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1.
J Infect Dis ; 228(Suppl 4): S291-S296, 2023 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-37788499

RESUMEN

BACKGROUND: Microbial-based cancer treatments are an emerging field, with multiple bacterial species evaluated in animal models and some advancing to clinical trials. Noninvasive bacteria-specific imaging approaches can potentially support the development and clinical translation of bacteria-based cancer treatments by assessing the tumor and off-target bacterial colonization. METHODS: 18F-Fluorodeoxysorbitol (18F-FDS) positron emission tomography (PET), a bacteria-specific imaging approach, was used to visualize an attenuated strain of Yersinia enterocolitica, currently in clinical trials as a microbial-based cancer treatment, in murine models of breast cancer. RESULTS: Y. enterocolitica demonstrated excellent 18F-FDS uptake in in vitro assays. Whole-body 18F-FDS PET demonstrated a significantly higher PET signal in tumors with Y. enterocolitica colonization compared to those not colonized, in murine models utilizing direct intratumor or intravenous administration of bacteria, which were confirmed using ex vivo gamma counting. Conversely, 18F-fluorodeoxyglucose (18F-FDG) PET signal was not different in Y. enterocolitica colonized versus uncolonized tumors. CONCLUSIONS: Given that PET is widely used for the management of cancer patients, 18F-FDS PET could be utilized as a complementary approach supporting the development and clinical translation of Y. enterocolitica-based tumor-targeting bacterial therapeutics.


Asunto(s)
Neoplasias , Tomografía de Emisión de Positrones , Humanos , Ratones , Animales , Tomografía de Emisión de Positrones/métodos , Radioisótopos de Flúor , Neoplasias/diagnóstico por imagen , Neoplasias/terapia , Fluorodesoxiglucosa F18 , Radiofármacos
2.
Sensors (Basel) ; 21(11)2021 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-34199899

RESUMEN

In a 3D scanning system, using a camera and a line laser, it is critical to obtain the exact geometrical relationship between the camera and laser for precise 3D reconstruction. With existing depth cameras, it is difficult to scan a large object or multiple objects in a wide area because only a limited area can be scanned at a time. We developed a 3D scanning system with a rotating line laser and wide-angle camera for large-area reconstruction. To obtain 3D information of an object using a rotating line laser, we must be aware of the plane of the line laser with respect to the camera coordinates at every rotating angle. This is done by estimating the rotation axis during calibration and then by rotating the laser at a predefined angle. Therefore, accurate calibration is crucial for 3D reconstruction. In this study, we propose a calibration method to estimate the geometrical relationship between the rotation axis of the line laser and the camera. Using the proposed method, we could accurately estimate the center of a cone or cylinder shape generated while the line laser was rotating. A simulation study was conducted to evaluate the accuracy of the calibration. In the experiment, we compared the results of the 3D reconstruction using our system and a commercial depth camera. The results show that the precision of our system is approximately 65% higher for plane reconstruction, and the scanning quality is also much better than that of the depth camera.

3.
Biomacromolecules ; 21(2): 892-902, 2020 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-31895978

RESUMEN

Here, we report the striking properties such as high stretchability, self-healing, and adhesiveness of an amphiphilic copolymeric hydrogel (poly(acrylic acid)-poly(methyl methacrylate) (PAA-PMMA) gel) synthesized from two immiscible monomers-acrylic acid (AA) and methyl methacrylate (MMA)-through a simple free radical polymerization in an aqueous medium. The developed hydrogel, with a specific molar ratio of MMA and AA, is self-healable, which is attributed to the hydrophobic interaction arising from methyl groups of PMMA, as well as the breakdown and reformation of sacrificial noncovalent cross-linking through the weak hydrogen bonds between the carboxylic acid groups of PAA and methoxy groups of PMMA. The energy dissipation values in the hysteresis test signify the excellent self-recoverability of the hydrogel. The developed hydrogel showed adhesive behavior to the surfaces of polystyrene, glass, wood, metal, stone, ceramics, pork skin, and human skin. The physical and mechanical properties of the PAA-PMMA gel were fine-tuned through changes in the MMA/AA ratio and pH. Moreover, the PAA-PMMA hydrogel can serve as a template for calcium phosphate mineralization to yield a hydrogel composite, which improved MC3T3 cell adhesion and proliferation. Overall, we propose that depending on synthesis parameters and other scenarios, the synthesized PAA-PMMA hydrogel could potentially be employed in varying biomedical and industrial applications.


