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1.
FASEB J ; 33(4): 5168-5180, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30620616

RESUMO

The Sarcolab pilot study of 2 crewmembers, investigated before and after a 6-mo International Space Station mission, has demonstrated the substantial muscle wasting and weakness, along with disruption of muscle's oxidative metabolism. The present work aimed at evaluating the pro/anti-inflammatory status in the same 2 crewmembers (A, B). Blood circulating (c-)microRNAs (miRs), c-proteasome, c-mitochondrial DNA, and cytokines were assessed by real-time quantitative PCR or ELISA tests. Time series analysis was performed ( i.e., before flight and after landing) at 1 and 15 d of recovery (R+1 and R+15, respectively). C-biomarkers were compared with an age-matched control population and with 2-dimensional proteomic analysis of the 2 crewmembers' muscle biopsies. Striking differences were observed between the 2 crewmembers at R+1, in terms of inflamma-miRs (c-miRs-21-5p, -126-3p, and -146a-5p), muscle specific (myo)-miR-206, c-proteasome, and IL-6/leptin, thus making the 2 astronauts dissimilar to each other. Final recovery levels of c-proteasome, c-inflamma-miRs, and c-myo-miR-206 were not reverted to the baseline values in crewmember A. In both crewmembers, myo-miR-206 changed significantly after recovery. Muscle biopsy of astronaut A showed an impressive 80% increase of α-1-antitrypsin, a target of miR-126-3p. These results point to a strong stress response induced by spaceflight involving muscle tissue and the proinflammatory setting, where inflamma-miRs and myo-miR-206 mediate the systemic recovery phase after landing.-Capri, M., Morsiani, C., Santoro, A., Moriggi, M., Conte, M., Martucci, M., Bellavista, E., Fabbri, C., Giampieri, E., Albracht, K., Flück, M., Ruoss, S., Brocca, L., Canepari, M., Longa, E., Di Giulio, I., Bottinelli, R., Cerretelli, P., Salvioli, S., Gelfi, C., Franceschi, C., Narici, M., Rittweger, J. Recovery from 6-month spaceflight at the International Space Station: muscle-related stress into a proinflammatory setting.


Assuntos
Inflamação/metabolismo , Proteínas Musculares/metabolismo , Voo Espacial , Astronautas , Biomarcadores/metabolismo , Citocinas/metabolismo , DNA Mitocondrial/metabolismo , Humanos , Inflamação/imunologia , Leptina/metabolismo , MicroRNAs/metabolismo , Músculo Esquelético/metabolismo , Projetos Piloto , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteômica
2.
Nutr Rev ; 75(6): 442-455, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28595318

RESUMO

A coherent set of epidemiological data shows that the Mediterranean diet has beneficial effects capable of preventing a variety of age-related diseases in which low-grade, chronic inflammation/inflammaging plays a major role, but the underpinning mechanism(s) is/are still unclear. It is suggested here that the Mediterranean diet can be conceptualized as a form of chronic hormetic stress, similar to what has been proposed regarding calorie restriction, the most thoroughly studied nutritional intervention. Data on the presence in key Mediterranean foods of a variety of compounds capable of exerting hormetic effects are summarized, and the mechanistic role of the nuclear factor erythroid 2 pathway is highlighted. Within this conceptual framework, particular attention has been devoted to the neurohormetic and neuroprotective properties of the Mediterranean diet, as well as to its ability to maintain an optimal balance between pro- and anti-inflammaging. Finally, the European Commission-funded project NU-AGE is discussed because it addresses a number of variables not commonly taken into consideration, such as age, sex, and ethnicity/genetics, that can modulate the hormetic effect of the Mediterranean diet.


