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1.
Am J Pathol ; 192(1): 160-177, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34710383

RESUMO

Sigma 1 receptor (Sigmar1) is a widely expressed, multitasking molecular chaperone protein that plays functional roles in several cellular processes. Mutations in the Sigmar1 gene are associated with several distal neuropathies with strong manifestation in skeletal muscle dysfunction with phenotypes like muscle wasting and atrophy. However, the physiological function of Sigmar1 in skeletal muscle remains unknown. Herein, the physiological role of Sigmar1 in skeletal muscle structure and function in gastrocnemius, quadriceps, soleus, extensor digitorum longus, and tibialis anterior muscles was determined. Quantification of myofiber cross-sectional area showed altered myofiber size distribution and changes in myofiber type in the skeletal muscle of the Sigmar1-/- mice. Interestingly, ultrastructural analysis by transmission electron microscopy showed the presence of abnormal mitochondria, and immunostaining showed derangements in dystrophin localization in skeletal muscles from Sigmar1-/- mice. In addition, myopathy in Sigmar1-/- mice was associated with an increased number of central nuclei, increased collagen deposition, and fibrosis. Functional studies also showed reduced endurance and exercise capacity in the Sigmar1-/- mice without any changes in voluntary locomotion, markers for muscle denervation, and muscle atrophy. Overall, this study shows, for the first time, a potential physiological function of Sigmar1 in maintaining healthy skeletal muscle structure and function.


Assuntos
Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia , Receptores sigma/deficiência , Animais , Colágeno/metabolismo , Distrofina/metabolismo , Fibrose , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/ultraestrutura , Condicionamento Físico Animal , Transporte Proteico , Receptores sigma/metabolismo
2.
Mitochondrion ; 62: 159-175, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34902622

RESUMO

Sigmar1 is a widely expressed molecular chaperone protein in mammalian cell systems. Accumulating research demonstrated the cardioprotective roles of pharmacologic Sigmar1 activation by ligands in preclinical rodent models of cardiac injury. Extensive biochemical and immuno-electron microscopic research demonstrated Sigmar1's sub-cellular localization largely depends on cell and organ types. Despite comprehensive studies, Sigmar1's direct molecular role in cardiomyocytes remains elusive. In the present study, we determined Sigmar1's subcellular localization, transmembrane topology, and function using complementary microscopy, biochemical, and functional assays in cardiomyocytes. Quantum dots in transmission electron microscopy showed Sigmar1 labeled quantum dots on the mitochondrial membranes, lysosomes, and sarcoplasmic reticulum-mitochondrial interface. Subcellular fractionation of heart cell lysates confirmed Sigmar1's localization in purified mitochondria fraction and lysosome fraction. Immunocytochemistry confirmed Sigmar1 colocalization with mitochondrial proteins in isolated adult mouse cardiomyocytes. Sigmar1's mitochondrial localization was further confirmed by Sigmar1 colocalization with Mito-Tracker in isolated mouse heart mitochondria. A series of biochemical experiments, including alkaline extraction and proteinase K treatment of purified heart mitochondria, demonstrated Sigmar1 as an integral mitochondrial membrane protein. Sigmar1's structural requirement for mitochondrial localization was determined by expressing FLAG-tagged Sigmar1 fragments in cells. Full-length Sigmar1 and Sigmar1's C terminal-deletion fragments were able to localize to the mitochondrial membrane, whereas N-terminal deletion fragment was unable to incorporate into the mitochondria. Finally, functional assays using extracellular flux analyzer and high-resolution respirometry showed Sigmar1 siRNA knockdown significantly altered mitochondrial respiration in cardiomyocytes. Overall, we found that Sigmar1 localizes to mitochondrial membranes and is indispensable for maintaining mitochondrial respiratory homeostasis in cardiomyocytes.


Assuntos
Mitocôndrias Cardíacas/fisiologia , Miócitos Cardíacos/metabolismo , Transporte Proteico/fisiologia , Receptores sigma/metabolismo , Animais , Metabolismo Energético/fisiologia , Feminino , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Masculino , Camundongos , RNA Interferente Pequeno , Ratos , Receptores sigma/genética
3.
Matrix Biol ; 103-104: 1-21, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34537369

