OASIS: online application for the survival analysis of lifespan assays performed in aging research

Influence of α-lipoic acid on longevity and stress resistance in Drosophila melanogaster fed with a high-fat diet

Consumption of a high-fat diet is accompanied by the risks of obesity and early onset of age-associated complications for which dietary interventions are imperative to combat. α-lipoic acid has been shown to hinder diet-induced obesity and induce lifespan-extending efficacy in model organisms. In this study, α-lipoic acid was investigated for its efficacy in improving lifespan and stress resistance in the Canton-S strain of Drosophila melanogaster fed with a high-fat diet. Furthermore, as mating status significantly impacts survival in fruit flies, flies were reared in two experimental groups-group one, in which males and females were bred together, and group two, in which males and females were bred separately. In group one, α-lipoic acid improved the mean lifespan, reduced the fecundity of females, and reduced the mean body weight of flies at a dose range of 2-2.5 mM, respectively. In group two, α-lipoic acid improved the mean lifespan, reduced the fecundity of females, and reduced the mean body weight of flies at a dose range of 1-2.5 mM, respectively. Improved climbing efficiency was observed with α-lipoic acid at the dose range of 1.5-2.5 mM in flies of group one and 1-2.5 mM in flies of group two, respectively. Administration of α-lipoic acid improved resistance to oxidative stress in only female flies of group one at 2.5 mM, whereas in group two, both male and female flies exhibited enhanced resistance to oxidative stress with α-lipoic acid at a dose range of 2-2.5 mM, respectively. Male and female flies of only group one showed improved resistance to heat shock stress with α-lipoic acid at a dose range of 2-2.5 mM. Only female flies of group two exhibited a slight improvement in recovery time following cold shock with α-lipoic acid only at 2.5 mM. No significant change in resistance to starvation stress was observed with any dose of α-lipoic acid in either group of flies. To summarize, data from this study suggested a probable dose and gender-dependent efficacy of α-lipoic acid in flies fed with a high-fat diet, which was significantly influenced by the mating status of flies due to varied rearing conditions.

HLH-30/TFEB mediates sexual dimorphism in immunity in Caenorhabditis elegans

Sexual dimorphism affects various biological functions, including immune responses. However, the mechanisms by which sex alters immunity remain largely unknown. Using Caenorhabditis elegans as a model species, we showed that males exhibit enhanced immunity against various pathogenic bacteria through the upregulation of HLH-30 (Helix Loop Helix 30/TFEB (transcription factor EB)), a transcription factor crucial for macroautophagy/autophagy. Compared with hermaphroditic C. elegans, males displayed increased activity of HLH-30/TFEB, which contributed to enhanced antibacterial immunity. atg-2 (AuTophaGy (yeast Atg homolog) 2) upregulated by HLH-30/TFEB mediated increased immunity in male C. elegans. Thus, the males appear to be equipped with enhanced HLH-30/TFEB-mediated autophagy, which increases pathogen resistance, and this may functionally prolong mate-searching ability with reduced risk of infection.Abbreviations: atg-2: AuTophaGy (yeast Atg homolog) 2; FUDR: 5-fluoro-2'-deoxyuridine; GSEA: gene set enrichment analysis; HLH-30: Helix Loop Helix 30; LC3: microtubule associated protein 1 light chain 3; NGM: nematode growth media; RNA-seq: RNA sequencing; SEM: standard error of the mean; TFEB: transcription factor EB; WT: wild-type.

Macauba (Acrocomia aculeata) pulp oil reduces fat accumulation and enhances the lifespan of Caenorhabditis elegans at low temperatures via fat-1- and fat-7-dependent pathway

Macauba (Acrocomia aculeata) is a Brazilian palm tree whose oil in the pulp is rich in oleic acid and carotenoids. However, its physiological function remains unknown. This study aimed to investigate the effects of macauba pulp oil (MPO) on the metabolic link between lipid metabolism and lifespan using Caenorhabditis elegans (C. elegans). C. elegans were treated with 5.0 mg/mL of MPO for analyzing triglyceride and glycerol accumulation, fatty acid profile, gene expression of lipid and oxidative metabolism proteins under cold (4°C) stress conditions, and lifespan analysis under stress conditions such as cold (4°C), heat (37°C), and oxidative (paraquat) stress. MPO significantly suppressed fat accumulation and increased glycerol (a lipolysis index) and the lifespan of C. elegans at low temperature (4°C). This was accompanied by decreased mRNA levels of the genes involved in lipogenesis (spb-1 and pod-2) and increased levels of the genes involved in fatty acid β-oxidation (acs-2 and nhr-49) and fat mobilization genes (hosl-1 and aak-2). Additionally, MPO treatment modulated fatty acid pools in C. elegans at low temperatures in that MPO treatment decreased saturated fatty acid levels and shifted the fatty acid profile to long-chain fatty acids. Moreover, the effect of MPO on fat accumulation at low temperatures was abolished in fat-7 mutants, whereas both fat-1 and fat-7 contribute, at least in part, to MPO-elevated survival of C. elegans under cold conditions. PRACTICAL APPLICATION: The results obtained in the present study may contribute to the understanding of the health benefits of consuming macauba pulp oil and consequently stimulate economic growth and the industrial application of this new type of oil, which may result in the creation of new jobs and increased value of small producers.

Dietary fiber supplementation increases Drosophila melanogaster lifespan and gut microbiota diversity

Dietary fiber has been shown to have multiple health benefits, including a positive effect on longevity and the gut microbiota. In the present study, Drosophila melanogaster has been chosen as an in vivo model organism to study the health effects of dietary fiber supplementation (DFS). DFS extended the mean half-life of male and female flies, but the absolute lifespan only increased in females. To reveal the underlying mechanisms, we examined the effect of DFS on gut microbiota diversity and abundance, local gut immunity, and the brain proteome. A significant difference in the gut microbial community was observed between groups with and without fiber supplementation, which reduced the gut pathogenic bacterial load. We also observed an upregulated expression of dual oxidase and a modulated expression of Attacin and Diptericin genes in the gut of older flies, possibly delaying the gut dysbiosis connected to the age-related gut immune dysfunction. Brain proteome analysis showed that DFS led to the modulation of metabolic processes connected to mitochondrial biogenesis, the RhoV-GTPase cycle, organelle biogenesis and maintenance, membrane trafficking and vesicle-mediated transport, possibly orchestrated through a gut-brain axis interaction. Taken together, our study shows that DFS can prolong the half-life and lifespan of flies, possibly by promoting a healthier gut environment and delaying the physiological dysbiosis that characterizes the ageing process. However, the RhoV-GTPase cycle at the brain level may deserve more attention in future studies.

Cytosolic Ribosomal Protein Haploinsufficiency affects Mitochondrial Morphology and Respiration

The interplay between ribosomal protein composition and mitochondrial function is essential for sustaining energy homeostasis. Precise stoichiometric production of ribosomal proteins is crucial to maximize protein synthesis efficiency while reducing the energy costs to the cell. However, the impact of this balance on mitochondrial ATP generation, morphology and function remains unclear. Particularly, the loss of a single copy ribosomal protein gene is observed in Mendelian disorders like Diamond Blackfan Anemia and is common in somatic tumors, yet the implications of this imbalance on mitochondrial function and energy dynamics are still unclear. In this study, we investigated the impact of haploinsufficiency for four ribosomal protein genes implicated in ribosomopathy disorders (rps-10, rpl-5, rpl-33, rps-23) in Caenorhabditis elegans and corresponding reductions in human lymphoblast cells. Our findings uncover significant, albeit variably penetrant, mitochondrial morphological differences across these mutants, alongside an upregulation of glutathione transferases, and SKN-1 dependent increase in oxidative stress resistance, indicative of increased ROS production. Specifically, loss of a single copy of rps-10 in C. elegans led to decreased mitochondrial activity, characterized by lower energy levels and reduced oxygen consumption. A similar reduction in mitochondrial activity and energy levels was observed in human leukemia cells with a 50% reduction in RPS10 transcript levels. Importantly, we also observed alterations in the translation efficiency of nuclear and mitochondrial electron transport chain components in response to reductions in ribosomal protein genes' expression in both C. elegans and human cells. This suggests a conserved mechanism whereby the synthesis of components vital for mitochondrial function are adjusted in the face of compromised ribosomal machinery. Finally, mitochondrial membrane and cytosolic ribosomal components exhibited significant covariation at the RNA and translation efficiency level in lymphoblastoid cells across a diverse group of individuals, emphasizing the interplay between the protein synthesis machinery and mitochondrial energy production. By uncovering the impact of ribosomal protein haploinsufficiency on the translation efficiency of electron transport chain components, mitochondrial physiology, and the adaptive stress responses, we provide evidence for an evolutionarily conserved strategy to safeguard cellular functionality under genetic stress.

