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1.
J Proteome Res ; 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39412830

RESUMO

The distinction between noncancerous and cancerous breast tissues is challenging in clinical settings, and discovering new proteomics-based biomarkers remains underexplored. Through a pilot proteomic study (discovery cohort), we aimed to identify a protein signature indicative of breast cancer for subsequent validation using six published proteomics/transcriptomics data sets (validation cohorts). Sequential window acquisition of all theoretical (SWATH)-based mass spectrometry revealed 370 differentially abundant proteins between noncancerous tissue and breast cancer. Protein-protein interaction-based networks and enrichment analyses revealed dysregulation in pathways associated with extracellular matrix organization, platelet degranulation, the innate immune system, and RNA metabolism in breast cancer. Through multivariate unsupervised analysis, we identified a four-protein signature (OGN, LUM, DCN, and COL14A1) capable of distinguishing breast cancer. This dysregulation pattern was consistently verified across diverse proteomics and transcriptomics data sets. Dysregulation magnitude was notably higher in poor-prognosis breast cancer subtypes like Basal-Like and HER2 compared to Luminal A. Diagnostic evaluation (receiver operating characteristic (ROC) curves) of the signature in distinguishing breast cancer from noncancerous tissue revealed area under the curve (AUC) ranging from 0.87 to 0.9 with predictive accuracy of 80% to 82%. Upon stratifying, to solely include the Basal-Like/Triple-Negative subtype, the ROC AUC increased to 0.922-0.959 with predictive accuracy of 84.2%-89%. These findings suggest a potential role for the identified signature in distinguishing cancerous from noncancerous breast tissue, offering insights into enhancing diagnostic accuracy.

2.
Int J Mol Sci ; 25(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38612763

RESUMO

Idiopathic intellectual disability (IID) encompasses the cases of intellectual disability (ID) without a known cause and represents approximately 50% of all cases. Neural progenitor cells (NPCs) from the olfactory neuroepithelium (NEO) contain the same information as the cells found in the brain, but they are more accessible. Some miRNAs have been identified and associated with ID of known etiology. However, in idiopathic ID, the effect of miRNAs is poorly understood. The aim of this study was to determine the miRNAs regulating the expression of mRNAs that may be involved in development of IID. Expression profiles were obtained using NPC-NEO cells from IID patients and healthy controls by microarray. A total of 796 miRNAs and 28,869 mRNAs were analyzed. Several miRNAs were overexpressed in the IID patients compared to controls. miR-25 had the greatest expression. In silico analysis showed that ROBO2 was the target for miR-25, with the highest specificity and being the most down-regulated. In vitro assay showed an increase of miR-25 expression induced a decrease in ROBO2 expression. In neurodevelopment, ROBO2 plays a crucial role in episodic learning and memory, so its down-regulation, caused by miR-25, could have a fundamental role in the intellectual disability that, until now, has been considered idiopathic.


Assuntos
Deficiência Intelectual , MicroRNAs , Humanos , Deficiência Intelectual/genética , MicroRNAs/genética , Encéfalo , Regulação para Baixo/genética , Aprendizagem , RNA Mensageiro , Proteínas Roundabout , Receptores Imunológicos/genética
3.
Int J Mol Sci ; 24(15)2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37569780

RESUMO

Breast cancer treatments are limited by the cancer subtype and its selectivity towards tumor cells, hence the importance of finding compounds that increase the survival of healthy cells and target any subtype. Incomptine A (IA) is a sesquiterpene lactone with demonstrated cytotoxic activity. In this study, through in vitro assays, it was observed that IA has similar cytotoxic activity between the subtypes triple negative, HER2+, and luminal A of the breast cancer cell lines. IA cytotoxic activity is higher in cancer than in nontumorigenic cells, and its selectivity index for cancer cells is more than that of the drug doxorubicin. Molecular docking and its in silico comparison with the 2-Deoxyglucose inhibitor suggest that IA could bind to Hexokinase II (HKII), decreasing its expression. Since we did not find changes in the expression of the glycolytic pathway, we suppose that IA could affect the antiapoptotic function of HKII in cancer cells. The IA-HKII union would activate the voltage-gated anion channel 1 (VDAC1), resuming apoptosis. Therefore, we suggest that IA could be used against almost any subtype and that its cytotoxic effect could be due to the reactivation of apoptosis in breast cancer cells.

