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1.
Cell ; 153(5): 1012-24, 2013 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-23706739

RESUMO

Histone acetylation plays critical roles in chromatin remodeling, DNA repair, and epigenetic regulation of gene expression, but the underlying mechanisms are unclear. Proteasomes usually catalyze ATP- and polyubiquitin-dependent proteolysis. Here, we show that the proteasomes containing the activator PA200 catalyze the polyubiquitin-independent degradation of histones. Most proteasomes in mammalian testes ("spermatoproteasomes") contain a spermatid/sperm-specific α subunit α4 s/PSMA8 and/or the catalytic ß subunits of immunoproteasomes in addition to PA200. Deletion of PA200 in mice abolishes acetylation-dependent degradation of somatic core histones during DNA double-strand breaks and delays core histone disappearance in elongated spermatids. Purified PA200 greatly promotes ATP-independent proteasomal degradation of the acetylated core histones, but not polyubiquitinated proteins. Furthermore, acetylation on histones is required for their binding to the bromodomain-like regions in PA200 and its yeast ortholog, Blm10. Thus, PA200/Blm10 specifically targets the core histones for acetylation-mediated degradation by proteasomes, providing mechanisms by which acetylation regulates histone degradation, DNA repair, and spermatogenesis.


Assuntos
Reparo do DNA , Histonas/metabolismo , Proteínas Nucleares/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Espermatogênese , Testículo/metabolismo , Acetilação , Sequência de Aminoácidos , Animais , Quebras de DNA de Cadeia Dupla , Humanos , Masculino , Camundongos , Dados de Sequência Molecular , Proteínas Nucleares/química , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência
2.
Nat Immunol ; 16(3): 237-45, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25642820

RESUMO

Mycobacterium tuberculosis PtpA, a secreted tyrosine phosphatase essential for tuberculosis pathogenicity, could be an ideal target for a drug against tuberculosis, but its active-site inhibitors lack selectivity over human phosphatases. Here we found that PtpA suppressed innate immunity dependent on pathways of the kinases Jnk and p38 and the transcription factor NF-κB by exploiting host ubiquitin. Binding of PtpA to ubiquitin via a region with no homology to human proteins activated it to dephosphorylate phosphorylated Jnk and p38, leading to suppression of innate immunity. Furthermore, the host adaptor TAB3 mediated NF-κB signaling by sensing ubiquitin chains, and PtpA blocked this process by competitively binding the ubiquitin-interacting domain of TAB3. Our findings reveal how pathogens subvert innate immunity by coopting host ubiquitin and suggest a potential tuberculosis treatment via targeting of ubiquitin-PtpA interfaces.


Assuntos
Imunidade Inata/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Ubiquitina/imunologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Células HEK293 , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Masculino , Camundongos Endogâmicos C57BL , NF-kappa B/imunologia , Fosforilação , Transdução de Sinais/imunologia , Tuberculose/microbiologia , Células U937
3.
Circ Res ; 134(3): 252-265, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166470

RESUMO

BACKGROUND: Intracellular Ca2+ cycling determines myocardial contraction and relaxation in response to physiological demands. SERCA2a (sarcoplasmic/endoplasmic reticulum Ca2+-ATPase 2a) is responsible for the sequestration of cytosolic Ca2+ into intracellular stores during cardiac relaxation, and its activity is reversibly inhibited by PLN (phospholamban). However, the regulatory hierarchy of SERCA2a activity remains unclear. METHODS: Cardiomyocyte-specific ZBTB20 knockout mice were generated by crossing ZBTB20flox mice with Myh6-Cre mice. Echocardiography, blood pressure measurements, Langendorff perfusion, histological analysis and immunohistochemistry, quantitative reverse transcription-PCR, Western blot analysis, electrophysiological measurements, and chromatin immunoprecipitation assay were performed to clarify the phenotype and elucidate the molecular mechanisms. RESULTS: Specific ablation of ZBTB20 in cardiomyocyte led to a significant increase in basal myocardial contractile parameters both in vivo and in vitro, accompanied by an impairment in cardiac reserve and exercise capacity. Moreover, the cardiomyocytes lacking ZBTB20 showed an increase in sarcoplasmic reticular Ca2+ content and exhibited a remarkable enhancement in both SERCA2a activity and electrically stimulated contraction. Mechanistically, PLN expression was dramatically reduced in cardiomyocytes at the mRNA and protein levels by ZBTB20 deletion or silencing, and PLN overexpression could largely restore the basal contractility in ZBTB20-deficient cardiomyocytes. CONCLUSIONS: These data point to ZBTB20 as a fine-tuning modulator of PLN expression and SERCA2a activity, thereby offering new perspective on the regulation of basal contractility in the mammalian heart.


