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1.
Nutrients ; 16(13)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38999870

RESUMEN

Investigations into human longevity are increasingly focusing on healthspan enhancement, not just lifespan extension. Lifestyle modifications and nutritional choices, including food supplements, can significantly affect aging and general health. Phytochemicals in centenarians' diets, such as those found in Timut pepper, a Nepalese spice with various medicinal properties, may contribute to their longevity. Similarly, Sichuan pepper, a related species, has demonstrated anti-inflammatory and neuroprotective activities. With the broader purpose of uncovering a novel treatment to address aging and its comorbidities, this study aims to investigate the potential lifespan- and healthspan-promoting effects of Timut pepper using the model organism Caenorhabditis elegans. We show that Timut pepper extract extends C. elegans' lifespan at different maintenance temperatures and increases the proportion of active nematodes in their early adulthood. In addition, we show that Timut pepper extract enhances speed and distance moved as the nematodes age. Finally, Timut pepper extract assures extracellular matrix homeostasis by slowing the age-dependent decline of collagen expression.


Asunto(s)
Caenorhabditis elegans , Capsicum , Colágeno , Longevidad , Extractos Vegetales , Caenorhabditis elegans/efectos de los fármacos , Longevidad/efectos de los fármacos , Animales , Extractos Vegetales/farmacología , Colágeno/metabolismo , Capsicum/química , Envejecimiento/efectos de los fármacos , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/metabolismo
2.
Nat Genet ; 56(8): 1737-1749, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39039278

RESUMEN

The structural maintenance of chromosome (SMC) complexes-cohesin and condensins-are crucial for chromosome separation and compaction during cell division. During the interphase, mammalian cohesins additionally fold the genome into loops and domains. Here we show that, in Caenorhabditis elegans, a species with holocentric chromosomes, condensin I is the primary, long-range loop extruder. The loss of condensin I and its X-specific variant, condensin IDC, leads to genome-wide decompaction, chromosome mixing and disappearance of X-specific topologically associating domains, while reinforcing fine-scale epigenomic compartments. In addition, condensin I/IDC inactivation led to the upregulation of X-linked genes and unveiled nuclear bodies grouping together binding sites for the X-targeting loading complex of condensin IDC. C. elegans condensin I/IDC thus uniquely organizes holocentric interphase chromosomes, akin to cohesin in mammals, as well as regulates X-chromosome gene expression.


Asunto(s)
Adenosina Trifosfatasas , Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Proteínas de Unión al ADN , Complejos Multiproteicos , Cromosoma X , Animales , Caenorhabditis elegans/genética , Adenosina Trifosfatasas/genética , Adenosina Trifosfatasas/metabolismo , Complejos Multiproteicos/genética , Complejos Multiproteicos/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Cromosoma X/genética , Proteínas Cromosómicas no Histona/metabolismo , Proteínas Cromosómicas no Histona/genética , Cohesinas , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Interfase/genética , Genoma de los Helmintos , Genes Ligados a X , Cromosomas/genética
3.
MicroPubl Biol ; 20242024.
Artículo en Inglés | MEDLINE | ID: mdl-38947245

RESUMEN

The intersection of metabolic processes and epigenetic regulation during embryogenesis is crucial yet not fully understood. Through a candidate RNAi screen in Caenorhabditis elegans , we identified metabolic enzymes ALDO-2 and PDHB-1 as potential epigenetic regulators. Mild alteration of the chromatin remodeler LET-418 /Mi2 activity rescues embryonic lethality induced by suppressing aldo-2 or pdhb-1 , suggesting a critical role for glucose and pyruvate metabolism in chromatin remodeling during embryogenesis. Given the conservation of central metabolic pathways and chromatin modifiers across species, our findings lay the foundation for future mechanistic investigations into the interplay between epigenetics and metabolism during development and upon disease.