Maria JP, Tablante KIG, Tiam-Lee JGA, Sison MCC, Medina PMB. Effect of Garcinia binucao Crude Leaf Extract Supplementation on Lifespan of Drosophila melanogaster Chronically Exposed to Alcohol

Background

Consumption and abuse of alcohol remains a significant cause of concern worldwide. Furthermore, there is evidence of the association between chronic alcohol use and reduced life expectancy.

Objectives

To study the effects of Garcinia binucao extract (GBE) supplementation on lifespan of Drosophila melanogaster, in the presence or absence of chronic alcohol exposure.

Methods

D. melanogaster was mass cultured and given GBE supplementation in high (1 mg/mL) and low (200 µg/mL) sublethal doses. D. melanogaster flies were divided into groups - with and without chronic alcohol exposure, and their respective lifespans were monitored.

Results

In D. melanogaster without alcohol exposure, mean lifespan was highest in the control flies (38.15 days), followed by high-dose GBE (34.42 days), low-dose GBE (33.24 days), and DMSO (22.29 days). In D. melanogaster chronically exposed to alcohol, the longest mean lifespan was observed in flies treated with high-dose GBE (33.80 days), followed by low-dose GBE (33.63 days), the DMSO group (30.30), and the control group (29.65 days), but the differences were not statistically significant. Comparing groups with and without chronic alcohol exposure, the mean lifespan of the control group chronically exposed to alcohol significantly decreased by 9.51 days (p < 0.05). In GBE treatment groups, mean lifespan significantly decreased by 0.82 days in high-dose set-up (p < 0.05), and significantly increased by 0.39 days in the low-dose set-up (p < 0.05) upon chronic alcohol exposure.

Conclusion

Garcinia binucao extract supplementation ameliorated the observed reduction in lifespan of Drosophila melanogaster chronically exposed to alcohol.

Leaf extract of Garcinia atroviridis promotes anti-heat stress and antioxidant effects in Caenorhabditis elegans

Introduction: Garcinia atroviridis has been used for traditional medicines, healthy foods and tea. The chemical compositions and biological activities of fruit, stem bark and root have been widely studied. However, the phytochemical components and the biological activities in Garcinia atroviridis leaves (GAL) are limited. This research aims to study the phytochemical components and the stress resistance effects of GAL in Caenorhabditis elegans (C. elegans). Methods: To investigate the chemical components and antioxidant activities of GAL extract, the ethanol extract was characterized by liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF MS) analysis and C. elegans was used to evaluate the effects of GAL extracts on longevity and stress resistance. Results and discussion: The results revealed that the ethanol extract of GAL possesses free radical scavenging activities. Furthermore, GAL extract increased the lifespan of C. elegans by 6.02%, 15.26%, and 12.75% at concentrations of 25, 50, and 100 μg/mL, respectively. GAL extract exhibited improved stress resistance under conditions of heat and hydrogen peroxide-induced stress. The survival rates of GAL extract-treated worms were significantly higher than those of untreated worms, and GAL extract reduced reactive oxygen species (ROS) accumulation. Additionally, GAL extract treatment upregulated the expression of stress resistance-associated genes, including gst-4, sod-3, skn-1, and hsp16.2. GAL extract supplementation alleviated stress and enhanced longevity by inducing stress-related genes in C. elegans. The observed effects of GAL extracts may be attributed to the stimulation of oxidant enzymes mediated through DAF-16/FOXO and SKN-1/NRF2, as well as the enhancement of thermal defense in C. elegans. Collectively, this study provides the first evidence of the antioxidant activities of GAL and elucidates the underlying mechanisms of stress resistance.

The Muscleblind-like protein MBL-1 regulates microRNA expression in Caenorhabditis elegans through an evolutionarily conserved autoregulatory mechanism

The Muscleblind-like (MBNL) family is a highly conserved set of RNA-binding proteins (RBPs) that regulate RNA metabolism during the differentiation of various animal tissues. Functional insufficiency of MBNL affects muscle and central nervous system development, and contributes to the myotonic dystrophies (DM), a set of incurable multisystemic disorders. Studies on the regulation of MBNL genes are essential to provide insight into the gene regulatory networks controlled by MBNL proteins and to understand how dysregulation within these networks causes disease. In this study, we demonstrate the evolutionary conservation of an autoregulatory mechanism that governs the function of MBNL proteins by generating two distinct protein isoform types through alternative splicing. Our aim was to further our understanding of the regulatory principles that underlie this conserved feedback loop in a whole-organismal context, and to address the biological significance of the respective isoforms. Using an alternative splicing reporter, our studies show that, during development of the Caenorhabditis elegans central nervous system, the orthologous mbl-1 gene shifts production from long protein isoforms that localize to the nucleus to short isoforms that also localize to the cytoplasm. Using isoform-specific CRISPR/Cas9-generated strains, we showed that expression of short MBL-1 protein isoforms is required for healthy neuromuscular function and neurodevelopment, while expression of long MBL-1 protein isoforms is dispensable, emphasizing a key role for cytoplasmic functionalities of the MBL-1 protein. Furthermore, RNA-seq and lifespan analyses indicated that short MBL-1 isoforms are crucial regulators of miRNA expression and, in consequence, required for normal lifespan. In conclusion, this study provides support for the disruption of cytoplasmic RNA metabolism as a contributor in myotonic dystrophy and paves the way for further exploration of miRNA regulation through MBNL proteins during development and in disease models.

Automation of Caenorhabditis elegans lifespan assay using a simplified domain synthetic image-based neural network training strategy

Performing lifespan assays with Caenorhabditis elegans (C. elegans) nematodes manually is a time consuming and laborious task. Therefore, automation is necessary to increase productivity. In this paper, we propose a method to automate the counting of live C. elegans using deep learning. The survival curves of the experiment are obtained using a sequence formed by an image taken on each day of the assay. Solving this problem would require a very large labeled dataset; thus, to facilitate its generation, we propose a simplified image-based strategy. This simplification consists of transforming the real images of the nematodes in the Petri dish to a synthetic image, in which circular blobs are drawn on a constant background to mark the position of the C. elegans. To apply this simplification method, it is divided into two steps. First, a Faster R-CNN network detects the C. elegans, allowing its transformation into a synthetic image. Second, using the simplified image sequence as input, a regression neural network is in charge of predicting the count of live nematodes on each day of the experiment. In this way, the counting network was trained using a simple simulator, avoiding labeling a very large real dataset or developing a realistic simulator. Results showed that the differences between the curves obtained by the proposed method and the manual curves are not statistically significant for either short-lived N2 (p-value log rank test 0.45) or long-lived daf-2 (p-value log rank test 0.83) strains.

Autophagy impairment and lifespan reduction caused by Atg1 RNAi or Atg18 RNAi expression in adult fruit flies (Drosophila melanogaster)

Autophagy, an autophagosome and lysosome-based eukaryotic cellular degradation system, has previously been implicated in lifespan regulation in different animal models. In this report, we show that expression of the RNAi transgenes targeting the transcripts of the key autophagy genes Atg1 or Atg18 in adult fly muscle or glia does not affect the overall levels of autophagosomes in those tissues and does not change the lifespan of the tested flies but the lifespan reduction phenotype has become apparent when Atg1 RNAi or Atg18 RNAi is expressed ubiquitously in adult flies or after autophagy is eradicated through the knockdown of Atg1 or Atg18 in adult fly adipocytes. Lifespan reduction was also observed when Atg1 or Atg18 was knocked down in adult fly enteroblasts and midgut stem cells. Overexpression of wild-type Atg1 in adult fly muscle or adipocytes reduces the lifespan and causes accumulation of high levels of ubiquitinated protein aggregates in muscles. Our research data have highlighted the important functions of the key autophagy genes in adult fly adipocytes, enteroblasts, and midgut stem cells and their undetermined roles in adult fly muscle and glia for lifespan regulation.

