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1.
Cardiol Young ; 32(7): 1172-1174, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34866569

RESUMO

We report the case of a 14-year-old male presented with raised myocardial injury biomarkers, on the workout, Campylobacter coli was identified on stool culture, treated with antibiotics with total resolution. Cardiac magnetic resonance showed interventricular septum and lateral wall hypokinesia and subepicardial delayed enhancement, with preserved ventricular systolic function. To our knowledge, this is the first report linking Campylobacter coli to myopericarditis in children.


Assuntos
Campylobacter coli , Miocardite , Adolescente , Criança , Coração , Humanos , Imageamento por Ressonância Magnética , Masculino , Miocardite/diagnóstico , Sístole
2.
FASEB J ; 34(9): 12946-12962, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32772437

RESUMO

Although we have shown that catecholamines suppress the activity of the Ubiquitin-Proteasome System (UPS) and atrophy-related genes expression through a cAMP-dependent manner in skeletal muscle from rodents, the underlying mechanisms remain unclear. Here, we report that a single injection of norepinephrine (NE; 1 mg kg-1 ; s.c) attenuated the fasting-induced up-regulation of FoxO-target genes in tibialis anterior (TA) muscles by the stimulation of PKA/CREB and Akt/FoxO1 signaling pathways. In addition, muscle-specific activation of PKA by the overexpression of PKA catalytic subunit (PKAcat) suppressed FoxO reporter activity induced by (1) a wild-type; (2) a non-phosphorylatable; (3) a non-phosphorylatable and non-acetylatable forms of FoxO1 and FoxO3; (4) downregulation of FoxO protein content, and probably by (5) PGC-1α up-regulation. Consistently, the overexpression of the PKAcat inhibitor (PKI) up-regulated FoxO activity and the content of Atrogin-1 and MuRF1, as well as induced muscle fiber atrophy, the latter effect being prevented by the overexpression of a dominant negative (d. n.) form of FoxO (d.n.FoxO). The sustained overexpression of PKAcat induced fiber-type transition toward a smaller, slower, and more oxidative phenotype and improved muscle resistance to fatigue. Taken together, our data provide the first evidence that endogenous PKA activity is required to restrain the basal activity of FoxO and physiologically important to maintain skeletal muscle mass.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteína Forkhead Box O1/metabolismo , Músculo Esquelético/enzimologia , Atrofia Muscular/metabolismo , Animais , Linhagem Celular , Proteína Forkhead Box O3/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/patologia , Mioblastos Esqueléticos/enzimologia , Transdução de Sinais
3.
J Cell Sci ; 130(9): 1675-1687, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28325759

RESUMO

Tail-anchored (TA) proteins contain a single transmembrane domain (TMD) at the C-terminus that anchors them to the membranes of organelles where they mediate critical cellular processes. Accordingly, mutations in genes encoding TA proteins have been identified in a number of severe inherited disorders. Despite the importance of correctly targeting a TA protein to its appropriate membrane, the mechanisms and signals involved are not fully understood. In this study, we identify additional peroxisomal TA proteins, discover more proteins that are present on multiple organelles, and reveal that a combination of TMD hydrophobicity and tail charge determines targeting to distinct organelle locations in mammals. Specifically, an increase in tail charge can override a hydrophobic TMD signal and re-direct a protein from the ER to peroxisomes or mitochondria and vice versa. We show that subtle changes in those parameters can shift TA proteins between organelles, explaining why peroxisomes and mitochondria have many of the same TA proteins. This enabled us to associate characteristic physicochemical parameters in TA proteins with particular organelle groups. Using this classification allowed successful prediction of the location of uncharacterized TA proteins for the first time.


