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As the molecular mechanisms of biological aging become better understood, there is growing interest in identifying interventions that target those mechanisms to promote extended health and longevity. The budding yeast Saccharomyces cerevisiae has served as a premier model organism for identifying genetic and molecular factors that modulate cellular aging and is a powerful system in which to evaluate candidate longevity interventions. Here we screened a collection of natural products and natural product mixtures for effects on the growth rate, mTOR-mediated growth inhibition, and replicative lifespan. No mTOR inhibitory activity was detected, but several of the treatments affected growth rate and lifespan. The strongest lifespan shortening effects were observed for green tea extract and berberine. The most robust lifespan extension was detected from an extract of Pterocarpus marsupium and another mixture containing Pterocarpus marsupium extract. These findings illustrate the utility of the yeast system for longevity intervention discovery and identify Pterocarpus marsupium extract as a potentially fruitful longevity intervention for testing in higher eukaryotes. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11357-021-00418-x.

The University of Washington Nathan Shock Center of Excellence in the Biology of Aging in conjunction with the Healthy Aging and Longevity Research Institute held its annual geroscience symposium virtually on October 23, 2020. The symposium was divided into three sessions: (I) organ aging and growth signaling, (II) neurodegeneration and metabolism, and (III) innovative approaches in geroscience and aging research. Nine speakers affiliated with the University of Washington and three invited guest speakers, predominantly trainee, and junior faculty presented their research. Here, we summarize research presented during the symposium. A geroscience special issue, of which this is a part, collects submissions from symposium presenters as well as trainees supported by the Biological Mechanisms of Healthy Aging training program.

Caution around the fountain of youth The scientific and popular literature is full of claims for diets that delay or reverse the aging process (at least in model organisms). But how do these interventions work? Is it the amount of food, the timing of food intake, the proportion of certain macronutrients? In a Review, Lee et al . explore the fact and fiction of dietary prescriptions for a healthier and longer life. They propose that one unifying concept may be convergence on the signaling pathway mediated by the protein kinase mTOR (mechanistic target of rapamycin). Another conclusion is that the efficacy and safety of these diets for humans largely remain to be established. —LBR

To understand the genetic basis and selective forces acting on longevity, it is useful to examine lifespan variation among closely related species, or ecologically diverse isolates of the same species, within a controlled environment. In particular, this approach may lead to understanding mechanisms underlying natural variation in lifespan. Here, we analyzed 76 ecologically diverse wild yeast isolates and discovered a wide diversity of replicative lifespan (RLS). Phylogenetic analyses pointed to genes and environmental factors that strongly interact to modulate the observed aging patterns. We then identified genetic networks causally associated with natural variation in RLS across wild yeast isolates, as well as genes, metabolites, and pathways, many of which have never been associated with yeast lifespan in laboratory settings. In addition, a combined analysis of lifespan-associated metabolic and transcriptomic changes revealed unique adaptations to interconnected amino acid biosynthesis, glutamate metabolism, and mitochondrial function in long-lived strains. Overall, our multiomic and lifespan analyses across diverse isolates of the same species shows how gene–environment interactions shape cellular processes involved in phenotypic variation such as lifespan.

Blackfoot language is an endangered language that needs to be documented, analyzed, and preserved. Blackfoot is challenging to learn and teach because it is a pitch accent language whose words with same characters can take on different meanings when changing in pitch. Linguistics researchers are working to create visual aids, called Pitch Art, to teach the nuance in pitch changes. However, the existing techniques used to create Pitch Art fail to accurately indicate changes in pitch and require time-consuming work across multiple applications. To address this issue, this project proposes a system called MeTILDA (Melodic Transcription in Language Documentation and Application) to provide new forms of audio analysis and to automate the process of creating Pitch Art. MeTILDA provides value to a variety of stakeholders. Linguistics researchers are provided with tools to analyze and compare Blackfoot speeches. Teachers are given collections of words and recordings from native speakers to teach students. Students are given the ability to compare their own pronunciation of Blackfoot words to that of native speakers. We also present a new form of audio analysis, called perceptual scale, to provide more effective visuals of perceived changes in pitch movement. By collaborating with domain experts in this field, we have validated the effectiveness of MeTILDA in creating Pitch Art using the perceptual scale.

The AGE Presents Introduction to Geroscience video lecture series is a collection of high-quality didactic video lectures and associated teaching materials focused on foundational topics in aging biology. The videos are made freely available on YouTube and are targeted toward an audience familiar with concepts learned in the first year of a college undergraduate biology/biomedical major. Members of the American Aging Association also receive the original lecture slides and lecture notes, with additional course materials to be developed in the future. We expect that these lectures will enhance understanding of geroscience among the general public while also providing tools that educators can use in the classroom for high school, undergraduate, and graduate level curricula.

