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1.
Sci Adv ; 10(28): eadi4746, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38996023

RESUMEN

Oxysterols are metabolites of cholesterol that regulate cholesterol homeostasis. Among these, the most abundant oxysterol is 27-hydroxycholesterol (27HC), which can cross the blood-brain barrier. Because 27HC functions as an endogenous selective estrogen receptor modulator, we hypothesize that 27HC binds to the estrogen receptor α (ERα) in the brain to regulate energy balance. Supporting this view, we found that delivering 27HC to the brain reduced food intake and activated proopiomelanocortin (POMC) neurons in the arcuate nucleus of the hypothalamus (POMCARH) in an ERα-dependent manner. In addition, we observed that inhibiting brain ERα, deleting ERα in POMC neurons, or chemogenetic inhibition of POMCARH neurons blocked the anorexigenic effects of 27HC. Mechanistically, we further revealed that 27HC stimulates POMCARH neurons by inhibiting the small conductance of the calcium-activated potassium (SK) channel. Together, our findings suggest that 27HC, through its interaction with ERα and modulation of the SK channel, inhibits food intake as a negative feedback mechanism against a surge in circulating cholesterol.


Asunto(s)
Núcleo Arqueado del Hipotálamo , Receptor alfa de Estrógeno , Conducta Alimentaria , Hidroxicolesteroles , Neuronas , Proopiomelanocortina , Núcleo Arqueado del Hipotálamo/metabolismo , Núcleo Arqueado del Hipotálamo/efectos de los fármacos , Animales , Hidroxicolesteroles/farmacología , Hidroxicolesteroles/metabolismo , Receptor alfa de Estrógeno/metabolismo , Neuronas/metabolismo , Neuronas/efectos de los fármacos , Proopiomelanocortina/metabolismo , Ratones , Femenino
2.
Phytomedicine ; 131: 155776, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38851104

RESUMEN

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a challenging disease to interfere with and represents a potential long-term risk factor for hepatic fibrosis and liver cancer. The Xiezhuo Tiaozhi (XZTZ) formula, a water extract from crude herbs, has been widely used as an anti-NAFLD agent through clinical observation. However, the underlying pharmacological mechanisms of the XZTZ formula and its impact on the potential pathways against NAFLD have not been elucidated. PURPOSE: Our study aims to investigate the pharmacological effects and underlying regulatory mechanisms of the XZTZ formula to treat NAFLD. METHODS: The possible active components and pharmacological mechanisms of the XZTZ formula against NAFLD were identified using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) and molecular docking. To further explore the potential mechanisms, forty-eight 6-week-old male C57BL/6 J mice were given individual attention with high-fat and high-sugar diet (HFHSD) or relevant control (Ctrl) diets for 16 weeks to successfully construct a NAFLD mouse model. Subsequently, the levels of serum biochemicals, pathological changes in the liver, and pyroptosis levels were assessed in mice to investigate the therapeutic effects of the XZTZ formula. Further, LPS-induced RAW264.7 cells and Immortalized Mouse Kupffer cells (ImKC) were used to verify the potential mechanisms of the XZTZ formula against NAFLD in vitro. RESULTS: We identified 7 chemical compounds and 2 potential therapeutic targets as plausible therapeutic points for the treatment of NAFLD using the XZTZ formula. Subsequent histopathological analysis revealed marked hepatic steatosis and lipid accumulation in the HFHSD mice liver, while conditions were effectively ameliorated by administration of the XZTZ formula. Additionally, our work demonstrated that the XZTZ formula could attenuate M1 polarization, promote M2 polarization, and suppress pyroptosis via the SIRT1 pathway in tissue samples. Moreover, validation performed through LPS-induced RAW264.7 and ImKC cells by showing that silencing SIRT1 weaken the effects of the XZTZ formula on relative pyroptosis affirmed that its role was associated with the SIRT1 pathway in macrophage. CONCLUSION: These findings suggest that the XZTZ formula alleviated hepatic steatosis and lipid accumulation in NAFLD mice. These ameliorations are associated with mechanisms involving the attenuation of M1 polarization, promotion of M2 polarization, and anti-pyroptosis effects through the SIRT1 pathway.


