Project description:Aging is a major international concern and brings with it formidable socioeconomical and healthcare challenges. An attainable approach to improve general health in humans is using small molecules. Tomatidine, a natural compound abundant in unripe tomatoes, inhibits aging-related skeletal muscle atrophy in mice. Here we show that tomatidine extends lifespan and healthspan in the aging animal model C. elegans, which shares many major longevity pathways with those of mammals. Tomatidine improves behaviors related to healthspan, including increased pharyngeal pumping and swimming movement, and also reduces deterioration of muscle cells in worms. Microarray, imaging, and behavioral analysis reveal that tomatidine maintains mitochondrial homeostasis through mitochondrial biogenesis and PINK-1/DCT-1-dependent mitophagy. Mechanistically, tomatidine induces mitochondrial hormesis by mildly inducing ROS production, which in turn activates the cellular antioxidant response SKN-1/Nrf2 pathway, followed by increased mitophagy in worms, primary rat neurons, and human cells. Our data suggest that tomatidine may delay some physiological aspects of aging, and points to new approaches for pharmacological interventions towards diseases of aging.
Project description:Mitochondrial damage and mitophagy deregulation are hallmark features of aging and age-related pathologies. Urolithin A (UA), a potent mitophagy inducer, is known to confer neuroprotection, maintain muscle integrity, and extend healthspan and lifespan across diverse species. However, the molecular mechanisms underlying UA-mediated mitophagy remain largely unknown. Here, we demonstrate that UA treatment modulates cytosolic calcium levels, which are essential for initiating robust mitophagy in both neurons and muscles. Transcriptomic and proteomic analyses reveal that UA facilitates the reorganization of interorganellar communication between the endoplasmic reticulum (ER), lysosomes, and mitochondria, a process that is highly dependent on calcium signaling. Our findings suggest that calcium is released from the ER, subsequently enhancing lysosomal activity and facilitating mitochondrial entry, ultimately leading to mitochondrial fission and the successful execution of mitophagy. Notably, calcium chelation abolishes UA-induced mitophagy, leading to impaired muscle function and diminished lifespan extension, underscoring the indispensable role of calcium dynamics.We further found that UA-induced calcium elevation triggers mitochondrial biogenesis through the activation of UNC-43/CaMKII and SKN-1/Nrf2, mechanisms critical for healthspan and lifespan extension. In human cells, UA supplementation not only induces mitophagy but also enhances mitochondrial metabolism and prevents stress-induced senescence in a calcium-dependent manner. Ultimately, our findings uncover the mechanistic insights of UA-mediated geroprotection and underscore the central role of calcium dynamics in orchestrating the crosstalk between different cellular compartments, thereby sustaining energy homeostasis and overall organismal physiology.
Project description:The role of ellagic acid (EA), a natural antioxidant, in regulating anti-aging and its underlying mechanisms remains unclear. In this study, we investigated the anti-aging effects and molecular mechanisms of EA in Caenorhabditis elegans (C. elegans). Our results demonstrate that EA extends the lifespan of C. elegans, enhances motility, reduces lipofuscin accumulation, and improves overall healthspan. Additionally, EA reduces reactive oxygen species (ROS) accumulation in C. elegans under conditions of heat and oxidative stress. The insulin/IGF-1 signaling (IIS) pathway, a key regulator of longevity and stress resistance in C. elegans, was found to mediate EA's effects. EA treatment did not extend the lifespan of mutants defective in daf-2, daf-16, hsf-1, hlh-30, and skn-1, confirming that EA’s lifespan-extending effect operates through the IIS pathway. Furthermore, EA treatment increased the expression of stress response genes downstream of the IIS pathway. Based on RNA sequencing data, we further explored the molecular mechanisms and potential regulatory roles of EA in anti-aging.
Project description:Reactive Oxygen Species increase gradually with aging and Steadily diminish the cell's ability to maintain homeostasis. Nuclear Factor-like 2 and its C elegans ortholog, SKN-1 are transcription factors that play a pivotal role in oxidative stress response, cellular homeostasis and lifespan. But like other defence systems, Nrf2-mediated stress response is compromised in aging and neurodegenerative diseases. In this study we provide evidence that this FDA-approved drug is a bona fide activator of Nrf2/SKN-1 pathway.