Purpose To assess which factors in the lives and disease of patients with glaucoma affect their adherence to topical glaucoma therapy and the quantitative significance of this effect. To assess qualitatively the most influential barriers to adherence from the perspective of the patient. Design Multicenter, prospective, cross-sectional pilot study. Participants A total of 145 patients, attending outpatient metropolitan glaucoma clinics in Sydney, Australia, who were prescribed topical glaucoma medications. Methods A structured interview-based questionnaire was conducted with 145 individuals using glaucoma eye drops that had been prescribed at least 2 weeks previously. The questionnaire involved 2 novel questions on adherence, 29 questions on factors identified or postulated in the literature as affecting adherence for quantitative analysis, and 1 open-response question on patient-identified causes of nonadherence for qualitative analysis. This questionnaire represents the broadest coverage of factors hypothesized to affect adherence in a single study in the glaucoma medication adherence literature to date. Main Outcome Measures Adherence rate, risk factors for poor adherence, and patient-identified barriers to adherence. Results In response to the question “How many days have you missed a drop in the last 2 weeks,” 69.7% of patients reported total adherence. Four factors were significantly related to an increased likelihood of reporting having missed drops in the last 2 weeks. These were difficulty applying drops (odds ratio [OR], 2.35; 95% confidence interval [CI], 1.02–5.44; P Conclusions There is a significant proportion of patients taking their topical glaucoma medications less often than prescribed. Adherence to topical glaucoma therapies is negatively correlated to several factors: difficulty applying drops, a past or current diagnosis of depression, poor self-rating of own memory, and poor self-rating of own motivation. These may prove useful in designing interventions to improve adherence in these patients.

Mutations accumulate within somatic cells and have been proposed to contribute to aging. It is unclear what level of mutation burden may be required to consistently reduce cellular lifespan. Human cancers driven by a mutator phenotype represent an intriguing model to test this hypothesis, since they carry the highest mutation burdens of any human cell. However, it remains technically challenging to measure the replicative lifespan of individual mammalian cells. Here, we modeled the consequences of cancer-related mutator phenotypes on lifespan using yeast defective for mismatch repair (MMR) and/or leading strand (Polε) or lagging strand (Polδ) DNA polymerase proofreading. Only haploid mutator cells with significant lifetime mutation accumulation (MA) exhibited shorter lifespans. Diploid strains, derived by mating haploids of various genotypes, carried variable numbers of fixed mutations and a range of mutator phenotypes. Some diploid strains with fewer than two mutations per megabase displayed a 25% decrease in lifespan, suggesting that moderate numbers of random heterozygous mutations can increase mortality rate. As mutation rates and burdens climbed, lifespan steadily eroded. Strong diploid mutator phenotypes produced a form of genetic anticipation with regard to aging, where the longer a lineage persisted, the shorter lived cells became. Using MA lines, we established a relationship between mutation burden and lifespan, as well as population doubling time. Our observations define a threshold of random mutation burden that consistently decreases cellular longevity in diploid yeast cells. Many human cancers carry comparable mutation burdens, suggesting that while cancers appear immortal, individual cancer cells may suffer diminished lifespan due to accrued mutation burden.

An increase in cell size with age is a characteristic feature of replicative aging in budding yeast. Deletion of the gene encoding Whi5 results in shortened duration of G1 and reduced cell size, and has been previously suggested to increase replicative lifespan. Upon careful analysis of multiple independently derived haploid and homozygous diploid whi5Δ mutants, we find no effect on lifespan, but we do confirm the reduction in cell size. We suggest that instead of antagonizing lifespan, the elongated G1 phase of the cell cycle during aging may actually play an important role in allowing aged cells time to repair accumulating DNA damage. Keywords: Cell cycle regulation, Replicative aging, Saccharomyces cerevisiae

The question of why and how some species or individuals within a population live longer than others is among the most important questions in the biology of aging. A particularly useful model to understand the genetic basis and selective forces acting on the plasticity of lifespan are closely related species or ecologically diverse individuals of the same species widely different in lifespan. Here, we analyzed 76 diverse wild isolates of two closely related budding yeast species Saccharomyces cerevisiae and Saccharomyces paradoxus and discovered a diversity of natural intra-species lifespan variation. We sequenced the genomes of these organisms and analyzed how their replicative lifespan is shaped by nutrients and transcriptional and metabolite patterns. We identified sets of genes and metabolites to regulate aging pathways, many of which have not been previously associated with lifespan regulation. We also identified and characterized long-lived strains with elevated intermediary metabolites and differentially regulated genes for NAD metabolism and the control of epigenetic landscape through chromatin silencing. Our data further offer insights into the evolution and mechanisms by which caloric restriction regulates lifespan by modulating the availability of nutrients without decreasing fitness. Overall, our study shows how the environment and natural selection interact to shape diversity of lifespan.

