RESUMO
BACKGROUND: Impaired intestinal integrity, including increased permeability of the small bowel mucosa, has been shown in patients with celiac disease (CD) as well as with type 1 diabetes (T1D). Zonulin (ZO, pre-haptoglobin), a tight junction regulator, plays a particular role in the regulation of intestinal barrier function and in the pathogenesis of the above-mentioned diseases. AIM: To investigate whether enteroviruses (EVs) and immunoregulatory cells are associated with intestinal permeability in patients with CD alone and with coexistent T1D. MATERIALS AND METHODS: Altogether 80 patients (mean age 10.68 ± 6.69 years) who had undergone small bowel biopsy were studied. Forty patients with functional dyspepsia and normal small bowel mucosa formed the control group. The circulating ZO level in sera was evaluated using ELISA. The densities of EV, FOXP3+ regulatory T cells (Tregs), indoleamine 2,3-dioxygenase (IDO+) dendritic cells (DCs) and glutamic acid dexarboxylase (GAD)65+ cells in small bowel mucosa were investigated by immunohistochemistry. The expression analysis of FOXP3, tight junction protein 1 (TJP1), gap junction (GJA1), IDO and CD103 genes was evaluated by real-time PCR. RESULTS: The ZO level was higher in CD patients compared to subjects with a normal small bowel mucosa, particularly in those with Marsh IIIc atrophy (p = 0.01), and correlated with the density of EV (r = 0.63; p = 0.0003) and IDO+ DCs (r = 0.58; p = 0.01) in the small bowel mucosa. The density of GAD65+ epithelial cells was correlated with the density of EV (r = 0.59; p = 0.03) and IDO+ DCs (r = 0.78; p = 0.004) in CD patients. The relative expression of FOXP3 mRNA in the small bowel mucosa tissue was significantly higher in patients with CD, compared to subjects with a normal mucosa, and correlated with the density of EV (r = 0.62; p = 0.017) as well as with the relative expression of IDO mRNA (r = 0.54; p = 0.019). CONCLUSIONS: The CD is associated with elevation of the circulating ZO level, the value of which correlates with the density of EV in CD patients with severe atrophic changes in the small bowel mucosa, particularly in cases of concomitant T1D. The CD is also characterized by the close relationship of the density of GAD65+ epithelial cells with the EV, ZO level and IDO+ DCs.
Assuntos
Doença Celíaca/metabolismo , Toxina da Cólera/sangue , Células Dendríticas/patologia , Enterovirus/imunologia , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Permeabilidade , Linfócitos T Reguladores/patologia , Adolescente , Anticorpos Antivirais/imunologia , Antígenos CD/genética , Autoanticorpos/imunologia , Estudos de Casos e Controles , Doença Celíaca/complicações , Doença Celíaca/patologia , Doença Celíaca/virologia , Criança , Pré-Escolar , Conexina 43/genética , Células Dendríticas/metabolismo , Diabetes Mellitus Tipo 1/complicações , Ensaio de Imunoadsorção Enzimática , Feminino , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Glutamato Descarboxilase/imunologia , Glutamato Descarboxilase/metabolismo , Haptoglobinas , Humanos , Imunoglobulina A/imunologia , Imuno-Histoquímica , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Cadeias alfa de Integrinas/genética , Mucosa Intestinal/patologia , Mucosa Intestinal/virologia , Intestino Delgado/patologia , Intestino Delgado/virologia , Masculino , Precursores de Proteínas , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Linfócitos T Reguladores/metabolismo , Proteína da Zônula de Oclusão-1/genéticaRESUMO
BACKGROUND. Ageing is associated with suppressed regenerative potential of muscle precursor cells due to decrease of satellite cells and suppressive intramuscular milieu on their activation, associated with ageing-related low-grade inflammation. The aim of the study was to characterize the function of oxidative phosphorylation (OXPHOS), glycolysis, adenylate kinase (AK), and creatine kinase (CK) mediated systems in young and older individuals. MATERIALS AND METHODS. Myoblasts were cultivated from biopsies taken by transcutaneous conchotomy from vastus lateralis muscle in young (20-29 yrs, n = 7) and older (70-79 yrs, n = 7) subjects. Energy metabolism was assessed in passages 2 to 6 by oxygraphy and enzyme analysis. RESULTS. In myoblasts of young and older subjects the rate of OXPHOS decreased during proliferation from passages 2 to 6. The total activities of CK and AK decreased. Myoblasts of passage 2 cultivated from young muscle showed higher rate of OXPHOS and activities of CK and AK compared to myoblasts from older subjects while hexokinase and pyruvate kinase were not affected by ageing. CONCLUSIONS. Proliferation of myoblasts in vitro is associated with downregulation of OXPHOS and energy storage and transfer systems. Ageing in vivo exerts an impact on satellite cells which results in altered metabolic profile in favour of the prevalence of glycolytic pathways over mitochondrial OXPHOS of myoblasts.
Assuntos
Envelhecimento , Mioblastos/metabolismo , Adenilato Quinase/metabolismo , Adulto , Fatores Etários , Idoso , Animais , Biópsia , Proliferação de Células , Células Cultivadas , Creatina Quinase/metabolismo , Metabolismo Energético , Glicólise , Hexoquinase/metabolismo , Humanos , Inflamação , Músculo Esquelético/metabolismo , Fosforilação Oxidativa , Oxigênio/química , Piruvato Quinase/metabolismo , Células Satélites de Músculo Esquelético/citologia , Adulto JovemRESUMO
Cardiac energy metabolism with emphasis on mitochondria was addressed in atrial tissue from patients with overload-induced atrial dilation. Structural remodeling of dilated (D) atria manifested as intracellular accumulation of fibrillar aggregates, lipofuscin, signs of myolysis and autophagy. Despite impaired complex I dependent respiration and increased diffusion restriction for ADP, no changes regarding adenylate and creatine kinase occurred. We observed 7-fold overexpression of HK2 gene in D atria with concomitant 2-fold greater activation of mitochondrial oxygen consumption by glucose, which might represent an adaption to increased energy requirements and impaired mitochondrial function by effectively joining glycolysis and oxidative phosphorylation.
