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1.
Dis Colon Rectum ; 65(2): e80-e84, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34840298

RESUMEN

BACKGROUND: Curvilinear array ultrasound transducers enable tissue sampling and have therapeutic capabilities. Nevertheless, colonic intubation and maneuvering with these transducers is technically challenging and is therefore typically limited to the rectosigmoid area. This retrospective cohort study aimed to evaluate the safety, feasibility, and diagnostic yield of colonoscopic ultrasound-guided fine-needle aspiration in deep colonic intubation. IMPACT OF INNOVATION: The impact of this innovation is to enable tissue sampling of colonic and extracolonic lesions guided by endoscopic ultrasound. TECHNOLOGY, MATERIALS, AND METHODS: Curvilinear array ultrasound is used in the evaluation of luminal and extraluminal colonic diseases. Thirteen patients underwent colonoscopic ultrasound with a curvilinear array ultrasound endoscope in a single center for subepithelial lesions, cancer staging, and extracolonic lesions from July 2015 to February 2021. Endosonography was performed using an Olympus EU-ME1 and GF-UCT 180 with a 5-12MHz curvilinear array transducer. The primary outcome was the percentage of patients who were successfully scanned with the endoscopic ultrasound. The secondary outcomes included the success rate of fine-needle aspiration, the diagnostic yield of the tissue samples, and the adverse events related to the procedure. PRELIMINARY RESULTS: A total of 13 female patients underwent colonoscopic ultrasound. All patients (100%, 13/13) were successfully scanned. Fine-needle aspiration was deemed necessary and successfully performed in 100% (5/5) of the patients. Tissue samples collected by fine-needle aspiration resulted in a diagnostic yield of 60%, and no adverse events resulted from this intervention. CONCLUSIONS: This study demonstrates the feasibility of performing colonoscopic ultrasound with a curvilinear array transducer. Fine-needle aspiration for subepithelial, colonic, and extracolonic lesions is feasible and safe in this setting with no adverse events reported in our study. FUTURE DIRECTIONS: Future research should be directed toward validating colonoscopic ultrasound with a curvilinear array transducer technique in prospective randomized trials. Studies evaluating the feasibility and safety of endoscopic ultrasound-guided interventions in the colon, such as abscess drainage and enteral anastomosis, should be considered.


Asunto(s)
Enfermedades del Colon/patología , Colonoscopía/instrumentación , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/instrumentación , Endosonografía/instrumentación , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades del Colon/diagnóstico por imagen , Colonoscopía/efectos adversos , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/efectos adversos , Endosonografía/efectos adversos , Estudios de Factibilidad , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos
2.
J Cell Physiol ; 235(2): 1723-1732, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31301074

RESUMEN

Intracellular Ca2+ signals are essential for stem cell function and play a significant role in the differentiation process. Dental pulp stem cells (DPSCs) are a potential source of stem cells; however, the mechanisms controlling cell differentiation remain largely unknown. Utilizing rat DPSCs, we examined the effect of adenosine triphosphate (ATP) on osteoblast differentiation and characterized its mechanism of action using real-time Ca 2+ imaging analysis. Our results revealed that ATP enhanced osteogenesis as indicated by Ca 2+ deposition in the extracellular matrix via Alizarin Red S staining. This was consistent with upregulation of osteoblast genes BMP2, Mmp13, Col3a1, Ctsk, Flt1, and Bgn. Stimulation of DPSCs with ATP (1-300 µM) increased intracellular Ca 2+ signals in a concentration-dependent manner, whereas histamine, acetylcholine, arginine vasopressin, carbachol, and stromal-cell-derived factor-1α failed to do so. Depletion of intracellular Ca 2+ stores in the endoplasmic reticulum by thapsigargin abolished the ATP responses which, nevertheless, remained detectable under extracellular Ca 2+ free condition. Furthermore, the phospholipase C (PLC) inhibitor U73122 and the inositol triphosphate (IP 3 ) receptor inhibitor 2-aminoethoxydiphenyl borate inhibited the Ca 2+ signals. Our findings provide a better understanding of how ATP controls osteogenesis in DPSCs, which involves a Ca 2+ -dependent mechanism via the PLC-IP 3 pathway. This knowledge could help improve osteogenic differentiation protocols for tissue regeneration of bone structures.


Asunto(s)
Adenosina Trifosfato/farmacología , Señalización del Calcio/fisiología , Pulpa Dental/metabolismo , Células Madre Mesenquimatosas/metabolismo , Osteoblastos/metabolismo , Animales , Señalización del Calcio/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Pulpa Dental/citología , Pulpa Dental/efectos de los fármacos , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Osteoblastos/efectos de los fármacos , Osteogénesis/genética , Osteogénesis/fisiología , Ratas , Ratas Sprague-Dawley , Fosfolipasas de Tipo C/metabolismo
3.
Biol Reprod ; 99(6): 1159-1170, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-29982498

