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1.
Sci Adv ; 10(33): eadn5993, 2024 Aug 16.
Article de Anglais | MEDLINE | ID: mdl-39141732

RÉSUMÉ

Skeletal muscle has gained recognition as an endocrine organ releasing myokines upon contraction during physical exercise. These myokines exert both local and pleiotropic health benefits, underscoring the crucial role of muscle function in countering obesity and contributing to the overall positive effects of exercise on health. Here, we found that exercise activates muscle p38γ, increasing locomotor activity through the secretion of interleukin-15 (IL-15). IL-15 signals in the motor cortex, stimulating locomotor activity. This activation of muscle p38γ, leading to an increase locomotor activity, plays a crucial role in reducing the risk of diabetes and liver steatosis, unveiling a vital muscle-brain communication pathway with profound clinical implications. The correlation between p38γ activation in human muscle during acute exercise and increased blood IL-15 levels highlights the potential therapeutic relevance of this pathway in treating obesity and metabolic diseases. These findings provide valuable insights into the molecular basis of exercise-induced myokine responses promoting physical activity.


Sujet(s)
Exercice physique , Interleukine-15 , Muscles squelettiques , Interleukine-15/métabolisme , Muscles squelettiques/métabolisme , Humains , Animaux , Exercice physique/physiologie , Locomotion , Souris , p38 Mitogen-Activated Protein Kinases/métabolisme , Transduction du signal , Mâle , Système de signalisation des MAP kinases , Obésité/métabolisme
2.
Bone Rep ; 22: 101794, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39139592

RÉSUMÉ

Background: Patients with bone metastases from solid tumors often have additional treatment with bone targeted agents (BTAs) to avoid symptomatic skeletal events (SSEs) such as clinically significant pathological fracture leading toradiation therapy or surgery to the bone, spinal cord compression, or hypercalcemia. The absolute value of BTA treatment in the era of immunotherapy (IO) is unknown. Methods: Patients with bone metastases treated with immunotherapy within the Alpine Tumor Immunology Registry were compared based on whether they received an additional BTA such as denosumab or zoledronic acid. The primary endpoint was time to first SSE. Continuous data were summarized as median and range, categorical data using frequency counts and percentages. Kaplan-Meier estimates were used to describe and visualize the effect of categorical variables. Results: One hundred and ninety-seven patients with bone metastases and treatment with immunotherapy such as nivolumab (48 %), pembrolizumab (40 %), atezolizumab (12 %), ipilimumab (9 %) and other immunotherapy (5 %) were included. The most frequent tumor types were lung cancer (50 %), malignant melanoma (11 %), renal cell cancer (10 %) and bladder cancer (9 %), respectively. One hundred and twenty-two patients (62 %) received a BTA treatment (91 % denosumab). The median treatment duration of a BTA was 178 days (min: 1 day, max: 2010 days). Out of the 197 patients, 47 (24 %) experienced at least one SSE, 100 (51 %) had bone pain. Ten of the 122 patients (8 %) receiving a BTA developed osteonecrosis of the jaw (ONJ). The percentage of patients without an SSE at fixed time points was higher if treated with a BTA (e.g., at 6 months, 92 % [95 % CI: 84 % - 96 %] versus 88 % [95 % CI: 77 % - 94 %]), but no significant difference in time to first SSE (HR 0.69; 95 % CI 0.34-1.39, log-rank p = 0.29) or time to first bone pain (HR: 0.85; 95 % CI: 0.51-1.43, p = 0.54) between these two groups could be detected. There were differences in OS between patients treated with a BTA and patients not treated with a BTA (HR: 1.46; 95 % CI: 1.01-2.10, p = 0.043). Conclusion: No significant difference in time to first SSE or bone pain was observed between patients who have received a BTA or not when treated with immunotherapy. Based on these retrospective results the indication of BTAs to reduce SSEs in cancer patients under treatment with immunotherapy needs further evaluation.

3.
Support Care Cancer ; 32(8): 554, 2024 Jul 27.
Article de Anglais | MEDLINE | ID: mdl-39066890

RÉSUMÉ

PURPOSE: Common side effects of taxane chemotherapy are nail toxicity and peripheral neuropathy (CIPN) causing severe impact on the quality of life. Different methods of cryotherapy to prevent these side effects have been tested. We investigated the use of machine-controlled cooling of hands and feet to reduce nail toxicity and CIPN in patients receiving taxane chemotherapy. METHODS: Patients receiving Docetaxel (planned dose ≥ 300 mg/m2) or Paclitaxel (planned dose ≥ 720 mg/m2 - ) in the adjuvant or palliative setting of different cancers were included. The dominant hand and foot were cooled to approximately 10 °C using the Hilotherapy machine. The contralateral hand and foot were used as intrapatient comparison. The primary endpoint was the occurrence of any CIPN due to paclitaxel or nail toxicity due to Docetaxel. Both the intention to treat population (ITT) and the per protocol population (PPP) were analyzed. RESULTS: A total of 69 patients, 21 treated with Docetaxel and 48 with Paclitaxel, were included at our centre between 08/2020 and 08/2022. Nail toxicity due to Docetaxel was overall not significantly improved by cooling in the ITT or PPP but a significant benefit across visits was found for the ITT. CIPN due to Paclitaxel was numerically better in the ITT and significantly better in the PPP. A significant benefit of cooling on CIPN occurrence across visits was found for the ITT and the PPP. Cooling was very well tolerated. CONCLUSION: Cooling of hands and feet has a clinically meaningful impact on reducing occurrence of CIPN and nail toxicity on treatment with taxanes. Effects are more significant over time and are dose dependent. TRIAL REGISTRATION NUMBER: 2020-00381. Date of registration. 24th February 2020.


