Introduction: Primary air liquid interface (ALI) cultures of bronchial epithelial cells are used extensively to model airway responses. A recent advance is the development of conditional reprogramming that enhances proliferative capability. Several different media and protocols are utilized, yet even subtle differences may influence cellular responses. We compared the morphology and functional responses, including innate immune responses to rhinovirus infection in conditionally reprogrammed primary bronchial epithelial cells (pBECs) differentiated using two commonly used culture media. Methods: pBECs from healthy participants (n = 5) were CR using gamma-irradiated 3T3 fibroblasts and Rho Kinase inhibitor. CRpBECs were differentiated at ALI in either PneumaCultTM (PN-ALI) or Bronchial Epithelial Growth Medium (BEGM)-based differentiation media (BEBM:DMEM, 50:50, LonzaTM) - (AB-ALI) for 28 days. Transepithelial electrical resistance (TEER), immunofluorescence, histology, cilia activity, ion channel function, and expression of cell markers were analyzed. Viral load was assessed by RT-qPCR and anti-viral factors quantified by Legendplex following Rhinovirus-A1b (RVA1b) infection. Results: CRpBECs differentiated in PneumaCultTM were smaller and had a lower TEER and cilia beat frequency (CBF) compared to BEGM media. PneumaCultTM media cultures exhibited significantly increased FOXJ1 expression, more ciliated cells with a larger active area, increased intracellular mucins, and increased calcium-activated chloride channel current. However, there were no significant changes in viral RNA or host antiviral responses. Conclusion: There are distinct structural and functional differences in CRpBECs cultured in the two commonly used ALI differentiation media. Such factors need to be taken into consideration when designing and comparing CRpBECs ALI experiments. | Make paid
Microbes can have profound effects on host fitness and health and the appearance of late-onset diseases. Host-microbe interactions thus represent a major environmental context for healthy aging of the host and might also mediate trade-offs between life-history traits in the evolution of host senescence. Here, we have used the nematode Caenorhabditis elegans to study how host-microbe interactions may modulate the evolution of life histories and aging. We first characterized the effects of two non-pathogenic and one pathogenic Escherichia coli strains, together with the pathogenic Serratia marcescens DB11 strain, on population growth rates and survival of C. elegans from five different genetic backgrounds. We then focused on an outbred C. elegans population, to understand if microbe-specific effects on the reproductive schedule and in traits such as developmental rate and survival were also expressed in the presence of males and standing genetic variation, which could be relevant for the evolution of C. elegans and other nematode species in nature. Our results show that host-microbe interactions have a substantial host-genotype-dependent impact on the reproductive aging and survival of the nematode host. Although both pathogenic bacteria reduced host survival in comparison with benign strains, they differed in how they affected other host traits. Host fertility and population growth rate were affected by S. marcescens DB11 only during early adulthood, whereas this occurred at later ages with the pathogenic E. coli IAI1. In both cases, these effects were largely dependent on the host genotypes. Given such microbe-specific genotypic differences in host life history, we predict that the evolution of reproductive schedules and senescence might be critically contingent on host-microbe interactions in nature. | Make paid
Telomeres are prone to formation of the common oxidative lesion 8-oxoguanine (8oxoG), and the acute production of 8oxoG damage at telomeres is sufficient to drive rapid cellular senescence. OGG1 and MUTYH glycosylases initiate base excision repair (BER) at 8oxoG sites to remove the lesion or prevent mutation. Here, we show OGG1 loss or inhibition, or MUTYH loss, partially rescues telomeric 8oxoG-induced senescence, and loss of both glycosylases results in a near complete rescue. Loss of these glycosylases also suppresses 8oxoG-induced telomere fragility and dysfunction, indicating that single-stranded break (SSB) intermediates arising downstream of glycosylase activity impair telomere replication. The failure to initiate BER in glycosylase-deficient cells suppresses PARylation at SSB intermediates and confers resistance to the synergistic effects of PARP inhibitors on damage-induced senescence. Our studies reveal that inefficient completion of 8oxoG BER at telomeres triggers cellular senescence via SSB intermediates which impair telomere replication and stability. | Make paid
Soybean is the most cultivated oilseed crop in the world, with much of the merit obtained in recent years due to genetic improvement in which greater genetic progress can be obtained by improving physiological characteristics, which result in a greater impact on yield. Color spectra can be good indicators of the physiological quality of plants by quantifying the intensity of colors in the RGB spectra, being a non-destructive method that allows optimizing the collection and the number of data. We aimed to identify differences in spectral reflection between conventional, transgenic RR1 and RR2 soybean cultivars under the effect of glyphosate herbicide. The plants were cultivated in five-liter pots in a greenhouse in a randomized block design, following cultural treatments recommended for the soybean crop. Leaves of plants in vegetative stages V1 or V2 were collected and duly identified to compose a second experiment, being then submitted to incubation in plastic trays in which the treatments were organized in a completely randomized design in a 6x6 factorial scheme, with three replications. Glyphosate herbicide doses (0.0, 0.03%, 0.06%, 0.12% and 0.24% AE/ha) were added to the leaf petiole on a cotton pad in order to maintain constant contact with the respective dose. The trays were kept under ambient conditions for 14 days after