Easy C. elegans Worm Lifespan Plotting and Statistics with WLSplot

WLSplot is an R package used to easily analyze lifespan survival data, and display results graphically as a survival curve with useful labels and statistical information auto-generated from the data and added to the graph, within a single function. It is designed primarily with Caenorhabditis elegans lifespan data in mind initially but can easily be used for other types of survival data. The WLSplot GitHub repository provides a blank template spreadsheet to be used for collecting lifespan data, instructions on how to install and run WLSplot, and examples covering RNAi, Genotype, or Drug lifespan experimental set-ups. WLSplot can analyze and plot multiple experiments in bulk while correctly italicizing worm gene names and adding asterisks and p-values to the plot legend when a significantly different lifespan from the designated control lifespan is seen. This is returned as an editable scalable vector graphics (svg) file for each output, and WLSplot can also return the summary of the directly plotted data so that the researcher can do their own further manipulation, in addition to being able to edit the output svg files.

Rege-1 promotes C. elegans survival by modulating IIS and TOR pathways

Metabolic pathways are known to sense the environmental stimuli and result in physiological adjustments. The responding processes need to be tightly controlled. Here, we show that upon encountering P. aeruginosa, C. elegans upregulate the transcription factor ets-4, but this upregulation is attenuated by the ribonuclease, rege-1. As such, mutants with defective REGE-1 ribonuclease activity undergo ets-4-dependent early death upon challenge with P. aeruginosa. Furthermore, mRNA-seq analysis revealed associated global changes in two key metabolic pathways, the IIS (insulin/IGF signaling) and TOR (target of rapamycin) kinase signaling pathways. In particular, failure to degrade ets-4 mRNA in activity-defective rege-1 mutants resulted in upregulation of class II longevity genes, which are suppressed during longevity, and activation of TORC1 kinase signaling pathway. Genetic inhibition of either pathway way was sufficient to abolish the poor survival phenotype in rege-1 worms. Further analysis of ETS-4 ChIP data from ENCODE and characterization of one upregulated class II gene, ins-7, support that the Class II genes are activated by ETS-4. Interestingly, deleting an upregulated Class II gene, acox-1.5, a peroxisome β-oxidation enzyme, largely rescues the fat lost phenotype and survival difference between rege-1 mutants and wild-types. Thus, rege-1 appears to be crucial for animal survival due to its tight regulation of physiological responses to environmental stimuli. This function is reminiscent of its mammalian ortholog, Regnase-1, which modulates the intestinal mTORC1 signaling pathway.

Mitochondrial aconitase suppresses immunity by modulating oxaloacetate and the mitochondrial unfolded protein response

Accumulating evidence indicates that mitochondria play crucial roles in immunity. However, the role of the mitochondrial Krebs cycle in immunity remains largely unknown, in particular at the organism level. Here we show that mitochondrial aconitase, ACO-2, a Krebs cycle enzyme that catalyzes the conversion of citrate to isocitrate, inhibits immunity against pathogenic bacteria in C. elegans. We find that the genetic inhibition of aco-2 decreases the level of oxaloacetate. This increases the mitochondrial unfolded protein response, subsequently upregulating the transcription factor ATFS-1, which contributes to enhanced immunity against pathogenic bacteria. We show that the genetic inhibition of mammalian ACO2 increases immunity against pathogenic bacteria by modulating the mitochondrial unfolded protein response and oxaloacetate levels in cultured cells. Because mitochondrial aconitase is highly conserved across phyla, a therapeutic strategy targeting ACO2 may eventually help properly control immunity in humans.

A Caenorhabditis elegans model of autosomal dominant adult-onset neuronal ceroid lipofuscinosis identifies ethosuximide as a potential therapeutic

Autosomal dominant adult-onset neuronal ceroid lipofuscinosis (ANCL) is a rare neurodegenerative disorder characterized by progressive dementia and premature death. Four ANCL-causing mutations have been identified, all mapping to the DNAJC5 gene that encodes cysteine string protein α (CSPα). Here, using Caenorhabditis elegans, we describe an animal model of ANCL in which disease-causing mutations are introduced into their endogenous chromosomal locus, thereby mirroring the human genetic disorder. This was achieved through CRISPR/Cas9-mediated gene editing of dnj-14, the C. elegans ortholog of DNAJC5. The resultant homozygous ANCL mutant worms exhibited reduced lifespans and severely impaired chemotaxis, similar to isogenic dnj-14 null mutants. Importantly, these phenotypes were also seen in balanced heterozygotes carrying one wild-type and one ANCL mutant dnj-14 allele, mimicking the heterozygosity of ANCL patients. We observed a more severe chemotaxis phenotype in heterozygous ANCL mutant worms compared with haploinsufficient worms lacking one copy of CSP, consistent with a dominant-negative mechanism of action. Additionally, we provide evidence of CSP haploinsufficiency in longevity, as heterozygous null mutants exhibited significantly shorter lifespan than wild-type controls. The chemotaxis phenotype of dnj-14 null mutants was fully rescued by transgenic human CSPα, confirming the translational relevance of the worm model. Finally, a focused compound screen revealed that the anti-epileptic drug ethosuximide could restore chemotaxis in dnj-14 ANCL mutants to wild-type levels. This suggests that ethosuximide may have therapeutic potential for ANCL and demonstrates the utility of this C. elegans model for future larger-scale drug screening.

Photo-and thermo-regulation by photonic crystals for extended longevity of C. elegans

Methods allowing light energy to be modulated in a controllable fashion are potentially important for finding the correlation between light-related environmental factors and aging-related lifespan. Here, we report photo- and thermo-regulation based on photonic crystals (PCs) for extended longevity of C. elegans. We show that PCs can function as a regulator of visible spectrum to tune photonic energy received by C.elegans. We provide direct evidence that lifespan depends on photonic energy, and the use of PCs reflecting blue light (440-537nm) gives 8.3% increasement in lifespan. We demonstrate that the exposure to modulated light alleviates photo-oxidative stress and unfolded-protein response. We realize reflective passive cooling temperature using PCs, and favorable low temperature could be created for worms to extend lifespan. This work offers a new path based on PCs to resist negative effects light and temperature for longevity, provides an available platform for studying the role of light in aging.

Cold temperature extends longevity and prevents disease-related protein aggregation through PA28γ-induced proteasomes

Aging is a primary risk factor for neurodegenerative disorders that involve protein aggregation. Because lowering body temperature is one of the most effective mechanisms to extend longevity in both poikilotherms and homeotherms, a better understanding of cold-induced changes can lead to converging modifiers of pathological protein aggregation. Here, we find that cold temperature (15 °C) selectively induces the trypsin-like activity of the proteasome in Caenorhabditis elegans through PSME-3, the worm orthologue of human PA28γ/PSME3. This proteasome activator is required for cold-induced longevity and ameliorates age-related deficits in protein degradation. Moreover, cold-induced PA28γ/PSME-3 diminishes protein aggregation in C. elegans models of age-related diseases such as Huntington's and amyotrophic lateral sclerosis. Notably, exposure of human cells to moderate cold temperature (36 °C) also activates trypsin-like activity through PA28γ/PSME3, reducing disease-related protein aggregation and neurodegeneration. Together, our findings reveal a beneficial role of cold temperature that crosses evolutionary boundaries with potential implications for multi-disease prevention.

Methods to extract and study the biological effects of murine gut microbiota using Caenorhabditis elegans as a screening host

Gut microbiota has been established as a main regulator of health. However, how changes in gut microbiota are directly associated with physiological and cellular alterations has been difficult to tackle on a large-scale basis, notably because of the cost and labor-extensive resources required for rigorous experiments in mammals. In the present study, we used the nematode Caenorhabditis elegans as a model organism to elucidate microbiota-host interactions. We developed a method to extract gut microbiota (MCB) from murine feces, and tested its potential as food source for and its impact on C. elegans biology compared to the standard bacterial diet Escherichia coli OP50. Although less preferred than OP50, MCB was not avoided but had a lower energy density (triglycerides and glucose). Consistently, MCB-fed worms exhibited smaller body length and size, lower fertility, and lower fat content than OP50-fed worms, but had a longer mean lifespan, which resembles the effects of calorie restriction in mammals. However, these outcomes were altered when bacteria were inactivated, suggesting an important role of symbiosis of MCB beyond nutrient source. Taken together, our findings support the effectiveness of gut MCB processing to test its effects in C. elegans. More work comparing MCB of differently treated mice or humans is required to further validate relevance to mammals before large-scale screening assays.