Sujet(s)
Docetaxel , Onychopathies , Paclitaxel , Neuropathies périphériques , Humains , Femelle , Études prospectives , Adulte d'âge moyen , Mâle , Neuropathies périphériques/induit chimiquement , Neuropathies périphériques/prévention et contrôle , Sujet âgé , Docetaxel/administration et posologie , Docetaxel/effets indésirables , Paclitaxel/administration et posologie , Paclitaxel/effets indésirables , Onychopathies/thérapie , Onychopathies/induit chimiquement , Tumeurs/traitement médicamenteux , Adulte , Taxoïdes/effets indésirables , Taxoïdes/administration et posologie , Antinéoplasiques/effets indésirables , Antinéoplasiques/administration et posologie , Cryothérapie/méthodes , Qualité de vie
4.
EMBO Rep ; 25(6): 2635-2661, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38730210

RÉSUMÉ

Obesity is characterized by low-grade inflammation, energy imbalance and impaired thermogenesis. The role of regulatory T cells (Treg) in inflammation-mediated maladaptive thermogenesis is not well established. Here, we find that the p38 pathway is a key regulator of T cell-mediated adipose tissue (AT) inflammation and browning. Mice with T cells specifically lacking the p38 activators MKK3/6 are protected against diet-induced obesity, leading to an improved metabolic profile, increased browning, and enhanced thermogenesis. We identify IL-35 as a driver of adipocyte thermogenic program through the ATF2/UCP1/FGF21 pathway. IL-35 limits CD8+ T cell infiltration and inflammation in AT. Interestingly, we find that IL-35 levels are reduced in visceral fat from obese patients. Mechanistically, we demonstrate that p38 controls the expression of IL-35 in human and mouse Treg cells through mTOR pathway activation. Our findings highlight p38 signaling as a molecular orchestrator of AT T cell accumulation and function.


Sujet(s)
Interleukines , Obésité , Lymphocytes T régulateurs , Thermogenèse , p38 Mitogen-Activated Protein Kinases , Animaux , Interleukines/métabolisme , Obésité/métabolisme , Souris , Humains , p38 Mitogen-Activated Protein Kinases/métabolisme , Lymphocytes T régulateurs/immunologie , Lymphocytes T régulateurs/métabolisme , Sérine-thréonine kinases TOR/métabolisme , Transduction du signal , Lymphocytes T CD8+/immunologie , Lymphocytes T CD8+/métabolisme , Inflammation/métabolisme , Mâle , Souris de lignée C57BL , Souris knockout
5.
J Immunother ; 47(5): 190-194, 2024 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-38318726

RÉSUMÉ

Single nucleotide polymorphisms (SNPs) in the cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) gene, an inhibitor of T-cell priming, are associated with auto and alloimmunity. Studies implied a role for these SNPs as surrogate markers for immunotherapy-outcome in patients with melanoma. However, no predictive SNPs are defined to date. We analyzed different CTLA-4 SNPs in a large multicenter cohort of patients with ipilimumab-treated melanoma and investigated possible correlations with treatment-related outcomes. Archival blood and/or tumor tissue samples were collected from 361 patients with advanced-stage ipilimumab-treated (±nivolumab) in 6 Swiss and Dutch hospitals. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry based DNA genotyping was performed for 10 different CTLA-4 SNPs: 49A>G, CT60G>A, Jo27T>C, Jo30G>A, Jo31G>T, -658C>T, -1722T>C, -1661A>G, 318C>T, and C>T rs1863800. Associations between different allele genotypes and occurrence of grade ≥3 adverse events (AEs) and survival were tested using univariable logistic regressions or Cox proportional hazard models. 262/361 (73%) patients could be analyzed; 65% of those were males, the median age was 58 years, 39% showed a partial or complete response, and 65% had ≥1 AEs. A TT-genotype of -1722T>C SNP was significantly associated with a lower incidence of grade ≥3 AEs ( P = 0.049), whereas the GG-genotype of CT60G>A correlated with a higher incidence of grade ≥3 AEs ( P = 0.026). The TT-genotype of Jo27T>C SNP ( P = 0.056) and GG-genotype of Jo31G>T ( P = 0.046) were associated with overall survival. CTLA-4 SNPs might predict treatment-related outcomes in patients with melanoma receiving ipilimumab. Confirmatory studies are needed to fully exploit those findings as predictive biomarkers for ipilimumab AEs.