Assuntos
Envelhecimento/genética , Dieta Mediterrânea , Estilo de Vida Saudável , Hormese , Inflamação/dietoterapia , Envelhecimento/fisiologia , Carboidratos da Dieta/administração & dosagem , Fibras na Dieta/administração & dosagem , Microbioma Gastrointestinal , Humanos , Inflamação/prevenção & controle , Fator 2 Relacionado a NF-E2/fisiologia , Estudos Observacionais como Assunto , Compostos Fitoquímicos/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Estresse Fisiológico , Vitaminas/administração & dosagem
3.
Sci Rep ; 7: 43718, 2017 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-28276434

RESUMO

Osteopontin is a pleiotropic cytokine that is involved in several diseases including multiple sclerosis. Secreted osteopontin is cleaved by few known proteases, modulating its pro-inflammatory activities. Here we show by in vitro experiments that secreted osteopontin can be processed by extracellular proteasomes, thereby producing fragments with novel chemotactic activity. Furthermore, osteopontin reduces the release of proteasomes in the extracellular space. The latter phenomenon seems to occur in vivo in multiple sclerosis, where it reflects the remission/relapse alternation. The extracellular proteasome-mediated inflammatory pathway may represent a general mechanism to control inflammation in inflammatory diseases.


Assuntos
Esclerose Múltipla/metabolismo , Osteopontina/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Sequência de Aminoácidos , Quimiotaxia/imunologia , Células Endoteliais/metabolismo , Espaço Extracelular/metabolismo , Vesículas Extracelulares/imunologia , Vesículas Extracelulares/metabolismo , Humanos , Linfócitos/imunologia , Linfócitos/metabolismo , Modelos Moleculares , Esclerose Múltipla/imunologia , Osteopontina/química , Osteopontina/imunologia , Complexo de Endopeptidases do Proteassoma/imunologia , Conformação Proteica , Relação Estrutura-Atividade
4.
Aging Cell ; 16(2): 262-272, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27995756

RESUMO

To understand why livers from aged donors are successfully used for transplants, we looked for markers of liver aging in 71 biopsies from donors aged 12-92 years before transplants and in 11 biopsies after transplants with high donor-recipient age-mismatch. We also assessed liver function in 36 age-mismatched recipients. The major findings were the following: (i) miR-31-5p, miR-141-3p, and miR-200c-3p increased with age, as assessed by microRNAs (miRs) and mRNA transcript profiling in 12 biopsies and results were validated by RT-qPCR in a total of 58 biopsies; (ii) telomere length measured by qPCR in 45 samples showed a significant age-dependent shortage; (iii) a bioinformatic approach combining transcriptome and miRs data identified putative miRs targets, the most informative being GLT1, a glutamate transporter expressed in hepatocytes. GLT1 was demonstrated by luciferase assay to be a target of miR-31-5p and miR-200c-3p, and both its mRNA (RT-qPCR) and protein (immunohistochemistry) significantly decreased with age in liver biopsies and in hepatic centrilobular zone, respectively; (iv) miR-31-5p, miR-141-3p and miR-200c-3p expression was significantly affected by recipient age (older environment) as assessed in eleven cases of donor-recipient extreme age-mismatch; (v) the analysis of recipients plasma by N-glycans profiling, capable of assessing liver functions and biological age, showed that liver function recovered after transplants, independently of age-mismatch, and recipients apparently 'rejuvenated' according to their glycomic age. In conclusion, we identified new markers of aging in human liver, their relevance in donor-recipient age-mismatches in transplantation, and offered positive evidence for the use of organs from old donors.


Assuntos
Envelhecimento/genética , Proteínas de Transporte de Glutamato da Membrana Plasmática/metabolismo , Transplante de Fígado , Fígado/metabolismo , MicroRNAs/metabolismo , Doadores de Tecidos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Transportador 2 de Aminoácido Excitatório , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Células HEK293 , Humanos , Imuno-Histoquímica , Luciferases/metabolismo , MicroRNAs/genética , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Telômero/metabolismo , Fatores de Elongação da Transcrição/genética , Fatores de Elongação da Transcrição/metabolismo , Adulto Jovem
5.
Elife ; 4: e07545, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26393687

RESUMO

Proteasomal protein degradation is a key determinant of protein half-life and hence of cellular processes ranging from basic metabolism to a host of immunological processes. Despite its importance the mechanisms regulating proteasome activity are only incompletely understood. Here we use an iterative and tightly integrated experimental and modelling approach to develop, explore and validate mechanistic models of proteasomal peptide-hydrolysis dynamics. The 20S proteasome is a dynamic enzyme and its activity varies over time because of interactions between substrates and products and the proteolytic and regulatory sites; the locations of these sites and the interactions between them are predicted by the model, and experimentally supported. The analysis suggests that the rate-limiting step of hydrolysis is the transport of the substrates into the proteasome. The transport efficiency varies between human standard- and immuno-proteasomes thereby impinging upon total degradation rate and substrate cleavage-site usage.


