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1.
Nucleic Acids Res ; 51(14): 7376-7391, 2023 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-37377435

RESUMEN

53BP1 is primarily known as a key regulator in DNA double-strand break (DSB) repair. However, the mechanism of DSB-triggered cohesin modification-modulated chromatin structure on the recruitment of 53BP1 remains largely elusive. Here, we identified acetyltransferase ESCO2 as a regulator for DSB-induced cohesin-dependent chromatin structure dynamics, which promotes 53BP1 recruitment. Mechanistically, in response to DNA damage, ATM phosphorylates ESCO2 S196 and T233. MDC1 recognizes phosphorylated ESCO2 and recruits ESCO2 to DSB sites. ESCO2-mediated acetylation of SMC3 stabilizes cohesin complex conformation and regulates the chromatin structure at DSB breaks, which is essential for the recruitment of 53BP1 and the formation of 53BP1 microdomains. Furthermore, depletion of ESCO2 in both colorectal cancer cells and xenografted nude mice sensitizes cancer cells to chemotherapeutic drugs. Collectively, our results reveal a molecular mechanism for the ATM-ESCO2-SMC3 axis in DSB repair and genome integrity maintenance with a vital role in chemotherapy response in colorectal cancer.


Asunto(s)
Proteínas de Ciclo Celular , Proteína 1 de Unión al Supresor Tumoral P53 , Animales , Ratones , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Cromatina , Neoplasias Colorrectales/metabolismo , Daño del ADN , Reparación del ADN , Ratones Desnudos , Proteína 1 de Unión al Supresor Tumoral P53/genética , Humanos , Línea Celular Tumoral , Cohesinas
2.
Chin J Traumatol ; 27(3): 168-172, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38262890

RESUMEN

PURPOSE: To identify the risk factors for training-related lower extremity muscle injuries in young males by a non-invasive method of body composition analysis. METHODS: A total of 282 healthy young male volunteers aged 18 - 20 years participated in this cohort study. Injury location, degree, and injury rate were adjusted by a questionnaire based on the overuse injury assessment methods used in epidemiological studies of sports injuries. The occurrence of training injuries is monitored and diagnosed by physicians and treated accordingly. The body composition was measured using the BodyStat QuadScan 4000 multifrequency Bio-impedance system at 5, 50, 100 and 200 kHz to obtain 4 impedance values. The Shapiro-Wilk test was used to check whether the data conformed to a normal distribution. Data of normal distribution were shown as mean ± SD and analyzed by t-test, while those of non-normal distribution were shown as median (Q1, Q3) and analyzed by Wilcoxon rank sum test. The receiver operator characteristic curve and logistic regression analysis were performed to investigate risk factors for developing training-related lower extremity injuries and accuracy. RESULTS: Among the 282 subjects, 78 (27.7%) developed training injuries. Lower extremity training injuries revealed the highest incidence, accounting for 23.4% (66 cases). These patients showed higher percentages of lean body mass (p = 0.001), total body water (TBW, p = 0.006), extracellular water (p = 0.020) and intracellular water (p = 0.010) as well as a larger ratio of basal metabolic rate/total weight (p = 0.006), compared with those without lower extremity muscle injuries. On the contrary, the percentage of body fat (p = 0.001) and body fat mass index (p = 0.002) were lower. Logistic regression analysis showed that TBW percentage > 65.35% (p = 0.050, odds ratio = 3.114) and 3rd space water > 0.95% (p = 0.045, odds ratio = 2.342) were independent risk factors for lower extremity muscle injuries. CONCLUSION: TBW percentage and 3rd space water measured with bio-impedance method are potential risk factors for predicting the incidence of lower extremity muscle injuries in young males following training.


Asunto(s)
Agua Corporal , Extremidad Inferior , Músculo Esquelético , Humanos , Masculino , Factores de Riesgo , Adulto Joven , Adolescente , Extremidad Inferior/lesiones , Músculo Esquelético/lesiones , Traumatismos en Atletas/epidemiología , Composición Corporal , Estudios de Cohortes
3.
J Clin Pharm Ther ; 47(12): 2245-2254, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36345158