Assuntos
Compartimento Celular , Mamíferos/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Animais , Retículo Endoplasmático/metabolismo , Células Hep G2 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Membranas Intracelulares/metabolismo , Mitocôndrias/metabolismo , Modelos Biológicos , Peroxissomos/metabolismo , Transporte Proteico , Saccharomyces cerevisiae/metabolismo , Frações Subcelulares/metabolismo
4.
Circ Res ; 120(4): 645-657, 2017 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-28096195

RESUMO

RATIONALE: Although the second messenger cyclic AMP (cAMP) is physiologically beneficial in the heart, it largely contributes to cardiac disease progression when dysregulated. Current evidence suggests that cAMP is produced within mitochondria. However, mitochondrial cAMP signaling and its involvement in cardiac pathophysiology are far from being understood. OBJECTIVE: To investigate the role of MitEpac1 (mitochondrial exchange protein directly activated by cAMP 1) in ischemia/reperfusion injury. METHODS AND RESULTS: We show that Epac1 (exchange protein directly activated by cAMP 1) genetic ablation (Epac1-/-) protects against experimental myocardial ischemia/reperfusion injury with reduced infarct size and cardiomyocyte apoptosis. As observed in vivo, Epac1 inhibition prevents hypoxia/reoxygenation-induced adult cardiomyocyte apoptosis. Interestingly, a deleted form of Epac1 in its mitochondrial-targeting sequence protects against hypoxia/reoxygenation-induced cell death. Mechanistically, Epac1 favors Ca2+ exchange between the endoplasmic reticulum and the mitochondrion, by increasing interaction with a macromolecular complex composed of the VDAC1 (voltage-dependent anion channel 1), the GRP75 (chaperone glucose-regulated protein 75), and the IP3R1 (inositol-1,4,5-triphosphate receptor 1), leading to mitochondrial Ca2+ overload and opening of the mitochondrial permeability transition pore. In addition, our findings demonstrate that MitEpac1 inhibits isocitrate dehydrogenase 2 via the mitochondrial recruitment of CaMKII (Ca2+/calmodulin-dependent protein kinase II), which decreases nicotinamide adenine dinucleotide phosphate hydrogen synthesis, thereby, reducing the antioxidant capabilities of the cardiomyocyte. CONCLUSIONS: Our results reveal the existence, within mitochondria, of different cAMP-Epac1 microdomains that control myocardial cell death. In addition, our findings suggest Epac1 as a promising target for the treatment of ischemia-induced myocardial damage.


Assuntos
Fatores de Troca do Nucleotídeo Guanina/biossíntese , Mitocôndrias Cardíacas/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Animais Recém-Nascidos , Morte Celular/fisiologia , Células Cultivadas , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/patologia , Humanos , Masculino , Microdomínios da Membrana/metabolismo , Microdomínios da Membrana/patologia , Camundongos , Camundongos Knockout , Mitocôndrias Cardíacas/patologia , Miócitos Cardíacos/patologia , Ratos
5.
Can J Physiol Pharmacol ; 92(6): 445-54, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24826789

RESUMO

The aim of this study was to investigate the changes in the rates of both protein synthesis and breakdown, and the activation of intracellular effectors that control these processes in soleus muscles from growing rats fed a low-protein, high-carbohydrate (LPHC) diet for 15 days. The mass and the protein content, as well as the rate of protein synthesis, were decreased in the soleus from LPHC-fed rats. The availability of amino acids was diminished, since the levels of various essential amino acids were decreased in the plasma of LPHC-fed rats. Overall rate of proteolysis was also decreased, explained by reductions in the mRNA levels of atrogin-1 and MuRF-1, ubiquitin conjugates, proteasome activity, and in the activity of caspase-3. Soleus muscles from LPHC-fed rats showed increased insulin sensitivity, with increased levels of insulin receptor and phosphorylation levels of AKT, which probably explains the inhibition of both the caspase-3 activity and the ubiquitin-proteasome system. The fall of muscle proteolysis seems to represent an adaptive response that contributes to spare proteins in a condition of diminished availability of dietary amino acids. Furthermore, the decreased rate of protein synthesis may be the driving factor to the lower muscle mass gain in growing rats fed the LPHC diet.