Using Vital Signs to Place Acutely Ill Patients Quickly and Easily into Clinically Helpful Pathophysiologic Categories: Derivation and Validation of Eight Pathophysiologic Categories in Two Distinct Patient Populations of Acutely Ill Patients

BACKGROUND

Early warning scores reliably identify patients at risk of imminent death, but do not provide insight into what may be wrong with the patient or what to do about it.

OBJECTIVE

Our aim was to explore whether the Shock Index (SI), pulse pressure (PP), and ROX Index can place acutely ill medical patients in pathophysiologic categories that could indicate the interventions required.

METHODS

A retrospective post-hoc analysis of previously obtained and reported clinical data for 45,784 acutely ill medical patients admitted to a major regional referral Canadian hospital between 2005 and 2010 and validated on 107,546 emergency admissions to four Dutch hospitals between 2017 and 2022.

RESULTS

SI, PP, and ROX values divided patients into eight mutually exclusive physiologic categories. Mortality was highest in patient categories that included ROX Index value < 22, and a ROX Index value < 22 multiplied the risk of any other abnormality. Patients with a ROX Index value < 22, PP < 42 mm Hg, and SI > 0.7 had the highest mortality and accounted for 40% of deaths within 24 h of admission, whereas patients with a PP ≥ 42 mm Hg, SI ≤ 0.7, and ROX Index value ≥ 22 had the lowest risk of death. These results were the same in both the Canadian and Dutch patient cohorts.

CONCLUSIONS

SI, PP, and ROX Index values can place acutely ill medical patients into eight mutually exclusive pathophysiologic categories with different mortality rates. Future studies will assess the interventions needed by these categories and their value in guiding treatment and disposition decisions.

The innate immune signaling component FBXC-58 mediates dietary restriction effects on healthy aging in Caenorhabditis elegans

Dietary restriction (DR) is a highly effective and reproducible intervention that prolongs longevity in many organisms. The molecular mechanism of action of DR is tightly connected with the immune system; however, the detailed mechanisms and effective downstream factors of immunity that mediate the beneficial effects of DR on aging remain unknown. Here, to investigate the immune signaling that mediates DR effects, we used Caenorhabditis elegans, which has been widely used in research, to understand the underlying molecular mechanisms of aging and immunity. We found that the F-box gene, fbxc-58, a regulator of the innate immune response, is a novel mediator of DR effects on extending the health span of C. elegans. fbxc-58 is upregulated by DR and is necessary for DR-induced lifespan extension and physical health improvement in C. elegans. Furthermore, through DR, fbxc-58 prevents disintegration of the mitochondrial network in body wall muscle during aging. We found that fbxc-58 is a downstream target of the ZIP-2 and PHA-4 transcription factors, the well-known DR mediator, and fbxc-58 extends longevity in DR through an S6 kinase-dependent pathway. We propose that the novel DR effector, fbxc-58, could provide a new mechanistic understanding of the effects of DR on healthy aging and elucidate the signaling mechanisms that link immunity and DR effects with aging.

Eucommia ulmoides male flower as a remarkable edible floral resource exerts lifespan/healthspan-promoting effects on Caenorhabditis elegans

Natural products, especially phytochemicals, can effectively improve the health of various model organisms and ultimately prolong their lifespan. As an emerging resource of plant-based food, edible flowers have potential anti-aging effects. Here, we showed that twelve out of 30 drug-food homologous flowers' extracts significantly extended the lifespan of C. elegans, and the Eucommia ulmoides male flower was screened out by comparing centrally. The lifespan of C. elegans increased by 18.61% under the treatment of 100 μg mL^-1 floral extract (EUFE). Interestingly, this effect was attenuated when EUFE was administered late or at higher concentrations. Significantly, EUFE improved health indicators that decline with aging including pharyngeal pumping, mobility, muscle morphology, and lipofuscin accumulation. EUFE also enhanced the resistance of C. elegans to oxidative/heat stress. The longevity-extending effect of EUFE was dependent on transcription factor DAF-16 and mitochondrial function. Moreover, EUFE triggered the nuclear translocation of DAF-16 and promoted downstream LGG-1 and SOD3 protein expression. In body-wall muscles, EUFE stimulated mitochondrial fission and mitophagy to mitigate age-related mitochondrial impairments. The transcriptional checkpoints of daf-16, drp-1, eat-3, lgg-1, and dct-1 further showed that EUFE regulated DAF-16 signaling and mitochondrial homeostasis. Finally, the interpretation of the EUFE components by correlation analysis, UHPLC-QE-MS, and verification experiments showed that aucubin, geniposide, and asperuloside are the main active compounds. We revealed the excellent lifespan/healthspan-promoting efficacy of EUFE and highlighted that edible flowers are worthy of further investigation as anti-aging dietary resources. Meanwhile, related mechanisms enriched the hypothesis that mitochondria might be involved in the healthspan modulation of longevity pathways.

Analysis of a C. elegans lifespan prediction method based on a bimodal neural network and uncertainty estimation

In recent decades, assays with the nematode Caenorhabditis elegans (C. elegans) have enabled great advances to be made in research on aging. However, performing these assays manually is a laborious task. To solve this problem, numerous C. elegans assay automation techniques are being developed to increase throughput and accuracy. In this paper, a method for predicting the lifespan of C. elegans nematodes using a bimodal neural network is proposed and analyzed. Specifically, the model uses the sequence of images and the count of live C. elegans up to the current day to predict the lifespan curve termination. This network has been trained using a simulator to avoid the labeling costs of training such a model. In addition, a method for estimating the uncertainty of the model predictions has been proposed. Using this uncertainty, a criterion has been analyzed to decide at what point the assay could be halted and the user could rely on the model's predictions. The method has been analyzed and validated using real experiments. The results show that uncertainty is reduced from the mean lifespan and that most of the predictions obtained do not present statistically significant differences with respect to the curves obtained manually.

Nuclear import receptors are recruited by FG-nucleoporins to rescue hallmarks of TDP-43 proteinopathy

BACKGROUND

Cytoplasmic mislocalization and aggregation of TAR DNA-binding protein-43 (TDP-43) is a hallmark of the amyotrophic lateral sclerosis and frontotemporal dementia (ALS/FTD) disease spectrum, causing both nuclear loss-of-function and cytoplasmic toxic gain-of-function phenotypes. While TDP-43 proteinopathy has been associated with defects in nucleocytoplasmic transport, this process is still poorly understood. Here we study the role of karyopherin-β1 (KPNB1) and other nuclear import receptors in regulating TDP-43 pathology.

METHODS

We used immunostaining, immunoprecipitation, biochemical and toxicity assays in cell lines, primary neuron and organotypic mouse brain slice cultures, to determine the impact of KPNB1 on the solubility, localization, and toxicity of pathological TDP-43 constructs. Postmortem patient brain and spinal cord tissue was stained to assess KPNB1 colocalization with TDP-43 inclusions. Turbidity assays were employed to study the dissolution and prevention of aggregation of recombinant TDP-43 fibrils in vitro. Fly models of TDP-43 proteinopathy were used to determine the effect of KPNB1 on their neurodegenerative phenotype in vivo.

RESULTS

We discovered that several members of the nuclear import receptor protein family can reduce the formation of pathological TDP-43 aggregates. Using KPNB1 as a model, we found that its activity depends on the prion-like C-terminal region of TDP-43, which mediates the co-aggregation with phenylalanine and glycine-rich nucleoporins (FG-Nups) such as Nup62. KPNB1 is recruited into these co-aggregates where it acts as a molecular chaperone that reverses aberrant phase transition of Nup62 and TDP-43. These findings are supported by the discovery that Nup62 and KPNB1 are also sequestered into pathological TDP-43 aggregates in ALS/FTD postmortem CNS tissue, and by the identification of the fly ortholog of KPNB1 as a strong protective modifier in Drosophila models of TDP-43 proteinopathy. Our results show that KPNB1 can rescue all hallmarks of TDP-43 pathology, by restoring its solubility and nuclear localization, and reducing neurodegeneration in cellular and animal models of ALS/FTD.

CONCLUSION

Our findings suggest a novel NLS-independent mechanism where, analogous to its canonical role in dissolving the diffusion barrier formed by FG-Nups in the nuclear pore, KPNB1 is recruited into TDP-43/FG-Nup co-aggregates present in TDP-43 proteinopathies and therapeutically reverses their deleterious phase transition and mislocalization, mitigating neurodegeneration.

