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1.
Dietary macronutrient composition influences both hepatic function and aging. Previous work suggested that longevity and hepatic gene expression levels were highly responsive to dietary protein, but almost unaffected by other macronutrients. In contrast, we found expression of 4005, 4232, and 4292 genes in the livers of mice were significantly associated with changes in dietary protein (5%–30%), fat (20%–60%), and carbohydrate (10%–75%), respectively. More genes in aging‐related pathways (notably mTOR, IGF‐1, and NF‐kappaB) had significant correlations with dietary fat intake than protein and carbohydrate intake, and the pattern of gene expression changes in relation to dietary fat intake was in the opposite direction to the effect of graded levels of caloric restriction consistent with dietary fat having a negative impact on aging. We found 732, 808, and 995 serum metabolites were significantly correlated with dietary protein (5%–30%), fat (8.3%–80%), and carbohydrate (10%–80%) contents, respectively. Metabolomics pathway analysis revealed sphingosine‐1‐phosphate signaling was the significantly affected pathway by dietary fat content which has also been identified as significant changed metabolic pathway in the previous caloric restriction study. Our results suggest dietary fat has major impact on aging‐related gene and metabolic pathways compared with other macronutrients.  相似文献   

2.
Although the adverse effects of maternal aging on reproductive outcomes have been investigated widely, there is no consensus on the impact of paternal age. Therefore, we investigated the effect of paternal age on reproductive outcomes in a retrospective analysis of 9,991 in vitro fertilization (IVF) cycles performed at the Reproductive Medicine Center of the Third Affiliated Hospital of Guangzhou Medical University (China) between January 2007 and October 2013. Samples were grouped according to maternal age [<30 (3,327 cycles), 30–34 (4,587 cycles), and 35–38 (2,077 cycles)] and then subgrouped according to paternal age (<30, 30–32, 33–35, 36–38, 39–41, and ≥42). The groups did not differ in terms of fertilization rate, numbers of viable and high-quality embryos and miscarriage rate when controlling maternal age (P >0.05). Chi-squared analysis revealed that there were no differences in implantation and pregnancy rates among the different paternal age groups when maternal age was <30 and 35–38 years (P >0.05). However, implantation and pregnancy rates decreased with paternal age in the 31–34 y maternal age group (P <0.05). Our study indicates that paternal age has no impact on fertilization rate, embryo quality at the cleavage stage and miscarriage rate. For the 30–34 y maternal age group, the implantation rate decreased with increased paternal age, with the pregnancy rate in this group being significantly higher in the paternal <30 y and 30–32 y age groups, compared with those in the 36–38 y and 39–41 y groups.  相似文献   

3.
Milk Fat Globule – EGF – factor VIII (MFGE8), also called lactadherin, is a secreted protein, which binds extracellularly to phosphatidylserine and to αvβ3 and αvβ5 integrins. On human and mouse cells expressing these integrins, such as endothelial cells, phagocytes and some tumors, MFGE8/lactadherin has been shown to promote survival, epithelial to mesenchymal transition and phagocytosis. A protumoral function of MFGE8 has consequently been documented for a few types of human cancers, including melanoma, a subtype of breast cancers, and bladder carcinoma. Inhibiting the functions of MFGE8 could thus represent a new type of therapy for human cancers. Here, we show by immunohistochemistry on a collection of human ovarian cancers that MFGE8 is overexpressed in 45% of these tumors, and we confirm that it is specifically overexpressed in the triple-negative subtype of human breast cancers. We have established new in vitro assays to measure the effect of MFGE8 on survival, adhesion and migration of human ovarian and triple-negative breast cancer cell lines. Using these assays, we could identify new MFGE8-specific monoclonal antibodies, which efficiently blocked these three tumor-promoting effects of MFGE8. Our results suggest future use of MFGE8-blocking antibodies as new anti-cancer therapeutics in subgroups of ovarian carcinoma, and triple-negative breast carcinoma patients.  相似文献   

4.
5.