Asunto(s)
Adhesivos/química , Proliferación Celular/fisiología , Desarrollo de Medicamentos/métodos , Hidrogeles/química , Polímeros/química , Tensoactivos/química , Resinas Acrílicas/química , Resinas Acrílicas/metabolismo , Adhesivos/metabolismo , Animales , Cloruro de Calcio/química , Cloruro de Calcio/metabolismo , Línea Celular , Hidrogeles/metabolismo , Ratones , Fosfatos/química , Fosfatos/metabolismo , Polimerizacion , Polímeros/metabolismo , Polimetil Metacrilato/química , Polimetil Metacrilato/metabolismo , Compuestos de Potasio/química , Compuestos de Potasio/metabolismo , Piel/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Tensoactivos/metabolismo , Porcinos
4.
Cancer Sci ; 110(2): 662-673, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30485589

RESUMEN

Cisplatin is a well-known anticancer drug used to treat various cancers. However, development of cisplatin resistance has hindered the efficiency of this drug in cancer treatment. Development of chemoresistance is known to involve many signaling pathways. Recent attention has focused on microRNAs (miRNAs) as potentially important upstream regulators in the development of chemoresistance. CD44 is one of the gastric cancer stem cell markers and plays a role in regulating self-renewal, tumor initiation, metastasis and chemoresistance. The purpose of the present study was to examine the mechanism of miRNA-mediated chemoresistance to cisplatin in CD44-positive gastric cancer stem cells. We sorted gastric cancer cells according to level of CD44 expression by FACS and analyzed their miRNA expression profiles by microarray analysis. We found that miR-193a-3p was significantly upregulated in CD44(+) cells compared with CD44(-) cells. Moreover, SRSF2 of miR-193a-3p target gene was downregulated in CD44(+) cells. We studied the modulation of Bcl-X and caspase 9 mRNA splicing by SRSF2 and found that more pro-apoptotic variants of these genes were generated. We also found that downstream anti-apoptotic genes such as Bcl-2 were upregulated, whereas pro-apoptotic genes such as Bax and cytochrome C were downregulated in CD44(+) cells compared to CD44(-) cells. In addition, we found that an elevated level of miR-193a-3p triggered the development of cisplatin resistance in CD44(+) cells. Inhibition of miR-193a-3p in CD44(+) cells increased SRSF2 expression and also altered the levels of multiple apoptotic genes. Furthermore, inhibition of miR-193a-3p reduced cell viability and increased the number of apoptotic cells. Therefore, miR-193a-3p may be implicated in the development of cisplatin resistance through regulation of the mitochondrial apoptosis pathway. miR-193a-3p could be a promising target for cancer therapy in cisplatin-resistant gastric cancer.


Asunto(s)
Cisplatino/farmacología , Receptores de Hialuranos/genética , MicroARNs/genética , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Regulación hacia Arriba/genética , Apoptosis/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación hacia Abajo/genética , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Proteínas Proto-Oncogénicas c-bcl-2/genética , Factores de Empalme Serina-Arginina/genética , Transducción de Señal/genética , Regulación hacia Arriba/efectos de los fármacos
5.
Biochem Biophys Res Commun ; 508(2): 430-439, 2019 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-30503340

RESUMEN

An organoid is a complex, multi-cell three-dimensional (3D) structure that contains tissue-specific cells. Epithelial stem cells, which are marked by leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5), have the potential for self-renewal and expansion as organoids. However, in the case of intestinal organoids from Lgr5-EGFP-IRES-CreERT2 transgenic mice, in vitro expansion of the Lgr5 expression is limited in a culture condition supplemented with essential proteins, such as epidermal growth factor (E), noggin (N), and R-spondin 1 (R). In this study, we hypothesized that self-renewal of Lgr5+ stem cells in a 3D culture system can be stimulated by defined compounds (CHIR99021, Valproic acid, Y-27632, and A83-01). Our results demonstrated that dissociated single cells from organoids were organized into a 3D structure in the four compounds containing the ENR culture medium in a 3D and two-dimensional (2D) culture system. Moreover, the Lgr5 expression level of organoids from the ENR- and compound-containing media increased. Furthermore, the conversion of cultured Lgr5+ stem cells from 2D to 3D was confirmed. Therefore, defined compounds promote the expansion of Lgr5+ stem cells in organoids.


Asunto(s)
Organoides/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Células Madre Adultas/citología , Células Madre Adultas/efectos de los fármacos , Células Madre Adultas/metabolismo , Amidas/farmacología , Animales , Autorrenovación de las Células/efectos de los fármacos , Autorrenovación de las Células/genética , Autorrenovación de las Células/fisiología , Medio de Cultivo Libre de Suero , Flavonoides/farmacología , Expresión Génica/efectos de los fármacos , Humanos , Mucosa Intestinal/citología , Mucosa Intestinal/metabolismo , Ratones , Ratones Transgénicos , Organoides/citología , Organoides/crecimiento & desarrollo , Pirazoles/farmacología , Piridinas/farmacología , Pirimidinas/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores Acoplados a Proteínas G/genética , Tiosemicarbazonas/farmacología , Ácido Valproico/farmacología
6.
Stem Cells ; 36(7): 1020-1032, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29569790