4.
Muscle Nerve ; 63(2): 239-249, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33125736

RESUMO

INTRODUCTION: We conducted an open-label study to examine the effects of the flavonoid (-)-epicatechin in seven ambulatory adult patients with Becker muscular dystrophy (BMD). METHODS: Seven participants received (-)-epicatechin 50 mg twice per day for 8 weeks. Pre- and postprocedures included biceps brachii biopsy to assess muscle structure and growth-relevant endpoints by western blotting, mitochondria volume measurement, and cristae abundance by electron microscopy, graded exercise testing, and muscle strength and function tests. RESULTS: Western blotting showed significantly increased levels of enzymes modulating cellular bioenergetics (liver kinase B1 and 5'-adenosine monophosphate-activated protein kinase). Peroxisome proliferator-activated receptor gamma coactivator-1alpha, a transcriptional coactivator of genes involved in mitochondrial biogenesis and cristae-associated mitofilin levels, increased as did cristae abundance. Muscle and plasma follistatin increased significantly while myostatin decreased. Markers of skeletal muscle regeneration myogenin, myogenic regulatory factor-5, myoblast determination protein 1, myocyte enhancer factor-2, and structure-associated proteins, including dysferlin, utrophin, and intracellular creatine kinase, also increased. Exercise testing demonstrated decreased heart rate, maximal oxygen consumption per kilogram, and plasma lactate levels at defined workloads. Tissue saturation index improved in resting and postexercise states. DISCUSSION: (-)-Epicatechin, an exercise mimetic, appears to have short-term positive effects on tissue biomarkers indicative of mitochondrial biogenesis and muscle regeneration, and produced improvements in graded exercise testing parameters in patients with BMD.


Assuntos
Catequina/uso terapêutico , Músculo Esquelético/metabolismo , Distrofia Muscular de Duchenne/tratamento farmacológico , Adulto , Biópsia , Western Blotting , Creatina Quinase/metabolismo , Disferlina/metabolismo , Teste de Esforço , Folistatina/metabolismo , Frequência Cardíaca , Humanos , Ácido Láctico/sangue , Fatores de Transcrição MEF2/metabolismo , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Mitocôndrias/ultraestrutura , Proteínas Mitocondriais/metabolismo , Tamanho Mitocondrial , Proteínas Musculares/metabolismo , Força Muscular , Músculo Esquelético/fisiopatologia , Músculo Esquelético/ultraestrutura , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/patologia , Distrofia Muscular de Duchenne/fisiopatologia , Proteína MyoD/metabolismo , Fator Regulador Miogênico 5/metabolismo , Miogenina/metabolismo , Miostatina/metabolismo , Biogênese de Organelas , Consumo de Oxigênio , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Regeneração , Utrofina/metabolismo
5.
Pharmacol Res ; 151: 104540, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31722227

RESUMO

Currently, there is great interest in identifying endogenous (i.e. physiological) stimulators of mitochondrial biogenesis (MB), in particular, those that may mediate the effects of exercise. The molecular size of the cacao flavanols (epicatechin and catechin) highly resembles that of sterols and epicatechin has been reported to activate cells surface receptors leading to the stimulation of MB in endothelial and skeletal muscle cells translating into enhanced exercise capacity. We therefore hypothesize, that epicatechin may be acting as a structural mimic of an as yet unknown sterol capable of stimulating MB. We developed a new synthetic process for obtaining enantiomerically pure preparations of (-)-epicatechin and (+)-epicatechin. Applying spatial analytics and molecular modeling, we found that the two isoforms of epicatechin, (-) and (+), have a structural resemblance to 11-ß-hydroxypregnenolone, a sterol with no previously described biological activity. As reported in this proof-of-concept study performed in primary cultures of endothelial and muscle cells, 11-ß-hydroxypregnenolone is one of the most potent inducers of MB as significant activity can be detected at femtomolar levels. The relative potency of (-)/(+)-epicatechin isoforms and on inducing MB correlates with their degree of spatial homology towards the 11-ß-hydroxypregnenolone. On the basis of these results, the detailed in vivo characterization of the potential for these sterols to act as endogenous modulators of MB is warranted.