RESUMEN

WHAT IS KNOWN AND OBJECTIVES: Voriconazole has a complex pharmacokinetic profile and exhibits different pharmacokinetic characteristics in adults and children. Nevertheless, few studies have been conducted on the population pharmacokinetics (PPK) of voriconazole in children with haematological malignancies. This study aims to build a PPK model and propose a suitable voriconazole treatment scheme for children with haematological malignancies. METHODS: We retrospectively collected 146 samples from 67 children aged from 1.08 to 17.92 years. The PPK model was established using nonlinear mixed effects modelling (NONMEM). Dosage simulations were conducted on the basis of the final model's covariates. RESULTS AND DISCUSSION: Data were fully characterized by a one-compartment model with first-order absorption and elimination. The weight (WT), CYP2C19 phenotype, and Albumin (ALB) were notable covariates for clearance (CL). The typical values of CL, the volume of distribution (V), and oral bioavailability (F) were 2.29 L/h, 76 L, and 0.902, respectively. The proposed doses for different CYP2C19 genotypes were presented in this ranking: EM (extensive metabolizer) > IM (intermediate metabolizer) > PM (poor metabolizer). Furthermore, higher dosages for light WT patients were recommended while lower ALB levels required lower doses. The probability of achieving the target (PTA) for the recommended doses ranged from 72.2% to 99%. WHAT IS NEW AND CONCLUSION: We successfully built a voriconazole PPK model for children with hematologic malignancies. Dosing regimens were developed for different patients based on the final model, which could enhance the rational use of voriconazole in children with haematological malignancies.


Asunto(s)
Antifúngicos , Neoplasias Hematológicas , Niño , Humanos , Voriconazol/uso terapéutico , Citocromo P-450 CYP2C19/genética , Estudios Retrospectivos , Neoplasias Hematológicas/tratamiento farmacológico
4.
Ann Pharmacother ; 55(4): 440-451, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32924532

RESUMEN

BACKGROUND: Hematopoietic stem cell transplantation (HSCT) is an effective treatment for hematological disorders. Tacrolimus is widely used after HSCT, but it has highly interindividual variable pharmacokinetics. Population pharmacokinetics (PPK) researches of tacrolimus in children with ß-thalassemia major (ß-TM) undergoing HSCT are insufficient. OBJECTIVE: To establish a PPK model of tacrolimus in children with ß-TM and optimize initial dosing regimen for achieving target concentration of 5 to 15 ng/mL. METHODS: Data on patients aged <18 years were retrospectively collected from January 2017 to December 2018. PPK analysis and Monte Carlo simulations were performed using nonlinear mixed-effects modeling. RESULTS: A data set of 55 patients with 332 concentrations was included. A 2-compartment model could best describe the pharmacokinetics of tacrolimus. The body surface area and gender were significant covariates in the final model. The typical value of clearance, the distribution volume of the central room, the distribution volume of the peripheral room, and the intercompartmental clearance were 5.05L/h, 4.33L, 155L, and 6.22L/h, respectively. The optimal initial dosing regimen of 0.03, 0.04, 0.05, 0.06, and 0.10 mg/kg were appropriate for female children with a weight (WT) of 50 to 10 kg. The regimen of 0.04, 0.05, 0.06, 0.07, and 0.12 mg/kg is suitable for male children with a WT of 50 to 10 kg. The probability of target attainment (PTA) of each regimen reached 91%. CONCLUSION AND RELEVANCE: A stable PPK model of tacrolimus was established. The proposed dosage regimen reached a good PTA, which could provide a reference for tacrolimus therapy.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/métodos , Inmunosupresores/administración & dosificación , Modelos Biológicos , Tacrolimus/administración & dosificación , Talasemia beta/terapia , Adolescente , Niño , Preescolar , Cálculo de Dosificación de Drogas , Femenino , Humanos , Inmunosupresores/farmacocinética , Masculino , Método de Montecarlo , Estudios Retrospectivos , Tacrolimus/farmacocinética , Talasemia beta/sangre
5.
J Clin Pharm Ther ; 46(3): 820-831, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33751618

