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1.
Mol Cell ; 73(4): 775-787.e10, 2019 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-30642763

RESUMEN

Little information is available about how post-transcriptional mechanisms regulate the aging process. Here, we show that the RNA-binding protein Pumilio2 (PUM2), which is a translation repressor, is induced upon aging and acts as a negative regulator of lifespan and mitochondrial homeostasis. Multi-omics and cross-species analyses of PUM2 function show that it inhibits the translation of the mRNA encoding for the mitochondrial fission factor (Mff), thereby impairing mitochondrial fission and mitophagy. This mechanism is conserved in C. elegans by the PUM2 ortholog PUF-8. puf-8 knock-down in old nematodes and Pum2 CRISPR/Cas9-mediated knockout in the muscles of elderly mice enhances mitochondrial fission and mitophagy in both models, hence improving mitochondrial quality control and tissue homeostasis. Our data reveal how a PUM2-mediated layer of post-transcriptional regulation links altered Mff translation to mitochondrial dynamics and mitophagy, thereby mediating age-related mitochondrial dysfunctions.


Asunto(s)
Envejecimiento/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Mitocondrias/metabolismo , Dinámicas Mitocondriales , Mitofagia , Proteínas de Unión al ARN/metabolismo , Factores de Edad , Envejecimiento/genética , Envejecimiento/patología , Animales , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Femenino , Células HEK293 , Células HeLa , Humanos , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones Endogámicos C57BL , Mitocondrias/genética , Mitocondrias/patología , Mitocondrias Musculares/metabolismo , Mitocondrias Musculares/patología , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Proteínas de Unión al ARN/genética , Transducción de Señal , Regulación hacia Arriba
2.
Calcif Tissue Int ; 114(1): 53-59, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37925671

RESUMEN

The age-related loss of skeletal muscle function starts from midlife and if left unaddressed can lead to an impaired quality of life. A growing body of evidence indicates that mitochondrial dysfunction is causally involved with muscle aging. Muscles are tissues with high metabolic requirements, and contain rich mitochondria supply to support their continual energy needs. Cellular mitochondrial health is maintained by expansing of the mitochondrial pool though mitochondrial biogenesis, by preserving the natural mitochondrial dynamic process, via fusion and fission, and by ensuring the removal of damaged mitochondria through mitophagy. During aging, mitophagy levels decline and negatively impact skeletal muscle performance. Nutritional and pharmacological approaches have been proposed to manage the decline in muscle function due to impaired mitochondria bioenergetics. The natural postbiotic Urolithin A has been shown to promote mitophagy, mitochondrial function and improved muscle function across species in different experimental models and across multiple clinical studies. In this review, we explore the biology of Urolithin A and the clinical evidence of its impact on promoting healthy skeletal muscles during age-associated muscle decline.


Asunto(s)
Cumarinas , Mitofagia , Calidad de Vida , Músculo Esquelético
3.
EMBO J ; 38(19): e101704, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31429971

RESUMEN

The TRAnsport Protein Particle (TRAPP) complex controls multiple membrane trafficking steps and is strategically positioned to mediate cell adaptation to diverse environmental conditions, including acute stress. We have identified the TRAPP complex as a component of a branch of the integrated stress response that impinges on the early secretory pathway. The TRAPP complex associates with and drives the recruitment of the COPII coat to stress granules (SGs) leading to vesiculation of the Golgi complex and arrest of ER export. The relocation of the TRAPP complex and COPII to SGs only occurs in cycling cells and is CDK1/2-dependent, being driven by the interaction of TRAPP with hnRNPK, a CDK substrate that associates with SGs when phosphorylated. In addition, CDK1/2 inhibition impairs TRAPP complex/COPII relocation to SGs while stabilizing them at ER exit sites. Importantly, the TRAPP complex controls the maturation of SGs. SGs that assemble in TRAPP-depleted cells are smaller and are no longer able to recruit RACK1 and Raptor, two TRAPP-interactive signaling proteins, sensitizing cells to stress-induced apoptosis.


