RESUMO
The gut microbiota has gained increasing attention in recent years due to its significant impact on colorectal cancer (CRC) development and progression. The recent detection of bacterial DNA load in plasma holds promise as a potential non-invasive approach for early cancer detection. The aim of this study was to examine the quantity of bacterial DNA present in the plasma of 50 patients who have CRC in comparison to 40 neoplastic disease-free patients, as well as to determine if there is a correlation between the amount of plasma bacterial DNA and various clinical parameters. Plasma bacterial DNA levels were found to be elevated in the CRC group compared to the control group. As it emerged from the logistic analysis (adjusted for age and gender), these levels were strongly associated with the risk of CRC (OR = 1.02, p < 0.001, 95% C.I.: 1.01-1.03). Moreover, an association was identified between a reduction in tumor mass and the highest tertile of plasma bacterial DNA. Our findings indicate that individuals with CRC displayed a higher plasma bacterial DNA load compared to healthy controls. This observation lends support to the theory of heightened bacterial migration from the gastrointestinal tract to the bloodstream in CRC. Furthermore, our results establish a link between this phenomenon and the size of the tumor mass.
RESUMO
Herpesviridae reactivation such as cytomegalovirus (CMV) has been described in severe COVID-19 (COronaVIrusDisease-2019). This study aimed to understand if CMV reactivation in older COVID-19 patients is associated with increased inflammation and in-hospital mortality. In an observational single-center cohort study, 156 geriatric COVID-19 patients were screened for CMV reactivation by RT-PCR. Participants underwent a comprehensive clinical investigation that included medical history, functional evaluation, laboratory tests and cytokine assays (TNF-α, IFN-α, IL-6, IL-10) at hospital admission. In 19 (12.2%) of 156 COVID-19 patients, CMV reactivation was detected. Multivariate Cox regression models showed that in-hospital mortality significantly increased among CMV positive patients younger than 87 years (HR: 9.94, 95% CI: 1.66-59.50). Other factors associated with in-hospital mortality were C-reactive protein (HR: 1.17, 95% CI: 1.05-1.30), neutrophil count (HR: 1.20, 95% CI: 1.01-1.42) and clinical frailty scale (HR:1.54, 95% CI: 1.04-2.28). In patients older than 87 years, neutrophil count (HR: 1.13, 95% CI: 1.05-1.21) and age (HR: 1.15, 95% CI: 1.01-1.31) were independently associated with in-hospital mortality. CMV reactivation was also correlated with increased IFN-α and TNF-α serum levels, but not with IL-6 and IL-10 serum changes. In conclusion, CMV reactivation was an independent risk factor for in-hospital mortality in COVID-19 patients younger than 87 years old, but not in nonagenarians.
Assuntos
COVID-19 , Infecções por Citomegalovirus , Idoso de 80 Anos ou mais , Humanos , Idoso , Citomegalovirus/fisiologia , Infecções por Citomegalovirus/complicações , Interleucina-10 , Estudos de Coortes , Interleucina-6 , Fator de Necrose Tumoral alfa , COVID-19/complicações , Ativação Viral , Estudos RetrospectivosRESUMO
Aging and age-related diseases have been linked to microbial dysbiosis with changes in blood bacterial DNA concentration. This condition may promote chronic low-grade inflammation, which can be further aggravated by antioxidant nutrient deficiency. Low plasma carotenoids are associated with an increased risk of inflammation and cellular damage and predict mortality. However, no evidence is yet available on the relationship between antioxidants and the blood bacterial DNA (BB-DNA). Therefore, this study aimed to compare BB-DNA from (a) GO (nonagenarian offspring), (b) age-matched controls (Randomly recruited Age-Stratified Individuals from the General population [RASIG]), and (c) spouses of GO (SGO) recruited in the MARK-AGE project, as well as to investigate the association between BB-DNA, behavior habits, Charlson Comorbidity Index (CCI), leucocyte subsets, and the circulating levels of some antioxidants and oxidative stress markers. BB-DNA was higher in RASIG than GO and SGO, whereas GO and SGO participants showed similar values. BB-DNA increased in smokers and males with CCIâ ≥â 2 compared with those with CCIâ ≤â 1 within RASIG. Moreover, BB-DNA was positively associated with lymphocyte, neutrophil, and monocyte counts, but not with self-reported dietary habits. Higher quartiles of BB-DNA were associated with low lutein and zeaxanthin and elevated malondialdehyde plasma concentrations in RASIG. BB-DNA was also positively correlated with nitric oxide levels. Herein, we provide evidence of a reduced BB-DNA in individuals from long-living families and their spouses, suggesting a decreased microbial dysbiosis and bacterial systemic translocation. BB-DNA was also associated with smoking, CCI, leukocyte subsets, and some redox biomarkers in older participants.