RESUMEN

WHAT IS KNOWN AND OBJECTIVES: Various population pharmacokinetic (PopPK) models for vancomycin in children and adolescents have been constructed to optimize the therapeutic regimen of vancomycin. However, little is known about their predictive performance when extrapolated to different clinical centres. Therefore, the aim of this study was to externally validate the predictability of vancomycin PopPK model when extrapolated to different clinical centres and verify its applicability in an independent data set. METHODS: The published models were screened from the literature and evaluated using an external data set of a total of 451 blood concentrations of vancomycin measured in 220 Chinese paediatric patients. Prediction- and simulation-based diagnostics and Bayesian forecasting were performed to evaluate the predictive performance of the models. RESULTS: Ten published PopPK models were assessed. Prediction-based diagnostics showed that none of the investigated models met all the standards (median prediction error (MDPE) ≤ ±20%, median absolute prediction error (MAPE) ≤30%, PE% within ±20% (F20 ) ≥35% and PE% within ±30% (F30 ) ≥50%), indicating unsatisfactory predictability. In simulation-based diagnostics, both the visual predictive checks (VPC) and the normalized prediction distribution error (NPDE) indicated misspecification in all models. Bayesian forecasting results showed that the accuracy and precision of individual predictions could be significantly improved with one or two prior observations, but frequent monitoring might not be necessary in the clinic, since Bayesian forecasting identified that greater number of samples did not significantly improve the predictability. Model 3 established by Moffett et al showed better predictability than other models. WHAT IS NEW AND CONCLUSION: The 10 published models performed unsatisfactorily in prediction- and simulation-based diagnostics; none of the published models was suitable for designing the initial dosing regimens of vancomycin. Pharmacokinetic characteristics and covariates, such as weight, renal function, age and underlying disease should be taken into account when extrapolating the vancomycin model. Bayesian forecasting combined with therapeutic drug monitoring based on model 3 can be used to adjust vancomycin dosing regimens.


Asunto(s)
Antibacterianos/farmacocinética , Modelos Biológicos , Vancomicina/farmacocinética , Adolescente , Factores de Edad , Teorema de Bayes , Peso Corporal , Niño , Preescolar , China , Simulación por Computador , Femenino , Humanos , Pruebas de Función Renal , Masculino , Reproducibilidad de los Resultados
6.
Water Sci Technol ; 83(1): 198-211, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33460418

RESUMEN

Blended organic copolymer (or homopolymer) and inorganic nanoparticles have been widely used (separately or simultaneously) for optimizing membrane pore structure and surface functionality. However, the prepared membranes suffer from degraded stability and insufficient integrity due to the high solubility or incompatibility of the blending additives. In this work, an organic-inorganic nanocomposite (i.e., PLA-TiO2) was designed, and employed for PSF membrane preparation. The Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis confirmed that bidentate chelating dominated the bonding mechanism between PLA and TiO2. The resultant PSF/PLA-TiO2 membranes possessed a highly porous surface with narrowed pore size distribution, demonstrating the strong pore forming ability of PLA-TiO2 for membrane preparations. Moreover, owing to the distinct inorganic-organic molecular conformation, the PLA-TiO2 exhibited enhanced stability and dispersibility within the PSF substance, which endowed the membrane with long-acting hydrophilicity and UV responsiveness. Given the UV responsiveness that is introduced by PLA-TiO2, UV-assisted strategies (UV-F and UV-C) were designed to further mitigate membrane fouling. The fouling analysis indicated that both reversible fouling and irreversible fouling were reduced in the UV-C process, signifying the synergistic effect between photocatalysis and hydraulics in membrane fouling mitigation. The enhanced membrane performance and the efficient preparation process highlight the potential of PLA-TiO2 in membrane modifications.


Asunto(s)
Nanocompuestos , Polímeros , Poliésteres , Sulfonas , Titanio
7.
Chin J Traumatol ; 24(3): 125-131, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33840582

RESUMEN

With the widespread adoption of advanced tourniquets, the mortality rate of limb wound hemorrhage has decreased significantly, and non-compressible torso hemorrhage has gradually occupied the leading position of potentially preventable death, both in military and civilian circumstances. With the emergence of novel hemostatic devices and materials, strategies for the management of non-compressible torso hemorrhage have changed significantly. This review summarizes the current treatment strategies and types of equipment for non-compressible torso hemorrhage and suggests future research directions, hoping to provide a comprehensive review for the medical personnel and researchers engaging in this field.


Asunto(s)
Hemorragia , Hemostáticos , Hemorragia/etiología , Hemorragia/terapia , Humanos , Torso
8.
J Biol Chem ; 294(42): 15395-15407, 2019 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-31462535

RESUMEN

The transcription factor signal transducer and activator of transcription 3 (STAT3) plays a central role in cell survival and function. STAT3 has been demonstrated to participate in the maintenance of bone homeostasis in osteoblasts, but its role in osteoclasts in vivo remains poorly defined. Here, we generated a conditional knockout mouse model in which Stat3 was deleted in osteoclasts using a cathepsin K-Cre (Ctsk-Cre) driver. We observed that osteoclast-specific Stat3 deficiency caused increased bone mass in mice, which we attributed to impaired bone catabolism by osteoclasts. Stat3-deficient bone marrow macrophages (BMMs) showed decreased expression of nuclear factor of activated T cells, cytoplasm 1 (NFATc1), and reduced osteoclast differentiation determined by decreases in osteoclast number, tartrate-resistant acid phosphatase activity, and expression of osteoclast marker genes. Enforced expression of NFATc1 in Stat3-deficient BMMs rescued the impaired osteoclast differentiation. Mechanistically, we revealed that STAT3 could drive the transcription of NFATc1 by binding to its promoter. Furthermore, preventing STAT3 activation by using an inhibitor of upstream phosphorylases, AG490, also impaired osteoclast differentiation and formation in a similar way as gene deletion of Stat3 In summary, our data provide the first evidence that STAT3 is significant in osteoclast differentiation and bone homeostasis in vivo, and it may be identified as a potential pharmacological target for the treatment of bone metabolic diseases through regulation of osteoclast activity.