RESUMEN

To explore the effects and mechanisms of paracrine factors secreted from human adipose mesenchymal stem cell (hAdMSCs) that are activated by hypoxia on radioprotection against irradiation-induced salivary hypofunction in subjects undergoing radiotherapy for head and neck cancers. An organotypic spheroid coculture model to mimic irradiation (IR)-induced salivary hypofunction was set up for in vitro experiments. Human parotid gland epithelial cells were organized to form three-dimensional (3D) acinus-like spheroids on growth factor reduced -Matrigel. Cellular, structural, and functional damage following IR were examined after cells were cocultured with hAdMSCs preconditioned with either normoxia (hAdMSCNMX ) or hypoxia (hAdMSCHPX ). A key paracrine factor secreted by hAdMSCsHPX was identified by high-throughput microarray-based enzyme-linked immunosorbent assay. Molecular mechanisms and signaling pathways on radioprotection were explored. Therapeutic effects of hAdMSCsHPX were evaluated after in vivo transplant into mice with IR-induced salivary hypofunction. In our 3D coculture experiment, hAdMSCsHPX significantly enhanced radioresistance of spheroidal human parotid epithelial cells, and led to greater preservation of salivary epithelial integrity and acinar secretory function relative to hAdMSCsNMX . Coculture with hAdMSCsHPX promoted FGFR expression and suppressed FGFR diminished antiapoptotic activity of hAdMSCsHPX . Among FGFR-binding secreted factors, we found that fibroblast growth factor 10 (FGF10) contributed to therapeutic effects of hAdMSCsHPX by enhancing antiapoptotic effect, which was dependent on FGFR-PI3K signaling. An in vivo transplant of hAdMSCsHPX into irradiated salivary glands of mice reversed IR-induced salivary hypofunction where hAdMSC-released FGF10 contributed to tissue remodeling. Our results suggest that hAdMSCsHPX protect salivary glands from IR-induced apoptosis and preserve acinar structure and functions by activation of FGFR-PI3K signaling via actions of hAdMSC-secreted factors, including FGF10. Stem Cells 2018;36:1020-1032.


Asunto(s)
Factor 10 de Crecimiento de Fibroblastos/metabolismo , Células Madre Mesenquimatosas/metabolismo , Traumatismos Experimentales por Radiación/fisiopatología , Glándulas Salivales/efectos de la radiación , Animales , Hipoxia de la Célula , Células Cultivadas , Femenino , Humanos , Ratones , Glándulas Salivales/citología , Transfección
7.
Lab Invest ; 95(10): 1157-73, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26192086

RESUMEN

Epithelial-to-mesenchymal transition (EMT) and apoptosis of peritoneal mesothelial cells are known to be the earliest mechanisms of peritoneal fibrosis in peritoneal dialysis (PD). Endoplasmic reticulum (ER) stress with an unfolded protein response is regarded to have a role in the development of organ fibrosis. To investigate the potential role of ER stress as a target to prevent and/or delay the development of peritoneal fibrosis, we examined the effect of ER stress on EMT or apoptosis of human peritoneal mesothelial cells (HPMCs) and elucidated the mechanisms underlying the protective effect of ER stress preconditioning on TGF-ß1-induced EMT. ER stress inducers, tunicamycin (TM) and thapsigargin (TG), induced EMT with Smad2/3 phosphorylation, an increased nuclear translocation of ß-catenin and Snail expression. Low concentrations of TM and TG did not induce apoptosis within 48 h; however, high concentrations of TM- (>1 ng/ml) and TG- (>1 nM) induced apoptosis at 12 h with a persistent increase in C/EBP homologous protein. TGF-ß1 induced EMT and apoptosis in HPMCs, which was ameliorated by taurine-conjugated ursodeoxycholic acid, an ER stress blocker. Interestingly, pre-treatment with TM or TG for 4 h also protected the cells from TGF-ß1-induced EMT and apoptosis, demonstrating the role of ER stress as an adaptive response to protect HPMCs from EMT and apoptosis. Peritoneal mesothelial cells isolated from PD patients displayed an increase in GRP78/94, which was correlated with the degree of EMT. These findings suggest that the modulation of ER stress in HPMCs could serve as a novel approach to ameliorate peritoneal damage in PD patients.


Asunto(s)
Apoptosis , Estrés del Retículo Endoplásmico , Transición Epitelial-Mesenquimal , Modelos Biológicos , Diálisis Peritoneal/efectos adversos , Fibrosis Peritoneal/patología , Respuesta de Proteína Desplegada , Antibacterianos/efectos adversos , Líquido Ascítico/metabolismo , Líquido Ascítico/patología , Células Cultivadas , Chaperón BiP del Retículo Endoplásmico , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Moduladores del Transporte de Membrana/efectos adversos , Señales de Localización Nuclear/efectos de los fármacos , Señales de Localización Nuclear/metabolismo , Fibrosis Peritoneal/inducido químicamente , Fibrosis Peritoneal/etiología , Fibrosis Peritoneal/metabolismo , Fosforilación/efectos de los fármacos , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Proteína Smad2/metabolismo , Proteína smad3/metabolismo , Factores de Transcripción de la Familia Snail , Tapsigargina/efectos adversos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Tunicamicina/efectos adversos , beta Catenina/metabolismo
8.
Lab Invest ; 94(10): 1147-60, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25111692

