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1.
Cell ; 178(1): 176-189.e15, 2019 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-31155231

RESUMEN

RLR-mediated type I IFN production plays a pivotal role in elevating host immunity for viral clearance and cancer immune surveillance. Here, we report that glycolysis, which is inactivated during RLR activation, serves as a barrier to impede type I IFN production upon RLR activation. RLR-triggered MAVS-RIG-I recognition hijacks hexokinase binding to MAVS, leading to the impairment of hexokinase mitochondria localization and activation. Lactate serves as a key metabolite responsible for glycolysis-mediated RLR signaling inhibition by directly binding to MAVS transmembrane (TM) domain and preventing MAVS aggregation. Notably, lactate restoration reverses increased IFN production caused by lactate deficiency. Using pharmacological and genetic approaches, we show that lactate reduction by lactate dehydrogenase A (LDHA) inactivation heightens type I IFN production to protect mice from viral infection. Our study establishes a critical role of glycolysis-derived lactate in limiting RLR signaling and identifies MAVS as a direct sensor of lactate, which functions to connect energy metabolism and innate immunity.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteína 58 DEAD Box/antagonistas & inhibidores , Proteína 58 DEAD Box/metabolismo , Ácido Láctico/farmacología , Receptores de Superficie Celular/antagonistas & inhibidores , Receptores de Superficie Celular/metabolismo , Animales , Femenino , Glucólisis , Células HEK293 , Humanos , Interferón beta/metabolismo , L-Lactato Deshidrogenasa/genética , L-Lactato Deshidrogenasa/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Células RAW 264.7 , Receptores Inmunológicos , Transducción de Señal/efectos de los fármacos , Transfección
2.
Immunity ; 57(1): 106-123.e7, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38159573

RESUMEN

When the filtrate of the glomerulus flows through the renal tubular system, various microscopic sediment particles, including mineral crystals, are generated. Dislodging these particles is critical to ensuring the free flow of filtrate, whereas failure to remove them will result in kidney stone formation and obstruction. However, the underlying mechanism for the clearance is unclear. Here, using high-resolution microscopy, we found that the juxtatubular macrophages in the renal medulla constitutively formed transepithelial protrusions and "sampled" urine contents. They efficiently sequestered and phagocytosed intraluminal sediment particles and occasionally transmigrated to the tubule lumen to escort the excretion of urine particles. Mice with decreased renal macrophage numbers were prone to developing various intratubular sediments, including kidney stones. Mechanistically, the transepithelial behaviors of medulla macrophages required integrin ß1-mediated ligation to the tubular epithelium. These findings indicate that medulla macrophages sample urine content and remove intratubular particles to keep the tubular system unobstructed.


Asunto(s)
Cálculos Renales , Riñón , Ratones , Animales , Macrófagos
3.
Mol Cell ; 80(2): 263-278.e7, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-33022274

RESUMEN

Cancer metastasis accounts for the major cause of cancer-related deaths. How disseminated cancer cells cope with hostile microenvironments in secondary site for full-blown metastasis is largely unknown. Here, we show that AMPK (AMP-activated protein kinase), activated in mouse metastasis models, drives pyruvate dehydrogenase complex (PDHc) activation to maintain TCA cycle (tricarboxylic acid cycle) and promotes cancer metastasis by adapting cancer cells to metabolic and oxidative stresses. This AMPK-PDHc axis is activated in advanced breast cancer and predicts poor metastasis-free survival. Mechanistically, AMPK localizes in the mitochondrial matrix and phosphorylates the catalytic alpha subunit of PDHc (PDHA) on two residues S295 and S314, which activates the enzymatic activity of PDHc and alleviates an inhibitory phosphorylation by PDHKs, respectively. Importantly, these phosphorylation events mediate PDHc function in cancer metastasis. Our study reveals that AMPK-mediated PDHA phosphorylation drives PDHc activation and TCA cycle to empower cancer cells adaptation to metastatic microenvironments for metastasis.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Ciclo del Ácido Cítrico , Complejo Piruvato Deshidrogenasa/metabolismo , Animales , Dominio Catalítico , Línea Celular Tumoral , Supervivencia Celular , Activación Enzimática , Femenino , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Metástasis de la Neoplasia , Fosforilación , Fosfoserina/metabolismo , Transducción de Señal , Estrés Fisiológico , Análisis de Supervivencia
4.
Nature ; 597(7874): 57-63, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34471277

