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1.
Development ; 151(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38063853

RESUMEN

High-sugar diets (HSDs) often lead to obesity and type 2 diabetes, both metabolic syndromes associated with stem cell dysfunction. However, it is unclear whether excess dietary sugar affects stem cells. Here, we report that HSD impairs stem cell function in the intestine and ovaries of female Drosophila prior to the onset of insulin resistance, a hallmark of type 2 diabetes. Although 1 week of HSD leads to obesity, impaired oogenesis and altered lipid metabolism, insulin resistance does not occur. HSD increases glucose uptake by germline stem cells (GSCs) and triggers reactive oxygen species-induced JNK signaling, which reduces GSC proliferation. Removal of excess sugar from the diet reverses these HSD-induced phenomena. A similar phenomenon is found in intestinal stem cells (ISCs), except that HSD disrupts ISC maintenance and differentiation. Interestingly, tumor-like GSCs and ISCs are less responsive to HSD, which may be because of their dependence on glycolytic metabolism and high energy demand, respectively. This study suggests that excess dietary sugar induces oxidative stress and damages stem cells before insulin resistance develops, a mechanism that may also occur in higher organisms.


Asunto(s)
Células Madre Adultas , Diabetes Mellitus Tipo 2 , Proteínas de Drosophila , Resistencia a la Insulina , Animales , Femenino , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Azúcares de la Dieta/metabolismo , Células Madre Adultas/metabolismo , Células Madre Neoplásicas/metabolismo , Obesidad
2.
Development ; 145(7)2018 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-29549109

RESUMEN

Diet is an important regulator of stem cell homeostasis; however, the underlying mechanisms of this regulation are not fully known. Here, we report that insulin signaling mediates dietary maintenance of Drosophila ovarian germline stem cells (GSCs) by promoting the extension of niche escort cell (EC) membranes to wrap around GSCs. This wrapping may facilitate the delivery of bone morphogenetic protein stemness factors from ECs in the niche to GSCs. In addition to the effects on GSCs, insulin signaling-mediated regulation of EC number and protrusions controls the division and growth of GSC progeny. The effects of insulin signaling on EC membrane extension are, at least in part, driven by enhanced translation of Failed axon connections (Fax) via Ribosomal protein S6 kinase. Fax is a membrane protein that may participate in Abelson tyrosine kinase-regulated cytoskeletal dynamics and is known to be involved in axon bundle formation. Therefore, we conclude that dietary cues stimulate insulin signaling in the niche to regulate EC cellular structure, probably via Fax-dependent cytoskeleton remodeling. This mechanism enhances intercellular contact and facilitates homeostatic interactions between somatic and germline cells in response to diet.


Asunto(s)
Extensiones de la Superficie Celular/fisiología , Dieta , Células Germinativas/fisiología , Homeostasis/fisiología , Insulina/metabolismo , Nicho de Células Madre/fisiología , Animales , Western Blotting , Supervivencia Celular/fisiología , Señales (Psicología) , Drosophila/citología , Drosophila/metabolismo , Drosophila/fisiología , Proteínas de Drosophila/metabolismo , Femenino , Técnica del Anticuerpo Fluorescente , Células Germinativas/citología , Células Germinativas/metabolismo , Ovario/metabolismo , Ovario/fisiología , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción de Señal
3.
J Biomed Sci ; 25(1): 67, 2018 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-30176860