incubation under 16h-light and 8h-dark of artificial light. Images were collected with a smartphone camera on the 13th day after leaves collection (DAC) in an appropriate studio to maintain adequate lighting, and on the 14th DAC SPAD index data were collected in three locations on the leaf, avoiding the midrib. The images were cropped and then segmented using manual thresholding in which the average values for the red, green and blue channels were extracted. The Excess Red Index (ExR) was calculated using the red and green channels data. The data obtained were analyzed and the significant effects of the model were analyzed by the Skott-Knott test for the cultivar factor and regression models were adjusted for the dose factor. Spearman's correlation was used to verify the relationship between the studied variables. In view of our results, glyphosate affects the chlorophyll of resistant plants when subjected to continuous exposure and at high doses, leading to senescence and that the red channel information can be used to infer the level of interference in the photosynthetic activity of plants subjected to the herbicide. | Make paid
ObjectiveMeasures that capture aging-related decline can identify patients at risk for cardiac surgery-associated adverse events to guide perioperative care and improve patient outcomes. We determined if a panel of biomarkers of cellular senescence, a fundamental aging mechanism, can predict risk of adverse kidney and cardiac events in patients undergoing CABG surgery. MethodsPatients to undergo CABG with or without valve repair or replacement were recruited into a pilot cohort of 66 patients and a development cohort of 331 patients. Blood samples were collected prior to surgery for assessment of expression of preselected biomarkers of senescence. Patients were followed through hospital stay and up to a 30d post-surgery. Daily post-op serum creatinine (sCR) was used to identify incidence of acute kidney injury (AKI) and sCr measures at 30 days were used to identify patients whose eGFR decreased 25% or more as compared to baseline (development cohort only). A composite of major adverse cardiac and kidney events (MACKE30) was used as another endpoint in development cohort only. ResultsAKI occurred in 30.0% of patients in pilot study and 19.9% of development cohort. Persistent decline in kidney function at 30d occurred in 11.0%, and MACKE30 in 13.4% of patients. A panel of six biomarkers of senescence (p16, p14, LAG3, CD244, Cd28 and suPAR) were able to identify patients at risk for AKI (AUC 0.76), kidney decline at 30d (AUC 0.73), and MACKE30 (AUC 0.71). When compared between top and bottom tertiles of senescence-based risk models, patients in the top tertile had 7.8 (3.3-8.4) higher odds of developing AKI, 4.5 (1.6-12.6) higher odds of developing renal decline at 30d, and 5.7 (2.1-15.6) higher odds of developing MACKE30. All models remained significant when adjusted for clinical variables Surprisingly, patients with kidney function decline and AKI were largely non-overlapping, and potentially of different etiology. Typical clinical factors that predispose to AKI (e.g., age, CKD, surgery type) associated with AKI but not the 30d decline endpoint. Instead, a new-onset atrial fibrillation associated with 30d kidney decline and not AKI. ConclusionsA 6-member panel of biomarkers of senescence, a fundamental mechanism of aging, can identify patients for risk of adverse kidney and cardiac events when measured pre-operatively. | Make paid
Background Depression is a common and disabling condition. Digital apps may augment or facilitate care, particularly in under-served populations. We tested the efficacy of juli, a digital self-management app for depression in a fully remote randomized controlled trial. Methods We completed a pragmatic single-blind trial of juli for depression. We included participants aged over 18 who self-identified as having depression and scored 5 or more on the Patient Health Questionnaire-8 (PHQ-8). Participants were randomly assigned (1:1) to receive juli for 8 weeks or a limited attention-placebo control version of the app. Our primary outcome was the difference in PHQ-8 scores at 8 weeks. Secondary outcomes were remission, minimal clinically important difference, worsening of depression, and health-related quality of life. Analyses were per protocol (primary) and modified intention-to-treat (secondary). The trial was registered at the ISRCTN registry (ISRCTN12329547). Results Between May 2021 and January 2023, we randomised 908 participants. 662 completed the week 2 outcome assessment and were included in the modified intention-to-treat analysis, and 456 completed the week 8 outcome assessments (per protocol). The mean baseline PHQ-8 score was consistent with a diagnosis of moderately severe depression. In the per-protocol analysis, the juli group had a lower mean PHQ-8 score (10.78, standard deviation 6.26) than the control group (11.88, standard deviation 5.73) by week 8 (baseline adjusted beta-coefficient -0.94, 95%CI -1.87 to -0.22, p=0.045). Remission and minimal clinically important difference were increased in the juli group at 8 weeks (adjusted odds ratio 2.22, 95%CI 1.45-3.39, p<0.001 and adjusted odds ratio 1.56, 95%CI 1.08 to 2.27, p=0.018). There were no between-group differences in health-related quality of life physical or mental component scores or worsening of depression. Conclusion Use of juli reduced symptoms of depression at 8 weeks compared with an attention-placebo control. The juli app is a digital self-management tool that could increase accessibility of evidence-based depression treatments. | Make paid