Sujet(s)
Antigène CTLA-4 , Ipilimumab , Mélanome , Stadification tumorale , Polymorphisme de nucléotide simple , Humains , Ipilimumab/effets indésirables , Ipilimumab/usage thérapeutique , Antigène CTLA-4/génétique , Mélanome/traitement médicamenteux , Mélanome/génétique , Mélanome/mortalité , Mâle , Femelle , Adulte d'âge moyen , Sujet âgé , Génotype , Adulte , Sujet âgé de 80 ans ou plus , Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Protocoles de polychimiothérapie antinéoplasique/effets indésirables , Résultat thérapeutique
6.
Sci Adv ; 10(3): eadk6524, 2024 Jan 19.
Article de Anglais | MEDLINE | ID: mdl-38241373

RÉSUMÉ

Pulmonary hypertension (PH) can affect both pulmonary arterial tree and cardiac function, often leading to right heart failure and death. Despite the urgency, the lack of understanding has limited the development of effective cardiac therapeutic strategies. Our research reveals that MCJ modulates mitochondrial response to chronic hypoxia. MCJ levels elevate under hypoxic conditions, as in lungs of patients affected by COPD, mice exposed to hypoxia, and myocardium from pigs subjected to right ventricular (RV) overload. The absence of MCJ preserves RV function, safeguarding against both cardiac and lung remodeling induced by chronic hypoxia. Cardiac-specific silencing is enough to protect against cardiac dysfunction despite the adverse pulmonary remodeling. Mechanistically, the absence of MCJ triggers a protective preconditioning state mediated by the ROS/mTOR/HIF-1α axis. As a result, it preserves RV systolic function following hypoxia exposure. These discoveries provide a potential avenue to alleviate chronic hypoxia-induced PH, highlighting MCJ as a promising target against this condition.


Sujet(s)
Hypertension pulmonaire , Animaux , Humains , Souris , Hypertension pulmonaire/étiologie , Hypertension pulmonaire/traitement médicamenteux , Hypoxie , Poumon , Myocarde , Artère pulmonaire , Suidae
7.
Proc Natl Acad Sci U S A ; 121(3): e2300096121, 2024 Jan 16.
Article de Anglais | MEDLINE | ID: mdl-38194457

RÉSUMÉ

The prevalence of overweight and obesity continues to rise in the population worldwide. Because it is an important predisposing factor for cancer, cardiovascular diseases, diabetes mellitus, and COVID-19, obesity reduces life expectancy. Adipose tissue (AT), the main fat storage organ with endocrine capacity, plays fundamental roles in systemic metabolism and obesity-related diseases. Dysfunctional AT can induce excess or reduced body fat (lipodystrophy). Dido1 is a marker gene for stemness; gene-targeting experiments compromised several functions ranging from cell division to embryonic stem cell differentiation, both in vivo and in vitro. We report that mutant mice lacking the DIDO N terminus show a lean phenotype. This consists of reduced AT and hypolipidemia, even when mice are fed a high-nutrient diet. DIDO mutation caused hypothermia due to lipoatrophy of white adipose tissue (WAT) and dermal fat thinning. Deep sequencing of the epididymal white fat (Epi WAT) transcriptome supported Dido1 control of the cellular lipid metabolic process. We found that, by controlling the expression of transcription factors such as C/EBPα or PPARγ, Dido1 is necessary for adipocyte differentiation, and that restoring their expression reestablished adipogenesis capacity in Dido1 mutants. Our model differs from other lipodystrophic mice and could constitute a new system for the development of therapeutic intervention in obesity.


Sujet(s)
Adipogenèse , Lipodystrophie , Animaux , Souris , Adipogenèse/génétique , Différenciation cellulaire , Régime alimentaire , Obésité/génétique , Surpoids
8.
Hepatology ; 77(3): 874-887, 2023 03 01.
Article de Anglais | MEDLINE | ID: mdl-35592906

RÉSUMÉ

Obesity features excessive fat accumulation in several body tissues and induces a state of chronic low-grade inflammation that contributes to the development of diabetes, steatosis, and insulin resistance. Recent research has shown that this chronic inflammation is crucially dependent on p38 pathway activity in macrophages, suggesting p38 inhibition as a possible treatment for obesity comorbidities. Nevertheless, we report here that lack of p38 activation in myeloid cells worsens high-fat diet-induced obesity, diabetes, and steatosis. Deficient p38 activation increases macrophage IL-12 production, leading to inhibition of hepatic FGF21 and reduction of thermogenesis in the brown fat. The implication of FGF21 in the phenotype was confirmed by its specific deletion in hepatocytes. We also found that IL-12 correlates with liver damage in human biopsies, indicating the translational potential of our results. Our findings suggest that myeloid p38 has a dual role in inflammation and that drugs targeting IL-12 might improve the homeostatic regulation of energy balance in response to metabolic stress.