Sex‐based differences in early and late uveal melanoma‐related mortality

BACKGROUND

It is debated if there are sex-based differences in survival for patients with uveal melanoma. Previous observations of higher mortality for men in studies with <10-year follow-up have not been replicated in studies with longer follow-up. It is therefore hypothesized that women have a worse survival in later periods.

METHODS

All patients diagnosed with primary uveal melanoma in Sweden between 1980 and 2017 were included (n = 2032). Survival differences between men and women in early (<10 years from diagnosis) and late (≥10 years) periods were analyzed.

RESULTS

At baseline, there were no significant differences in mean patient age, tumor thickness, diameter, ciliary body involvement, primary treatment modality, or in American Joint Committee on Cancer (AJCC) T-category between men and women. In total, 764 patients (425 women and 339 men) survived and were followed ≥10 years. In this group, men were significantly younger, but there were no differences in baseline tumor thickness, diameter, ciliary body involvement, primary treatment, or AJCC T-category. In competing risk analysis, women had higher incidence of uveal melanoma-related mortality in the late period (p = 0.036). In univariate Cox regression, male (HR 1.2, p = 0.049) and female sex (HR 1.8, p = 0.034) were significant predictors of uveal melanoma-related mortality in the early and late periods, respectively.

CONCLUSION

Women with uveal melanoma have better survival in the first decade after diagnosis. Thereafter, female survivors are significantly older than men and have a higher incidence of uveal melanoma-related mortality.

BAM15 Relieves Neurodegeneration in Aged Caenorhabditis elegans and Extends Lifespan

BAM15 was recently screened as a protonophore uncoupler specifically for the mitochondrial membrane but not the plasma membrane. It is equally as potent as FCCP, but less toxic. Previously, mitochondrial uncoupling via DNP alleviates neurodegeneration in the nematode Caenorhabditis elegans during aging. Therefore, we investigated whether BAM15 uncouplers could phenotypically and functionally reduce neuronal defects in aged nematodes. We observed green fluorescence protein-tagged mechanosensory neurons and performed touch and chemotaxis assays during aging. Wild-type animals treated with both 50 µM BAM15 and 10 µM DNP showed reduced mechanosensory neuronal defects during aging, which correlates with the maintenance of touch responses and short-term memory during aging. Uncoupler mutant ucp-4 also responded the same way as the wild-type, reducing neurodegeneration in 50 µM BAM15 and 10 µM DNP-treated animals compared to the DMSO control. These results suggest that 50 µM BAM15 alleviates neurodegeneration phenotypically and functionally in C. elegans during aging, potentially through mitochondrial uncoupling. In accordance with the preserved neuronal shape and function in aged C. elegans, 50 µM BAM15 extended the mean lifespan of both wild-type and ucp-4 mutants.

Anti-Aging and Neuroprotective Properties of Grifola frondosa and Hericium erinaceus Extracts

Nutrition has relevant consequences for human health and increasing pieces of evidence indicate that medicinal mushrooms have several beneficial effects. One of the main issues in Western countries is represented by the challenges of aging and age-related diseases, such as neurodegenerative disorders. Among these, Parkinson’s disease (PD) affects 10 million people worldwide and is associated with α-synuclein misfolding, also found in other pathologies collectively called synucleinopathies. Here, we show that aqueous extracts of two edible mushrooms, Grifola frondosa and Hericium erinaceus, represent a valuable source of β-glucans and exert anti-aging effects in yeast. Their beneficial effects are mediated through the inhibition of the Ras/PKA pathway, with increased expression of heat shock proteins, along with a consistent increase of both mean and maximal lifespans. These fungal extracts also reduce the toxicity of α-synuclein heterologously expressed in yeast cells, resulting in reduced ROS levels, lower α-synuclein membrane localization, and protein aggregation. The neuroprotective activity of G. frondosa extract was also confirmed in a PD model of Drosophila melanogaster. Taken together, our data suggest the use of G. frondosa and H. erinaceus as functional food to prevent aging and age-related disorders, further supporting the neuro-healthy properties of these medicinal mushroom extracts.

Axenic Culture of Caenorhabditis elegans Alters Lysosomal/Proteasomal Balance and Increases Neuropeptide Expression

Axenically cultured C. elegans show many characteristic traits of worms subjected to dietary restriction, such as slowed development, reduced fertility, and increased stress resistance. Hence, the term axenic dietary restriction (ADR) is often applied. ADR dramatically extends the worm lifespan compared to other DR regimens such as bacterial dilution. However, the underlying molecular mechanisms still remain unclear. The primary goal of this study is to comprehensively investigate transcriptional alterations that occur when worms are subjected to ADR and to estimate the molecular and physiological changes that may underlie ADR-induced longevity. One of the most enriched clusters of up-regulated genes under ADR conditions is linked to lysosomal activity, while proteasomal genes are significantly down-regulated. The up-regulation of genes specifically involved in amino acid metabolism is likely a response to the high peptide levels found in axenic culture medium. Genes related to the integrity and function of muscles and the extracellular matrix are also up-regulated. Consistent down-regulation of genes involved in DNA replication and repair may reflect the reduced fertility phenotype of ADR worms. Neuropeptide genes are found to be largely up-regulated, suggesting a possible involvement of neuroendocrinal signaling in ADR-induced longevity. In conclusion, axenically cultured worms seem to rely on increased amino acid catabolism, relocate protein breakdown from the cytosol to the lysosomes, and do not invest in DNA maintenance but rather retain muscle integrity and the extracellular matrix. All these changes may be coordinated by peptidergic signaling.

Drosophila as a Model Organism to Study Basic Mechanisms of Longevity

The spatio-temporal regulation of gene expression determines the fate and function of various cells and tissues and, as a consequence, the correct development and functioning of complex organisms. Certain mechanisms of gene activity regulation provide adequate cell responses to changes in environmental factors. Aside from gene expression disorders that lead to various pathologies, alterations of expression of particular genes were shown to significantly decrease or increase the lifespan in a wide range of organisms from yeast to human. Drosophila fruit fly is an ideal model system to explore mechanisms of longevity and aging due to low cost, easy handling and maintenance, large number of progeny per adult, short life cycle and lifespan, relatively low number of paralogous genes, high evolutionary conservation of epigenetic mechanisms and signalling pathways, and availability of a wide range of tools to modulate gene expression in vivo. Here, we focus on the organization of the evolutionarily conserved signaling pathways whose components significantly influence the aging process and on the interconnections of these pathways with gene expression regulation.

Effect of DMSO on lifespan and physiology in C. elegans : Implications for use of DMSO as a solvent for compound delivery

Dimethyl sulfoxide (DMSO) is a solvent that has been used for basic and medical research based on its ability to dissolve both polar and non-polar compounds. In order to use DMSO to deliver compounds that may impact longevity or neurodegeneration, it is important to first determine the effects of DMSO on aging and physiology. We examined the effect of different concentrations of DMSO on lifespan and development time in C. elegans. We found that DMSO concentrations up to 2% DMSO did not affect longevity in wild-type worms, while concentrations of up to 0.5% DMSO were compatible with normal development times. 0.5% DMSO also had minimal effect on fertility and movement. In summary, our results show that concentrations of DMSO up to 0.5% can be safely used to deliver compounds to C. elegans with little or no modifying effects on lifespan or physiologic rates.

Citric Acid-Derived Carbon Quantum Dots Attenuate Paraquat-Induced Neuronal Compromise In Vitro and In Vivo

The potent environmental herbicide and weedicide paraquat is linked to neuromotor defects and Parkinson's disease (PD). We have evaluated the neuroprotective role of citric acid-sourced carbon quantum dots (Cit-CQDs) on paraquat-insulted human neuroblastoma-derived SH-SY5Y cell lines and on a paraquat-exposed nematode (Caenorhabditis elegans). Our data reveal that Cit-CQDs are able to scavenge free radicals in test tube assays and mitigate paraquat-elevated reactive oxygen species (ROS) levels in SH-SY5Y cells. Furthermore, Cit-CQDs protect the cell line from paraquat, which otherwise elicits cell death. Cit-CQDs-challenged nematodes demonstrate enhanced survival rates 72 h post-paraquat exposure compared to controls. Paraquat ablates dopamine (DA) neurons, which results in compromised locomotor function in nematodes. However, the neurons remained intact when the nematodes were incubated with Cit-CQDs prior to neurotoxicant exposure. The collective data suggest Cit-CQDs offer neuroprotection for cell lines and organisms from xenotoxicant-associated neuronal injury and death. The study suggests Cit-CQDs as a potentially viable green chemistry-synthesized, biobased nanomaterial for intervention in neurodegenerative disorders.