The yeast genome becomes unstable during stress, which often results in adaptive aneuploidy, allowing rapid activation of protective mechanisms that restore cellular homeostasis. In this study, we performed a genetic screen in Saccharomyces cerevisiae to identify genome adaptations that confer resistance to tunicamycin-induced endoplasmic reticulum (ER) stress. Whole-genome sequencing of tunicamycin-resistant mutants revealed that ER stress resistance correlated significantly with gains of chromosomes II and XIII. We found that chromosome duplications allow adaptation of yeast cells to ER stress independently of the unfolded protein response, and that the gain of an extra copy of chromosome II alone is sufficient to induce protection from tunicamycin. Moreover, the protective effect of disomic chromosomes can be recapitulated by overexpression of several genes located on chromosome II. Among these genes, overexpression of UDP-N-acetylglucosamine-1-P transferase (ALG7), a subunit of the 20S proteasome (PRE7), and YBR085C-A induced tunicamycin resistance in wild-type cells, whereas deletion of all three genes completely reversed the tunicamycin-resistance phenotype. Together, our data demonstrate that aneuploidy plays a critical role in adaptation to ER stress by increasing the copy number of ER stress protective genes. While aneuploidy itself leads to proteotoxic stress, the gene-specific effects of chromosome II aneuploidy counteract the negative effect resulting in improved protein folding.

Purpose: Multiple myeloma is an insidious haematological malignancy characterised by monoclonal proliferation of plasma cells in the bone marrow. Extramedullary plasmacytoma is a rare manifestation of multiple myeloma and usually occurs in the upper respiratory tract. Orbital involvement is particularly uncommon, but may be associated with devastating visual impairment and poor clinical outcomes. Therefore, this article aims to highlight the need for multidisciplinary management of orbital extramedullary plasmacytoma. Methods: This is a retrospective observational case series of five patients. All presented to the authors for management of orbital extramedullary plasmacytomas from 2004 to 2015 at Prince of Wales and Mater Hospitals in Sydney, Australia. Medical records were reviewed for pertinent information including demographics, disease features, management strategy, and clinical progress. The study met Medical Ethics Board standards and is in accordance with the Helsinki Agreements. Results: This case series of five patients underscores the poor prognosis of orbital extramedullary plasmacytoma. Despite aggressive multidisciplinary management, four of these five patients succumbed to their illness during the study period. However, multidisciplinary management did manage to minimise symptoms and preserve quality of life. Conclusions: On a case-by-case basis, patients may derive palliative benefit from orbital surgery in conjunction with radiotherapy and chemotherapy. Orbital surgeons are encouraged to work within a multidisciplinary framework of medical specialists, including haematologists and radiation oncologists, when determining the optimal management plan in cases of orbital extramedullary plasmacytoma.

We have developed a catalytic method for the hydroalkylation of allenes using alkyl triflates as electrophiles and silane as a hydride source. The reaction has an excellent substrate scope and is compatible with a wide range of functional groups, including esters, aryl halides, aryl boronic esters, sulfonamides, alkyl tosylates, and alkyl bromides. We found evidence for a reaction mechanism that involves unusual dinuclear copper ally complexes as catalytic intermediates. The unusual structure of these complexes provides a rationale for their unexpected reactivity.

The mechanistic target of rapamycin (mTOR) is a central regulator of growth and proliferation and mTOR inhibition is a promising therapy for a variety of diseases and disorders. Inhibition of mTOR complex I (mTORC1) with rapamycin delays aging and increases healthy longevity in laboratory animals and is used clinically at high doses to prevent organ transplant rejection and to treat some forms of cancer. Clinical use of rapamycin is associated with several unwanted side effects, however, and several strategies are being taken to identify mTORC1 inhibitors with fewer side effects. We describe here a yeast-based growth assay that can be used to screen for novel inhibitors of mTORC1. By testing compounds using a wild-type strain and isogenic cells lacking either TOR1 or FPR1, we can resolve not only whether a compound is an inhibitor of mTORC1 but also whether the inhibitor acts through a mechanism similar to rapamycin by binding Fpr1. Using this assay, we show that rapamycin derivatives behave similarly to rapamycin, while caffeine and the ATP competitive inhibitors Torin 1 and GSK2126458 are mTORC1 inhibitors in yeast that act independently of Fpr1. Some mTOR inhibitors in mammalian cells do not inhibit mTORC1 in yeast, and several nutraceutical compounds were not found to specifically inhibit mTOR but resulted in a general inhibition of yeast growth. Our screening method holds promise as a means of effectively assaying drug libraries for mTOR-inhibitory molecules in vivo that may be adapted as novel treatments to fight diseases and extend healthy longevity.