Project description:D-Glucosamine (2-amino-2-deoxy-D-glucose, C.A.S.# 3416-24-8) (GlcN) is a freely available and commonly used dietary supplement possibly promoting cartilage health in humans which also acts as an inhibitor of glycolysis. We here find that GlcN extends C. elegans lifespan by impairing glucose metabolism to activate AMP-activated protein kinase (AMPK/AAK2) leading to increased mitochondrial biogenesis. Consistent with the concept of mitohormesis, this promotes increased formation of mitochondrial reactive oxygen species (ROS) and p38/PMK-1-mediated stress signaling culminating in increased expression of the nematodal amino acid-transporter 1 (aat-1) gene. Ameliorating mitochondrial ROS formation as well as impairment of aat-1-expression abolishes GlcN-mediated lifespan extension in a NRF2/SKN-1-dependent fashion. Notably and unlike other calorie restriction mimetics (CRM) like 2-deoxy-D-glucose (2DG, DOG), GlcN extends lifespan of aging C57BL/6 mice (log-rank: p=0.002; cox regression: p=0.01) similarly paralleled by an induction of mitochondrial biogenesis, increased expression of several murine amino acid transporters, as well as increased amino-acid catabolism. Taken together, GlcN mimics a ketogenic diet to extend healthspan in evolutionary distinct species. 24 samples: 12 mRNA profiles of C.elegans: 6 without GlcN and 6 with GlcN supplementaion; 12 mRNA profiles of M.musculus: 6 without GlcN and 6 with GlcN supplementaion
Project description:Hormesis occurs when a low level stress elicits adaptive beneficial responses that protect against subsequent exposure to severe stress. Recent findings suggest that mild oxidative and thermal stress can extend lifespan by hormetic mechanisms. Here we show that the botanical pesticide plumbagin, while toxic to C. elegans nematodes at high doses, extends lifespan at low doses. Because plumbagin is a naphthoquinone that generates free radicals in vivo, we investigated whether it extends lifespan by activating an adaptive cellular stress response pathway. Mammalian NF-E2-related factor 2 (Nrf2) and its C. elegans ortholog SKN-1, mediate protective responses to oxidative stress by promoting target gene expression via antioxidant response elements (ARE). Genetic analyses showed that skn-1 mediates plumbagin’s lifespan-extending effect in C. elegans. Further screening of a series of plumbagin analogs identified three additional naphthoquinones that could induce SKN-1 targets in C. elegans. Naphthazarin showed skn-1-dependent lifespan extension, over an extended dose range compared to plumbagin, while the other naphthoquinones, oxoline and menadione, had differing effects on C. elegans survival and failed to activate ARE reporter expression in cultured mammalian cells. Our findings reveal the potential for low doses of naturally occurring naphthoquinones to extend lifespan by engaging a specific adaptive cellular stress response pathway.
Project description:The C. elegans lifespan in the presence of Bacillus licheniformis caused induction of a large number of genes associated with anti-aging activiy including beta-oxidation Inaddition, these results indicate the B. licheniformis enhances the lifespan of Caenorhabditis elegans through serotonin signaling
Project description:The C. elegans lifespan in the presence of Bacillus licheniformis caused induction of a large number of genes associated with anti-aging activiy including beta-oxidation Inaddition, these results indicate the B. licheniformis enhances the lifespan of Caenorhabditis elegans through serotonin signaling Two-condition experiment, C. elegans with B. lichemiformis 141 or E. coli OP50 (conrol) for 24 h. For preparing the total RNA, C. elegans were exposed to 20 mg of bacterial lawn in NGN agar for 24 h.
Project description:D-Glucosamine (2-amino-2-deoxy-D-glucose, C.A.S.# 3416-24-8) (GlcN) is a freely available and commonly used dietary supplement possibly promoting cartilage health in humans which also acts as an inhibitor of glycolysis. We here find that GlcN extends C. elegans lifespan by impairing glucose metabolism to activate AMP-activated protein kinase (AMPK/AAK2) leading to increased mitochondrial biogenesis. Consistent with the concept of mitohormesis, this promotes increased formation of mitochondrial reactive oxygen species (ROS) and p38/PMK-1-mediated stress signaling culminating in increased expression of the nematodal amino acid-transporter 1 (aat-1) gene. Ameliorating mitochondrial ROS formation as well as impairment of aat-1-expression abolishes GlcN-mediated lifespan extension in a NRF2/SKN-1-dependent fashion. Notably and unlike other calorie restriction mimetics (CRM) like 2-deoxy-D-glucose (2DG, DOG), GlcN extends lifespan of aging C57BL/6 mice (log-rank: p=0.002; cox regression: p=0.01) similarly paralleled by an induction of mitochondrial biogenesis, increased expression of several murine amino acid transporters, as well as increased amino-acid catabolism. Taken together, GlcN mimics a ketogenic diet to extend healthspan in evolutionary distinct species.
Project description:In the present study, we investigated the effect of CBM 588 on lifespan and multiple-stress resistance using Caenorhabditis elegans as a model animal. When adult C. elegans were fed a standard diet of Escherichia coli OP50 or CBM 588, the lifespan of the animals fed CBM 588 was significantly longer than that of animals fed OP50. Moreover, the worms fed CBM 588 were more resistant to certain stressors, including infections with pathogenic bacteria, UV irradiation, and the metal stressor Cu2+. CBM 588 failed to extend the lifespan of the daf-2/IR, daf-16/FOXO and skn-1/Nrf2 mutants. Transcriptional profiling comparing CBM 588-fed and control-fed animals suggested that DAF-16-dependent class II genes were regulated by CBM 588. In conclusion, CBM 588 extends the lifespan of C. elegans probably through regulation of the insulin/IGF-1 signaling (IIS) pathway and the Nrf2 transcription factor, and CBM 588 improves resistance to several stressors in C. elegans.