Asunto(s)
Huesos/metabolismo , Factores de Transcripción NFATC/metabolismo , Osteoclastos/metabolismo , Osteogénesis , Factor de Transcripción STAT3/metabolismo , Animales , Femenino , Regulación de la Expresión Génica , Homeostasis , Humanos , Macrófagos/citología , Macrófagos/metabolismo , Masculino , Ratones , Ratones Noqueados , Factores de Transcripción NFATC/genética , Osteoclastos/citología , Factor de Transcripción STAT3/genética , Transducción de Señal
9.
Ann Rheum Dis ; 79(1): 112-122, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31662319

RESUMEN

OBJECTIVES: This study aims to investigate the role and mechanism of FGFR3 in macrophages and their biological effects on the pathology of arthritis. METHODS: Mice with conditional knockout of FGFR3 in myeloid cells (R3cKO) were generated. Gait behaviours of the mice were monitored at different ages. Spontaneous synovial joint destruction was evaluated by digital radiographic imaging and µCT analysis; changes of articular cartilage and synovitis were determined by histological analysis. The recruitment of macrophages in the synovium was examined by immunostaining and monocyte trafficking assay. RNA-seq analysis, Western blotting and chemotaxis experiment were performed on control and FGFR3-deficient macrophages. The peripheral blood from non-osteoarthritis (OA) donors and patients with OA were analysed. Mice were treated with neutralising antibody against CXCR7 to investigate the role of CXCR7 in arthritis. RESULTS: R3cKO mice but not control mice developed spontaneous cartilage destruction in multiple synovial joints at the age of 13 months. Moreover, the synovitis and macrophage accumulation were observed in the joints of 9-month-old R3cKO mice when the articular cartilage was not grossly destructed. FGFR3 deficiency in myeloid cells also aggravated joint destruction in DMM mouse model. Mechanically, FGFR3 deficiency promoted macrophage chemotaxis partly through activation of NF-κB/CXCR7 pathway. Inhibition of CXCR7 could significantly reverse FGFR3-deficiency-enhanced macrophage chemotaxis and the arthritic phenotype in R3cKO mice. CONCLUSIONS: Our study identifies the role of FGFR3 in synovial macrophage recruitment and synovitis, which provides a new insight into the pathological mechanisms of inflammation-related arthritis.


Asunto(s)
Cartílago Articular/patología , Quimiocina CXCL12/metabolismo , Macrófagos/metabolismo , Osteoartritis/genética , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/genética , Receptores CXCR/genética , Sinovitis/genética , Animales , Quimiotaxis/genética , Marcha , Regulación de la Expresión Génica , Humanos , Articulaciones/metabolismo , Articulaciones/patología , Ratones , Ratones Noqueados , Monocitos/metabolismo , Células Mieloides , FN-kappa B/metabolismo , Osteoartritis/metabolismo , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/metabolismo , Receptores CXCR/metabolismo , Membrana Sinovial/metabolismo , Membrana Sinovial/patología , Sinovitis/patología
10.
Bioorg Chem ; 94: 103366, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31640932

RESUMEN

Our recently successful identification of benzoic acid-based DPP-4 inhibitors spurs the further quest for in-depth structure-activity relationships (SAR) study in S2' site DPP-4. Thus novel benzamide fragments were designed to target the S2' site to compromise lipophilicity and improve oral activity. Exploring SAR by introduction of a variety of amide and halogen on benzene ring led to identification of several compounds, exerting moderated to excellent DPP-4 activities, in which 4'-chlorine substituted methyl amide 17g showed most potent DPP-4 activity with the IC50 value of 1.6 nM. Its activity was superior to reference alogliptin. Docking study ideally verified and interpreted the obtained SAR of designed compounds. As a continuation, DPP-8/9 assays revealed the designed compounds exhibited good selectivity over DPP-8 and DPP-9. Subsequent cell-based test indicated compound 17g displayed low toxicity toward the LO2 cell line up to 100 µM. In vivo evaluation showed compound 17g robustly improved the glucose tolerance in normal mice. Importantly, 17g exhibited reasonable pharmacokinetic (PK) profiles for oral delivery. Overall, compound 17g has the potential to a safe and efficacious DPP-4 inhibitor for T2DM treatment.