RESUMEN

Ubiquitination modulates a large repertoire of cellular functions and thus, dysregulation of the ubiquitin system results in multiple human diseases, including cancer. Ubiquitination requires an E3 ligase, which is responsible for substrate recognition and conferring specificity to ubiquitination. HUWE1 is a multifaceted HECT domain-containing ubiquitin E3 ligase, which catalyzes both mono-ubiquitination and K6-, K48- and K63-linked poly-ubiquitination of its substrates. Many of the substrates of HUWE1 play a crucial role in maintaining the homeostasis of cellular development. Not surprisingly, dysregulation of HUWE1 is associated with tumorigenesis and metastasis. HUWE1 is frequently overexpressed in solid tumors, but can be downregulated in brain tumors, suggesting that HUWE1 may possess differing cell-specific functions depending on the downstream targets of HUWE1. This review introduces some important discoveries of the HUWE1 substrates, including those controlling proliferation and differentiation, apoptosis, DNA repair, and responses to stress. In addition, we review the signaling pathways HUWE1 participates in and obstacles to the identification of HUWE1 substrates. We also discuss up-to-date potential therapeutic designs using small molecules or ubiquitin variants (UbV) against the HUWE1 activity. These molecular advances provide a translational platform for future bench-to-bed studies. HUWE1 is a critical ubiquitination modulator during the tumor progression and may serve as a possible therapeutic target for cancer treatment.


Asunto(s)
Carcinogénesis/genética , Proteínas Supresoras de Tumor/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación , Apoptosis/genética , Proliferación Celular/genética , Daño del ADN/genética , Reparación del ADN/genética , Humanos , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo
4.
Dev Biol ; 414(2): 142-8, 2016 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27141871

RESUMEN

Epithelial stem cells undergo constant self-renewal and differentiation to maintain the homeostasis of epithelial tissues that undergo rapid turnover. Recent studies have shown that the epithelial-mesenchymal transition (EMT), which is primarily mediated by Snail via the suppression of E-cadherin, is able to generate cells with stem cell properties. However, the role of Snail in epithelial stem cells remains unclear. Here, we report that Snail directly controls proliferation of follicle stem cells (FSCs) in Drosophila females. Disruption of Snail expression in FSCs compromises their proliferation, but not their maintenance. Conversely, FSCs with excessive Snail expression display increased proliferation and lifespan, which is accompanied by a moderate decrease in the expression of E-cadherin (required for adhesion of FSCs to their niche) at the junction between their adjacent cells, indicating a conserved role of Snail in E-cadherin inhibition, which promote epithelial cell proliferation. Interestingly, a decrease in E-cadherin in snail-knock down FSCs does not restore the decreased proliferation of snail-knock down FSCs, suggesting that adhesion strength of FSCs to their niche is dispensable for Snail-mediated FSC division. Our results demonstrate that Snail controls epithelial stem cell division independently of its known role in the EMT, which contributes to induction of cancer stem cells.


Asunto(s)
Cadherinas/biosíntesis , Proteínas de Drosophila/biosíntesis , Folículo Ovárico/citología , Ovario/citología , Factores de Transcripción de la Familia Snail/fisiología , Células Madre/citología , Animales , Cadherinas/genética , Adhesión Celular , División Celular , Senescencia Celular , Proteínas de Drosophila/genética , Drosophila melanogaster/citología , Drosophila melanogaster/genética , Células Epiteliales/citología , Transición Epitelial-Mesenquimal/fisiología , Femenino , Regulación del Desarrollo de la Expresión Génica , Técnicas de Silenciamiento del Gen , Proteínas Luminiscentes/análisis , Mosaicismo , Factores de Transcripción de la Familia Snail/deficiencia , Nicho de Células Madre
5.
Am J Respir Crit Care Med ; 193(7): 753-66, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26583948