Asunto(s)
Vesículas Cubiertas por Proteínas de Revestimiento/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Estrés Fisiológico , Animales , Proteína Quinasa CDC2/metabolismo , Línea Celular , Quinasa 2 Dependiente de la Ciclina/metabolismo , Retículo Endoplásmico/metabolismo , Células HeLa , Humanos , Ratas
4.
Nature ; 552(7684): 187-193, 2017 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-29211722

RESUMEN

Alzheimer's disease is a common and devastating disease characterized by aggregation of the amyloid-ß peptide. However, we know relatively little about the underlying molecular mechanisms or how to treat patients with Alzheimer's disease. Here we provide bioinformatic and experimental evidence of a conserved mitochondrial stress response signature present in diseases involving amyloid-ß proteotoxicity in human, mouse and Caenorhabditis elegans that involves the mitochondrial unfolded protein response and mitophagy pathways. Using a worm model of amyloid-ß proteotoxicity, GMC101, we recapitulated mitochondrial features and confirmed that the induction of this mitochondrial stress response was essential for the maintenance of mitochondrial proteostasis and health. Notably, increasing mitochondrial proteostasis by pharmacologically and genetically targeting mitochondrial translation and mitophagy increases the fitness and lifespan of GMC101 worms and reduces amyloid aggregation in cells, worms and in transgenic mouse models of Alzheimer's disease. Our data support the relevance of enhancing mitochondrial proteostasis to delay amyloid-ß proteotoxic diseases, such as Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/toxicidad , Homeostasis , Mitocondrias/metabolismo , Proteostasis , Enfermedad de Alzheimer/genética , Animales , Caenorhabditis elegans/genética , Modelos Animales de Enfermedad , Homeostasis/efectos de los fármacos , Humanos , Masculino , Memoria/fisiología , Ratones , Ratones Transgénicos , Mitocondrias/efectos de los fármacos , Mitocondrias/genética , Mitocondrias/patología , Mitofagia/efectos de los fármacos , Mitofagia/genética , NAD/metabolismo , Niacinamida/análogos & derivados , Niacinamida/farmacología , Fosforilación Oxidativa , Agregación Patológica de Proteínas/tratamiento farmacológico , Biosíntesis de Proteínas/efectos de los fármacos , Proteostasis/efectos de los fármacos , Compuestos de Piridinio , Respuesta de Proteína Desplegada/genética
5.
Trends Biochem Sci ; 42(9): 712-725, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28579074

RESUMEN

Mitochondrial stress requires timely intervention to prevent mitochondrial and cellular dysfunction. Re-establishing the correct protein homeostasis is crucial for coping with mitochondrial stress and maintaining cellular homeostasis. The best-characterized adaptive pathways for mitochondrial stress involve a signal originating from stressed mitochondria that triggers a nuclear response. However, recent findings have shown that mitochondrial stress also affects a complex network of protein homeostasis pathways in the cytosol. We review how mitochondrial dysregulation affects cytosolic proteostasis by regulating the quantity and quality of protein synthesis, protein stability, and protein degradation, leading to an integrated regulation of cellular metabolism and proliferation. This mitochondria to cytosol network extends the current model of the mitochondrial stress response, with potential applications in the treatment of mitochondrial disease.


Asunto(s)
Citosol/metabolismo , Homeostasis , Mitocondrias/metabolismo , Proteínas/metabolismo , Estrés Fisiológico , Animales , Humanos
6.
Hum Mol Genet ; 26(3): 582-598, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28053050

RESUMEN

To understand the cause of Parkinson's disease (PD), it is important to determine the functional interactions between factors linked to the disease. Parkin is associated with autosomal recessive early-onset PD, and controls the transcription of PGC-1α, a master regulator of mitochondrial biogenesis. These two factors functionally interact to regulate the turnover and quality of mitochondria, by increasing both mitophagic activity and mitochondria biogenesis. In cortical neurons, co-expressing PGC-1α and Parkin increases the number of mitochondria, enhances maximal respiration, and accelerates the recovery of the mitochondrial membrane potential following mitochondrial uncoupling. PGC-1α enhances Mfn2 transcription, but also leads to increased degradation of the Mfn2 protein, a key ubiquitylation target of Parkin on mitochondria. In vivo, Parkin has significant protective effects on the survival and function of nigral dopaminergic neurons in which the chronic expression of PGC-1α is induced. Ultrastructural analysis shows that these two factors together control the density of mitochondria and their interaction with the endoplasmic reticulum. These results highlight the combined effects of Parkin and PGC-1α in the maintenance of mitochondrial homeostasis in dopaminergic neurons. These two factors synergistically control the quality and function of mitochondria, which is important for the survival of neurons in Parkinson's disease.


