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1.
Biosci Biotechnol Biochem ; 87(11): 1364-1372, 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37673677

RESUMEN

Scalp bacteria on the human scalp and scalp hair comprise distinct community structures for sites and individuals. To evaluate their effect on human keratinocyte cellular activity, including that of the hair follicular keratinocytes, the expression of several longevity genes was examined using HaCaT cells. A screening system that uses enhanced green fluorescent protein (EGFP) fluorescence was established to identify scalp bacteria that enhance silent mating type information regulation 2 homolog-1 (SIRT1) promoter activity in transformed HaCaT cells (SIRT1p-EGFP). The results of quantitative polymerase chain reaction revealed that several predominant scalp bacteria enhanced (Cutibacterium acnes and Pseudomonas lini) and repressed (Staphylococcus epidermidis) the expressions of SIRT1 and telomerase reverse transcriptase (TERT) genes in HaCaT cells. These results suggest that the predominant scalp bacteria are related to the health of the scalp and hair, including repair of the damaged scalp and hair growth, by regulating gene expression in keratinocytes.


Asunto(s)
Cuero Cabelludo , Telomerasa , Humanos , Sirtuina 1/genética , Sirtuina 1/metabolismo , Queratinocitos/metabolismo , Cabello , ARN Polimerasas Dirigidas por ADN/metabolismo , Bacterias/metabolismo , Telomerasa/genética , Telomerasa/metabolismo
2.
Molecules ; 28(11)2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37299024

RESUMEN

Hericium erinaceus, a mushroom species commonly known as Yamabushitake in Japan, is known to have a stimulatory effect on neurotrophic factors, such as brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF). Hericenone C, a meroterpenoid with palmitic acid as the fatty acid side chain, is reported to be one such stimulant. However, according to the structure of the compound, the fatty acid side chain seems highly susceptible to lipase decomposition, under in vivo metabolic conditions. To study this phenomenon, hericenone C from the ethanol extract of the fruiting body was subjected to lipase enzyme treatment and observed for changes in the chemical structure. The compound formed after the lipase enzyme digestion was isolated and identified using LC-QTOF-MS combined with 1H-NMR analysis. It was found to be a derivative of hericenone C without its fatty acid side chain and was named deacylhericenone. Interestingly, a comparative investigation of the neuroprotective properties of hericenone C and deacylhericenone showed that the BDNF mRNA expression in human astrocytoma cells (1321N1) and the protection against H2O2-induced oxidative stress was considerably higher in the case of deacylhericenone. These findings suggest that the stronger bioactive form of the hericenone C compound is in fact deacylhericenone.


Asunto(s)
Agaricales , Factor Neurotrófico Derivado del Encéfalo , Humanos , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Lipasa , Agaricales/química , Ácidos Grasos
3.
Molecules ; 27(7)2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35408452

RESUMEN

Cistus L. is a genus of dicotyledonous perennial herbaceous plants. Cistus species have been commonly used in folk medicine in the Mediterranean region. In the present study, the biological activities of essential oils derived from Cistus species (Cistus laurifolius, C. monspeliensis, C. creticus, and C. salviifolius) were evaluated. Essential oils derived from C. laurifolius and C. monspeliensis were found to augment the expression of SIRT1, an anti-aging gene, in the normal culture of HaCaT cells. Furthermore, these essential oils increased the number and size of mitochondria and augmented their activity. These effects were thought to be caused by the up- and downregulated expression of MITOL and Drp1 in HaCaT cells, respectively, in response to the essential oil treatment. In addition, these essential oils were found to attenuate ultraviolet-B-induced mitochondrial damage and cellular senescence in HaCaT cells. These findings indicate that essential oils derived from C. laurifolius and C. monspeliensis may inhibit skin aging through mitochondrial regulation via SIRT1 activation.