4.
Geroscience ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38900346

RESUMEN

Little is known about the possibility of reversing age-related biological changes when they have already occurred. To explore this, we have characterized the effects of reducing insulin/IGF-1 signaling (IIS) during old age. Reduction of IIS throughout life slows age-related decline in diverse species, most strikingly in the nematode Caenorhabditis elegans. Here we show that even at advanced ages, auxin-induced degradation of DAF-2 in single tissues, including neurons and the intestine, is still able to markedly increase C. elegans lifespan. We describe how reversibility varies among senescent changes. While senescent pathologies that develop in mid-life were not reversed, there was a rejuvenation of the proteostasis network, manifesting as a restoration of the capacity to eliminate otherwise intractable protein aggregates that accumulate with age. Moreover, resistance to several stressors was restored. These results support several new conclusions. (1) Loss of resilience is not solely a consequence of pathologies that develop in earlier life. (2) Restoration of proteostasis and resilience by inhibiting IIS is a plausible cause of the increase in lifespan. And (3), most interestingly, some aspects of the age-related transition from resilience to frailty can be reversed to a certain extent. This raises the possibility that the effect of IIS and related pathways on resilience and frailty during aging in higher animals might possess some degree of reversibility.

5.
Trends Pharmacol Sci ; 45(6): 478-489, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38777670

RESUMEN

Traf2- and Nck-interacting kinase (TNIK) has emerged as a key regulator of pathological metabolic signaling in several diseases and is a promising drug target. Originally studied for its role in cell migration and proliferation, TNIK possesses several newly identified functions that drive the pathogenesis of multiple diseases. Specifically, we evaluate TNIK's newfound roles in cancer, metabolic disorders, and neuronal function. We emphasize the implications of TNIK signaling in metabolic signaling and evaluate the translational potential of these discoveries. We also highlight how TNIK's role in many biological processes converges upon several hallmarks of aging. We conclude by discussing the therapeutic landscape of TNIK-targeting drugs and the recent success of clinical trials targeting TNIK.


Asunto(s)
Envejecimiento , Neoplasias , Proteínas Serina-Treonina Quinasas , Humanos , Neoplasias/metabolismo , Neoplasias/tratamiento farmacológico , Envejecimiento/metabolismo , Animales , Proteínas Serina-Treonina Quinasas/metabolismo , Enfermedades Metabólicas/metabolismo , Enfermedades Metabólicas/tratamiento farmacológico , Transducción de Señal
7.
Nat Commun ; 15(1): 276, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38177158

RESUMEN

Dysfunctional extracellular matrices (ECM) contribute to aging and disease. Repairing dysfunctional ECM could potentially prevent age-related pathologies. Interventions promoting longevity also impact ECM gene expression. However, the role of ECM composition changes in healthy aging remains unclear. Here we perform proteomics and in-vivo monitoring to systematically investigate ECM composition (matreotype) during aging in C. elegans revealing three distinct collagen dynamics. Longevity interventions slow age-related collagen stiffening and prolong the expression of collagens that are turned over. These prolonged collagen dynamics are mediated by a mechanical feedback loop of hemidesmosome-containing structures that span from the exoskeletal ECM through the hypodermis, basement membrane ECM, to the muscles, coupling mechanical forces to adjust ECM gene expression and longevity via the transcriptional co-activator YAP-1 across tissues. Our results provide in-vivo evidence that coordinated ECM remodeling through mechanotransduction is required and sufficient to promote longevity, offering potential avenues for interventions targeting ECM dynamics.