RESUMEN

Fibre lithium-ion batteries are attractive as flexible power solutions because they can be woven into textiles, offering a convenient way to power future wearable electronics1-4. However, they are difficult to produce in lengths of more than a few centimetres, and longer fibres were thought to have higher internal resistances3,5 that compromised electrochemical performance6,7. Here we show that the internal resistance of such fibres has a hyperbolic cotangent function relationship with fibre length, where it first decreases before levelling off as length increases. Systematic studies confirm that this unexpected result is true for different fibre batteries. We are able to produce metres of high-performing fibre lithium-ion batteries through an optimized scalable industrial process. Our mass-produced fibre batteries have an energy density of 85.69 watt hour per kilogram (typical values8 are less than 1 watt hour per kilogram), based on the total weight of a lithium cobalt oxide/graphite full battery, including packaging. Its capacity retention reaches 90.5% after 500 charge-discharge cycles and 93% at 1C rate (compared with 0.1C rate capacity), which is comparable to commercial batteries such as pouch cells. Over 80 per cent capacity can be maintained after bending the fibre for 100,000 cycles. We show that fibre lithium-ion batteries woven into safe and washable textiles by industrial rapier loom can wirelessly charge a cell phone or power a health management jacket integrated with fibre sensors and a textile display.


Asunto(s)
Cobalto/química , Suministros de Energía Eléctrica , Electrónica , Litio/química , Óxidos/química , Textiles , Dispositivos Electrónicos Vestibles , Grafito/química , Humanos , Iones , Masculino , Tecnología Inalámbrica
5.
Proc Natl Acad Sci U S A ; 119(39): e2211234119, 2022 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-36122246

RESUMEN

Whether or not nonavian dinosaur biodiversity declined prior to the end-Cretaceous mass extinction remains controversial as the result of sampling biases in the fossil record, differences in the analytical approaches used, and the rarity of high-precision geochronological dating of dinosaur fossils. Using magnetostratigraphy, cyclostratigraphy, and biostratigraphy, we establish a high-resolution geochronological framework for the fossil-rich Late Cretaceous sedimentary sequence in the Shanyang Basin of central China. We have found only three dinosaurian eggshell taxa (Macroolithus yaotunensis, Elongatoolithus elongatus, and Stromatoolithus pinglingensis) representing two clades (Oviraptoridae and Hadrosauridae) in sediments deposited between ∼68.2 and ∼66.4 million y ago, indicating sustained low dinosaur biodiversity, and that assessment is consistent with the known skeletal remains in the Shanyang and surrounding basins of central China. Along with the dinosaur eggshell records from eastern and southern China, we find a decline in dinosaur biodiversity from the Campanian to the Maastrichtian. Our results support a long-term decline in global dinosaur biodiversity prior to 66 million y ago, which likely set the stage for the end-Cretaceous nonavian dinosaur mass extinction.


Asunto(s)
Biodiversidad , Dinosaurios , Extinción Biológica , Fósiles , Animales , China , Dinosaurios/clasificación
6.
Kidney Int ; 105(4): 759-774, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38296028

RESUMEN

Lupus nephritis (LN) is one of the most severe manifestations of systemic lupus erythematosus (SLE), but its mechanism of onset remains unclear. Since impaired mitophagy has been implicated in multiple organs in SLE, we hypothesized that mitophagy dysfunction is critical in the development of LN and that pharmacologically targeting mitophagy would ameliorate this disease. Therefore, lupus-prone MRL/MpJ-Faslpr (MRL/lpr) and NZBWF1/J mice were treated with a novel mitophagy inducer, UMI-77, during their onset of LN. This treatment effectively mitigated kidney inflammation and damage as assessed by histology and flow cytometry. Furthermore, dendritic cell (DC)-T-cell coculture assay indicated that UMI-77 treatment attenuated DC function that would drive T-cell proliferation but did not directly influence the potent T-cell proliferation in lupus mice. UMI-77 also restored mitochondrial function and attenuated proinflammatory phenotypes in lupus DCs. Adoptive transfer of DCs from MRL/lpr mice augmented serum anti-dsDNA IgG, urine protein and T-cell infiltration of the kidney in MRL/MpJ mice, which could be prevented by either treating lupus donors in vivo or lupus DCs directly with UMI-77. UMI-77 also restored mitochondrial function in myeloid cells from patients with LN in vitro as evidenced by increased ATP levels. Thus, enhancing mitophagy in SLE restrains autoimmunity and limits kidney inflammation for LN development. Hence, our findings suggest targeting mitophagy as a tangible pathway to treat LN.