Assuntos
Regulação da Expressão Gênica , Complexo de Endopeptidases do Proteassoma/metabolismo , Animais , Linhagem Celular , Humanos , Cinética , Fígado/enzimologia , Camundongos , Modelos Biológicos , Transporte Proteico , Proteólise
6.
Brain Behav Immun ; 49: 188-96, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26044087

RESUMO

The proteasome is the core of the ubiquitin-proteasome system and is involved in synaptic protein metabolism. The incorporation of three inducible immuno-subunits into the proteasome results in the generation of the so-called immunoproteasome, which is endowed of pathophysiological functions related to immunity and inflammation. In healthy human brain, the expression of the key catalytic ß5i subunit of the immunoproteasome is almost absent, while it is induced in the epileptogenic foci surgically resected from patients with pharmaco-resistant seizures, including temporal lobe epilepsy. We show here that the ß5i immuno-subunit is induced in experimental epilepsy, and its selective pharmacological inhibition significantly prevents, or delays, 4-aminopyridine-induced seizure-like events in acute rat hippocampal/entorhinal cortex slices. These effects are stronger in slices from epileptic vs normal rats, likely due to the more prominent ß5i subunit expression in neurons and glia cells of diseased tissue. ß5i subunit is transcriptionally induced in epileptogenic tissue likely by Toll-like receptor 4 signaling activation, and independently on promoter methylation. The recent availability of selective ß5i subunit inhibitors opens up novel therapeutic opportunities for seizure inhibition in drug-resistant epilepsies.


Assuntos
Epilepsia/enzimologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Animais , Modelos Animais de Doenças , Córtex Entorrinal/fisiopatologia , Epilepsia/fisiopatologia , Hipocampo/fisiopatologia , Masculino , Oligopeptídeos/farmacologia , Inibidores de Proteassoma/farmacologia , Subunidades Proteicas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar
7.
Nutrients ; 7(4): 2589-621, 2015 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-25859884

RESUMO

Aging is considered the major risk factor for cancer, one of the most important mortality causes in the western world. Inflammaging, a state of chronic, low-level systemic inflammation, is a pervasive feature of human aging. Chronic inflammation increases cancer risk and affects all cancer stages, triggering the initial genetic mutation or epigenetic mechanism, promoting cancer initiation, progression and metastatic diffusion. Thus, inflammaging is a strong candidate to connect age and cancer. A corollary of this hypothesis is that interventions aiming to decrease inflammaging should protect against cancer, as well as most/all age-related diseases. Epidemiological data are concordant in suggesting that the Mediterranean Diet (MD) decreases the risk of a variety of cancers but the underpinning mechanism(s) is (are) still unclear. Here we review data indicating that the MD (as a whole diet or single bioactive nutrients typical of the MD) modulates multiple interconnected processes involved in carcinogenesis and inflammatory response such as free radical production, NF-κB activation and expression of inflammatory mediators, and the eicosanoids pathway. Particular attention is devoted to the capability of MD to affect the balance between pro- and anti-inflammaging as well as to emerging topics such as maintenance of gut microbiota (GM) homeostasis and epigenetic modulation of oncogenesis through specific microRNAs.