Asunto(s)
Proteínas de Caenorhabditis elegans , Longevidad , Animales , Longevidad/fisiología , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Mecanotransducción Celular , Matriz Extracelular/metabolismo , Colágeno/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Homeostasis , Proteínas Señalizadoras YAP , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo
8.
MicroPubl Biol ; 20242024.
Artículo en Inglés | MEDLINE | ID: mdl-38287930

RESUMEN

Numerous anti-amyloid therapies have seen recent clinical development and approval, such as the monoclonal antibodies aducanumab and lecanemab. However, in Alzheimer's disease patients, amyloid-ß (Aß) plaques are found embedded in the extracellular matrix and surrounded by collagens, which might hinder these antibodies from targeting the plaques. We reasoned that various different nutraceutical and pharmaceutical agents might induce collagen and extracellular matrix turnover and removal of these collagen-embedded amyloid-ß (Aß) plaques. To address this idea, here, we used a transgenic C. elegans strain, LSD2104 , expressing fluorescent human Aß 1-42 as an in-vivo model for secreted amyloid aggregation in the extracellular matrix. We performed a screen of various nutraceuticals and pharmaceuticals along with different combinations, and we found that quercetin 350 µM and rifampicin 75 µM successfully cleared the extracellular amyloid plaque burden compared to the 0.2% DMSO control group, with a combination of the two agents producing the maximum effect compared to either drug alone. These results may implicate the exploration of combination therapeutics of nutraceuticals and pharmaceuticals in the clearance of amyloid-ß (Aß) plaques in Alzheimer's disease.

9.
Geroscience ; 46(2): 1499-1514, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37644339

RESUMEN

Accumulation of senescent cells accelerates aging and age-related diseases, whereas preventing this accumulation extends the lifespan in mice. A characteristic of senescent cells is increased staining with ß-galactosidase (ß-gal) ex vivo. Here, we describe a progressive accumulation of ß-gal staining in the model organism C. elegans during aging. We show that distinct pharmacological and genetic interventions targeting the mitochondria and the mTORC1 to the nuclear core complex axis, the non-canonical apoptotic, and lysosomal-autophagy pathways slow the age-dependent accumulation of ß-gal. We identify a novel gene, rege-1/Regnase-1/ZC3H12A/MCPIP1, modulating ß-gal staining via the transcription factor ets-4/SPDEF. We demonstrate that knocking down Regnase-1 in human cell culture prevents senescence-associated ß-gal accumulation. Our data provide a screening pipeline to identify genes and drugs modulating senescence-associated lysosomal phenotypes.


Asunto(s)
Senescencia Celular , Endorribonucleasas , Humanos , Ratones , Animales , Senescencia Celular/genética , Endorribonucleasas/genética , Endorribonucleasas/metabolismo , Caenorhabditis elegans/genética , Biomarcadores/metabolismo , Factores de Transcripción/metabolismo , Lisosomas/metabolismo
10.
PLoS One ; 18(11): e0294859, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38032907

RESUMEN

The mammalian innate immune system is sex-dimorphic. Neutrophils are the most abundant leukocyte in humans and represent innate immunity's first line of defense. We previously found that primary mouse bone marrow neutrophils show widespread sex-dimorphism throughout life, including at the transcriptional level. Extracellular matrix [ECM]-related terms were observed among the top sex-dimorphic genes. Since the ECM is emerging as an important regulator of innate immune responses, we sought to further investigate the transcriptomic profile of primary mouse bone marrow neutrophils at both the bulk and single-cell level to understand how biological sex may influence ECM component expression in neutrophils throughout life. Here, using curated gene lists of ECM components and unbiased weighted gene co-expression network analysis [WGCNA], we find that multiple ECM-related gene sets show widespread female-bias in expression in primary mouse neutrophils. Since many immune-related diseases (e.g., rheumatoid arthritis) are more prevalent in females, our work may provide insights into the pathogenesis of sex-dimorphic inflammatory diseases.