Asunto(s)
Lupus Eritematoso Sistémico , Nefritis Lúpica , Sulfonamidas , Tioglicolatos , Humanos , Ratones , Animales , Nefritis Lúpica/patología , Autoantígenos , Mitofagia , Ratones Endogámicos MRL lpr , Riñón/patología , Células Mieloides , Inflamación/patología
7.
Clin Immunol ; 261: 109941, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38365047

RESUMEN

Chronic rejection is the primary cause of late allograft failure, however, the current treatments for chronic rejection have not yielded desirable therapeutic effects. B cell activation and donor-specific antibody (DSA) production are the primary factors leading to chronic rejection. Bruton's tyrosine kinase (BTK) plays a key role in the activation and differentiation of B cells and in antibody production. This study investigated the efficacy of blocking BTK signalling in the prevention of chronic rejection. BTK signalling was blocked using the BTK inhibitor ibrutinib and gene knockout. In vitro assays were conducted to examine the consequences and underlying mechanisms of BTK blockade in regards to B cell activation, differentiation, and antibody secretion. Additionally, we established a cardiac transplantation mouse model of chronic rejection to explore the preventive effects and mechanisms of BTK ablation on chronic rejection. Ablating BTK signalling in vitro resulted in the inhibition of B cell activation, differentiation, and antibody production. In vivo experiments provided evidence that ablating BTK signalling alleviated chronic rejection, leading to reduced damage in myocardial tissue, neointimal hyperplasia, interstitial fibrosis, inflammatory cell infiltration, and C4d deposition. Allograft survival was prolonged, and B cell responses and DSA production were inhibited as a result. We confirmed that ablation of BTK signalling inhibited B cell response by blocking downstream PLCγ2 phosphorylation and inhibiting the NF-κB, NFAT, and ERK pathways. Our findings demonstrated that ablation of BTK signalling inhibited B cell activation and differentiation, reduced DSA production, and effectively prevented chronic rejection.


Asunto(s)
Formación de Anticuerpos , Trasplante de Corazón , Animales , Ratones , Agammaglobulinemia Tirosina Quinasa , Linfocitos B , Transducción de Señal
8.
Small ; : e2401334, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38804884

RESUMEN

Lung cancer, a highly prevalent and lethal form of cancer, is often associated with oxidative stress. Photodynamic therapy (PDT) has emerged as a promising alternative therapeutic tool in cancer treatments, but its efficacy is closely correlated to the photosensitizers generating reactive oxygen species (ROS) and the antioxidant capacity of tumor cells. In particular, glutathione (GSH) can reduce the ROS and thus compromise PDT efficacy. In this study, a GSH-responsive near-infrared photosensitizer (TBPPN) based on aggregation-induced emission for real-time monitoring of GSH levels and enhanced PDT for lung cancer treatment is developed. The strategic design of TBPPN, consisting of a donor-acceptor structure and incorporation of dinitrobenzene, enables dual functionality by not only the fluorescence being activated by GSH but also depleting GSH to enhance the cytotoxic effect of PDT. TBPPN demonstrates synergistic PDT efficacy in vitro against A549 lung cancer cells by specifically targeting different cellular compartments and depleting intracellular GSH. In vivo studies further confirm that TBPPN can effectively inhibit tumor growth in a mouse model with lung cancer, highlighting its potential as an integrated agent for the diagnosis and treatment of lung cancer. This approach enhances the effectiveness of PDT for lung cancer and deserves further exploration of its potential for clinical application.

9.
J Transl Med ; 22(1): 465, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755664

RESUMEN

Disturbance in mitochondrial homeostasis within proximal tubules is a critical characteristic associated with diabetic kidney disease (DKD). CaMKKß/AMPK signaling plays an important role in regulating mitochondrial homeostasis. Despite the downregulation of CaMKKß in DKD pathology, the underlying mechanism remains elusive. The expression of NEDD4L, which is primarily localized to renal proximal tubules, is significantly upregulated in the renal tubules of mice with DKD. Coimmunoprecipitation (Co-IP) assays revealed a physical interaction between NEDD4L and CaMKKß. Moreover, deletion of NEDD4L under high glucose conditions prevented rapid CaMKKß protein degradation. In vitro studies revealed that the aberrant expression of NEDD4L negatively influences the protein stability of CaMKKß. This study also explored the role of NEDD4L in DKD by using AAV-shNedd4L in db/db mice. These findings confirmed that NEDD4L inhibition leads to a decrease in urine protein excretion, tubulointerstitial fibrosis, and oxidative stress, and mitochondrial dysfunction. Further in vitro studies demonstrated that si-Nedd4L suppressed mitochondrial fission and reactive oxygen species (ROS) production, effects antagonized by si-CaMKKß. In summary, the findings provided herein provide strong evidence that dysregulated NEDD4L disturbs mitochondrial homeostasis by negatively modulating CaMKKß in the context of DKD. This evidence underscores the potential of therapeutic interventions targeting NEDD4L and CaMKKß to safeguard renal tubular function in the management of DKD.