Sexual dimorphism in Caenorhabditis elegans stress resistance

Physiological responses to the environment, disease, and aging vary by sex in many animals, but mechanisms of dimorphism have only recently begun to receive careful attention. The genetic model nematode Caenorhabditis elegans has well-defined mechanisms of stress response, aging, and sexual differentiation. C. elegans has males, but the vast majority of research only uses hermaphrodites. We found that males of the standard N2 laboratory strain were more resistant to hyperosmolarity, heat, and a natural pro-oxidant than hermaphrodites when in mixed-sex groups. Resistance to heat and pro-oxidant were also male-biased in three genetically and geographically diverse C. elegans strains consistent with a species-wide dimorphism that is not specific to domestication. N2 males were also more resistant to heat and pro-oxidant when keep individually indicating that differences in resistance do not require interactions between worms. We found that males induce canonical stress response genes by similar degrees and in similar tissues as hermaphrodites suggesting the importance of other mechanisms. We find that resistance to heat and pro-oxidant are influenced by the sex differentiation transcription factor TRA-1 suggesting that downstream organ differentiation pathways establish differences in stress resistance. Environmental stress influences survival in natural environments, degenerative disease, and aging. Understanding mechanisms of stress response dimorphism can therefore provide insights into sex-specific population dynamics, disease, and longevity.

Microbiome Analysis of Malacopathogenic Nematodes Suggests No Evidence of a Single Bacterial Symbiont Responsible for Gastropod Mortality

Nematodes and bacteria are prevalent in soil ecosystems, and some have evolved symbiotic relationships. In some cases, symbionts carry out highly specialized functions: a prime example being entomopathogenic nematodes (EPNs), which vector bacteria (Xenorhabdus or Photorhabdus) into insect hosts, killing them to provide a food source for the nematodes. It is thought that the commercially available malacopathogenic (kills slugs and snails) biocontrol nematode Phasmarhabditis hermaphrodita vectors a bacterium (Moraxella osloensis) into slugs to kill them. To investigate this further we used a metagenomic approach to profile the bacteria present in the commercial strain of P. hermaphrodita, a wild strain of P. hermaphrodita and two other Phasmarhabditis species (P. californica and P. neopapillosa), after they had killed their slug host (Deroceras invadens). We show that these nematodes do not exclusively associate with one bacterium but a range of species, with members of the phyla Pseudomonadota, Bacillota, Actinobacteriota and Bacteroidota the most prevalent. The commercial strain of P. hermaphrodita had the least diverse bacterial community. Furthermore, we found that the bacterium P. hermaphrodita has been cultured on for 25 years is not the expected species M. osloensis but is Psychrobacter spp. and the only strain of the Phasmarhabditis species to associate with Psychrobacter spp. was the commercial strain of P. hermaphrodita. In summary, we found no evidence to show that P. hermaphrodita rely exclusively on one bacterium to cause host mortality but found variable and diverse bacterial communities associated with these nematodes in their slug hosts.

Can the ECG be used to estimate age-related survival?

BACKGROUND

There are few reports of the relationship between electrocardiogram (ECG) findings and the age-related survival of acutely ill patients.

AIM

This study compared the 1-year survival curves of patients attending two Danish emergency departments (EDs) with normal and abnormal ECGs. Patients were divided into age groups from 20 to 90 years of age, and an abnormal ECG was defined as low QRS voltage (i.e. lead I + II <1.4 mV) or QTc interval prolongation >434 ms.

METHODS

A retrospective register-based observational study on 35 496 patients attending two Danish EDs, with 100% follow-up for 1 year.

RESULTS

ECG abnormality increases linearly with age, and between 30 and 70 years of age. Patients aged 20-29 years with ECG abnormalities are more than four times more likely to die within a year than patients of the same age with a normal ECG. An individual with an abnormal ECG has the same risk of dying within a year as an individual with a normal ECG who is 10 years older. After 70 years of age this tight relationship ends, but for younger individuals with an abnormal ECG the increase in mortality is even higher.

CONCLUSION

An ECG may be a simple practical estimate of age-related survival. For a patient under 70 years, an abnormal QRS voltage or a prolonged QTc interval may increase 1-year mortality to that of a patient ∼10 years older.

Aryl Hydrocarbon Receptor-Dependent and -Independent Pathways Mediate Curcumin Anti-Aging Effects

The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor whose activity can be modulated by polyphenols, such as curcumin. AhR and curcumin have evolutionarily conserved effects on aging. Here, we investigated whether and how the AhR mediates the anti-aging effects of curcumin across species. Using a combination of in vivo, in vitro, and in silico analyses, we demonstrated that curcumin has AhR-dependent or -independent effects in a context-specific manner. We found that in Caenorhabditis elegans, AhR mediates curcumin-induced lifespan extension, most likely through a ligand-independent inhibitory mechanism related to its antioxidant activity. Curcumin also showed AhR-independent anti-aging activities, such as protection against aggregation-prone proteins and oxidative stress in C. elegans and promotion of the migratory capacity of human primary endothelial cells. These AhR-independent effects are largely mediated by the Nrf2/SKN-1 pathway.

Pterostilbene Promotes Mean Lifespan in Both Male and Female Drosophila Melanogaster Modulating Different Proteins in the Two Sexes

Aging is a multifactorial phenomenon characterized by degenerative processes closely connected to oxidative damage and chronic inflammation. Recently, many studies have shown that natural bioactive compounds are useful in delaying the aging process. In this work, we studied the effects of an in vivo supplementation of the stilbenoid pterostilbene on lifespan extension in Drosophila melanogaster. We found that the average lifespan of flies of both sexes was increased by pterostilbene supplementation with a higher effect in females. The expression of longevity related genes (Sir2, Foxo, and Notch) was increased in both sexes but with different patterns. Pterostilbene counteracted oxidative stress induced by ethanol and paraquat and up-regulated the antioxidant enzymes Ho e Trxr-1 in male but not in female flies. On the other hand, pterostilbene decreased the inflammatory mediators dome and egr only in female flies. Proteomic analysis revealed that pterostilbene modulates 113 proteins in male flies and only 9 in females. Only one of these proteins was modulated by pterostilbene in both sexes: vacuolar H[+] ATPase 68 kDa subunit 2 (Vha68-2) that was strongly down-regulated. These findings suggest a potential role of pterostilbene in increasing lifespan both in male and female flies by mechanisms that seem to be different in the two sexes, highlighting the need to conduct nutraceutical supplementation studies on males and females separately in order to give more reliable results.

A Potential Probiotic Lactobacillus plantarum JBC5 Improves Longevity and Healthy Aging by Modulating Antioxidative, Innate Immunity and Serotonin-Signaling Pathways in Caenorhabditis elegans

Since the hypothesis of Dr. Elie Metchnikoff on lactobacilli-mediated healthy aging, several microbes have been reported to extend the lifespan with different features of healthy aging. However, a microbe affecting diverse features of healthy aging is of choice for broader acceptance and marketability as a next-generation probiotic. We employed Caenorhabditis elegans as a model to understand the potential of Lactobacillus plantarum JBC5 (LPJBC5), isolated from fermented food sample on longevity and healthy aging as well as their underlying mechanisms. Firstly, LPJBC5 enhanced the mean lifespan of C. elegans by 27.81% compared with control (untreated). LPBC5-induced longevity was accompanied with better aging-associated biomarkers, such as physical functions, fat, and lipofuscin accumulation. Lifespan assay on mutant worms and gene expression studies indicated that LPJBC5-mediated longevity was due to upregulation of the skinhead-1 (skn-1) gene activated through p38 MAPK signaling cascade. Secondly, the activated transcription factor SKN-1 upregulated the expression of antioxidative, thermo-tolerant, and anti-pathogenic genes. In support, LPJBC5 conferred resistance against abiotic and biotic stresses such as oxidative, heat, and pathogen. LPJBC5 upregulated the expression of intestinal tight junction protein ZOO-1 and improved gut integrity. Thirdly, LPJBC5 improved the learning and memory of worms trained on LPJBC5 compared with naive worms. The results showed upregulation of genes involved in serotonin signaling (ser-1, mod-1, and tph-1) in LPJBC5-fed worms compared with control, suggesting that serotonin-signaling was essential for LPJBC5-mediated improved cognitive function. Fourthly, LPJBC5 decreased the fat accumulation in worms by reducing the expression of genes encoding key substrates and enzymes of fat metabolism (i.e., fat-5 and fat-7). Lastly, LPJBC5 reduced the production of reactive oxygen species and improved mitochondrial function, thereby reducing apoptosis in worms. The capability of a single bacterium on pro-longevity and the features of healthy aging, including enhancement of gut integrity and cognitive functions, makes it an ideal candidate for promotion as a next-generation probiotic.