RESUMEN

RATIONALE: Despite the fact that tyrosine kinase inhibitors (TKIs) have been found effective in treating patients harboring activating mutations of epidermal growth factor receptor (EGFR), an acquired secondary mutation, T790M, which lowers the affinity to TKIs, can lead to EGFR TKI resistance after this standard treatment. OBJECTIVES: To evaluate the effect of small molecule T315 on EGFR degradation and its therapeutic efficacy in vitro and in vivo. METHODS: Lung adenocarcinoma cells were treated with T315, and cell proliferation and apoptotic proportion were determined by the CellTiter 96 AQueous MTS (3-[4,5-dimethylthiazol-2-yl]-5-[3-carboxymethoxyphenyl]-2-[4-sulfophenyl]-2H-tetrazolium, inner salt) assay and flow cytometry. The effects of T315 on EGFR mRNA and protein levels, autophosphorylation, ubiquitination, and degradation were evaluated by real-time polymerase chain reaction and Western blot, respectively. Direct targeting of T315 to EGFR was confirmed by the in vitro kinase assay and mass spectrometry. Finally, the preclinical effect of T315 was validated in the murine xenograft model in combination with a second-generation TKI, afatinib. MEASUREMENTS AND MAIN RESULTS: We identified T315 as a novel, potent small molecule for suppressing cancer cell proliferation in vitro and in vivo. The therapeutic effect was verified after T315 was combined with a second-generation TKI, afatinib, compared with a single drug administration. We found a new mechanism of action, in that T315 appears to directly bind EGFR and triggers EGFR-Y1045 autophosphorylation, whereby its degradation is triggered through the ubiquitin-proteasome pathway. CONCLUSIONS: Our evidence suggests that T315 is a novel class of anticancer drug that is able to inhibit the growth of EGFR-TKI-resistant lung adenocarcinoma cells by inducing the degradation of EGFR.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Resistencia a Antineoplásicos/efectos de los fármacos , Receptores ErbB/antagonistas & inhibidores , Neoplasias Pulmonares/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Quinazolinas/uso terapéutico , Proteínas Adaptadoras Transductoras de Señales/efectos de los fármacos , Proteínas Adaptadoras Transductoras de Señales/genética , Adenocarcinoma/genética , Adenocarcinoma del Pulmón , Afatinib , Animales , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Western Blotting , Proliferación Celular/efectos de los fármacos , Combinación de Medicamentos , Pruebas de Enzimas , Receptores ErbB/efectos de los fármacos , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/genética , Espectrometría de Masas , Ratones , Mutación/genética , Inhibidores de Proteínas Quinasas/efectos adversos , Proteínas Proto-Oncogénicas c-cbl/efectos de los fármacos , Proteínas Proto-Oncogénicas c-cbl/genética , Quinazolinas/efectos adversos , Reacción en Cadena en Tiempo Real de la Polimerasa , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
6.
PLoS Genet ; 10(12): e1004888, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25521289

RESUMEN

Stem cells have an innate ability to occupy their stem cell niche, which in turn, is optimized to house stem cells. Organ aging is associated with reduced stem cell occupancy in the niche, but the mechanisms involved are poorly understood. Here, we report that Notch signaling is increased with age in Drosophila female germline stem cells (GSCs), and this results in their removal from the niche. Clonal analysis revealed that GSCs with low levels of Notch signaling exhibit increased adhesiveness to the niche, thereby out-competing their neighbors with higher levels of Notch; adhesiveness is altered through regulation of E-cadherin expression. Experimental enhancement of Notch signaling in GSCs hastens their age-dependent loss from the niche, and such loss is at least partially mediated by Sex lethal. However, disruption of Notch signaling in GSCs does not delay GSC loss during aging, and nor does it affect BMP signaling, which promotes self-renewal of GSCs. Finally, we show that in contrast to GSCs, Notch activation in the niche (which maintains niche integrity, and thus mediates GSC retention) is reduced with age, indicating that Notch signaling regulates GSC niche occupancy both intrinsically and extrinsically. Our findings expose a novel role of Notch signaling in controlling GSC-niche adhesion in response to aging, and are also of relevance to metastatic cancer cells, in which Notch signaling suppresses cell adhesion.


Asunto(s)
Adhesión Celular , Proteínas de Drosophila/fisiología , Receptores Notch/fisiología , Nicho de Células Madre , Células Madre/fisiología , Envejecimiento , Animales , Proteínas Morfogenéticas Óseas/fisiología , Proteínas Cdh1/metabolismo , Proliferación Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citología , Femenino , Proteínas de Unión al ARN/fisiología , Transducción de Señal
7.
J Biol Chem ; 290(50): 29808-19, 2015 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-26475862

