JOSE EDUARDO KRIEGER
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Cardio-Pneumologia, Faculdade de Medicina - Docente
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina
LIM/13 - Laboratório de Genética e Cardiologia Molecular, Hospital das Clínicas, Faculdade de Medicina - Líder
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina
LIM/13 - Laboratório de Genética e Cardiologia Molecular, Hospital das Clínicas, Faculdade de Medicina - Líder
12 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 12
- Focal adhesion signaling: Vascular smooth muscle cell contractility beyond calcium mechanisms(2021) RIBEIRO-SILVA, J. C.; MIYAKAWA, A. A.; KRIEGER, J. E.Smooth muscle cell (SMC) contractility is essential to vessel tone maintenance and blood pressure regulation. In response to vasoconstrictors, calcium-dependent mechanisms promote the activation of the regulatory myosin light chain, leading to increased cytoskeleton tension that favors cell shortening. In contrast, SMC maintain an intrinsic level of a contractile force independent of vasoconstrictor stimulation and sustained SMC contraction beyond the timescale of calcium-dependent mechanisms suggesting the involvement of additional players in the contractile response. Focal adhesions (FAs) are conceivable candidates that may influence SMC contraction. They are required for actin-based traction employed by cells to sense and respond to environmental cues in a process termed mechanotransduction. Depletion of FA proteins impairs SMC contractility, producing arteries that are prone to dissection because of a lack of mechanical stability. Here, we discuss the role of calcium-independent FA signaling mechanisms in SMC contractility. We speculate that FA signaling contributes to the genesis of a variety of SMC phenotypes and discuss the potential implications for mechanical homeostasis in normal and diseased states. ©2021 The Author(s).
- Non-HFE hemochromatosis(2012) SANTOS, Paulo Caleb Júnior de Lima; DINARDO, Carla Luana; CANÇADO, Rodolfo Delfini; SCHETTERT, Isolmar Tadeu; KRIEGER, José Eduardo; PEREIRA, Alexandre CostaHereditary hemochromatosis (HH) is an autosomal recessive disorder classically related to HFE mutations. However, since 1996, it is known that HFE mutations explain about 80% of HH cases, with the remaining around 20% denominated non-HFE hemochromatosis. Nowadays, four main genes are implicated in the pathophysiology of clinical syndromes classified as non-HFE hemochromatosis: hemojuvelin (HJV, type 2Ajuvenile HH), hepcidin (HAMP, type 2B juvenile HH), transferrin receptor 2 (TFR2, type 3 HH) and ferroportin (SLC40A1, type 4 HH). The aim of this review is to explore molecular, clinical and management aspects of non-HFE hemochromatosis.
- Dynamic Crosstalk between Vascular Smooth Muscle Cells and the Aged Extracellular Matrix(2021) RIBEIRO-SILVA, Joao Carlos; NOLASCO, Patricia; KRIEGER, Jose Eduardo; MIYAKAWA, Ayumi AureaVascular aging is accompanied by the fragmentation of elastic fibers and collagen deposition, leading to reduced distensibility and increased vascular stiffness. A rigid artery facilitates elastin to degradation by MMPs, exposing vascular cells to greater mechanical stress and triggering signaling mechanisms that only exacerbate aging, creating a self-sustaining inflammatory environment that also promotes vascular calcification. In this review, we highlight the role of crosstalk between smooth muscle cells and the vascular extracellular matrix (ECM) and how aging promotes smooth muscle cell phenotypes that ultimately lead to mechanical impairment of aging arteries. Understanding the underlying mechanisms and the role of associated changes in ECM during aging may contribute to new approaches to prevent or delay arterial aging and the onset of cardiovascular diseases.