RESUMEN

Aminoglycoside-induced nephrotoxicity is one of the prevalent causes of acute kidney injury (AKI). Oxidative stress-mediated apoptosis of renal tubular cells is known to be a major mechanism of renal injury. Red ginseng extract (RGE) has been reported to possess antioxidant and immune-modulatory activities. We investigated the effect of RGE on gentamicin (GM)-induced apoptosis and oxidative stress in cultured renal tubular cells and animal model of GM-induced AKI. GM induced the generation of reactive oxygen species (ROS) with an increase in NADPH oxidase (NOX) activity and mitochondrial oxidation in NRK-52E cells that were ameliorated with RGE. GM-induced apoptosis of NRK-52E cells, which was associated with an increased expression of mitochondrial Bax, cytosolic cytochrome c, and cleaved caspase-9 and -3, along with a decrease in bcl-2 expression, was also blocked by RGE. In an animal model of GM-induced AKI, RGE treatment significantly attenuated renal dysfunction, cell apoptosis, and tubular damage. RGE ameliorated ROS production in rats with GM-induced AKI, as demonstrated by an increase in the reduced form of glutathione in renal cortex and a decrease in urinary excretion of 8-hydroxy-2'-deoxyguanosine. Our results suggest that RGE protects the kidney from GM-induced AKI via the mechanism of modulation of oxidative stress.


Asunto(s)
Lesión Renal Aguda/prevención & control , Túbulos Renales/efectos de los fármacos , Panax , Fitoterapia , Extractos Vegetales/uso terapéutico , Lesión Renal Aguda/inducido químicamente , Animales , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Gentamicinas/efectos adversos , Masculino , NADPH Oxidasas/metabolismo , Extractos Vegetales/farmacología , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo
9.
Lab Invest ; 94(12): 1370-81, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25286029

RESUMEN

Cancer stem cells have the capacity to form new tumors and are thus considered to be a cause of metastasis and tumor recurrence. However, many of the mechanisms determining cancer stem cell characteristics are still unknown. MicroRNAs (miRNAs) are possible modulators of cancer stem cell generation and may be involved in the retention of cancer stem cell characteristics. The aim of this study was to examine the miRNA expression profiles regulating the cancer stem-like cell characteristics in gastric cancer. We sorted gastric cancer stem-like cells using the stem cell marker CD44 by fluorescence-activated cell sorting. CD44(+) cells formed more and larger spheres compared with CD44(-) cells. Cancer stem cell markers were overexpressed in CD44(+) cells. CD44(+) cells showed increased expression of mesenchymal cell markers, whereas epithelial markers were downregulated. In miRNA microarray, the miR-106b family comprising miR-106b, miR-93, and miR-25 was significantly upregulated in CD44(+) cells than in CD44(-) cells. Smad7, which inhibits transforming growth factor-ß (TGF-ß)/Smad signaling as a target of the miR-106b family, was downregulated in CD44(+) cells. Furthermore, expression of TGF-ß/Smad signal molecules was activated in CD44(+) cells, in accordance with the action of the miR-106b family. Inhibition of miR-106b showed suppression of the TGF-ß/Smad signaling pathway and decreased self-renewal capacity and cell invasiveness. Our study suggests that CD44(+) gastric cancer cells show cancer stem cell properties with epithelial-mesenchymal transition (EMT). Increased miR-106b family expression regulated cancer stem-like cell properties, particularly EMT characteristics, through the TGF-ß/Smad signaling pathway in CD44(+) stem-like cells. Taken together, these results indicate that targeting miR-106b may be an effective form of cancer therapy in gastric cancer through the modulation of cancer stem cell characteristics.


Asunto(s)
Receptores de Hialuranos/análisis , MicroARNs/fisiología , Células Madre Neoplásicas/patología , Transducción de Señal , Proteínas Smad/fisiología , Neoplasias Gástricas/patología , Factor de Crecimiento Transformador beta/fisiología , Línea Celular Tumoral , Transición Epitelial-Mesenquimal , Humanos , MicroARNs/antagonistas & inhibidores , Invasividad Neoplásica , Transducción de Señal/fisiología
10.
Lab Invest ; 94(10): 1114-25, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25111690