Mutations affecting DNA polymerase exonuclease domains or mismatch repair (MMR) generate “mutator” phenotypes capable of driving tumorigenesis. Cancers with both defects exhibit an explosive increase in mutation burden that appears to reach a threshold, consistent with selection acting against further mutation accumulation. In Saccharomyces cerevisiae haploid yeast, simultaneous defects in polymerase proofreading and MMR select for “antimutator” mutants that suppress the mutator phenotype. We report here that spontaneous polyploids also escape this “error-induced extinction” and routinely outcompete antimutators in evolved haploid cultures. We performed similar experiments to explore how diploid yeast adapt to the mutator phenotype. We first evolved cells with homozygous mutations affecting polymerase δ proofreading and MMR, which we anticipated would favor tetraploid emergence. While tetraploids arose with a low frequency, in most cultures, a single antimutator clone rose to prominence carrying biallelic mutations affecting the polymerase mutator alleles. Variation in mutation rate between subclones from the same culture suggests that there exists continued selection pressure for additional antimutator alleles. We then evolved diploid yeast modeling MMR-deficient cancers with the most common heterozygous exonuclease domain mutation (POLE-P286R). Although these cells grew robustly, within 120 generations, all subclones carried truncating or nonsynonymous mutations in the POLE-P286R homologous allele (pol2-P301R) that suppressed the mutator phenotype as much as 100-fold. Independent adaptive events in the same culture were common. Our findings suggest that analogous tumor cell populations may adapt to the threat of extinction by polyclonal mutations that neutralize the POLE mutator allele and preserve intratumoral genetic diversity for future adaptation.

DNA polymerase (Pol) proofreading and mismatch repair (MMR) defects produce “mutator” phenotypes capable of driving tumorigenesis. “Ultra-mutated” cancers with defects in both pathways exhibit an explosive increase in point mutation burden that appears to reach an upper limit of ∼250 mutations/Mb, which may be evidence for negative selection. Simultaneous defects in proofreading and MMR drive error-induced extinction ( EEX ) of haploid yeast. Some yeast mutants escape extinction through antimutator mutations that suppress the mutator phenotype. We report here that other yeast mutants escape by spontaneous polyploidization. We sought to compare these two adaptive strategies during the evolution of haploid and diploid mutators. We first evolved 89 independently isolated haploid mutator strains with mutation rates an order of magnitude below the lethal threshold. Polyploid cells overtook nearly every culture. In a similar manner, we evolved strong diploid mutators, but found only a single tetraploid emerged after ∼250 cellular generations. Antimutators dominated these late passage cultures and were present after only 30-40 cellular generations. Whole genome sequencing of independent isolates from the same culture allowed us to construct phylogenetic trees that revealed that a single subclone swept through each culture carrying multiple antimutator mutations affecting the mutator polymerase. Variation in mutation rate between subclones from the same culture suggests some strains carry additional antimutator alleles in other genes. Our findings in diploid mutator yeast suggest that mutator-driven cancer cells may also adapt to the threat of extinction by accumulating multiple antimutator alleles that cooperatively reduce mutation rate to tolerable levels. Author summary “Mutator” tumor cells that cannot correct DNA replication errors exhibit an extremely high mutation rate that accelerates their evolution. But this gamble puts them at risk for extinctiondue to the accumulation of harmful mutations. Mutator yeast cells escape extinction through “antimutator” mutations that lower mutation rate. We discovered that yeast cells also adapt by duplicating their genome. To understand which adaptation may emerge in mutator-driven tumors, we evolved haploid and diploid mutator yeast cells by long-term propagation. Haploid mutators primarily adapted by genome duplication, thereby protecting themselves from recessive lethal mutations. In contrast, diploid mutators evolved by acquiring multiple antimutator mutations. Our results suggest that mutator-driven tumors may similarly accumulate combinations of mutations that attenuate their high mutation rates.