Asunto(s)
GTP Fosfohidrolasas/genética , Mitocondrias/genética , Proteínas Mitocondriales/genética , Trastornos Parkinsonianos/genética , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Ubiquitina-Proteína Ligasas/genética , Neuronas Dopaminérgicas/metabolismo , Neuronas Dopaminérgicas/patología , Neuronas Dopaminérgicas/ultraestructura , Retículo Endoplásmico/genética , Retículo Endoplásmico/metabolismo , Regulación de la Expresión Génica , Humanos , Potencial de la Membrana Mitocondrial/genética , Mitocondrias/patología , Mitocondrias/ultraestructura , Biogénesis de Organelos , Estrés Oxidativo/genética , Trastornos Parkinsonianos/metabolismo , Trastornos Parkinsonianos/patología , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Proteolisis , Ubiquitina-Proteína Ligasas/metabolismo
7.
EMBO J ; 34(2): 200-17, 2015 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-25476449

RESUMEN

Hedgehog signaling is essential for tissue development and stemness, and its deregulation has been observed in many tumors. Aberrant activation of Hedgehog signaling is the result of genetic mutations of pathway components or other Smo-dependent or independent mechanisms, all triggering the downstream effector Gli1. For this reason, understanding the poorly elucidated mechanism of Gli1-mediated transcription allows to identify novel molecules blocking the pathway at a downstream level, representing a critical goal in tumor biology. Here, we clarify the structural requirements of the pathway effector Gli1 for binding to DNA and identify Glabrescione B as the first small molecule binding to Gli1 zinc finger and impairing Gli1 activity by interfering with its interaction with DNA. Remarkably, as a consequence of its robust inhibitory effect on Gli1 activity, Glabrescione B inhibited the growth of Hedgehog-dependent tumor cells in vitro and in vivo as well as the self-renewal ability and clonogenicity of tumor-derived stem cells. The identification of the structural requirements of Gli1/DNA interaction highlights their relevance for pharmacologic interference of Gli signaling.


Asunto(s)
ADN/metabolismo , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Isoflavonas/farmacología , Factores de Transcripción de Tipo Kruppel/metabolismo , Receptores de Superficie Celular/fisiología , Transducción de Señal/efectos de los fármacos , Animales , Cerebelo/citología , Cerebelo/efectos de los fármacos , Cerebelo/metabolismo , ADN/efectos de los fármacos , Embrión de Mamíferos/citología , Embrión de Mamíferos/efectos de los fármacos , Embrión de Mamíferos/metabolismo , Células Madre Embrionarias/citología , Células Madre Embrionarias/efectos de los fármacos , Células Madre Embrionarias/metabolismo , Femenino , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Glioblastoma/metabolismo , Factores de Transcripción de Tipo Kruppel/química , Factores de Transcripción de Tipo Kruppel/genética , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Simulación de Dinámica Molecular , Mutagénesis Sitio-Dirigida , Mutación/genética , Receptores Patched , Receptores Acoplados a Proteínas G/metabolismo , Receptor Smoothened , Proteína con Dedos de Zinc GLI1
8.
Int J Mol Sci ; 18(4)2017 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-28422076

RESUMEN

Toxicity is one of the major attrition causes during the drug development process. In that line, cardio-, neuro-, and hepatotoxicities are among the main reasons behind the retirement of drugs in clinical phases and post market withdrawal. Zebrafish exploitation in high-throughput drug screening is becoming an important tool to assess the toxicity and efficacy of novel drugs. This animal model has, from early developmental stages, fully functional organs from a physiological point of view. Thus, drug-induced organ-toxicity can be detected in larval stages, allowing a high predictive power on possible human drug-induced liabilities. Hence, zebrafish can bridge the gap between preclinical in vitro safety assays and rodent models in a fast and cost-effective manner. ZeGlobalTox is an innovative assay that sequentially integrates in vivo cardio-, neuro-, and hepatotoxicity assessment in the same animal, thus impacting strongly in the 3Rs principles. It Reduces, by up to a third, the number of animals required to assess toxicity in those organs. It Refines the drug toxicity evaluation through novel physiological parameters. Finally, it might allow the Replacement of classical species, such as rodents and larger mammals, thanks to its high predictivity (Specificity: 89%, Sensitivity: 68% and Accuracy: 78%).


