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1.
Dis Colon Rectum ; 65(2): e80-e84, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34840298

RESUMO

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.


Assuntos
Doenças do Colo/patologia , Colonoscopia/instrumentação , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/instrumentação , Endossonografia/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças do Colo/diagnóstico por imagem , Colonoscopia/efeitos adversos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/efeitos adversos , Endossonografia/efeitos adversos , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
2.
J Cell Physiol ; 235(2): 1723-1732, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31301074

RESUMO

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.


Assuntos
Trifosfato de Adenosina/farmacologia , Sinalização do Cálcio/fisiologia , Polpa Dentária/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/metabolismo , Animais , Sinalização do Cálcio/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Polpa Dentária/citologia , Polpa Dentária/efeitos dos fármacos , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteogênese/genética , Osteogênese/fisiologia , Ratos , Ratos Sprague-Dawley , Fosfolipases Tipo C/metabolismo
3.
Biol Reprod ; 99(6): 1159-1170, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29982498

RESUMO

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.


Assuntos
Cálcio/metabolismo , Peixes/fisiologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Viviparidade não Mamífera/fisiologia , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Cloreto de Cálcio/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Feminino , Concentração de Íons de Hidrogênio , Masculino , Espermatozoides/fisiologia
4.
Am J Physiol Endocrinol Metab ; 311(2): E530-41, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27436609

RESUMO

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.


Assuntos
Adipócitos Brancos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Fibronectinas/farmacologia , Mitocôndrias/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , RNA Mensageiro/efeitos dos fármacos , Termogênese/efeitos dos fármacos , Adipócitos Marrons/efeitos dos fármacos , Adipócitos Marrons/metabolismo , Adipócitos Brancos/metabolismo , Adipogenia/genética , Adolescente , Adulto , Idoso , Western Blotting , Respiração Celular/efeitos dos fármacos , Células Cultivadas , Exercício Físico , MAP Quinases Reguladas por Sinal Extracelular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Obesidade/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteogênese/genética , Fosfoproteínas/efeitos dos fármacos , Fosfoproteínas/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fator de Transcrição STAT3/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Gordura Subcutânea/citologia , Termogênese/genética , Proteína Desacopladora 1/efeitos dos fármacos , Proteína Desacopladora 1/metabolismo , Regulação para Cima , Adulto Jovem , Proteínas Quinases p38 Ativadas por Mitógeno/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
J Cell Sci ; 126(Pt 16): 3638-48, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23750005

RESUMO

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.


Assuntos
Hepatócitos/citologia , Células Secretoras de Insulina/citologia , Animais , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Células Cultivadas , Metilação de DNA , Hepatócitos/metabolismo , Proteínas de Homeodomínio/genética , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Regiões Promotoras Genéticas , Ratos , Células-Tronco/citologia , Células-Tronco/metabolismo , Transativadores/genética
6.
Biochem J ; 463(1): 123-34, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25001294

RESUMO

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.


Assuntos
Adipogenia/fisiologia , Tecido Adiposo/metabolismo , Sinalização do Cálcio/fisiologia , Histamina/metabolismo , Células-Tronco/metabolismo , Canais de Cátion TRPM/biossíntese , Tecido Adiposo/citologia , Adulto , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Células Cultivadas , Regulação da Expressão Gênica/fisiologia , Histamina/genética , Humanos , Masculino , Pessoa de Meia-Idade , Receptores Histamínicos H1/genética , Receptores Histamínicos H1/metabolismo , Células-Tronco/citologia , Canais de Cátion TRPM/genética
7.
Stem Cells ; 31(1): 167-77, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23081848

RESUMO

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.


Assuntos
Canais de Cálcio/metabolismo , Saco Dentário/metabolismo , Células-Tronco/metabolismo , Canais de Cátion TRPM/metabolismo , Adipogenia/fisiologia , Animais , Cálcio/metabolismo , Sinalização do Cálcio , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Potenciais da Membrana , Osteogênese/fisiologia , Técnicas de Patch-Clamp , Interferência de RNA , RNA Interferente Pequeno , Ratos , Ratos Sprague-Dawley , Canais de Cátion TRPM/genética , Dente/metabolismo
8.
Fish Shellfish Immunol ; 34(3): 756-61, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23261510

RESUMO

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).


Assuntos
Anguilla/crescimento & desenvolvimento , Anguilla/imunologia , Infecções por Enterobacteriaceae/veterinária , Doenças dos Peixes/imunologia , Imunidade Inata , Lactobacillus/metabolismo , Anguilla/microbiologia , Animais , Antioxidantes/metabolismo , Dieta/veterinária , Edwardsiella tarda/fisiologia , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/microbiologia , Doenças dos Peixes/microbiologia , Lactobacillus/isolamento & purificação , Probióticos/administração & dosagem
9.
Differentiation ; 83(5): 233-41, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22466603

RESUMO

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.


Assuntos
Diferenciação Celular , Terapia Baseada em Transplante de Células e Tecidos , Células-Tronco Embrionárias/citologia , Neurônios GABAérgicos/citologia , Tretinoína/farmacologia , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Corpos Embrioides/citologia , Corpos Embrioides/metabolismo , Células-Tronco Embrionárias/transplante , Neurônios GABAérgicos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Fator Inibidor de Leucemia/metabolismo , Camundongos , Canais de Potássio/metabolismo , Ácido gama-Aminobutírico/metabolismo
10.
Molecules ; 18(11): 13886-903, 2013 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-24284487

RESUMO

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.