RESUMO

The multifunctional glycoprotein fibronectin influences several crucial cellular processes and contributes to multiple pathologies. While a link exists between fibronectin-associated pathologies and the receptor tyrosine kinase EphA2, the mechanism by which EphA2 promotes fibronectin matrix remodeling remains unknown. We previously demonstrated that EphA2 deletion reduces smooth muscle fibronectin deposition and blunts fibronectin deposition in atherosclerosis without influencing fibronectin expression. We now show that EphA2 expression is required for contractility-dependent elongation of tensin- and α5ß1 integrin-rich fibrillar adhesions that drive fibronectin fibrillogenesis. Mechanistically, EphA2 localizes to integrin adhesions where focal adhesion kinase mediates ligand-independent Y772 phosphorylation, and mutation of this site significantly blunts fibrillar adhesion length. EphA2 deficiency decreases smooth muscle cell contractility by enhancing p190RhoGAP activation and reducing RhoA activity, whereas stimulating RhoA signaling in EphA2 deficient cells rescues fibrillar adhesion elongation. Together, these data identify EphA2 as a novel regulator of fibrillar adhesion elongation and provide the first data identifying a role for EphA2 signaling in integrin adhesions.


Assuntos
Fibronectinas , Integrinas , Adesão Celular , Citoesqueleto , Fibronectinas/genética , Adesões Focais , Integrina alfa5beta1 , Integrinas/genética , Transdução de Sinais , Tensinas/genética
4.
J Am Heart Assoc ; 10(17): e015868, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34472367

RESUMO

Background Stress has emerged as an important risk factor for heart disease in women. Stress levels have been shown to correlate with delayed recovery and increased mortality after a myocardial infarction. Therefore, we sought to investigate if the observed sex-specific effects of stress in myocardial infarction may be partly attributed to genomic interactions between the female sex hormones, estrogen (E2), and the primary stress hormones glucocorticoids. Methods and Results Genomewide studies show that glucocorticoids inhibit estrogen-mediated regulation of genes with established roles in cardiomyocyte homeostasis. These include 5-HT2BR (cardiac serotonin receptor 2B), the expression of which is critical to prevent cardiomyocyte death in the adult heart. Using siRNA, gene expression, and chromatin immunoprecipitation assays, we found that 5-HT2BR is a primary target of the glucocorticoid receptor and the estrogen receptor α at the level of transcription. The glucocorticoid receptor blocks the recruitment of estrogen receptor α to the promoter of the 5-HT2BR gene, which may contribute to the adverse effects of stress in the heart of premenopausal women. Using immunoblotting, TUNEL (terminal deoxynucleotidal transferase-mediated biotin-deoxyuridine triphosphate nick-end labeling), and flow cytometry, we demonstrate that estrogen decreases cardiomyocyte death by a mechanism relying on 5-HT2BR expression. In vitro and in vivo experiments show that glucocorticoids inhibit estrogen cardioprotection in response to hypoxia/reoxygenation injury and exacerbate the size of the infarct areas in myocardial infarction. Conclusions These results established a novel mechanism underlying the deleterious effects of stress on female cardiac health in the setting of ischemia/reperfusion.


Assuntos
Estrogênios/metabolismo , Glucocorticoides , Infarto do Miocárdio , Traumatismo por Reperfusão Miocárdica , Receptor 5-HT2B de Serotonina , Apoptose , Morte Celular , Receptor alfa de Estrogênio , Feminino , Glucocorticoides/farmacologia , Humanos , Hipóxia , Masculino , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos , Receptores de Glucocorticoides/genética
5.
Cell Rep ; 36(4): 109420, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34320345

RESUMO

Dysregulated glycine metabolism is emerging as a common denominator in cardiometabolic diseases, but its contribution to atherosclerosis remains unclear. In this study, we demonstrate impaired glycine-oxalate metabolism through alanine-glyoxylate aminotransferase (AGXT) in atherosclerosis. As found in patients with atherosclerosis, the glycine/oxalate ratio is decreased in atherosclerotic mice concomitant with suppression of AGXT. Agxt deletion in apolipoprotein E-deficient (Apoe-/-) mice decreases the glycine/oxalate ratio and increases atherosclerosis with induction of hepatic pro-atherogenic pathways, predominantly cytokine/chemokine signaling and dysregulated redox homeostasis. Consistently, circulating and aortic C-C motif chemokine ligand 5 (CCL5) and superoxide in lesional macrophages are increased. Similar findings are observed following dietary oxalate overload in Apoe-/- mice. In macrophages, oxalate induces mitochondrial dysfunction and superoxide accumulation, leading to increased CCL5. Conversely, AGXT overexpression in Apoe-/- mice increases the glycine/oxalate ratio and decreases aortic superoxide, CCL5, and atherosclerosis. Our findings uncover dysregulated oxalate metabolism via suppressed AGXT as a driver and therapeutic target in atherosclerosis.