Assuntos
Difosfato de Adenosina/metabolismo , Cardiomiopatia Dilatada/fisiopatologia , Hexoquinase/metabolismo , Mitocôndrias/fisiologia , Miócitos Cardíacos/fisiologia , Fosforilação Oxidativa , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismoRESUMO
The aim of this review is to analyze the results of experimental research of mechanisms of regulation of mitochondrial respiration in cardiac and skeletal muscle cells in vivo obtained by using the permeabilized cell technique. Such an analysis in the framework of Molecular Systems Bioenergetics shows that the mechanisms of regulation of energy fluxes depend on the structural organization of the cells and interaction of mitochondria with cytoskeletal elements. Two types of cells of cardiac phenotype with very different structures were analyzed: adult cardiomyocytes and continuously dividing cancerous HL-1 cells. In cardiomyocytes mitochondria are arranged very regularly, and show rapid configuration changes of inner membrane but no fusion or fission, diffusion of ADP and ATP is restricted mostly at the level of mitochondrial outer membrane due to an interaction of heterodimeric tubulin with voltage dependent anion channel, VDAC. VDAC with associated tubulin forms a supercomplex, Mitochondrial Interactosome, with mitochondrial creatine kinase, MtCK, which is structurally and functionally coupled to ATP synthasome. Due to selectively limited permeability of VDAC for adenine nucleotides, mitochondrial respiration rate depends almost linearly upon the changes of cytoplasmic ADP concentration in their physiological range. Functional coupling of MtCK with ATP synthasome amplifies this signal by recycling adenine nucleotides in mitochondria coupled to effective phosphocreatine synthesis. In cancerous HL-1 cells this complex is significantly modified: tubulin is replaced by hexokinase and MtCK is lacking, resulting in direct utilization of mitochondrial ATP for glycolytic lactate production and in this way contributing in the mechanism of the Warburg effect. Systemic analysis of changes in the integrated system of energy metabolism is also helpful for better understanding of pathogenesis of many other diseases.
Assuntos
Mitocôndrias/metabolismo , Nucleotídeos de Adenina/metabolismo , Animais , Respiração Celular , Creatina Quinase Mitocondrial/metabolismo , Citoesqueleto/metabolismo , Metabolismo Energético , Retroalimentação Fisiológica , Humanos , Cinética , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Musculares/metabolismo , Modelos Biológicos , Fibras Musculares Esqueléticas/metabolismo , Miócitos Cardíacos/metabolismo , Fosfocreatina/metabolismo , Tubulina (Proteína)/metabolismo , Canais de Ânion Dependentes de Voltagem/metabolismoRESUMO
Comparative analysis of the bioenergetic parameters of adult rat cardiomyocytes (CM) and HL-1 cells with very different structure but similar cardiac phenotype was carried out with the aim of revealing the importance of the cell structure for regulation of its energy fluxes. Confocal microscopic analysis showed very different mitochondrial arrangement in these cells. The cytochrome content per milligram of cell protein was decreased in HL-1 cells by a factor of 7 compared with CM. In parallel, the respiratory chain complex activities were decreased by 4-8 times in the HL-1 cells. On the contrary, the activities of glycolytic enzymes, hexokinase (HK), and pyruvate kinase (PK) were increased in HL-1 cells, and these cells effectively transformed glucose into lactate. At the same time, the creatine kinase (CK) activity was significantly decreased in HL-1 cells. In conclusion, the results of this study comply with the assumption that in contrast to CM in which oxidative phosphorylation is a predominant provider of ATP and the CK system is a main carrier of energy from mitochondria to ATPases, in HL-1 cells the energy metabolism is based mostly on the glycolytic reactions coupled to oxidative phosphorylation through HK.
Assuntos
Transporte de Elétrons , Metabolismo Energético , Glicólise , Miócitos Cardíacos/metabolismo , Difosfato de Adenosina/metabolismo , Animais , Linhagem Celular , Creatina Quinase/metabolismo , Hexoquinase/metabolismo , Camundongos , Piruvato Quinase/metabolismo , Ratos , Ratos WistarRESUMO
The cellular energy metabolism in human musculus gluteus medius (MGM) under normal conditions and hip osteoarthritis (OA) was explored. The functions of oxidative phosphorylation and energy transport systems were analyzed in permeabilized (skinned) muscle fibers by oxygraphy, in relation to myosin heavy chain (MHC) isoform distribution profile analyzed by SDS-PAGE, and to creatine kinase (CK) and adenylate kinase (AK) activities measured spectrophotometrically in the intact muscle. The results revealed high apparent Km for ADP in regulation of respiration that decreased after addition of creatine in MGM of traumatic patients (controls). OA was associated with increased sensitivity of mitochondrial respiration to ADP, decreased total activities of AK and CK with major reduction in mi-CK fraction, and attenuated effect of creatine on apparent Km for ADP compared with control group. It also included a complete loss of type II fibers in a subgroup of patients with the severest disease grade. It is concluded that energy metabolism in MGM cells is organized into functional complexes of mitochondria and ATPases. It is suggested that because of degenerative remodeling occurring during development of OA, these complexes become structurally and functionally impaired, which results in increased access of exogenous ADP to mitochondria and dysfunction of CK-phosphotransfer system.