Asunto(s)
Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina , Nefropatías Diabéticas , Regulación hacia Abajo , Homeostasis , Mitocondrias , Ubiquitina-Proteína Ligasas Nedd4 , Animales , Ubiquitina-Proteína Ligasas Nedd4/metabolismo , Ubiquitina-Proteína Ligasas Nedd4/genética , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Mitocondrias/metabolismo , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/metabolismo , Ratones Endogámicos C57BL , Ratones , Humanos , Especies Reactivas de Oxígeno/metabolismo , Masculino , Estrés Oxidativo , Dinámicas Mitocondriales , Estabilidad Proteica , Proteolisis
10.
Magn Reson Med ; 92(3): 1149-1161, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38650444

RESUMEN

PURPOSE: To improve image quality, mitigate quantification biases and variations for free-breathing liver proton density fat fraction (PDFF) and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ quantification accelerated by radial k-space undersampling. METHODS: A free-breathing multi-echo stack-of-radial MRI method was developed with compressed sensing with multidimensional regularization. It was validated in motion phantoms with reference acquisitions without motion and in 11 subjects (6 patients with nonalcoholic fatty liver disease) with reference breath-hold Cartesian acquisitions. Images, PDFF, and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ maps were reconstructed using different radial view k-space sampling factors and reconstruction settings. Results were compared with reference-standard results using Bland-Altman analysis. Using linear mixed-effects model fitting (p < 0.05 considered significant), mean and SD were evaluated for biases and variations of PDFF and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ , respectively, and coefficient of variation on the first echo image was evaluated as a surrogate for image quality. RESULTS: Using the empirically determined optimal sampling factor of 0.25 in the accelerated in vivo protocols, mean differences and limits of agreement for the proposed method were [-0.5; -33.6, 32.7] s-1 for R 2 * $$ {\mathrm{R}}_2^{\ast } $$ and [-1.0%; -5.8%, 3.8%] for PDFF, close to those of a previous self-gating method using fully sampled radial views: [-0.1; -27.1, 27.0] s-1 for R 2 * $$ {\mathrm{R}}_2^{\ast } $$ and [-0.4%; -4.5%, 3.7%] for PDFF. The proposed method had significantly lower coefficient of variation than other methods (p < 0.001). Effective acquisition time of 64 s or 59 s was achieved, compared with 171 s or 153 s for two baseline protocols with different radial views corresponding to sampling factor of 1.0. CONCLUSION: This proposed method may allow accelerated free-breathing liver PDFF and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ mapping with reduced biases and variations.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Hígado , Imagen por Resonancia Magnética , Fantasmas de Imagen , Humanos , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos , Femenino , Masculino , Procesamiento de Imagen Asistido por Computador/métodos , Persona de Mediana Edad , Respiración , Algoritmos , Adulto , Reproducibilidad de los Resultados , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Movimiento (Física) , Tejido Adiposo/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Anciano
11.
Mov Disord ; 39(3): 585-595, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38247265

RESUMEN

BACKGROUND: Clinical trials of new drugs for tic disorders (TD) often fail to yield positive results. Placebo and nocebo responses play a vital role in interpreting the outcomes of randomized controlled trials (RCTs), yet these responses in RCTs of TD remain unexplored. OBJECTIVE: The aim was to assess the magnitude of placebo and nocebo responses in RCTs of pharmacological interventions for TD and identify influencing factors. METHODS: A systematic search of the Embase, Medline, Cochrane Central Register of Controlled Trials, and PsycINFO databases was conducted. Eligible studies were RCTs that compared active pharmacological agents with placebos. Placebo response was defined as the change from baseline in TD symptom severity in the placebo group, and nocebo response as the proportion experiencing adverse events (AEs) in this group. Subgroup analysis and meta-regression were performed to explore modifying factors. RESULTS: Twenty-four trials involving 2222 participants were included in this study. A substantial placebo response in TD symptom severity was identified, with a pooled effect size of -0.79 (95% confidence interval [CI] -0.99 to -0.59; I2 = 67%). Forty-four percent (95% CI 27% to 63%; I2 = 92%) of patients experienced AEs while taking inert pills. Sample size, study design, and randomization ratio were correlated with changes in placebo and nocebo responses. CONCLUSION: There were considerable placebo and nocebo responses in TD clinical trials. These results are of great relevance for the design of future trials and for clinical practice in TD. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration ID CRD42023388397. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Efecto Nocebo , Trastornos de Tic , Humanos , Efecto Placebo , Proyectos de Investigación , Trastornos de Tic/tratamiento farmacológico
12.
Am J Nephrol ; 55(1): 25-36, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37963441