Assuntos
Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Terapia de Alvo Molecular , Oxalatos/metabolismo , Animais , Aorta/metabolismo , Apolipoproteínas E/deficiência , Apolipoproteínas E/metabolismo , Ácidos e Sais Biliares/metabolismo , Linhagem Celular , Quimiocina CCL5/metabolismo , Colesterol/metabolismo , Dependovirus/metabolismo , Feminino , Glicina/metabolismo , Homeostase , Humanos , Inflamação/patologia , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , Oxirredução , Estresse Oxidativo , Superóxidos/metabolismo , Transaminases/deficiência , Transaminases/metabolismo
6.
Redox Biol ; 43: 101982, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34020311

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is involved in a global outbreak affecting millions of people who manifest a variety of symptoms. Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 is increasingly associated with cardiovascular complications requiring hospitalizations; however, the mechanisms underlying these complications remain unknown. Nitric oxide (NO) and hydrogen sulfide (H2S) are gasotransmitters that regulate key cardiovascular functions. METHODS: Blood samples were obtained from 68 COVID-19 patients and 33 controls and NO and H2S metabolites were assessed. H2S and NO levels were compared between cases and controls in the entire study population and subgroups based on race. The availability of gasotransmitters was examined based on severity and outcome of COVID-19 infection. The performance of H2S and NO levels in predicting COVID-19 infection was also analyzed. Multivariable regression analysis was performed to identify the effects of traditional determinants of gasotransmitters on NO and H2S levels in the patients with COVID-19 infection. RESULTS: Significantly reduced NO and H2S levels were observed in both Caucasian and African American COVID-19 patients compared to healthy controls. COVID-19 patients who died had significantly higher NO and H2S levels compared to COVID-19 patients who survived. Receiver-operating characteristic analysis of NO and H2S metabolites in the study population showed free sulfide levels to be highly predictive of COVID-19 infection based on reduced availability. Traditional determinants of gasotransmitters, namely age, race, sex, diabetes, and hypertension had no effect on NO and H2S levels in COVID-19 patients. CONCLUSION: These observations provide the first insight into the role of NO and H2S in COVID-19 infection, where their low availability may be a result of reduced synthesis secondary to endotheliitis, or increased consumption from scavenging of reactive oxygen species.


Assuntos
COVID-19 , Gasotransmissores , Sulfeto de Hidrogênio , Humanos , Óxido Nítrico , SARS-CoV-2
7.
Blood ; 137(11): 1538-1549, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33512489

RESUMO

Neutrophils play a crucial role in the intertwined processes of thrombosis and inflammation. An altered neutrophil phenotype may contribute to inadequate resolution, which is known to be a major pathophysiological contributor of thromboinflammatory conditions such as sickle cell disease (SCD). The endogenous protein annexin A1 (AnxA1) facilitates inflammation resolution via formyl peptide receptors (FPRs). We sought to comprehensively elucidate the functional significance of targeting the neutrophil-dependent AnxA1/FPR2/ALX pathway in SCD. Administration of AnxA1 mimetic peptide AnxA1Ac2-26 ameliorated cerebral thrombotic responses in Sickle transgenic mice via regulation of the FPR2/ALX (a fundamental receptor involved in resolution) pathway. We found direct evidence that neutrophils with SCD phenotype play a key role in contributing to thromboinflammation. In addition, AnxA1Ac2-26 regulated activated SCD neutrophils through protein kinase B (Akt) and extracellular signal-regulated kinases (ERK1/2) to enable resolution. We present compelling conceptual evidence that targeting the AnxA1/FPR2/ALX pathway may provide new therapeutic possibilities against thromboinflammatory conditions such as SCD.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Anemia Falciforme/metabolismo , Anexina A1/metabolismo , Receptores de Formil Peptídeo/metabolismo , Receptores de Lipoxinas/metabolismo , Transdução de Sinais , Trombose/metabolismo , Adulto , Anemia Falciforme/complicações , Anemia Falciforme/patologia , Animais , Feminino , Humanos , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Neutrófilos/patologia , Trombose/etiologia , Trombose/patologia , Adulto Jovem
9.
Cell Death Differ ; 28(2): 780-798, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32968199