Assuntos
Miocárdio , Retículo Sarcoplasmático , Animais , Camundongos , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Mamíferos , Camundongos Knockout , Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo
4.
Nature ; 581(7808): 278-282, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32433619

RESUMO

Human eyes possess exceptional image-sensing characteristics such as an extremely wide field of view, high resolution and sensitivity with low aberration1. Biomimetic eyes with such characteristics are highly desirable, especially in robotics and visual prostheses. However, the spherical shape and the retina of the biological eye pose an enormous fabrication challenge for biomimetic devices2,3. Here we present an electrochemical eye with a hemispherical retina made of a high-density array of nanowires mimicking the photoreceptors on a human retina. The device design has a high degree of structural similarity to a human eye with the potential to achieve high imaging resolution when individual nanowires are electrically addressed. Additionally, we demonstrate the image-sensing function of our biomimetic device by reconstructing the optical patterns projected onto the device. This work may lead to biomimetic photosensing devices that could find use in a wide spectrum of technological applications.


Assuntos
Materiais Biomiméticos , Biomimética/instrumentação , Compostos de Cálcio , Nanofios , Óxidos , Retina , Titânio , Desenho de Equipamento , Humanos , Robótica/instrumentação , Visão Ocular
5.
Int Urogynecol J ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695902

RESUMO

INTRODUCTION AND HYPOTHESIS: The potential predictors of pelvic floor reconstruction surgery hypothermia remain unclear. This prospective cohort study was aimed at identifying these predictors and evaluating the outcomes associated with perioperative hypothermia. METHODS: Elderly patients undergoing pelvic floor reconstruction surgery were consecutively enrolled from April 2023 to September 2023. Perioperative temperature was measured at preoperative (T1), every 15 min after the start of anesthesia (T2), and 15 min postoperative (T3) using a temperature probe. Perioperative hypothermia was defined as a core temperature below 36°C at any point during the procedure. Multivariate logistic regression analysis was conducted to determine factors associated with perioperative hypothermia. RESULTS: A total of 229 patients were included in the study, with 50.7% experiencing hypothermia. Multivariate analysis revealed that the surgical method involving pelvic floor combined with laparoscopy, preoperative temperature < 36.5°C, anesthesia duration ≥ 120 min, and the high levels of anxiety were significantly associated with perioperative hypothermia. The predictive value of the multivariate model was 0.767 (95% CI, 0.706 to 0.828). CONCLUSIONS: This observational prospective study identified several predictive factors for perioperative hypothermia in elderly patients during pelvic floor reconstruction surgery. Strategies aimed at preventing perioperative hypothermia should target these factors. Further studies are required to assess the effectiveness of these strategies, specifically in elderly patients undergoing pelvic floor reconstruction surgery.

6.
BMC Nephrol ; 25(1): 46, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302918

RESUMO

BACKGROUND AND OBJECTIVES: The psychological problems of hemodialysis (HD) patients are prominent, and benefit finding (BF) have been proven beneficial to physical and mental health, fewer researchers explored BF in HD patients. The aim of this study was to investigate the current status of BF in patients with chronic kidney disease and to analyze the factors influencing it in order to provide a reference for subsequent interventions. METHODS: A cross-sectional study was done on 246 HD patients by convenience sampling in the hemodialysis center of a 3 A hospital in Shanghai from March to September 2019. The measures include General Information Questionnaire, Benefit Finding Scale, Perceived Social Support Scale, General Self-efficacy Scale, and Simplified Coping Style scale. RESULTS: The median (interquartile range, IQR) score of BF was 66 (IQR = 19) and it was lower compared with other chronic diseases. Significant differences in BF scores were found between different age groups, HD duration categories, and understanding degrees of HD. Taking BF as the dependent variable, the results of multiple linear regression analysis showed that age, duration of HD, family support, other support, positive coping, and self-efficacy entered the regression equation to explain 43.8% of the total variation. Social support played an indirect effect in the relationship between positive coping and BF, accounting for 54.1% of the total effect. CONCLUSION: The BF of HD patients is worrisome and affected by many factors. Medical staff could pay attention to the positive psychology of HD patients, and construct individualized interventions according to the influencing factors to improve their BF level and achieve physical and mental health.