Assuntos
Caspase 3/metabolismo , Dieta com Restrição de Proteínas , Carboidratos da Dieta/farmacologia , Músculo Esquelético/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Ubiquitina/metabolismo , Aminoácidos/sangue , Animais , Catepsina B/metabolismo , Proteínas Alimentares/administração & dosagem , Proteínas Alimentares/farmacologia , Resistência à Insulina , Masculino , Proteínas Musculares/biossíntese , Músculo Esquelético/enzimologia , Músculo Esquelético/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Receptor de Insulina/metabolismo , Proteínas Ligases SKP Culina F-Box/biossíntese , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases/biossíntese
6.
Eur Heart J Case Rep ; 7(2): ytad044, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36819889

RESUMO

Background: TANGO2-related metabolic encephalopathy and arrhythmia are a rare, newly recognized, and likely under-diagnosed condition. First described in 2016, it is characterized by developmental delay and recurrent metabolic crisis. During these episodes, patients may present QTc prolongation and ventricular arrhythmias. Case summary: A 13-year-old female, with developmental delay, presented with severe rhabdomyolysis and an initially normal electrocardiogram (ECG). Due to the worsening of rhabdomyolysis, QTc prolongation was identified (QTc 570 ms) and oral ß-blocker therapy started. A non-sustained ventricular tachycardia developed, initially managed with magnesium and lidocaine. After a short period, an arrhythmic storm of polymorphic ventricular extrasystoles induced Torsade de Pointes (TdP) was triggered. A temporary percutaneous pacing lead was placed and esmolol infusion started. The electrical instability ran in parallel with the increasing severity of rhabdomyolysis and systolic ventricular function decline. Genetic testing identified a pathogenic variant in homozygosity in the TANGO2 gene. A stable sinus rhythm was achieved with metabolic and serum electrolytes optimization. ECG showed normalization of the QTc interval. Discussion: The full TANGO2-related phenotype emerges over time and the prognosis is linked to the appearance of ECG abnormalities. QT interval prolongation can lead to life-threatening ventricular tachycardias. The arrhythmia mechanism seems to be secondary to metabolite build-up in cardiomyocytes, which can explain the cardiac phenotype during the crisis which subsides after their resolution. In these patients, avoiding bradycardia is fundamental, since long QT-related TdP seems to be triggered by bradycardia and short-long-short ventricular premature beats (VPB). During an acute metabolic crisis, the management of arrhythmias relies on metabolic control.

7.
Cureus ; 15(12): e49779, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38161557

RESUMO

Prostate cancer is the second-most common malignancy in males. Despite more frequently metastasizing to the bone, regional lymph nodes, and liver, the brain can also be affected. These metastases can simulate meningiomas, making the diagnosis more difficult. Here, we report the case of a 62-year-old male with a sudden onset of confusion and dysarthria with spontaneous resolution but amnesia for the event. On a neurological exam, the patient had left exophthalmos and palpebral ptosis. He was referred to the emergency room, where he underwent a cranioencephalic CT, which revealed a left anterior temporal lesion with adjacent edema suggestive of meningioma, later confirmed by an MRI. Due to the worsening of the symptoms and an increase in the size of the lesion, total resection was proposed. The anatomopathological study revealed a poorly differentiated carcinoma. To study the primary tumor, a CT of the thorax, abdomen, and pelvis; a spine MRI; and a complementary study with prostate-specific antigen were requested. These studies revealed a prostate adenocarcinoma with brain and bone metastases. After the diagnosis, the patient underwent hormone therapy, chemotherapy, and palliative radiotherapy.

8.
Front Pharmacol ; 14: 1188829, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37456758

RESUMO

NLRP3 inflammasome has a key role in chronic low-grade metabolic inflammation, and its excessive activation may contribute to the beginning and progression of several diseases, including hepatic insulin resistance (hIR). Thus, this review aims to highlight the role of NLRP3 inflammasome and oxidative stress in the development of hIR and evidence related to phytochemical intervention in this context. In this review, we will address the hIR pathogenesis related to reactive oxygen species (ROS) production mechanisms, involving oxidized mitochondrial DNA (ox-mtDNA) and thioredoxin interacting protein (TXNIP) induction in the NLRP3 inflammasome activation. Moreover, we discuss the inhibitory effect of bioactive compounds on the insulin signaling pathway, and the role of microRNAs (miRNAs) in the phytochemical target mechanism in ameliorating hIR. Although most of the research in the field has been focused on evaluating the inhibitory effect of phytochemicals on the NLRP3 inflammasome pathway, further investigation and clinical studies are required to provide insights into the mechanisms of action, and, thus, encourage the use of these bioactive compounds as an additional therapeutic strategy to improve hIR and correlated conditions.