Assuntos
Catequina/química , Catequina/farmacologia , Mimetismo Molecular , Biogênese de Organelas , Esteróis/química , Esteróis/farmacologia , Animais , Bovinos , Linhagem Celular , Células Cultivadas , Camundongos , Modelos Moleculares , Estereoisomerismo
6.
J Physiol ; 597(7): 1805-1817, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30681142

RESUMO

KEY POINTS: Heart failure with preserved ejection fraction (HFpEF) is seen more frequently in older women; risk factors include age, hypertension and excess weight. No female animal models of early stage remodelling (pre-HFpEF) have examined the effects that the convergence of such factors have on cardiac structure and function. In this study, we demonstrate that ageing can lead to the development of mild chamber remodelling, diffuse fibrosis and loss of diastolic function. The loss of oestrogens further aggravates such changes by leading to a notable drop in cardiac output (while preserving normal ejection fraction) in the presence of diffuse fibrosis that is more predominant in endocardium and is accompanied by papillary fibrosis. Excess weight did not markedly aggravate such findings. This animal model recapitulates many of the features recognized in older, female HFpEF patients and thus, may serve to examine the effects of candidate therapeutic agents. ABSTRACT: Two-thirds of patients with heart failure with preserved ejection fraction (HFpEF) are older women, and risk factors include hypertension and excess weight/obesity. Pathophysiological factors that drive early disease development (before heart failure ensues) remain obscure and female animal models are lacking. The study evaluated the intersecting roles of ageing, oestrogen depletion and excess weight on altering cardiac structure/function. Female, 18-month-old, Fischer F344 rats were divided into an aged group, aged + ovariectomy (OVX) and aged + ovariectomy + 10% fructose (OVF) in drinking water (n = 8-16/group) to induce weight gain. Left ventricular (LV) structure/function was monitored by echocardiography. At 22 months of age, animals were anaesthetized and catheter-based haemodynamics evaluated, followed by histological measures of chamber morphometry and collagen density. All aged animals developed hypertension. OVF animals increased body weight. Echocardiography only detected mild chamber remodelling with ageing while intraventricular pressure-volume loop analysis showed significant (P < 0.05) decreases vs. ageing in stroke volume (13% OVX and 15% for OVF), stroke work (34% and 52%) and cardiac output (29% and 27%), and increases in relaxation time (10% OVX) with preserved ejection fraction. Histology indicated papillary and interstitial fibrosis with ageing, which was higher in the endocardium of OVX and OVF groups. With ageing, ovariectomy leads to the loss of diastolic and global LV function while preserving ejection fraction. This model recapitulates many cardiovascular features present in HFpEF patients and may help understand the roles that ageing and oestrogen depletion play in early (pre-HFpEF) disease development.


Assuntos
Estrogênios/metabolismo , Fibrose/patologia , Ventrículos do Coração/anatomia & histologia , Função Ventricular/fisiologia , Remodelação Ventricular/fisiologia , Envelhecimento , Animais , Colágeno/metabolismo , Ecocardiografia , Feminino , Cardiopatias , Ventrículos do Coração/patologia , Hemodinâmica , Ovariectomia , Ratos , Ratos Endogâmicos F344
7.
Am J Physiol Regul Integr Comp Physiol ; 317(1): R160-R168, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31091156

RESUMO

Sepsis is a major clinical challenge, with therapy limited to supportive interventions. Therefore, the search for novel remedial approaches is of great importance. We addressed whether hyperbaric oxygen therapy (HBOT) could improve the outcome of sepsis using an acute experimental mouse model. Sepsis was induced in male CD-1 mice by cecal ligation and puncture (CLP) tailored to result in 80-90% mortality within 72 h of the insult. After CLP, mice were randomized into two groups receiving HBOT or not at different times after the initial insult or subjected to multiple HBOT treatments. HBOT conditions were 98% oxygen pressurized to 2.4 atmospheres for 1 h. HBOT within 1 h after CLP resulted in 52% survival in comparison with mice that did not receive the treatment (13% survival). Multiple HBOT at 1 and 6 h or 1, 6, and 21 h displayed an increase in survival of >50%, but they were not significantly different from a single treatment after 1 h of CLP. Treatments at 6 or 21 h after CLP, excluding the 1 h of treatment, did not show any protective effect. Early HBO treatment did not modify bacterial counts after CLP, but it was associated with decreased expression of TNF-α, IL-6, and IL-10 expression in the liver within 3 h after CLP. The decrease of cytokine expression was reproduced in cultured macrophages after exposure to HBOT. Early HBOT could be of benefit in the treatment of sepsis, and the protective mechanism may be related to a reduction in the systemic inflammatory response.