Asunto(s)
Médula Ósea , Neutrófilos , Humanos , Ratones , Animales , Femenino , Neutrófilos/metabolismo , Leucocitos , Inmunidad Innata/genética , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Mamíferos
11.
Nat Commun ; 14(1): 6806, 2023 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-37884488

RESUMEN

Food protein amyloid fibrils have superior technological, nutritional, sensorial, and physical properties compared to native monomers, but there is as yet insufficient understanding of their digestive fate and safety for wide consumption. By combining SDS-PAGE, ELISA, fluorescence, AFM, MALDI-MS, CD, microfluidics, and SAXS techniques for the characterization of ß-lactoglobulin and lysozyme amyloid fibrils subjected to in-vitro gastrointestinal digestion, here we show that either no noticeable conformational differences exist between amyloid aggregates and their monomer counterparts after the gastrointestinal digestion process (as in ß-lactoglobulin), or that amyloid fibrils are digested significantly better than monomers (as in lysozyme). Moreover, in-vitro exposure of human cell lines and in-vivo studies with C. elegans and mouse models, indicate that the digested fibrils present no observable cytotoxicity, physiological abnormalities in health-span, nor accumulation of fibril-induced plaques in brain nor other organs. These extensive in-vitro and in-vivo studies together suggest that the digested food amyloids are at least equally as safe as those obtained from the digestion of corresponding native monomers, pointing to food amyloid fibrils as potential ingredients for human nutrition.


Asunto(s)
Amiloide , Muramidasa , Animales , Ratones , Humanos , Amiloide/metabolismo , Caenorhabditis elegans/metabolismo , Dispersión del Ángulo Pequeño , Difracción de Rayos X , Lactoglobulinas
12.
Swiss Med Wkly ; 153: 40088, 2023 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-37410895

RESUMEN

Breakthroughs in medical research in the last century have led to a significant extension of the human lifespan, resulting in a shift towards an elderly population worldwide. Due to the ongoing progress of global development towards elevated standards of living, this study specifically examines Switzerland as a representative nation to explore the socioeconomic and healthcare ramifications associated with an ageing population, thereby highlighting the tangible impact experienced in this context. Beyond the exhaustion of pension funds and medical budgets, by reviewing the literature and analysing publicly available data, we observe a "Swiss Japanification". Old age is associated with late-life comorbidities and an increasing proportion of time spent in poor health. To address these problems, a paradigm shift in medical practice is needed to improve health rather than respond to existing diseases. Basic ageing research is gaining momentum to be translated into therapeutic interventions and provides machine learning tools driving longevity medicine. We propose that research focus on closing the translational gap between the molecular mechanisms of ageing and a more prevention-based medicine, which would help people age better and prevent late-life chronic diseases.


Asunto(s)
Envejecimiento , Longevidad , Humanos , Anciano , Suiza , Atención a la Salud , Enfermedad Crónica
13.
J Cell Sci ; 136(15)2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37522320

RESUMEN

Hemidesmosomes are structural protein complexes localized at the interface of tissues with high mechanical demand and shear forces. Beyond tissue anchoring, hemidesmosomes have emerged as force-modulating structures important for translating mechanical cues into biochemical and transcriptional adaptation (i.e. mechanotransduction) across tissues. Here, we discuss the recent insights into the roles of hemidesmosomes in age-related tissue regeneration and aging in C. elegans, mice and humans. We highlight the emerging concept of preserved dynamic mechanoregulation of hemidesmosomes in tissue maintenance and healthy aging.


Asunto(s)
Proteínas de Caenorhabditis elegans , Hemidesmosomas , Humanos , Animales , Ratones , Hemidesmosomas/metabolismo , Caenorhabditis elegans/metabolismo , Longevidad , Mecanotransducción Celular , Proteínas de Caenorhabditis elegans/metabolismo
14.
Front Aging ; 4: 1172789, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37305228