Background: Physical activity is strongly protective against the development of chronic diseases associated with aging. We previously demonstrated that digital interventions delivered through a smartphone app can increase short-term physical activity. Our randomized crossover trial has continued to digitally enroll participants, allowing increasing statistical power for greater precision in subsequent analyses. Methods: We offered enrollment to adults aged >=18 years with access to an iPhone and the MyHeart Counts app. After completion of a 1-week baseline period, e-consented participants were randomly allocated to four 7-day interventions. Interventions consisted of: 1) daily personalized e-coaching based on the individuals baseline activity patterns, 2) daily prompts to complete 10,000 steps, 3) hourly prompts to stand following inactivity, and 4) daily instructions to read guidelines from the American Heart Association website. The trial was completed in a free-living setting, where neither the participants or investigators were blinded to the intervention. The primary outcome was change in mean daily step count from baseline for each of the four interventions, assessed in a modified intention-to-treat analysis. This trial is registered with ClinicalTrials.gov, NCT03090321. Findings: Between January 1, 2017 and April 1, 2022, 4500 participants consented to enroll in the trial, of whom 2458 completed 7-days of baseline monitoring (mean daily steps 4232+/-73) and at least one day of one of the four interventions. The greater statistical power afforded by continued passive enrollment revealed that e-coaching prompts, tailored to an individual, increased step count significantly more than other interventions (402+/-71 steps, P=7.1x10-8). Interpretation: Digital studies can continuously recruit participants in a cost-effective manner, allowing for new insights provided by increased statistical power and refinement of prior signals. Here, we show that digital interventions tailored to an individual are effective in increasing short-term physical activity in a free-living cohort. Funding: Stanford Data Science Initiative and Catalyst Program, Apple, Google | Make paid
Clearance of senescent cells has demonstrated therapeutic potential in the context of chronic age-related diseases. Little is known, however, how clearing senescent cells affects the ability to respond to an acute infection and form quality immunological memory. We aimed to probe the effects of clearing senescent cells in aged mice on the immune response to influenza (flu) infection. We utilized a p16 trimodality reporter mouse model (p16-3MR) to allow for identification and selective deletion of p16-expressing senescent cells upon administration of ganciclovir (GCV). While p16-expressing senescent cells may exacerbate dysfunctional responses to a primary infection, our data suggest they may play a role in fostering memory cell generation. We demonstrate that although deletion of p16-expressing cells enhanced viral clearance, this also severely limited antibody production in the lungs of flu-infected aged mice. 30 days later, there were fewer flu-specific CD8 memory T cells and lower levels of flu-specific antibodies in the lungs of GCV treated mice. GCV treated mice were unable to mount an optimal memory response and demonstrated increased viral load following a heterosubtypic challenge. These results suggest that targeting senescent cells may potentiate primary responses while limiting the ability to form durable and protective immune memory with age. | Make paid
Background: Delirium is an acute mental disorder and a common postoperative complication. Age is an independent marker of the development of postoperative delirium. In older patients, delirium leads to numerous detrimental effects. We will mainly explore the incidence and potential risk variables of postoperative delirium in older patients undergoing spinal surgery, focusing on some preoperative and intraoperative indicators. Study design and methods: This single-center prospective, observational, cohort study will investigate the incidence of delirium in patients aged [≥]65 years undergoing spinal surgery and construct a postoperative delirium risk prediction model. We will use potential multiple risk factors reported in recent studies. Follow-up starts on the first day after the operation, and delirium assessment is conducted until 7 days after the operation. The least absolute shrinkage and selection operator regression will be used to filter variables, and logistic regression will be utilized to build a prediction model using the selected variables. The area under the receiver operating characteristic curve will be used to evaluate the accuracy of the prediction model. The clinical net benefit of the model will be evaluated using decision curve analysis. Discussion: This study will construct a clinically effective model to predict the occurrence of postoperative delirium in older patients undergoing spinal surgery. Keywords: spinal surgery, delirium, risk prediction model, older patients | Make paid
COVID-19 affects the population unequally with a higher impact on aged and immunosuppressed people. Hence, we assessed the effect of SARS-CoV-2 vaccination in immune compromised patients (older adults and oncohematologic patients), compared with healthy counterparts. While the acquired humoral and cellular memory did not predict subsequent infection 18 months after full immunization, spectral and computational cytometry revealed several subsets within the CD8+ T-cells, B-cells, NK cells, monocytes and CD45RA+CCR7- T{gamma}{delta} cells differentially expressed in further infected and non-infected individuals not just following immunization, but also prior to that. Of note up to 7 subsets were found within the CD45RA+CCR7- T{gamma}{delta} population with some of them being expanded and other decreased in subsequently infected individuals. Moreover, some of these subsets also predicted COVID-induced hospitalization in oncohematologic patients. Therefore, we hereby have identified several cellular subsets that, even before vaccination, strongly related to COVID-19 vulnerability as opposed to the acquisition of cellular and/or humoral memory following vaccination with SARS-CoV-2 mRNA vaccines. | Make paid