Assuntos
Disbiose , Nonagenários , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Antioxidantes/metabolismo , Biomarcadores , DNA Bacteriano , Inflamação , Oxirredução , Estresse OxidativoRESUMO
As we age, our body experiences chronic, systemic inflammation contributing to the morbidity and mortality of the elderly. The senescent immune system has been described to have a causal role in driving systemic aging and therefore may represent a key therapeutic target to prevent pathological consequences associated with aging and extend a healthy lifespan. Previous studies from our group associated a polymorphic haplotype variant in the BPIFB4 gene (LAV-BPIFB4) with exceptional longevity. Transfer of the LAV-BPIFB4 in preclinical models halted the progression of cardiovascular diseases (CVDs) and frailty by counterbalancing chronic inflammation. In the present study, we aimed to delineate the action of systemic adeno-associated viral vector-mediated LAV-BPIFB4 gene transfer (AAV-LAV-BPIFB4) on the deleterious age-related changes of the immune system and thereby the senescence-associated events occurring in C57BL/6J mice aged 26 months. Our in vivo data showed that 26-months-old mice had a higher frequency of CD45+SA-beta Gal+ immune cells in peripheral blood than young (4-months-old) C57BL/6J mice. Notably, AAV-LAV-BPIFB4 gene transfer in aged mice reduced the pool of peripheral immunosenescent cells that were shown to be enriched in the spleen. In addition, the proper tuning of the immune secretory phenotype (IL1ßlow, IL6low, IL10high) associated with a significant reduction in SA-beta Gal-positive area of aorta from AAV-LAV treated mice. At the functional level, the reduction of senescence-associated inflammation ensured sustained NAD+ levels in the plasma of AAV-LAV-BPIFB4 old mice by preventing the NADase CD38 increase in F4/80+ tissue-resident macrophages and Ly6Chigh pro-inflammatory monocytes of the spleen and bone marrow. Finally, to validate the clinical implication of our findings, we showed that Long-living-individuals (LLIs, >95 years), which delay CVDs onset, especially if LAV-carriers, were characterized by high NAD+ levels. In conclusion, the new senotherapeutic action of LAV-BPIFB4 may offer a valuable therapeutic tool to control aging and reduce the burden of its pathophysiological disorders, such as CVDs.
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Doenças Cardiovasculares , Terapia Genética , Sistema Imunitário , Peptídeos e Proteínas de Sinalização Intercelular , Longevidade , Animais , Doenças Cardiovasculares/terapia , Inflamação , Peptídeos e Proteínas de Sinalização Intercelular/genética , Macrófagos , Camundongos , Camundongos Endogâmicos C57BL , NAD , Fosfoproteínas/genéticaRESUMO
Microbial dysbiosis (MD) provokes gut barrier alterations and bacterial translocation in the bloodstream. The increased blood bacterial DNA (BB-DNA) may promote peripheral- and neuro-inflammation, contributing to cognitive impairment. MD also influences brain-derived neurotrophic factor (BDNF) production, whose alterations contribute to the etiopathogenesis of Alzheimer's disease (AD). The purpose of this study is to measure BB-DNA in healthy elderly controls (EC), and in patients with mild cognitive impairment (MCI) and AD to explore the effect on plasma BDNF levels (pBDNF), the inflammatory response, and the association with cognitive decline during a two-year follow-up. Baseline BB-DNA and pBDNF were significantly higher in MCI and AD than in EC. BB-DNA was positively correlated with pBDNF in AD, plasma Tumor necrosis factor-alpha (TNF-α), and Interleukin-10 (IL-10) levels in MCI. AD patients with BB-DNA values above the 50th percentile had lower baseline Mini-Mental State Examination (MMSE). After a two-year follow-up, AD patients with the highest BB-DNA tertile had a worse cognitive decline, while higher BB-DNA levels were associated with higher TNF-α and lower IL-10 in MCI. Our study demonstrates that, in early AD, the higher the BB-DNA levels, the higher the pBDNF levels, suggesting a defensive attempt; BB-DNA seems to play a role in the AD severity/progression; in MCI, higher BB-DNA may trigger an increased inflammatory response.
Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Idoso , Fator Neurotrófico Derivado do Encéfalo , Interleucina-10 , Doença de Alzheimer/diagnóstico , Fator de Necrose Tumoral alfa , Biomarcadores , DNARESUMO
Cadmium (Cd) accumulates with aging and is elevated in long-lived species. Metallothioneins (MTs), small cysteine-rich proteins involved in metal homeostasis and Cd detoxification, are known to be related to longevity. However, the relationship between Cd accumulation, the role of MTs, and aging is currently unclear. Specifically, we do not know if long-lived species evolved an efficient metal stress response by upregulating their MT levels to reduce the toxic effects of environmental pollutants, such as Cd, that accumulate over their longer life span. It is also unknown if the number of MT genes, their expression, or both protect the organisms from potentially damaging effects during aging. To address these questions, we reanalyzed several cross-species studies and obtained data on MT expression and Cd accumulation in long-lived mouse models. We confirmed a relationship between species maximum life span in captive mammals and their Cd content in liver and kidney. We found that although the number of MT genes does not affect longevity, gene expression and protein amount of specific MT paralogs are strongly related to life span in mammals. MT expression rather than gene number may influence the high Cd levels and longevity of some species. In support of this, we found that overexpression of MT-1 accelerated Cd accumulation in mice and that tissue Cd was higher in long-lived mouse strains with high MT expression. We conclude that long-lived species have evolved a more efficient stress response by upregulating the expression of MT genes in presence of Cd, which contributes to elevated tissue Cd levels.
Assuntos
Cádmio , Metalotioneína , Envelhecimento/genética , Animais , Cádmio/toxicidade , Rim , Fígado , Metalotioneína/genética , CamundongosRESUMO
The organotropism is the propensity of metastatic cancer cells to colonize preferably certain distant organs, resulting in a non-random distribution of metastases. In order to shed light on this behaviour, several studies were performed by the injection of human cancer cell lines into immunocompromised mouse models. However, the information about these experiments is spread in the literature. For each xenograft experiment reported in the literature, we annotated both the experimental conditions and outcomes, including details on inoculated human cell lines, mouse models, injection methods, sites of metastasis, organs not colonized, rate of metastasis, latency time, overall survival and the involved genes. We created MetaTropismDB, a freely available database collecting hand-curated data useful to highlight the mechanisms of organ-specific metastasis. Currently, it stores the results of 513 experiments in which injections of 219 human cell lines have been carried out in mouse models. Notably, 296 genes involved in organotropic metastases have been collected. This specialized database allows the researchers to compare the current results about organotropism and plan future experiments in order to identify which tumour molecular signatures establish if and where the metastasis will develop. Database URL: http://www.introni.it/Metastasis/metastasis.html.
Assuntos
Neoplasias , Animais , Linhagem Celular , Modelos Animais de Doenças , Humanos , CamundongosRESUMO
Aim: To evaluate CpG methylation of long interspersed nuclear elements 1 (LINE-1) and human endogenous retrovirus K (HERV-K) retroelements as potential prognostic biomarkers in cutaneous melanoma. Materials & methods: Methylation of HERV-K and LINE-1 retroelements was assessed in resected melanoma tissues from 82 patients ranging in age from 14 to 88 years. In addition, nevi from eight patients were included for comparison with nonmalignant melanocytic lesions. Results: Methylation levels were lower in melanomas than in nevi. HERV-K and LINE-1 methylation were decreased in melanoma patients with clinical parameters associated with adverse prognosis, while they were independent of age and gender. Hypomethylation of HERV-K (but not LINE-1) was an independent predictor of reduced disease-free survival. Conclusion: HERV-K hypomethylation can be a potential independent biomarker of melanoma recurrence.