Assuntos
Adaptação Psicológica , Insuficiência Renal Crônica , Humanos , Estudos Transversais , China/epidemiologia , Diálise Renal/psicologia , Insuficiência Renal Crônica/terapia
7.
BMC Anesthesiol ; 24(1): 212, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918712

RESUMO

BACKGROUND: 3% chloroprocaine (CP) has been reported as the common local anesthetic used in pregnant women undergoing urgent cesarean delivery during labor analgesia period. However, 0.75% ropivacaine is considered a promising and effective alternative. Therefore, we conducted a randomized controlled trial to compare the effectiveness and safety of 0.75% ropivacaine with 3% chloroprocaine for extended epidural anesthesia in pregnant women. METHODS: We conducted a double-blind, randomized, controlled, single-center study from November 1, 2022, to April 30, 2023. We selected forty-five pregnant women undergoing urgent cesarean delivery during labor analgesia period and randomized them to receive either 0.75% ropivacaine or 3% chloroprocaine in a 1:1 ratio. The primary outcome was the time to loss of cold sensation at the T4 level. RESULTS: There was a significant difference between the two groups in the time to achieve loss of cold sensation (303, 95%CI 255 to 402 S vs. 372, 95%CI 297 to 630 S, p = 0.024). There was no significant difference the degree of motor block (p = 0.185) at the Th4 level. Fewer pregnant women required additional local anesthetics in the ropivacaine group compared to the chloroprocaine group (4.5% VS. 34.8%, p = 0.011). The ropivacaine group had lower intraoperative VAS scores (p = 0.023) and higher patient satisfaction scores (p = 0.040) than the chloroprocaine group. The incidence of intraoperative complications was similar between the two groups, and no serious complications were observed. CONCLUSIONS: Our study found that 0.75% ropivacaine was associated with less intraoperative pain treatment, higher patient satisfaction and reduced the onset time compared to 3% chloroprocaine in pregnant women undergoing urgent cesarean delivery during labor analgesia period. Therefore, 0.75% ropivacaine may be a suitable drug in pregnant women undergoing urgent cesarean delivery during labor analgesia period. CLINICAL TRIAL NUMBER AND REGISTRY URL: The registration number: ChiCTR2200065201; http://www.chictr.org.cn , Principal investigator: MEN, Date of registration: 31/10/2022.


Assuntos
Analgesia Obstétrica , Anestésicos Locais , Cesárea , Procaína , Ropivacaina , Humanos , Feminino , Ropivacaina/administração & dosagem , Gravidez , Método Duplo-Cego , Cesárea/métodos , Anestésicos Locais/administração & dosagem , Adulto , Analgesia Obstétrica/métodos , Procaína/análogos & derivados , Procaína/administração & dosagem
8.
Int J Mol Sci ; 25(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38891826

RESUMO

Cellular senescence is closely related to DNA damage, proteasome inactivity, histone loss, epigenetic alterations, and tumorigenesis. The mammalian proteasome activator PA200 (also referred to as PSME4) or its yeast ortholog Blm10 promotes the acetylation-dependent degradation of the core histones during transcription, DNA repair, and spermatogenesis. According to recent studies, PA200 plays an important role in senescence, probably because of its role in promoting the degradation of the core histones. Loss of PA200 or Blm10 is a major cause of the decrease in proteasome activity during senescence. In this paper, recent research progress on the association of PA200 with cellular senescence is summarized, and the potential of PA200 to serve as a therapeutic target in age-related diseases is discussed.


Assuntos
Senescência Celular , Complexo de Endopeptidases do Proteassoma , Proteólise , Complexo de Endopeptidases do Proteassoma/metabolismo , Humanos , Animais , Histonas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas Nucleares
9.
Neurobiol Dis ; 183: 106164, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37217103

RESUMO

Phototherapy is an emerging non-pharmacological treatment for depression, circadian rhythm disruptions, and neurodegeneration, as well as pain conditions including migraine and fibromyalgia. However, the mechanism of phototherapy-induced antinociception is not well understood. Here, using fiber photometry recordings of population-level neural activity combined with chemogenetics, we found that phototherapy elicits antinociception via regulation of the ventral lateral geniculate body (vLGN) located in the visual system. Specifically, both green and red lights caused an increase of c-fos in vLGN, with red light increased more. In vLGN, green light causes a large increase in glutamatergic neurons, whereas red light causes a large increase in GABAergic neurons. Green light preconditioning increases the sensitivity of glutamatergic neurons to noxious stimuli in vLGN of PSL mice. Green light produces antinociception by activating glutamatergic neurons in vLGN, and red light promotes nociception by activating GABAergic neurons in vLGN. Together, these results demonstrate that different colors of light exert different pain modulation effects by regulating glutamatergic and GABAergic subpopulations in the vLGN. This may provide potential new therapeutic strategies and new therapeutic targets for the precise clinical treatment of neuropathic pain.