RESUMEN

Mechanisms regulating sperm motility activation are generally known in oviparous fishes, but are poorly understood in viviparous species. The mechanism of osmotic-shock induced signaling for oviparous fishes is not suitable for viviparous fishes which activate sperm motility within an isotonic environment. In addition, the presence of sperm bundles in viviparous fishes further complicates study of sperm activation mechanisms. The goal of this study was to establish methodologies to detect intracellular Ca2+ signals from sperm cells within bundles, and to investigate the signaling mechanism of sperm activation of viviparous fish using Redtail Splitfin (Xenotoca eiseni) as a model. Motility was assessed by classification of bundle dissociation and computer-assisted sperm analysis, and intracellular Ca2+ was assessed using the fluorescent probe Fura-2 AM. Bundle dissociation and sperm motility increased with extracellular Ca2+ and pH levels. Intracellular Ca2+ signals were detected from sperm within bundles, and increased significantly with extracellular Ca2+ and pH levels. Major channel blockers known to inhibit Ca2+ influx (NiCl2, ruthenium red, GdCl3, SKF-96365, nimodipine, verapamil, methoxyverapamil, mibefradil, NNC 55-0396, ω-Conotoxin MVIIC, bepridil, and 2-APB) failed to inhibit Ca2+ influx, except for CdCl2, which partially inhibited the influx. We propose a novel mechanism for motility regulation of fish sperm: an alkaline environment in the female reproductive tract opens Ca2+ channels in the sperm plasma membrane without osmotic shock, and the Ca2+ influx functions as a second messenger to activate motor proteins controlling flagella movement.


Asunto(s)
Calcio/metabolismo , Peces/fisiología , Motilidad Espermática/efectos de los fármacos , Viviparidad de Animales no Mamíferos/fisiología , Animales , Bloqueadores de los Canales de Calcio/farmacología , Cloruro de Calcio/farmacología , Señalización del Calcio/efectos de los fármacos , Señalización del Calcio/fisiología , Femenino , Concentración de Iones de Hidrógeno , Masculino , Espermatozoides/fisiología
4.
Am J Physiol Endocrinol Metab ; 311(2): E530-41, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27436609

RESUMEN

To better understand the role of irisin in humans, we examined the effects of irisin in human primary adipocytes and fresh human subcutaneous white adipose tissue (scWAT). Human primary adipocytes derived from 28 female donors' fresh scWAT were used to examine the effects of irisin on browning and mitochondrial respiration, and preadipocytes were used to examine the effects of irisin on adipogenesis and osteogenesis. Cultured fragments of scWAT and perirenal brown fat were used for investigating signal transduction pathways that mediate irisin's browning effect by Western blotting to detect phosphorylated forms of p38, ERK, and STAT3 as well as uncoupling protein 1 (UCP1). Individual responses to irisin in scWAT were correlated with basal expression levels of brown/beige genes. Irisin upregulated the expression of browning-associated genes and UCP1 protein in both cultured primary mature adipocytes and fresh adipose tissues. It also significantly increased thermogenesis at 5 nmol/l by elevating cellular energy metabolism (OCR and ECAR). Treating human scWAT with irisin increased UCP1 expression by activating the ERK and p38 MAPK signaling. Blocking either pathway with specific inhibitors abolished irisin-induced UCP1 upregulation. However, our results showed that UCP1 in human perirenal adipose tissue was insensitive to irisin. Basal levels of brown/beige and FNDC5 genes correlated positively with the browning response of scWAT to irisin. In addition, irisin significantly inhibited adipogenic differentiation but promoted osteogenic differentiation. We conclude that irisin promotes "browning" of mature white adipocytes by increasing cellular thermogenesis, whereas it inhibits adipogenesis and promotes osteogenesis during lineage-specific differentiation. Our findings provide a rationale for further exploring the therapeutic use of irisin in obesity and exercise-associated bone formation.


Asunto(s)
Adipocitos Blancos/efectos de los fármacos , Adipogénesis/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Fibronectinas/farmacología , Mitocondrias/efectos de los fármacos , Osteogénesis/efectos de los fármacos , ARN Mensajero/efectos de los fármacos , Termogénesis/efectos de los fármacos , Adipocitos Marrones/efectos de los fármacos , Adipocitos Marrones/metabolismo , Adipocitos Blancos/metabolismo , Adipogénesis/genética , Adolescente , Adulto , Anciano , Western Blotting , Respiración de la Célula/efectos de los fármacos , Células Cultivadas , Ejercicio Físico , Quinasas MAP Reguladas por Señal Extracelular/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Mitocondrias/metabolismo , Obesidad/metabolismo , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteogénesis/genética , Fosfoproteínas/efectos de los fármacos , Fosfoproteínas/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Factor de Transcripción STAT3/efectos de los fármacos , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Grasa Subcutánea/citología , Termogénesis/genética , Proteína Desacopladora 1/efectos de los fármacos , Proteína Desacopladora 1/metabolismo , Regulación hacia Arriba , Adulto Joven , Proteínas Quinasas p38 Activadas por Mitógenos/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
5.
J Cell Sci ; 126(Pt 16): 3638-48, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23750005

RESUMEN

Induced pluripotent stem cells (iPSCs) hold great promise for cell therapy. However, their low efficiency of lineage-specific differentiation and tumorigenesis severely hinder clinical translation. We hypothesized that reprogramming of somatic cells into lineage-specific progenitor cells might allow for large-scale expansion, avoiding the tumorigenesis inherent with iPSCs and simultaneously facilitating lineage-specific differentiation. Here we aimed at reprogramming rat hepatic WB cells, using four Yamanaka factors, into pancreatic progenitor cells (PPCs) or intermediate (IM) cells that have characteristics of PPCs. IM clones were selected based on their specific morphology and alkaline phosphatase activity and stably passaged under defined culture conditions. IM cells did not have iPSC properties, could be stably expanded in large quantity, and expressed all 14 genes that are used to define the PPC developmental stage. Directed differentiation of IM and WB cells by Pdx1-Ngn3-MafA (PNM) into pancreatic beta-like cells revealed that the IM cells are more susceptible to directed beta cell differentiation because of their open chromatin configuration, as demonstrated by expression of key pancreatic beta cell genes, secretion of insulin in response to glucose stimulation, and easy access to exogenous PNM proteins at the rat insulin 1 and Pdx1 promoters. This notion that IM cells are superior to their parental cells is further supported by the epigenetic demonstration of accessibility of Pdx1 and insulin 1 promoters. In conclusion, we have developed a strategy to derive and expand PPC cells from hepatic WB cells using conventional cell reprogramming. This proof-of-principal study may offer a novel, safe and effective way to generate autologous pancreatic beta cells for cell therapy of diabetes.