- Genetics of Resistant Hypertension: the Missing Heritability and Opportunities(2018) TEIXEIRA, Samantha K.; PEREIRA, Alexandre C.; KRIEGER, Jose E.Blood pressure regulation in humans has long been known to be a genetically determined trait. The identification of causal genetic modulators for this trait has been unfulfilling at the least. Despite the recent advances of genome-wide genetic studies, loci associated with hypertension or blood pressure still explain a very low percentage of the overall variation of blood pressure in the general population. This has precluded the translation of discoveries in the genetics of human hypertension to clinical use. Here, we propose the combined use of resistant hypertension as a trait for mapping genetic determinants in humans and the integration of new large-scale technologies to approach in model systems the multidimensional nature of the problem. New large-scale efforts in the genetic and genomic arenas are paving the way for an increased and granular understanding of genetic determinants of hypertension. New technologies for whole genome sequence and large-scale forward genetic screens can help prioritize gene and gene-pathways for downstream characterization and large-scale population studies, and guided pharmacological design can be used to drive discoveries to the translational application through better risk stratification and new therapeutic approaches. Although significant challenges remain in the mapping and identification of genetic determinants of hypertension, new large-scale technological approaches have been proposed to surpass some of the shortcomings that have limited progress in the area for the last three decades. The incorporation of these technologies to hypertension research may significantly help in the understanding of inter-individual blood pressure variation and the deployment of new phenotyping and treatment approaches for the condition.
- Missi ng links in preeclampsia cell model systems of endothelial dysfunction(2023) VIANA-MATTIOLI, Sarah; FONSECA-ALANIZ, Miriam Helena; PINHEIRO-DE-SOUSA, Iguaracy; KRIEGER, Jose Eduardo; SANDRIM, Valeria CristinaPreeclampsia, one of the main hypertensive disorders of pregnancy, is associated with circulating factors released by the ischemic placenta accompanied by systemic endothelial dysfunction. The etiology of preeclampsia remains poorly understood although it is associated with high maternal and fetal mortality and increased cardiovascular disease risk. Most cell model systems used for studying endothelial dysfunction have not taken into account hemodynamic physical factors such as shear-stress forces which may prevent extrapolation of cell data to in vivo settings. We overview the role of hemodynamic forces in modulating endothelial cell function and discuss strategies to reproduce this biological characteristic in vitro to improve our understanding of endothelial dysfunction associated with preeclampsia.
- Plasma Ceramides in Cardiovascular Disease Risk Stratification(2022) JUNQUEIRA, Debora L. M.; STACH, Alline; CAIXETA, Adriano; SALLUM, Juliana; YASAKI, Erika; TSUTSUI, Jeane; RIZATTI, Edgar; ROCHITTE, Carlos E.; Ching-Jianhong; KOVALIK, Jean-Paul; KRIEGER, Jose E.; RICHARDS, A. Mark; CHAN, Mark Y.; CARVALHO, Leonardo P. deCeramide production takes place throughout the body and plays a key role in the maintenance of normal physiology. However, ceramide levels are altered during disease states, particularly considering the development of diabetes and dyslipidemia. Ceramide production is also associated with atherosclerotic plaque instability. Recent studies revealed that patients with unstable coronary artery disease (CAD) presented increased plasma ceramide levels (especially C16, C18, and C24:1). These molecules are currently considered emerging biomarkers of cardiovascular diseases (CVD), being used for predicting atherosclerotic plaque instability and adverse cardiovascular events independently from traditional risk factors. With the aim of describing and discussing the role of ceramides in the stratification of cardiovascular diseases, this narrative review contextualizes the importance of this biomarker in the present cardiology scenario.
- Molecular Diagnostic and Pathogenesis of Hereditary Hemochromatosis(2012) SANTOS, Paulo C. J. L.; KRIEGER, Jose E.; PEREIRA, Alexandre C.Hereditary hemochromatosis (HH) is an autosomal recessive disorder characterized by enhanced intestinal absorption of dietary iron. Without therapeutic intervention, iron overload leads to multiple organ damage such as liver cirrhosis, cardiomyopathy, diabetes, arthritis, hypogonadism and skin pigmentation. Most HH patients carry HFE mutant genotypes: homozygosity for p.Cys282Tyr or p.Cys282Tyr/p.His63Asp compound heterozygosity. In addition to HFE gene, mutations in the genes that encode hemojuvelin (HJV), hepcidin (HAMP), transferrin receptor 2 (TFR2) and ferroportin (SLC40A1) have been associated with regulation of iron homeostasis and development of HH. The aim of this review was to identify the main gene mutations involved in the pathogenesis of type 1, 2, 3 and 4 HH and their genetic testing indication. HFE testing for the two main mutations (p.Cys282Tyr and p.His63Asp) should be performed in all patients with primary iron overload and unexplained increased transferrin saturation and/or serum ferritin values. The evaluation of the HJV p.Gly320Val mutation must be the molecular test of choice in suspected patients with juvenile hemochromatosis with less than 30 years and cardiac or endocrine manifestations. In conclusion, HH is an example that genetic testing can, in addition to performing the differential diagnostic with secondary iron overload, lead to more adequate and faster treatment.