RESUMEN

INTRODUCTION: Rituximab has been proven effective and safe in pediatric patients with frequently relapsing or steroid-dependent nephrotic syndrome (FR/SDNS). We aimed to analyze the efficacy and safety of rituximab in adult FR/SDNS patients with minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS). METHODS: A retrospective cohort study at three nephrology centers in China included adult FR/SDNS patients with biopsy-proven MCD or FSGS. Primary outcomes were relapse frequency and first relapse-free survival time. Adverse events were well recorded, and logistic regression analyses were used to investigate the risk factors of relapse. RESULTS: Eighty-one patients (age, 25.0 years; interquartile range, 20.0-40.5; 67% males; 82.7% MCD) received an average rituximab dose of 1,393.8 ± 618.7 mg/2 years during the 2-year follow-up period. The relapse frequency, calculated as the ratio of relapse times to follow-up years, significantly decreased after rituximab treatment (0.04 [0.00, 0.08] vs. 1.71 [1.00, 2.45], p < 0.001). The first relapse-free survival time was 16.7 ± 8.0 months. Fifty-seven patients (70.4%) achieved cessation of corticosteroids and immunosuppressants within 3 months after the first rituximab infusion. Adverse events were mostly mild, and no severe treatment-related adverse events were observed. Low serum albumin level before rituximab and high CD56+CD16+ natural killer cell count after rituximab were independent risk factors of relapse within 2 years after rituximab treatment. CONCLUSION: Rituximab was proven an effective and safe treatment option for adult FR/SDNS patients with MCD or FSGS in maintaining disease remission and minimizing corticosteroid exposure.


Asunto(s)
Glomeruloesclerosis Focal y Segmentaria , Nefrosis Lipoidea , Síndrome Nefrótico , Masculino , Adulto , Humanos , Niño , Femenino , Rituximab/efectos adversos , Glomeruloesclerosis Focal y Segmentaria/complicaciones , Glomeruloesclerosis Focal y Segmentaria/tratamiento farmacológico , Estudios Retrospectivos , Síndrome Nefrótico/tratamiento farmacológico , Síndrome Nefrótico/inducido químicamente , Nefrosis Lipoidea/tratamiento farmacológico , Nefrosis Lipoidea/inducido químicamente , Inmunosupresores/efectos adversos , Recurrencia , Enfermedad Crónica , Resultado del Tratamiento
13.
Nephrol Dial Transplant ; 39(3): 520-530, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-37667508

RESUMEN

BACKGROUND: The 2021 clinical guidelines of the Kidney Disease: Improving Global Outcomes emphasize the importance of the histological activity index (AI) in the management of lupus nephritis (LN). Patients with LN and a high AI have poor renal outcomes and high rates of nephritic relapse. In this study we constructed prediction models for the AI in LN. METHODS: The study population comprised 337 patients diagnosed with LN using kidney biopsy. The participants were randomly divided into training and testing cohorts. They were further divided into high-activity (AI >2) and low-activity (AI ≤2) groups. This study developed two clinical prediction models using logistic regression and least absolute shrinkage and selection operator (LASSO) analyses with laboratory test results collected at the time of kidney biopsy. The performance of models was assessed using 5-fold cross-validation and validated in the testing cohort. A nomogram for individual assessment was constructed based on the preferable model. RESULTS: Multivariate analysis showed that higher mean arterial pressure, lower estimated glomerular filtration rate, lower complement 3 level, higher urinary erythrocytes count and anti-double-stranded DNA seropositivity were independent risk factors for high histologic activity in LN. Both models performed well in the testing cohort regarding the discriminatory ability to identify patients with an AI >2. The average area under the curve of 5-fold cross-validation was 0.855 in the logistic model and 0.896 in the LASSO model. A webtool based on the LASSO model was created for clinicians to enter baseline clinical parameters to produce a probability score of an AI >2. CONCLUSIONS: The established nomogram provides a quantitative auxiliary tool for distinguishing LN patients with a high AI and helps physicians make clinical decisions in their comprehensive assessment.