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is currently one of the most common types of chronic liver injury. Elevated serum uric acid is a strong predictor of the development of fatty liver as well as metabolic syndrome. Here we demonstrate that uric acid induces triglyceride accumulation by SREBP-1c activation via induction of endoplasmic reticulum (ER) stress in hepatocytes. Uric acid-induced ER stress resulted in an increase of glucose-regulated protein (GRP78/94), splicing of the X-box-binding protein-1 (XBP-1), the phosphorylation of protein kinase RNA-like ER kinase (PERK), and eukaryotic translation initiation factor-2α (eIF-2α) in cultured hepatocytes. Uric acid promoted hepatic lipogenesis through overexpression of the lipogenic enzyme, acetyl-CoA carboxylase 1 (ACC1), fatty acid synthase (FAS), and stearoyl-CoA desaturase 1 (SCD1) via activation of SREBP-1c, which was blocked by probenecid, an organic anion transport blocker in HepG2 cells and primary hepatocytes. A blocker of ER stress, tauroursodeoxycholic acid (TUDCA), and an inhibitor of SREBP-1c, metformin, blocked hepatic fat accumulation, suggesting that uric acid promoted fat synthesis in hepatocytes via ER stress-induced activation of SREBP-1c. Uric acid-induced activation of NADPH oxidase preceded ER stress, which further induced mitochondrial ROS production in hepatocytes. These studies provide new insights into the mechanisms by which uric acid stimulates fat accumulation in the liver.


Asunto(s)
Estrés del Retículo Endoplásmico , Hígado Graso/etiología , Lipogénesis , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Ácido Úrico/metabolismo , Acetil-CoA Carboxilasa/metabolismo , Animales , Chaperón BiP del Retículo Endoplásmico , Ácido Graso Sintasas/metabolismo , Células Hep G2 , Hepatocitos/metabolismo , Humanos , Ratones , Estearoil-CoA Desaturasa/metabolismo , Factores de Transcripción/metabolismo , Triglicéridos/metabolismo
11.
Mol Cell Biochem ; 396(1-2): 213-20, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25081334

RESUMEN

CD44 is a cell surface protein and it is widely used as a cancer stem cell marker in various cancer types including gastric cancer. We conducted proteomic analysis in CD44(+) and CD44(-) gastric cancer cells to understand characteristics of CD44(+) and CD44(-) cells. In the present study, we sorted cells from the gastric cancer cell line MKN45 according to CD44 expression to separate out CD44(+) and CD44(-) cells. And we conducted RT-PCR to identify mRNA expression of cancer stem cell markers in CD44(+) and CD44(-) cells. Cancer stem cell markers showed upregulated expression in CD44(+) cells. Next, we performed two-dimensional electrophoresis analysis to determine the differential expression pattern of proteins in each group; control, CD44(+), and CD44(-) MKN45 cells. We found a total of 113 spots that varied in expression between CD44(+) and CD44(-) cells, and subjected 20 of those protein spots to MALDI-MS. We selected the three proteins (HSPA8; heat shock cognate 71 kDa protein isoform 1, ezrin, α-enolase) upregulated in CD44(+) cells than CD44(-) cells and one protein (prohibitin) showed increased expression in CD44(-) cells. We validated the protein expression levels of four selected proteins by Western blot. We suggest that our study could be a helpful background to study CD44(+) cancer stem-like cells and differences between CD44(+) and CD44(-) cells in gastric cancer.


Asunto(s)
Receptores de Hialuranos/metabolismo , Proteínas/análisis , Neoplasias Gástricas/metabolismo , Biomarcadores de Tumor/metabolismo , Separación Celular , Proteínas del Citoesqueleto/metabolismo , Electroforesis en Gel Bidimensional , Perfilación de la Expresión Génica , Proteínas del Choque Térmico HSC70/metabolismo , Humanos , Células Madre Neoplásicas/metabolismo , Fosfopiruvato Hidratasa/metabolismo , Proteínas/genética , Proteínas/metabolismo , Proteómica/métodos , Reproducibilidad de los Resultados , Neoplasias Gástricas/patología , Regulación hacia Arriba
12.
Res Sq ; 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38559267

RESUMEN

Sleep disturbances are prevalent in children with autism spectrum disorder (ASD) and have a major impact on the quality of life. Strikingly, sleep problems are positively correlated with the severity of ASD symptoms, such as memory impairment. However, the neural mechanisms underlying sleep disturbances and cognitive deficits in ASD are largely unexplored. Here, we show that non-rapid eye movement sleep (NREMs) is highly fragmented in the 16p11.2 deletion mouse model of ASD. The degree of sleep fragmentation is reflected in an increased number of calcium transients in the activity of locus coeruleus noradrenergic (LC-NE) neurons during NREMs. Exposure to a novel environment further exacerbates sleep disturbances in 16p11.2 deletion mice by fragmenting NREMs and decreasing rapid eye movement sleep (REMs). In contrast, optogenetic inhibition of LC-NE neurons and pharmacological blockade of noradrenergic transmission using clonidine reverse sleep fragmentation. Furthermore, inhibiting LC-NE neurons restores memory. Rabies-mediated unbiased screening of presynaptic neurons reveals altered connectivity of LC-NE neurons with sleep- and memory regulatory brain regions in 16p11.2 deletion mice. Our findings demonstrate that heightened activity of LC-NE neurons and altered brain-wide connectivity underlies sleep fragmentation in 16p11.2 deletion mice and identify a crucial role of the LC-NE system in regulating sleep stability and memory in ASD.