RESUMEN

With an increasing aging population, the burden of age-related diseases magnifies. To alleviate this burden, geroprotection has been an area of intense research focus with the development of pharmacological interventions that target lifespan and/or healthspan. However, there are often sex differences, with compounds mostly tested in male animals. Given the importance of considering both sexes in preclinical research, this neglects potential benefits for the female population, as interventions tested in both sexes often show clear sexual dimorphisms in their biological responses. To further understand the prevalence of sex differences in pharmacological geroprotective intervention studies, we performed a systematic review of the literature according to the PRISMA guidelines. Seventy-two studies met our inclusion criteria and were classified into one of five subclasses: FDA-repurposed drugs, novel small molecules, probiotics, traditional Chinese medicine, and antioxidants, vitamins, or other dietary supplements. Interventions were analyzed for their effects on median and maximal lifespan and healthspan markers, including frailty, muscle function and coordination, cognitive function and learning, metabolism, and cancer. With our systematic review, we found that twenty-two out of sixty-four compounds tested were able to prolong both lifespan and healthspan measures. Focusing on the use of female and male mice, and on comparing their outcomes, we found that 40% of studies only used male mice or did not clarify the sex. Notably, of the 36% of pharmacologic interventions that did use both male and female mice, 73% of these studies showed sex-specific outcomes on healthspan and/or lifespan. These data highlight the importance of studying both sexes in the search for geroprotectors, as the biology of aging is not the same in male and female mice. Systematic Review Registration: [website], identifier [registration number].

15.
Biomedicines ; 11(4)2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37189830

RESUMEN

The extracellular matrix (ECM) is earning an increasingly relevant role in many disease states and aging. The analysis of these disease states is possible with the GWAS and PheWAS methodologies, and through our analysis, we aimed to explore the relationships between polymorphisms in the compendium of ECM genes (i.e., matrisome genes) in various disease states. A significant contribution on the part of ECM polymorphisms is evident in various types of disease, particularly those in the core-matrisome genes. Our results confirm previous links to connective-tissue disorders but also unearth new and underexplored relationships with neurological, psychiatric, and age-related disease states. Through our analysis of the drug indications for gene-disease relationships, we identify numerous targets that may be repurposed for age-related pathologies. The identification of ECM polymorphisms and their contributions to disease will play an integral role in future therapeutic developments, drug repurposing, precision medicine, and personalized care.

16.
Am J Physiol Cell Physiol ; 325(1): C90-C128, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37154490

RESUMEN

The extracellular matrix (ECM), composed of interlinked proteins outside of cells, is an important component of the human body that helps maintain tissue architecture and cellular homeostasis. As people age, the ECM undergoes changes that can lead to age-related morbidity and mortality. Despite its importance, ECM aging remains understudied in the field of geroscience. In this review, we discuss the core concepts of ECM integrity, outline the age-related challenges and subsequent pathologies and diseases, summarize diagnostic methods detecting a faulty ECM, and provide strategies targeting ECM homeostasis. To conceptualize this, we built a technology research tree to hierarchically visualize possible research sequences for studying ECM aging. This strategic framework will hopefully facilitate the development of future research on interventions to restore ECM integrity, which could potentially lead to the development of new drugs or therapeutic interventions promoting health during aging.


Asunto(s)
Matriz Extracelular , Longevidad , Humanos , Matriz Extracelular/metabolismo , Proteínas de la Matriz Extracelular/metabolismo , Envejecimiento , Homeostasis
17.
Int J Mol Sci ; 24(9)2023 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-37175557

RESUMEN

The mechanistic target of rapamycin (mTOR) kinase is one of the top drug targets for promoting health and lifespan extension. Besides rapamycin, only a few other mTOR inhibitors have been developed and shown to be capable of slowing aging. We used machine learning to predict novel small molecules targeting mTOR. We selected one small molecule, TKA001, based on in silico predictions of a high on-target probability, low toxicity, favorable physicochemical properties, and preferable ADMET profile. We modeled TKA001 binding in silico by molecular docking and molecular dynamics. TKA001 potently inhibits both TOR complex 1 and 2 signaling in vitro. Furthermore, TKA001 inhibits human cancer cell proliferation in vitro and extends the lifespan of Caenorhabditis elegans, suggesting that TKA001 is able to slow aging in vivo.