RESUMEN

Wnt/ß-catenin signaling controls various cell fates in metazoan development, and its dysregulation is often associated with cancer formation. However, regulations of this signaling pathway are not completely understood. Here, we report that Lzap, a tumor suppressor, controls nuclear translocation of ß-catenin. In zebrafish embryos disruption of lzap increases the expression of chordin (chd), which encodes a bone morphogenetic protein (BMP) antagonist that is localized in prospective dorsal cells and promotes dorsal fates. Consistently, lzap-deficient embryos with attenuated BMP signaling are dorsalized, which can be rescued by overexpression of zebrafish lzap or bmp2b or human LZAP. The expansion of chd expression in embryos lacking lzap is due to the accumulation of nuclear ß-catenin in ventral cells, in which ß-catenin is usually degraded. Furthermore, the activity of GSK3, a master regulator of ß-catenin degradation, is suppressed in lzap-deficient embryos via inhibitory phosphorylation. Finally, we also report that a similar regulatory axis is also likely to be present in a human tongue carcinoma cell line, SAS. Our results reveal that Lzap is a novel regulator of GSK3 for the maintenance of ventral cell properties and may prevent carcinogenesis via the regulation of ß-catenin degradation.


Asunto(s)
Genes Supresores de Tumor , Glucógeno Sintasa Quinasa 3/metabolismo , Transducción de Señal , Proteínas Supresoras de Tumor/fisiología , Proteínas Wnt/metabolismo , Proteínas de Pez Cebra/fisiología , Pez Cebra/embriología , beta Catenina/metabolismo , Animales , Linaje de la Célula , Fosforilación
8.
PLoS One ; 19(5): e0302653, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38748750

RESUMEN

Out-of-hospital cardiac arrest (OHCA) affects over 360,000 adults in the United States each year with a 50-80% mortality prior to reaching medical care. Despite aggressive supportive care and targeted temperature management (TTM), half of adults do not live to hospital discharge and nearly one-third of survivors have significant neurologic injury. The current treatment approach following cardiac arrest resuscitation consists primarily of supportive care and possible TTM. While these current treatments are commonly used, mortality remains high, and survivors often develop lasting neurologic and cardiac sequela well after resuscitation. Hence, there is a critical need for further therapeutic development of adjunctive therapies. While select therapeutics have been experimentally investigated, one promising agent that has shown benefit is CO. While CO has traditionally been thought of as a cellular poison, there is both experimental and clinical evidence that demonstrate benefit and safety in ischemia with lower doses related to improved cardiac/neurologic outcomes. While CO is well known for its poisonous effects, CO is a generated physiologically in cells through the breakdown of heme oxygenase (HO) enzymes and has potent antioxidant and anti-inflammatory activities. While CO has been studied in myocardial infarction itself, the role of CO in cardiac arrest and post-arrest care as a therapeutic is less defined. Currently, the standard of care for post-arrest patients consists primarily of supportive care and TTM. Despite current standard of care, the neurological prognosis following cardiac arrest and return of spontaneous circulation (ROSC) remains poor with patients often left with severe disability due to brain injury primarily affecting the cortex and hippocampus. Thus, investigations of novel therapies to mitigate post-arrest injury are clearly warranted. The primary objective of this proposed study is to combine our expertise in swine models of CO and cardiac arrest for future investigations on the cellular protective effects of low dose CO. We will combine our innovative multi-modal diagnostic platform to assess cerebral metabolism and changes in mitochondrial function in swine that undergo cardiac arrest with therapeutic application of CO.


Asunto(s)
Monóxido de Carbono , Modelos Animales de Enfermedad , Animales , Porcinos , Monóxido de Carbono/farmacología , Monóxido de Carbono/metabolismo , Paro Cardíaco/terapia , Paro Cardíaco Extrahospitalario/terapia , Masculino , Reanimación Cardiopulmonar/métodos
10.
Biomedicines ; 11(7)2023 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-37509447