Assuntos
Modelos Animais de Doenças , Oxigenoterapia Hiperbárica , Sepse/terapia , Animais , Ceco/lesões , Citocinas/genética , Citocinas/metabolismo , Regulação da Expressão Gênica , Ligadura , Lipopolissacarídeos/toxicidade , Macrófagos/metabolismo , Masculino , Camundongos , Mitocôndrias/metabolismo , Consumo de Oxigênio , Punções
8.
Int J Mol Sci ; 20(21)2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31689918

RESUMO

Age-related macular degeneration (AMD) is the leading cause of central vision loss and severe blindness among the elderly population. Recently, we reported on the association of the SGCD gene (encoding for δ-sarcoglycan) polymorphisms with AMD. However, the functional consequence of Sgcd alterations in retinal degeneration is not known. Herein, we characterized changes in the retina of the Sgcd knocked-out mouse (KO, Sgcd-/-). At baseline, we analyzed the retina structure of three-month-old wild-type (WT, Sgcd+/+) and Sgcd-/- mice by hematoxylin and eosin (H&E) staining, assessed the Sgcd-protein complex (α-, ß-, γ-, and ε-sarcoglycan, and sarcospan) by immunofluorescence (IF) and Western blot (WB), and performed electroretinography. Compared to the WT, Sgcd-/- mice are five times more likely to have retinal ruptures. Additionally, all the retinal layers are significantly thinner, more so in the inner plexiform layer (IPL). In addition, the number of nuclei in the KO versus the WT is ever so slightly increased. WT mice express Sgcd-protein partners in specific retinal layers, and as expected, KO mice have decreased or no protein expression, with a significant increase in the α subunit. At three months of age, there were no significant differences in the scotopic electroretinographic responses, regarding both a- and b-waves. According to our data, Sgcd-/- has a phenotype that is compatible with retinal degeneration.


Assuntos
Degeneração Retiniana/genética , Sarcoglicanas/genética , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Retina/metabolismo , Retina/patologia , Sarcoglicanas/metabolismo
9.
Bioorg Med Chem Lett ; 28(4): 658-663, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29395974

RESUMO

To potentially identify proteins that interact (i.e. bind) and may contribute to mediate (-)-epicatechin (Epi) responses in endothelial cells we implemented the following strategy: 1) synthesis of novel Epi derivatives amenable to affinity column use, 2) in silico molecular docking studies of the novel derivatives on G protein-coupled estrogen receptor (GPER), 3) biological assessment of the derivatives on NO production, 4) implementation of an immobilized Epi derivative affinity column and, 5) affinity column based isolation of Epi interacting proteins from endothelial cell protein extracts. For these purposes, the Epi phenol and C3 hydroxyl groups were chemically modified with propargyl or mesyl groups. Docking studies of the novel Epi derivatives on GPER conformers at 14 ns and 70 ns demostrated favorable thermodynamic interactions reaching the binding site. Cultures of bovine coronary artery endothelial cells (BCAEC) treated with Epi derivatives stimulated NO production via Ser1179 phosphorylation of eNOS, effects that were attenuated by the use of the GPER blocker, G15. Epi derivative affinity columns yielded multiple proteins from BCAEC. Proteins were electrophoretically separated and inmmunoblotting analysis revealed GPER as an Epi derivative binding protein. Altogether, these results validate the proposed strategy to potentially isolate and identify novel Epi receptors that may account for its biological activity.


Assuntos
Catequina/análogos & derivados , Catequina/farmacologia , Estrogênios/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Animais , Sítios de Ligação , Catequina/síntese química , Catequina/química , Bovinos , Cromatografia de Afinidade , Vasos Coronários/metabolismo , Células Endoteliais/metabolismo , Estrogênios/síntese química , Estrogênios/química , Simulação de Acoplamento Molecular , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Receptores de Estrogênio/química , Receptores Acoplados a Proteínas G/química , Estereoisomerismo , Relação Estrutura-Atividade
10.
Korean J Physiol Pharmacol ; 21(4): 407-413, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28706454

RESUMO

Vascular reactivity can be influenced by the vascular region, animal age, and pathologies present. Prostaglandins (produced by COX-1 and COX-2) play an important role in the contractile response to phenylephrine in the abdominal aorta of young rats. Although these COXs are found in many tissues, their distribution and role in vascular reactivity are not clear. At a vascular level, they take part in the homeostasis functions involved in many physiological and pathologic processes (e.g., arterial pressure and inflammatory processes). The aim of this study was to analyze changes in the contractile response to phenylephrine of thoracic/abdominal aorta and the coronary artery during aging in rats. Three groups of rats were formed and sacrificed at three distinct ages: prepubescent, young and old adult. The results suggest that there is a higher participation of prostanoids in the contractile effect of phenylephrine in pre-pubescent rats, and a lower participation of the same in old rats. Contrarily, there seems to be a higher participation of prostanoids in the contractile response of the coronary artery of older than pre-pubescent rats. Considering that the changes in the expression of COX-2 were similar for the three age groups and the two tissues tested, and that expression of COX-1 is apparently greater in older rats, COX-1 and COX-2 may lose functionality in relation to their corresponding receptors during aging in rats.