To assess which factors in the lives and disease of patients with glaucoma affect their adherence to topical glaucoma therapy and the quantitative significance of this effect. To assess qualitatively the most influential barriers to adherence from the perspective of the patient.Multicenter, prospective, cross-sectional pilot study.A total of 145 patients, attending outpatient metropolitan glaucoma clinics in Sydney, Australia, who were prescribed topical glaucoma medications.A structured interview-based questionnaire was conducted with 145 individuals using glaucoma eye drops that had been prescribed at least 2 weeks previously. The questionnaire involved 2 novel questions on adherence, 29 questions on factors identified or postulated in the literature as affecting adherence for quantitative analysis, and 1 open-response question on patient-identified causes of nonadherence for qualitative analysis. This questionnaire represents the broadest coverage of factors hypothesized to affect adherence in a single study in the glaucoma medication adherence literature to date.Adherence rate, risk factors for poor adherence, and patient-identified barriers to adherence.In response to the question "How many days have you missed a drop in the last 2 weeks," 69.7% of patients reported total adherence. Four factors were significantly related to an increased likelihood of reporting having missed drops in the last 2 weeks. These were difficulty applying drops (odds ratio [OR], 2.35; 95% confidence interval [CI], 1.02-5.44; P0.05), a past or current diagnosis of depression (OR, 3.61; 95% CI, 1.53-8.52; P0.01), patient self-rating of own memory ≤ 7 of 10 (OR, 3.15; 95% CI, 1.36-7.30; P0.01), and self-reported motivation score ≤ 6 of 10 (OR, 10.94; 95% CI, 3.00-39.81; P0.01). Patient understanding of glaucoma, ethnicity, and socioeconomic status were among the 25 factors found not to have a statistically significant correlation with adherence.There is a significant proportion of patients taking their topical glaucoma medications less often than prescribed. Adherence to topical glaucoma therapies is negatively correlated to several factors: difficulty applying drops, a past or current diagnosis of depression, poor self-rating of own memory, and poor self-rating of own motivation. These may prove useful in designing interventions to improve adherence in these patients.

The budding yeast has served as a useful model organism in aging studies, leading to the identification of genetic determinants of longevity, many of which are conserved in higher eukaryotes. However, factors that promote longevity in a laboratory setting often have severe fitness disadvantages in the wild. To obtain an unbiased view on longevity regulation, we analyzed how a replicative lifespan is shaped by transcriptional, translational, metabolic, and morphological factors across 22 wild-type Saccharomyces cerevisiae isolates. We observed significant differences in lifespan across these strains and found that their longevity is strongly associated with up-regulation of oxidative phosphorylation and respiration and down-regulation of amino- acid and nitrogen compound biosynthesis. As calorie restriction and TOR signaling also extend the lifespan by adjusting many of the identified pathways, the data suggest that the natural plasticity of yeast lifespan is shaped by the processes that not only do not impose cost on fitness, but also are amenable to dietary intervention. A new study pinpoints a consistent set of genes and pathways underlying variations in yeast lifespan. Vadim Gladyshev at Harvard Medical School and co-workers analyzed 22 Saccharomyces cerevisiae yeast strains with diverse lifespans and habitats, looking to identify genomic signatures associated with natural variations in longevity. They observed a number of factors that characterized the longest-lived strains, including the upregulation of aerobic respiration, and found that interactions between genes and the environment were key. They also showed that factors associated with increased longevity in yeast strains do not necessarily degrade the fitness of those strains in the wild, and that longevity can be influenced through diet. The study thus paints a more complete picture of how environmental factors trigger changes—some hard–wired in the genome—that have real consequences on aging and longevity.

Global development organizations rely on the essential affordances provided by both paper and digital materials to navigate hurdles posed by poor infrastructure, low connectivity, linguistic differences, and other socioeconomic constraints that render communication and collaboration challenging. This paper examines the collaborative practices around paper-digital workflows within global development organizations operating in low-resource environments. We use a mixed methods approach to gather data from 23 organizations in 16 countries. Our findings show the tensions that arise between the ubiquitousness of paper and the desirability of digitized data, and highlight the challenges associated with transitioning information several times between paper and digital materials. We also reveal design opportunities for new tools to bridge the gap between paper-based and digital information in low-resource settings. Finally, we contribute a nuanced understanding of the cross-cultural and infrastructural challenges that influence the paper-digital lifecycle. Our findings will be useful for researchers and practitioners interested in understanding or participating in the workflows that drive global development.