Asunto(s)
Medicamentos Herbarios Chinos , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico , Piroptosis , Sirtuina 1 , Animales , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Sirtuina 1/metabolismo , Masculino , Ratones , Piroptosis/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Células RAW 264.7 , Macrófagos/efectos de los fármacos , Modelos Animales de Enfermedad , Dieta Alta en Grasa/efectos adversos , Simulación del Acoplamiento Molecular , Hígado/efectos de los fármacos
3.
Sci Adv ; 10(26): eadn5229, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38924414

RESUMEN

There is a regional preference around lymph nodes (LNs) for adipose beiging. Here, we show that local LN removal within inguinal white adipose tissue (iWAT) greatly impairs cold-induced beiging, and this impairment can be restored by injecting M2 macrophages or macrophage-derived C-C motif chemokine (CCL22) into iWAT. CCL22 injection into iWAT effectively promotes iWAT beiging, while blocking CCL22 with antibodies can prevent it. Mechanistically, the CCL22 receptor, C-C motif chemokine receptor 4 (CCR4), within eosinophils and its downstream focal adhesion kinase/p65/interleukin-4 signaling are essential for CCL22-mediated beige adipocyte formation. Moreover, CCL22 levels are inversely correlated with body weight and fat mass in mice and humans. Acute elevation of CCL22 levels effectively prevents diet-induced body weight and fat gain by enhancing adipose beiging. Together, our data identify the CCL22-CCR4 axis as an essential mediator for LN-controlled adaptive thermogenesis and highlight its potential to combat obesity and its associated complications.


Asunto(s)
Tejido Adiposo Blanco , Quimiocina CCL22 , Metabolismo Energético , Ganglios Linfáticos , Macrófagos , Termogénesis , Animales , Femenino , Humanos , Masculino , Ratones , Adipocitos Beige/metabolismo , Tejido Adiposo Blanco/metabolismo , Quimiocina CCL22/metabolismo , Eosinófilos/metabolismo , Ganglios Linfáticos/metabolismo , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Obesidad/metabolismo , Receptores CCR4/metabolismo , Transducción de Señal
4.
Nat Aging ; 4(6): 839-853, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38858606

RESUMEN

Thermogenic beige adipocytes are recognized as potential therapeutic targets for combating metabolic diseases. However, the metabolic advantages that they offer are compromised with aging. Here we show that treating mice with estrogen (E2), a hormone that decreases with age, can counteract the age-related decline in beige adipogenesis when exposed to cold temperature while concurrently enhancing energy expenditure and improving glucose tolerance in mice. Mechanistically, we found that nicotinamide phosphoribosyl transferase (NAMPT) plays a pivotal role in facilitating the formation of E2-induced beige adipocytes, which subsequently suppresses the onset of age-related endoplasmic reticulum (ER) stress. Furthermore, we found that targeting NAMPT signaling, either genetically or pharmacologically, can restore the formation of beige adipocytes by increasing the number of perivascular adipocyte progenitor cells. Conversely, the absence of NAMPT signaling prevents this process. Together, our findings shed light on the mechanisms regulating the age-dependent impairment of beige adipocyte formation and underscore the E2-NAMPT-controlled ER stress pathway as a key regulator of this process.


Asunto(s)
Adipocitos Beige , Adipogénesis , Envejecimiento , Estrés del Retículo Endoplásmico , Estrógenos , Nicotinamida Fosforribosiltransferasa , Nicotinamida Fosforribosiltransferasa/metabolismo , Animales , Adipogénesis/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Ratones , Envejecimiento/efectos de los fármacos , Envejecimiento/fisiología , Estrógenos/metabolismo , Estrógenos/farmacología , Adipocitos Beige/efectos de los fármacos , Adipocitos Beige/metabolismo , Citocinas/metabolismo , Transducción de Señal/efectos de los fármacos , Femenino , Ratones Endogámicos C57BL , Metabolismo Energético/efectos de los fármacos
5.
Molecules ; 29(11)2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38893567