11.
J Food Biochem ; 40(4): 404-410, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27616799

RESUMO

The effects of acute and chronic treatment with Aronia extracts on NO production and endothelial nitric oxide synthase (eNOS) phosphorylation in bovine coronary artery endothelial cells were investigated. Acute time-course and concentration-response experiments were performed to determine the time and concentration at which Aronia induced maximal NO synthesis and eNOS phosphorylation. The findings indicate that relatively low concentrations (0.1 µg/mL) of Aronia extract significantly induced NO synthesis and eNOS phosphorylation after 10 min of treatment. Increased sensitivity of eNOS and a significant increase in NO synthesis resulted from longer-term stimulation with Aronia (48 hr) and an acute re-treatment of the cells (10 min). PRACTICAL APPLICATIONS: These in vitro results may be translated into potential future clinical applications where Aronia extracts may be used for prevention and coadjuvant treatment of cardiovascular diseases via increases in endothelial NO synthesis and related improvements in vascular functions. Given the dose-response effect of Aronia extract in vitro and metabolism of polyphenols that occurs in humans, dose-response studies would be necessary to define the optimal daily amount to be consumed.

12.
Biochim Biophys Acta ; 1838(3): 1047-54, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24060563

RESUMO

The dystrophin-associated protein complex (DAPC) is a multimeric complex that links the extracellular matrix to the actin cytoskeleton, and in some cases dystrophin can be substituted by its autosomal homologue utrophin to form the utrophin-associated protein complex (UAPC). Both complexes maintain the stability of plasma membrane during contraction process and play an important role in transmembrane signaling. Mutations in members of the DAPC are associated with muscular dystrophy and dilated cardiomyopathy. In a previous study with human umbilical cord vessels, we observed that utrophin colocalize with caveolin-1 (Cav-1) which proposed the presence of UAPC in the plasma membrane of vascular smooth muscle (VSM). In the current study, we demonstrated by immunofluorescence analysis, co-immunoprecipitation assays, and subcellular fractionation by sucrose gradients, the existence of an UAPC in lipid raft domains of human umbilical artery smooth muscle cells (HUASMC). This complex is constituted by utrophin, ß-DG, ε-SG, α-smooth muscle actin, Cav-1, endothelial nitric oxide synthase (eNOS) and cavin-1. It was also observed the presence of dystrophin, utrophin Dp71, ß-SG, δ-SG, δ-SG3 and sarcospan in non-lipid raft fractions. Furthermore, the knockdown of α/ß-DG was associated with the decrease in both the synthesis of nitric oxide (NO) and the presence of the phosphorylated (active) form of eNOS; and with a reduction in the downstream activation of some cGMP signaling transduction pathway components. Together these results show the presence of an UAPC complex in HUASMC that may participate in the activity regulation of eNOS and in the vascular function.


Assuntos
Membrana Celular/metabolismo , Distrofina/metabolismo , Microdomínios da Membrana/metabolismo , Músculo Liso Vascular/metabolismo , Artérias Umbilicais/metabolismo , Utrofina/metabolismo , Western Blotting , Proteínas de Transporte/metabolismo , Caveolina 1/metabolismo , Células Cultivadas , GMP Cíclico/metabolismo , Imunofluorescência , Humanos , Imunoprecipitação , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Fosforilação
13.
Pharmacol Res ; 100: 309-20, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26303816

RESUMO

We have provided evidence that the stimulatory effects of (-)-epicatechin ((-)-EPI) on endothelial cell nitric oxide (NO) production may involve the participation of a cell-surface receptor. Thus far, such entity(ies) has not been fully elucidated. The G protein-coupled estrogen receptor (GPER) is a cell-surface receptor that has been linked to protective effects on the cardiovascular system and activation of intracellular signaling pathways (including NO production) similar to those reported with (-)-EPI. In bovine coronary artery endothelial cells (BCAEC) by the use of confocal imaging, we evidence the presence of GPER at the cell-surface and on F-actin filaments. Using in silico studies we document the favorable binding mode between (-)-EPI and GPER. Such binding is comparable to that of the GPER agonist, G1. By the use of selective blockers, we demonstrate that the activation of ERK 1/2 and CaMKII by (-)-EPI is dependent on the GPER/c-SRC/EGFR axis mimicking those effects noted with G1. We also evidence by the use of siRNA the role that GPER has on mediating ERK1/2 activation by (-)-EPI. GPER appears to be coupled to a non Gαi/o or Gαs, protein subtype. To extrapolate our findings to an ex vivo model, we employed phenylephrine pre-contracted aortic rings evidencing that (-)-EPI can mediate vasodilation through GPER activation. In conclusion, we provide evidence that suggests the GPER as a potential mediator of (-)-EPI effects and highlights the important role that GPER may have on cardiovascular system protection.