Neuronal cell death and subsequent brain dysfunction are hallmarks of aging and neurodegeneration, but how the nearby healthy neurons (bystanders) respond to the cell death of their neighbors is not fully understood. In the Drosophila larval neuromuscular system, bystander motor neurons can structurally and functionally compensate for the loss of their neighbors by increasing their axon terminal size and activity. We termed this compensation as cross-neuron plasticity, and in this study, we demonstrated that the Drosophila engulfment receptor, Draper, and the associated kinase, Shark, are required in glial cells. Surprisingly, overexpression of the Draper-I isoform boosts cross-neuron plasticity, implying that the strength of plasticity correlates with Draper signaling. Synaptic plasticity normally declines as animals age, but in our system, functional cross-neuron plasticity can be induced at different time points, whereas structural cross-neuron plasticity can only be induced at early stages. Our work uncovers a novel role for glial Draper signaling in cross-neuron plasticity that may enhance nervous system function during neurodegeneration and provides insights into how healthy bystander neurons respond to the loss of their neighboring neurons. | Make paid
Clathrin plays a critical role in clathrin-mediated endocytosis (CME) in plants, and it is required for autophagy in mammals. However, the functional interconnection of clathrin with autophagy has not been firmly established in plants. We demonstrate that loss of function of clathrin light chain (CLC) subunit 2 and 3 results in salicylic acid (SA)- and H2O2-dependent accelerated senescence and activated defense responses in Arabidopsis, which are hallmarks displayed in autophagy-related gene (ATG) mutants. Similar to atg mutants, the clc2-1clc3-1 double mutant has enhanced sensitivity to both carbon and nitrogen starvation and enhanced resistance to biotrophic bacterial and fungal pathogens. In addition, the autophagy flux was significantly reduced in the roots of clc2-1clc3-1 mutant plants relative to Col-0 plants under carbon starvation conditions. Furthermore, our Yeast-2-hybrid (Y2H) and Luciferase complementation assays showed that CLC2 directly interacted with ATG8h and ATG8i. Mutations within the unique ATG8-interacting motif (AIM) of CLC2 as well as at the LIR/AIM-docking site of ATG8h abolished the interaction between CLC2 and ATG8h. As anticipated, both GFP-ATG8h/GFP-ATG8i and CLC2 were subjected to autophagic degradation in the vacuoles. Together, our data revealed that the accelerated senescence and activated immune responses observed in Arabidopsis clc2-1clc3-1 mutant plants result from impaired autophagy, and CLC2 participates in autophagy through directly interactions with ATG8h and ATG8i in an AIM- and LDS-dependent manner. Our results unveil a previously unidentified link between the function of CLCs and autophagy. | Make paid
Cancer cells frequently undergo metabolic reprogramming as a mechanism of resistance against chemotherapeutic drugs. Metabolomic profiling provides a direct readout of metabolic changes and can thus be used to identify these tumor escape mechanisms. Here, we introduce piTracer, a computational tool that uses multi-scale molecular networks to identify potential combination therapies from pre- and post-treatment metabolomics data. We first demonstrate piTracer's core ability to reconstruct cellular cascades by inspecting well-characterized molecular pathways and previously studied associations between genetic variants and metabolite levels. We then apply a new gene ranking algorithm on differential metabolomic profiles from human breast cancer cells after glutaminase inhibition. Four of the automatically identified gene targets were experimentally tested by simultaneous inhibition of the respective targets and glutaminase. Of these combination treatments, two were be confirmed to induce synthetic lethality in the cell line. In summary, piTracer integrates the molecular monitoring of escape mechanisms into comprehensive pathway networks to accelerate drug target identification. The tool is open source and can be accessed at https://github.com/krumsieklab/pitracer. | Make paid
Protein homeostasis (a.k.a. proteostasis) is associated with the primary functions of life, and therefore with evolution. However, it is unclear how the cellular proteostasis machines have evolved to adjust the protein biogenesis needs to environmental constraints. Herein, we describe a novel computational approach, based on semantic network analysis, to evaluate proteostasis differentiation during evolution. We show that the molecular components of the proteostasis network (PN) are reliable metrics to deconvolute the life forms into Archaea, Bacteria and Eukarya and to assess the evolution rates among species. Topological properties of semantic graphs were used as new criteria to evaluate PN complexity of 93 Eukarya, 250 Bacteria and 62 Archaea, thus representing a novel strategy for taxonomic classification. This functional analysis provides information about species divergence and pointed towards taxonomic clades that evolved faster than others. Kingdom-specific PN were identified, suggesting that PN complexity correlates evolution. Through the analysis of gene conservation, we found that the gains or losses that occurred throughout PN evolution revealed a dichotomy within both the PN conserved modules and within kingdom-specific modules. Since the PN is implicated in cell fitness, aging and disease onset, it could be used as a new metric to tackle mechanisms underlying gain-of-functions, and their biological ramifications. | Make paid
Our recent data showed that an aberrant IL-10-producing T follicular helper population (Tfh10) accumulates dramatically with age and is associated with age-related declines in vaccine responsiveness. Through single cell RNA sequencing and chromatin accessibility analysis of IL-10+ and IL-10- memory CD4+ T cells from young and aged mice, we identified increased expression of CD153 on aged Tfh and Tfh10 cells. Mechanistically, we linked inflammaging (increased IL-6 levels) to elevated CD153 expression of Tfh cells through c-Maf. Surprisingly, blockade of CD153 in aged mice significantly reduced their vaccine-driven antibody response, which was associated with decreased expression of ICOS on antigen-specific Tfh cells. Combined, these data show that an IL-6/c-Maf/CD153 circuit is critical for maintaining ICOS expression. Thus, although overall Tfh-mediated B cell responses are reduced in the context of vaccines and aging, our data suggest that elevated expression of CD153 on Tfh cells potentiates the remaining Tfh function in aged mice. | Make paid