Asunto(s)
Benzamidas/farmacología , Diabetes Mellitus Experimental/tratamiento farmacológico , Dipeptidil Peptidasa 4/metabolismo , Inhibidores de la Dipeptidil-Peptidasa IV/farmacología , Hipoglucemiantes/farmacología , Animales , Benzamidas/síntesis química , Benzamidas/química , Glucemia/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Diabetes Mellitus Experimental/metabolismo , Inhibidores de la Dipeptidil-Peptidasa IV/síntesis química , Inhibidores de la Dipeptidil-Peptidasa IV/química , Relación Dosis-Respuesta a Droga , Prueba de Tolerancia a la Glucosa , Humanos , Hipoglucemiantes/síntesis química , Hipoglucemiantes/química , Masculino , Ratones , Ratones Endogámicos , Modelos Moleculares , Estructura Molecular , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad
11.
J Biol Chem ; 293(23): 8761-8774, 2018 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-29691281

RESUMEN

Temporomandibular joint osteoarthritis (TMJ OA) is a common degenerative disease with few effective disease-modifying treatments in the clinic. Fibroblast growth factor (FGF) signaling is implicated in articular cartilage homeostasis, but the functional roles of FGFR1 in TMJ OA remain largely unknown. In this study, we report that deletion of Fgfr1 in TMJ chondrocytes delayed TMJ OA progression in the age-associated spontaneous OA model and the abnormal dental occlusion OA model. Immunohistochemical staining revealed that Fgfr1 deficiency decreased the expressions of MMP13 (matrix metalloproteinase-13), ADAMTS5 (a disintegrin and metalloproteinase with thrombospondin motifs 5), and COL10A1 but increased aggrecan expression level in two TMJ OA models. Furthermore, our data show that inactivation of FGFR1 signaling may promote autophagic activity in TMJ. FGFR1 inhibitor decreased the expressions of Mmp13, Adamts5, and Runx2 in IL-1ß-stimulated condylar chondrocytes, whereas autophagy inhibitors abrogated the protective effects of the FGFR1 inhibitor. Thus, our study indicates inactivated FGFR1 signaling ameliorates TMJ OA progression partially by promoting autophagic activity. Manipulation of this signaling may be a potential therapeutic approach to modify TMJ OA.


Asunto(s)
Autofagia , Condrocitos/patología , Eliminación de Gen , Osteoartritis/genética , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/genética , Articulación Temporomandibular/patología , Animales , Cartílago Articular/metabolismo , Cartílago Articular/patología , Condrocitos/metabolismo , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Osteoartritis/patología , Articulación Temporomandibular/metabolismo
12.
Bioorg Med Chem ; 27(4): 644-654, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30642693

RESUMEN

Dipeptidyl Peptidase-IV (DPP-4) is a validated therapeutic target for type 2 diabetes. Aiming to interact with both residues Try629 and Lys554 in S2' site, a series of novel uracil derivatives 1a-l and 2a-i incorporating benzoic acid moieties at the N3 position were designed and evaluated for their DPP-4 inhibitory activity. Structure-activity relationships (SAR) study led to the identification of the optimal compound 2b as a potent and selective DPP-4 inhibitor (IC50 = 1.7 nM). Docking study revealed the additional salt bridge formed between the carboxylic acid and primary amine of Lys554 has a key role in the enhancement of the activity. Furthermore, compound 2b exhibited no cytotoxicity in human hepatocyte LO2 cells up to 50 µM. Subsequent in vivo evaluations revealed that the ester of 2b robustly improves the glucose tolerance in normal mice. The overall results have shown that compound 2b has the potential to a safe and efficacious treatment for T2DM.