RESUMEN

Curcumin (Cur) is a phytochemical with various beneficial properties, including antioxidant, anti-inflammatory, and anticancer activities. However, its hydrophobicity, poor bioavailability, and stability limit its application in many biological approaches. In this study, a novel amphiphilic chitosan wall material was synthesized. The process was carried out via grafting chitosan with succinic anhydride (SA) as a hydrophilic group and deoxycholic acid (DA) as a hydrophobic group; 1H-NMR, FTIR, and XRD were employed to characterize the amphiphilic chitosan (CS-SA-DA). Using a low-cost, inorganic solvent-based procedure, CS-SA-DA was self-assembled to load Cur nanomicelles. This amphiphilic polymer formed self-assembled micelles with a core-shell structure and a critical micelle concentration (CMC) of 0.093 mg·mL-1. Cur-loaded nanomicelles were prepared by self-assembly and characterized by the Nano Particle Size Potential Analyzer and transmission electron microscopy (TEM). The mean particle size of the spherical Cur-loaded micelles was 770 nm. The drug entrapment efficiency and loading capacities were up to 80.80 ± 0.99% and 19.02 ± 0.46%, respectively. The in vitro release profiles of curcumin from micelles showed a constant release of the active drug molecule. Cytotoxicity studies and toxicity tests for zebrafish exhibited the comparable efficacy and safety of this delivery system. Moreover, the results showed that the entrapment of curcumin in micelles improves its stability, antioxidant, and anti-inflammatory activity.


Asunto(s)
Antioxidantes , Quitosano , Curcumina , Micelas , Curcumina/farmacología , Curcumina/química , Quitosano/química , Antioxidantes/farmacología , Antioxidantes/química , Nanopartículas/química , Animales , Pez Cebra , Portadores de Fármacos/química , Interacciones Hidrofóbicas e Hidrofílicas , Tamaño de la Partícula , Tensoactivos/química
6.
Genes (Basel) ; 15(6)2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38927595

RESUMEN

Ageing has been identified as an independent risk factor for various diseases; however, the physiological basis and molecular changes related to ageing are still largely unknown. Here, we show that the level of APPL2, an adaptor protein, is significantly reduced in the major organs of aged mice. Knocking down APPL2 causes premature ageing of human umbilical vein endothelial cells (HUVECs). We find that a lack of T04C9.1, the homologue of mammalian APPL2, leads to premature ageing, slow movements, lipid deposition, decreased resistance to stresses, and shortened lifespan in Caenorhabditis elegans (C. elegans), which are associated with decreased autophagy. Activating autophagy by rapamycin or inhibition of let-363 suppresses the age-related alternations, impaired motility, and shortened lifespan of C. elegans, which are reversed by knocking down autophagy-related genes. Our work provides evidence that APPL2 and its C. elegans homologue T04C9.1 decrease with age and reveals that a lack of T04C9.1 bridges autophagy decline and ageing in C. elegans.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Autofagia , Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Longevidad , Animales , Humanos , Ratones , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Envejecimiento/genética , Envejecimiento Prematuro/genética , Autofagia/genética , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Longevidad/genética
7.
Dev Cell ; 59(10): 1233-1251.e5, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38569546

RESUMEN

De novo brown adipogenesis holds potential in combating the epidemics of obesity and diabetes. However, the identity of brown adipocyte progenitor cells (APCs) and their regulation have not been extensively explored. Here, through in vivo lineage tracing and mouse modeling, we observed that platelet-derived growth factor receptor beta (PDGFRß)+ pericytes give rise to developmental brown adipocytes but not to those in adult homeostasis. By contrast, T-box 18 (TBX18)+ pericytes contribute to brown adipogenesis throughout both developmental and adult stages, though in a depot-specific manner. Mechanistically, Notch inhibition in PDGFRß+ pericytes promotes brown adipogenesis by downregulating PDGFRß. Furthermore, inhibition of Notch signaling in PDGFRß+ pericytes mitigates high-fat, high-sucrose (HFHS)-induced glucose and metabolic impairment in mice during their development and juvenile phases. Collectively, these findings show that the Notch/PDGFRß axis negatively regulates developmental brown adipogenesis, and its repression promotes brown adipose tissue expansion and improves metabolic health.