Assuntos
Envelhecimento , Dieta Mediterrânea , Inflamação/prevenção & controle , Neoplasias/prevenção & controle , Doença Crônica , Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Humanos
9.
Biogerontology ; 16(3): 329-40, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25559404

RESUMO

Sarcopenia, the progressive loss of muscle mass and strength, is a phenomenon characterizing human aging whose etiology is still not clear. While there is increasing evidence for the influence of inter-muscular adipose tissue infiltration in the development of sarcopenia, much less is known about a possible role for intra-muscular triglycerides (IMTG). IMTG accumulate in form of lipid droplets decorated by proteins such as Perilipins (Plins). In skeletal muscle the most abundant are Plin2 and Plin5. In this study we compared the expression of these two Plins in Vastus lateralis muscle samples of subjects of different age, both healthy donors (HD) and patients with limited lower limb mobility (LLMI). These latter are characterized by a condition of chronic physical inactivity. Plin2 expression resulted higher in old age for both HD and LLMI patients, while Plin5 slightly decreased only in LLMI patients. Moreover, in these patients, only Plin2 was associated with the decrease of muscle strength and the expression of factors related to muscle atrophy (MuRF1, Atrogin and p53). An increase in Plin2 and a concomitant decrease of Plin5 was also observed when we considered animal model of disuse-induced muscle atrophy. As a whole, these data indicate that Plin2 and Plin5 have a different expression pattern during muscle aging and inactivity, and only Plin2 appears to be associated with functional alterations of the muscle.


Assuntos
Envelhecimento/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Proteínas de Membrana/metabolismo , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Proteínas/metabolismo , Sarcopenia/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Animais , Biópsia , Estudos de Casos e Controles , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Humanos , Masculino , Proteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Pessoa de Meia-Idade , Limitação da Mobilidade , Modelos Animais , Denervação Muscular , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Força Muscular/fisiologia , Músculo Esquelético/patologia , Atrofia Muscular/genética , Perilipina-2 , Perilipina-5 , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Proteínas/genética , Sarcopenia/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas com Motivo Tripartido , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
10.
Mech Ageing Dev ; 141-142: 26-34, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25265087

RESUMO

Owing to organ shortage, livers from old donors are increasingly used for transplantation. The function and duration of such transplanted livers are apparently comparable to those from young donors, suggesting that, despite some morphological and structural age-related changes, no major functional changes do occur in liver with age. We tested this hypothesis by performing a comprehensive study on proteasomes, major cell organelles responsible for proteostasis, in liver biopsies from heart-beating donors. Oxidized and poly-ubiquitin conjugated proteins did not accumulate with age and the three major proteasome proteolytic activities were similar in livers from young and old donors. Analysis of proteasomes composition showed an age-related increased of ß5i/α4 ratio, suggesting a shift toward proteasomes containing inducible subunits and a decreased content of PA28α subunit, mainly in the cytosol of hepatocytes. Thus our data suggest that, proteasomes activity is well preserved in livers from aged donors, concomitantly with subtle changes in proteasome subunit composition which might reflect the occurrence of a functional remodelling to maintain an efficient proteostasis. Gender differences are emerging and they deserve further investigations owing to the different aging trajectories between men and women. Finally, our data support the safe use of livers from old donors for transplantation.


Assuntos
Envelhecimento/metabolismo , Fígado/enzimologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Caracteres Sexuais , Adolescente , Adulto , Feminino , Humanos , Fígado/citologia , Masculino , Pessoa de Meia-Idade
11.
Autoimmune Dis ; 2014: 739705, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24523959

RESUMO

The ubiquitin-proteasome system is the major intracellular molecular machinery for protein degradation and maintenance of protein homeostasis in most human cells. As ubiquitin-proteasome system plays a critical role in the regulation of the immune system, it might also influence the development and progression of multiple sclerosis (MS). Both ex vivo analyses and animal models suggest that activity and composition of ubiquitin-proteasome system are altered in MS. Proteasome isoforms endowed of immunosubunits may affect the functionality of different cell types such as CD8(+) and CD4(+) T cells and B cells as well as neurons during MS development. Furthermore, the study of proteasome-related biomarkers, such as proteasome antibodies and circulating proteasomes, may represent a field of interest in MS. Proteasome inhibitors are already used as treatment for cancer and the recent development of inhibitors selective for immunoproteasome subunits may soon represent novel therapeutic approaches to the different forms of MS. In this review we describe the current knowledge on the potential role of proteasomes in MS and discuss the pro et contra of possible therapies for MS targeting proteasome isoforms.