RESUMO

ATP-binding cassette transporters A1 (ABCA1) and G1 (ABCG1) play a vital role in promoting cholesterol efflux. Although, the dysregulation of these transporters was attributed as one of the mechanisms of atherogenesis, what renders their dysfunction is not well explored. Previously, we have reported that thrombin without having any effect on ABCG1 levels depletes ABCA1 levels affecting cholesterol efflux. In this study, we explored the mechanisms underlying thrombin-induced depletion of ABCA1 levels both in macrophages and smooth muscle cells. Under normal physiological conditions, COP9 signalosome subunit 3 (CSN3) was found to exist in complex with ABCA1 and in the presence of proatherogenic stimulants such as thrombin, ABCA1 was phosphorylated and dissociated from CSN3, leading to its degradation. Forced expression of CSN3 inhibited thrombin-induced ABCA1 ubiquitination and degradation, restored cholesterol efflux and suppressed foam cell formation. In Western diet (WD)-fed ApoE-/- mice, CSN3 was also disassociated from ABCA1 otherwise remained as a complex in Chow diet (CD)-fed ApoE-/- mice. Interestingly, depletion of CSN3 levels in WD-fed ApoE-/- mice significantly lowered ABCA1 levels, inhibited cholesterol efflux and intensified foam cell formation exacerbating the lipid laden atherosclerotic plaque formation. Mechanistic studies have revealed the involvement of Par1-Gα12-Pyk2-Gab1-PKCθ signaling in triggering phosphorylation of ABCA1 and its disassociation from CSN3 curtailing cholesterol efflux and amplifying foam cell formation. In addition, although both CSN3 and ABCA1 were found to be colocalized in human non-lesion coronary arteries, their levels were decreased as well as dissociated from each other in advanced atherosclerotic lesions. Together, these observations reveal for the first time an anti-atherogenic role of CSN3 and hence, designing therapeutic drugs protecting its interactions with ABCA1 could be beneficial against atherosclerosis.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/metabolismo , Apolipoproteínas E/fisiologia , Aterosclerose/patologia , Complexo do Signalossomo COP9/metabolismo , Macrófagos Peritoneais/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptor PAR-1/fisiologia , Transportador 1 de Cassete de Ligação de ATP/genética , Animais , Aterosclerose/etiologia , Aterosclerose/metabolismo , Complexo do Signalossomo COP9/genética , Colesterol/metabolismo , Dieta Ocidental/efeitos adversos , Feminino , Células Espumosas/metabolismo , Células Espumosas/patologia , Humanos , Macrófagos Peritoneais/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Proteínas Proto-Oncogênicas/genética , Células RAW 264.7 , Transdução de Sinais , Trombina/metabolismo
10.
Angiogenesis ; 24(1): 177-190, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33113074

RESUMO

Integrin activation contributes to key blood cell functions including adhesion, proliferation and migration. An essential step in the cell signaling pathway that activates integrin requires the binding of talin to the ß-integrin cytoplasmic tail. Whereas this pathway is understood in platelets in detail, considerably less is known regarding how integrin-mediated adhesion in endothelium contributes to postnatal angiogenesis. We utilized an inducible EC-specific talin1 knock-out mouse (Tln1 EC-KO) and talin1 L325R knock-in mutant (Tln1 L325R) mouse, in which talin selectively lacks the capacity to activate integrins, to assess the role of integrin activation during angiogenesis. Deletion of talin1 during postnatal days 1-3 (P1-P3) caused lethality by P8 with extensive defects in retinal angiogenesis and widespread hemorrhaging. Tln1 EC-KO mice displayed reduced retinal vascular area, impaired EC sprouting and proliferation relative to Tln1 CTRLs. In contrast, induction of talin1 L325R in neonatal mice resulted in modest defects in retinal angiogenesis and mice survived to adulthood. Interestingly, deletion of talin1 or expression of talin1 L325R in ECs increased MAPK/ERK signaling. Strikingly, B16-F0 tumors grown in Tln1 L325R adult mice were 55% smaller and significantly less vascularized than tumors grown in littermate controls. EC talin1 is indispensable for postnatal development angiogenesis. The role of EC integrin activation appears context-dependent as its inhibition is compatible with postnatal development with mild defects in retinal angiogenesis but results in marked defects in tumor growth and angiogenesis. Inhibiting EC pan-integrin activation may be an effective approach to selectively target tumor blood vessel growth.