Background

Strong evidence supports that living in disadvantaged neighborhoods has direct unfavorable impact on mental and physical health. However, whether it also has direct impact on cellular health is largely unknown. Thus we examined whether neighborhood quality was associated with leukocyte telomere length, an indicator of cellular aging.

Methods

In May 2014, we extracted and analyzed baseline data from the Netherlands Study of Depression and Anxiety (NESDA), a large epidemiological study of individuals age between 18–65 years (n=2902). Telomere length was determined using quantitative polymerase chain reaction. Neighborhood quality was assessed using modified measures of perceived neighborhood disorder, fear of crime, and noise. We used multivariable linear regression models to examine association between perceived neighborhood quality and telomere length with comprehensive adjustment for individual and community characteristics related to socioeconomic and demographic status, urbanization level, mental and physical health, and lifestyle.

Results

Compared to individuals who reported good neighborhood quality, the mean telomere length of those who reported moderate neighborhood quality was approximately 69 base pair shorter (β =-69.33, 95% CI: -119.49, -19.17, p= 0.007), and that of those who reported poor neighborhood quality were 174 base pair shorter (β =-173.80, 95% CI: -298.80, -49.01, p=0.006). For illustrative purposes, one could extrapolate these outcomes to 8.7 and 11.9 years in chronological age, respectively.

Conclusion

We have established an association between perceived neighborhood quality and cellular aging over and above a range of individual attributes. Biological aging processes may be impacted by socioeconomic milieu.  相似文献   

6.
WRAP53 protein controls intracellular trafficking of DNA repair proteins, the telomerase enzyme, and splicing factors. Functional loss of the protein has been linked to carcinogenesis, premature aging and neurodegeneration. The aim of this study was to investigate the prognostic significance of WRAP53 protein expression in breast cancer. A tissue microarray was constructed from primary breast tumors and immunostained by a polyclonal WRAP53 antibody to assess the protein expression pattern. Two different patient cohorts with long term follow-up were studied; a test- and a validation set of 154 and 668 breast tumor samples respectively. Breast cancer patients with tumor cells lacking the expression of WRAP53 in the nucleus had a significantly poorer outcome compared to patients with tumor cells expressing this protein in the nuclei (HR = 1.95, 95%CI = 1.09–3.51, p = 0.025). Nuclear localization of WRAP53 was further shown to be an independent marker of prognosis in multivariate analysis (HR = 2.57, 95%CI = 1.27–5.19, p = 0.008), and also significantly associated with better outcome in patients with TP53 mutation. Here we show that the sub-cellular localization of the WRAP53 protein has a significant impact on breast cancer survival, and thus has a potential as a clinical marker in diagnostics and treatment.  相似文献   

7.
Normal aging is associated with cognitive decline. Evidence indicates that large-scale brain networks are affected by aging; however, it has not been established whether aging has equivalent effects on specific large-scale networks. In the present study, 40 healthy subjects including 22 older (aged 60–80 years) and 18 younger (aged 22–33 years) adults underwent resting-state functional MRI scanning. Four canonical resting-state networks, including the default mode network (DMN), executive control network (ECN), dorsal attention network (DAN) and salience network, were extracted, and the functional connectivities in these canonical networks were compared between the younger and older groups. We found distinct, disruptive alterations present in the large-scale aging-related resting brain networks: the ECN was affected the most, followed by the DAN. However, the DMN and salience networks showed limited functional connectivity disruption. The visual network served as a control and was similarly preserved in both groups. Our findings suggest that the aged brain is characterized by selective vulnerability in large-scale brain networks. These results could help improve our understanding of the mechanism of degeneration in the aging brain. Additional work is warranted to determine whether selective alterations in the intrinsic networks are related to impairments in behavioral performance.  相似文献   