Assuntos
Catequina/farmacologia , Células Endoteliais/efeitos dos fármacos , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Actinas/metabolismo , Animais , Artérias/efeitos dos fármacos , Artérias/metabolismo , Bovinos , Células Cultivadas , Células Endoteliais/metabolismo , Estrogênios/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Masculino , Óxido Nítrico/metabolismo , Fenilefrina/farmacologia , Ratos , Ratos Wistar , Receptores de Superfície Celular/metabolismo , Transdução de Sinais/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
14.
Am J Physiol Cell Physiol ; 306(9): C794-804, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24553187

RESUMO

Excess enzyme-mediated protein O-GlcNAcylation is known to occur with diabetes mellitus. A characteristic of diabetic cardiomyopathy is the development of myocardial fibrosis. The role that enhanced protein O-GlcNAcylation plays in modulating the phenotype of cardiac fibroblasts (CF) is unknown. To address this issue, rat CF were cultured in normal glucose (NG; 5 mM glucose) or high-glucose (HG; 25 mM) media for 48 h. Results demonstrate that CF cultured in HG have higher levels (~50%) of overall protein O-GlcNAcylation vs. NG cells. Key regulators of collagen synthesis such as transforming-growth factor-ß1 (TGF-ß1), SMADs 2/3, and SMAD 7 protein levels, including those of arginase I and II, were altered, leading to increases in collagen levels. The nuclear transcription factor Sp1 and arginase II evidence excess O-GlcNAcylation in HG cells. Expression in CF of an adenovirus coding for the enzyme N-acetylglucosaminidase, which removes O-GlcNAc moieties from proteins, decreased Sp1 and arginase II O-GlcNAcylation and restored HG-induced perturbations in CF back to NG levels. These findings may have important pathophysiological implications for the development of diabetes-induced cardiac fibrosis.


Assuntos
Colágeno/biossíntese , Cardiomiopatias Diabéticas/metabolismo , Fibroblastos/metabolismo , Glucose/metabolismo , Miocárdio/metabolismo , Processamento de Proteína Pós-Traducional , Acetilglucosaminidase/genética , Acetilglucosaminidase/metabolismo , Animais , Arginase/metabolismo , Células Cultivadas , Cardiomiopatias Diabéticas/patologia , Fibroblastos/patologia , Glicosilação , Masculino , Miocárdio/patologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Proteínas Smad/metabolismo , Fator de Transcrição Sp1/metabolismo , Fatores de Tempo , Transfecção , Fator de Crescimento Transformador beta1/metabolismo , Regulação para Cima
15.
Bioorg Med Chem Lett ; 24(12): 2749-52, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24794111

RESUMO

The consumption of cacao-derived products, particularly in the form of dark chocolate is known to provide beneficial cardiovascular effects in normal individuals and in those with vascular dysfunction (reduced nitric oxide [NO] bioavailability and/or synthesis). Upstream mechanisms by which flavonoids exert these effects are poorly understood and may involve the participation of cell membrane receptors. We previously demonstrated that the flavanol (-)-epicatechin (EPI) stimulates NO production via Ca(+2)-independent eNOS activation/phosphorylation. We wished to investigate the plausible participation of a cell surface receptor using a novel cell-membrane impermeable EPI-Dextran conjugate (EPI-Dx). Under Ca(2+)-free conditions, human coronary artery endothelial cells (HCAEC) were treated for 10min with EPI or EPI-Dx at equimolar concentrations (100nM). Results demonstrate that both EPI and EPI-Dx induced the phosphorylation/activation of PI3K, PDK-1, AKT and eNOS. Interestingly, EPI-Dx effects were significantly higher in magnitude than those of EPI alone. The capacity of EPI-Dx to stimulate cell responses supports the existence of an EPI cell membrane receptor mediating eNOS activation.