13.
bioRxiv ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38234815

RESUMEN

Sleep disturbances are prevalent in children with autism spectrum disorder (ASD) and have a major impact on the quality of life. Strikingly, sleep problems are positively correlated with the severity of ASD symptoms, such as memory impairment. However, the neural mechanisms underlying sleep disturbances and cognitive deficits in ASD are largely unexplored. Here, we show that non-rapid eye movement sleep (NREMs) is highly fragmented in the 16p11.2 deletion mouse model of ASD. The degree of sleep fragmentation is reflected in an increased number of calcium transients in the activity of locus coeruleus noradrenergic (LC-NE) neurons during NREMs. Exposure to a novel environment further exacerbates sleep disturbances in 16p11.2 deletion mice by fragmenting NREMs and decreasing rapid eye movement sleep (REMs). In contrast, optogenetic inhibition of LC-NE neurons and pharmacological blockade of noradrenergic transmission using clonidine reverse sleep fragmentation. Furthermore, inhibiting LC-NE neurons restores memory. Rabies-mediated unbiased screening of presynaptic neurons reveals altered connectivity of LC-NE neurons with sleep- and memory regulatory brain regions in 16p11.2 deletion mice. Our findings demonstrate that heightened activity of LC-NE neurons and altered brain-wide connectivity underlies sleep fragmentation in 16p11.2 deletion mice and identify a crucial role of the LC-NE system in regulating sleep stability and memory in ASD.

14.
Am J Physiol Renal Physiol ; 304(5): F471-80, 2013 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23283992

RESUMEN

Recent experimental and clinical studies suggest a causal role of uric acid in the development of chronic kidney disease. Most studies have focused on uric acid-induced endothelial dysfunction, oxidative stress, and inflammation in the kidney. The direct effects of uric acid on tubular cells have not been studied in detail, and whether uric acid can mediate phenotypic transition of renal tubular cells such as epithelial-to-mesenchymal transition (EMT) is not known. We therefore investigated whether uric acid could alter E-cadherin expression and EMT in the kidney of hyperuricemic rats and in cultured renal tubular cells (NRK cells). Experimental hyperuricemia was associated with evidence of EMT before the development of significant tubulointerstitial fibrosis at 4 wk, as shown by decreased E-cadherin expression and an increased α-smooth muscle actin (α-SMA). Allopurinol significantly inhibited uric acid-induced changes in E-cadherin and α-SMA with an amelioration of renal fibrosis at 6 wk. In cultured NRK cells, uric acid induced EMT, which was blocked by the organic anion transport inhibitor probenecid. Uric acid increased expression of transcriptional factors associated with decreased synthesis of E-cadherin (Snail and Slug). Uric acid also increased the degradation of E-cadherin via ubiquitination, which is of importance since downregulation of E-cadherin is considered to be a triggering mechanism for EMT. In conclusion, uric acid induces EMT of renal tubular cells decreasing E-cadherin synthesis via an activation of Snail and Slug as well as increasing the degradation of E-cadherin.


Asunto(s)
Hiperuricemia/patología , Riñón/patología , Insuficiencia Renal Crónica/patología , Ácido Úrico/sangre , Actinas/metabolismo , Animales , Cadherinas/metabolismo , Creatinina/sangre , Modelos Animales de Enfermedad , Células Epiteliales/metabolismo , Células Epiteliales/patología , Hiperuricemia/metabolismo , Riñón/metabolismo , Masculino , Mesodermo/metabolismo , Mesodermo/patología , Ratas , Ratas Sprague-Dawley , Insuficiencia Renal Crónica/metabolismo , Vimentina/metabolismo
15.
Lab Invest ; 93(2): 194-206, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23207448

RESUMEN

The epithelial-to-mesenchymal transition (EMT) is known to have a role in appropriate embryonic development, the physiological response to injury and pathological events such as organ fibrosis and cancer progression. Glucocorticoid (GC), one of the most commonly used anti-inflammatory drugs, inhibits the deposition of extracellular matrix independent of its anti-inflammatory effect. The EMT of human peritoneal mesothelial cells (HPMCs) is a key mechanism of peritoneal fibrosis; however, it has not yet been investigated whether GC imposes any effect on the EMT of HPMCs. To investigate the therapeutic potential of GC on preserving peritoneal membrane function, we studied the effect of dexamethasone (DEXA), a synthetic GC, on the transforming growth factor-ß1 (TGF-ß1)-induced EMT in HPMCs. As assessed by changes in cell morphology, the expression of epithelial and mesenchymal cell markers (such as E-cadherin, ZO-1 and α-SMA, α-smooth muscle actin) and cell migration, DEXA inhibited the TGF-ß1-induced EMT. RU486, a glucocorticoid receptor (GR) antagonist, blocked the effect of DEXA on the TGF-ß1-induced EMT. Importantly, DEXA also induced the mesenchymal-to-epithelial transition of TGF-ß1-stimulated HPMCs. The beneficial effect of DEXA on the TGF-ß1-induced EMT was mediated through the amelioration of ERK and p38 mitogen-activated protein kinase (MAPK) phosphorylation; however, this effect was not related to the TGF-ß1-induced activation of Smad2/3 signaling. DEXA inhibited glycogen synthase kinase-3ß (GSK-3ß) phosphorylation and the Snail upregulation induced by TGF-ß1, which were also ameliorated by inhibitors of MAPK. In conclusion, this is the first study demonstrating the protective effect of DEXA on the EMT in TGF-ß1-stimulated HPMCs by inhibiting MAPK activation, GSK-3ß phosphorylation and Snail upregulation.