12.
PLoS One ; 8(8): e73709, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23977392

RESUMO

Human aging is associated with a progressive loss of muscle mass and strength and a concomitant fat accumulation in form of inter-muscular adipose tissue, causing skeletal muscle function decline and immobilization. Fat accumulation can also occur as intra-muscular triglycerides (IMTG) deposition in lipid droplets, which are associated with perilipin proteins, such as Perilipin2 (Plin2). It is not known whether Plin2 expression changes with age and if this has consequences on muscle mass and strength. We studied the expression of Plin2 in the vastus lateralis (VL) muscle of both healthy subjects and patients affected by lower limb mobility limitation of different age. We found that Plin2 expression increases with age, this phenomenon being particularly evident in patients. Moreover, Plin2 expression is inversely correlated with quadriceps strength and VL thickness. To investigate the molecular mechanisms underpinning this phenomenon, we focused on IGF-1/p53 network/signalling pathway, involved in muscle physiology. We found that Plin2 expression strongly correlates with increased p53 activation and reduced IGF-1 expression. To confirm these observations made on humans, we studied mice overexpressing muscle-specific IGF-1, which are protected from sarcopenia. These mice resulted almost negative for the expression of Plin2 and p53 at two years of age. We conclude that fat deposition within skeletal muscle in form of Plin2-coated lipid droplets increases with age and is associated with decreased muscle strength and thickness, likely through an IGF-1- and p53-dependent mechanism. The data also suggest that excessive intramuscular fat accumulation could be the initial trigger for p53 activation and consequent loss of muscle mass and strength.


Assuntos
Proteínas de Membrana/metabolismo , Debilidade Muscular/metabolismo , Debilidade Muscular/patologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Sarcopenia/metabolismo , Sarcopenia/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Camundongos , Força Muscular , Debilidade Muscular/complicações , Debilidade Muscular/fisiopatologia , Músculo Esquelético/fisiopatologia , Perilipina-2 , Sarcopenia/complicações , Sarcopenia/fisiopatologia , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo , Adulto Jovem
13.
Curr Pharm Des ; 19(9): 1675-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23589904

RESUMO

Inflamm-aging, that is the age-associated inflammatory status, is considered one of the most striking consequences of immunosenescence, as it is believed to be linked to the majority of age-associated diseases sharing an inflammatory basis. Nevertheless, evidence is emerging that inflamm-aging is at least in part independent from immunological stimuli. Moreover, centenarians who avoided or delayed major inflammatory diseases display markers of inflammation. In this paper we proposed a reappraisal of the concept of inflamm-aging, suggesting that its pathological effects can be independent from the total amount of pro-inflammatory mediators, but they would be rather associated with the anatomical district and type of cells where they are produced and where they primarily act.


Assuntos
Envelhecimento , Senescência Celular , Sistema Imunitário/fisiologia , Inflamação/fisiopatologia , Longevidade , Apoptose , DNA/sangue , Humanos
14.
Curr Pharm Des ; 19(4): 702-18, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23016859

RESUMO

Immunoproteasome is an emerging biological target that constitutes a key element not only in antigen presentation but also in T cell and cytokine regulation as well as cellular homeostasis. Respect to standard proteasome, the inducible expression and different sensitivity towards activity modulators of immunoproteasome render it a potential therapeutic target for tumours and central nervous system diseases. In this review we report the cutting edge studies for understanding when immunoproteasome expression is induced and how it regulates pivotal pathways involved in tumours and neuropathologies, including apoptosis and inflammation. We emphasize its role as a new pharmacological target by describing the recent medicinal chemistry efforts aimed at design selective small-molecule modulators of both standard- and immuno-proteasome forms. Finally, we also present an in silico model of the human immunoproteasome structure by the major molecular differences with the 20S standard proteasome and discuss the perspective for the design of novel specific smallmolecule modulators for the different proteasome isoforms.