Assuntos
Catequina/farmacologia , Membrana Celular/metabolismo , Células Endoteliais/efeitos dos fármacos , Receptores de Superfície Celular/metabolismo , Transdução de Sinais/efeitos dos fármacos , Antioxidantes/farmacologia , Catequina/química , Membrana Celular/efeitos dos fármacos , Dextranos/química , Humanos , Estrutura Molecular , Óxido Nítrico/química , Fosforilação
16.
Physiol Rep ; 12(18): e70064, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39328164

RESUMO

The use of tobacco cigarettes produces locomotor muscle weakness and fatigue intolerance. Also, smokers and chronic obstructive pulmonary disease patients have a greater incidence of muscle injury and a deficient myogenic response. However, the effects of smoke exposure on the recovery from eccentric exercise-induced muscle injuries are unknown. Mice were exposed daily to cigarette smoke (CS) or room air (Air) for 4 months; the anterior crural muscles from one limb were injured by a lengthening contractions protocol (LCP) and recovered for 7 days. Lung compliance was greater, and body weights were lower, in CS-exposed than in the Air group. In LCP-subjected limbs, CS exposure lowered tibialis anterior myofiber cross-sectional area, decreased the size of centrally nucleated myofibers, and decreased extensor digitorum longus (EDL) mass, but did not affect EDL force from both limbs. CS exposure upregulated the mRNA levels of several myogenic (Pax7, Myf5, nNOS) genes in the EDL. The combination of CS exposure and LCP decreased Myf5 and nNOS mRNA levels and exacerbated pro-inflammatory mRNA levels. These data suggest that smoke exposure leads to an excessive pro-inflammatory response in regenerating muscle that is associated with a lower muscle mass recovery from a type of injury that often occurs during strenuous exercise.


Assuntos
Camundongos Endogâmicos C57BL , Contração Muscular , Músculo Esquelético , Animais , Masculino , Camundongos , Músculo Esquelético/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/lesões , Músculo Esquelético/fisiopatologia , Fumaça/efeitos adversos , Fumar Cigarros/efeitos adversos
17.
Food Funct ; 15(7): 3669-3679, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38487922

RESUMO

Sarcopenia is a progressive and generalized age-related skeletal muscle (SkM) disorder characterized by the accelerated loss of muscle mass (atrophy) and function. SkM atrophy is associated with increased incidence of falls, functional decline, frailty and mortality. In its early stage, SkM atrophy is associated with increased pro-inflammatory cytokine levels and proteasome-mediated protein degradation. These processes also link to the activation of atrophy associated factors and signaling pathways for which, there is a lack of approved pharmacotherapies. The objective of this study, was to characterize the capacity of the flavanol (+)-epicatechin (+Epi) to favorably modulate SkM mass and function in a rat model of aging induced sarcopenia and profile candidate mechanisms. Using 23 month old male Sprague-Dawley rats, an 8 weeks oral administration of the +Epi (1 mg per kg per day in water by gavage) was implemented while control rats only received water. SkM strength (grip), treadmill endurance, muscle mass, myofiber area, creatine kinase, lactate dehydrogenase, troponin, α-actin, tumor necrosis factor (TNF)-α and atrophy related endpoints (follistatin, myostatin, NFκB, MuRF 1, atrogin 1) were quantified in plasma and/or gastrocnemius. We also evaluated effects on insulin growth factor (IGF)-1 levels and downstream signaling (AKT/mTORC1). Treatment of aged rats with +Epi, led to significant increases in front paw grip strength, treadmill time and SkM mass vs. controls as well as beneficial changes in makers of myofiber integrity. Treatment significantly reversed adverse changes in plasma and/or SkM TNF-α, IGF-1, atrophy and protein synthesis related endpoints vs. controls. In conclusion, +Epi has the capacity to reverse sarcopenia associated detrimental changes in regulatory pathways leading to improved SkM mass and function. Given these results and its recognized safety and tolerance profile, +Epi warrants consideration for clinical trials.


Assuntos
Catequina , Sarcopenia , Masculino , Ratos , Animais , Sarcopenia/metabolismo , Catequina/farmacologia , Roedores , Ratos Sprague-Dawley , Envelhecimento , Atrofia Muscular/tratamento farmacológico , Atrofia Muscular/metabolismo , Músculo Esquelético/metabolismo , Água/metabolismo
18.
J Med Food ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39321070