RESUMEN

Traumatic brain injury (TBI) results in the generation of tau. As hyperphosphorylated tau (p-tau) is one of the major consequences of TBI, targeting p-tau in TBI may lead to the development of new therapy. Twenty-five pigs underwent a controlled cortical impact. One hour after TBI, pigs were administered either vehicle (n = 13) or PNT001 (n = 12), a monoclonal antibody for the cis conformer of tau phosphorylated at threonine 231. Plasma biomarkers of neural injury were assessed for 14 days. Diffusion tensor imaging was performed at day 1 and 14 after injury, and these were compared to historical control animals (n = 4). The fractional anisotropy data showed significant white matter injury for groups at 1 day after injury in the corona radiata. At 14 days, the vehicle-treated pigs, but not the PNT001-treated animals, exhibited significant white matter injury compared to sham pigs in the ipsilateral corona radiata. The PNT001-treated pigs had significantly lower levels of plasma glial fibrillary acidic protein (GFAP) at day 2 and day 4. These findings demonstrate a subtle reduction in the areas of white matter injury and biomarkers of neurological injury after treatment with PNT001 following TBI. These findings support additional studies for PNT001 as well as the potential use of this agent in clinical trials in the near future.

11.
J Med Toxicol ; 19(4): 352-361, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37523031

RESUMEN

INTRODUCTION: Organophosphates (OPs) are a major public health problem worldwide due to ease of access and high toxicity lacking effective biomarkers and treatment. Cholinergic agents such as OPs and carbamates are responsible for many pesticide-related deaths. While the inhibition of AChE is thought to be the main mechanism of injury, there are other important pathways that contribute to the overall toxicity of OPs such as mitochondrial dysfunction. An existing gap in OP poisoning are biomarkers to gauge severity and prognosis. Cell-free DNA (cfDNA) are novel biomarkers that have gained increased attention as a sensitive biomarker of disease with novel use in acute poisoning. This study investigates alterations in cerebral mitochondrial function in a rodent model of chlorpyrifos poisoning with the use of cfDNA as a potential biomarker. METHODS: Twenty rodents were divided into two groups: Control (n = 10) and Chlorpyrifos (n = 10). Chlorpyrifos was administered through the venous femoral line with a Harvard Apparatus 11 Elite Syringe pump (Holliston, MA, USA) at 2 mg/kg. Animals were randomized to receive chlorpyrifos versus the vehicle (10% DMSO) for 60 min which would realistically present an acute exposure with continued absorption. At the end of the exposure (60 min), isolated mitochondria were measured for mitochondrial respiration along with measures of acetylcholinesterase activity, cfDNA, cytokines and western blot. RESULTS: The Chlorpyrifos group showed a significant decrease in heart rate but no change in the blood pressure. There was a significant increase in bulk cfDNA concentrations and overall decrease in mitochondrial respiration from brain tissue obtained from animals in the Chlorpyrifos group when compared to the Control group with no difference in acetylcholinesterase activity. In addition, there was a significant increase in both IL-2 and IL-12 in the Chlorpyrifos group. CONCLUSIONS: In our study, we found that the total cfDNA concentration may serve as a more accurate biomarker of OP exposure compared to acetylcholinesterase activity. In addition, there was an overall decrease in cerebral mitochondrial function in the Chlorpyrifos group when compared to the Control group.


Asunto(s)
Cloropirifos , Animales , Acetilcolinesterasa/metabolismo , Biomarcadores , Cloropirifos/toxicidad , Inhibidores de la Colinesterasa/toxicidad , Mitocondrias/metabolismo , Roedores/metabolismo
12.
J Med Toxicol ; 19(2): 196-204, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36757579