Asunto(s)
Nefritis Lúpica , Humanos , Nefritis Lúpica/diagnóstico , Nefritis Lúpica/patología , Nomogramas , Riñón/patología , Tasa de Filtración Glomerular , Proyectos de Investigación
14.
Artículo en Inglés | MEDLINE | ID: mdl-38695863

RESUMEN

Human breast milk contains lactic acid bacteria (LAB), which have an important influence on the composition of the intestinal microbia of infants. In this study, one strain of an α-hemolytic species of the genus Streptococcus, IMAU99199T, isolated from the breast milk of a healthy nursing mother in Hohhot city PR China, was studied to characterise its taxonomic status using phenotypic and molecular taxonomic methods. The results indicated that it represented a member of the mitis-suis clade, pneumoniae subclade of the genus Streptococcus. It is a Gram-stain-positive, catalase-negative and oxidase-negative bacterium, and the cells are globular, paired or arranged in short chains. The results of a phylogenetic analysis of its 16S rRNA gene and two housekeeping genes (gyrB and rpoB) placed it in the genus Streptococcus. A phylogenetic tree based on 135 single-copy genes sequences indicated that IMAU99199T formed a closely related branch well separated from 'Streptococcus humanilactis' IMAU99125, 'Streptococcus bouchesdurhonensis' Marseille Q6994, Streptococcus mitis NCTC 12261T, 'Streptococcus vulneris' DM3B3, Streptococcus toyakuensis TP1632T, Streptococcus pseudopneumoniae ATCC BAA-960T and Streptococcus pneumoniae NCTC 7465T. IMAU99199T and 'S. humanilactis' IMAU99125 had the highest average nucleotide identity (93.7 %) and digital DNA-DNA hybridisation (55.3 %) values, which were below the accepted thresholds for novel species. The DNA G+C content of the draft genome of IMAU99199T was 39.8 %. The main cellular fatty acids components of IMAU99199T were C16 : 0 and C16 : 1ω7. It grew at a temperature range of 25-45 °C (the optimum growth temperature was 37 °C) and a pH range of 5.0-8.0 (the optimum growth pH was 7.0). These data indicate that strain IMAU99199T represents a novel species in the genus Streptococcus, for which the name Streptococcus hohhotensis sp. nov. is proposed. The type strain is IMAU99199T (=GDMCC 1.1874T=KCTC 21155T).


Asunto(s)
Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano , Ácidos Grasos , Leche Humana , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Streptococcus , ARN Ribosómico 16S/genética , Humanos , Femenino , China , ADN Bacteriano/genética , Leche Humana/microbiología , Streptococcus/genética , Streptococcus/aislamiento & purificación , Streptococcus/clasificación , Ácidos Grasos/análisis , Hibridación de Ácido Nucleico , Genes Bacterianos
15.
Mol Cell ; 64(4): 803-814, 2016 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-27818144

RESUMEN

Mitochondrial p53 is involved in apoptosis and tumor suppression. However, its regulation is not well studied. Here, we show that TRAF6 E3 ligase is a crucial factor to restrict mitochondrial translocation of p53 and spontaneous apoptosis by promoting K63-linked ubiquitination of p53 at K24 in cytosol, and such ubiquitination limits the interaction between p53 and MCL-1/BAK. Genotoxic stress reduces this ubiquitination in cytosol by S13/T330 phosphorylation-dependent translocation of TRAF6 from cytosol to nucleus, where TRAF6 also facilitates the K63-linked ubiquitination of nuclear p53 and its transactivation by recruiting p300 for p53 acetylation. Functionally, K63-linked ubiquitination of p53 compromised p53-mediated apoptosis and tumor suppression. Colorectal cancer samples with WT p53 reveal that TRAF6 overexpression negatively correlates with apoptosis and predicts poor response to chemotherapy and radiotherapy. Together, our study identifies TRAF6 as a critical gatekeeper to restrict p53 mitochondrial translocation, and such mechanism may contribute to tumor development and drug resistance.