8.
Aneuploidy, defined as an abnormal number of chromosomes, is a hallmark of cancer. Paradoxically, aneuploidy generally has a negative impact on cell growth and fitness in nontransformed cells. In this work, we review recent progress in identifying how aneuploidy leads to genomic and chromosomal instability, how cells can adapt to the deleterious effects of aneuploidy, and how aneuploidy contributes to tumorigenesis in different genetic contexts. Finally, we also discuss how aneuploidy might be a target for anticancer therapies.As Horace famously wrote in his Odes, the “golden mean” is the secret to a happy, balanced life. Recent work, reviewed here, emphasizes the importance of this kind of balance for the genetics of human cells.Maintaining a stable genome is critical for the preservation of genetic information during the life span of an organism. Despite mechanisms designed to ensure a diploid karyotype, errors can and do occur during chromosome segregation that result in the gain and loss of whole chromosomes. In vitro estimates suggest that normal, diploid cells missegregate a chromosome once every 100 cell divisions (Thompson and Compton 2008). The in vivo rate of chromosome missegregation is unknown, but could vary between different cell types. Even if the rate is low, an abnormal number of chromosomes, or aneuploidy, could have a significant impact on normal cell physiology, as well as tumorigenesis.Aneuploidy, at the level of the organism, is detrimental and generally incompatible with life. In humans, only three aneuploidies—trisomy 13, 18, and 21—are viable, and only trisomy 21 is compatible with a life span beyond infancy (Hassold et al. 2007). Despite the deleterious consequences of aneuploidy in normal physiological contexts, an abnormal number of chromosomes is one of the hallmarks of cancer cells. Aneuploidy is found in ∼90% of solid tumors and >50% of blood cancers (Beroukhim et al. 2010; Mitelman et al. 2013). Whether aneuploidy is a cause or consequence of cell transformation is a frequent topic of debate. The challenge for establishing a causal relationship stems from the complexity of cancer cells, in which numerical chromosome abnormalities are rarely found in isolation but are usually accompanied by other genomic alterations, such as point mutations, translocations, and microsatellite instability. This complexity makes it difficult to define the initiating event(s) in tumorigenesis.This review focuses on whole-chromosome aneuploidy, although it has been shown that the gain and loss of chromosome arms is also a common occurrence in cancer cells (Beroukhim et al. 2010; Mitelman et al. 2013). We review the molecular pathways leading to aneuploidy, the effects of aneuploidy on cellular physiology, and the links between aneuploidy and tumorigenesis. Finally, we also explore the exciting concept of targeting aneuploidy as a novel therapeutic approach in treating cancer.  相似文献   

9.
10.
The cellular protein quality control machinery is important for preventing protein misfolding and aggregation. Declining protein homeostasis (proteostasis) is believed to play a crucial role in age‐related neurodegenerative disorders. However, how neuronal proteostasis capacity changes in different diseases is not yet sufficiently understood, and progress in this area has been hampered by the lack of tools to monitor proteostasis in mammalian models. Here, we have developed reporter mice for in vivo analysis of neuronal proteostasis. The mice express EGFP‐fused firefly luciferase (Fluc‐EGFP), a conformationally unstable protein that requires chaperones for proper folding, and that reacts to proteotoxic stress by formation of intracellular Fluc‐EGFP foci and by reduced luciferase activity. Using these mice, we provide evidence for proteostasis decline in the aging brain. Moreover, we find a marked reaction of the Fluc‐EGFP sensor in a mouse model of tauopathy, but not in mouse models of Huntington’s disease. Mechanistic investigations in primary neuronal cultures demonstrate that different types of protein aggregates have distinct effects on the cellular protein quality control. Thus, Fluc‐EGFP reporter mice enable new insights into proteostasis alterations in different diseases.  相似文献   

11.
12.

Background

Shift work has been associated with adverse health effects by disturbing circadian rhythms. However,its potential long-term health effects and the persistent effects after leaving shifts have not been well established.