Rodent gait analysis is crucial for modeling human aging, but the lack of comprehensive research on gait in elderly mice limits our ability to translate findings from animal models to human populations. Age-related changes in C57BL/10 strain remain unknown. The state of art protocol for gait analysis uses the CatWalk TM XT system that allows an understanding of the locomotion pattern by a variety of parameters. We aim to provide relevant information for experimental designs, presenting benchmark data on the performance of locomotion using healthy wild-type mice for future preclinical investigations of neurological and neuromuscular gait patterns. In this study, characterization of walking locomotion was demonstrated from complete gait analysis in aged C57BL/10ScCr/PasUnib mice using open-field, CatWalk, and treadmill tests. Mice were divided into the adult group (6 months; n = 9) and the aged group (20 months; n = 9). Aged mice demonstrated decreased mobility, distance traveled, and general speed in the open-field test. The spatiotemporal and kinetic parameters were altered in aged mice, with lower speed, higher stand time and stride length, and increased base of support and duty cycle in comparison with adult mice. Interlimb coordination has changed in elderly mice. To test whether speed alters the temporal parameters, we used a treadmill test and we demonstrated higher stand time in 20-month-old mice. We demonstrated that changes in gait parameters and mobility represent direct age-related singularities in the wild-type C57BL/10 mice. Overall, aged mice took more time in contact with the ground independently of the speed. These baseline gait results shed light on measures that allow the potential investigation of therapeutics and interventions in gerontology or neuromuscular diseases. | Make paid
Nutritional interventions in healthy individuals may be particularly informative if high, but not excessive, amounts of specific healthy foods are taken to maximize effects without sacrificing safety. We hypothesized that high amounts of polyphenols taken on single days may eliminate senescent blood cells. We conducted a ten-week parallel-group controlled randomized open trial with an escalation of consumption, up to ~4kg fresh strawberries weekly, plus 200g dried strawberries and 240g capers in olive oil on three single "seno-intervention" days, in 168 healthy elderly people aged 50-80 years. Two primary endpoints, LDL cholesterol and high sensitive CRP, were prespecified. We found a significant decline in LDL cholesterol, and in CRP by ~50% in all groups with seno-intervention days (limited to participants with increased baseline values). LDL levels were reduced by 0.0174 mmol/L for any single 500g-increment in the weekly fresh strawberry intake of the average participant. Gene expression analyses of whole blood suggested improvement of mitochondrial and immunological function, suppression of inflammation (in high-intervention groups), and positive regulation of apoptotic signaling (in the highest-intervention group). Overall, a medium-term nutritional intervention improved lipid and inflammation status, and provided specific hints for apoptotic/senolytic effects. | Make paid
Adrenocortical carcinoma (ACC) is a rare cancer of the adrenal gland with generally very unfavourable outcome. Two molecular subgroups, C1A and C1B, have been previously identified with a significant association with patient survival. In this work, we study chromatin state organization characterized by histone modifications using ChIP-sequencing in adult ACC. We describe the super-enhancer landscape of ACC, characterized by H3K27ac, and identify super-enhancer regulated genes that play a significant role in tumorigenesis. We show that the super-enhancer landscape reflects differences between the molecular sub- groups C1A and C1B and identify networks of master transcription factors mirroring these differences. Additionally, we study the effects of molecules THZ1 and JQ1 previously reported to affect super-enhancer-driven gene expression in ACC cell lines. Our results reveal that the landscape of histone modifications in ACC is linked to its molecular subgroups and thus provide the groundwork for future analysis of epigenetic reprogramming in ACC. | Make paid
Protein homeostasis (a.k.a. proteostasis) is associated with the primary functions of life, and therefore with evolution. However, it is unclear how the cellular proteostasis machines have evolved to adjust the protein biogenesis needs to environmental constraints. Herein, we describe a novel computational approach, based on semantic network analysis, to evaluate proteostasis differentiation during evolution. We show that the molecular components of the proteostasis network (PN) are reliable metrics to deconvolute the life forms into Archaea, Bacteria and Eukarya and to assess the evolution rates among species. Topological properties of semantic graphs were used as new criteria to evaluate PN complexity of 93 Eukarya, 250 Bacteria and 62 Archaea, thus representing a novel strategy for taxonomic classification. This functional analysis provides information about species divergence and pointed towards taxonomic clades that evolved faster than others. Kingdom-specific PN were identified, suggesting that PN complexity correlates evolution. Through the analysis of gene conservation, we found that the gains or losses that occurred throughout PN evolution revealed a dichotomy within both the PN conserved modules and within kingdom-specific modules. Since the PN is implicated in cell fitness, aging and disease onset, it could be used as a new metric to tackle mechanisms underlying gain-of-functions, and their biological ramifications. | Make paid