Sujet(s)
Stéatose hépatique , Insulinorésistance , Humains , Animaux , Souris , Interleukine-12 , Obésité/métabolisme , Stéatose hépatique/métabolisme , Tissu adipeux brun/métabolisme , Métabolisme énergétique , Inflammation/métabolisme , Alimentation riche en graisse , Macrophages/métabolisme , Thermogenèse , Souris de lignée C57BL
9.
Article de Anglais | LILACS-Express | LILACS | ID: biblio-1534156

RÉSUMÉ

Introduction: Buerger's disease (BD) generally affects men, young people, and smokers, but it can also affect women. Its incidence is rare in Latin America. Case report: A 40-year-old Colombian woman, active smoker and user of psychoactive substances, attended the emergency department of a tertiary care center due to symptoms of 3 days consisting of retraction of the corner of the mouth, drooling, and involuntary tongue movements. The patient, who had a history of uncontrolled diabetes and recent acute ischemia of the right upper limb due to acute thrombosis, required surgical management and subsequent use of oral anticoagulation. She later developed necrotic changes in the distal phalanges of the right hand that required ablative therapy. Since age, sex and limb involvement were not typical for BD, collagenosis, vasculitis or thrombophilia were ruled out, but after excluding these disorders, BD with atypical features was considered. The patient was discharged with oral anticoagulation, aspirin, combined analgesia, physiotherapy, and recommendation for smoking cessation. Conclusions: Age, sex, smoking and comorbidities such as diabetes are risk factors for BD. Imaging and histopathology are the gold standard for the definitive diagnosis of this entity. Multidisciplinary management, lifestyle changes, smoking cessation, pain control, good wound healing and social support are key aspects for better clinical outcomes in patients with BD.


Introducción. La enfermedad de Buerger (EB) afecta generalmente a hombres, jóvenes y fumadores, y aunque también puede afectar a mujeres, su incidencia es rara en Latinoamérica. Presentación del caso. Mujer colombiana de 40 años, fumadora activa y consumidora de sustancias psicoactivas, quien acudió al servicio de urgencias de una institución de tercer nivel por síntomas de 3 días de evolución consistentes en retracción de la comisura bucal, babeo y movimientos involuntarios de la lengua. La paciente, que tenía antecedente de diabetes no controlada y reciente isquemia aguda de miembro superior derecho por trombosis aguda, requirió manejo intervencionista y subsecuente uso de anticoagulación oral. Posteriormente, desarrolló cambios necróticos en falanges distales de mano derecha y requirió terapia ablativa. Dado que la edad, el género y la afectación de las extremidades no eran típicos para EB, se procedió a descartar colagenosis, vasculitis o trombofilia, pero tras excluir estas patologías se consideró EB con características atípicas. La paciente fue dada de alta con anticoagulación oral, aspirina, analgesia combinada, fisioterapia y recomendación de suspender el consumo de tabaco. Conclusiones. La edad, el género, el tabaquismo y las comorbilidades como diabetes son factores de riesgo para EB. La imagenología e histopatología son estándar de oro en el diagnóstico definitivo de esta entidad. El manejo multidisciplinario, los cambios en el estilo de vida, la cesación del tabaquismo, el control del dolor, la buena cicatrización de heridas y el apoyo social son aspectos importantes para obtener mejores resultados clínicos en pacientes con EB.

10.
Elife ; 112022 08 16.
Article de Anglais | MEDLINE | ID: mdl-35971771

RÉSUMÉ

Stress-activated p38 kinases control a plethora of functions, and their dysregulation has been linked to the development of steatosis, obesity, immune disorders, and cancer. Therefore, they have been identified as potential targets for novel therapeutic strategies. There are four p38 family members (p38α, p38ß, p38γ, and p38δ) that are activated by MKK3 and MKK6. Here, we demonstrate that lack of MKK6 reduces the lifespan in mice. Longitudinal study of cardiac function in MKK6 KO mice showed that young mice develop cardiac hypertrophy which progresses to cardiac dilatation and fibrosis with age. Mechanistically, lack of MKK6 blunts p38α activation while causing MKK3-p38γ/δ hyperphosphorylation and increased mammalian target of rapamycin (mTOR) signaling, resulting in cardiac hypertrophy. Cardiac hypertrophy in MKK6 KO mice is reverted by knocking out either p38γ or p38δ or by inhibiting the mTOR pathway with rapamycin. In conclusion, we have identified a key role for the MKK3/6-p38γ/δ pathway in the development of cardiac hypertrophy, which has important implications for the clinical use of p38α inhibitors in the long-term treatment since they might result in cardiotoxicity.


The human heart can increase its size to supply more blood to the body's organs. This process, called hypertrophy, can happen during exercise or be caused by medical conditions, such as high blood pressure or inherited genetic diseases. If hypertrophy is continually driven by illness, this can cause the heart to fail and no longer be able to properly pump blood around the body. For hypertrophy to happen, several molecular changes occur in the cells responsible for contracting the heart, including activation of the p38 pathway. Within this pathway is a p38 enzyme as well as a series of other proteins which are sequentially turned on in response to stress, such as inflammatory molecules or mechanical forces that alter the cell's shape. There are different types of p38 enzyme which have been linked to other diseases, making them a promising target for drug development. However, clinical trials blocking individual members of the p38 family have had disappointing results. An alternative approach is to target other proteins involved in the p38 pathway, such as MKK6, but it is not known what effect this might have. To investigate, Romero-Becerra et al. genetically modified mice to not have any MKK6 protein. As a result, these mice had a shorter lifespan, with hypertrophy developing at a young age that led to heart problems. Romero-Becerra et al. used different mice models to understand why this happened, showing that a lack of MKK6 reduces the activity of a specific member of the p38 family called p38α. However, this blockage boosted a different branch of the pathway which involved two other p38 proteins, p38γ and p38δ. This, in turn, triggered another key pathway called mTOR which also promotes hypertrophy of the heart. These results suggest that drugs blocking MKK6 and p38α could lead to side effects that cause further harm to the heart. A more promising approach for treating hypertrophic heart conditions could be to inhibit p38γ and/or p38δ. However, before this can be fully explored, further work is needed to generate compounds that specifically target these proteins.