Asunto(s)
Evaluación Preclínica de Medicamentos/métodos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Pruebas de Toxicidad , Animales , Cardiotoxicidad , Hígado/efectos de los fármacos , Hígado/patología , Locomoción/efectos de los fármacos , Modelos Animales , Especificidad de Órganos/efectos de los fármacos , Pruebas de Toxicidad Aguda , Pez Cebra
9.
J Neurosci ; 33(38): 15259-71, 2013 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-24048855

RESUMEN

Panic attacks are a hallmark in panic disorder (PAND). During the panic attack, a strong association with the surrounding context is established suggesting that the hippocampus may be critically involved in the pathophysiology of PAND, given its role in contextual processing. We previously showed that variation in the expression of the neurotrophin tyrosine kinase receptor type 3 (NTRK3) in both PAND patients and a transgenic mouse model (TgNTRK3) may have a role in PAND pathophysiology. Our study examines hippocampal function and activation of the brain fear network in TgNTRK3 mice. TgNTRK3 mice showed increased fear memories accompanied by impaired extinction, congruent with an altered activation pattern of the amygdala-hippocampus-medial prefrontal cortex fear circuit. Moreover, TgNTRK3 mice also showed an unbalanced excitation-to-inhibition ratio in the hippocampal cornu ammonis 3 (CA3)-CA1 subcircuit toward hyperexcitability. The resulting hippocampal hyperexcitability underlies the enhanced fear memories, as supported by the efficacy of tiagabine, a GABA reuptake inhibitor, to rescue fear response. The fearful phenotype appears to be the result of hippocampal hyperexcitability and aberrant fear circuit activation. We conclude that NTRK3 plays a role in PAND by regulating hippocampus-dependent fear memories.


Asunto(s)
Miedo , Hipocampo/fisiopatología , Memoria/fisiología , Trastorno de Pánico , Receptor trkC/genética , Análisis de Varianza , Animales , Proteínas Bacterianas/genética , Condicionamiento Clásico/efectos de los fármacos , Condicionamiento Clásico/fisiología , Modelos Animales de Enfermedad , Homólogo 4 de la Proteína Discs Large , Antagonistas de Aminoácidos Excitadores/farmacología , Conducta Exploratoria/efectos de los fármacos , Conducta Exploratoria/fisiología , Extinción Psicológica/efectos de los fármacos , Extinción Psicológica/fisiología , Agonistas del GABA/farmacología , Generalización Psicológica/efectos de los fármacos , Generalización Psicológica/fisiología , Glutamato Descarboxilasa/metabolismo , Guanilato-Quinasas/metabolismo , Hipocampo/efectos de los fármacos , Proteínas Luminiscentes/genética , Aprendizaje por Laberinto/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Memoria/efectos de los fármacos , Ratones , Ratones Transgénicos , Ácidos Nipecóticos/farmacología , Trastorno de Pánico/genética , Trastorno de Pánico/patología , Trastorno de Pánico/fisiopatología , Piperidinas/farmacología , Proteínas Proto-Oncogénicas c-fos/metabolismo , Tiagabina , Proteínas de Transporte Vesicular de Glutamato/metabolismo
10.
Methods Mol Biol ; 2814: 45-53, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38954196

RESUMEN

Eukaryotic cells have been constantly challenged throughout their evolution by pathogens, mechanical stresses, or toxic compounds that induce plasma membrane (PM) or endolysosomal membrane damage. The survival of the wounded cells depends on damage detection and repair machineries that are evolutionary conserved between protozoan, plants, and animals. We use the social amoeba Dictyostelium discoideum as a model system to study bacteria, mechanical or sterile membrane damage that allows us to identify and monitor factors involved in PM, endolysosomal damage response (ELDR), and endolysosomal homeostasis. Importantly, the sterile damage techniques presented here homogenously affect cell populations, which allows to phenotype mutant strains and quantify various aspects of cell fitness using live cell microscopy. This is instrumental to functionally assess genes involved in the repair of damaged plasma membrane or intracellular compartments and the degradation of extensively damaged compartments. Here, we describe how to inflict sterile PM or endolysosomal membrane damage, how to monitor the cell-intrinsic response to damage, and how to proxy proton leakage from damaged acidic compartments and quantify cell viability.