Asunto(s)
Adipocitos Marrones , Adipogénesis , Diferenciación Celular , Receptor beta de Factor de Crecimiento Derivado de Plaquetas , Receptores Notch , Células Madre , Animales , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Receptores Notch/metabolismo , Ratones , Adipocitos Marrones/metabolismo , Adipocitos Marrones/citología , Células Madre/metabolismo , Células Madre/citología , Transducción de Señal , Pericitos/metabolismo , Pericitos/citología , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Pardo/citología , Ratones Endogámicos C57BL , Masculino
8.
Cell Rep ; 43(5): 114169, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38678562

RESUMEN

Sympathetic innervation of brown adipose tissue (BAT) controls mammalian adaptative thermogenesis. However, the cellular and molecular underpinnings contributing to BAT innervation remain poorly defined. Here, we show that smooth muscle cells (SMCs) support BAT growth, lipid utilization, and thermogenic plasticity. Moreover, we find that BAT SMCs express and control the bioavailability of Cxcl12. SMC deletion of Cxcl12 fosters brown adipocyte lipid accumulation, reduces energy expenditure, and increases susceptibility to diet-induced metabolic dysfunction. Mechanistically, we find that Cxcl12 stimulates CD301+ macrophage recruitment and supports sympathetic neuronal maintenance. Administering recombinant Cxcl12 to obese mice or leptin-deficient (Ob/Ob) mice is sufficient to boost macrophage presence and drive sympathetic innervation to restore BAT morphology and thermogenic responses. Altogether, our data reveal an SMC chemokine-dependent pathway linking immunological infiltration and sympathetic innervation as a rheostat for BAT maintenance and thermogenesis.


Asunto(s)
Tejido Adiposo Pardo , Quimiocina CXCL12 , Macrófagos , Miocitos del Músculo Liso , Sistema Nervioso Simpático , Termogénesis , Animales , Quimiocina CXCL12/metabolismo , Macrófagos/metabolismo , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Pardo/inervación , Ratones , Miocitos del Músculo Liso/metabolismo , Sistema Nervioso Simpático/metabolismo , Sistema Nervioso Simpático/fisiología , Ratones Endogámicos C57BL , Masculino , Metabolismo Energético , Obesidad/metabolismo , Obesidad/patología
9.
Mol Cell Biochem ; 2024 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-38430300

RESUMEN

While P21-activated kinase-1 (PAK1) has been extensively studied in relation to cardiovascular health and glucose metabolism, its roles within adipose tissue and cardiometabolic diseases are less understood. In this study, we explored the effects of PAK1 deletion on energy balance, adipose tissue homeostasis, and cardiac function utilizing a whole-body PAK1 knockout (PAK1-/-) mouse model. Our findings revealed that body weight differences between PAK1-/- and WT mice emerged at 9 weeks of age, with further increases observed at 12 weeks. Furthermore, PAK1-/- mice displayed increased fat mass and decreased lean mass at 12 weeks, indicating a shift towards adiposity. In conjunction with the increased body weight, PAK1-/- mice had increased food intake and reduced energy expenditure. At a mechanistic level, PAK1 deletion boosted the expression of lipogenic markers while diminishing thermogenic markers expression in adipose tissues, contributing to reduced energy expenditure and the overall obesogenic phenotype. Moreover, our findings highlighted a significant impact on cardiac function following PAK1 deletion, including alterations in calcium kinetics and compromised systolic and lusitropy functions. In summary, our study emphasizes the significant role of PAK1 in weight regulation and cardiac function, enriching our comprehension of heart health and metabolism. These findings could potentially facilitate the identification of novel therapeutic targets in cardiometabolic diseases.