9.
Prog Polym Sci ; 37(1): 1-17, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22058578

RESUMO

To overcome the limitations of traditionally used autografts, allografts and, to a lesser extent, synthetic materials, there is the need to develop a new generation of scaffolds with adequate mechanical and structural support, control of cell attachment, migration, proliferation and differentiation and with bio-resorbable features. This suite of properties would allow the body to heal itself at the same rate as implant degradation. Genetic engineering offers a route to this level of control of biomaterial systems. The possibility of expressing biological components in nature and to modify or bioengineer them further, offers a path towards multifunctional biomaterial systems. This includes opportunities to generate new protein sequences, new self-assembling peptides or fusions of different bioactive domains or protein motifs. New protein sequences with tunable properties can be generated that can be used as new biomaterials. In this review we address some of the most frequently used proteins for tissue engineering and biomedical applications and describe the techniques most commonly used to functionalize protein-based biomaterials by combining them with bioactive molecules to enhance biological performance. We also highlight the use of genetic engineering, for protein heterologous expression and the synthesis of new protein-based biopolymers, focusing the advantages of these functionalized biopolymers when compared with their counterparts extracted directly from nature and modified by techniques such as physical adsorption or chemical modification.

10.
Am J Physiol Endocrinol Metab ; 302(1): E123-33, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21952035

RESUMO

Although it is well known that administration of the selective ß(2)-adrenergic agonist clenbuterol (CB) protects muscle following denervation (DEN), the underlying molecular mechanism remains unclear. We report that in vivo treatment with CB (3 mg/kg sc) for 3 days induces antiproteolytic effects in normal and denervated rat soleus muscle via distinct mechanisms. In normal soleus muscle, CB treatment stimulates protein synthesis, inhibits Ca(2+)-dependent proteolysis, and increases the levels of calpastatin protein. On the other hand, the administration of CB to DEN rats ameliorates the loss of muscle mass, enhances the rate of protein synthesis, attenuates hyperactivation of proteasomal and lysosomal proteolysis, and suppresses the transcription of the lysosomal protease cathepsin L and of atrogin-1/MAFbx and MuRF1, two ubiquitin (Ub) ligases involved in muscle atrophy. These effects were not associated with alterations in either IGF-I content or Akt phosphorylation levels. In isolated muscles, CB (10(-6) M) treatment significantly attenuated DEN-induced overall proteolysis and upregulation in the mRNA levels of the Ub ligases. Similar responses were observed in denervated muscles exposed to 6-BNZ-cAMP (500 µM), a PKA activator. The in vitro addition of triciribine (10 µM), a selective Akt inhibitor, did not block the inhibitory effects of CB on proteolysis and Ub ligase mRNA levels. These data indicate that short-term treatment with CB mitigates DEN-induced atrophy of the soleus muscle through the stimulation of protein synthesis, downregulation of cathepsin L and Ub ligases, and consequent inhibition of lysosomal and proteasomal activities and that these effects are independent of Akt and possibly mediated by the cAMP/PKA signaling pathway.


Assuntos
Agonistas Adrenérgicos beta/uso terapêutico , Clembuterol/uso terapêutico , Lisossomos/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Inibidores de Proteases/farmacologia , Inibidores de Proteassoma , Agonistas Adrenérgicos beta/farmacologia , Animais , Catepsina L/metabolismo , Clembuterol/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/química , Ativadores de Enzimas/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Técnicas In Vitro , Lisossomos/enzimologia , Masculino , Denervação Muscular/efeitos adversos , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Músculo Esquelético/inervação , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Atrofia Muscular/enzimologia , Atrofia Muscular/metabolismo , Atrofia Muscular/prevenção & controle , Complexo de Endopeptidases do Proteassoma/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Proteínas Ligases SKP Culina F-Box/genética , Proteínas Ligases SKP Culina F-Box/metabolismo , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
11.
Mol Metab ; 60: 101492, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35390501