Asunto(s)
Membrana Celular , Dictyostelium , Lisosomas , Dictyostelium/genética , Dictyostelium/metabolismo , Membrana Celular/metabolismo , Lisosomas/metabolismo , Supervivencia Celular
11.
Ann Ital Chir ; 94: 329-331, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37794823

RESUMEN

Scopo di questa trattazione è quello di fare una disamina conoscitiva dei personaggi, dei fatti e dei tempi in cui la chirurgia di questo ultimo secolo si è sviluppata ed ha acquisito la dignità di essere considerata "scienza" fino a raggiungere quella bellezza esecutiva che si riscontra solo nell'arte. Maestri del bisturi dunque e del sapere, non più praticanti come erano nei secoli dell'alto Medioevo. Infatti la tecnica e la tecnologia Chirurgica di oggi con le loro grandi conquiste hanno improntato, o meglio rivoluzionato, tutta la storia di questa disciplina entrando alla metà del XX secolo come ausilio del chirurgo e ed oggi diventate protagoniste assolute della Chirurgia stessa. Ed i Chirurghi? Da grandi interpreti "solisti" sono diventati "dipendenti" dalle tecnologie sempre più imperanti e co-gestori della disciplina nella sua complessità.

12.
Nat Metab ; 5(12): 2047-2061, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38036770

RESUMEN

Maintaining optimal mitochondrial function is a feature of health. Mitophagy removes and recycles damaged mitochondria and regulates the biogenesis of new, fully functional ones preserving healthy mitochondrial functions and activities. Preclinical and clinical studies have shown that impaired mitophagy negatively affects cellular health and contributes to age-related chronic diseases. Strategies to boost mitophagy have been successfully tested in model organisms, and, recently, some have been translated into clinics. In this Review, we describe the basic mechanisms of mitophagy and how mitophagy can be assessed in human blood, the immune system and tissues, including muscle, brain and liver. We outline mitophagy's role in specific diseases and describe mitophagy-activating approaches successfully tested in humans, including exercise and nutritional and pharmacological interventions. We describe how mitophagy is connected to other features of ageing through general mechanisms such as inflammation and oxidative stress and forecast how strengthening research on mitophagy and mitophagy interventions may strongly support human health.


Asunto(s)
Envejecimiento , Mitofagia , Humanos , Mitofagia/fisiología , Envejecimiento/fisiología , Mitocondrias/metabolismo , Estrés Oxidativo
13.
Cell Rep Med ; 3(5): 100633, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35584623

RESUMEN

Targeting mitophagy to activate the recycling of faulty mitochondria during aging is a strategy to mitigate muscle decline. We present results from a randomized, placebo-controlled trial in middle-aged adults where we administer a postbiotic compound Urolithin A (Mitopure), a known mitophagy activator, at two doses for 4 months (NCT03464500). The data show significant improvements in muscle strength (∼12%) with intake of Urolithin A. We observe clinically meaningful improvements with Urolithin A on aerobic endurance (peak oxygen oxygen consumption [VO2]) and physical performance (6 min walk test) but do not notice a significant improvement on peak power output (primary endpoint). Levels of plasma acylcarnitines and C-reactive proteins are significantly lower with Urolithin A, indicating higher mitochondrial efficiency and reduced inflammation. We also examine expression of proteins linked to mitophagy and mitochondrial metabolism in skeletal muscle and find a significant increase with Urolithin A administration. This study highlights the benefit of Urolithin A to improve muscle performance.


Asunto(s)
Mitofagia , Fuerza Muscular , Biomarcadores , Cumarinas , Mitocondrias
14.
Aging Cell ; 21(8): e13662, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35778837

RESUMEN

Osteoarthritis (OA) is the most common age-related joint disorder with no effective therapy. According to the World Health Organization, OA affects over 500 million people and is characterized by degradation of cartilage and other joint tissues, severe pain, and impaired mobility. Mitochondrial dysfunction contributes to OA pathology. However, interventions to rescue mitochondrial defects in human OA are not available. Urolithin A (Mitopure) is a natural postbiotic compound that promotes mitophagy and mitochondrial function and beneficially impacts muscle health in preclinical models of aging and in elderly and middle-aged humans. Here, we showed that Urolithin A improved mitophagy and mitochondrial respiration in primary chondrocytes from joints of both healthy donors and OA patients. Furthermore, Urolithin A reduced disease progression in a mouse model of OA, decreasing cartilage degeneration, synovial inflammation, and pain. These improvements were associated with increased mitophagy and mitochondrial content, in joints of OA mice. These findings indicate that UA promotes joint mitochondrial health, alleviates OA pathology, and supports Urolithin A's potential to improve mobility with beneficial effects on structural damage in joints.