Asunto(s)
Cistus , Aceites Volátiles , Humanos , Queratinocitos , Mitocondrias , Aceites Volátiles/farmacología , Sirtuina 1/genética
4.
Lab Invest ; 101(1): 38-50, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32901097

RESUMEN

Epidermal growth factor receptor (EGFR) is highly expressed in several types of cancer cells including oral squamous cell carcinoma (OSCC). EGF/EGFR signaling is recognized as an important molecular target in cancer therapy. However, cancer cells often become tolerant to EGF/EGFR signaling-targeted therapies. In the tumor microenvironment, the tumor incites inflammation and the inflammation-derived cytokines make a considerable impact on cancer development. In addition, hyperosmolarity is also induced, but the role of osmotic stress in cancer development has not been fully understood. This study demonstrates molecular insights into hyperosmolarity effect on OSCC development and shows that NFAT5 transcription factor plays an important functional role in enhancing the oral cancer cell proliferation by inducing the EGFR translocation from the endoplasmic reticulum to the plasma membrane through increase the expression of DPAGT1, an essential enzyme for catalyzing the first committed step of N-linked protein glycosylation. These results suggest that hyperosmolarity-induced intra-nuclear translocation of NFAT5 essential for DPAGT1 activation and EGFR subcellular translocation responsible for OSCC tumor progression.


Asunto(s)
N-Acetilglucosaminiltransferasas/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Neoplasias de la Lengua/metabolismo , Factores de Transcripción/metabolismo , Línea Celular Tumoral , Receptores ErbB/metabolismo , Humanos , Presión Osmótica , Microambiente Tumoral
5.
Am J Epidemiol ; 188(9): 1637-1645, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-31127276

RESUMEN

We examined the association between serum concentrations of ß-alanine, a metabolite of carnosine and anserine, and the risk of dementia in a general population of elderly Japanese persons. In 2007, 1,475 residents of Hisayama, Japan, aged 60-79 years and without dementia were divided into 4 groups according to quartiles of serum ß-alanine concentrations (quartile 1, lowest; quartile 4, highest) and followed for a median of 5.3 years. During follow-up, 117 subjects developed all-cause dementia (Alzheimer in 77 cases and vascular dementia in 31). The risk of all-cause dementia decreased with increasing serum ß-alanine levels after adjustment for potential confounding factors (quartile 2, hazard ratio (HR) = 0.73 (95% confidence interval (CI): 0.45, 1.18); quartile 3, HR = 0.50 (95% CI: 0.28, 0.89); quartile 4, HR = 0.50 (95% CI: 0.27, 0.92); P = 0.01 for trend). A similar inverse association was observed for Alzheimer disease (quartile 2, HR = 0.78 (95% CI: 0.44, 1.38); quartile 3, HR = 0.53 (95% CI: 0.26, 1.06); quartile 4, HR = 0.53 (95% CI: 0.25, 1.10); P = 0.04 for trend) but not for vascular dementia. We found that higher serum ß-alanine levels were significantly associated with lower risks of all-cause dementia and Alzheimer disease. Because serum ß-alanine levels reflect intakes of carnosine/anserine, higher intakes of carnosine/anserine might be beneficial for the prevention of dementia.


Asunto(s)
Demencia/sangre , beta-Alanina/sangre , Anciano , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/epidemiología , Demencia/epidemiología , Demencia Vascular/sangre , Demencia Vascular/epidemiología , Humanos , Incidencia , Japón/epidemiología , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo
6.
Biosci Biotechnol Biochem ; 82(4): 683-688, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29224504

RESUMEN

Carnosine (ß-Ala-l-His), an imidazole dipeptide, is known to have many functions. Recently, we demonstrated in a double-blind randomized controlled trial that carnosine is capable of preserving cognitive function in elderly people. In the current study, we assessed the ability of carnosine to activate the brain, and we tried to clarify the molecular mechanisms behind this activation. Our results demonstrate that carnosine permeates the blood brain barrier and activates glial cells within the brain, causing them to secrete neurotrophins, including BDNF and NGF. These results point to a novel mechanism of carnosine-induced neuronal activation. Our results suggest that carnosine should be recognized as a functional food factor that helps achieve anti-brain aging.