Assuntos
Doenças do Sistema Nervoso Central/tratamento farmacológico , Neoplasias/tratamento farmacológico , Complexo de Endopeptidases do Proteassoma/imunologia , Animais , Apresentação de Antígeno/imunologia , Apoptose/imunologia , Doenças do Sistema Nervoso Central/imunologia , Simulação por Computador , Citocinas/imunologia , Desenho de Fármacos , Humanos , Terapia de Alvo Molecular , Neoplasias/imunologia , Isoformas de Proteínas , Linfócitos T/imunologia
15.
PLoS One ; 7(3): e32678, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22403694

RESUMO

Inflammation is part of a complex physiological response to harmful stimuli and pathogenic stress. The five components of the Nuclear Factor κB (NF-κB) family are prominent mediators of inflammation, acting as key transcriptional regulators of hundreds of genes. Several signaling pathways activated by diverse stimuli converge on NF-κB activation, resulting in a regulatory system characterized by high complexity. It is increasingly recognized that the number of components that impinges upon phenotypic outcomes of signal transduction pathways may be higher than those taken into consideration from canonical pathway representations. Scope of the present analysis is to provide a wider, systemic picture of the NF-κB signaling system. Data from different sources such as literature, functional enrichment web resources, protein-protein interaction and pathway databases have been gathered, curated, integrated and analyzed in order to reconstruct a single, comprehensive picture of the proteins that interact with, and participate to the NF-κB activation system. Such a reconstruction shows that the NF-κB interactome is substantially different in quantity and quality of components with respect to canonical representations. The analysis highlights that several neglected but topologically central proteins may play a role in the activation of NF-κB mediated responses. Moreover the interactome structure fits with the characteristics of a bow tie architecture. This interactome is intended as an open network resource available for further development, refinement and analysis.


Assuntos
NF-kappa B/metabolismo , Mapeamento de Interação de Proteínas/métodos , Transdução de Sinais , Humanos , Anotação de Sequência Molecular
16.
Biochem Biophys Res Commun ; 408(1): 65-70, 2011 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-21458417

RESUMO

Immunoproteasome has been associated to neurodegenerative and autoimmune diseases as a marker and regulator of inflammatory mechanisms. Its expression in the brain may occur upon neuroinflammation in different cell types and affect a variety of homeostatic and inflammatory pathways including the oxidized protein clearance and the self-antigen presentation. In the present study we investigated the immunoproteasome expression in hippocampi and cortex of patients affected by different histopathological forms of pharmaco-resistent mesial temporal lobe epilepsy. We identified a pathology-specific pattern of immunoproteasome expression, which could provide insight into the complex neuroinflammatory pathogenic components of this disease.


Assuntos
Cisteína Endopeptidases/metabolismo , Epilepsia do Lobo Temporal/imunologia , Hipocampo/imunologia , Complexo de Endopeptidases do Proteassoma/imunologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complexo de Endopeptidases do Proteassoma/metabolismo , Adulto Jovem
17.
PLoS One ; 5(8): e12037, 2010 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-20700462

RESUMO

BACKGROUND: Alzheimer's Disease (AD) is the most common neurodegenerative disease and the leading cause of dementia among senile subjects. It has been proposed that AD can be caused by defects in mitochondrial oxidative phosphorylation. Given the fundamental contribution of the mitochondrial genome (mtDNA) for the respiratory chain, there have been a number of studies investigating the association between mtDNA inherited variants and multifactorial diseases, however no general consensus has been reached yet on the correlation between mtDNA haplogroups and AD. METHODOLOGY/PRINCIPAL FINDINGS: We applied for the first time a high resolution analysis (sequencing of displacement loop and restriction analysis of specific markers in the coding region of mtDNA) to investigate the possible association between mtDNA-inherited sequence variation and AD in 936 AD patients and 776 cognitively assessed normal controls from central and northern Italy. Among over 40 mtDNA sub-haplogroups analysed, we found that sub-haplogroup H5 is a risk factor for AD (OR=1.85, 95% CI:1.04-3.23) in particular for females (OR=2.19, 95% CI:1.06-4.51) and independently from the APOE genotype. Multivariate logistic regression revealed an interaction between H5 and age. When the whole sample is considered, the H5a subgroup of molecules, harboring the 4336 transition in the tRNAGln gene, already associated to AD in early studies, was about threefold more represented in AD patients than in controls (2.0% vs 0.8%; p=0.031), and it might account for the increased frequency of H5 in AD patients (4.2% vs 2.3%). The complete re-sequencing of the 56 mtDNAs belonging to H5 revealed that AD patients showed a trend towards a higher number (p=0.052) of sporadic mutations in tRNA and rRNA genes when compared with controls. CONCLUSIONS: Our results indicate that high resolution analysis of inherited mtDNA sequence variation can help in identifying both ancient polymorphisms defining sub-haplogroups and the accumulation of sporadic mutations associated with complex traits such as AD.