Assuntos
Neuralgia , Nociceptividade , Camundongos , Animais , Nociceptividade/fisiologia , Neurônios GABAérgicos , Corpos Geniculados/fisiologia , Fototerapia , Neuralgia/terapia
10.
BMC Plant Biol ; 23(1): 474, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37807079

RESUMO

BACKGROUND: Clonal plants can successfully adapt to various ecosystems. A trade-off between sexual and clonal reproduction is generally assumed in clonal plants, which may be influenced both by the characteristics of the plant itself and environmental conditions. Currently, it is unclear how climate change, and specifically warming and increased precipitation, might affect sexual and clonal reproduction in clonal plants. Therefore, this study aimed to investigate both the sexual and clonal reproduction responses of Stipa breviflora to warming and increased precipitation. A controlled experiment was conducted by inducing increases in precipitation (ambient condition, 25% and 50% increases) and warming (ambient temperature, 1.5 °C and 3.0 °C increases). RESULTS: Warming significantly influenced both the ratio of reproductive ramet shoot biomass to total shoot biomass, and the ratio of reproductive ramet number to total ramet number. Additionally, the ratio of reproductive ramet shoot biomass to total shoot biomass was also significantly affected by increased precipitation. Increased precipitation benefited sexual reproduction, while effects of warming on reproductive and/or vegetative ramets varied from negative to positive depending on precipitation conditions. There was no relationship between the number or shoot biomass of reproductive ramets and vegetative ramets. Reproductive ramets displayed greater sensitivity to climate change than vegetative ramets. CONCLUSIONS: The findings of our study suggest that there was no trade-off between sexual and clonal reproduction in S. breviflora. The combined impact of warming and increased precipitation promoted sexual reproduction but did not inhibit clonal reproduction. Clonal plants with the capacity for both sexual and clonal reproduction, may cope with climate change well via clonal reproduction, ensuring their survival.


Assuntos
Ecossistema , Reprodução , Poaceae/fisiologia , Biomassa , Células Clonais
11.
Gastrointest Endosc ; 98(4): 642-652, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37356634

RESUMO

BACKGROUND AND AIMS: EUS is essential in diagnosing and staging of esophageal subepithelial lesions and tumors. However, EUS is invasive, relies on highly trained endoscopists, and typically requires sedation. The newly developed US capsule endoscopy (USCE), which incorporates both white-light and US imaging modalities into a tethered capsule, is a minimally invasive method for obtaining superficial and submucosal information of the esophagus. This study aimed to assess the feasibility and safety of this USCE system. METHODS: Twenty participants were enrolled: 10 healthy volunteers and 10 patients with esophageal lesions indicated for EUS. Participants first underwent USCE and subsequently EUS within 48 hours. The primary outcome was the technical success rate of USCE. Secondary outcomes were safety, visualization of the esophagus, and comfort assessment. RESULTS: The technical success rate of USCE was 95% because 1 patient failed to swallow the capsule. No adverse events were observed. The esophagus was well visualized, and all lesions were detected under USCE optical mode in 19 participants. For healthy volunteers, the US images of normal esophageal walls were all characterized by differentiated 7-layer architecture under both USCE and EUS. For 9 patients, the features of esophageal lesions were recognized clearly under USCE, and presumptive diagnoses derived from USCE were all consistent with those from EUS. Most participants preferred USCE to EUS. CONCLUSIONS: The novel USCE is feasible and safe to observe the esophageal mucosa and acquire submucosal information, which has the potential to be widely used in the clinic. (Clinical trial registration number: NCT05054933.).