Sujet(s)
Cardiopathies , MAP Kinase Kinase 6 , Mitogen-Activated Protein Kinase 13 , Animaux , Cardiomégalie , Cardiopathies/génétique , Cardiopathies/anatomopathologie , Études longitudinales , MAP Kinase Kinase 3/métabolisme , MAP Kinase Kinase 6/génétique , Souris , Mitogen-Activated Protein Kinase 13/métabolisme , Sérine-thréonine kinases TOR/métabolisme , p38 Mitogen-Activated Protein Kinases/métabolisme
11.
Nat Commun ; 13(1): 1096, 2022 03 01.
Article de Anglais | MEDLINE | ID: mdl-35232994

RÉSUMÉ

Altered methionine metabolism is associated with weight gain in obesity. The methionine adenosyltransferase (MAT), catalyzing the first reaction of the methionine cycle, plays an important role regulating lipid metabolism. However, its role in obesity, when a plethora of metabolic diseases occurs, is still unknown. By using antisense oligonucleotides (ASO) and genetic depletion of Mat1a, here, we demonstrate that Mat1a deficiency in diet-induce obese or genetically obese mice prevented and reversed obesity and obesity-associated insulin resistance and hepatosteatosis by increasing energy expenditure in a hepatocyte FGF21 dependent fashion. The increased NRF2-mediated FGF21 secretion induced by targeting Mat1a, mobilized plasma lipids towards the BAT to be catabolized, induced thermogenesis and reduced body weight, inhibiting hepatic de novo lipogenesis. The beneficial effects of Mat1a ASO were abolished following FGF21 depletion in hepatocytes. Thus, targeting Mat1a activates the liver-BAT axis by increasing NRF2-mediated FGF21 secretion, which prevents obesity, insulin resistance and hepatosteatosis.


Sujet(s)
Tissu adipeux brun , Insulinorésistance , Methionine adenosyltransferase , Obésité , Oligonucléotides antisens , Tissu adipeux brun/métabolisme , Animaux , Métabolisme énergétique , Foie/métabolisme , Methionine adenosyltransferase/génétique , Methionine adenosyltransferase/métabolisme , Souris , Facteur-2 apparenté à NF-E2/génétique , Facteur-2 apparenté à NF-E2/métabolisme , Obésité/génétique , Obésité/métabolisme , Obésité/prévention et contrôle , Oligonucléotides antisens/métabolisme , Oligonucléotides antisens/pharmacologie
12.
Science ; 375(6586): 1275-1281, 2022 03 18.
Article de Anglais | MEDLINE | ID: mdl-35298255

RÉSUMÉ

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale.


Sujet(s)
Adaptation physiologique , Évolution biologique , Écosystème , Trifolium/physiologie , Urbanisation , Villes , Gènes de plante , Génome végétal , Acide cyanhydrique/métabolisme , Population rurale , Trifolium/génétique
13.
PLoS Biol ; 19(11): e3001447, 2021 11.
Article de Anglais | MEDLINE | ID: mdl-34758018

RÉSUMÉ

During the first weeks of postnatal heart development, cardiomyocytes undergo a major adaptive metabolic shift from glycolytic energy production to fatty acid oxidation. This metabolic change is contemporaneous to the up-regulation and activation of the p38γ and p38δ stress-activated protein kinases in the heart. We demonstrate that p38γ/δ contribute to the early postnatal cardiac metabolic switch through inhibitory phosphorylation of glycogen synthase 1 (GYS1) and glycogen metabolism inactivation. Premature induction of p38γ/δ activation in cardiomyocytes of newborn mice results in an early GYS1 phosphorylation and inhibition of cardiac glycogen production, triggering an early metabolic shift that induces a deficit in cardiomyocyte fuel supply, leading to whole-body metabolic deregulation and maladaptive cardiac pathogenesis. Notably, the adverse effects of forced premature cardiac p38γ/δ activation in neonate mice are prevented by maternal diet supplementation of fatty acids during pregnancy and lactation. These results suggest that diet interventions have a potential for treating human cardiac genetic diseases that affect heart metabolism.