Asunto(s)
Hepatocitos/citología , Células Secretoras de Insulina/citología , Animales , Diferenciación Celular/fisiología , Línea Celular Tumoral , Células Cultivadas , Metilación de ADN , Hepatocitos/metabolismo , Proteínas de Homeodominio/genética , Humanos , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Ratones , Ratones Endogámicos NOD , Ratones SCID , Regiones Promotoras Genéticas , Ratas , Células Madre/citología , Células Madre/metabolismo , Transactivadores/genética
6.
Biochem J ; 463(1): 123-34, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25001294

RESUMEN

Intracellular Ca2+ oscillations are frequently observed during stem cell differentiation, and there is evidence that it may control adipogenesis. The transient receptor potential melastatin 4 channel (TRPM4) is a key regulator of Ca2+ signals in excitable and non-excitable cells. However, its role in human adipose-derived stem cells (hASCs), in particular during adipogenesis, is unknown. We have investigated TRPM4 in hASCs and examined its impact on histamine-induced Ca2+ signalling and adipogenesis. Using reverse transcription (RT)-PCR, we have identified TRPM4 gene expression in hASCs and human adipose tissue. Electrophysiological recordings revealed currents with the characteristics of those reported for the channel. Furthermore, molecular suppression of TRPM4 with shRNA diminished the Ca2+ signals generated by histamine stimulation, mainly via histamine receptor 1 (H1) receptors. The increases in intracellular Ca2+ were due to influx via voltage-dependent Ca2+ channels (VDCCs) of the L-type (Ca(v)1.2) and release from the endoplasmic reticulum. Inhibition of TRPM4 by shRNA inhibited adipogenesis as indicated by the reduction in lipid droplet accumulation and adipocyte gene expression. These results suggest that TRPM4 is an important regulator of Ca2+ signals generated by histamine in hASCs and is required for adipogenesis.


Asunto(s)
Adipogénesis/fisiología , Tejido Adiposo/metabolismo , Señalización del Calcio/fisiología , Histamina/metabolismo , Células Madre/metabolismo , Canales Catiónicos TRPM/biosíntesis , Tejido Adiposo/citología , Adulto , Canales de Calcio Tipo L/genética , Canales de Calcio Tipo L/metabolismo , Células Cultivadas , Regulación de la Expresión Génica/fisiología , Histamina/genética , Humanos , Masculino , Persona de Mediana Edad , Receptores Histamínicos H1/genética , Receptores Histamínicos H1/metabolismo , Células Madre/citología , Canales Catiónicos TRPM/genética
7.
Stem Cells ; 31(1): 167-77, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23081848

RESUMEN

Elevations in the intracellular Ca(2+) concentration are a phenomena commonly observed during stem cell differentiation but cease after the process is complete. The transient receptor potential melastatin 4 (TRPM4) is an ion channel that controls Ca(2+) signals in excitable and nonexcitable cells. However, its role in stem cells remains unknown. The aim of this study was to characterize TRPM4 in rat dental follicle stem cells (DFSCs) and to determine its impact on Ca(2+) signaling and the differentiation process. We identified TRPM4 gene expression in DFSCs, but not TRPM5, a closely related channel with similar function. Perfusion of cells with increasing buffered Ca(2+) resulted in a concentration-dependent activation of currents typical for TRPM4, which were also voltage-dependent and had Na(+) conductivity. Molecular suppression with shRNA decreased channel activity and cell proliferation during osteogenesis but not adipogenesis. As a result, enhanced mineralization and phosphatase enzyme activity were observed during osteoblast formation, although DFSCs failed to differentiate into adipocytes. Furthermore, the normal agonist-induced first and secondary phases of Ca(2+) signals were transformed into a gradual and sustained increase which confirmed the channels' ability to control Ca(2+) signaling. Using whole genome microarray analysis, we identified several genes impacted by TRPM4 during DFSC differentiation. These findings suggest an inhibitory role for TRPM4 on osteogenesis while it appears to be required for adipogenesis. The data also provide a potential link between the Ca(2+) signaling pattern and gene expression during stem cell differentiation.