Assuntos
Doença de Alzheimer/genética , DNA Mitocondrial/genética , Predisposição Genética para Doença , Haplótipos/genética , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Mutação , Filogenia , Polimorfismo Genético
18.
Biochem Biophys Res Commun ; 397(2): 301-6, 2010 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-20510670

RESUMO

Despite the central role of proteasomes in relevant physiological pathways and pathological processes, this topic is unexpectedly largely unexplored in human liver. Here we present data on the presence of proteasome and immunoproteasome in human livers from normal adults, fetuses and patients affected by major hepatic diseases such as cirrhosis and chronic active hepatitis. Immunohistochemistry for constitutive (alpha4 and beta1) and inducible (LMP2 and LMP7) proteasome subunits, and for the PA28alphabeta regulator, was performed in liver samples from 38 normal subjects, 6 fetuses, 2 pediatric cases, and 19 pathological cases (10 chronic active hepatitis and 9 cirrhosis). The immunohistochemical data have been validated and quantified by Western blotting analysis. The most striking result we found was the concomitant presence in hepatocyte cytoplasm of all healthy subjects, including the pediatric cases, of constitutive proteasome and immunoproteasome subunits, as well as PA28alphabeta. At variance, immunoproteasome was not present in hepatocytes from fetuses, while a strong cytoplasmic and nuclear positivity for LMP2 and LMP7 was found in pathological samples, directly correlated to the histopathological grade of inflammation. At variance from other organs such as the brain, immunoproteasome is present in livers from normal adult and pediatric cases, in apparent absence of pathological processes, suggesting the presence of a peculiar regulation of the proteasome/immunoproteasome system, likely related to the physiological stimuli derived from the gut microbiota after birth. Other inflammatory stimuli contribute in inducing high levels of immunoproteasome in pathological conditions, where its role deserve further attention.


Assuntos
Feto/enzimologia , Hepatite/enzimologia , Cirrose Hepática/enzimologia , Fígado/enzimologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Cisteína Endopeptidases/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Fígado/embriologia , Masculino , Pessoa de Meia-Idade , Complexos Multienzimáticos/metabolismo , Proteínas Musculares/metabolismo , Adulto Jovem
19.
PLoS One ; 5(2): e9287, 2010 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-20174631

RESUMO

BACKGROUND: Albeit several studies pointed out the pivotal role that CD4+T cells have in Multiple Sclerosis, the CD8+ T cells involvement in the pathology is still in its early phases of investigation. Proteasome degradation is the key step in the production of MHC class I-restricted epitopes and therefore its activity could be an important element in the activation and regulation of autoreactive CD8+ T cells in Multiple Sclerosis. METHODOLOGY/PRINCIPAL FINDINGS: Immunoproteasomes and PA28-alphabeta regulator are present in MS affected brain area and accumulated in plaques. They are expressed in cell types supposed to be involved in MS development such as neurons, endothelial cells, oligodendrocytes, macrophages/macroglia and lymphocytes. Furthermore, in a genetic study on 1262 Italian MS cases and 845 controls we observed that HLA-A*02+ female subjects carrying the immunoproteasome LMP2 codon 60HH variant have a reduced risk to develop MS. Accordingly, immunoproteasomes carrying the LMP2 60H allele produce in vitro a lower amount of the HLA-A*0201 restricted immunodominant epitope MBP(111-119). CONCLUSION/SIGNIFICANCE: The immunoproteasome LMP2 60HH variant reduces the risk to develop MS amongst Italian HLA-A*02+ females. We propose that such an effect is mediated by the altered proteasome-dependent production of a specific MBP epitope presented on the MHC class I. Our observations thereby support the hypothesis of an involvement of immunoproteasome in the MS pathogenesis.