Assuntos
Metilação de DNA , Elementos Nucleotídeos Longos e Dispersos , Melanoma/genética , Retroelementos , Neoplasias Cutâneas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ilhas de CpG , Intervalo Livre de Doença , Retrovirus Endógenos , Feminino , Humanos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Estadiamento de Neoplasias , Nevo/genética , Prognóstico , Neoplasias Cutâneas/patologia , Sequências Repetidas Terminais , Adulto JovemAssuntos
Nicotina , Doença Pulmonar Obstrutiva Crônica , Betacoronavirus , COVID-19 , Infecções por Coronavirus , Humanos , Pandemias , Pneumonia Viral , SARS-CoV-2 , Fumantes , FumarRESUMO
The higher death rate caused by COVID-19 in older people, especially those with comorbidities, is a challenge for biomedical aging research. Here we explore the idea that an exacerbated inflammatory response, in particular that mediated by IL-6, may drive the deleterious consequences of the infection. Data shows that other RNA viruses, such as influenza virus, can display enhanced replication efficiency in senescent cells, suggesting that the accumulation of senescent cells with aging and age-related diseases may play a role in this phenomenon. However, at present, we are completely unaware of the response to SARS-CoV and SARS-COV-2 occurring in senescent cells. We deem that this is a priority area of research because it could lead to the development of several therapeutic strategies based on senotherapeutics or prevent unsuccessful attempts. Two of these senotherapeutics, azithromycin and ruxolitinib, are currently undergoing testing for their efficacy in treating COVID-19. The potential of these strategies is not only for ameliorating the consequences of the current emergence of SARS-CoV-2, but also for the future emergence of new viruses or mutated ones for which we are completely unprepared and for which no vaccines are available.
Assuntos
Envelhecimento/imunologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/imunologia , Saúde Global/tendências , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/imunologia , Anti-Infecciosos/normas , Anti-Infecciosos/uso terapêutico , Azitromicina/uso terapêutico , COVID-19 , Senescência Celular/imunologia , Humanos , Interleucina-6/imunologia , Nitrilas , Pandemias , Pirazóis/uso terapêutico , PirimidinasRESUMO
Epidemiologic studies suggest that exposure to Cd is related to a multitude of age-related diseases. There is evidence that Cd toxicity emerges from an interference with Zn metabolism as they compete for the same binding sites of ligands. The most responsive proteins to Cd exposure are the metal-binding proteins termed metallothioneins (MTs), which display a much greater affinity for Cd than for Zn. Most studies have considered the effect of Zn on the accumulation of exogenous Cd and tissue damage, whereas observational studies have addressed the association between Zn intake and Cd levels in body fluids. However, it has not been addressed whether supplemental Zn can lower Cd levels in organs of healthy aged animals without affecting Cu stores, a question more pertinent to human aging. We therefore aimed to investigate the effect of Zn supplementation on Cd levels in liver and kidney of aged MT transgenic mice (MT1-tg) overexpressing MT1 at levels more comparable to those observed in humans than non-transgenic mice. We found a >30% reduction of kidney and liver Cd levels in Zn supplemented MT1-tg mice compared to non-supplemented controls, independently of the dose of Zn, without a significant reduction of Cu. Our data support the idea of a causal and inverse relationship between Zn intake and Cd content in organs of aged MT1-tg mice as suggested by observational studies in humans. Our work provides the rationale for interventional studies to address the effects of Zn supplementation on Cd burden in elderly people.