Asunto(s)
Canales de Calcio/metabolismo , Saco Dental/metabolismo , Células Madre/metabolismo , Canales Catiónicos TRPM/metabolismo , Adipogénesis/fisiología , Animales , Calcio/metabolismo , Señalización del Calcio , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Potenciales de la Membrana , Osteogénesis/fisiología , Técnicas de Placa-Clamp , Interferencia de ARN , ARN Interferente Pequeño , Ratas , Ratas Sprague-Dawley , Canales Catiónicos TRPM/genética , Diente/metabolismo
8.
Fish Shellfish Immunol ; 34(3): 756-61, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23261510

RESUMEN

The aim of this study was to determine the efficacy of dietary administration of Lactobacillus pentosus PL11 on growth performance and the immune and antioxidant systems in Japanese eel Anguilla japonica challenged with Edwardsiella tarda. A total of 75 Japanese eels (24.63±0.83 g) were grouped into 5 treatment diets which were a control diet (C) without E. tarda and 4 treatment diets with E. tarda challenge, including C for E. tarda challenge (NC), C plus L. pentosus PL11 supplemented diet (108 cfu g⁻¹) (T-PL11), C plus L. pentosus KCCM 40997 supplemented diet (108 cfu g⁻¹) (T-Lp) and C plus Weissella hellenica DS-12 supplemented diet (108 cfu g⁻¹) (T-Wh) for 5 weeks (4 week before and 1 week after challenge). The results showed enhanced growth performance in fish fed the diet containing L. pentosus PL11 compared to others. The growth performance parameters including specific growth rate (SGR) and weight gain (WG), feed intake (FI), feed conversion ratio (FCR) and survival were significantly (P<0.05) higher in fish maintained on L. pentosus PL11 supplemented diet compared to C and NC. T-PL11 group also shows a significant increase in the levels of plasma immunoglobulin M, CAT and SOD activities compared to NC. Hematological parameters and mieloperoxidase were significantly better in fish fed the L. pentosus PL11 supplemented diet than in the control. L. pentosus PL11 supplementation recover the reduced expression of SOD, CAT and heat shock protein 70 genes in liver and intestine in pathogen challenged fishes. In conclusion the result of the current study demonstrated L. pentosus PL11 potential as an alternative to antibiotic supplementation to improve the growth and health performance of Japanese eel (A. japonica).


Asunto(s)
Anguilla/crecimiento & desarrollo , Anguilla/inmunología , Infecciones por Enterobacteriaceae/veterinaria , Enfermedades de los Peces/inmunología , Inmunidad Innata , Lactobacillus/metabolismo , Anguilla/microbiología , Animales , Antioxidantes/metabolismo , Dieta/veterinaria , Edwardsiella tarda/fisiología , Infecciones por Enterobacteriaceae/inmunología , Infecciones por Enterobacteriaceae/microbiología , Enfermedades de los Peces/microbiología , Lactobacillus/aislamiento & purificación , Probióticos/administración & dosificación
9.
Differentiation ; 83(5): 233-41, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22466603

RESUMEN

Embryonic stem (ES) cells are pluripotent cells that can differentiate into all three main germ layers: endoderm, mesoderm, and ectoderm. Although a number of methods have been developed to differentiate ES cells into neuronal phenotypes such as sensory and motor neurons, the efficient generation of GABAergic interneurons from ES cells still presents an ongoing challenge. Because the main output of inhibitory GABAergic interneurons is the gamma-aminobutyric-acid (GABA), a neurotransmitter whose controlled homeostasis is required for normal brain function, the efficient generation in culture of functional interneurons may have future implications on the treatment of neurological disorders such as epilepsy, autism, and schizophrenia. The goal of this work was to examine the generation of GABAergic neurons from mouse ES cells by comparing an embryoid body-based methodology versus a hydrogel-based encapsulation protocol that involves the use of all-trans-retinoid acid (RA). We observed that (1) there was a 2-fold increase in neuronal differentiation in encapsulated versus non-encapsulated cells and (2) there was an increase in the specificity for interneuronal differentiation in encapsulated cells, as assessed by mRNA expression and electrophysiology approaches. Furthermore, our results indicate that most of the neurons obtained from encapsulated mouse ES cells are GABA-positive (∼87%). Thus, these results suggest that combining encapsulation of ES cells and RA treatment provide a more efficient and scalable differentiation strategy for the generation in culture of functional GABAergic interneurons. This technology may have implications for future cell replacement therapies and the treatment of CNS disorders.


Asunto(s)
Diferenciación Celular , Tratamiento Basado en Trasplante de Células y Tejidos , Células Madre Embrionarias/citología , Neuronas GABAérgicas/citología , Tretinoina/farmacología , Animales , Encéfalo/crecimiento & desarrollo , Encéfalo/metabolismo , Diferenciación Celular/efectos de los fármacos , Línea Celular , Cuerpos Embrioides/citología , Cuerpos Embrioides/metabolismo , Células Madre Embrionarias/trasplante , Neuronas GABAérgicas/metabolismo , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Factor Inhibidor de Leucemia/metabolismo , Ratones , Canales de Potasio/metabolismo , Ácido gamma-Aminobutírico/metabolismo
10.
Molecules ; 18(11): 13886-903, 2013 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-24284487