- Before and after AlphaFold2: An overview of protein structure prediction(2023) BERTOLINE, Leticia M. F.; LIMA, Angelica N.; KRIEGER, Jose E.; TEIXEIRA, Samantha K.Three-dimensional protein structure is directly correlated with its function and its determination is critical to understanding biological processes and addressing human health and life science problems in general. Although new protein structures are experimentally obtained over time, there is still a large difference between the number of protein sequences placed in Uniprot and those with resolved tertiary structure. In this context, studies have emerged to predict protein structures by methods based on a template or free modeling. In the last years, different methods have been combined to overcome their individual limitations, until the emergence of AlphaFold2, which demonstrated that predicting protein structure with high accuracy at unprecedented scale is possible. Despite its current impact in the field, AlphaFold2 has limitations. Recently, new methods based on protein language models have promised to revolutionize the protein structural biology allowing the discovery of protein structure and function only from evolutionary patterns present on protein sequence. Even though these methods do not reach AlphaFold2 accuracy, they already covered some of its limitations, being able to predict with high accuracy more than 200 million proteins from metagenomic databases. In this mini-review, we provide an overview of the breakthroughs in protein structure prediction before and after AlphaFold2 emergence.
- Human Mesenchymal Stem Cells: From Immunophenotyping by Flow Cytometry to Clinical Applications(2013) NERY, Arthur A.; NASCIMENTO, Isis C.; GLASER, Talita; BASSANEZE, Vinicius; KRIEGER, Jose E.; ULRICH, HenningModern medicine will unequivocally include regenerative medicine as a major break-through in the re-establishment of damaged or lost tissues due to degenerative diseases or injury. In this scenario, millions of patients worldwide can have their quality of life improved by stem cell implantation coupled with endogenous secretion or administration of survival and differentiation promoting factors. Large efforts, relying mostly on flow cytometry and imaging techniques, have been put into cell isolation, immunophenotyping, and studies of differentiation properties of stem cells of diverse origins. Mesenchymal stem cells (MSCs) are particularly relevant for therapy due to their simplicity of isolation. A minimal phenotypic pattern for the identification of MSCs cells requires them to be immunopositive for CD73, CD90, and CD105 expression, while being negative for CD34, CD45, and HLA-DR and other surface markers. MSCs identified by their cell surface marker expression pattern can be readily purified from patient's bone marrow and adipose tissues. Following expansion and/or predifferentiation into a desired tissue type, stem cells can be reimplanted for tissue repair in the same patient, virtually eliminating rejection problems. Transplantation of MSCs is subject of almost 200 clinical trials to cure and treat a very broad range of conditions, including bone, heart, and neurodegenerative diseases. Immediate or medium term improvements of clinical symptoms have been reported as results of many clinical studies. (C) 2012 International Society for Advancement of Cytometry
- Endothelial Plasticity: Shifting Phenotypes through Force Feedback(2016) KRENNING, Guido; BARAUNA, Valerio G.; KRIEGER, Jose E.; HARMSEN, Martin C.; MOONEN, Jan-Renier A. J.The endothelial lining of the vasculature is exposed to a large variety of biochemical and hemodynamic stimuli with different gradients throughout the vascular network. Adequate adaptation requires endothelial cells to be highly plastic, which is reflected by the remarkable heterogeneity of endothelial cells in tissues and organs. Hemodynamic forces such as fluid shear stress and cyclic strain are strong modulators of the endothelial phenotype and function. Although endothelial plasticity is essential during development and adult physiology, proatherogenic stimuli can induce adverse plasticity which contributes to disease. Endothelial-to-mesenchymal transition (EndMT), the hallmark of endothelial plasticity, was long thought to be restricted to embryonic development but has emerged as a pathologic process in a plethora of diseases. In this perspective we argue how shear stress and cyclic strain can modulate EndMT and discuss how this is reflected in atherosclerosis and pulmonary arterial hypertension.