Methods and Results

We studied 26,463 workers from Tongji-Dongfeng Cohort in China. All the participants are retired employees of Dongfeng Motor Company. Information on demographics, occupational history and medical history were gathered through questionnaires. After adjusting potential confounders in the logistic regression models, shift work was associated with poor sleeping quality, diabetes and hypertension independently. We observed significant effects of shift work on poor sleeping quality, diabetes and hypertension; the ORs (95%CI) are 1.18 (1.09–1.27), 1.10 (1.03–1.17) and 1.05 (1.01–1.09) respectively. In the further analysis, we found elevated ORs (95%CI) for participants with poor sleeping quality, the ORs (95%CI) are 1.34 (1.08–1.60), 1.13 (1.05–1.21), 1.05 (1.03–1.07) and 1.05 (1.01–1.09) for 1–4, 5–9, 10–19, ≥20 years of shift work respectively. However, with the extension of leaving shift work duration, the effects of shift work on sleep quality gradually reduced.

Conclusions

Shift work may be an independent risk factor for sleeping quality, diabetes and hypertension even in retired workers. Applicable intervention strategies are needed for prevention of sleep loss, diabetes, and hypertension for shift workers.  相似文献   

13.
The chaperone-mediated sequestration of misfolded proteins into specialized quality control compartments represents an important strategy for maintaining protein homeostasis in response to stress. However, precisely how this process is controlled in time and subcellular space and integrated with the cell''s protein refolding and degradation pathways remains unclear. We set out to understand how aggregated proteins are managed during infection-related development by a globally devastating plant pathogenic fungus and to determine how impaired protein quality control impacts cellular differentiation and pathogenesis in this system. Here we show that in the absence of Hsp104 disaggregase activity, aggregated proteins are spatially sequestered into quality control compartments within conidia, but not within terminally differentiated infection cells, and thus spatial protein quality control is cell type–dependent. We demonstrate that impaired aggregate resolution results in a short-term developmental penalty but has no significant impact upon appressorium function. Finally, we show that, somewhat unexpectedly, the autophagy machinery is necessary for the normal formation and compartmentalization of protein aggregates. Taken together, our findings provide important new insight into spatial protein quality control during the process of terminal cellular differentiation by a globally important model eukaryote and reveal a new level of interplay between major proteostasis pathways.  相似文献   

14.
Background and Aims Reactive oxygen species (ROS) and reactive nitrogen species (RNS), such as nitric oxide (NO), play crucial roles in the signal transduction pathways that regulate plant growth, development and defence responses, providing a nexus of reduction/oxidation (redox) control that impacts on nearly every aspect of plant biology. Here we summarize current knowledge and concepts that lay the foundations of a new vision for ROS/RNS functions – particularly through signalling hubs – for the next decade.Scope Plants have mastered the art of redox control using ROS and RNS as secondary messengers to regulate a diverse range of protein functions through redox-based, post-translational modifications that act as regulators of molecular master-switches. Much current focus concerns the impact of this regulation on local and systemic signalling pathways, as well as understanding how such reactive molecules can be effectively used in the control of plant growth and stress responses.Conclusions The spectre of oxidative stress still overshadows much of our current philosophy and understanding of ROS and RNS functions. While many questions remain to be addressed – for example regarding inter-organellar regulation and communication, the control of hypoxia and how ROS/RNS signalling is used in plant cells, not only to trigger acclimation responses but also to create molecular memories of stress – it is clear that ROS and RNS function as vital signals of living cells.  相似文献   