Assuntos
Células Endoteliais/citologia , Integrinas/metabolismo , Neovascularização Fisiológica , Talina/metabolismo , Animais , Animais Recém-Nascidos , Proliferação de Células , Células Endoteliais/metabolismo , Sistema de Sinalização das MAP Quinases , Camundongos Knockout , Mutação/genética , Neoplasias/irrigação sanguínea , Neoplasias/patologia , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Retina/fisiologia , Talina/genética
11.
Matrix Biol ; 96: 87-103, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33157226

RESUMO

While vital to platelet and leukocyte adhesion, the role of integrin affinity modulation in adherent cells remains controversial. In endothelial cells, atheroprone hemodynamics and oxidized lipoproteins drive an increase in the high affinity conformation of α5ß1 integrins in endothelial cells in vitro, and α5ß1 integrin inhibitors reduce proinflammatory endothelial activation to these stimuli in vitro and in vivo. However, the importance of α5ß1 integrin affinity modulation to endothelial phenotype remains unknown. We now show that endothelial cells (talin1 L325R) unable to induce high affinity integrins initially adhere and spread but show significant defects in nascent adhesion formation. In contrast, overall focal adhesion number, area, and composition in stably adherent cells are similar between talin1 wildtype and talin1 L325R endothelial cells. However, talin1 L325R endothelial cells fail to induce high affinity α5ß1 integrins, fibronectin deposition, and proinflammatory responses to atheroprone hemodynamics and oxidized lipoproteins. Inducing the high affinity conformation of α5ß1 integrins in talin1 L325R endothelial cells suggest that NF-κB activation and maximal fibronectin deposition require both integrin activation and other integrin-independent signaling. In endothelial-specific talin1 L325R mice, atheroprone hemodynamics fail to promote inflammation and macrophage recruitment, demonstrating a vital role for integrin activation in regulating endothelial phenotype.


Assuntos
Aterosclerose/metabolismo , Células Endoteliais/citologia , Integrina alfa5beta1/metabolismo , Talina/genética , Animais , Aterosclerose/genética , Adesão Celular , Células Cultivadas , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Fibronectinas/metabolismo , Adesões Focais/metabolismo , Humanos , Integrina alfa5beta1/química , Camundongos , Mutação , NF-kappa B/metabolismo , Conformação Proteica , Transdução de Sinais
12.
Redox Biol ; 38: 101817, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33310503

RESUMO

Oxidative stress drives the pathogenesis of atrial fibrillation (AF), the most common arrhythmia. In the cardiovascular system, cystathionine γ-lyase (CSE) serves as the primary enzyme producing hydrogen sulfide (H2S), a mammalian gasotransmitter that reduces oxidative stress. Using a case control study design in patients with and without AF and a mouse model of CSE knockout (CSE-KO), we evaluated the role of H2S in the etiology of AF. Patients with AF (n = 51) had significantly reduced plasma acid labile sulfide levels compared to patients without AF (n = 65). In addition, patients with persistent AF (n = 25) showed lower plasma free sulfide levels compared to patients with paroxysmal AF (n = 26). Consistent with an important role for H2S in AF, CSE-KO mice had decreased atrial sulfide levels, increased atrial superoxide levels, and enhanced propensity for induced persistent AF compared to wild type (WT) mice. Rescuing H2S signaling in CSE-KO mice by Diallyl trisulfide (DATS) supplementation or reconstitution with endothelial cell specific CSE over-expression significantly reduced atrial superoxide, increased sulfide levels, and lowered AF inducibility. Lastly, low H2S levels in CSE KO mice was associated with atrial electrical remodeling including longer effective refractory periods, slower conduction velocity, increased myocyte calcium sparks, and increased myocyte action potential duration that were reversed by DATS supplementation or endothelial CSE overexpression. Our findings demonstrate an important role of CSE and H2S bioavailability in regulating electrical remodeling and susceptibility to AF.


Assuntos
Fibrilação Atrial , Remodelamento Atrial , Sulfeto de Hidrogênio , Animais , Disponibilidade Biológica , Estudos de Casos e Controles , Endotélio Vascular , Humanos , Camundongos , Camundongos Knockout
13.
Methods Mol Biol ; 2217: 17-25, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33215373

RESUMO

Integrin activation is a crucial event for multiple biological functions. Therefore, methods to detect integrin activation are vital. Since the main cellular function of integrins is adhesion, we and others utilize this feature to measure integrin activation. Here, we describe how to detect the activity of the fibronectin-binding integrin α5ß1 using a fusion of glutathione S-transferase (GST) to the 9th, 10th, and 11th type III repeats on fibronectin (GST-FNIII9-11). Moreover, we detail how to measure αvß3 integrin activity using the ligand-mimetic WOW-1 antibody that selectively binds unoccupied αvß3 integrins. Finally, we describe methods of testing ligation of fibronectin-binding integrins utilizing monoclonal antibodies against ligand-induced binding sites (LIBS).