Asunto(s)
Benzoatos/uso terapéutico , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Hipoglucemiantes/farmacología , Uracilo/análogos & derivados , Uracilo/uso terapéutico , Animales , Benzoatos/síntesis química , Benzoatos/toxicidad , Dominio Catalítico , Línea Celular , Dipeptidil Peptidasa 4/química , Inhibidores de la Dipeptidil-Peptidasa IV/síntesis química , Inhibidores de la Dipeptidil-Peptidasa IV/toxicidad , Diseño de Fármacos , Prueba de Tolerancia a la Glucosa , Humanos , Hipoglucemiantes/síntesis química , Hipoglucemiantes/toxicidad , Masculino , Ratones , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad , Uracilo/toxicidad
13.
J Biol Chem ; 292(1): 196-204, 2017 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-27879318

RESUMEN

Mammalian target of rapamycin complex 1 (mTORC1) is involved in anabolic metabolism in both osteoblasts and chondrocytes, but the role of mTORC1 in osteoclast biology in vivo remains to be elucidated. In this study, we showed that deletion of regulatory-associated protein of mTOR (Raptor) in osteoclasts led to an increase in bone mass with decreased bone resorption. Raptor-deficient bone marrow-derived macrophages exhibited lower mTORC1-S6K1 signaling and retarded osteoclast differentiation, as determined by the number of osteoclasts, tartrate-resistant acid phosphatase activity, and expression of osteoclast-specific genes. Enforced expression of constitutively active S6K1 rescued the impaired osteoclast differentiation in Raptor-deficient bone marrow-derived macrophages. Furthermore, pharmacological inhibition of mTORC1 signaling by rapamycin could also inhibit osteoclast differentiation and osteoclast-specific gene expression. Taken together, our findings demonstrate that mTORC1 plays a key role in the network of catabolic bone resorption in osteoclasts and may serve as a potential pharmacological target for the regulation of osteoclast activity in bone metabolic disorders.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/antagonistas & inhibidores , Huesos/patología , Diferenciación Celular , Complejos Multiproteicos/antagonistas & inhibidores , Osteoclastos/patología , Osteogénesis/fisiología , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Proteínas Adaptadoras Transductoras de Señales/fisiología , Animales , Densidad Ósea , Huesos/metabolismo , Células Cultivadas , Macrófagos/metabolismo , Macrófagos/patología , Masculino , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Ratones Noqueados , Complejos Multiproteicos/genética , Complejos Multiproteicos/metabolismo , Osteoclastos/metabolismo , Fosforilación , Proteína Reguladora Asociada a mTOR , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo
14.
PLoS Genet ; 11(6): e1005214, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26091072

RESUMEN

Most cartilaginous tumors are formed during skeletal development in locations adjacent to growth plates, suggesting that they arise from disordered endochondral bone growth. Fibroblast growth factor receptor (FGFR)3 signaling plays essential roles in this process; however, the role of FGFR3 in cartilaginous tumorigenesis is not known. In this study, we found that postnatal chondrocyte-specific Fgfr3 deletion induced multiple chondroma-like lesions, including enchondromas and osteochondromas, adjacent to disordered growth plates. The lesions showed decreased extracellular signal-regulated kinase (ERK) activity and increased Indian hedgehog (IHH) expression. The same was observed in Fgfr3-deficient primary chondrocytes, in which treatment with a mitogen-activated protein kinase (MEK) inhibitor increased Ihh expression. Importantly, treatment with an inhibitor of IHH signaling reduced the occurrence of chondroma-like lesions in Fgfr3-deficient mice. This is the first study reporting that the loss of Fgfr3 function leads to the formation of chondroma-like lesions via downregulation of MEK/ERK signaling and upregulation of IHH, suggesting that FGFR3 has a tumor suppressor-like function in chondrogenesis.


Asunto(s)
Condroma/metabolismo , Proteínas Hedgehog/metabolismo , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/metabolismo , Regulación hacia Arriba , Animales , Línea Celular , Células Cultivadas , Condrocitos/metabolismo , Condroma/genética , Proteínas Hedgehog/genética , Sistema de Señalización de MAP Quinasas , Ratones , Ratones Endogámicos C57BL , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/deficiencia , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/genética
15.
J Craniofac Surg ; 29(5): 1216-1219, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29498973

RESUMEN

OBJECTIVE: The aim of the study was to study the specific morphological features of alveolar bone and compare it to femoral bone in rats. METHODS: Twelve 3-month-old nonpregnant female Sprague-Dawley rats were used in the present study. The left maxillae and femurs of 6 rats were used for micro-computed tomography (micro-CT) scanning. The trabecular bone of the distal femur and the interradicular alveolar bone of the maxillary first molar were reconstructed and analyzed. Another 6 rats were used for histological analysis of trabecular bone and alveolar bone. RESULTS: Micro-CT analysis suggested that the femoral trabecular bone was porous with rod-like trabeculae with a scattered distribution in bone marrow, whereas alveolar bone showed a compact structure with plate-like trabeculae and limited bone marrow. Tissue mineral density, bone mineral density, bone volume fraction, and trabecular thickness were dramatically higher in the alveolar bone compared with that in the trabecular bone. Alveolar bone displayed lower trabecular number and trabecular separation. Histomorphometric analysis showed that alveolar bone was formed of compact bone with wide trabeculae, whereas femurs were composed of loose bone with finer trabeculae. CONCLUSIONS: In comparison to the spongiosa of the distal femur, alveolar bone displays specific morphological features with compact, wide, and highly mineralized trabeculae.