Background and Aims: Loss of hepatocyte identity is associated with impaired liver function in alcohol-related hepatitis (AH). In this context, hepatocyte dedifferentiation gives rise to cells with a hepatobiliary (HB) phenotype expressing biliary and hepatocytes markers and showing immature features. However, the mechanisms and the impact of hepatocyte dedifferentiation in liver disease are poorly understood. Methods: HB cells and ductular reaction (DR) cells were quantified and microdissected from liver biopsies from patients with alcohol-related liver disease (ALD). Hepatocyte-specific overexpression or deletion of CXCR4, and CXCR4 pharmacological inhibition were assessed in mouse liver injury. Patient-derived and mouse organoids were generated to assess plasticity. Results: Here we show that HB and DR cells are increased in patients with decompensated cirrhosis and AH, but only HB cells correlate with poor liver function and patients outcome. Transcriptomic profiling of HB cells revealed the expression of biliary-specific genes and a mild reduction of hepatocyte metabolism. Functional analysis identified pathways involved in hepatocyte reprogramming, inflammation, stemness and cancer gene programs. CXCR4 pathway was highly enriched in HB cells, and correlated with disease severity and hepatocyte dedifferentiation. In vitro, CXCR4 was associated with biliary phenotype and loss of hepatocyte features. Liver overexpression of CXCR4 in chronic liver injury decreased hepatocyte specific gene expression profile and promoted liver injury. CXCR4 deletion or its pharmacological inhibition ameliorated hepatocyte dedifferentiation and reduced DR and fibrosis progression. Conclusions: This study shows the association of hepatocyte dedifferentiation with disease progression and poor outcome in AH. Moreover, the transcriptomic profiling of HB cells revealed CXCR4 as a new driver of hepatocyte-to-biliary reprogramming and as a potential therapeutic target to halt hepatocyte dedifferentiation in AH. | Make paid
Background: Blood-brain barrier (BBB) breakdown is a component of the progression and pathology of Alzheimer's disease (AD). BBB dysfunction is primarily caused by reduced or disorganized tight junction or adherens junction proteins of brain microvascular endothelial cell (BMEC). While there is growing evidence of tight junction disruption in BMECs in AD, the functional role of adherens junctions during BBB dysfunction in AD remains unknown. Exosomes secreted from senescent cells have unique characteristics and contribute to modulating the phenotype of recipient cells. However, it remains unknown if and how these exosomes cause BMEC dysfunction in AD. Objectives: This study aimed to investigate the potential roles of AD circulating exosomes and their RNA cargos in brain endothelial dysfunction in AD. Methods: We isolated exosomes from sera of five cases of AD compared with age- and sex-matched cognitively normal controls using size-exclusion chromatography technology. We validated the qualities and particle sizes of isolated exosomes with nanoparticle tracking analysis and atomic force microscopy. We measured the biomechanical natures of the endothelial barrier of BMECs, the lateral binding forces between live BMECs, using fluidic force miscopy. We visualized the paracellular expressions of the key adherens junction protein VE-cadherin in BMEC cultures and a 3D BBB model that employs primary human BMECs and pericytes with immunostaining and evaluated them using confocal microscopy. We also examined the VE-cadherin signal in brain tissues from five cases of AD and five age- and sex-matched cognitively normal controls. Results: We found that circulating exosomes from AD patients suppress the paracellular expression levels of VE-cadherin and impair the barrier function of recipient BMECs. Immunostaining analysis showed that AD circulating exosomes damage VE-cadherin integrity in a 3D model of microvascular tubule formation. We found that circulating exosomes in AD weaken the BBB depending on the RNA cargos. In parallel, we observed that microvascular VE-cadherin expression is diminished in AD brains compared to normal controls. Conclusion: Using in vitro and ex vivo models, our study illustrates that circulating exosomes from AD patients play a significant role in mediating the damage effect on adhesions junction of recipient BMEC of the BBB in an exosomal RNA-dependent manner. This suggests a novel mechanism of peripheral senescent exosomes for AD risk. | Make paid
Seed increase through manual pollination is a critical part of maize breeding and genetics research to advance generations in breeding programs, to create desired research crosses, and produce hybrid seed for trials. Pollination in the field and in controlled environments relies on the availability of high-quality pollen at the time that recipient silks are receptive. Generally, pollinations are made by capturing pollen from the tassel in a paper pollinating bag placed on the tassels one day prior to pollination and newly released pollen is then transferred to silks on the target plant. In the field, maize pollen is only viable for one to four hours following dehiscence and the rate of desiccation is influenced by environmental conditions. We have developed a method which increases the lifespan of pollen and allows pollen from a single tassel to be used to pollinate many ears by mixing fresh pollen with a dilutant that can be stored for multiple days. We identified characteristics of the size of suitable substrates and selected a PEEK based substrate for regular utilization. We evaluated pollen viability and empirically demonstrated the capability to store pollen up to nine days when pollen is mixed with a PEEK substrate and stored at 6 degrees Celsius. The pollen storage method was used to make successful pollinations across 24 maize inbred lines tested and was generally equivalent to the standard manual pollination process. This method has the potential to increase the efficiency of breeding operations and may be useful in an array of genetic studies. | Make paid