Assuntos
Anticorpos/metabolismo , Fibronectinas/genética , Immunoblotting/métodos , Integrina alfa5beta1/genética , Peptídeos/genética , Proteínas Recombinantes de Fusão/genética , Anticorpos/química , Sítios de Ligação , Adesão Celular , Linhagem Celular , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Fibronectinas/metabolismo , Fibronectinas/farmacologia , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Humanos , Imuno-Histoquímica/métodos , Integrina alfa5beta1/agonistas , Integrina alfa5beta1/metabolismo , Mimetismo Molecular , Peptídeos/metabolismo , Peptídeos/farmacologia , Ligação Proteica , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Sequências Repetitivas de Aminoácidos
14.
Glob Food Sec ; 26: 100458, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33324539

RESUMO

This article synthesizes recent research by ICRISAT and its partners to analyse the business case for sorghum and millets in ESA and the wider strategy of commercialization on which this is based. The business case is stronger for sorghum because of its greater impact on poverty and food security, but millets are better suited to a strategy of commercialization. Commercial demand for millets is primarily driven by specialty markets for flour while that for sorghum is limited to beer. Demand for improved varieties is driven primarily by the need for early - maturity that shortens the hungry period. Future growth in production depends on increased opportunities for inter-regional trade.

15.
J Am Heart Assoc ; 9(23): e017195, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33208022

RESUMO

Background The mutated α-B-Crystallin (CryABR120G) mouse model of desmin-related myopathy (DRM) shows an age-dependent onset of pathologic cardiac remodeling and progression of heart failure. CryABR120G expression in cardiomyocytes affects the mitochondrial spatial organization within the myofibrils, but the molecular perturbation within the mitochondria in the relation of the overall course of the proteotoxic disease remains unclear. Methods and Results CryABR120G mice show an accumulation of electron-dense aggregates and myofibrillar degeneration associated with the development of cardiac dysfunction. Though extensive studies demonstrated that these altered ultrastructural changes cause cardiac contractility impairment, the molecular mechanism of cardiomyocyte death remains elusive. Here, we explore early pathological processes within the mitochondria contributing to the contractile dysfunction and determine the pathogenic basis for the heart failure observed in the CryABR120G mice. In the present study, we report that the CryABR120G mice transgenic hearts undergo altered mitochondrial dynamics associated with increased level of dynamin-related protein 1 and decreased level of optic atrophy type 1 as well as mitofusin 1 over the disease process. In association with these changes, an altered level of the components of mitochondrial oxidative phosphorylation and pyruvate dehydrogenase complex regulatory proteins occurs before the manifestation of pathologic adverse remodeling in the CryABR120G hearts. Mitochondria isolated from CryABR120G transgenic hearts without visible pathology show decreased electron transport chain complex activities and mitochondrial respiration. Taken together, we demonstrated the involvement of mitochondria in the pathologic remodeling and progression of DRM-associated cellular dysfunction. Conclusions Mitochondrial dysfunction in the form of altered mitochondrial dynamics, oxidative phosphorylation and pyruvate dehydrogenase complex proteins level, abnormal electron transport chain complex activities, and mitochondrial respiration are evident on the CryABR120G hearts before the onset of detectable pathologies and development of cardiac contractile dysfunction.


Assuntos
Cardiomiopatias/etiologia , Cardiomiopatias/patologia , Dinâmica Mitocondrial/fisiologia , Fosforilação Oxidativa , Animais , Cardiomiopatias/metabolismo , Desmina , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Cadeia B de alfa-Cristalina
16.
Commun Biol ; 3(1): 682, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33203971

RESUMO

Methamphetamine-associated cardiomyopathy is the leading cause of death linked with illicit drug use. Here we show that Sigmar1 is a therapeutic target for methamphetamine-associated cardiomyopathy and defined the molecular mechanisms using autopsy samples of human hearts, and a mouse model of "binge and crash" methamphetamine administration. Sigmar1 expression is significantly decreased in the hearts of human methamphetamine users and those of "binge and crash" methamphetamine-treated mice. The hearts of methamphetamine users also show signs of cardiomyopathy, including cellular injury, fibrosis, and enlargement of the heart. In addition, mice expose to "binge and crash" methamphetamine develop cardiac hypertrophy, fibrotic remodeling, and mitochondrial dysfunction leading to contractile dysfunction. Methamphetamine treatment inhibits Sigmar1, resulting in inactivation of the cAMP response element-binding protein (CREB), decreased expression of mitochondrial fission 1 protein (FIS1), and ultimately alteration of mitochondrial dynamics and function. Therefore, Sigmar1 is a viable therapeutic agent for protection against methamphetamine-associated cardiomyopathy.