RESUMEN

Three dietary monosaccharides, (glucose, fructose, and ribose), have different rates of protein glycation that accelerates the production of advanced glycation end-products (AGEs). The present work was conducted to investigate the effect of ferulic acid (FA) on the three monosaccharide-mediated protein glycations and oxidation of BSA. Comparing the percentage reduction, FA (1-5 mM) reduced the level of fluorescence AGEs (F-AGEs) and N(ε)-(carboxymethyl) lysine (N(ε)-CML) in glucose-glycated BSA (F-AGEs = 12.61%-36.49%; N(ε)-CML = 33.61%-66.51%), fructose-glycated BSA (F-AGEs = 25.28%-56.42%; N(ε)-CML = 40.21%-62.91%), and ribose-glycated BSA (F-AGEs = 25.63%-51.18%; N(ε)-CML = 26.64%-64.08%). In addition, the percentages of FA reduction of fructosamine (Frc) and amyloid cross ß-structure (Amy) were Frc = 20.45%-43.81%; Amy = 17.84%-34.54% in glucose-glycated BSA, Frc = 25.17%-36.92%; Amy = 27.25%-39.51% in fructose-glycated BSA, and Frc = 17.34%-29.71%; Amy = 8.26%-59.92% in ribose-glycated BSA. FA also induced a reduction in protein carbonyl content (PC) and loss of protein thiol groups (TO) in glucose-glycated BSA (PC = 37.78%-56.03%; TO = 6.75%-13.41%), fructose-glycated BSA (PC = 36.72%-52.74%; TO = 6.18%-20.08%), and ribose-glycated BSA (PC = 25.58%-33.46%; TO = 20.50%-39.07%). Interestingly, the decrease in fluorescence AGEs by FA correlated with the level of N(ε)-CML, fructosamine, amyloid cross ß-structure, and protein carbonyl content. Therefore, FA could potentially be used to inhibit protein glycation and oxidative damage caused by monosaccharides, suggesting that it might prevent AGEs-mediated pathologies during diabetic complications.


Asunto(s)
Ácidos Cumáricos/química , Monosacáridos/química , Albúmina Sérica Bovina/química , Animales , Bovinos , Productos Finales de Glicación Avanzada/química , Glicosilación , Oxidación-Reducción
11.
Biomed Pharmacother ; 162: 114677, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37044024

RESUMEN

Cyanidin is the most abundant anthocyanin found in red-purple plants and possesses anti-obesity properties. However, its mechanism of action in adipocytes remains unknown. The objective of this study was to elucidate how cyanidin inhibits adipocyte formation in 3T3-L1 preadipocytes. Cells were cultured in adipogenic differentiation medium supplemented with cyanidin and examined for adipogenesis, cell viability, and adipocyte gene expression using Oil Red O staining, MTT assay, and RT-qPCR. Real-time Ca2+ imaging analysis was performed in living cells to elucidate cyanidin's mechanism of action. The results demonstrated that cyanidin (1-50 µM) supplementation to the adipogenic medium inhibited adipogenesis by downregulating adipogenic marker gene expression (PPARγ, C/EBPα, adiponectin, and aP2) without affecting cell viability after 4 days of treatment. Stimulation of cells with cyanidin (30-100 µM) increased intracellular Ca2+ in a concentration dependent manner with peak calcium increases at 50 µM. Pretreatment of cells with the phospholipase C (PLC) inhibitor U73122, inositol triphosphate (IP3) receptor blocker 2-APB, and depletion of endoplasmic reticulum Ca2+ stores by thapsigargin abolished the Ca2+ increases by cyanidin. These findings suggested that cyanidin inhibits adipocyte formation by activating the PLC-IP3 pathway and intracellular Ca2+ signaling. Our study is the first report describing the mechanism underlying the anti-obesity effect of cyanidin.


Asunto(s)
Adipogénesis , Antocianinas , Ratones , Animales , Antocianinas/farmacología , Células 3T3-L1 , Fosfolipasas de Tipo C/metabolismo , Regulación hacia Abajo , Diferenciación Celular , Obesidad/metabolismo , PPAR gamma/metabolismo
12.
Int J Biol Macromol ; 223(Pt A): 1578-1585, 2022 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-36375667

RESUMEN

Insulin fibril formation decreases the effectiveness of insulin therapy and causes amyloidosis in diabetes. Studies suggest that phytochemicals are capable of inhibiting fibril formation. Herein, we investigated the inhibitory effects of anthocyanins, including cyanidin, cyanidin-3-glucoside (C3G), cyanidin-3-rutinoside (C3R), malvidin, and malvidin-3-glucoside (M3G) on fibril formation. Our results revealed that anthocyanins (50-200 µM) significantly reduced the formation of insulin fibrils by increasing lag times and decreasing ThT fluorescence at the plateau phase. These findings were confirmed by TEM images, which showed reduced fibril length and number. Furthermore, FTIR analysis indicated that anthocyanins reduced the secondary structure transition of insulin from α-helix to ß-sheet. Anthocyanins interacted with monomeric insulin (residues B8-B30) via H-bonds, van der Waals, and hydrophobic interactions, covering the fibril-prone segments of insulin (residues B12-B17). Based on the structure-activity analysis, the presence of glycosides and hydroxyl groups on phenyl rings increased intermolecular interaction, mediating the inhibitory effect of anthocyanins on fibril formation in the order of malvidin < cyanidin < M3G < C3G < C3R. Moreover, anthocyanins formed H-bonds with preformed insulin fibrils, except for malvidin. In preadipocytes, C3R, C3G, and cyanidin attenuated insulin fibril-induced cytotoxicity. In conclusion, anthocyanins are effective inhibitors of insulin fibril formation and cytotoxicity.