10.
J Ethnopharmacol ; 326: 117927, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38373665

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Jiawei Yanghe Decoction (JWYHD) is modified Yanghe Decoction (YHD). YHD historically utilized as a potent medicinal solution for addressing chronic inflammatory conditions, holds promising therapeutic potential in the treatment of asthma. However, the mechanisms underlying JWYHD's effects on allergic asthma remain unclear. AIM OF THE STUDY: To investigate the therapeutic effect as well as the underlying mechanisms of JWYHD on asthmatic mice. MATERIALS AND METHODS: The ovalbumin (OVA)-induced mouse model was utilized, followed by the administration of JWYHD to allergic asthmatic mice. Subsequently, inflammatory cells in the bronchoalveolar lavage fluid (BALF) and lung tissues were conducted. The levels of various cytokines including interleukin (IL)-4, IL-5, IL-13, IL-33, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ in BALF, as well as the total immunoglobulin E (IgE) content in serum, were assessed. Lung function and tissue pathology examinations were performed to assess the protective impacts of JWYHD. The chemical components of JWYHD and its lung prototype compounds (referred to the chemical components present in JWYHD that were observed in the lung) were explored by ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS). RNA-seq analysis revealed the regulation mechanisms of JWYHD treating asthma. Furthermore, the effect of JWYHD on type 2 innate lymphoid cells (ILC2s) in asthmatic mice was detected by flow cytometry and Smart-RNA-seq analysis. Then molecular docking analysis was used to show the interaction between identified compounds and key targets. RESULTS: JWYHD significantly attenuated the airway inflammation of asthmatic mice, reduced the levels of inflammatory cells in BALF, as well the levels of the cytokines IL-4, IL-5, IL-13, IL-33, and TNF-α in BALF and IgE in serum. Airway hyperresponsiveness (AHR) and lung inflammation infiltration were also alleviated by JWYHD. Moreover, RNA-seq analysis revealed that JWYHD attenuated airway inflammation in asthmatic mice via regulating immunity. Flow cytometry confirmed that JWYHD could inhibit ILC2 responses. ILC2 Smart-RNA-seq analysis showed that JWYHD impaired the inflammation reaction-related signaling pathways in ILC2s, and neuropilin-1 (Nrp1), endothelial transcription factor 3 (GATA3) and interleukin 1 receptor like protein 1 (ST2) might be the key targets. The molecular docking analysis investigating the connection between the primary targets and JWYHD's prototype compounds in the lung demonstrated that liquiritin apioside, icariin, glycyrrhizic acid, and uralsaponin B, identified through UPLC-Q-TOF/MS, exhibited significant affinity in binding to the mentioned key targets. CONCLUSION: Our results suggested that the mechanism of JWYHD in treating asthma might be related to limiting ILC2 responses. Our findings provided some pharmacological evidence for the clinical application of JWYHD in the treatment of asthma.


Asunto(s)
Asma , Medicamentos Herbarios Chinos , Inmunidad Innata , Ratones , Animales , Interleucina-33 , Interleucina-13 , Interleucina-5 , Simulación del Acoplamiento Molecular , Linfocitos/metabolismo , Pulmón , Inflamación/tratamiento farmacológico , Inflamación/patología , Citocinas/metabolismo , Líquido del Lavado Bronquioalveolar , Inmunoglobulina E , Ovalbúmina/farmacología , Ratones Endogámicos BALB C , Modelos Animales de Enfermedad
11.
Sci Total Environ ; 915: 169962, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38219999

RESUMEN

BACKGROUND: Exposure to semi-volatile organic compounds (SVOCs) may link to thyroid nodule risk, but studies of mixed-SVOCs exposure effects are lacking. Traditional analytical methods are inadequate for dealing with mixed exposures, while machine learning (ML) seems to be a good way to fill the gaps in the field of environmental epidemiology research. OBJECTIVES: Different ML algorithms were used to explore the relationship between mixed-SVOCs exposure and thyroid nodule. METHODS: A 1:1:1 age- and gender-matched case-control study was conducted in which 96 serum SVOCs were measured in 50 papillary thyroid carcinoma (PTC), 50 nodular goiters (NG), and 50 controls. Different ML techniques such as Random Forest, AdaBoost were selected based on their predictive power, and variables were selected based on their weights in the models. Weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) were used to assess the mixed effects of the SVOCs exposure on thyroid nodule. RESULTS: Forty-three of 96 SVOCs with detection rate >80 % were included in the analysis. ML algorithms showed a consistent selection of SVOCs associated with thyroid nodule. Fluazifop-butyl and fenpropathrin are positively associated with PTC and NG in single compound models (all P < 0.05). WQS model shows that exposure to mixed-SVOCs was associated with an increased risk of PTC and NG, with the mixture dominated by fenpropathrin, followed by fluazifop-butyl and propham. In the BKMR model, mixtures showed a significant positive association with thyroid nodule risk at high exposure levels, and fluazifop-butyl showed positive effects associated with PTC and NG. CONCLUSION: This study confirms the feasibility of ML methods for variable selection in high-dimensional complex data and showed that mixed exposure to SVOCs was associated with increased risk of PTC and NG. The observed association was primarily driven by fluazifop-butyl and fenpropathrin. The findings warranted further investigation.