Asunto(s)
Dexametasona/farmacología , Células Epiteliales/fisiología , Transición Epitelial-Mesenquimal/efectos de los fármacos , Fibrosis Peritoneal/prevención & control , Peritoneo/citología , Factor de Crecimiento Transformador beta1/metabolismo , Actinas/metabolismo , Análisis de Varianza , Biomarcadores/metabolismo , Western Blotting , Cadherinas/metabolismo , Transición Epitelial-Mesenquimal/fisiología , Técnica del Anticuerpo Fluorescente , Regulación de la Expresión Génica/efectos de los fármacos , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Humanos , Mifepristona , Fosforilación/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Transcripción de la Familia Snail , Factores de Transcripción/metabolismo , Proteína de la Zonula Occludens-1/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
16.
Acta Haematol ; 129(4): 197-206, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23257958

RESUMEN

BACKGROUND AND AIMS: Immunomodulatory properties of mesenchymal stem cells (MSCs) have been applied to reduce the incidence of graft-versus-host disease (GVHD) after hematopoietic stem cell transplantation (HSCT). Among the various sources of MSCs that have immunomodulatory effects in vitro, only placenta-derived MSCs (PD-MSCs) have not been evaluated in an in vivo model of GVHD. In this study, we investigated the immunomodulatory properties of PD-MSCs in vitro and evaluated their clinical potential for controlling GVHD in an animal model. METHODS: A GVHD animal model was established by transplanting C57BL/6 donor bone marrow cells and spleen cells into lethally irradiated BALB/c recipient mice. To control GVHD, human PD-MSCs were transplanted into recipient mice (5 × 10(5) or 1 × 10(6) cells). RESULTS: PD-MSCs suppressed mitogen-stimulated T cell proliferation in vitro in a dose-dependent manner. Moreover, PD-MSCs inhibited cytokine secretion (interleukin-12, tumor necrosis factor-α and interferon-γ) of activated T cells. In vivo, the survival rate in the PD-MSC group (transplanted with 1 × 10(6) cells) was higher than that in the control group and histological scores were low in the PD-MSC group. CONCLUSION: We present the first evidence that human PD-MSCs can efficiently control GVHD in an HSCT in vivo model.


Asunto(s)
Enfermedad Injerto contra Huésped/inmunología , Enfermedad Injerto contra Huésped/prevención & control , Inmunomodulación , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/inmunología , Placenta/citología , Animales , Trasplante de Médula Ósea/inmunología , Diferenciación Celular , Modelos Animales de Enfermedad , Femenino , Fase G2 , Enfermedad Injerto contra Huésped/mortalidad , Enfermedad Injerto contra Huésped/patología , Humanos , Interferón gamma/metabolismo , Interleucina-12/metabolismo , Activación de Linfocitos/inmunología , Trasplante de Células Madre Mesenquimatosas , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Embarazo , Tasa de Supervivencia , Linfocitos T/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
17.
Sci Rep ; 13(1): 14074, 2023 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-37640754

RESUMEN

There has been an increasing demand for robotic coil positioning during repetitive transcranial magnetic stimulation (rTMS) treatment. Accurate coil positioning is crucial because rTMS generally targets specific brain regions for both research and clinical application with other reasons such as safety, consistency and reliability and individual variablity. Some previous studies have employed industrial robots or co-robots and showed they can more precisely stimulate the target cortical regions than traditional manual methods. In this study, we not only developed a custom-TMS robot for better TMS coil placement but also analyzed the therapeutic effects on depression. Treatment effects were evaluated by measuring regional cerebral blood flow (rCBF) using single-photon emission computed tomography and depression severity before and after rTMS for the two positioning methods. The rTMS preparation time with our robotic coil placement was reduced by 53% compared with that of the manual method. The position and orientation errors were also significantly reduced from 11.17 mm and 4.06° to 0.94 mm and 0.11°, respectively, confirming the superiority of robotic positioning. The results from clinical and neuroimaging assessments indicated comparable improvements in depression severity and rCBF in the left dorsolateral prefrontal cortex between the robotic and manual rTMS groups. A questionnaire was used to determine the patients' feelings about the robotic system, including the safety and preparation time. A high safety score indicated good acceptability of robotic rTMS at the clinical site.