Assuntos
Cardiomiopatias/induzido quimicamente , Metanfetamina/toxicidade , Mitocôndrias/efeitos dos fármacos , Receptores sigma/metabolismo , Animais , Cardiomiopatias/prevenção & controle , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Esquema de Medicação , Regulação da Expressão Gênica/efeitos dos fármacos , Coração/efeitos dos fármacos , Humanos , Metanfetamina/administração & dosagem , Camundongos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Receptores sigma/genética
17.
Zootaxa ; 4849(1): zootaxa.4849.1.1, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-33056748

RESUMO

A checklist of the dragonflies and damselflies occurring in Bangladesh, Bhutan, India (including Andaman and Nicobar Islands), Nepal, Pakistan and Sri Lanka is presented. In total 588 (including 559 full species) taxa are known to occur in the region of which 251 taxa (species subspecies) are single country endemics. Recent taxonomic changes relevant to the area are summarized. Sixteen taxa are synonymized and a checklist of all synonyms established since 1950 is provided. Information is given on available larval descriptions including a list of genera present in the region for which no larvae have yet been described. Numerous species occurring in the area are still poorly known and a list of genera for which a revision is urgently needed is provided.                The following new synonyms are established: Calicnemia sudhaae Mitra, 1994 = Calicnemia imitans Lieftinck, 1948 syn. nov.; Ceriagrion fallax cerinomelas Lieftinck, 1927 = Ceriagrion fallax Ris, 1914 syn. nov.; Ceriagrion fallax pendleburyi Laidlaw, 1931 = Ceriagrion fallax Ris, 1914 syn. nov.; Coenagrion kashmirus Chowdhary Das, 1975 = Ischnura forcipata Morton, 1907 syn. nov.; Enallagma insula Fraser, 1920 = Aciagrion occidentale Laidlaw, 1919 syn. nov.; Himalagrion pithoragarhicum Sahni, 1964 = Ceriagrion fallax Ris, 1914 syn. nov.; Ischnura bhimtalensis Sahni, 1965 = Ischnura rubilio Selys, 1876 syn. nov.; Onychargia indica Sahni, 1964 = Paracercion calamorum (Ris, 1916) syn. nov.; Anaciaeschna kashmirense Singh Baijal, 1954 = Anaciaeschna martini (Selys, 1897) syn. nov.; Cyclogomphus vesiculosus Selys, 1854 = Cyclogomphus ypsilon Selys, 1954 syn. nov.; Chlorogomphus brittoi Navás, 1934 = Chlorogomphus xanthoptera (Fraser, 1919) syn. nov.; Hylaeothemis indica Fraser, 1946 = Hylaeothemis apicalis Fraser, 1924 syn. nov.; Sympetrum durum Bartenef, 1916 = Sympetrum striolatum commixtum Selys, 1884 syn. nov.; Sympetrum himalayanum Navás, 1934 = Sympetrum hypomelas (Selys, 1884) syn. nov.; Sympetrum haematoneura Fraser, 1924 = Sympetrum speciosum Oguma, 1915 syn. nov.; Sympetrum speciosum taiwanum Asahina, 1951 = Sympetrum speciosum Oguma, 1915 syn. nov.                In addition, Periaeschna lebasi Navás, 1930 is regarded a nomen nudum. The following new combinations are proposed: Onychogomphus acinaces Laidlaw, 1922 is transferred to the genus Melligomphus Chao, 1990 resulting in Melligomphus acinaces (Laidlaw, 1922) comb. nov. Onychogomphus saundersii Selys, 1854 is transferred to the genus Nychogomphus Carle, 1986 resulting in Nychogomphus saundersii (Selys, 1854) comb. nov..