RESUMO

OBJECTIVE: Although it is well established that urocortin 2 (Ucn2), a peptide member of the corticotrophin releasing factor (CRF) family, and its specific corticotrophin-releasing factor 2 receptor (CRF2R) are highly expressed in skeletal muscle, the role of this peptide in the regulation of skeletal muscle mass and protein metabolism remains elusive. METHODS: To elucidate the mechanisms how Ucn2 directly controls protein metabolism in skeletal muscles of normal mice, we carried out genetic tools, physiological and molecular analyses of muscles in vivo and in vitro. RESULTS: Here, we demonstrated that Ucn2 overexpression activated cAMP signaling and promoted an expressive muscle hypertrophy associated with higher rates of protein synthesis and activation of Akt/mTOR and ERK1/2 signaling pathways. Furthermore, Ucn2 induced a decrease in mRNA levels of atrogin-1 and in autophagic flux inferred by an increase in the protein content of LC3-I, LC3-II and p62. Accordingly, Ucn2 reduced both the transcriptional activity of FoxO in vivo and the overall protein degradation in vitro through an inhibition of lysosomal proteolytic activity. In addition, we demonstrated that Ucn2 induced a fast-to-slow fiber type shift and improved fatigue muscle resistance, an effect that was completely blocked in muscles co-transfected with mitogen-activated protein kinase phosphatase 1 (MKP-1), but not with dominant-negative Akt mutant (Aktmt). CONCLUSIONS: These data suggest that Ucn2 triggers an anabolic and anti-catabolic response in skeletal muscle of normal mice probably through the activation of cAMP cascade and participation of Akt and ERK1/2 signaling. These findings open new perspectives in the development of therapeutic strategies to cope with the loss of muscle mass.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Proteínas Proto-Oncogênicas c-akt , Urocortinas/metabolismo , Hormônio Adrenocorticotrópico/metabolismo , Hormônio Adrenocorticotrópico/farmacologia , Animais , Hipertrofia/metabolismo , Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Camundongos , Músculo Esquelético/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Urocortinas/farmacologia
12.
Arch Physiol Biochem ; : 1-15, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36328030

RESUMO

CONTEXT: The role of silymarin in hepatic lipid dysfunction and its possible mechanisms of action were investigated. OBJECTIVE: To evaluate the effects of silymarin on hepatic and metabolic profiles in mice fed with 30% fructose for 8 weeks. METHODS: We evaluated the antioxidant profile of silymarin; mice consumed 30% fructose and were treated with silymarin (120 mg/kg/day or 240 mg/kg/day). We performed biochemical, redox status, and histopathological assays. RT-qPCR was performed to detect ACC-1, ACC-2, FAS, and CS expression, and western blotting to detect PGC-1α levels. RESULTS: Silymarin contains high levels of phenolic compounds and flavonoids and exhibited significant antioxidant capacity in vitro. In vivo, the fructose-fed groups showed increased levels of AST, ALT, SOD/CAT, TBARS, hepatic TG, and cholesterol, as well as hypertriglyceridaemia, hypercholesterolaemia, and increased ACC-1 and FAS. Silymarin treatment reduced these parameters and increased mRNA levels and activity of hepatic citrate synthase. CONCLUSIONS: These results suggest that silymarin reduces worsening of NAFLD.

13.
Biomacromolecules ; 12(5): 1675-85, 2011 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-21370930

RESUMO

Atomic force microscopy (AFM) was used to assess a new chimeric protein consisting of a fusion protein of the consensus repeat for Nephila clavipes spider dragline protein and bone sialoprotein (6mer+BSP). The elastic modulus of this protein in film form was assessed through force curves, and film surface roughness was also determined. The results showed a significant difference among the elastic modulus of the chimeric silk protein, 6mer+BSP, and control films consisting of only the silk component (6mer). The behavior of the 6mer+BSP and 6mer proteins in aqueous solution in the presence of calcium (Ca) ions was also assessed to determine interactions between the inorganic and organic components related to bone interactions, anchoring, and biomaterial network formation. The results demonstrated the formation of protein networks in the presence of Ca(2+) ions, characteristics that may be important in the context of controlling materials assembly and properties related to bone formation with this new chimeric silk-BSP protein.