Sujet(s)
Glycogen synthase/métabolisme , Mitogen-Activated Protein Kinase 12/métabolisme , Mitogen-Activated Protein Kinase 13/métabolisme , Myocarde/enzymologie , Animaux , Animaux nouveau-nés , Cardiomégalie/enzymologie , Cardiomégalie/anatomopathologie , Cardiomégalie/physiopathologie , Alimentation riche en graisse , Activation enzymatique , Comportement alimentaire , Femelle , Délétion de gène , Intolérance au glucose/enzymologie , Glycogène/métabolisme , Glycogen Synthase Kinase 3/métabolisme , Insulinorésistance , Métabolisme lipidique , Système de signalisation des MAP kinases , Souris de lignée C57BL , Myocytes cardiaques/enzymologie , Spécificité d'organe , Phosphorylation
14.
Immunity ; 54(11): 2578-2594.e5, 2021 11 09.
Article de Anglais | MEDLINE | ID: mdl-34717795

RÉSUMÉ

Peritoneal immune cells reside unanchored within the peritoneal fluid in homeostasis. Here, we examined the mechanisms that control bacterial infection in the peritoneum using a mouse model of abdominal sepsis following intraperitoneal Escherichia coli infection. Whole-mount immunofluorescence and confocal microscopy of the peritoneal wall and omentum revealed that large peritoneal macrophages (LPMs) rapidly cleared bacteria and adhered to the mesothelium, forming multilayered cellular aggregates composed by sequentially recruited LPMs, B1 cells, neutrophils, and monocyte-derived cells (moCs). The formation of resident macrophage aggregates (resMφ-aggregates) required LPMs and thrombin-dependent fibrin polymerization. E. coli infection triggered LPM pyroptosis and release of inflammatory mediators. Resolution of these potentially inflammatory aggregates required LPM-mediated recruitment of moCs, which were essential for fibrinolysis-mediated resMφ-aggregate disaggregation and the prevention of peritoneal overt inflammation. Thus, resMφ-aggregates provide a physical scaffold that enables the efficient control of peritoneal infection, with implications for antimicrobial immunity in other body cavities, such as the pleural cavity or brain ventricles.


Sujet(s)
Infections bactériennes/étiologie , Infections bactériennes/métabolisme , Interactions hôte-pathogène/immunologie , Macrophages péritonéaux/immunologie , Macrophages péritonéaux/métabolisme , Cavité péritonéale/microbiologie , Animaux , Marqueurs biologiques , Microenvironnement cellulaire/immunologie , Modèles animaux de maladie humaine , Prédisposition aux maladies/immunologie , Médiateurs de l'inflammation/métabolisme , Souris , Péritonite/étiologie , Péritonite/métabolisme , Péritonite/anatomopathologie
15.
Mol Metab ; 50: 101190, 2021 08.
Article de Anglais | MEDLINE | ID: mdl-33588102

RÉSUMÉ

Non-alcoholic fatty liver disease (NAFLD) is an important component of metabolic syndrome and one of the most prevalent liver diseases worldwide. This disorder is closely linked to hepatic insulin resistance, lipotoxicity, and inflammation. Although the mechanisms that cause steatosis and chronic liver injury in NAFLD remain unclear, a key component of this process is the activation of stress-activated kinases (SAPKs), including p38 and JNK in the liver and immune system. This review summarizes findings which indicate that the dysregulation of stress kinases plays a fundamental role in the development of steatosis and are important players in inducing liver fibrosis. To avoid the development of steatohepatitis and liver cancer, SAPK activity must be tightly regulated not only in the hepatocytes but also in other tissues, including cells of the immune system. Possible cellular mechanisms of SAPK actions are discussed.


Sujet(s)
Carcinome hépatocellulaire/métabolisme , Tumeurs du foie/métabolisme , Foie/anatomopathologie , Système de signalisation des MAP kinases , Stéatose hépatique non alcoolique/métabolisme , Animaux , Autophagie/effets des médicaments et des substances chimiques , Carcinome hépatocellulaire/traitement médicamenteux , Carcinome hépatocellulaire/anatomopathologie , Modèles animaux de maladie humaine , Humains , Insulinorésistance , JNK Mitogen-Activated Protein Kinases/métabolisme , Tumeurs du foie/traitement médicamenteux , Tumeurs du foie/anatomopathologie , Stéatose hépatique non alcoolique/traitement médicamenteux , Stéatose hépatique non alcoolique/anatomopathologie , Agents protecteurs/pharmacologie , Agents protecteurs/usage thérapeutique , p38 Mitogen-Activated Protein Kinases/métabolisme
16.
Elife ; 92020 12 08.
Article de Anglais | MEDLINE | ID: mdl-33287957

RÉSUMÉ

Liver metabolism follows diurnal fluctuations through the modulation of molecular clock genes. Disruption of this molecular clock can result in metabolic disease but its potential regulation by immune cells remains unexplored. Here, we demonstrated that in steady state, neutrophils infiltrated the mouse liver following a circadian pattern and regulated hepatocyte clock-genes by neutrophil elastase (NE) secretion. NE signals through c-Jun NH2-terminal kinase (JNK) inhibiting fibroblast growth factor 21 (FGF21) and activating Bmal1 expression in the hepatocyte. Interestingly, mice with neutropenia, defective neutrophil infiltration or lacking elastase were protected against steatosis correlating with lower JNK activation, reduced Bmal1 and increased FGF21 expression, together with decreased lipogenesis in the liver. Lastly, using a cohort of human samples we found a direct correlation between JNK activation, NE levels and Bmal1 expression in the liver. This study demonstrates that neutrophils contribute to the maintenance of daily hepatic homeostasis through the regulation of the NE/JNK/Bmal1 axis.