Asunto(s)
Neoplasias del Colon/genética , Regulación Neoplásica de la Expresión Génica , Mitocondrias/metabolismo , Factor 6 Asociado a Receptor de TNF/genética , Proteína p53 Supresora de Tumor/genética , Animales , Antineoplásicos/uso terapéutico , Apoptosis/genética , Línea Celular Tumoral , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/mortalidad , Neoplasias del Colon/patología , Citosol/efectos de los fármacos , Citosol/metabolismo , Proteína p300 Asociada a E1A/genética , Proteína p300 Asociada a E1A/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular , Lisina/metabolismo , Ratones , Mitocondrias/efectos de los fármacos , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/genética , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Trasplante de Neoplasias , Transporte de Proteínas , Transducción de Señal , Sulfonamidas/farmacología , Análisis de Supervivencia , Factor 6 Asociado a Receptor de TNF/metabolismo , Proteína p53 Supresora de Tumor/antagonistas & inhibidores , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitinación , Ensayos Antitumor por Modelo de Xenoinjerto , Proteína Destructora del Antagonista Homólogo bcl-2/genética , Proteína Destructora del Antagonista Homólogo bcl-2/metabolismo
16.
Med Sci Monit ; 30: e943049, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38553816

RESUMEN

BACKGROUND Triple-negative breast cancer (TNBC) is a distinct subtype of breast cancer, accounting for 12-18% of all breast cancer cases. It exhibits high heterogeneity and aggressiveness, resulting in a poorer prognosis with a high risk of early recurrence and metastasis. Due to the lack of expression of estrogen receptors (ER), progesterone receptors (PR), and human epidermal growth factor receptor 2 (HER2), as well as insensitivity to endocrine therapy, determining a standard treatment for TNBC is challenging. The identification of potential prognostic biomarkers is crucial for developing personalized treatment strategies for patients. MATERIAL AND METHODS Our study investigated the potential value of HSP90a in TNBC prognosis. A retrospective analysis was conducted on 127 TNBC patients and 127 Healthy controls from March 1, 2019 to July 31, 2022. Venous blood was collected and tested for HSP90alpha, CEA, CA199, and CA125, and we recorded the clinical characteristics of the patients, including age, BMI, alcohol consumption status, surgical history, CEA level, CA199 level, CA125 level, HSP90alpha level, tumor size, distant metastases, lymph node metastasis, and TNM stage. Univariate and multivariate methods were used to screen independent risk factors for progression-free survival (PFS) and overall survival (OS). RESULTS HSP90alpha is not only upregulated in TNBC but is also highly correlated with lymph node metastasis and TNM stage. The results of multivariate analysis showed that distant metastasis, TNM stage and HSP90a level were independent factors associated with PFS. BMI, tumor size, TNM stage, surgical history, and HSP90a level were independent factors influencing OS. CONCLUSIONS Our research findings demonstrate a significant association between high HSP90alpha expression and adverse clinical features, suggesting a poorer prognosis for TNBC patients.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Mama Triple Negativas , Humanos , Femenino , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama/patología , Estudios Retrospectivos , Metástasis Linfática , Pronóstico , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Biomarcadores de Tumor/metabolismo
17.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33558418

RESUMEN

The expansion of anatomically modern humans (AMHs) from Africa around 65,000 to 45,000 y ago (ca. 65 to 45 ka) led to the establishment of present-day non-African populations. Some paleoanthropologists have argued that fossil discoveries from Huanglong, Zhiren, Luna, and Fuyan caves in southern China indicate one or more prior dispersals, perhaps as early as ca. 120 ka. We investigated the age of the human remains from three of these localities and two additional early AMH sites (Yangjiapo and Sanyou caves, Hubei) by combining ancient DNA (aDNA) analysis with a multimethod geological dating strategy. Although U-Th dating of capping flowstones suggested they lie within the range ca. 168 to 70 ka, analyses of aDNA and direct AMS 14C dating on human teeth from Fuyan and Yangjiapo caves showed they derive from the Holocene. OSL dating of sediments and AMS 14C analysis of mammal teeth and charcoal also demonstrated major discrepancies from the flowstone ages; the difference between them being an order of magnitude or more at most of these localities. Our work highlights the surprisingly complex depositional history recorded at these subtropical caves which involved one or more episodes of erosion and redeposition or intrusion as recently as the late Holocene. In light of our findings, the first appearance datum for AMHs in southern China should probably lie within the timeframe set by molecular data of ca. 50 to 45 ka.