Assuntos
Regeneração Óssea , Osso e Ossos/química , Proteínas Recombinantes de Fusão/química , Sialoglicoproteínas/química , Seda/química , Sequência de Aminoácidos , Animais , Materiais Biocompatíveis , Dicroísmo Circular , Clonagem Molecular , Microscopia de Força Atômica , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Proteínas Recombinantes de Fusão/genética , Sialoglicoproteínas/genética , Aranhas
14.
Peptides ; 146: 170677, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34695513

RESUMO

Calcitonin Gene-Related Peptide (CGRP) is a potent vasodilator peptide widely distributed in the central nervous system and various peripheral tissues, including cardiac muscle. However, its role in heart protein metabolism remains unknown. We examined the acute effects of CGRP on autophagy and the related signaling pathways in the heart mice and cultured neonatal cardiomyocytes. CGRP (100 µg kg-1; s.c.) or 0.9 % saline was injected in awake male C57B16 mice, and the metabolic profile was determined up to 60 min. In fed mice, CGRP drastically increased glycemia and reduced insulinemia, an effect that was accompanied by reduced cardiac phosphorylation levels of Akt at Ser473 without affecting FoxO. Despite these catabolic effects, CGRP acutely inhibited autophagy as estimated by the decrease in LC3II:LC3I and autophagic flux. In addition, the fasting-induced autophagic flux in mice hearts was entirely abrogated by one single injection of CGRP. In parallel, CGRP stimulated PKA/CREB and mTORC1 signaling and increased the phosphorylation of Unc51-like kinase-1 (ULK1), an essential protein in autophagy initiation. Similar effects were observed in cardiomyocytes, in which CGRP also inhibited autophagic flux and stimulated Akt and FoxO phosphorylation. These findings suggest that CGRP in vivo acutely suppresses autophagy in the heart of fed and fasted mice, most likely through the activation of PKA/mTORC1 signaling but independent of Akt.


Assuntos
Autofagia/efeitos dos fármacos , Peptídeo Relacionado com Gene de Calcitonina/fisiologia , Coração/efeitos dos fármacos , Animais , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Camundongos , Miócitos Cardíacos/efeitos dos fármacos , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
15.
Sci Rep ; 11(1): 15042, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294826

RESUMO

The lung is inhabited by a diverse microbiome that originates from the oropharynx by a mechanism of micro-aspiration. Its bacterial biomass is usually low; however, this condition shifts in lung cancer (LC), chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD). These chronic lung disorders (CLD) may coexist in the same patient as comorbidities and share common risk factors, among which the microbiome is included. We characterized the microbiome of 106 bronchoalveolar lavages. Samples were initially subdivided into cancer and non-cancer and high-throughput sequenced for the 16S rRNA gene. Additionally, we used a cohort of 25 CLD patients where crossed comorbidities were excluded. Firmicutes, Proteobacteria and Bacteroidetes were the most prevalent phyla independently of the analyzed group. Streptococcus and Prevotella were associated with LC and Haemophilus was enhanced in COPD versus ILD. Although no significant discrepancies in microbial diversity were observed between cancer and non-cancer samples, statistical tests suggested a gradient across CLD where COPD and ILD displayed the highest and lowest alpha diversities, respectively. Moreover, COPD and ILD were separated in two clusters by the unweighted UniFrac distance (P value = 0.0068). Our results support the association of Streptoccocus and Prevotella with LC and of Haemophilus with COPD, and advocate for specific CLD signatures.