Asunto(s)
Contaminantes Ambientales , Bocio Nodular , Piretrinas , Neoplasias de la Tiroides , Nódulo Tiroideo , Compuestos Orgánicos Volátiles , Humanos , Cáncer Papilar Tiroideo , Bocio Nodular/patología , Estudios de Casos y Controles , Teorema de Bayes , Algoritmos , Aprendizaje Automático
12.
iScience ; 27(1): 108682, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38235323

RESUMEN

White adipose tissue (WAT) development and adult homeostasis rely on distinct adipocyte progenitor cells (APCs). While adult APCs are defined early during embryogenesis and generate adipocytes after WAT organogenesis, the mechanisms underlying adult adipose lineage determination and preservation remain undefined. Here, we uncover a critical role for platelet-derived growth factor receptor beta (Pdgfrß) in identifying the adult APC lineage. Without Pdgfrß, APCs lose their adipogenic competency to incite fibrotic tissue replacement and inflammation. Through lineage tracing analysis, we reveal that the adult APC lineage is lost and develops into macrophages when Pdgfrß is deleted embryonically. Moreover, to maintain the APC lineage, Pdgfrß activation stimulates p38/MAPK phosphorylation to promote APC proliferation and maintains the APC state by phosphorylating peroxisome proliferator activated receptor gamma (Pparγ) at serine 112. Together, our findings identify a role for Pdgfrß acting as a rheostat for adult adipose lineage confinement to prevent unintended lineage switches.

13.
Metabolism ; 151: 155740, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37995805

RESUMEN

BACKGROUND & AIMS: Dysbiosis contributes to alcohol-associated liver disease (ALD); however, the precise mechanisms remain elusive. Given the critical role of the gut microbiota in ammonia production, we herein aim to investigate whether and how gut-derived ammonia contributes to ALD. METHODS: Blood samples were collected from human subjects with/without alcohol drinking. Mice were exposed to the Lieber-DeCarli isocaloric control or ethanol-containing diets with and without rifaximin (a nonabsorbable antibiotic clinically used for lowering gut ammonia production) supplementation for five weeks. Both in vitro (NH4Cl exposure of AML12 hepatocytes) and in vivo (urease administration for 5 days in mice) hyperammonemia models were employed. RNA sequencing and fecal amplicon sequencing were performed. Ammonia and triglyceride concentrations were measured. The gene and protein expression of enzymes involved in multiple pathways were measured. RESULTS: Chronic alcohol consumption causes hyperammonemia in both mice and human subjects. In healthy livers and hepatocytes, ammonia exposure upregulates the expression of urea cycle genes, elevates hepatic de novo lipogenesis (DNL), and increases fat accumulation. Intriguingly, ammonia promotes ethanol catabolism and acetyl-CoA formation, which, together with ammonia, synergistically facilitates intracellular fat accumulation in hepatocytes. Mechanistic investigations uncovered that ATF4 activation, as a result of ER stress induction and general control nonderepressible 2 activation, plays a central role in ammonia-provoked DNL elevation. Rifaximin ameliorates ALD pathologies in mice, concomitant with blunted hepatic ER stress induction, ATF4 activation, and DNL activation. CONCLUSIONS: An overproduction of ammonia by gut microbiota, synergistically interacting with ethanol, is a significant contributor to ALD pathologies.


Asunto(s)
Amoníaco , Hígado Graso , Hiperamonemia , Hepatopatías Alcohólicas , Animales , Humanos , Ratones , Factor de Transcripción Activador 4/genética , Factor de Transcripción Activador 4/metabolismo , Amoníaco/efectos adversos , Amoníaco/metabolismo , Etanol/efectos adversos , Etanol/metabolismo , Hígado Graso/inducido químicamente , Hígado Graso/metabolismo , Hiperamonemia/complicaciones , Hiperamonemia/metabolismo , Hiperamonemia/patología , Lipogénesis , Hígado/metabolismo , Hepatopatías Alcohólicas/metabolismo , Ratones Endogámicos C57BL , Rifaximina/farmacología
14.
G3 (Bethesda) ; 14(2)2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-37889998