RESUMEN

INTRODUCTION: Cyanide exposure can occur in various settings such as industry and metallurgy. The primary mechanism of injury is cellular hypoxia from Complex IV (CIV) inhibition. This leads to decreased ATP production and increased reactive oxygen species production. The brain and the heart are the organs most affected due to their high metabolic demand. While the cardiac effects of cyanide are well known, the cerebral effects on cellular function are less well described. We investigated cerebral metabolism with a combination of brain respirometry, microdialysis, and western blotting using a rodent model of sub-lethal cyanide poisoning. METHODS: Twenty rodents were divided into two groups: control (n = 10) and sub-lethal cyanide (n = 10). Cerebral microdialysis was performed during a 2 mg/kg/h cyanide exposure to obtain real-time measurements of cerebral metabolic status. At the end of the exposure (90 min), brain-isolated mitochondria were measured for mitochondrial respiration. Brain tissue ATP concentrations, acyl-Coenzyme A thioesters, and mitochondrial content were also measured. RESULTS: The cyanide group showed significantly increased lactate and decreased hypotension with decreased cerebral CIV-linked mitochondrial respiration. There was also a significant decrease in cerebral ATP concentration in the cyanide group and a significantly higher cerebral lactate-to-pyruvate ratio (LPR). In addition, we also found decreased expression of Complex III and IV protein expression in brain tissue from the cyanide group. Finally, there was no change in acyl-coenzyme A thioesters between the two groups. CONCLUSIONS: The key finding demonstrates mitochondrial dysfunction in brain tissue that corresponds with a decrease in mitochondrial function, ATP concentrations, and an elevated LPR indicating brain dysfunction at a sub-lethal dose of cyanide.


Asunto(s)
Cianuros , Roedores , Animales , Complejo IV de Transporte de Electrones , Lactatos , Adenosina Trifosfato , Coenzima A
13.
Sci Adv ; 9(14): eade9944, 2023 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-37027467

RESUMEN

Immune checkpoint inhibitors (ICIs) targeting PD-L1 immunotherapy are state-of-the-art treatments for advanced non-small cell lung cancer (NSCLC). However, the treatment response of certain patients with NSCLC is unsatisfactory because of an unfavorable tumor microenvironment (TME) and poor permeability of antibody-based ICIs. In this study, we aimed to discover small-molecule drugs that can modulate the TME to enhance ICI treatment efficacy in NSCLC in vitro and in vivo. We identified a PD-L1 protein-modulating small molecule, PIK-93, using a cell-based global protein stability (GPS) screening system. PIK-93 mediated PD-L1 ubiquitination by enhancing the PD-L1-Cullin-4A interaction. PIK-93 reduced PD-L1 levels on M1 macrophages and enhanced M1 antitumor cytotoxicity. Combined PIK-93 and anti-PD-L1 antibody treatment enhanced T cell activation, inhibited tumor growth, and increased tumor-infiltrating lymphocyte (TIL) recruitment in syngeneic and human peripheral blood mononuclear cell (PBMC) line-derived xenograft mouse models. PIK-93 facilitates a treatment-favorable TME when combined with anti-PD-L1 antibodies, thereby enhancing PD-1/PD-L1 blockade cancer immunotherapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Animales , Ratones , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Microambiente Tumoral , Linfocitos Infiltrantes de Tumor
14.
Biomed Opt Express ; 14(6): 2432-2448, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37342705

RESUMEN

In this study, we used diffuse optics to address the need for non-invasive, continuous monitoring of cerebral physiology following traumatic brain injury (TBI). We combined frequency-domain and broadband diffuse optical spectroscopy with diffuse correlation spectroscopy to monitor cerebral oxygen metabolism, cerebral blood volume, and cerebral water content in an established adult swine-model of impact TBI. Cerebral physiology was monitored before and after TBI (up to 14 days post injury). Overall, our results suggest that non-invasive optical monitoring can assess cerebral physiologic impairments post-TBI, including an initial reduction in oxygen metabolism, development of cerebral hemorrhage/hematoma, and brain swelling.