15.
Numerous studies have examined the empirical evidence concerning the influence of demographic and socio-economic factors influencing child immunization, but no documentation is available which shows the actual impact of antenatal care (ANC) visits on subsequent child immunization. Therefore, this paper aims to examine the net impact of ANC visits on subsequent utilization of child immunization after removing the presence of selection bias. Nationwide data from India’s latest National Family Health Survey conducted during 2005–06 is used for the present study. The analysis has been carried out in the two separate models, in the first model 1–2 ANC visit and in the second model three or more ANC visits has been compared with no visit. We have used propensity score matching method with a counterfactual model that assesses the actual ANC visits effect on treated (ANC visits) and untreated groups (no ANC visit), and have employed Mantel-Haenszel bounds to examine whether result would be free from hidden bias or not. Using matched sample analysis result shows that child immunization among the groups of women who have completed 1–2 ANC visits and those who had more than two visits was about 13 percent and 19 percent respectively, higher than the group of women who have not made any ANC visit. Findings of nearest neighbor matching with replacement method, which completely eliminated the bias, indicate that selection bias present in data set leads to overestimates the positive effects of ANC visits on child immunization. Result based on Mantel-Haenszel bounds method suggest that if around 19 percent bias would be involved in the result then also we could observe the true positive effect of 1–2 ANC visits on child immunization. This also indicates that antenatal clinics are the conventional platforms for educating pregnant women on the benefits of child immunization.  相似文献   

16.
Aging is commonly described as being a continuous process affecting progressively organisms as time passes. This process results in a progressive decrease in individuals fitness through a wide range of both organismal–decreased motor activity, fertility, resistance to stress–and molecular phenotypes–decreased protein and energy homeostasis, impairment of insulin signaling. In the past 20 years, numerous genes have been identified as playing a major role in the aging process, yet little is known about the events leading to that loss of fitness. We recently described an event characterized by a dramatic increase of intestinal permeability to a blue food dye in aging flies committed to die within a few days. Importantly, flies showing this so called ‘Smurf’ phenotype are the only ones, among a population, to show various age-related changes and exhibit a high-risk of impending death whatever their chronological age. Thus, these observations suggest that instead of being one continuous phenomenon, aging may be a discontinuous process well described by at least two distinguishable phases. In this paper we addressed this hypothesis by implementing a new 2 Phases of Aging mathematiCal model (2PAC model) to simulate longevity curves based on the simple hypothesis of two consecutive phases of lifetime presenting different properties. We first present a unique equation for each phase and discuss the biological significance of the 3 associated parameters. Then we evaluate the influence of each parameter on the shape of survival curves. Overall, this new mathematical model, based on simple biological observations, is able to reproduce many experimental longevity curves, supporting the existence of 2 phases of aging exhibiting specific properties and separated by a dramatic transition that remains to be characterized. Moreover, it indicates that Smurf survival can be approximated by one single constant parameter for a broad range of genotypes that we have tested under our environmental conditions.  相似文献   

17.
There are numerous human diseases that are associated with protein misfolding and the formation of toxic protein aggregates. Activating the heat shock response (HSR) – and thus generally restoring the disturbed protein homeostasis associated with such diseases – has often been suggested as a therapeutic strategy. However, most data on activating the HSR or its downstream targets in mouse models of diseases associated with aggregate formation have been rather disappointing. The human chaperonome consists of many more heat shock proteins (HSPs) that are not regulated by the HSR, however, and researchers are now focusing on these as potential therapeutic targets. In this Review, we summarize the existing literature on a set of aggregation diseases and propose that each of them can be characterized or ‘barcoded’ by a different set of HSPs that can rescue specific types of aggregation. Some of these ‘non-canonical’ HSPs have demonstrated effectiveness in vivo, in mouse models of protein-aggregation disease. Interestingly, several of these HSPs also cause diseases when mutated – so-called chaperonopathies – which are also discussed in this Review.KEY WORDS: Chaperonopathies, Heat shock protein, Protein-aggregation diseases  相似文献   

