the surgeon and the patient and a better understanding of the impact of each surgical option. To develop such tool, it is necessary to create complete 3D model of the breast, integrating both inner and outer breast data. In this review, we thoroughly explore and review the major existing works that address, directly or not, the technical challenges involved in the development of a 3D software planning tool in the field of breast conserving surgery.
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Neoplasias da Mama/diagnóstico , Neoplasias da Mama/cirurgia , Mama/diagnóstico por imagem , Imageamento Tridimensional/métodos , Mastectomia Segmentar/métodos , Mama/patologia , Feminino , Humanos , Planejamento de Assistência ao Paciente , Período Pré-Operatório , SoftwareRESUMO
T-cell division is central to maintaining a stable T-cell pool in adults. It also enables T-cell expansion in neonates, and after depletion by chemotherapy, bone marrow transplantation, or infection. The same signals required for T-cell survival in lymphoreplete settings, IL-7 and T-cell receptor (TCR) interactions with self-peptide MHC (pMHC), induce division when T-cell numbers are low. The strength of reactivity for self-pMHC has been shown to correlate with the capacity of T cells to undergo lymphopenia-induced proliferation (LIP), in that weakly self-reactive T cells are unable to divide, implying that T-cell reconstitution would significantly skew the TCR repertoire toward TCRs with greater self-reactivity and thus compromise T-cell diversity. Here, we show that while CD4+ T cells with low self-pMHC reactivity experience more intense competition, they are able to divide when present at low enough cell numbers. Thus, at physiological precursor frequencies CD4+ T cells with low self-pMHC reactivity are able to contribute to the reconstitution of the T-cell pool.
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Autoimunidade , Subpopulações de Linfócitos T/imunologia , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Biomarcadores , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Proliferação de Células , Células Clonais , Expressão Gênica , Homeostase , Imunofenotipagem , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Linfopenia/imunologia , Complexo Principal de Histocompatibilidade/imunologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Fenótipo , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/metabolismoRESUMO
Methylxanthines are a group of phytochemicals derived from the purine base xanthine and obtained from plant secondary metabolism. They are unobtrusively included in daily diet in common products as coffee, tea, energetic drinks, or chocolate. Caffeine is by far the most studied methylxanthine either in animal or epidemiologic studies. Theophylline and theobromine are other relevant methylxanthines also commonly available in the aforementioned sources. There are many disseminated myths about methylxanthines but there is increased scientific knowledge to discuss all the controversy and promise shown by these intriguing phytochemicals. In fact, many beneficial physiologic outcomes have been suggested for methylxanthines in areas as important and diverse as neurodegenerative and respiratory diseases, diabetes or cancer. However, there have always been toxicity concerns with methylxanthine (over)consumption and pharmacologic applications. Herein, we explore the structure-bioactivity relationships to bring light those enumerated effects. The potential shown by methylxanthines in such a wide range of conditions should substantiate many other scientific endeavors that may highlight their adequacy as adjuvant therapy agents and may contribute to the advent of functional foods. Newly designed targeted molecules based on methylxanthine structure may originate more specific and effective outcomes.
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Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Xantinas/química , Xantinas/farmacologia , Animais , Cacau/química , Cafeína/química , Cafeína/farmacologia , Humanos , Estrutura Molecular , Metabolismo Secundário , Relação Estrutura-Atividade , Teobromina/química , Teobromina/farmacologia , Teofilina/química , Teofilina/farmacologiaRESUMO
The vitreous humor (VH) is the largest component of the eye. It is a colorless, gelatinous, highly hydrated matrix that fills the posterior segment of the eye between the lens and retina in vertebrates. In VH, a diversity of proteins that can influence retinal physiology is present, including growth factors, hormones, proteins with transporter activity, and enzymes. More importantly, the protein composition of VH has been described as being altered in a number of disease states. Therefore, attempts aiming at establishing a map of VH proteins and detecting putative biomarkers for ocular illness or protein fluctuations with putative physiologic significance were conducted over the last two decades, using proteomic approaches. Proteomic strategies often involve gel-based or LC techniques as sample fractioning approaches, subsequently coupled with MS procedures. This set of studies resulted in the proteomic characterization of a range of ocular disease samples, with particular incidence on diabetic retinopathy. However, practical therapeutic applications arising from these studies are scarce at the moment. A pertinent example of therapeutic targets arising from VH proteomics has emerged concerning vasoproliferative factors present in the vitreous, which should be involved in neovascularization and subsequent fibrovascular proliferation of the retina, in ocular disease context. Therefore, this review attempts to sum up the information acquired from the proteomic approaches to ocular disease conducted in VH samples, highlighting its clinical potential for disclosing ocular disease mechanisms and engendering pharmacological therapeutic treatments.
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Biomarcadores/metabolismo , Oftalmopatias/diagnóstico , Proteínas do Olho/análise , Proteoma/análise , Proteômica/métodos , Corpo Vítreo/metabolismo , Corpo Vítreo/patologia , Animais , Líquidos Corporais/química , Oftalmopatias/metabolismo , Humanos , Cristalino , Neovascularização PatológicaRESUMO
To support effective host defense, the T cell repertoire must balance breadth of recognition with sensitivity for antigen. The concept that T lymphocytes are positively selected in the thymus is well established, but how this selection achieves such a repertoire has not been resolved. Here we suggest that it is direct linkage between self and foreign antigen recognition that produces the necessary blend of TCR diversity and specificity in the mature peripheral repertoire, enabling responses to a broad universe of unpredictable antigens while maintaining an adequate number of highly sensitive T cells in a population of limited size. Our analysis also helps to explain how diversity and frequency of antigen-reactive cells in a T cell repertoire are adjusted in animals of vastly different size scale to enable effective antipathogen responses and suggests a possible binary architecture in the TCR repertoire that is divided between germline-related optimal binding and diverse recognition.