Touch generated by our voluntary movements is attenuated both at the perceptual and neural level compared to touch of the same intensity delivered to our body by another person or machine. This somatosensory attenuation phenomenon is considered to rely on the integration of somatosensory input and predictions about the somatosensory consequences of our actions. Previous studies have reported increased somatosensory attenuation in elderly people, proposing an overreliance on sensorimotor predictions to compensate for age-related declines in somatosensory perception; however, recent results have challenged this relationship. In a preregistered study, we used a force-discrimination task to assess whether aging increases somatosensory attenuation and whether this increase is explained by decreased somatosensory precision in elderly individuals. Although we observed significant somatosensory attenuation in 94% of our sample (n = 108, 21-77 years old) regardless of age, we did not find a significant increase in somatosensory attenuation in our elderly participants (65-77 years old) unless we included only the oldest subset (69-77 years old). Moreover, we did not observe a significant age-related decline in somatosensory precision or a significant relationship of age with somatosensory attenuation. Together, our results suggest that aging exerts a limited influence on the perception of self-generated and externally generated touch and prompt reconsideration of the proposed direct relationship between somatosensory precision and attenuation in elderly individuals. | Make paid
Nutritional interventions in healthy individuals may be particularly informative if high, but not excessive, amounts of specific healthy foods are taken to maximize effects without sacrificing safety. We hypothesized that high amounts of polyphenols taken on single days may eliminate senescent blood cells. We conducted a ten-week parallel-group controlled randomized open trial with an escalation of consumption, up to ~4kg fresh strawberries weekly, plus 200g dried strawberries and 240g capers in olive oil on three single "seno-intervention" days, in 168 healthy elderly people aged 50-80 years. Two primary endpoints, LDL cholesterol and high sensitive CRP, were prespecified. We found a significant decline in LDL cholesterol, and in CRP by ~50% in all groups with seno-intervention days (limited to participants with increased baseline values). LDL levels were reduced by 0.0174 mmol/L for any single 500g-increment in the weekly fresh strawberry intake of the average participant. Gene expression analyses of whole blood suggested improvement of mitochondrial and immunological function, suppression of inflammation (in high-intervention groups), and positive regulation of apoptotic signaling (in the highest-intervention group). Overall, a medium-term nutritional intervention improved lipid and inflammation status, and provided specific hints for apoptotic/senolytic effects. | Make paid
Strategies to improve the immunogenicity of COVID-19 vaccines are necessary to optimise their protection against disease. Fractional dosing by intradermal administration (ID) has been shown to be equally immunogenic as intramuscular (IM) for several vaccines, but the immunogenicity of ID inactivated whole-virus SARS-CoV-2 at the full dose is unknown. This study (NCT04800133) investigated the superiority of antibody and T cell responses of full-dose CoronaVac by ID over IM in adolescents. Participants aged 11-17 years received 2 doses IM or ID, followed by the 3rd dose 13-42 days later. Humoral and cellular immunogenicity outcomes were measured post-dose 2 (IM-CC versus ID-CC) and post-dose 3 (IM-CCC versus ID-CCC). Doses 2 and 3 were administered to 173 and 104 adolescents, respectively. S IgG, S-RBD IgG, S IgG Fc{gamma}RIIIa-binding, SNM-specific IL-2+CD4+, SNM-specific IL-2+CD8+, S-specific IL-2+CD8+, N-specific IL-2+CD4+, N-specific IL-2+CD8+ and M-specific IL-2+CD4+ responses fulfilled the superior and non-inferior criteria for ID-CC compared to IM-CC, whereas IgG avidity was inferior. For ID-CCC, S-RBD IgG, surrogate virus neutralisation test (sVNT), 90% plaque reduction neutralisation titre (PRNT90), PRNT50, S IgG avidity, S IgG Fc{gamma}RIIIa-binding, M-specific IL-2+CD4+, interferon-{gamma}+CD8+ and IL-2+CD8+ responses were superior and non-inferior to IM-CCC. The estimated vaccine efficacies were 49%, 52%, 66% and 79% for IM-CC, ID-CC, IM-CCC and ID-CCC, respectively. More in the ID groups reported local, mild adverse reactions. This is the first study to demonstrate superior antibody and M-specific T cell responses by ID inactivated SARS-CoV-2 vaccination and serves as the basis for future research to improve immunogenicity of inactivated vaccines. | Make paid
Bacterial volatile compounds have emerged as important chemical messengers between bacteria themselves as well as in their interactions with other organisms. One of the earliest examples of bioactive volatiles emitted by bacteria is hydrogen cyanide (HCN), which was long considered a mere respiratory toxin conferring competitive advantage to cyanogenic strains. Using cyanide-deficient mutants in two Pseudomonas strains and global transcriptome analysis, we demonstrate that the impact of HCN is much more global than previously thought. We first observed that the lack of cyanogenesis in emitting strains led to massive transcriptome reprogramming affecting diverse traits such as motility and biofilm formation (respectively inhibited vs. promoted by HCN), or the production of siderophores, phenazines and other antimicrobial compounds (repressed by HCN). We then exposed non-cyanogenic strains to biogenically emitted HCN from neighboring cells and observed similar transcriptome modulations and phenotypic changes, suggesting that HCN not only acts endogenously but also exogenously, remotely manipulating important traits involved in competition and virulence, e.g. siderophore production, in other organisms. Cyanogenesis in Pseudomonas has long been known to play a role in both the virulence of opportunistic pathogens and the efficient biocontrol activity of plant-beneficial strains, however this impact was so far thought to occur solely through the inhibition of respiration. We demonstrate here new ecological roles for a small and fast-diffusing volatile compound, which opens novel avenues in our understanding of and ability to interfere with important processes taking place in pathogenic and beneficial Pseudomonas strains. | Make paid