Assuntos
Cádmio/química , Metalotioneína/metabolismo , Zinco/uso terapêutico , Idoso , Animais , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Zinco/química , Zinco/farmacologiaRESUMO
The reactivation of senescence in cancer and the subsequent clearance of senescent cells are suggested as therapeutic intervention in the eradication of cancer. Several natural compounds that activate Nrf2 (nuclear factor erythroid-derived 2-related factor 2) pathway, which is involved in complex cytoprotective responses, have been paradoxically shown to induce cell death or senescence in cancer. Promoting the cytoprotective Nrf2 pathway may be desirable for chemoprevention, but it might be detrimental in later stages and advanced cancers. However, senolytic activity shown by some Nrf2-activating compounds could be used to target senescent cancer cells (particularly in aged immune-depressed organisms) that escape immunosurveillance. We herein describe in vitro and in vivo effects of fifteen Nrf2-interacting natural compounds (tocotrienols, curcumin, epigallocatechin gallate, quercetin, genistein, resveratrol, silybin, phenethyl isothiocyanate, sulforaphane, triptolide, allicin, berberine, piperlongumine, fisetin, and phloretin) on cellular senescence and discuss their use in adjuvant cancer therapy. In light of available literature, it can be concluded that the meaning and the potential of adjuvant therapy with natural compounds in humans remain unclear, also taking into account the existence of few clinical trials mostly characterized by uncertain results. Further studies are needed to investigate the therapeutic potential of those compounds that display senolytic activity.
Assuntos
Senescência Celular/fisiologia , Fator 2 Relacionado a NF-E2/metabolismo , Neoplasias/metabolismo , Animais , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Modelos MolecularesRESUMO
Metallothionein (MT) family are cysteine-rich proteins that regulate zinc (Zn) homeostasis and protect against oxidative damage. Studies in transgenic mice have shown that MT favorably influence longevity, although their role in human aging is not completely understood. Within the European multicenter study MARK-AGE, we analyzed MT induction after Zn treatment in peripheral blood mononuclear cells (PBMCs) and its relation with redox biomarkers in 2,936 age-stratified subjects (35-75 years) including the general population (RASIG), centenarian offspring (GO), and their spouses (SGO). We found that the lymphocyte capability to induce MT in response to Zn is not affected by aging. However, GO participants showed lower Zn-induced MT and increased basal expression of MT1A, MT1X, and ZnT-1 genes than RASIG subjects. Moreover, Zn-induced MT levels were found to be inversely related with oxidative stress markers (plasma protein carbonyls, 3-nitrotyrosine, and malondialdehyde) in the whole population, but not in GO subjects. In conclusion, our results support the hypothesis that the response to Zn is attenuated in PBMCs of centenarian offspring compared to the general population as a consequence of a tighter control of Zn homeostasis which is likely to provide them constant protection against stress stimuli over the whole lifespan.
Assuntos
Biomarcadores/metabolismo , Leucócitos Mononucleares/metabolismo , Metalotioneína/metabolismo , Zinco/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas de Cultura de Células , Estudos Transversais , Europa (Continente) , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , RNA/metabolismo , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Endogenous retroelements (ERs) represent nearly half of the human genome. Considered up to recent years as "functionless" DNA sequences, they are now known to be involved in important cellular functions such as stress response and generation of non coding regulatory RNAs. Moreover, an increasing amount of data supports the idea of ERs as key players in cellular senescence and in different senescence-related pathogenic cellular processes, including those leading to inflammation, cancer and major age-related multifactorial diseases. The involvement of ERs in these biological mechanisms can suggest new therapeutic strategies in neoplasms, inflammatory/autoimmune diseases and in different age-related pathologies, such as macular degeneration, diabetes, cardiovascular diseases and major age-related neurodegenerative disorders. The therapeutic approaches which can be suggested range from a set of well-known, common drugs that have been shown to modulate ERs activity, to immune therapy against ER-derived tumor antigens, to more challenging strategies such as those based on anti-ERs RNA interference.