Asunto(s)
Cartílago Articular , Osteoartritis de la Rodilla , Anciano , Animales , Cartílago Articular/metabolismo , Condrocitos/metabolismo , Cumarinas , Humanos , Ratones , Persona de Mediana Edad , Mitocondrias/metabolismo , Osteoartritis de la Rodilla/tratamiento farmacológico , Osteoartritis de la Rodilla/metabolismo , Osteoartritis de la Rodilla/patología , Dolor/metabolismo
15.
JAMA Netw Open ; 5(1): e2144279, 2022 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-35050355

RESUMEN

Importance: Aging is associated with a decline in mitochondrial function and reduced exercise capacity. Urolithin A is a natural gut microbiome-derived food metabolite that has been shown to stimulate mitophagy and improve muscle function in older animals and to induce mitochondrial gene expression in older humans. Objective: To investigate whether oral administration of urolithin A improved the 6-minute walk distance, muscle endurance in hand and leg muscles, and biomarkers associated with mitochondrial and cellular health. Design, Setting, and Participants: This double-blind, placebo-controlled randomized clinical trial in adults aged 65 to 90 years was conducted at a medical center and a cancer research center in Seattle, Washington, from March 1, 2018, to July 30, 2020. Muscle fatigue tests and plasma analysis of biomarkers were assessed at baseline, 2 months, and 4 months. Six-minute walk distance and maximal ATP production were assessed using magnetic resonance spectroscopy at baseline and at the end of study at 4 months. The analysis used an intention-to-treat approach. Interventions: Participants were randomized to receive daily oral supplementation with either 1000 mg urolithin A or placebo for 4 months. Main Outcomes and Measures: The primary end point was change from baseline in the 6-minute walk distance and change from baseline to 4 months in maximal ATP production in the hand skeletal muscle. The secondary end points were change in muscle endurance of 2 skeletal muscles (tibialis anterior [TA] in the leg and first dorsal interosseus [FDI] in the hand). Cellular health biomarkers were investigated via plasma metabolomics. Adverse events were recorded and compared between the 2 groups during the intervention period. Results: A total of 66 participants were randomized to either the urolithin A (n = 33) or the placebo (n = 33) intervention group. These participants had a mean (SD) age of 71.7 (4.94) years, were predominantly women (50 [75.8%]), and were all White individuals. Urolithin A, compared with placebo, significantly improved muscle endurance (ie, increase in the number of muscle contractions until fatigue from baseline) in the FDI and TA at 2 months (urolithin A: FDI, 95.3 [115.5] and TA, 41.4 [65.5]; placebo: FDI, 11.6 [147.4] and TA, 5.7 [127.1]). Plasma levels of several acylcarnitines, ceramides, and C-reactive protein were decreased by urolithin A, compared with placebo, at 4 months (baseline vs 4 mo: urolithin A, 2.14 [2.15] vs 2.07 [1.46]; placebo, 2.17 [2.52] vs 2.65 [1.86]). The mean (SD) increase from baseline in the 6-minute walk distance was 60.8 (67.2) m in the urolithin A group and 42.5 (73.3) m in the placebo group. The mean (SD) change from baseline to 4 months in maximal ATP production in the FDI was 0.07 (0.23) mM/s in the urolithin A group and 0.06 (0.20) mM/s in the placebo group; for the TA, it was -0.03 (0.10) mM/s in the urolithin A group and 0.03 (0.10) mM/s in the placebo group. These results showed no significant improvement with urolithin A supplementation compared with placebo. No statistical differences in adverse events were observed between the 2 groups. Conclusions and Relevance: This randomized clinical trial found that urolithin A supplementation was safe and well tolerated in the assessed population. Although the improvements in the 6-minute walk distance and maximal ATP production in the hand muscle were not significant in the urolithin A group vs the placebo group, long-term urolithin A supplementation was beneficial for muscle endurance and plasma biomarkers, suggesting that urolithin A may counteract age-associated muscle decline; however, future work is needed to confirm this finding. Trial Registration: ClinicalTrials.gov Identifier: NCT03283462.