RESUMEN

Tra1 is an essential coactivator protein of the yeast SAGA and NuA4 acetyltransferase complexes that regulate gene expression through multiple mechanisms including the acetylation of histone proteins. Tra1 is a pseudokinase of the PIKK family characterized by a C-terminal PI3K domain with no known kinase activity. However, mutations of specific arginine residues to glutamine in the PI3K domains (an allele termed tra1Q3) result in reduced growth and increased sensitivity to multiple stresses. In the opportunistic fungal pathogen Candida albicans, the tra1Q3 allele reduces pathogenicity and increases sensitivity to the echinocandin antifungal drug caspofungin, which disrupts the fungal cell wall. Here, we found that compromised Tra1 function, in contrast to what is seen with caspofungin, increases tolerance to the azole class of antifungal drugs, which inhibits ergosterol synthesis. In C. albicans, tra1Q3 increases the expression of genes linked to azole resistance, such as ERG11 and CDR1. CDR1 encodes a multidrug ABC transporter associated with efflux of multiple xenobiotics, including azoles. Consequently, cells carrying tra1Q3 show reduced intracellular accumulation of fluconazole. In contrast, a tra1Q3 Saccharomyces cerevisiae strain displayed opposite phenotypes: decreased tolerance to azole, decreased expression of the efflux pump PDR5, and increased intracellular accumulation of fluconazole. Therefore, our data provide evidence that Tra1 differentially regulates the antifungal response across yeast species.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Antifúngicos/farmacología , Antifúngicos/metabolismo , Azoles/farmacología , Azoles/metabolismo , Fluconazol/farmacología , Fluconazol/metabolismo , Caspofungina , Filogenia , Candida albicans/genética , Candida albicans/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Farmacorresistencia Fúngica/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Pruebas de Sensibilidad Microbiana , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Histona Acetiltransferasas/química
15.
Mol Neurodegener ; 18(1): 82, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37950311

RESUMEN

The lack of effective therapies that slow the progression of Alzheimer's disease (AD) and related tauopathies highlights the need for a more comprehensive understanding of the fundamental cellular mechanisms underlying these diseases. Model organisms, including yeast, worms, and flies, provide simple systems with which to investigate the mechanisms of disease. The evolutionary conservation of cellular pathways regulating proteostasis and stress response in these organisms facilitates the study of genetic factors that contribute to, or protect against, neurodegeneration. Here, we review genetic modifiers of neurodegeneration and related cellular pathways identified in the budding yeast Saccharomyces cerevisiae, the nematode Caenorhabditis elegans, and the fruit fly Drosophila melanogaster, focusing on models of AD and related tauopathies. We further address the potential of simple model systems to better understand the fundamental mechanisms that lead to AD and other neurodegenerative disorders.


Asunto(s)
Enfermedad de Alzheimer , Tauopatías , Animales , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Proteínas tau/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Modelos Animales de Enfermedad , Tauopatías/genética , Tauopatías/metabolismo , Caenorhabditis elegans/metabolismo , Drosophila/metabolismo
16.
Biomolecules ; 13(11)2023 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-38002276

RESUMEN

Although amphiphilic chitosan has been widely studied as a drug carrier for drug delivery, fewer studies have been conducted on the antimicrobial activity of amphiphilic chitosan. In this study, we successfully synthesized deoxycholic acid-modified chitosan (CS-DA) by grafting deoxycholic acid (DA) onto chitosan C2-NH2, followed by grafting succinic anhydride, to prepare a novel amphiphilic chitosan (CS-DA-SA). The substitution degree was 23.93% for deoxycholic acid and 29.25% for succinic anhydride. Both CS-DA and CS-DA-SA showed good blood compatibility. Notably, the synthesized CS-DA-SA can self-assemble to form nanomicelles at low concentrations in an aqueous environment. The results of CS, CS-DA, and CS-DA-SA against Escherichia coli and Staphylococcus aureus showed that CS-DA and CS-DA-SA exhibited stronger antimicrobial effects than CS. CS-DA-SA may exert its antimicrobial effect by disrupting cell membranes or forming a membrane on the cell surface. Overall, the novel CS-DA-SA biomaterials have a promising future in antibacterial therapy.