15.
bioRxiv ; 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37503137

RESUMEN

Background: Pediatric neurological injury and disease is a critical public health issue due to increasing rates of survival from primary injuries (e.g., cardiac arrest, traumatic brain injury) and a lack of monitoring technologies and therapeutics for the treatment of secondary neurological injury. Translational, preclinical research facilitates the development of solutions to address this growing issue but is hindered by a lack of available data frameworks and standards for the management, processing, and analysis of multimodal data sets. Methods: Here, we present a generalizable data framework that was implemented for large animal research at the Children's Hospital of Philadelphia to address this technological gap. The presented framework culminates in an interactive dashboard for exploratory analysis and filtered data set download. Results: Compared with existing clinical and preclinical data management solutions, the presented framework accommodates heterogeneous data types (single measure, repeated measures, time series, and imaging), integrates data sets across various experimental models, and facilitates dynamic visualization of integrated data sets. We present a use case of this framework for predictive model development for intra-arrest prediction of cardiopulmonary resuscitation outcome. Conclusions: The described preclinical data framework may serve as a template to aid in data management efforts in other translational research labs that generate heterogeneous data sets and require a dynamic platform that can easily evolve alongside their research.

16.
Biol Proced Online ; 14: 2, 2012 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-22304896

RESUMEN

BACKGROUND: It is widely understood that tumor cells express tumor-associated antigens (TAAs), of which many are usually in low immunogenicity; for example, carcinoembryonic antigen (CEA) is specifically expressed on human colon cancer cells and is viewed as a low-immunogenic TAA. How to activate host immunity against specific TAAs and to suppress tumor growth therefore becomes important in cancer therapy development. RESULTS: To enhance the immune efficiency of CEA in mice that received, we fused a partial CEA gene with exogenous SARS-CoV fragments. Oral vaccination of an attenuated Salmonella typhimurium strain transformed with plasmids encoding CEA-SARS-CoV fusion gene into BALB/c mice elicited significant increases in TNF-α and IL-10 in the serum. In addition, a smaller tumor volume was observed in CT26/CEA-bearing mice who received CEA-SARS-CoV gene therapy in comparison with those administered CEA alone. CONCLUSION: The administration of fusing CEA-SARS-CoV fragments may provide a promising strategy for strengthening the anti-tumor efficacy against low-immunogenic endogenous tumor antigens.

17.
Adv Biol (Weinh) ; 6(6): e2101325, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35362269

RESUMEN

Dynamic extracellular environments profoundly affect the behavior and function of cells both biochemically and mechanically. Neurite initiation is the first step for neurons to establish intricate neuronal networks. How such a process is modulated by mechanical factors is not fully understood. Particularly, it is unknown whether the molecular clutch model, which has been used to explain cell responses to matrix rigidity, also holds for neurite initiation. To study how mechanical properties modulate neurite initiation, substrates with various well-defined surface viscosities using supported lipid bilayers (SLBs) are synthesized. The results show that ligands with intermediate viscosity greatly maximize neurite initiation in primary neurons, while neurite initiation is drastically limited on substrates with higher or lower viscosity. Importantly, biochemical characterizations reveal altered focal adhesion and calpain activity are associated with distinct neurite initiation patterns. Collectively, these results indicate that neurite initiation is surface viscosity-dependent; there is an optimal range of surface viscosities to drive neurite initiation. Upon binding to ligands of varying viscosities, calpain activity is differentially triggered and leads to distinct levels of neurite outgrowth. These findings not only enhance the understanding of how extracellular environments regulate neurons, but also demonstrate the potential utility of SLBs for neural tissue engineering applications.


Asunto(s)
Calpaína , Neuritas , Ligandos , Membrana Dobles de Lípidos/química , Neuritas/fisiología , Neuronas , Viscosidad
18.
J Med Toxicol ; 18(3): 214-222, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35482181