Asunto(s)
Antocianinas , Insulina , Animales , Ratones , Antocianinas/farmacología , Antocianinas/química , Células 3T3-L1 , Glicósidos , Estructura Secundaria de Proteína
13.
Biomed Pharmacother ; 146: 112494, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34891116

RESUMEN

Cyanidin-3-rutinoside (C3R) is an anthocyanin with anti-diabetic properties found in red-purple fruits. However, the molecular mechanisms of C3R on Ca2+-dependent insulin secretion remains unknown. This study aimed to identify C3R's mechanisms of action in pancreatic ß-cells. Rat INS-1 cells were used to elucidate the effects of C3R on insulin secretion, intracellular Ca2+ signaling, and gene expression. The results showed that C3R at 60, 100, and 300 µM concentrations significantly increased insulin secretion via intracellular Ca2+ signaling. The exposure of cells with C3R concentrations up to 100 µM did not affect cell viability. Pretreatment of cells with nimodipine (voltage-dependent Ca2+ channel (VDCC) blocker), U73122 (PLC inhibitor), and 2-APB (IP3 receptor blocker) inhibited the intracellular Ca2+ signals by C3R. Interestingly, C3R increased intracellular Ca2+ signals and insulin secretion after depletion of endoplasmic reticulum Ca2+ stores by thapsigargin. However, insulin secretion was abolished under extracellular Ca2+-free conditions. Moreover, C3R upregulated mRNA expression for Glut2 and Kir6.2 genes. These findings indicate that C3R stimulated insulin secretion by promoting Ca2+ influx via VDCCs and activating the PLC-IP3 pathway. C3R also upregulates the expression of genes necessary for glucose-induced insulin secretion. This is the first study describing the molecular mechanisms by which C3R stimulates Ca2+-dependent insulin secretion from pancreatic ß-cells. These findings contribute to our understanding on how anthocyanins improve hyperglycemia in diabetic patients.


Asunto(s)
Antocianinas/farmacología , Secreción de Insulina/efectos de los fármacos , Células Secretoras de Insulina/efectos de los fármacos , Animales , Calcio/metabolismo , Canales de Calcio Tipo L/genética , Línea Celular , Supervivencia Celular/efectos de los fármacos , Transportador de Glucosa de Tipo 2/genética , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Células Secretoras de Insulina/metabolismo , Canales de Potasio de Rectificación Interna/genética , Ratas , Fosfolipasas de Tipo C/metabolismo
14.
Food Funct ; 13(9): 5166-5176, 2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35421887

RESUMEN

Berry fruits are rich in polyphenolic compounds (PCs) and may promote health benefits. Anthocyanin (ACN) concentrations of red raspberry (RR) (Rubus idaeus) extracts were 887.6 ± 262.8 µg g-1, consisting mainly of cyanidin-3-sophoroside (C3S) equivalents. To test the efficacy of RR in diabetes treatment, seven patients with type 2 diabetes mellitus (T2DM) were given one oral RR serving (123 g per day) for two weeks. Blood samples were drawn at the baseline (BSL) and post-feeding (PF) periods for phenolic metabolite, inflammation and insulin resistance (IR) biomarker analysis. Two urolithin conjugates, urolithin A glucuronide (Uro-A glur) and urolithin A sulphate (Uro-A sulf) were identified in the PF period in 5 of the 7 patients in nanomolar concentrations (1.6 ± 0.7-63.2 ± 31.2 nM). ACN-derived metabolites such as protocatechuic acid (PCA) and 3,4-dihydroxyphenylacetic acid (DOPAC) were at micromolar levels and were higher during the PF period for diabetics and the levels were as follows: BSL: PCA = 0.6 ± 0.4, DOPAC = 1.2 ± 0.5; PF: PCA = 0.6 ± 0.4, DOPAC = 1.1 ± 0.6. The results revealed significant reductions in high sensitivity C-reactive protein, hsCRP (p = 0.01) and there was a downward trend in IR measured by the homeostatic model assessment of insulin resistance (HOMA-IR, p = 0.0584) in T2DM patients. DOPAC (1-100 µM) failed to stimulate insulin secretion in pancreatic ß-cells. The multiplex assay showed variations in the cytokine levels between patients, but differences were not significant. This study demonstrates a potential use of RR in the treatment of inflammation and possibly IR as well in patients with type 2 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Rubus , Ácido 3,4-Dihidroxifenilacético , Biomarcadores , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Promoción de la Salud , Humanos , Inflamación/tratamiento farmacológico , Insulina , Proyectos Piloto , Polifenoles/farmacología
15.
Microb Pathog ; 51(4): 297-303, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21477644

RESUMEN

In a previous study, we demonstrated pneumococcal EstA-induced inflammatory response through NF-κB and MAPK-dependent pathways. Herein, we tested the hypothesis that the Janus kinase 2 (JAK2) activation and associated signaling cascades may also be involved in EstA-induced inflammatory process in RAW 264.7 macrophages. Our immunoblot analysis indicated EstA-induced activation of JAK2, with the phosphorylated protein detected from 1 to 24 h post-stimulation. As type I interferon (IFN) signaling requires the JAK/STAT pathway, we investigated EstA-induced expression of INF-α4 and INF-ß by semi-quantitative and quantitative RT PCR. Our results indicated both concentration- and time-dependent increases in both IFN-α4 and IFN-ß mRNA expression after EstA challenge, with the highest fold-increases observed at 4 h and 6 h post-stimulation for IFN-α4 and IFN-ß mRNA, respectively. Furthermore, we applied a pharmacological approach to demonstrate the effect of JAK2 inhibition on EstA-induced nitric oxide (NO) and pro-inflammatory cytokine production. The JAK2 inhibitor AG-490 reduced significantly (P < 0.05) EstA-induced NO production and the expression of iNOS mRNA in a concentration-dependent manner. Similarly, EstA-induced IL-1ß and IL-6 production and their respective mRNA expression were markedly suppressed by AG-490. However, AG-490 had no inhibitory effect on both mRNA and protein levels of TNF-α. Taken together, we demonstrate that JAK2 activation and IFN I signaling are integral parts of EstA-induced inflammatory process. Further studies will elucidate the interaction of the different signaling pathways, the specific downstream targets of JAK2, the kinetics of cytokine release, and if EstA could induce the pro-inflammatory mediators to the same extent in alveolar macrophages.