Assuntos
Endoscopia por Cápsula , Neoplasias Esofágicas , Humanos , Neoplasias Esofágicas/patologia , Endossonografia/métodos , Diagnóstico por Imagem
12.
Endoscopy ; 55(1): 52-57, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35820437

RESUMO

BACKGROUND : Certain patients experience difficulty swallowing a video capsule endoscopy (VCE) device owing to its relatively large size. The newly developed small-sized magnetically controlled capsule endoscopy (MCE) device is the smallest VCE device ever reported. We aimed to evaluate the performance of the small-sized MCE device in terms of ingestion and examination efficacy. METHODS : Patients in two centers were prospectively enrolled and randomized to the small-sized or standard MCE groups. Differences in capsule ingestion difficulties, visualization of the gastrointestinal tract, and capsule transit times were compared. RESULTS : 96 patients were enrolled (48 in each group). In the small-sized MCE group, the mean (SD) difficulty score and time to swallow the capsule, and success rate for swallowing the capsule at the first attempt were 0.6 (1.0), 3.4 (1.3) seconds, and 89.6 %, which was significant better compared with the standard MCE group with 3.1 (1.7), 12.0 (14.3) seconds and 60.4 %, respectively (all P < 0.001). Visualization of the esophagus, stomach, and small bowel were comparable between the two groups. The small-sized MCE group had a significantly shorter gastric transit time (49.4 minutes vs. 66.2 minutes; P = 0.04) and longer small-bowel transit time (5.8 hours vs. 5.0 hours; P = 0.045). CONCLUSIONS : The small-sized MCE device is feasible and safe for gastrointestinal examination, alleviating difficulties in capsule ingestion, improving gastric emptying under magnetic control, and prolonging the small-bowel transit time.


Assuntos
Endoscopia por Cápsula , Humanos , Adulto , Endoscopia por Cápsula/métodos , Estômago , Intestino Delgado/diagnóstico por imagem , Esôfago , Fenômenos Magnéticos , Trânsito Gastrointestinal
13.
EMBO Rep ; 22(6): e52175, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-33938130

RESUMO

Upon Mycobacterium tuberculosis (Mtb) infection, protein kinase G (PknG), a eukaryotic-type serine-threonine protein kinase (STPK), is secreted into host macrophages to promote intracellular survival of the pathogen. However, the mechanisms underlying this PknG-host interaction remain unclear. Here, we demonstrate that PknG serves both as a ubiquitin-activating enzyme (E1) and a ubiquitin ligase (E3) to trigger the ubiquitination and degradation of tumor necrosis factor receptor-associated factor 2 (TRAF2) and TGF-ß-activated kinase 1 (TAK1), thereby inhibiting the activation of NF-κB signaling and host innate responses. PknG promotes the attachment of ubiquitin (Ub) to the ubiquitin-conjugating enzyme (E2) UbcH7 via an isopeptide bond (UbcH7 K82-Ub), rather than the usual C86-Ub thiol-ester bond. PknG induces the discharge of Ub from UbcH7 by acting as an isopeptidase, before attaching Ub to its substrates. These results demonstrate that PknG acts as an unusual ubiquitinating enzyme to remove key components of the innate immunity system, thus providing a potential target for tuberculosis treatment.


Assuntos
Mycobacterium tuberculosis , Proteínas Quinases Dependentes de GMP Cíclico , Mycobacterium tuberculosis/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Ubiquitina/genética , Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
14.
BMC Gastroenterol ; 23(1): 76, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36927462

RESUMO

BACKGROUNDS AND AIMS: Complete and consecutive observation of the gastrointestinal (GI) tract continues to present challenges for current endoscopy systems. We developed a novel upper and mid gastrointestinal (UMGI) capsule endoscopy using the modified detachable string magnetically controlled capsule endoscopy (DS-MCE) and inspection method and aimed to assess the clinical application. METHODS: Patients were recruited to undergo UMGI capsule endoscopy followed by esophagogastroduodenoscopy. All capsule procedures in the upper gastrointestinal (UGI) tract were conducted under the control of magnet and string. The main outcome was technical success, and the secondary outcomes included visualization of the UMGI tract, examination time, diagnostic yield, compliance, and safety evaluation. RESULTS: Thirty patients were enrolled and all UMGI capsule procedures realized repeated observation of the esophagus and duodenum with detection rates of 100.0%, 80.0%, and 86.7% of Z-line, duodenal papilla, and reverse side of pylorus, respectively. String detachment was succeeded in 29 patients (96.7%) and the complete examination rate of UMGI tract was 95.45% (21/22). All UMGI capsule procedures were well tolerated with low discomfort score, and had a good diagnostic yield with per-lesion sensitivity of 96.2% in UGI diseases. No adverse events occurred. CONCLUSIONS: This new capsule endoscopy system provides an alternative screening modality for the UMGI tract, and might be indicated in cases of suspected upper and small bowel GI bleeding. Trial registration DS-MCE-UGI and SB, NCT04329468. Registered 27 March 2020, https://clinicaltrials.gov/ct2/results?cond=&term=NCT04329468 .