Asunto(s)
Quitosano , Quitosano/farmacología , Anhídridos Succínicos , Micelas , Antibacterianos/farmacología , Ácido Desoxicólico/farmacología
17.
Front Psychiatry ; 14: 1238973, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37654990

RESUMEN

This systematic review aims to offer an updated understanding of the relationship between omega-3 supplementation and/or vitamin D and autism spectrum disorders (ASD). The databases PubMed, Cochrane Library, Web of Science, EMBASE, CINAHL, Vip, CNKI, Wanfang, China Biomedical Database databases were searched using keywords, and relevant literature was hand-searched. Papers (n = 1,151) were systematically screened and deemed eligible since 2002. Twenty clinical controlled studies were included in the final review. The findings were analyzed for intervention effects focusing on the core symptoms of ASD, included social functioning, behavioral functioning, speech function and biomarkers changes. The review found that the effects of omega-3 supplementation on ASD were too weak to conclude that core symptoms were alleviated. Vitamin D supplementation improved core symptoms, particularly behavioral functioning, however, the results of the literatures included in this study were slightly mixed, we cannot directly conclude that vitamin D supplementation has a beneficial effect on a specific symptom of ASD, but the overall conclusion is that vitamin D supplementation has a positive effect on behavioral functioning in ASD. Omega-3 and vitamin D combination supplementation has a good combined effect on social and behavioral outcomes in patients with ASD.

18.
J Colloid Interface Sci ; 652(Pt B): 1271-1281, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37659300

RESUMEN

Solar interfacial evaporation is a highly promising technology for seawater desalination and wastewater treatment, while the simple preparation processes and efficient production of clean water based on biomass interfacial evaporators still need further exploration and development. Here, we reported a wood-based evaporator (PFDW) loaded with Fe3O4 and polydopamine (PDA) after simple immersion treatment at room temperature for efficient and continuous water purification. The synergistic photothermal effect of PDA coating and Fe3O4 particles enables the evaporator to achieve high photothermal conversion efficiency in the longer wavelength range, while combined with the rapid water transport capacity endowed by the vertically aligned microporous structure of natural wood, it achieved an evaporation rate of 1.70 kg m-2h-1 and an energy efficiency of 98.0% under 1 kW m-2 irradiation. In addition, the prepared PFDW exhibited sustainable desalination stability and excellent removal efficiency for different water sources including organic dye wastewater, heavy metal effluent, oil-water emulsion and river water. This work provides a new avenue for efficient salt-tolerant portable evaporators.

19.
bioRxiv ; 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37693431

RESUMEN

Thermogenic beige adipocytes are recognized as potential therapeutic targets for combating metabolic diseases. However, the metabolic advantages they offer are compromised with aging. Here, we show that treating mice with estrogen (E2), a hormone that decreases with age, to mice can counteract the aging- related decline in beige adipocyte formation when subjected to cold, while concurrently enhancing energy expenditure and improving glucose tolerance. Mechanistically, we find that nicotinamide phosphoribosyltranferase (NAMPT) plays a pivotal role in facilitating the formation of E2-induced beige adipocytes, which subsequently suppresses the onset of age-related ER stress. Furthermore, we found that targeting NAMPT signaling, either genetically or pharmacologically, can restore the formation of beige adipocytes by increasing the number of perivascular adipocyte progenitor cells. Conversely, the absence of NAMPT signaling prevents this process. In conclusion, our findings shed light on the mechanisms governing the age-dependent impairment of beige adipocyte formation and underscore the E2-NAMPT controlled ER stress as a key regulator of this process. Highlights: Estrogen restores beige adipocyte failure along with improved energy metabolism in old mice.Estrogen enhances the thermogenic gene program by mitigating age-induced ER stress.Estrogen enhances the beige adipogenesis derived from SMA+ APCs.Inhibiting the NAMPT signaling pathway abolishes estrogen-promoted beige adipogenesis.

20.
Mol Biotechnol ; 2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37642828

RESUMEN

Tamoxifen (TAM) is commonly administered to a variety of inducible or conditional transgenic mice that contain Cre recombinase fused with ER. While the impacts of adult TAM treatment are well documented in the field of adipose biology, the long-term effects of postnatal TAM treatment on adult life are still understudied. In this study, we investigated whether postnatal TAM treatment had long-lasting effects on adult body composition and adiposity in male and female mice, fed either with chow or a high-fat diet (HFD). We found that postnatal, but not adult, TAM treatment had long-lasting impacts on female mice, resulting in lower body weight, lower fat mass, and smaller adipocytes. In contrast, postnatal exposure to TAM impaired male but not female cold-induced adipose beiging capacity. Interestingly, upon HFD feeding, the sex-dependent effects of TAM on adult life disappeared, and both female and male mice showed a more obese phenotype with impaired glucose tolerance. These findings suggest that postnatal TAM injection exerts a long-lasting impact on adipose tissue in adult life in a sex- and diet-dependent manner.

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