Assuntos
Odonatos , Animais , Bangladesh , Butão , Índia , Insetos , Nepal , Paquistão , Sri Lanka
19.
J Am Heart Assoc ; 9(11): e016099, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32468886

RESUMO

Background Alteration in hemodynamic shear stress at atheroprone sites promotes endothelial paracellular pore formation and permeability. The molecular mechanism remains unknown. Methods and Results We show that Nck (noncatalytic region of tyrosine kinase) deletion significantly ameliorates disturbed flow-induced permeability, and selective isoform depletion suggests distinct signaling mechanisms. Only Nck1 deletion significantly reduces disturbed flow-induced paracellular pore formation and permeability, whereas Nck2 depletion has no significant effects. Additionally, Nck1 re-expression, but not Nck2, restores disturbed flow-induced permeability in Nck1/2 knockout cells, confirming the noncompensating roles. In vivo, using the partial carotid ligation model of disturbed flow, Nck1 knockout prevented the increase in vascular permeability, as assessed by Evans blue and fluorescein isothiocyanate dextran extravasations and leakage of plasma fibrinogen into the vessel wall. Domain swap experiments mixing SH2 (phosphotyrosine binding) and SH3 (proline-rich binding) domains between Nck1 and Nck2 showed a dispensable role for SH2 domains but a critical role for the Nck1 SH3 domains in rescuing disturbed flow-induced endothelial permeability. Consistent with this, both Nck1 and Nck2 bind to platelet endothelial adhesion molecule-1 (SH2 dependent) in response to shear stress, but only Nck1 ablation interferes with shear stress-induced PAK2 (p21-activated kinase) membrane translocation and activation. A single point mutation into individual Nck1 SH3 domains suggests a role for the first domain of Nck1 in PAK recruitment to platelet endothelial cell adhesion molecule-1 and activation in response to shear stress. Conclusions This work provides the first evidence that Nck1 but not the highly similar Nck2 plays a distinct role in disturbed flow-induced vascular permeability by selective p21-activated kinase activation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Doenças das Artérias Carótidas/enzimologia , Células Endoteliais/enzimologia , Mecanotransdução Celular , Proteínas Oncogênicas/metabolismo , Quinases Ativadas por p21/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Doenças das Artérias Carótidas/patologia , Doenças das Artérias Carótidas/fisiopatologia , Células Cultivadas , Modelos Animais de Doenças , Células Endoteliais/patologia , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Proteínas Oncogênicas/genética , Permeabilidade , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Fluxo Sanguíneo Regional , Estresse Mecânico , Quinases Ativadas por p21/genética , Domínios de Homologia de src
20.
J Clin Invest ; 130(8): 4331-4347, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32427580

RESUMO

Although the Canakinumab Anti-Inflammatory Thrombosis Outcomes Study (CANTOS) established the role of treating inflammation in atherosclerosis, our understanding of endothelial activation at atherosclerosis-prone sites remains limited. Disturbed flow at atheroprone regions primes plaque inflammation by enhancing endothelial NF-κB signaling. Herein, we demonstrate a role for the Nck adaptor proteins in disturbed flow-induced endothelial activation. Although highly similar, only Nck1 deletion, but not Nck2 deletion, limited flow-induced NF-κB activation and proinflammatory gene expression. Nck1-knockout mice showed reduced endothelial activation and inflammation in both models, disturbed flow- and high fat diet-induced atherosclerosis, whereas Nck2 deletion did not. Bone marrow chimeras confirmed that vascular Nck1, but not hematopoietic Nck1, mediated this effect. Domain-swap experiments and point mutations identified the Nck1 SH2 domain and the first SH3 domain as critical for flow-induced endothelial activation. We further characterized Nck1's proinflammatory role by identifying interleukin 1 type I receptor kinase-1 (IRAK-1) as a Nck1-selective binding partner, demonstrating that IRAK-1 activation by disturbed flow required Nck1 in vitro and in vivo, showing endothelial Nck1 and IRAK-1 staining in early human atherosclerosis, and demonstrating that disturbed flow-induced endothelial activation required IRAK-1. Taken together, our data reveal a hitherto unknown link between Nck1 and IRAK-1 in atherogenic inflammation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Aterosclerose/metabolismo , Proteínas Oncogênicas/metabolismo , Placa Aterosclerótica/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Aterosclerose/genética , Aterosclerose/patologia , Linhagem Celular , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Quinases Associadas a Receptores de Interleucina-1/genética , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Camundongos , Camundongos Knockout , Proteínas Oncogênicas/genética , Placa Aterosclerótica/genética , Placa Aterosclerótica/patologia , Mutação Puntual , Domínios de Homologia de src
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