Asunto(s)
Cumarinas/uso terapéutico , Suplementos Dietéticos , Músculo Esquelético/metabolismo , Capacidad Vital/efectos de los fármacos , Prueba de Paso , Adulto , Antioxidantes/uso terapéutico , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Caminata
16.
Eur J Clin Nutr ; 76(2): 297-308, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34117375

RESUMEN

BACKGROUND: Urolithin A (UA) is produced by gut microflora from foods rich in ellagitannins. UA has been shown to improve mitochondrial health preclinically and in humans. Not everyone has a microbiome capable of producing UA, making supplementation with UA an appealing strategy. OBJECTIVE: This is the first detailed investigation of the prevalence of UA producers in a healthy population and the ability of direct UA supplementation to overcome both microbiome and dietary variability. Dietary intake of a glass of pomegranate juice (PJ) was used to assess UA producer status (n = 100 participants) and to characterize differences in gut microbiome between UA producers from non-producers. METHODS: Subjects were randomized (1:1) to either PJ or a food product containing UA (500 mg). Prevalence of UA producers and non-producers were determined in the PJ group. Diet questionnaires and fecal samples were collected to compare differences between UA producers and non-producers along with plasma samples at different time points to assess levels of UA and its conjugates between the interventions. RESULTS: Only 12% of subjects had detectable levels of UA at baseline. Following PJ intake ~40% of the subjects converted significantly the precursor compounds into UA. UA producers were distinguished by a significantly higher gut microbiome diversity and ratio of Firmicutes to Bacteroides. Direct supplementation with UA significantly increased plasma levels and provided a >6-fold exposure to UA vs. PJ (p < 0.0001). CONCLUSIONS: Differences in gut microbiome and diet that dictate natural exposure to UA can be overcome via direct dietary UA supplementation.


Asunto(s)
Microbioma Gastrointestinal , Adulto , Cumarinas/farmacología , Exposición Dietética , Suplementos Dietéticos , Humanos
17.
J Clin Invest ; 132(17)2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35787521

RESUMEN

Mitohormesis defines the increase in fitness mediated by adaptive responses to mild mitochondrial stress. Tetracyclines inhibit not only bacterial but also mitochondrial translation, thus imposing a low level of mitochondrial stress on eukaryotic cells. We demonstrate in cell and germ-free mouse models that tetracyclines induce a mild adaptive mitochondrial stress response (MSR), involving both the ATF4-mediated integrative stress response and type I interferon (IFN) signaling. To overcome the interferences of tetracyclines with the host microbiome, we identify tetracycline derivatives that have minimal antimicrobial activity, yet retain full capacity to induce the MSR, such as the lead compound, 9-tert-butyl doxycycline (9-TB). The MSR induced by doxycycline (Dox) and 9-TB improves survival and disease tolerance against lethal influenza virus (IFV) infection when given preventively. 9-TB, unlike Dox, did not affect the gut microbiome and also showed encouraging results against IFV when given in a therapeutic setting. Tolerance to IFV infection is associated with the induction of genes involved in lung epithelial cell and cilia function, and with downregulation of inflammatory and immune gene sets in lungs, liver, and kidneys. Mitohormesis induced by non-antimicrobial tetracyclines and the ensuing IFN response may dampen excessive inflammation and tissue damage during viral infections, opening innovative therapeutic avenues.


Asunto(s)
Gripe Humana , Infecciones por Orthomyxoviridae , Animales , Antibacterianos , Doxiciclina/farmacología , Humanos , Gripe Humana/tratamiento farmacológico , Ratones , Tetraciclina , Tetraciclinas/farmacología
18.
Nat Aging ; 2(12): 1159-1175, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-37118545

RESUMEN

Age-related muscle dysfunction and sarcopenia are major causes of physical incapacitation in older adults and currently lack viable treatment strategies. Here we find that sphingolipids accumulate in mouse skeletal muscle upon aging and that both genetic and pharmacological inhibition of sphingolipid synthesis prevent age-related decline in muscle mass while enhancing strength and exercise capacity. Inhibition of sphingolipid synthesis confers increased myogenic potential and promotes protein synthesis. Within the sphingolipid pathway, we show that accumulation of dihydroceramides is the culprit disturbing myofibrillar homeostasis. The relevance of sphingolipid pathways in human aging is demonstrated in two cohorts, the UK Biobank and Helsinki Birth Cohort Study in which gene expression-reducing variants of SPTLC1 and DEGS1 are associated with improved and reduced fitness of older individuals, respectively. These findings identify sphingolipid synthesis inhibition as an attractive therapeutic strategy for age-related sarcopenia and co-occurring pathologies.