Asunto(s)
Proteínas de Caenorhabditis elegans , Neoplasias , Animales , Humanos , Caenorhabditis elegans/metabolismo , Longevidad , Inhibidores mTOR , Simulación del Acoplamiento Molecular , Serina-Treonina Quinasas TOR/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Sirolimus/farmacología , Proliferación Celular , Inteligencia Artificial , Neoplasias/tratamiento farmacológico
18.
Aging Dis ; 14(3): 670-693, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37191434

RESUMEN

The biomechanical properties of extracellular matrices (ECM) and their consequences for cellular homeostasis have recently emerged as a driver of aging. Here we review the age-dependent deterioration of ECM in the context of our current understanding of the aging processes. We discuss the reciprocal interactions of longevity interventions with ECM remodeling. And the relevance of ECM dynamics captured by the matrisome and the matreotypes associated with health, disease, and longevity. Furthermore, we highlight that many established longevity compounds promote ECM homeostasis. A large body of evidence for the ECM to qualify as a hallmark of aging is emerging, and the data in invertebrates is promising. However, direct experimental proof that activating ECM homeostasis is sufficient to slow aging in mammals is lacking. We conclude that further research is required and anticipate that a conceptual framework for ECM biomechanics and homeostasis will provide new strategies to promote health during aging.

19.
MicroPubl Biol ; 20232023.
Artículo en Inglés | MEDLINE | ID: mdl-37122503

RESUMEN

Transgenic overexpression of collagen col-120 increases the lifespan of C. elegans . However, whether post-developmental enhancement of collagen expression could also increase the lifespan is unknown. Recently, we described a method to induce the expression of a target gene using catalytically dead Cas9 (dCas9)-engineered C. elegans via ingestion of bacteria expressing a pair of promoter-specific single guide RNAs (sgRNA). Here, we cloned col-120 promoter-specific sgRNA oligo pair into L4440-Biobrick-sgRNA and fed these bacteria to dCas9::VP64 transgenic C. elegans . We observed a similar percentage of lifespan extension by post-developmentally dCas9-induced expression of col-120 , as previously reported through transgenic overexpression of col-120 . Consistent with this result is that induction of another previously shown longevity-promoting collagen, col-10 , also increased lifespan. Furthermore, we found an enhanced resilience to heat stress and increased expression of hsp-16.2 upon dCas9-activated col-120 expression. Together, these results provide an orthogonal method to validate longevity by enhancing col-120 expression and point towards a potential role of collagen enhancement in thermotolerance.

20.
Sci Rep ; 13(1): 4490, 2023 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-36934197

RESUMEN

Collagen has been postulated to be the most abundant protein in our body, making up one-third of the total protein content in mammals. However, a direct assessment of the total collagen levels of an entire mammal to confirm this estimate is missing. Here we measured hydroxyproline levels as a proxy for collagen content together with total protein levels of entire mice or of individual tissues. Collagen content normalized to the total protein is approximately 0.1% in the brain and liver, 1% in the heart and kidney, 4% in the muscle and lung, 6% in the colon, 20-40% in the skin, 25-35% in bones, and 40-50% in tendons of wild-type (CD1 and CB57BL/6) mice, consistent with previous reports. To our surprise, we find that collagen is approximately 12% in females and 17% in males of the total protein content of entire wild-type (CD1 and CB57BL/6) mice. Although collagen type I is the most abundant collagen, the most abundant proteins are albumin, hemoglobulin, histones, actin, serpina, and then collagen type I. Analyzing amino acid compositions of mice revealed glycine as the most abundant amino acid. Thus, we provide reference points for collagen, matrisome, protein, and amino acid composition of healthy wild-type mice.


Asunto(s)
Colágeno Tipo I , Colágeno , Animales , Femenino , Masculino , Ratones , Aminoácidos/análisis , Colágeno/química , Colágeno Tipo I/análisis , Hidroxiprolina/metabolismo , Piel/metabolismo
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