Assuntos
Endoscopia por Cápsula , Trato Gastrointestinal Superior , Humanos , Endoscopia por Cápsula/métodos , Esôfago , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiologia
15.
Acta Pharmacol Sin ; 44(2): 465-474, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35953645

RESUMO

Survival is one of the most important endpoints in cancer therapy, and parametric survival analysis could comprehensively reveal the overall result of disease progression, drug efficacy, toxicity as well as their interactions. In this study we investigated the efficacy and toxicity of dexamethasone (DEX) combined with gemcitabine (GEM) in pancreatic cancer xenograft. Nude mice bearing SW1990 pancreatic cancer cells derived tumor were treated with DEX (4 mg/kg, i.g.) and GEM (15 mg/kg, i.v.) alone or in combination repeatedly (QD, Q3D, Q7D) until the death of animal or the end of study. Tumor volumes and net body weight (NBW) were assessed every other day. Taking NBW as a systemic safety indicator, an integrated pharmacokinetic/pharmacodynamic (PK/PD) model was developed to quantitatively describe the impact of tumor size and systemic safety on animal survival. The PK/PD models with time course data for tumor size and NBW were established, respectively, in a sequential manner; a parametric time-to-event (TTE) model was also developed based on the longitudinal PK/PD models to describe the survival results of the SW1990 tumor-bearing mice. These models were evaluated and externally validated. Only the mice with good tumor growth inhibition and relatively stable NBW had an improved survival result after DEX and GEM combination therapy, and the simulations based on the parametric TTE model showed that NBW played more important role in animals' survival compared with tumor size. The established model in this study demonstrates that tumor size was not always the most important reason for cancer-related death, and parametric survival analysis together with safety issues was also important in the evaluation of oncology therapies in preclinical studies.


Assuntos
Gencitabina , Neoplasias Pancreáticas , Humanos , Camundongos , Animais , Linhagem Celular Tumoral , Xenoenxertos , Camundongos Nus , Neoplasias Pancreáticas/tratamento farmacológico
16.
Acta Pharmacol Sin ; 44(8): 1600-1611, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36973542

RESUMO

Epilepsy is one common brain disorder, which is not well controlled by current pharmacotherapy. In this study we characterized the therapeutic potential of borneol, a plant-derived bicyclic monoterpene compound, in the treatment of epilepsy and elucidated the underlying mechanisms. The anti-seizure potency and properties of borneol were assessed in both acute and chronic mouse epilepsy models. Administration of (+)-borneol (10, 30, 100 mg/kg, i.p.) dose-dependently attenuated acute epileptic seizure in maximal-electroshock seizure (MES) and pentylenetetrazol (PTZ)-induced seizure models without obvious side-effect on motor function. Meanwhile, (+)-borneol administration retarded kindling-induced epileptogenesis and relieved fully kindled seizures. Importantly, (+)-borneol administration also showed therapeutic potential in kainic acid-induced chronic spontaneous seizure model, which was considered as a drug-resistant model. We compared the anti-seizure efficacy of 3 borneol enantiomers in the acute seizure models, and found (+)-borneol being the most satisfying one with long-term anti-seizure effect. In electrophysiological study conducted in mouse brain slices containing the subiculum region, we revealed that borneol enantiomers displayed different anti-seizure mechanisms, (+)-borneol (10 µM) markedly suppressed the high frequency burst firing of subicular neurons and decreased glutamatergic synaptic transmission. In vivo calcium fiber photometry analysis further verified that administration of (+)-borneol (100 mg/kg) inhibited the enhanced glutamatergic synaptic transmission in epilepsy mice. We conclude that (+)-borneol displays broad-spectrum anti-seizure potential in different experimental models via decreasing the glutamatergic synaptic transmission without obvious side-effect, suggesting (+)-borneol as a promising anti-seizure compound for pharmacotherapy in epilepsy.