Assuntos
Brônquios/microbiologia , Pneumopatias/epidemiologia , Pneumopatias/etiologia , Microbiota , Alvéolos Pulmonares/microbiologia , Biomarcadores , Doença Crônica , Comorbidade , Feminino , Humanos , Pneumopatias/diagnóstico , Masculino , Portugal , Vigilância em Saúde Pública , RNA Ribossômico 16S
16.
Life Sci ; 278: 119563, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33930364

RESUMO

AIM: There is growing evidence about the ability of cyclic adenosine monophosphate (cAMP) signaling and nonselective phosphodiesterase (PDE) inhibitors on mitigate muscle atrophy. PDE4 accounts for the major cAMP hydrolyzing activity in skeletal muscles, therefore advances are necessary about the consequences of treatment with PDE4 inhibitors on protein breakdown in atrophied muscles. We postulated that rolipram (selective PDE4 inhibitor) may activate cAMP downstream effectors, inhibiting proteolytic systems in skeletal muscles of diabetic rats. MAIN METHODS: Streptozotocin-induced diabetic rats were treated with 2 mg/kg rolipram for 3 days. Changes in the levels of components belonging to the proteolytic machineries in soleus and extensor digitorum longus (EDL) muscles were investigated, as well as cAMP effectors. KEY FINDINGS: Treatment of diabetic rats with rolipram decreased the levels of atrogin-1 and MuRF-1 in soleus and EDL, and reduced the activities of calpains and caspase-3; these findings partially explains the low ubiquitin conjugates levels and the decreased proteasome activity. The inhibition of muscle proteolysis may be occurring due to phosphorylation and inhibition of forkhead box O (FoxO) factors, probably as a consequence of the increased cAMP levels, followed by the activation of PKA and Akt effectors. Akt activation may be associated with the increased levels of exchange protein directly activated by cAMP (EPAC). As a result, rolipram treatment spared muscle mass in diabetic rats. SIGNIFICANCE: The antiproteolytic responses associated with PDE4 inhibition may be helpful to motivate future investigations about the repositioning of PDE4 inhibitors for the treatment of muscle wasting conditions.


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Diabetes Mellitus Experimental/metabolismo , Músculo Esquelético/metabolismo , Proteínas do Tecido Nervoso/antagonistas & inibidores , Inibidores da Fosfodiesterase 4/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Calpaína/metabolismo , Caspase 3/metabolismo , AMP Cíclico/metabolismo , Masculino , Atrofia Muscular/metabolismo , Fosforilação , Complexo de Endopeptidases do Proteassoma/metabolismo , Ratos , Ratos Wistar , Rolipram/farmacologia , Transdução de Sinais/efeitos dos fármacos
17.
J Appl Physiol (1985) ; 128(4): 855-871, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32027543

RESUMO

The sympathetic nervous system (SNS) activates cAMP signaling and promotes trophic effects on brown adipose tissue (BAT) through poorly understood mechanisms. Because norepinephrine has been found to induce antiproteolytic effects on muscle and heart, we hypothesized that the SNS could inhibit autophagy in interscapular BAT (IBAT). Here, we describe that selective sympathetic denervation of rat IBAT kept at 25°C induced atrophy, and in parallel dephosphorylated forkhead box class O (FoxO), and increased cathepsin activity, autophagic flux, autophagosome formation, and expression of autophagy-related genes. Conversely, cold stimulus (4°C) for up to 72 h induced thermogenesis and IBAT hypertrophy, an anabolic effect that was associated with inhibition of cathepsin activity, autophagic flux, and autophagosome formation. These effects were abrogated by sympathetic denervation, which also upregulated Gabarapl1 mRNA. In addition, the cold-driven sympathetic activation stimulated the mechanistic target of rapamycin (mTOR) pathway, leading to the enhancement of protein synthesis, evaluated in vivo by puromycin incorporation, and to the inhibitory phosphorylation of Unc51-like kinase-1, a key protein in the initiation of autophagy. This coincided with a higher content of exchange protein-1 directly activated by cAMP (Epac1), a cAMP effector, and phosphorylation of Akt at Thr308, all these effects being abolished by denervation. Systemic treatment with norepinephrine for 72 h mimicked most of the cold effects on IBAT. These data suggest that the noradrenergic sympathetic inputs to IBAT restrain basal autophagy via suppression of FoxO and, in the setting of cold, stimulate protein synthesis via the Epac/Akt/mTOR-dependent pathway and suppress the autophagosome formation, probably through posttranscriptional mechanisms.NEW & NOTEWORTHY The underlying mechanisms related to the anabolic role of sympathetic innervation on brown adipose tissue (BAT) are unclear. We show that sympathetic denervation activates autophagic-lysosomal degradation, leading to a loss of mitochondrial proteins and BAT atrophy. Conversely, cold-driven sympathetic activation suppresses autophagy and stimulates protein synthesis, leading to BAT hypertrophy. Given its high-potential capacity for heat production, understanding the mechanisms that contribute to BAT mass is important to optimize chances of survival for endotherms in cold ambients.