Every day, the body's biological processes work to an internal clock known as the circadian rhythm. This rhythm is controlled by 'clock genes' that are switched on or off by daily physical and environmental cues, such as changes in light levels. These daily rhythms are very finely tuned, and disturbances can lead to serious health problems, such as diabetes or high blood pressure. The ability of the body to cycle through the circadian rhythm each day is heavily influenced by the clock of one key organ: the liver. This organ plays a critical role in converting food and drink into energy. There is evidence that neutrophils ­ white blood cells that protect the body by being the first response to inflammation ­ can influence how the liver performs its role in obese people, by for example, releasing a protein called elastase. Additionally, the levels of neutrophils circulating in the blood change following a daily pattern. Crespo, González-Terán et al. wondered whether neutrophils enter the liver at specific times of the day to control liver's daily rhythm. Crespo, González-Terán et al. revealed that neutrophils visit the liver in a pattern that peaks when it gets light and dips when it gets dark by counting the number of neutrophils in the livers of mice at different times of the day. During these visits, neutrophils secreted elastase, which activated a protein called JNK in the cells of the mice's liver. This subsequently blocked the activity of another protein, FGF21, which led to the activation of the genes that allow cells to make fat molecules for storage. JNK activation also switched on the clock gene, Bmal1, ultimately causing fat to build up in the mice's liver. Crespo, González-Terán et al. also found that, in samples from human livers, the levels of elastase, the activity of JNK, and whether the Bmal1 gene was switched on were tightly linked. This suggests that neutrophils may be controlling the liver's rhythm in humans the same way they do in mice. Overall, this research shows that neutrophils can control and reset the liver's daily rhythm using a precisely co-ordinated series of molecular changes. These insights into the liver's molecular clock suggest that elastase, JNK and BmaI1 may represent new therapeutic targets for drugs or smart medicines to treat metabolic diseases such as diabetes or high blood pressure.


Sujet(s)
Protéines CLOCK/métabolisme , Régulation de l'expression des gènes/physiologie , Hépatocytes/métabolisme , Granulocytes neutrophiles/physiologie , Animaux , Protéines CLOCK/génétique , Cellules cultivées , Rythme circadien , Facteurs de croissance fibroblastique/génétique , Facteurs de croissance fibroblastique/métabolisme , Humains , Inflammation/métabolisme , MAP Kinase Kinase 4/génétique , MAP Kinase Kinase 4/métabolisme , Souris , Souris transgéniques , Neutropénie
17.
Rev. colomb. reumatol ; 27(supl.2): 125-139, oct.-dic. 2020. tab, graf
Article de Espagnol | LILACS | ID: biblio-1341347

RÉSUMÉ

RESUMEN El síndrome de Sjögren primario (SSp) es una enfermedad autoinmune que afecta principalmente al tejido glandular. A pesar de ello, puede involucrar otros sistemas, siendo el compromiso neuropsiquiátrico una manifestación extraglandular común. Su presentación clínica varía ampliamente según el dominio que se encuentre afectado, y por tanto puede dividirse en tres grandes categorías: sistema nervioso central, sistema nervioso periférico y psiquiátrico. Algunas de estas complicaciones comparten mecanismos fisiopatológicos comunes, entre los principales la vasculitis/vasculopatía, la infiltración linfocítica y la presencia de anticuerpos antineuronales. La diversidad en la presentación clínica de esta entidad impide hacer una aproximación diagnóstica común, por lo cual la utilización de estudios específicos depende de un adecuado reconocimiento y de la localización por parte del clínico. El tratamiento debe dirigirse al mecanismo fisiopatológico implicado y, de acuerdo con el tipo de manifestación, puede incluso estar limitado al manejo sintomático.


ABSTRACT Primary Sjögren's syndrome is an autoimmune disease that mainly involves glandular tissue. Despite this, it can potentially develop systemic involvement, within which neuropsychiatric manifestations are common. The clinical presentation may vary widely depending on the domain affected, and may thus be classified into three categories: central nervous system, peripheral nervous system, and psychiatric. Some of these complications share a common pathophysiology, amongst which are vasculitis/ vasculopathy, lymphocytic infiltration and positive antineuronal antibodies. The wide clinical presentation makes it difficult to establish a common diagnostic approach, making it essential for the clinician to recognise and localise the type of compromise, so that diagnostic tools can be more advantageously employed. Treatment must be directed towards the underlying pathophysiology, and depending on the type of compromise, it can even be limited solely to the management of symptoms.