Asunto(s)
Proteínas Bacterianas/toxicidad , Hidrolasas de Éster Carboxílico/toxicidad , Citocinas/biosíntesis , Janus Quinasa 2/metabolismo , Macrófagos/inmunología , Macrófagos/microbiología , Streptococcus pneumoniae/patogenicidad , Animales , Western Blotting , Línea Celular , Perfilación de la Expresión Génica , Ratones , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Factores de Tiempo
16.
Nutrients ; 12(5)2020 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-32384625

RESUMEN

Recently, the mechanisms responsible for anti-glycation activity of cyanidin and its derivatives on the inhibition of methylglyoxal (MG)-induced protein glycation and advanced glycation-end products (AGEs) as well as oxidative DNA damage were reported. In this study, we investigated the protective effect of cyanidin against MG-induced oxidative stress and apoptosis in rat INS-1 pancreatic ß-cells. Exposure of cells to cytotoxic levels of MG (500 µM) for 12 h caused a significant reduction in cell viability. However, the pretreatment of cells with cyanidin alone (6.25-100 µM) for 12 h, or cotreatment of cells with cyanidin (3.13-100 µM) and MG, protected against cell cytotoxicity. In the cotreatment condition, cyanidin (33.3 and 100 µM) also decreased MG-induced apoptosis as determined by caspase-3 activity. Furthermore, INS-1 cells treated with MG increased the generation of reactive oxygen species (ROS) during a 6 h exposure. The MG-induced increase in ROS production was inhibited by cyanidin (33.3 and 100 µM) after 3 h stimulation. Furthermore, MG diminished the activity of glyoxalase 1 (Glo-1) and its gene expression as well as the level of total glutathione. In contrast, cyanidin reversed the inhibitory effect of MG on Glo-1 activity and glutathione levels. Interestingly, cyanidin alone was capable of increasing Glo-1 activity and glutathione levels without affecting Glo-1 mRNA expression. These findings suggest that cyanidin exerts a protective effect against MG-induced oxidative stress and apoptosis in pancreatic ß-cells by increasing the activity of Glo-1.


Asunto(s)
Antocianinas/farmacología , Apoptosis/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/fisiología , Lactoilglutatión Liasa/genética , Lactoilglutatión Liasa/metabolismo , Estrés Oxidativo/efectos de los fármacos , Piruvaldehído/efectos adversos , Animales , Caspasa 3/metabolismo , Células Cultivadas , Daño del ADN/efectos de los fármacos , Glutatión/metabolismo , Productos Finales de Glicación Avanzada/antagonistas & inhibidores , Productos Finales de Glicación Avanzada/metabolismo , Glicosilación/efectos de los fármacos , Ratas , Especies Reactivas de Oxígeno/metabolismo
17.
Nutrients ; 12(8)2020 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-32824545

RESUMEN

Riceberry rice (Oryza sativa L.) is a new pigmented variety of rice from Thailand. Despite its high anthocyanin content, its effect on adipogenesis and adipocyte function remains unexplored. We investigated whether Riceberry rice extract (RBE) impacted cell proliferation by examining viability and cell cycle, using preadipocyte 3T3-L1 cells. To test RBE's effect on adipocyte formation, cells were cultured in adipogenic medium supplemented with extract and adipocyte number and triglyceride levels were quantified. Furthermore, Akt1 phosphorylation along with RT-qPCR and intracellular calcium imaging were performed to obtain an insight into its mechanism of action. The effect of RBE on adipocyte function was investigated using glucose uptake and lipolysis assays. Treatment of cells with RBE decreased preadipocyte number without cytotoxicity despite inducing cell cycle arrest (p < 0.05). During adipogenic differentiation, RBE supplementation reduced adipocyte number and triglyceride accumulation by downregulating transcription factors (e.g., PPARγ, C/EBPα, and C/EBPß) and their target genes (p < 0.05). The Akt1 phosphorylation was decreased by RBE but insignificance, however, the extract failed to increase intracellular calcium signals. Finally, the treatment of adipocytes with RBE reduced glucose uptake by downregulating Glut4 mRNA expression and enhanced isoproterenol-induced lipolysis (p < 0.05). These findings suggest that RBE could potentially be used in the treatment of obesity by inhibiting adipocyte formation and proliferation.