Exercise training prevents age-related decline in muscle function. Targeting epigenetic aging is a promising actionable mechanism and late-life exercise mitigates epigenetic aging in rodent muscle. Whether exercise training can decelerate, or reverse epigenetic aging in humans is unknown. Here, we performed a powerful meta-analysis of the methylome and transcriptome of an unprecedented number of human skeletal muscle samples (n = 3,176). We show that: 1) individuals with higher baseline aerobic fitness have younger epigenetic and transcriptomic profiles, 2) exercise training leads to significant shifts of epigenetic and transcriptomic patterns towards a younger profile, and 3) muscle disuse 'ages' the transcriptome. Higher fitness levels were associated with attenuated differential methylation and transcription during aging. Furthermore, both epigenetic and transcriptomic profiles shifted towards a younger state after exercise training interventions, while the transcriptome shifted towards an older state after forced muscle disuse. We demonstrate that exercise training targets many of the age-related transcripts and DNA methylation loci to maintain younger methylome and transcriptome profiles, specifically in genes related to muscle structure, metabolism and mitochondrial function. Our comprehensive analysis will inform future studies aiming to identify the best combination of therapeutics and exercise regimes to optimize longevity. | Make paid
The glymphatic system that clears out brain wastes, such as amyloid-{beta} (A{beta}) and tau, through cerebrospinal fluid (CSF) flow may play an important role in aging and dementias. However, a lack of non-invasive tools to assess the glymphatic function in humans hindered the understanding of the glymphatic changes in healthy aging. The global infra-slow (<0.1 Hz) brain activity measured by the global mean resting-state fMRI signal (gBOLD) was recently found to be coupled by large CSF movements. This coupling has been used to measure the glymphatic process and found to correlate with various pathologies of Alzheimers disease (AD), including A{beta} pathology. Using resting-state fMRI data from a large group of 719 healthy aging participants, we examined the sex-specific changes of the gBOLD-CSF coupling, as a measure of glymphatic function, over a wide age range between 36-100 years old. We found that this coupling index remains stable before around age 55 and then starts to decline afterward, particularly in females. Menopause may contribute to the accelerated decline in females. | Make paid
Plant infection by microbial pathogens is a dynamic process. Here, we investigated the heterogeneity of plant responses in the context of pathogen location. A single-cell atlas of Arabidopsis thaliana leaves challenged by the fungus Colletotrichum higginsianum revealed cell type-specific gene expression that highlights an enrichment of intracellular immune receptors in vasculature cells. Using trajectory inference, we assigned cells that directly interacted with the invasive hyphae. Further analysis of cells at these infection sites revealed transcriptional plasticity based on cell type. A reprogramming of abscisic acid signalling was specifically activated in guard cells. Consistently, a contact-dependent stomatal closure was observed, possibly representing a defense response that anticipates pathogen invasive growth. We defined cell type-specific deployments of genes activating indole glucosinolate biosynthesis at the infection sites, and determined their contribution to resistance. This research highlights the spatial dynamics of plant response during infection and reveals cell type-specific processes and gene functions. | Make paid
Introduction As health reforms move Ireland from a mixed public-private system toward universal healthcare, it is important to understand variations in prescribing practice for patients with differing health cover and socioeconomic status. This study aims to determine how prescribing patterns for patients aged [≥]65 years in primary care in Ireland differ between patients with public and private health cover. Methods This was an observational study using anonymised data collected as part of a larger study from 44 general practices in Ireland (2011-2018). Data were extracted from electronic records relating to demographics and prescribing for patients aged [≥]65 years. The cohort was divided between those with public health cover (via the General Medical Services (GMS) scheme) and those without. Standardised rates of prescribing were calculated for pre-specified drug classes. We also analysed the number of medications, polypharmacy, and trends over time between groups, using multilevel linear regression adjusting for age and sex. Results Overall, 42,456 individuals were included (56% female). Most were covered by the GMS scheme (62%, n=26,490). The rate of prescribing in all medication classes was higher for GMS patients compared to non-GMS patients, with the greatest difference in benzodiazepine anxiolytics. The mean number of unique medications prescribed to GMS patients was 10.9 (SD 5.9), and 8.1 (SD 5.8) for non-GMS patients. The number of unique medications prescribed to both GMS and non-GMS cohorts increased over time. The increase was steeper in the GMS group where the mean number of medications prescribed increased by 0.67 medications/year. The rate of increase was 0.13 (95%CI 0.13, 0.14) medications/year lower for non-GMS patients, a statistically significant difference. Conclusion Our study found a significantly larger number of medicines were prescribed to patients with public health cover, compared to those without. Increasing medication burden and polypharmacy among older adults may be accelerated for those of lower socioeconomic status. These findings may inform planning for moves towards universal health care, and this would provide an opportunity to evaluate the effect of expanding entitlement on prescribing and medicines use. | Make paid