RESUMO

Gulf War Illness (GWI) afflicts US military personnel who served in the Persian Gulf War. Suspect causal agents include exposure to pyridostigmine (PB), permethrin (PM) and N,N-diethyl-m-toluamide (DEET). Prominent symptoms include cognitive deficits, such as memory impairment. In aging animal models, we have documented the beneficial effect of the flavanol (-)-epicatechin (Epi) on hippocampus structure and related function. Using a rat model of GWI, we examined the effects of Epi on hippocampus inflammation, oxidative stress, mitochondrial dysfunction, cell death/survival pathways, and memory endpoints. Male Wistar rats underwent 3 weeks of exposure to either vehicles or DEET, PM, PB, and stress. Subgroups of GWI rats were then allocated to receive orally 15 days of either water (vehicle) or 1 mg/kg/day of Epi treatment. Object recognition tasks were performed to assess memory. Hippocampus samples were analyzed. Epi treatment yields significant improvements in short- and long-term memory versus GWI rats. Hippocampus oxidative stress and pro-inflammatory cytokine levels showed significant increases with GWI that were largely normalized with Epi becoming comparable to controls. Significant increases in markers of hippocampus neuroinflammation and cell death were noted with GWI and were also largely reduced with Epi. Neuronal survival signaling pathways were adversely impacted by GWI and were partially or fully restored by Epi. Markers of mitochondrial function were adversely impacted by GWI and were fully restored by Epi. In conclusion, in an animal model of GWI, Epi beneficially impacts recognized markers of hippocampus neuroinflammation, oxidative stress, cell survival, neurotoxicity and mitochondrial function leading to improved memory.

19.
Clin Sci (Lond) ; 125(8): 383-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23642227

RESUMO

HF (heart failure) and T2D (Type 2 diabetes) associate with detrimental alterations in SkM (skeletal muscle) structure/function. We have demonstrated recently that (-)-ERC (epicatechin-rich cocoa) improves SkM mitochondrial structure [Taub, Ramirez-Sanchez, Ciaraldi, Perkins, Murphy, Naviaux, Hogan, Ceballos, Maisel, Henry et al. (2012) Clin. Trans. Sci. 5, 43-47]. We hypothesized that an improved mitochondrial structure may facilitate the reversal of detrimental alterations in sarcomeric microstructure. In a pilot study, five patients with HF and T2D consumed ERC for 3 months; treadmill testing [VO2max (maximum oxygen consumption)] and SkM biopsies were performed. Western blot analysis, immunohistochemistry and electron microscopy were used. We report severe perturbations in components of the DAPC (dystrophin-associated protein complex) as well as sarcomeric microstructure at baseline. ERC induced recovery/enhancement of DAPC protein levels, sarcomeric microstructure and, in a co-ordinated fashion, alterations in markers of SkM growth/differentiation consistent with myofibre regeneration. VO2max increased (~24%) but did not reach statistical significance. These initial results warrant further rigorous investigation, since the use of ERC (or pure epicatechin) may represent a safe and novel means of improving muscle function.


Assuntos
Cacau/química , Catequina/farmacologia , Diabetes Mellitus Tipo 2/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Músculo Esquelético/efeitos dos fármacos , Sarcômeros/efeitos dos fármacos , Idoso , Western Blotting , Catequina/administração & dosagem , Catequina/uso terapêutico , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/prevenção & controle , Disferlina , Distrofina/metabolismo , Complexo de Proteínas Associadas Distrofina/metabolismo , Teste de Esforço , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/prevenção & controle , Humanos , Imuno-Histoquímica , Masculino , Proteínas de Membrana/metabolismo , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Projetos Piloto , Sarcoglicanas/metabolismo , Sarcômeros/metabolismo , Sarcômeros/ultraestrutura , Resultado do Tratamento , Utrofina/metabolismo
20.
Bioorg Med Chem Lett ; 23(15): 4441-6, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23791569

RESUMO

Impaired mitochondrial function represents an early manifestation of endothelial dysfunction and likely contributes to the development of cardiovascular diseases (CVD). The stimulation of mitochondrial function and/or biogenesis is seen as a means to improve the bioenergetic and metabolic status of cells and thus, reduce CVD. In this study we examined the capacity of the flavanol (-)-epicatechin and two novel derivatives to enhance mitochondrial function and protein levels in cultured bovine coronary artery endothelial cells. As nitric oxide production by endothelial cells is suspected in mediating mitochondria effects (including biogenesis), we also examined the dependence of responses on this molecule using an inhibitor of nitric oxide synthase. Results indicate that the flavanol (-)-epicatechin and derivatives are capable of stimulating mitochondrial function as assessed by citrate synthase activity as well as induction of structural (porin, mitofilin) and oxidative phosporylation protein levels (complex I and II). Effects were blocked by the use of the chemical inhibitor of the synthase thus, evidencing a role for nitric oxide in mediating these effects. The results observed indicate that the three agents are effective in enhancing mitochondria function and protein content. The effects noted for (-)-epicatechin may serve to explain the healthy effects on cardiometabolic risk ascribed to the consumption of cocoa products.


Assuntos
Catequina/análogos & derivados , Proteínas Mitocondriais/metabolismo , Óxido Nítrico/metabolismo , Animais , Catequina/farmacologia , Bovinos , Células Cultivadas , Citrato (si)-Sintase/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estereoisomerismo
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