RESUMEN

INTRODUCTION: Carbon monoxide (CO) is a colorless and odorless gas that is a leading cause of environmental poisoning in the USA with substantial mortality and morbidity. The mechanism of CO poisoning is complex and includes hypoxia, inflammation, and leukocyte sequestration in brain microvessel segments leading to increased reactive oxygen species. Another important pathway is the effects of CO on the mitochondria, specifically at cytochrome c oxidase, also known as Complex IV (CIV). The purpose of this ongoing study is the preliminary development of a porcine model of CO poisoning for investigation of alterations in brain mitochondrial physiology. METHODS: Four pigs (10 kg) were divided into two groups: Sham (n = 2) and CO (n = 2). Administration of a dose of CO at 2000 ppm to the CO group over 120 minutes followed by 30 minutes of re-oxygenation at room air. The control group received room air for 150 minutes. Non-invasive optical monitoring was used to measure CIV redox states. Cerebral microdialysis was performed to obtain semi real-time measurements of cerebral metabolic status. At the end of the exposure, fresh brain tissue (cortical and hippocampal) was immediately harvested to measure mitochondrial respiration. Snap frozen cortical tissue was also used for ATP concentrations and western blotting. RESULTS: While a preliminary ongoing study, animals in the CO group showed possible early decreases in brain mitochondrial respiration, citrate synthase density, CIV redox changes measured with optics, and an increase in the lactate-to-pyruvate ratio. CONCLUSIONS: There is a possible observable phenotype highlighting the important role of mitochondrial function in the injury of CO poisoning.


Asunto(s)
Intoxicación por Monóxido de Carbono , Animales , Monóxido de Carbono/metabolismo , Intoxicación por Monóxido de Carbono/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Humanos , Mitocondrias/metabolismo , Oxidación-Reducción , Porcinos
19.
Cells ; 10(12)2021 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-34943968

RESUMEN

Neurodegenerative disorders that are triggered by injury typically have variable and unpredictable outcomes due to the complex and multifactorial cascade of events following the injury and during recovery. Hence, several factors beyond the initial injury likely contribute to the disease progression and pathology, and among these are genetic factors. Genetics is a recognized factor in determining the outcome of common neurodegenerative diseases. The role of mitochondrial genetics and function in traditional neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases, is well-established. Much less is known about mitochondrial genetics, however, regarding neurodegenerative diseases that result from injuries such as traumatic brain injury and ischaemic stroke. We discuss the potential role of mitochondrial DNA genetics in the progression and outcome of injury-related neurodegenerative diseases. We present a guide for understanding mitochondrial genetic variation, along with the nuances of quantifying mitochondrial DNA variation. Evidence supporting a role for mitochondrial DNA as a risk factor for neurodegenerative disease is also reviewed and examined. Further research into the impact of mitochondrial DNA on neurodegenerative disease resulting from injury will likely offer key insights into the genetic factors that determine the outcome of these diseases together with potential targets for treatment.


Asunto(s)
Lesiones Traumáticas del Encéfalo/genética , ADN Mitocondrial/genética , Mitocondrias/genética , Accidente Cerebrovascular/genética , Lesiones Traumáticas del Encéfalo/patología , Variación Genética/genética , Humanos , Factores de Riesgo , Accidente Cerebrovascular/patología
20.
Life (Basel) ; 11(5)2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33946374

RESUMEN

Sepsis develops from a serious microbial infection that causes the immune system to go into overdrive. The major microorganisms that induce sepsis are Gram-negative bacteria with lipopolysaccharide (LPS) in their cell walls. Nitric oxide (NO) and cyclooxygenase-2 (COX-2) are the key factors involved in the LPS-induced pro-inflammatory process. This study aimed to evaluate the effects of polyphenol Tellimagrandin II (TGII) on anti-inflammatory activity and its underlying basic mechanism in murine macrophage cell line RAW 264.7 and human monocyte-derived macrophages. Macrophages with more than 90% cell viability were found in the cytotoxicity assay under 50 µM TGII. Pre- or post-treatment with TGII significantly reduced LPS-induced inducible nitric oxide synthase (NOS2) protein and mRNA expression, reducing LPS-induced COX-2 protein. Downstream of NOS2 and COX-2, NO and prostaglandin E2 (PGE2) were significantly inhibited by TGII. Upstream of NOS2 and COX-2, phospho-p65, c-fos and phospho-c-jun were also reduced after pre-treatment with TGII. Mitogen-activated protein kinases (MAPKs) are also critical to nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) stimulation, and phospho-p38 expression was found to have been blocked by TGII. TGII efficiently reduces LPS-induced NO production and its upstream regulatory factors, suggesting that TGII may be a potential therapeutic agent for sepsis and other inflammatory diseases.

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