Assuntos
Epilepsia , Excitação Neurológica , Camundongos , Animais , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Epilepsia/induzido quimicamente , Epilepsia/tratamento farmacológico , Canfanos/uso terapêutico , Canfanos/farmacologia , Excitação Neurológica/fisiologia , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Modelos Animais de Doenças
17.
Acta Pharmacol Sin ; 44(12): 2376-2387, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37488426

RESUMO

Cognitive deficit is a common comorbidity in temporal lobe epilepsy (TLE) and is not well controlled by current therapeutics. How epileptic seizure affects cognitive performance remains largely unclear. In this study we investigated the role of subicular seizure-activated neurons in cognitive impairment in TLE. A bipolar electrode was implanted into hippocampal CA3 in male mice for kindling stimulation and EEG recording; a special promoter with enhanced synaptic activity-responsive element (E-SARE) was used to label seizure-activated neurons in the subiculum; the activity of subicular seizure-activated neurons was manipulated using chemogenetic approach; cognitive function was assessed in object location memory (OLM) and novel object recognition (NOR) tasks. We showed that chemogenetic inhibition of subicular seizure-activated neurons (mainly CaMKIIα+ glutamatergic neurons) alleviated seizure generalization and improved cognitive performance, but inhibition of seizure-activated GABAergic interneurons had no effect on seizure and cognition. For comparison, inhibition of the whole subicular CaMKIIα+ neuron impaired cognitive function in naïve mice in basal condition. Notably, chemogenetic inhibition of subicular seizure-activated neurons enhanced the recruitment of cognition-responsive c-fos+ neurons via increasing neural excitability during cognition tasks. Our results demonstrate that subicular seizure-activated neurons contribute to cognitive impairment in TLE, suggesting seizure-activated neurons as the potential therapeutic target to alleviate cognitive impairment in TLE.


Assuntos
Disfunção Cognitiva , Epilepsia do Lobo Temporal , Masculino , Camundongos , Animais , Convulsões , Neurônios , Epilepsia do Lobo Temporal/psicologia , Hipocampo , Cognição
18.
Acta Pharmacol Sin ; 44(9): 1737-1747, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37076634

RESUMO

Epilepsy is not well controlled by current anti-seizure drugs (ASDs). High mobility group box 1 (HMGB1) is a DNA-binding protein in the nucleus regulating transcriptional activity and maintaining chromatin structure and DNA repair. In epileptic brains, HMGB1 is released by activated glia and neurons, interacting with various receptors like Toll-like receptor 4 (TLR4) and downstream glutamatergic NMDA receptor, thus enhancing neural excitability. But there is a lack of small-molecule drugs targeting the HMGB1-related pathways. In this study we evaluated the therapeutic potential of inflachromene (ICM), an HMGB-targeting small-molecule inhibitor, in mouse epilepsy models. Pentylenetetrazol-, kainic acid- and kindling-induced epilepsy models were established in mice. The mice were pre-treated with ICM (3, 10 mg/kg, i.p.). We showed that ICM pretreatment significantly reduced the severity of epileptic seizures in all the three epilepsy models. ICM (10 mg/kg) exerted the most apparent anti-seizure effect in kainic acid-induced epileptic status (SE) model. By immunohistochemical analysis of brain sections from kainic acid-induced SE mice, we found that kainic acid greatly enhanced HMGB1 translocation in the hippocampus, which was attenuated by ICM pretreatment in subregion- and cell type-dependent manners. Notably, in CA1 region, the seizure focus, ICM pretreatment mainly inhibited HMGB1 translocation in microglia. Furthermore, the anti-seizure effect of ICM was related to HMGB1 targeting, as pre-injection of anti-HMGB1 monoclonal antibody (5 mg/kg, i.p.) blocked the seizure-suppressing effect of ICM in kainic acid-induced SE model. In addition, ICM pretreatment significantly alleviated pyramidal neuronal loss and granule cell dispersion in kainic acid-induced SE model. These results demonstrate that ICM is an HMGB-targeting small molecule with anti-seizure potential, which may help develop a potential drug for treating epilepsy.