Assuntos
Tecido Adiposo Marrom , Termogênese , Animais , Autofagia , Temperatura Baixa , Lisossomos , Ratos , Sistema Nervoso Simpático
18.
Sci Rep ; 9(1): 12838, 2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492894

RESUMO

The lung is a complex ecosystem of host cells and microbes often disrupted in pathological conditions. Although bacteria have been hypothesized as agents of carcinogenesis, little is known about microbiota profile of the most prevalent cancer subtypes: adenocarcinoma (ADC) and squamous cell carcinoma (SCC). To characterize lung cancer (LC) microbiota a first a screening was performed through a pooled sequencing approach of 16S ribosomal RNA gene (V3-V6) using a total of 103 bronchoalveaolar lavage fluid samples. Then, identified taxa were used to inspect 1009 cases from The Cancer Genome Atlas and to annotate tumor unmapped RNAseq reads. Microbial diversity was analyzed per cancer subtype, history of cigarette smoking and airflow obstruction, among other clinical data. We show that LC microbiota is enriched in Proteobacteria and more diverse in SCC than ADC, particularly in males and heavier smokers. High frequencies of Proteobacteria were found to discriminate a major cluster, further subdivided into well-defined communities' associated with either ADC or SCC. Here, a SCC subcluster differing from other cases by a worse survival was correlated with several Enterobacteriaceae. Overall, this study provides first evidence for a correlation between lung microbiota and cancer subtype and for its influence on patient life expectancy.


Assuntos
Adenocarcinoma/microbiologia , Carcinoma de Células Escamosas/microbiologia , Neoplasias Pulmonares/microbiologia , Pulmão/microbiologia , Microbiota , Adenocarcinoma/diagnóstico , Biodiversidade , Biomarcadores/metabolismo , Carcinoma de Células Escamosas/diagnóstico , Diagnóstico Diferencial , Seguimentos , Humanos , Neoplasias Pulmonares/diagnóstico , Prognóstico , Análise de Sobrevida
20.
Am J Clin Dermatol ; 19(1): 33-50, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28656563

RESUMO

Graft-versus-host disease (GVHD) is an immunological reaction and a frequent complication following allogeneic hematopoietic stem cell transplantation. It is associated with high mortality rates and may have a significant negative impact on the patient's quality of life, particularly in the chronic-stage setting. Many different organs can be involved, which leads to a wide range of clinical manifestations. In this context, dermatologists play a key role by diagnosing and treating GVHD from the outset since cutaneous features are not just the most common but are also usually the presenting sign. Several skin-direct therapies are available and may be indicated as monotherapy or adjuvant treatment in order to allow faster tapering and withdrawal of systemic immunosuppression. Treatment of steroid-refractory patients remains a challenge and, to date, no consensus has been reached for one single agent in second-line therapy. This article aims to review skin involvement as well as provide and update discussion on therapeutic options for both acute and chronic cutaneous GVHD.


Assuntos
Fármacos Dermatológicos/uso terapêutico , Doença Enxerto-Hospedeiro/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Terapia de Imunossupressão/métodos , Dermatopatias/terapia , Doença Aguda/terapia , Administração Cutânea , Administração Intravenosa , Administração Oral , Biomarcadores/análise , Doença Crônica/terapia , Glucocorticoides/uso terapêutico , Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/mortalidade , Humanos , Qualidade de Vida , Pele/imunologia , Dermatopatias/diagnóstico , Dermatopatias/imunologia , Dermatopatias/mortalidade
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