Asunto(s)
Sarcopenia , Animales , Ratones , Humanos , Anciano , Sarcopenia/prevención & control , Músculo Esquelético/metabolismo , Esfingolípidos/metabolismo , Estudios de Cohortes , Envejecimiento/genética
19.
Hepatogastroenterology ; 58(105): 69-75, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21510289

RESUMEN

UNLABELLED: BACKGROUND\ AIMS: Helicobacter Pylori (H. Pylori) is a key pathogenetic factor in gastritis, peptic ulcer disease, gastric carcinoma and lymphoma but its relationship with gastroesophageal reflux disease (GERD) is controversial. The aim of the study is to estimate the possible association between the presence of H. pylori and GERD. METHODOLOGY: In this retrospective study we examined the endoscopy and pathology reports of all the 638 consecutive patients who had upper gastrointestinal endoscopy and adequate mucosal sampling in 2005 in our department at the University of Padova. Yates corrected chi2 test was used to compare the H. Pylori frequency in the different histological groups. Multinomial logistic regression was used to identify possible predictors of H. Pylori infection. RESULTS: In this selected population 133 patients were affected by H. Pylori infection (20.8%) and 107 were affected by GERD according to Montreal definition. No significant relation between H. Pylori infection and GERD or NERD (non erosive reflux disease) was evidenced. As expected histological gastritis at the examination confirmed to be the strongest predictor of infection with a odds ratio of 39.4 (95% CI 5.4-287.4, p < 0.01). Upper abdominal pain showed to be the only clinical independent predictors for the presence of H. Pylori infection with a odds ratio of 1.5 (95% CI 1.0-2.3, p = 0.04). CONCLUSIONS: Our study showed that in north eastern Italy there is no association between H. Pylori infection and GERD. On the contrary presence of histological gastritis and upper abdominal pain were confirmed to be significant predictors of H. Pylori infection. No endoscopic characteristic is significantly related to the presence of H. Pylori.


Asunto(s)
Reflujo Gastroesofágico/microbiología , Infecciones por Helicobacter/complicaciones , Helicobacter pylori , Dolor Abdominal/epidemiología , Dolor Abdominal/microbiología , Adulto , Anciano , Distribución de Chi-Cuadrado , Estudios Transversales , Esofagoscopía , Gastritis/epidemiología , Gastritis/microbiología , Reflujo Gastroesofágico/epidemiología , Infecciones por Helicobacter/epidemiología , Humanos , Italia/epidemiología , Modelos Logísticos , Persona de Mediana Edad , Estudios Retrospectivos
20.
Lasers Med Sci ; 26(2): 223-8, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20821340

RESUMEN

Different ablation techniques have been utilized in the treatment of Barrett's esophagus (BE) to reduce the risk of degeneration. Treatment complications, risk of recurrence, and buried intestinal metaplasia (IM) are all major concerns. The effect of diode laser treatment on BE, studied in a group of patients over a long-term period, is presented here. All patients with histology of IM or low-grade dysplasia (LGD) treated with diode laser therapy for BE and followed for at least 24 months were included in the study. Treatment sessions were carried out every 3 months and bioptic follow-up examinations were done yearly. Patients without antireflux surgery received proton pump inhibitors. A total of 20 patients with IM, four of them with LGD, were treated with 161 laser sessions (in mean eight per patient) without complications. Complete, sustained endoscopic and histologic remission was obtained in 13 patients (11/12 with BE ≤ 3 cm and 2/8 with BE >3 cm, p < 0.01) and a mean of 83 ± 27% of the metaplasic tissue was removed in all the patients. All four cases of LGD healed to squamous tissue. No buried metaplasia, recurrences, or disease progressions were reported after a mean follow-up of 6 years and 2 months. Diode laser ablation is a safe and effective method in most cases of short BE, while it is less effective in the long form, requiring a large number of sessions. Long-term results show that the risk of recurrence and of buried intestinal metaplasia underneath neosquamous epithelium is negligible.


Asunto(s)
Esófago de Barrett/terapia , Terapia por Láser , Adulto , Anciano , Esófago de Barrett/diagnóstico , Esófago de Barrett/patología , Esofagoscopía , Femenino , Humanos , Láseres de Semiconductores , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
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