Asunto(s)
Adipocitos/fisiología , Adipogénesis/efectos de los fármacos , Adipogénesis/genética , Antocianinas/farmacología , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Oryza/química , Extractos Vegetales/farmacología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Células 3T3-L1 , Animales , Antocianinas/aislamiento & purificación , Antocianinas/uso terapéutico , Proteína alfa Potenciadora de Unión a CCAAT/metabolismo , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Expresión Génica/efectos de los fármacos , Glucosa/metabolismo , Ratones , Obesidad/tratamiento farmacológico , Obesidad/etiología , PPAR gamma/metabolismo , Fitoterapia , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Triglicéridos/metabolismo
18.
Antimicrob Agents Chemother ; 53(7): 3024-9, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19398644

RESUMEN

The pharmacokinetics (PK) and pharmacodynamics (PD) of orbifloxacin were studied in beagle dogs after intravenous (i.v.) and intramuscular (i.m.) administration at a dose of 2.5 mg/kg body weight. An absolute bioavailability of 100.1% +/- 4.76%, a terminal half-life of 4.23 +/- 0.2 h and 3.95 +/- 0.15 h after i.v. and i.m. administration, a steady-state volume of distribution of 1.61 +/- 0.13 liters/kg, and clearance of 0.31 +/- 0.03 liters/h/kg were observed. Orbifloxacin showed rapid, concentration-dependent killing against the Escherichia coli, Staphylococcus aureus, Staphylococcus intermedius, and Proteus mirabilis clinical isolates. Computations based on PK-PD analysis indicated that the recommended dose is unlikely to be clinically effective against some strains like S. intermedius. Therefore, a higher dose of orbifloxacin would be worthy of consideration for treatment of certain bacterial infections in dogs.


Asunto(s)
Antiinfecciosos/farmacología , Antiinfecciosos/farmacocinética , Bacterias/efectos de los fármacos , Ciprofloxacina/análogos & derivados , Animales , Antiinfecciosos/administración & dosificación , Ciprofloxacina/administración & dosificación , Ciprofloxacina/farmacocinética , Ciprofloxacina/farmacología , Perros , Escherichia coli/efectos de los fármacos , Inyecciones Intramusculares , Inyecciones Intravenosas , Pruebas de Sensibilidad Microbiana , Proteus mirabilis/efectos de los fármacos , Staphylococcus/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos
19.
Microb Pathog ; 47(4): 196-201, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19596435

RESUMEN

In the present study we characterized the molecular mechanism by which esterase A (EstA) protein, a novel virulence factor of Streptococcus pneumoniae induces inflammation. Stimulation of RAW 264.7 macrophages with purified EstA protein induced the expression of inducible nitrogen oxide synthase (iNOS) mRNA and nitrogen oxide (NO) production in a concentration-dependent manner. Inhibitors of iNOS, NF-kappaB, p38 and ERK 1/2 MAPK pathways significantly decreased (50-78%) EstA-induced NO production. Similarly, EstA induced TNF-alpha, IL-1 beta and IL-6 mRNA expression in RAW 264.7 macrophages in a dose-dependent manner, and pre-treatment of the cell cultures with specific NF-kappaB, p38 and ERK 1/2 MAPK pathway inhibitors significantly decreased EstA-induced TNF-alpha, IL-1 beta and IL-6 protein production. Furthermore, immunoblot analysis revealed the degradation of the inhibitory kappa B (IKB-alpha) in response to EstA stimulation. Taken together, our data suggests that EstA protein is a novel inducer of NO and pro-inflammatory cytokines by activating the NF-kappaB, p38 and ERK 1/2 MAPK pathways during inflammatory responses. Future studies on the upstream protein kinases of the MAPK/NF-kappaB pathways and the kinetics of cytokine production will provide further details into the mechanism of EstA-induced inflammatory response.


Asunto(s)
Proteínas Bacterianas/inmunología , Hidrolasas de Éster Carboxílico/inmunología , Citocinas/biosíntesis , Macrófagos/microbiología , FN-kappa B/metabolismo , Óxido Nítrico/biosíntesis , Streptococcus pneumoniae/inmunología , Factores de Virulencia/inmunología , Animales , Perfilación de la Expresión Génica , Immunoblotting , Ratones , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
20.
Cell Calcium ; 41(1): 51-61, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16806463

RESUMEN

TRPM4 is a calcium-activated non-selective cation channel that is widely expressed and proposed to be involved in cell depolarization. In excitable cells, TRPM4 may regulate calcium influx by causing the depolarization that drives the activation of voltage-dependent calcium channels. We here report that insulin-secreting cells of the rat pancreatic beta-cell line INS-1 natively express TRPM4 proteins and generate large depolarizing membrane currents in response to increased intracellular calcium. These currents exhibit the characteristics of TRPM4 and can be suppressed by expressing a dominant negative TRPM4 construct, resulting in significantly decreased insulin secretion in response to a glucose stimulus. Reduced insulin secretion was also observed with arginine vasopressin stimulation, a Gq-coupled receptor agonist in beta-cells. Moreover, the recruitment of TRPM4 currents was biphasic in both INS-1 cells as well as HEK-293 cells overexpressing TRPM4. The first phase is due to activation of TRPM4 channels localized within the plasma membrane followed by a slower secondary phase, which is caused by the recruitment of TRPM4-containing vesicles to the plasma membrane during exocytosis. The secondary phase can be observed during perfusion of cells with increasing [Ca(2+)](i), replicated with agonist stimulation, and coincides with an increase in cell capacitance, loss of FM1-43 dye, and vesicle fusion. Our data suggest that TRPM4 may play a key role in the control of membrane potential and electrical activity of electrically excitable secretory cells and the dynamic translocation of TRPM4 from a vesicular pool to the plasma membrane via Ca(2+)-dependent exocytosis may represent a key short- and midterm regulatory mechanism by which cells regulate electrical activity.


Asunto(s)
Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Canales Catiónicos TRPM/metabolismo , Animales , Señalización del Calcio , Línea Celular , Exocitosis , Glucosa/farmacología , Humanos , Secreción de Insulina , Células Secretoras de Insulina/efectos de los fármacos , Potenciales de la Membrana , Ratas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Canales Catiónicos TRPM/genética
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