18.
Chaperones and other quality control machinery guard proteins from inappropriate aggregation, which is a hallmark of neurodegenerative diseases. However, how the systems that regulate the “foldedness” of the proteome remain buffered under stress conditions and in different cellular compartments remains incompletely understood. In this study, we applied a FRET-based strategy to explore how well quality control machinery protects against the misfolding and aggregation of “bait” biosensor proteins, made from the prokaryotic ribonuclease barnase, in the nucleus and cytosol of human embryonic kidney 293T cells. We found that those barnase biosensors were prone to misfolding, were less engaged by quality control machinery, and more prone to inappropriate aggregation in the nucleus as compared with the cytosol, and that these effects could be regulated by chaperone Hsp70-related machinery. Furthermore, aggregation of mutant huntingtin exon 1 protein (Httex1) in the cytosol appeared to outcompete and thus prevented the engagement of quality control machinery with the biosensor in the cytosol. This effect correlated with reduced levels of DNAJB1 and HSPA1A chaperones in the cell outside those sequestered to the aggregates, particularly in the nucleus. Unexpectedly, we found Httex1 aggregation also increased the apparent engagement of the barnase biosensor with quality control machinery in the nucleus suggesting an independent implementation of “holdase” activity of chaperones other than DNAJB1 and HSPA1A. Collectively, these results suggest that proteostasis stress can trigger a rebalancing of chaperone abundance in different subcellular compartments through a dynamic network involving different chaperone–client interactions.  相似文献   

19.
Oleuropein (OE) is a secoiridoid glycoside, which occurs mostly in the Oleaceae family presenting several pharmacological properties, including antioxidant, cardio-protective, anti-atherogenic effects etc. Based on these findings OE is commercially available, as Herbal Medicinal Product (HMP), claimed for its antioxidant effects. As there are general provisions of the medicine regulating bodies e.g. European Medicines Agency, the quality of the HMP’s must always be demonstrated. Therefore, a novel LC-MS methodology was developed and validated for the simultaneous quantification of OE and its main degradation product, hydroxytyrosol (HT), for the relevant OE claimed HMP’s. The internal standard (IS) methodology was employed and separation of OE, HT and IS was achieved on a C18 Fused Core column with 3.1 min overall run time employing the SIM method for the analytical signal acquisition. The method was validated according to the International Conference on Harmonisation requirements and the results show adequate linearity (r2 > 0.99) over a wide concentration range [0.1–15 μg/mL (n=12)] and a LLOQ value of 0.1 μg/mL, for both OE and HT. Furthermore, as it would be beneficial to control the quality taking into account all the substances of the OE claimed HMP’s; a metabolomics-like approach has been developed and applied for the total quality control of the different preparations employing UHPLC-HRMS-multivariate analysis (MVA). Four OE-claimed commercial HMP’s have been randomly selected and MVA similarity-based measurements were performed. The results showed that the examined samples could also be differentiated as evidenced according to their scores plot. Batch to batch reproducibility between the samples of the same brand has also been determined and found to be acceptable. Overall, the developed combined methodology has been found to be an efficient tool for the monitoring of the HMP’s total quality. Only one OE HMP has been found to be consistent to its label claim.  相似文献   

20.
The principal event underlying the development of prion disease is the conversion of soluble cellular prion protein (PrPC) into its disease-causing isoform, PrPSc. This conversion is associated with a marked change in secondary structure from predominantly α-helical to a high β-sheet content, ultimately leading to the formation of aggregates consisting of ordered fibrillar assemblies referred to as amyloid. In vitro, recombinant prion proteins and short prion peptides from various species have been shown to form amyloid under various conditions and it has been proposed that, theoretically, any protein and peptide could form amyloid under appropriate conditions. To identify the peptide segment involved in the amyloid core formed from recombinant full-length mouse prion protein mPrP(23–230), we carried out seed-induced amyloid formation from recombinant prion protein in the presence of seeds generated from the short prion peptides mPrP(107–143), mPrP(107–126), and mPrP(127–143). Our results showed that the amyloid fibrils formed from mPrP(107–143) and mPrP(127–143), but not those formed from mPrP(107–126), were able to seed the amyloidogenesis of mPrP(23–230), showing that the segment residing in sequence 127–143 was used to form the amyloid core in the fibrillization of mPrP(23–230).  相似文献   

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