Assuntos
Ácidos Cumáricos/química , Monossacarídeos/química , Soroalbumina Bovina/química , Animais , Bovinos , Produtos Finais de Glicação Avançada/química , Glicosilação , Oxirredução
11.
Biomed Pharmacother ; 162: 114677, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37044024

RESUMO

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.


Assuntos
Adipogenia , Antocianinas , Camundongos , Animais , Antocianinas/farmacologia , Células 3T3-L1 , Fosfolipases Tipo C/metabolismo , Regulação para Baixo , Diferenciação Celular , Obesidade/metabolismo , PPAR gama/metabolismo
12.
Int J Biol Macromol ; 223(Pt A): 1578-1585, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36375667

RESUMO

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.


Assuntos
Antocianinas , Insulina , Animais , Camundongos , Antocianinas/farmacologia , Antocianinas/química , Células 3T3-L1 , Glicosídeos , Estrutura Secundária de Proteína
13.
Biomed Pharmacother ; 146: 112494, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34891116

RESUMO

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.


Assuntos
Antocianinas/farmacologia , Secreção de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Animais , Cálcio/metabolismo , Canais de Cálcio Tipo L/genética , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Transportador de Glucose Tipo 2/genética , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Células Secretoras de Insulina/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/genética , Ratos , Fosfolipases Tipo C/metabolismo
14.
Food Funct ; 13(9): 5166-5176, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35421887

RESUMO

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.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Rubus , Ácido 3,4-Di-Hidroxifenilacético , Biomarcadores , Diabetes Mellitus Tipo 2/tratamento farmacológico , Promoção da Saúde , Humanos , Inflamação/tratamento farmacológico , Insulina , Projetos Piloto , Polifenóis/farmacologia
15.
Microb Pathog ; 51(4): 297-303, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21477644

RESUMO

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.


Assuntos
Proteínas de Bactérias/toxicidade , Hidrolases de Éster Carboxílico/toxicidade , Citocinas/biossíntese , Janus Quinase 2/metabolismo , Macrófagos/imunologia , Macrófagos/microbiologia , Streptococcus pneumoniae/patogenicidade , Animais , Western Blotting , Linhagem Celular , Perfilação da Expressão Gênica , Camundongos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Fatores de Tempo
16.
Nutrients ; 12(5)2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32384625

RESUMO

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.


Assuntos
Antocianinas/farmacologia , Apoptose/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/fisiologia , Lactoilglutationa Liase/genética , Lactoilglutationa Liase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Aldeído Pirúvico/efeitos adversos , Animais , Caspase 3/metabolismo , Células Cultivadas , Dano ao DNA/efeitos dos fármacos , Glutationa/metabolismo , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Produtos Finais de Glicação Avançada/metabolismo , Glicosilação/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo
17.
Nutrients ; 12(8)2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32824545

RESUMO

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.


Assuntos
Adipócitos/fisiologia , Adipogenia/efeitos dos fármacos , Adipogenia/genética , Antocianinas/farmacologia , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Oryza/química , Extratos Vegetais/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Células 3T3-L1 , Animais , Antocianinas/isolamento & purificação , Antocianinas/uso terapêutico , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Camundongos , Obesidade/tratamento farmacológico , Obesidade/etiologia , PPAR gama/metabolismo , Fitoterapia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Triglicerídeos/metabolismo
18.
Antimicrob Agents Chemother ; 53(7): 3024-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19398644

RESUMO

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.


Assuntos
Anti-Infecciosos/farmacologia , Anti-Infecciosos/farmacocinética , Bactérias/efeitos dos fármacos , Ciprofloxacina/análogos & derivados , Animais , Anti-Infecciosos/administração & dosagem , Ciprofloxacina/administração & dosagem , Ciprofloxacina/farmacocinética , Ciprofloxacina/farmacologia , Cães , Escherichia coli/efeitos dos fármacos , Injeções Intramusculares , Injeções Intravenosas , Testes de Sensibilidade Microbiana , Proteus mirabilis/efeitos dos fármacos , Staphylococcus/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
19.
Microb Pathog ; 47(4): 196-201, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19596435

RESUMO

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.


Assuntos
Proteínas de Bactérias/imunologia , Hidrolases de Éster Carboxílico/imunologia , Citocinas/biossíntese , Macrófagos/microbiologia , NF-kappa B/metabolismo , Óxido Nítrico/biossíntese , Streptococcus pneumoniae/imunologia , Fatores de Virulência/imunologia , Animais , Perfilação da Expressão Gênica , Immunoblotting , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
20.
Cell Calcium ; 41(1): 51-61, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16806463

RESUMO

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.


Assuntos
Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Canais de Cátion TRPM/metabolismo , Animais , Sinalização do Cálcio , Linhagem Celular , Exocitose , Glucose/farmacologia , Humanos , Secreção de Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Potenciais da Membrana , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Canais de Cátion TRPM/genética
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