Asunto(s)
Encéfalo/efectos de los fármacos , Carnosina/farmacología , Neuronas/efectos de los fármacos , Barrera Hematoencefálica , Encéfalo/citología , Encéfalo/metabolismo , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Carnosina/farmacocinética , Línea Celular Tumoral , Medios de Cultivo , Alimentos Funcionales , Expresión Génica/efectos de los fármacos , Humanos , Factor de Crecimiento Nervioso/genética , Factor de Crecimiento Nervioso/metabolismo , Neuritas/efectos de los fármacos , Permeabilidad
7.
Molecules ; 20(3): 4813-32, 2015 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-25786165

RESUMEN

Angelica shikokiana is widely marketed in Japan as a dietary food supplement. With a focus on neurodegenerative conditions such as Alzheimer's disease, the aerial part was extracted and through bio-guided fractionation, fifteen compounds [α-glutinol, ß-amyrin, kaempferol, luteolin, quercetin, kaempferol-3-O-glucoside, kaempferol-3-O-rutinoside, methyl chlorogenate, chlorogenic acid, hyuganin E, 5-(hydroxymethyl)-2-furaldehyde, ß-sitosterol-3-O-glucoside, adenosine (isolated for the first time from A. shikokiana), isoepoxypteryxin and isopteryxin] were isolated. Isolated compounds were evaluated for in vitro neuroprotection using acetylcholine esterase inhibitory, protection against hydrogen peroxide and amyloid ß peptide (Aß25-35)-induced neurotoxicity in neuro-2A cells, scavenging of hydroxyl radicals and intracellular reactive oxygen species and thioflavin T assays. Quercetin showed the strongest AChE inhibition (IC50 value = 35.5 µM) through binding to His-440 and Tyr-70 residues at the catalytic and anionic sites of acetylcholine esterase, respectively. Chlorogenic acid, its methyl ester, quercetin and luteolin could significantly protect neuro-2A cells against H2O2-induced neurotoxicity and scavenge hydroxyl radical and intracellular reactive oxygen species. Kaempferol-3-O-rutinoiside, hyuganin E and isoepoxypteryxin significantly decreased Aß25-35-induced neurotoxicity and Th-T fluorescence. To the best of our knowledge, this is the first report about neuroprotection of hyuganin E and isoepoxypteryxin against Aß25-35-induced neurotoxicity.


Asunto(s)
Angelica/química , Neoplasias Encefálicas/tratamiento farmacológico , Neuroblastoma/tratamiento farmacológico , Fármacos Neuroprotectores/aislamiento & purificación , Fármacos Neuroprotectores/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Péptidos beta-Amiloides/toxicidad , Animales , Línea Celular Tumoral , Peróxido de Hidrógeno/toxicidad , Técnicas In Vitro , Japón , Ratones , Fármacos Neuroprotectores/química , Fragmentos de Péptidos/toxicidad , Componentes Aéreos de las Plantas/química , Quercetina/aislamiento & purificación , Quercetina/farmacología , Especies Reactivas de Oxígeno/metabolismo
8.
Bioorg Med Chem ; 22(1): 211-20, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-24326278

RESUMEN

Semisynthetic reactions were conducted on oleanolic acid, a common plant-derived oleanane-type triterpene. Ten rationally designed derivatives of oleanolic acid were synthesized based on docking studies and tested for their topoisomerase I and IIα inhibitory activity. Semisynthetic reactions targeted C-3, C-12, C-13, and C-17. Nine of the synthesized compounds were identified as new compounds. The structures of these compounds were confirmed by spectroscopic methods (1D, 2D NMR and MS). Five oleanolic acid analogues (S2, S3, S5, S7 and S9) showed higher activity than camptothecin (CPT) in the topoisomerase I DNA relaxation assay. Four oleanolic acid analogues (S2, S3, S5 and S6) showed higher activity than etoposide in a topoisomerase II assay. The results indicated that the C12-C13 double bond of the oleanolic acid skeleton is important for the inhibitory activity against both types of topoisomerases, while insertion of a longer chain at either position 3 or 17 increases the activity against topoisomerases by various degrees. Some of the synthesized compounds act as dual inhibitors for both topoisomerase I and IIα.