Assuntos
Envelhecimento/patologia , Senescência Celular/efeitos dos fármacos , Retroelementos , Envelhecimento/efeitos dos fármacos , Envelhecimento/genética , Animais , Doenças Autoimunes/genética , Predisposição Genética para Doença , Humanos , Degeneração Macular/genética , Neoplasias/genética , Doenças Neurodegenerativas/genética , Retroelementos/efeitos dos fármacosRESUMO
The possibility to target cellular senescence with natural bioactive substances open interesting therapeutic perspective in cancer and aging. Engaging senescence response is suggested as a key component for therapeutic intervention in the eradication of cancer. At the same time, delaying senescence or even promote death of accumulating apoptosis-resistant senescent cells is proposed as a strategy to prevent age related diseases. Although these two desired outcome present an intrinsic dichotomy, there are examples of promising natural compounds that appear to satisfy all the requirements to develop senescence- targeted health promoting nutraceuticals. Tocotrienols (T3s) and quercetin (QUE), albeit belonging to different phytochemical classes, display similar and promising effects "in vitro" when tested in normal and cancer cells. Both compounds have been shown to induce senescence and promote apoptosis in a multitude of cancer lines. Conversely, they display senescence delaying activity in primary cells and rejuvenating effects in senescent cells. More recently, QUE has been shown to display senolytic effects in some primary senescent cells, likely as a consequence of its inhibitory effects on specific anti-apoptotic genes (i.e. PI3K and other kinases). Senolytic activity has not been tested for T3s but part of metabolic and apoptotic pathways affected by these compounds in cancer cells overlap with those of QUE. This suggests that the rejuvenating effects of T3s and QUE on pre-senescent and senescent primary cells might be the net results of a senolytic activity on senescent cells and a selective survival of a sub-population of non-senescent cells in the culture. The meaning of this hypothesis in the context of adjuvant therapy of cancer and preventive anti-aging strategies with QUE or T3s is discussed.
Assuntos
Senescência Celular/efeitos dos fármacos , Quercetina/farmacologia , Tocotrienóis/farmacologia , Animais , Apoptose , Linhagem Celular Tumoral , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Neoplasias/tratamento farmacológico , Compostos Fitoquímicos/farmacologiaRESUMO
Zinc dyshomeostasis may lead to an augmented production of proinflammatory cytokines promoting chronic inflammation and increasing the susceptibility to age-related diseases. Several studies suggest that the zinc transporter protein ZIP2 may play a relevant role in the immune system especially during zinc deficiency, while a polymorphism on the coding region of ZIP2 gene (Gln/Arg/Leu) has been associated with severe carotid artery disease. The aim of this study is to investigate the role of ZIP2 SNP on zinc and inflammatory status in 1090 elderly healthy free-living subjects enrolled in the ZincAge project and to assess the effect of zinc supplementation on zinc status, inflammatory mediators, and zinc transporter expression depending on ZIP2 genotype. ZIP2 Leu- (Arg43Arg) carriers showed enhanced IL-6, TNF-α, and RANTES plasma levels associated with decreased free cytosolic zinc in PBMCs and an upregulation of zinc transporters ZIP2, ZIP8, and Znt1. Moreover, Leu- subjects displayed significant decrement of inflammatory mediators such as MCP-1, TNF-α, and RANTES following zinc supplementation. In summary, this investigation provides new evidence on the effect of ZIP2 Gln/Arg/Leu polymorphism on proinflammatory mediators and zinc homeostasis in elderly population with a more pronounced anti-inflammatory effect of zinc supplementation in subjects carrying ZIP2 Leu- (Arg43Arg) genotype. These novel findings could be useful in identifying elderly subjects who may benefit of zinc intervention to decrease the inflammatory status and to prevent or delay the development of age-related diseases.
Assuntos
Envelhecimento/genética , Proteínas de Transporte de Cátions/genética , Inflamação/sangue , Zinco/sangue , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Envelhecimento/patologia , Proteínas de Transporte de Cátions/metabolismo , Quimiocina CCL5/sangue , Suplementos Nutricionais , Feminino , Genótipo , Homeostase , Humanos , Sistema Imunitário/metabolismo , Inflamação/dietoterapia , Inflamação/genética , Inflamação/patologia , Interleucina-6/sangue , Leucócitos Mononucleares , Masculino , Polimorfismo de Nucleotídeo Único , Fator de Necrose Tumoral alfa/sangue , Zinco/deficiência , Zinco/farmacologia , Zinco/uso terapêuticoRESUMO
Cellular senescence is considered an important mechanism to prevent malignant transformation of potentially mutated cells but, persistence of senescent cells within tissues alters microenvironment in ways that can promote cancer and aging phenotype thus underlining pathophysiologic processes of different age-related diseases. Coincident with this increased knowledge, understanding and finding modulators of the dynamics that control senescent-cell formation, fate and subsequent effect on tissue function has gained critical interest in experimental gerontology and cancer research. The purpose of this review is to discuss the evidence that various dietary bioactive compounds can modulate cellular senescence in vitro and to summarize findings and mechanisms that might be useful for the development of health-promoting nutraceuticals. An overview of cellular senescence and its impact in aging and cancer is described along with the strategies and pathways that are currently being investigated to target cellular senescence. Particular emphasis is given to the mechanisms by which bioactive dietary factors (i.e., most polyphenols) can delay or induce cellular senescence in vitro and how this knowledge could be used to explain the opposite effects shown in cancer lines and primary cells by some of these compounds. In addition, the problems to translate findings from modulation of cellular senescence in vitro into experimental treatments or clinical trials able to prevent or counteract age-related diseases are briefly described. The information herein provided might be useful to design further research in the field as well as to develop new nutraceuticals to be tested in experimental models and clinical trials.