Sujet(s)
Humains , Syndrome de Gougerot-Sjögren , Neuropsychiatrie , Qualité de vie , Maladies auto-immunes , Thérapeutique , Diagnostic , Neurologie
18.
Rev. colomb. reumatol ; 27(3): 205-209, jul.-set. 2020. graf
Article de Espagnol | LILACS | ID: biblio-1251659

RÉSUMÉ

RESUMEN La crisis renal esclerodérmica (CRS) es una manifestación rara de la esclerosis sistémica (ES). Se presenta como hipertensión arterial de nuevo inicio, empeoramiento o aceleración de la hipertensión arterial crónica o rápido deterioro de la función renal, frecuentemente acompañada de signos de hemolisis microangiopática. Su relación con el síndrome hemo lítico urémico es infrecuente, existiendo tan solo un caso similar reportado en la literatura. Presentamos el caso de una mujer de 36 arios en tratamiento para ES con cefalea global, pulsátil e intensa, convulsión tónico-clónica, cifras de presión arterial altas, falla renal aguda y hemólisis no autoinmune persistente. La evaluación de ADAMTS13 mostró un 60,6% de actividad. El estudio genético para búsqueda de mutaciones predisponentes para sín drome hemolítico urémico atípico (SHUa) reveló variante homocigota en el gen ADAMTS13, c.3287G>A (p.Arg1096His). Se inició tratamiento con eculizumab, observándose en poco tiempo mejoría de la hemólisis, función renal y estado clínico, con algunos efectos benéficos notorios e inesperados sobre la ES.


ABSTRACT Scleroderma renal crisis (SRC) is a rare manifestation of systemic sclerosis (SSc), presented as hypertension of new onset, worsening and / or acceleration of chronic hypertension, or rapid deterioration of renal function, often accompanied by signs of microangiopathic haemolysis. It is rarely associated with haemolytic uraemic syndrome, and there is only one similar case reported in the literature. The case is presented here of a 36-year-old woman on treatment for SSc with global, pulsatile and intense headache, clonic tonic convulsions, high blood pressure levels, acute renal failure, and persistent non-autoimmune haemoly sis. The evaluation of ADAMTS13 showed 60.6% of activity. The genetic study to search for mutations predisposing to atypical haemolytic uraemic syndrome (aHUS) revealed a homozygous variant in ADAMTS13 gene, c.3287G>A (p.Arg1096His). Eculizumab was star ted, with an improvement being observed in a short time in the haemolysis, renal function, and clinical status, with some notable and unexpected beneficial effects on SSc.


Sujet(s)
Humains , Femelle , Adulte , Thérapeutique , Syndrome hémolytique et urémique , Rein , Sclérodermie systémique , Signes et symptômes , Anticorps monoclonaux
19.
Sci Adv ; 6(31): eaba5345, 2020 07.
Article de Anglais | MEDLINE | ID: mdl-32832682

RÉSUMÉ

Heteroplasmy, multiple variants of mitochondrial DNA (mtDNA) in the same cytoplasm, may be naturally generated by mutations but is counteracted by a genetic mtDNA bottleneck during oocyte development. Engineered heteroplasmic mice with nonpathological mtDNA variants reveal a nonrandom tissue-specific mtDNA segregation pattern, with few tissues that do not show segregation. The driving force for this dynamic complex pattern has remained unexplained for decades, challenging our understanding of this fundamental biological problem and hindering clinical planning for inherited diseases. Here, we demonstrate that the nonrandom mtDNA segregation is an intracellular process based on organelle selection. This cell type-specific decision arises jointly from the impact of mtDNA haplotypes on the oxidative phosphorylation (OXPHOS) system and the cell metabolic requirements and is strongly sensitive to the nuclear context and to environmental cues.

20.
Proc Natl Acad Sci U S A ; 117(28): 16492-16499, 2020 07 14.
Article de Anglais | MEDLINE | ID: mdl-32601222

RÉSUMÉ

Metabolic stress causes activation of the cJun NH2-terminal kinase (JNK) signal transduction pathway. It is established that one consequence of JNK activation is the development of insulin resistance and hepatic steatosis through inhibition of the transcription factor PPARα. Indeed, JNK1/2 deficiency in hepatocytes protects against the development of steatosis, suggesting that JNK inhibition represents a possible treatment for this disease. However, the long-term consequences of JNK inhibition have not been evaluated. Here we demonstrate that hepatic JNK controls bile acid production. We found that hepatic JNK deficiency alters cholesterol metabolism and bile acid synthesis, conjugation, and transport, resulting in cholestasis, increased cholangiocyte proliferation, and intrahepatic cholangiocarcinoma. Gene ablation studies confirmed that PPARα mediated these effects of JNK in hepatocytes. This analysis highlights potential consequences of long-term use of JNK inhibitors for the treatment of metabolic syndrome.


Sujet(s)
Acides et sels biliaires/métabolisme , Cholangiocarcinome/enzymologie , Mitogen-Activated Protein Kinase 8/métabolisme , Mitogen-Activated Protein Kinase 9/métabolisme , Animaux , Cholangiocarcinome/génétique , Cholangiocarcinome/métabolisme , Cholangiocarcinome/physiopathologie , Homéostasie , Humains , Mâle , Souris , Souris de lignée C57BL , Souris knockout , Mitogen-Activated Protein Kinase 8/génétique , Mitogen-Activated Protein Kinase 9/génétique , Récepteur PPAR alpha/génétique , Récepteur PPAR alpha/métabolisme
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