Asunto(s)
Maxilar , Animales , Femenino , Fémur/química , Fémur/diagnóstico por imagen , Fémur/fisiología , Maxilar/química , Maxilar/diagnóstico por imagen , Maxilar/fisiología , Ratas , Ratas Sprague-Dawley , Microtomografía por Rayos X
16.
J Cell Mol Med ; 21(12): 3231-3243, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28643466

RESUMEN

The osteoarthritis (OA) progression is now considered to be related to inflammation. Anemonin (ANE) is a small natural molecule extracted from various kinds of Chinese traditional herbs and has been shown to inhibiting inflammation response. In this study, we examined whether ANE could attenuate the progression of OA via suppression of IL-1ß/NF-κB pathway activation. Destabilization of the medial meniscus (DMM) was performed in 10-week-old male C57BL/6J mice. ANE was then intra-articularly injected into joint capsule for 8 and 12 weeks. Human articular chondrocytes and cartilage explants challenged with interleukin-1ß (IL-1ß) were treated with ANE. We found that ANE delayed articular cartilage degeneration in vitro and in vivo. In particular, proteoglycan loss and chondrocyte hypertrophy were significantly decreased in ANE -treated mice compared with vehicle-treated mice. ANE decreased the expressions of matrix metalloproteinase-13 (MMP13), A disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5), collagen X (Col X) while increasing Aggrecan level in murine with DMM surgery. ANE treatment also attenuated proteoglycan loss in human cartilage explants treated with IL-1ß ex vivo. ANE is a potent protective molecule for OA; it delays OA progression by suppressing ECM loss and chondrocyte hypertrophy partially by suppressing IL-1ß/NF-κB pathway activation.


Asunto(s)
Antiinflamatorios/farmacología , Cartílago Articular/efectos de los fármacos , Furanos/farmacología , Interleucina-1beta/genética , FN-kappa B/genética , Osteoartritis/tratamiento farmacológico , Proteína ADAMTS5/antagonistas & inhibidores , Proteína ADAMTS5/genética , Proteína ADAMTS5/metabolismo , Agrecanos/agonistas , Agrecanos/genética , Agrecanos/metabolismo , Animales , Cartílago Articular/metabolismo , Cartílago Articular/patología , Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Condrocitos/patología , Colágeno Tipo X/genética , Colágeno Tipo X/metabolismo , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Humanos , Inyecciones Intraarticulares , Interleucina-1beta/antagonistas & inhibidores , Interleucina-1beta/metabolismo , Cápsula Articular/efectos de los fármacos , Cápsula Articular/metabolismo , Cápsula Articular/patología , Masculino , Metaloproteinasa 13 de la Matriz/genética , Metaloproteinasa 13 de la Matriz/metabolismo , Ratones , Ratones Endogámicos C57BL , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , Osteoartritis/genética , Osteoartritis/metabolismo , Osteoartritis/patología , Cultivo Primario de Células , Transducción de Señal , Técnicas de Cultivo de Tejidos
17.
J Biol Chem ; 291(48): 24912-24921, 2016 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-27729453

RESUMEN

Chondrogenesis can regulate bone formation. Fibroblast growth factor receptor 3, highly expressed in chondrocytes, is a negative regulator of bone growth. To investigate whether chondrocyte FGFR3 regulates osteogenesis, thereby contributing to postnatal bone formation and bone remodeling, mice with conditional knock-out of Fgfr3 in chondrocytes (mutant (MUT)) were generated. MUT mice displayed overgrowth of bone with lengthened growth plates. Bone mass of MUT mice was significantly increased at both 1 month and 4 months of age. Histological analysis showed that osteoblast number and bone formation were remarkably enhanced after deletion of Fgfr3 in chondrocytes. Chondrocyte-osteoblast co-culture assay further revealed that Fgfr3 deficiency in chondrocytes promoted differentiation and mineralization of osteoblasts by up-regulating the expressions of Ihh, Bmp2, Bmp4, Bmp7, Wnt4, and Tgf-ß1, as well as down-regulating Nog expression. In addition, osteoclastogenesis was also impaired in MUT mice with decreased number of osteoclasts lining trabecular bone, which may be related to the reduced ratio of Rankl to Opg in Fgfr3-deficient chondrocytes. This study reveals that chondrocyte FGFR3 is involved in the regulation of bone formation and bone remodeling by a paracrine mechanism.