Asunto(s)
Procedimientos Quirúrgicos Robotizados , Robótica , Humanos , Estimulación Magnética Transcraneal , Proyectos Piloto , Depresión/terapia , Reproducibilidad de los Resultados
18.
Med Eng Phys ; 118: 104023, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37536829

RESUMEN

BACKGROUND: Ultrasonic neuromodulation (UNMOD) provides a non-invasive brain stimulation. However, the high-resolution region-specificity of UNMOD with a single element transducer combined with a mechanical positioning system could have limits due to the intrinsic positioning error from mechanical systems. OBJECTIVE/HYPOTHESIS: A phased array system could lead to highly selective neuromodulation with electronic control. METHODS: A specialized phased-array system with a robotic arm is implemented for a rhesus monkey model. Various primary motor cortex areas related to tail, hand, and mouth were stimulated with a 200 µm step size. The ultrasonic parameters were ISPTA of 840 mW/cm2, pulse repetition frequency of 100 Hz, and a 5% duty factor at 600 kHz. The induced movement were recorded and analyzed. RESULTS: Separate digits, mouth, and tongue motions were successfully induced by electronically controlling the focus. The identical body part movement could be induced when the focus was moved back to the identical primary motor cortex with electronic control. Accordingly, the reproducibility of UNMOD could be partially validated with rhesus monkey model. CONCLUSION: A phased-array system appears to have a potential for the non-invasive and region-selective neuromodulation method.


Asunto(s)
Procedimientos Quirúrgicos Robotizados , Reproducibilidad de los Resultados , Ultrasonografía , Transductores , Neurotransmisores
19.
J Comp Neurol ; 529(7): 1308-1326, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32869318

RESUMEN

Chronic traumatic encephalopathy (CTE) is a neurodegenerative disorder that is associated with repetitive head impacts. Neuropathologically, it is defined by the presence of perivascular hyperphosphorylated tau aggregates in cortical tissue (McKee et al., 2016, Acta Neuropathologica, 131, 75-86). Although many pathological and assumed clinical correlates of CTE have been well characterized, its effects on cortical dendritic arbors are still unknown. Here, we quantified dendrites and dendritic spines of supragranular pyramidal neurons in tissue from human frontal and occipital lobes, in 11 cases with (Mage = 79 ± 7 years) and 5 cases without (Mage = 76 ± 11 years) CTE. Tissue was stained with a modified rapid Golgi technique. Dendritic systems of 20 neurons per region in each brain (N = 640 neurons) were quantified using computer-assisted morphometry. One key finding was that CTE neurons exhibited increased variability and distributional changes across six of the eight dendritic system measures, presumably due to ongoing degeneration and compensatory reorganization of dendritic systems. However, despite heightened variation among CTE neurons, CTE cases exhibited lower mean values than Control cases in seven of the eight dendritic system measures. These dendritic alterations may represent a new pathological marker of CTE, and further examination of dendritic changes could contribute to both mechanistic and functional understandings of the disease.


Asunto(s)
Encefalopatía Traumática Crónica/patología , Dendritas/patología , Anciano , Anciano de 80 o más Años , Humanos , Masculino
20.
Radiother Oncol ; 138: 9-16, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31136962

RESUMEN

OBJECTIVE: Hepatocyte growth factor (HGF) and its receptor MET are expressed in the salivary glands during developmental stages and tumor formation; however, the function of HGF in injured salivary gland tissues remains unclear. The present study investigated the role of HGF in protecting the salivary glands against radiation-induced injury using an organotypic culture method. MATERIALS AND METHODS: Acinar-like organoids were formed by means of a three-dimensional (3D) human parotid tissue-derived spheroids (hPTS) culture method. Radioprotective effects of HGF on irradiated hPTS and signaling pathways on radioprotection were investigated. RESULTS: We detected MET expression in hPTS grown in a 3D culture. Treatment of irradiated hPTS with recombinant human HGF (rhHGF) restored salivary marker expression and secretory function of hPTS. Changes in the phosphorylation levels of apoptosis-related proteins through HGF-MET axis inhibited radiation-induced apoptosis. Treatment with PHA665752, a MET inhibitor, blocked MET-PI3K-AKT pathway, increased apoptosis, and suppressed the radioprotective effect of rhHGF against IR-induced damage of hPTS. CONCLUSIONS: These results suggest that HGF is a key effector of radioprotection and that HGF-MET-PI3K-AKT axis is involved in protecting the salivary glands from radiation-induced apoptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Factor de Crecimiento de Hepatocito/farmacología , Proteínas Proto-Oncogénicas c-met/fisiología , Traumatismos por Radiación/prevención & control , Glándulas Salivales/efectos de la radiación , Humanos , Indoles/farmacología , Sulfonas/farmacología
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