UNC-33L partially rescues life span and locomotion defects in unc-33 mutants but fails to rescue dauer formation defects

Herein, we tested the ability of UNC-33L to rescue dauer formation, lifespan, and locomotion defects of unc-33(mn407) mutants. Results show that the presence of UNC-33L does not rescue the defective dauer phenotype in unc-33(mn407) mutants. However, UNC-33L significantly rescued premature death and uncoordinated locomotion in young unc-33(mn407) adults. The degree of UNC-33L-mediated rescue was less noticeable as the nematodes aged, denoting that both age and the presence of UNC-33L interact in the production of the phenotypes.

An extract of Rosaceae, Solanaceae and Zingiberaceae increases health span and mobility in Caenorhabditis elegans

Background

Members of the Rosaceae, Solanaceae and Zingiberaceae families which include fruits such as cherries, tomatoes and ginger are known to have health promoting effects. There is growing interest in consuming these “functional foods” as a means to increase health and healthy ageing. However, many studies explore the effect of these foods in isolation, not as a blend of multiple functional foods.

Methods

In this study, an extract containing the dried berries, fruits, and roots of members of these families was prepared, which we called Bioact®180. The nematode Caenorhabditis elegans was used to evaluate the effects of Bioact®180 on lifespan and health endpoints, including muscle and mitochondria structure and locomotion.

Results

Exposure to the 1000 µg/mL of Bioact®180 extract, containing 4% total phenols, were healthier, as observed by an increase in mean lifespan with and small but significant increase in maximal lifespan. Nematodes exposed to Bioact®180 displayed better mobility in mid-life stages as well as enhanced mitochondrial morphology, which was more comparable to younger animals, suggesting that these worms are protected to some degree from sarcopenia.

Conclusions

Together, our findings reveal that Bioact®180, a blend of fruits and roots from Rosaceae, Solanaceae and Zingiberaceae family members has anti-aging effects. Bioact®180 promotes health and lifespan extension in C. elegans, corresponding to functional improvements in mobility.

Evaluation of lifespan promoting effects of biofortified wheat in Drosophila melanogaster

Evaluation of nutritionally enhanced biofortified dietary interventions that increase lifespan may uncover cost-effective and sustainable approaches for treatment of age-related morbidities and increasing healthy life expectancy. In this study, we report that anthocyanin rich, high yielding crossbred blue wheat prolongs lifespan of Drosophila melanogaster in different dietary contexts. In addition to functioning as an antioxidant rich intervention, the biofortified blue wheat also works through modulating expression of DR pathway genes including AMPK alpha, SREBP, PEPCK and Cry. Supplementation with blue- or purple-colored wheat provided better protection against paraquat-induced oxidative stress than control diet and increased survivability of flies in which superoxide dismutase 2 was knocked down conditionally in adults. Lastly, our findings indicate that supplementing biofortified blue wheat formulated diet prevented the decrease in lifespan and cardiac structural pathologies associated with intake of high fat diet. Overall, our findings indicate that plant-based diets formulated with biofortified cereal crops promote healthy ageing and delay progression of diseases that are exacerbated by accumulation of oxidative damage.

Mutations in trpγ, the homologue of TRPC6 autism candidate gene, causes autism-like behavioral deficits in Drosophila

Autism Spectrum Disorder (ASD) is characterized by impaired social communication, restricted interests, and repetitive and stereotyped behaviors. The TRPC6 (transient receptor potential channel 6) represents an ASD candidate gene under an oligogenic/multifactorial model based on the initial description and cellular characterization of an individual with ASD bearing a de novo heterozygous mutation disrupting TRPC6, together with the enrichment of disruptive TRPC6 variants in ASD cases as compared to controls. Here, we perform a clinical re-evaluation of the initial non-verbal patient, and also present eight newly reported individuals ascertained for ASD and bearing predicted loss-of-function mutations in TRPC6. In order to understand the consequences of mutations in TRPC6 on nervous system function, we used the fruit fly, Drosophila melanogaster, to show that null mutations in transient receptor gamma (trpγ; the fly gene most similar to TRPC6), cause a number of behavioral defects that mirror features seen in ASD patients, including deficits in social interactions (based on courtship behavior), impaired sleep homeostasis (without affecting the circadian control of sleep), hyperactivity in both young and old flies, and defects in learning and memory. Some defects, most notably in sleep, differed in severity between males and females and became normal with age. Interestingly, hyperforin, a TRPC6 agonist and the primary active component of the St. John's wort antidepressant, attenuated many of the deficits expressed by trpγ mutant flies. In summary, our results provide further evidence that the TRPC6 gene is a risk factor for ASD. In addition, they show that the behavioral defects caused by mutations in TRPC6 can be modeled in Drosophila, thereby establishing a paradigm to examine the impact of mutations in other candidate genes.

Loss of SET1/COMPASS methyltransferase activity reduces lifespan and fertility in Caenorhabditis elegans

Changes in histone post-translational modifications are associated with aging through poorly defined mechanisms. Histone 3 lysine 4 (H3K4) methylation at promoters is deposited by SET1 family methyltransferases acting within conserved multiprotein complexes known as COMPASS. Previous work yielded conflicting results about the requirement for H3K4 methylation during aging. Here, we reassessed the role of SET1/COMPASS-dependent H3K4 methylation in Caenorhabditis elegans lifespan and fertility by generating set-2(syb2085) mutant animals that express a catalytically inactive form of SET-2, the C. elegans SET1 homolog. We show that set-2(syb2085) animals retain the ability to form COMPASS, but have a marked global loss of H3K4 di- and trimethylation (H3K4me2/3). Reduced H3K4 methylation was accompanied by loss of fertility, as expected; however, in contrast to earlier studies, set-2(syb2085) mutants displayed a significantly shortened, not extended, lifespan and had normal intestinal fat stores. Other commonly used set-2 mutants were also short-lived, as was a cfp-1 mutant that lacks the SET1/COMPASS chromatin-targeting component. These results challenge previously held views and establish that WT H3K4me2/3 levels are essential for normal lifespan in C. elegans.

MON-2, a Golgi protein, mediates autophagy-dependent longevity in Caenorhabditis elegans

The Golgi apparatus plays a central role in trafficking cargoes such as proteins and lipids. Defects in the Golgi apparatus lead to various diseases, but its role in organismal longevity is largely unknown. Using a quantitative proteomic approach, we found that a Golgi protein, MON-2, was up-regulated in long-lived Caenorhabditis elegans mutants with mitochondrial respiration defects and was required for their longevity. Similarly, we showed that DOP1/PAD-1, which acts with MON-2 to traffic macromolecules between the Golgi and endosome, contributed to the longevity of respiration mutants. Furthermore, we demonstrated that MON-2 was required for up-regulation of autophagy, a longevity-associated recycling process, by activating the Atg8 ortholog GABARAP/LGG-1 in C. elegans. Consistently, we showed that mammalian MON2 activated GABARAPL2 through physical interaction, which increased autophagic flux in mammalian cells. Thus, the evolutionarily conserved role of MON2 in trafficking between the Golgi and endosome is an integral part of autophagy-mediated longevity.

The nuclear ubiquitin ligase adaptor SPOP is a conserved regulator of C9orf72 dipeptide toxicity

A hexanucleotide repeat expansion in the C9orf72 gene is the most common cause of inherited amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Unconventional translation of the C9orf72 repeat produces dipeptide repeat proteins (DPRs). Previously, we showed that the DPRs PR50 and GR50 are highly toxic when expressed in Caenorhabditis elegans, and this toxicity depends on nuclear localization of the DPR. In an unbiased genome-wide RNA interference (RNAi) screen for suppressors of PR50 toxicity, we identified 12 genes that consistently suppressed either the developmental arrest and/or paralysis phenotype evoked by PR50 expression. All of these genes have vertebrate homologs, and 7 of 12 contain predicted nuclear localization signals. One of these genes was spop-1, the C. elegans homolog of SPOP, a nuclear localized E3 ubiquitin ligase adaptor only found in metazoans. SPOP is also required for GR50 toxicity and functions in a genetic pathway that includes cul-3, which is the canonical E3 ligase partner for SPOP Genetic or pharmacological inhibition of SPOP in mammalian primary spinal cord motor neurons suppressed DPR toxicity without affecting DPR expression levels. Finally, we find that knockdown of bromodomain proteins in both C. elegans and mammalian neurons, which are known SPOP ubiquitination targets, suppresses the protective effect of SPOP inhibition. Together, these data suggest a model in which SPOP promotes the DPR-dependent ubiquitination and degradation of BRD proteins. We speculate the pharmacological manipulation of this pathway, which is currently underway for multiple cancer subtypes, could also represent an entry point for therapeutic intervention to treat C9orf72 FTD/ALS.