Asunto(s)
Condrocitos/metabolismo , Placa de Crecimiento/metabolismo , Osteogénesis/fisiología , Osteoprotegerina/biosíntesis , Comunicación Paracrina/fisiología , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/biosíntesis , Animales , Proteínas Morfogenéticas Óseas/biosíntesis , Proteínas Morfogenéticas Óseas/genética , Remodelación Ósea/fisiología , Células Cultivadas , Condrocitos/citología , Técnicas de Cocultivo , Placa de Crecimiento/citología , Ratones , Ratones Noqueados , Tamaño de los Órganos/fisiología , Osteoblastos/citología , Osteoblastos/metabolismo , Osteoclastos/citología , Osteoclastos/metabolismo , Osteoprotegerina/genética , Ligando RANK/biosíntesis , Ligando RANK/genética , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/genética , Factor de Crecimiento Transformador beta1/genética , Proteína Wnt4/biosíntesis , Proteína Wnt4/genética
18.
Neuroepidemiology ; 44(1): 39-44, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25720916

RESUMEN

BACKGROUND: The field of quantifying the association between the intake of vitamin C and risk of glioma still has conflicts. Thus, we performed a comprehensive meta-analysis to test the hypothesis that a high intake of vitamin C may be a protective effect on glioma risk. METHODS: Pertinent studies were identified by a search in PubMed and Web of Knowledge up to June 2014. The random-effect model was used to combine study-specific results. Publication bias was estimated using Begg' funnel plot and Egger's regression asymmetry test. RESULTS: Thirteen articles with 15 studies (2 cohort study and 13 case-control studies) involving 3,409 glioma cases about vitamin C intake and glioma risk were used in this meta-analysis. The combined relative risks (RRs) of glioma associated with vitamin C intake was 0.86 (95% CIs = 0.75-0.99). Overall, significant protective associations were also found in the American population (RRs = 0.85, 95% CIs = 0.73-0.98) and case-control studies (RRs = 0.80, 95% CIs = 0.69-0.93). No publication bias was found. CONCLUSIONS: Our analysis indicated that vitamin C intake might decrease the risk of glioma, especially among the Americans.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Neoplasias Encefálicas/epidemiología , Dieta , Glioma/epidemiología , Neoplasias Encefálicas/prevención & control , Glioma/prevención & control , Humanos , Riesgo
20.
Theranostics ; 14(1): 265-282, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38164153

RESUMEN

Lymphatic vessel networks are a main part of the vertebrate cardiovascular system, which participate in various physiological and pathological processes via regulation of fluid transport and immunosurveillance. Targeting lymphatic vessels has become a potent strategy for treating various human diseases. The presence of varying degrees of inflammation in joints of rheumatoid arthritis (RA) and osteoarthritis (OA), characterized by heightened infiltration of inflammatory cells, increased levels of inflammatory factors, and activation of inflammatory signaling pathways, significantly contributes to the disruption of cartilage and bone homeostasis in arthritic conditions. Increasing evidence has demonstrated the pivotal role of lymphatic vessels in maintaining joint homeostasis, with their pathological alterations closely associated with the initiation and progression of inflammatory joint diseases. In this review, we provide a comprehensive overview of the evolving knowledge regarding the structural and functional aspects of lymphatic vessels in the pathogenesis of RA and OA. In addition, we summarized the potential regulatory mechanisms underlying the modulation of lymphatic function in maintaining joint homeostasis during inflammatory conditions, and further discuss the distinctions between RA and OA. Moreover, we describe therapeutic strategies for inflammatory arthritis based on lymphatic vessels, including the promotion of lymphangiogenesis, restoration of proper lymphatic vessel function through anti-inflammatory approaches, enhancement of lymphatic contractility and drainage, and alleviation of congestion within the lymphatic system through the elimination of inflammatory cells. At last, we envisage potential research perspectives and strategies to target lymphatic vessels in treating these inflammatory joint diseases.


Asunto(s)
Artritis Reumatoide , Vasos Linfáticos , Osteoartritis , Humanos , Artritis Reumatoide/patología , Osteoartritis/metabolismo , Vasos Linfáticos/metabolismo , Inflamación/metabolismo , Linfangiogénesis
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