Asunto(s)
Arqueología , Cuevas/química , ADN Antiguo/análisis , Fósiles , Sedimentos Geológicos/análisis , Migración Humana/historia , Datación Radiométrica/métodos , China , Historia Antigua , Humanos
18.
Ecotoxicol Environ Saf ; 279: 116461, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38763051

RESUMEN

Polystyrene nanoplastics (PS-NPs) have been reported to accumulate in the testes and constitute a new threat to reproductive health. However, the exact effects of PS-NPs exposure on testicular cells and the underlying mechanisms remain largely unknown. The C57BL/6 male mice were orally administered with PS-NPs (80 nm) at different dosages (0, 10, and 40 mg/kg/day) for 60 days, and GC-1 cells were treated with PS-NPs in this study. Enlarged seminiferous tubule lumens and a loose and vacuolated layer of spermatogenic cells were observed in PS-NPs-exposed mice. Spermatogenic cells which may be one of the target cells for this reproductive damage, were decreased in the mice from PS-NPs group. PS-NPs caused spermatogenic cells to undergo senescence, manifested as elevated SA-ß-galactosidase activity and activated senescence-related signaling p53-p21/Rb-p16 pathways, and induced cell cycle arrest. Mechanistically, Gene Ontology (GO) enrichment suggested the key role of reactive oxygen species (ROS) in PS-NPs-induced spermatogenic cell senescence, and this result was confirmed by measuring ROS levels. Moreover, ROS inhibition partially attenuated the senescence phenotype of spermatogenic cells and DNA damage. Using the male health atlas (MHA) database, Sirt1 was filtrated as the critical molecule in the regulation of testicular senescence. PS-NPs induced overexpression of the main ROS generator Nox2, downregulated Sirt1, increased p53 and acetylated p53 in vivo and in vitro, whereas these disturbances were partially restored by pterostilbene. In addition, pterostilbene intervention significantly alleviated the PS-NPs-induced spermatogenic cell senescence and attenuated ROS burst. Collectively, our study reveals that PS-NPs exposure can trigger spermatogenic cell senescence mediated by p53-p21/Rb-p16 signaling by regulating the Sirt1/ROS axis. Importantly, pterostilbene intervention may be a promising strategy to alleviate this damage.


Asunto(s)
Senescencia Celular , Ratones Endogámicos C57BL , Poliestirenos , Especies Reactivas de Oxígeno , Sirtuina 1 , Animales , Masculino , Sirtuina 1/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Senescencia Celular/efectos de los fármacos , Ratones , Poliestirenos/toxicidad , Testículo/efectos de los fármacos , Testículo/patología , Espermatogénesis/efectos de los fármacos , Nanopartículas/toxicidad , Daño del ADN , Transducción de Señal/efectos de los fármacos
19.
J Integr Neurosci ; 23(1): 20, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38287844

RESUMEN

More than half of the patients with autism spectrum disorder (ASD) have gastrointestinal (GI) comorbidities, such as constipation, indigestion, abdominal pain, and diarrhea. Recent studies suggest prescribing probiotics and prebiotics in ASD could relieve GI disturbances and behavioral issues. This narrative review generalizes the research progress on probiotic and prebiotic therapies for ASD over the past 5 years and further discusses the underlying mechanisms of interaction between probiotics and prebiotics with ASD. Preliminary evidence has demonstrated the beneficial effects of probiotics and prebiotics on GI problems, autism-related behavioral disorders, and gut microbiome composition; the mechanism of probiotics and prebiotics in the treatment of ASD is mediated through inflammatory signaling pathways, metabolic pathways, neuronal signaling pathways, and the involvement of the vagus nerve. However, the results are inconclusive and mainly generated by animal experiments. Overall, the present review recommends further standardization of clinical studies to draw more robust evidence for prescribing probiotics and prebiotics in ASD.


Asunto(s)
Trastorno del Espectro Autista , Enfermedades Gastrointestinales , Microbioma Gastrointestinal , Probióticos , Animales , Humanos , Prebióticos , Trastorno del Espectro Autista/tratamiento farmacológico
20.
Chem Biodivers ; 21(2): e202301703, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38055204

RESUMEN

Three undescribed limonoids (1-3), named aglaians G-I, and one new natural product azedaralide (4), together with nine known analogues (5-13) were isolated from the branches and leaves of Aglaia lawii by RP C18 column, silica gel column, Sephadex LH-20 column chromatography and preparative HPLC. The structures of the new compounds were elucidated by IR, HRESIMS, 1D, 2D NMR, electronic circular dichroism (ECD) calculations and X-ray crystallography diffraction analysis. The results of bioassay showed that the compound 12 exhibited potential inhibitory activity against six human tumor cell lines (MDA-MB-231, MCF-7, Ln-cap, A549, HeLa and HepG-2) with IC50 values as 8.0-18.6 µM.


Asunto(s)
Aglaia , Antineoplásicos , Limoninas , Humanos , Aglaia/química , Limoninas/farmacología , Limoninas/química , Estructura Molecular , Línea Celular Tumoral
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