Assuntos
Cisteína Endopeptidases/imunologia , Epitopos/imunologia , Antígenos HLA-A/imunologia , Esclerose Múltipla/imunologia , Adulto , Sequência de Aminoácidos , Encéfalo/metabolismo , Encéfalo/patologia , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Epitopos/metabolismo , Feminino , Frequência do Gene , Genótipo , Antígenos HLA-A/genética , Antígenos HLA-A/metabolismo , Antígeno HLA-A2 , Humanos , Imuno-Histoquímica , Itália , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Microglia/metabolismo , Microglia/patologia , Pessoa de Meia-Idade , Dados de Sequência Molecular , Esclerose Múltipla/genética , Esclerose Múltipla/metabolismo , Proteínas Musculares/metabolismo , Proteína Básica da Mielina/imunologia , Proteína Básica da Mielina/metabolismo , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Fatores de Risco , Fatores Sexuais
20.
CNS Drugs ; 24(2): 163-76, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20088621

RESUMO

Acetylcholinesterase inhibitors (AChEIs) have been used to improve cognitive status and disability in patients with mild to moderate Alzheimer's disease (AD). However, while the efficacy of AChEIs (i.e. how they act in randomized controlled trials) in this setting is widely accepted, their effectiveness (i.e. how they behave in the real world) remains controversial. To compare the effects of three AChEIs, donepezil (Aricept), galantamine (Reminyl) and rivastigmine (Exelon), in an Italian national, prospective, observational study representative of the 'real world' clinical practice of AChEI treatment for AD. 938 patients with mild to moderate AD collected within the framework of the Italian National Cronos Project (CP), involving several UVAs (AD Evaluation Units) spread over the entire national territory, who were receiving donepezil, galantamine or rivastigmine were followed for 36 weeks by measuring: (i) function, as determined by the Activities of Daily Living (ADL) and Instrumental Activities of Daily Living (IADL) scales; (ii) cognition, as measured by the Mini-Mental State Examination (MMSE) and the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog) [primary outcome measures]; and (iii) behaviour, as measured on the Neuropsychiatric Inventory (NPI) and Clinical Dementia Rating (CDR) scale. Moreover, all patients were genotyped for apolipoprotein E (apoE) genetic variants. No statistically significant improvement in the primary outcome measures (MMSE and ADAS-Cog) was observed with drug therapy at 36 weeks, at which point all groups had lost, on average, 1 point on the MMSE and gained 2-3 points on the ADAS-Cog scale compared with baseline. On the secondary outcome measures at week 36, all treatment groups showed a significant worsening on the ADL and IADL scales compared with baseline, while on the NPI scale there were no significant differences from baseline except for the galantamine-treated group which worsened significantly. Moreover, patients receiving galantamine worsened significantly compared with the donepezil-treated group on the IADL scale. ApoE epsilon4 allele did not influence the effect of drug therapy. Over a 36-week follow-up period, no significant difference in the effects of donepezil, galantamine and rivastigmine on a variety of functional and cognitive parameters was observed in a large number of apoE-genotyped patients with mild to moderate AD recruited within the framework of a national project representative of the scenario usually encountered in actual clinical practice in Italy. The limitations (possibility of administration of lower drug doses than are used in clinical trials, relatively short follow-up period and the lack of randomization) and strengths (large number of patients, concomitant observation of the three drugs and the number of parameters assessed, including apoE genotype) of the present study are acknowledged. Our type of naturalistic study should complement clinical trials because 'real world' practice operates in the face of the numerous variables (e.g. health status and co-morbidities) associated with a complex disease such as AD in elderly people.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/uso terapêutico , Galantamina/uso terapêutico , Indanos/uso terapêutico , Fenilcarbamatos/uso terapêutico , Piperidinas/uso terapêutico , Atividades Cotidianas , Idoso , Doença de Alzheimer/genética , Apolipoproteínas E/genética , Cognição/efeitos dos fármacos , Donepezila , Feminino , Variação Genética , Genótipo , Humanos , Itália , Masculino , Avaliação de Resultados em Cuidados de Saúde , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Rivastigmina , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
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