A PTEN variant uncouples longevity from impaired fitness in Caenorhabditis elegans with reduced insulin/IGF-1 signaling

Insulin/IGF-1 signaling (IIS) regulates various physiological aspects in numerous species. In Caenorhabditis elegans, mutations in the daf-2/insulin/IGF-1 receptor dramatically increase lifespan and immunity, but generally impair motility, growth, and reproduction. Whether these pleiotropic effects can be dissociated at a specific step in insulin/IGF-1 signaling pathway remains unknown. Through performing a mutagenesis screen, we identified a missense mutation daf-18(yh1) that alters a cysteine to tyrosine in DAF-18/PTEN phosphatase, which maintained the long lifespan and enhanced immunity, while improving the reduced motility in adult daf-2 mutants. We showed that the daf-18(yh1) mutation decreased the lipid phosphatase activity of DAF-18/PTEN, while retaining a partial protein tyrosine phosphatase activity. We found that daf-18(yh1) maintained the partial activity of DAF-16/FOXO but restricted the detrimental upregulation of SKN-1/NRF2, contributing to beneficial physiological traits in daf-2 mutants. Our work provides important insights into how one evolutionarily conserved component, PTEN, can coordinate animal health and longevity.

Rewiring of the ubiquitinated proteome determines ageing in C. elegans

Ageing is driven by a loss of cellular integrity1. Given the major role of ubiquitin modifications in cell function2, here we assess the link between ubiquitination and ageing by quantifying whole-proteome ubiquitin signatures in Caenorhabditis elegans. We find a remodelling of the ubiquitinated proteome during ageing, which is ameliorated by longevity paradigms such as dietary restriction and reduced insulin signalling. Notably, ageing causes a global loss of ubiquitination that is triggered by increased deubiquitinase activity. Because ubiquitination can tag proteins for recognition by the proteasome3, a fundamental question is whether deficits in targeted degradation influence longevity. By integrating data from worms with a defective proteasome, we identify proteasomal targets that accumulate with age owing to decreased ubiquitination and subsequent degradation. Lowering the levels of age-dysregulated proteasome targets prolongs longevity, whereas preventing their degradation shortens lifespan. Among the proteasomal targets, we find the IFB-2 intermediate filament4 and the EPS-8 modulator of RAC signalling5. While increased levels of IFB-2 promote the loss of intestinal integrity and bacterial colonization, upregulation of EPS-8 hyperactivates RAC in muscle and neurons, and leads to alterations in the actin cytoskeleton and protein kinase JNK. In summary, age-related changes in targeted degradation of structural and regulatory proteins across tissues determine longevity.

Towards Lifespan Automation for Caenorhabditis elegans Based on Deep Learning: Analysing Convolutional and Recurrent Neural Networks for Dead or Live Classification

The automation of lifespan assays with C. elegans in standard Petri dishes is a challenging problem because there are several problems hindering detection such as occlusions at the plate edges, dirt accumulation, and worm aggregations. Moreover, determining whether a worm is alive or dead can be complex as they barely move during the last few days of their lives. This paper proposes a method combining traditional computer vision techniques with a live/dead C. elegans classifier based on convolutional and recurrent neural networks from low-resolution image sequences. In addition to proposing a new method to automate lifespan, the use of data augmentation techniques is proposed to train the network in the absence of large numbers of samples. The proposed method achieved small error rates (3.54% ± 1.30% per plate) with respect to the manual curve, demonstrating its feasibility.

Opportunistic gill infection is associated with TiO2 nanoparticle-induced mortality in zebrafish

The large amounts of engineered titanium dioxide nanoparticles (TiO2NPs) that have been manufactured have inevitably been released into the ecosystem. Reports have suggested that TiO2 is a relatively inert material that has low toxicity to animals. However, as various types of NPs increasingly accumulate in the ocean, their effects on aquatic life-forms remain unclear. In this study, a zebrafish model was used to investigate TiO2NP-induced injury and mortality. We found that the treatment dosages of TiO2NP are positively associated with increased motility of zebrafish and the bacterial counts in the water. Notably, gill but not dorsal fin and caudal fin of the zebrafish displayed considerably increased bacterial load. Metagenomic analysis further revealed that gut microflora, such as phyla Proteobacteria, Bacteroidetes, and Actinobacteria, involving more than 95% of total bacteria counts in the NP-injured zebrafish gill samples. These results collectively suggest that opportunistic bacterial infections are associated with TiO2NP-induced mortality in zebrafish. Infections secondary to TiO2NP-induced injury could be a neglected factor determining the detrimental effects of TiO2NPs on wild fish.

miR-125-chinmo pathway regulates dietary restriction-dependent enhancement of lifespan in Drosophila

Dietary restriction (DR) extends healthy lifespan in diverse species. Age and nutrient-related changes in the abundance of microRNAs (miRNAs) and their processing factors have been linked to organismal longevity. However, the mechanisms by which they modulate lifespan and the tissue-specific role of miRNA-mediated networks in DR-dependent enhancement of lifespan remains largely unexplored. We show that two neuronally enriched and highly conserved microRNAs, miR-125 and let-7 mediate the DR response in Drosophila melanogaster. Functional characterization of miR-125 demonstrates its role in neurons while its target chinmo acts both in neurons and the fat body to modulate fat metabolism and longevity. Proteomic analysis revealed that Chinmo exerts its DR effects by regulating the expression of FATP, CG2017, CG9577, CG17554, CG5009, CG8778, CG9527, and FASN1. Our findings identify miR-125 as a conserved effector of the DR pathway and open the avenue for this small RNA molecule and its downstream effectors to be considered as potential drug candidates for the treatment of late-onset diseases and biomarkers for healthy aging in humans.

Systemic regulation of mitochondria by germline proteostasis prevents protein aggregation in the soma of C. elegans

Protein aggregation causes intracellular changes in neurons, which elicit signals to modulate proteostasis in the periphery. Beyond the nervous system, a fundamental question is whether other organs also communicate their proteostasis status to distal tissues. Here, we examine whether proteostasis of the germ line influences somatic tissues. To this end, we induce aggregation of germline-specific PGL-1 protein in germline stem cells of Caenorhabditis elegans Besides altering the intracellular mitochondrial network of germline cells, PGL-1 aggregation also reduces the mitochondrial content of somatic tissues through long-range Wnt signaling pathway. This process induces the unfolded protein response of the mitochondria in the soma, promoting somatic mitochondrial fragmentation and aggregation of proteins linked with neurodegenerative diseases such as Huntington's and amyotrophic lateral sclerosis. Thus, the proteostasis status of germline stem cells coordinates mitochondrial networks and protein aggregation through the organism.

Intestine-to-Germline Transmission of Epigenetic Information Intergenerationally Ensures Systemic Stress Resistance in C. elegans

Changes in epigenetic states affect organismal homeostasis, including stress resistance. However, the mechanisms coordinating epigenetic states and systemic stress resistance remain largely unknown. Here, we identify the intestine-to-germline communication of epigenetic states, which intergenerationally enhances stress resistance in C. elegans. The alterations in epigenetic states by deficiency of the histone H3K4me3 modifier ASH-2 in the intestine or germline increase organismal stress resistance, which is abrogated by knockdown of the H3K4 demethylase RBR-2. Remarkably, the increase in stress resistance induced by ASH-2 deficiency in the intestine is abrogated by RBR-2 knockdown in the germline, suggesting the intestine-to-germline transmission of epigenetic information. This communication from intestine to germline in the parental generation increases stress resistance in the next generation. Moreover, the intertissue communication is mediated partly by transcriptional regulation of F08F1.3. These results reveal that intertissue communication of epigenetic information provides mechanisms for intergenerational regulation of systemic stress resistance.