Assuntos
Envelhecimento , Senescência Celular/efeitos dos fármacos , Dieta , Neoplasias , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Humanos , Neoplasias/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Polifenóis/uso terapêuticoRESUMO
Recent longitudinal studies in dietary daily intake in human centenarians have shown that a satisfactory content of some micronutrients within the cells maintain several immune functions, a low grade of inflammation and preserve antioxidant activity. Micronutrients (zinc, copper, selenium) play a pivotal role in maintaining and reinforcing the performances of the immune and antioxidant systems as well as in affecting the complex network of the genes (nutrigenomic) with anti- and pro-inflammatory tasks. Genes of pro- and anti-inflammatory cytokines and some key regulators of trace elements homeostasis, such as Metallothioneins (MT), are involved in the susceptibility to major geriatric disease/disorders. Moreover, the genetic inter-individual variability may affect the nutrients' absorption (nutrigenetic) with altered effects on inflammatory/immune response and antioxidant activity. The interaction between genetic factors and micronutrients (nutrigenomic and nutrigenetic approaches) may influence ageing and longevity because the micronutrients may become also toxic. This review reports the micronutrient-gene interactions in ageing and their impact on the healthy state with a focus on the method of protein-metal speciation analysis. The association between micronutrient-gene interactions and the protein-metal speciation analysis can give a complete picture for a personalized nutrient supplementation or chelation in order to reach healthy ageing and longevity.
Assuntos
Envelhecimento , Antioxidantes/química , Inflamação/fisiopatologia , Micronutrientes/química , Idoso , Idoso de 80 Anos ou mais , Quelantes/química , Cobre/sangue , Cobre/química , Cobre/deficiência , Cobre/toxicidade , Suplementos Nutricionais , Humanos , Sistema Imunitário , Inflamação/genética , Longevidade/fisiologia , Nutrigenômica , Selênio/sangue , Selênio/deficiência , Selênio/toxicidade , Zinco/sangue , Zinco/deficiência , Zinco/toxicidadeRESUMO
In ageing, the accumulation of damaged molecules provoked by oxidative stress and inflammation contributes to altered gene expressions and cellular dysfunction. The antioxidant system is crucial in order to prevent damage to intracellular molecules including DNA and, consequently, to avoid cellular dysfunction or neoplastic transformation. However, during serious DNA damage, the cells can activate a response characterized by cell cycle arrest and production of factors (mainly chemokines and cytokines) named "senescent associated secretory phenotype" (SASP) with the putative function to attract immune cells involved in the clearance of the senescent cells. This phenomenon named "cellular senescence" is, by one side, an important tumor suppressive mechanism but, on the other side, it contributes to impair tissue regenerative capacity and to possible transformation of neighbouring cells to cancer cells if a rapid clearance of the senescent cell doesn't occur. Therefore, preventing DNA damage via an optimal intracellular antioxidant defence is the key to reduce risk of cancer while keeping senescent changes at minimum. Zinc-bound Metallothioneins (MT), could play a key role in this prevention because they are antioxidant proteins and release zinc ions for several proteins and enzymes involved in antioxidant and DNA-repair responses. Reduced MT expression and intracellular zinc occur in some models of senescent cells. This process is of relevance since zinc ions released from MT could be implicated in the modulation of SASP. In chronic inflammation, such as in ageing, the dysfunction in zinc release from MT occurs, suggesting a potential contribution to the onset of senescent cells. Hence, MT could be directly or indirectly involved in the modulation of cellular senescent state and might represent a possible therapeutic target against the accumulation of dysfunctional senescent cells.