Assuntos
Epilepsia , Proteína HMGB1 , Camundongos , Animais , Ácido Caínico/efeitos adversos , Ácido Caínico/metabolismo , Epilepsia/induzido quimicamente , Epilepsia/tratamento farmacológico , Epilepsia/metabolismo , Hipocampo/metabolismo , Proteínas HMGB/metabolismo , Proteínas HMGB/farmacologia , Proteína HMGB1/metabolismo , Modelos Animais de Doenças
19.
World J Surg ; 47(6): 1444-1456, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36826487

RESUMO

BACKGROUND: Surgery is the preferred treatment option for the elderly patients with hip fractures. However, the choice of general anesthesia (GA) or regional anesthesia (RA) remains controversial. The quality of evidence has further improved with the advent of several high-quality randomized clinical trials (RCTs) in the last two years. The purpose of this study was to compare the clinical outcomes of two anesthetic techniques in elderly patients undergoing hip fracture surgeries. METHODS: Eligible studies were identified from PubMed/MEDLINE, Web of Science, Scopus, EMBASE and reference lists from January 2000 to June 2022 in this current systematic review and meta-analysis. The outcomes included the surgery-related outcomes (duration of surgery, duration of anesthesia, intraoperative blood loss and number of transfusions) and postoperative outcomes (30-day mortality, postoperative delirium,cardiovascular events and other complications). RESULTS: A total of 10 RCTs were included, and a total of 3594 patients were analyzed. RA was associated with shorter duration of surgery, shorter length of hospital stays and less intraoperative blood loss compared to GA. There were no significant differences between the two groups in the number of blood transfusions, duration of anesthesia, 30-day mortality or postoperative delirium. CONCLUSIONS: Our pooled analysis identified no significant differences in terms of the safety between RA and GA, while RA reduces intraoperative blood loss, length of hospital stays and duration of surgery. These results suggest that RA appears to be preferable for the elderly patients with hip fractures.


Assuntos
Anestesia por Condução , Delírio do Despertar , Fraturas do Quadril , Humanos , Idoso , Perda Sanguínea Cirúrgica/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Anestesia Geral , Fraturas do Quadril/cirurgia
20.
Proc Natl Acad Sci U S A ; 117(11): 6067-6074, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32123064

RESUMO

Ocular inflammation is a major cause of visual impairment attributed to dysregulation of the immune system. Previously, we have shown that the receptor for growth-hormone-releasing hormone (GHRH-R) affects multiple inflammatory processes. To clarify the pathological roles of GHRH-R in acute ocular inflammation, we investigated the inflammatory cascades mediated by this receptor. In human ciliary epithelial cells, the NF-κB subunit p65 was phosphorylated in response to stimulation with lipopolysaccharide (LPS), resulting in transcriptional up-regulation of GHRH-R. Bioinformatics analysis and coimmunoprecipitation showed that GHRH-R had a direct interaction with JAK2. JAK2, but not JAK1, JAK3, and TYK2, was elevated in ciliary body and iris after treatment with LPS in a rat model of endotoxin-induced uveitis. This elevation augmented the phosphorylation of STAT3 and production of proinflammatory factors, including IL-6, IL-17A, COX2, and iNOS. In explants of iris and ciliary body, the GHRH-R antagonist, MIA-602, suppressed phosphorylation of STAT3 and attenuated expression of downstream proinflammatory factors after LPS treatment. A similar suppression of STAT3 phosphorylation was observed in human ciliary epithelial cells. In vivo studies showed that blocking of the GHRH-R/JAK2/STAT3 axis with the JAK inhibitor Ruxolitinib alleviated partially the LPS-induced acute ocular inflammation by reducing inflammatory cells and protein leakage in the aqueous humor and by repressing expression of STAT3 target genes in rat ciliary body and iris and in human ciliary epithelial cells. Our findings indicate a functional role of the GHRH-R/JAK2/STAT3-signaling axis in acute anterior uveitis and suggest a therapeutic strategy based on treatment with antagonists targeting this signaling pathway.


Assuntos
Células Epiteliais/patologia , Receptores de Neuropeptídeos/metabolismo , Receptores de Hormônios Reguladores de Hormônio Hipofisário/metabolismo , Transdução de Sinais/imunologia , Uveíte/patologia , Animais , Linhagem Celular , Corpo Ciliar/citologia , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/imunologia , Humanos , Janus Quinase 2/metabolismo , Lipopolissacarídeos/imunologia , Masculino , Nitrilas , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Pirimidinas , Ratos , Receptores de Neuropeptídeos/antagonistas & inibidores , Receptores de Neuropeptídeos/imunologia , Receptores de Hormônios Reguladores de Hormônio Hipofisário/antagonistas & inibidores , Receptores de Hormônios Reguladores de Hormônio Hipofisário/imunologia , Fator de Transcrição STAT3/metabolismo , Sermorelina/análogos & derivados , Sermorelina/farmacologia , Sermorelina/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Uveíte/tratamento farmacológico , Uveíte/imunologia
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