Asunto(s)
Antineoplásicos/farmacología , Ácido Oleanólico/análogos & derivados , Inhibidores de Topoisomerasa I/síntesis química , Inhibidores de Topoisomerasa II/síntesis química , Humanos , Modelos Moleculares , Ácido Oleanólico/metabolismo , Inhibidores de Topoisomerasa I/química , Inhibidores de Topoisomerasa II/química
9.
Heliyon ; 10(5): e26915, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38444511

RESUMEN

The number of patients with allergies to pollen and food is increasing worldwide. In Japan, the prevalence of cedar pollinosis, a type I allergy, is nearly 30% and accounts of hay fever are rising. A potential natural remedy for these allergic diseases may be Hita Tenryo Water™ (referred to simply as Hita Tenryo water), water that is pumped from deep underground in the Hita region of Oita, Japan, which has been the subject of various research reports. Here, we investigated the potential of using Hita Tenryo water to suppress the onset of cedar pollinosis in a mouse model and explored the immunological mechanism of the suppression. Test model mice were given Hita Tenryo water ad libitum to drink and received intraperitoneal administration of (i) tap water (Hw1), (ii) 25% Hita Tenryo water (Hw2) or (iii) 100% Hita Tenryo (Hw3). There were no significant differences in body weight change, feed intake, or water intake among the groups during the experimental period. We examined nose rubbing and sneezing as allergic symptoms. The frequency of rubbing and sneezing tended to decrease in the Hw1 and Hw2 group, and significantly decreased in the Hw3 group compared to control. Total IgE levels in serum were also significantly reduced in Hita Tenryo water intraperitoneal administration groups. In vitro examination of the rate of release of ß-hexosaminidase from BL-2H3 cells showed that there were no significantly differences between Hita Tenryo water-treated and control cells. In addition, measurement of Th2-related cytokine levels in concanavalin A-stimulated peripheral blood mononuclear cells revealed a significant decrease in IL-4, IL-6, and IL-10 levels in medium (p < 0.01). In contrast, production of IFN-γ significantly increased (p < 0.01). These results indicate that Hita Tenryo water may alleviate and/or suppress allergic symptoms.

10.
Cytotechnology ; 76(2): 209-216, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38495295

RESUMEN

Fructobacillus is a lactic-acid bacterium recently identified in fructose-rich environments. Fructobacillus is also known to exhibit unusual growth characteristics due to an incomplete gene encoding alcohol/acetaldehyde hydrogenase, which results in an imbalance in the nicotinamide adenine mononucleotide (NAD+)/NADN levels. Recently, the addition of d-fructose to the culture medium of Fructobacillus strains increased the intracellular nicotinamide mononucleotide (NMN) content. In the present study, we evaluated the functionality of Fructobacillus that produces high levels of NMN, using one substrain (Fructobacillus fructosus OS-1010). Therefore, in this study, we examined its functionality in the interaction between intestinal cells and muscle cells. The results showed that supernatant derived from intestinal epithelial cells (Caco-2 cells) treated with F. fructosus OS-1010 activated muscle cells (C2C12 cells). Further analysis revealed that Caco-2 cells treated with F. fructosus OS-1010 secreted exosomes known as extracellular vesicles, which activated the muscle cells. Furthermore, pathway analysis of the target genes of miRNA in exosomes revealed that pathways involved in muscle cell activation, including insulin signaling and cardiac muscle regulation, neurotrophic factors, longevity, and anti-aging, can be activated by exosomes. In other words, F. fructosus OS-1010 could activate various cells such as the skin and muscle cells, by secreting functional exosomes from the intestinal tract.

11.
Sci Rep ; 14(1): 13797, 2024 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-38877139

RESUMEN

In filamentous fungi, microtubules are important for polar growth and morphological maintenance and serve as rails for intracellular trafficking. The molecular mechanisms associated with microtubules have been analyzed. However, little is known about when and where tubulin, a component of microtubules, is biosynthesized in multinuclear and multicellular filamentous fungi. In this study, we visualized microtubules based on the enhanced green fluorescence protein (EGFP)-labeled α-tubulin and ß-tubulin mRNA tagged by the EGFP-mediated MS2 system in living yellow Koji mold Aspergillus oryzae cells in order to understand the spatiotemporal production mechanism of tubulin. We found that mRNA of btuA, encoding for ß-tubulin, localized at dot-like structures through the apical, middle and basal regions of the hyphal cells. In addition, some btuA mRNA dots showed microtubule-dependent motor protein-like dynamics in the cells. Furthermore, it was found that btuA mRNA dots were decreased in the cytoplasm just before mitosis but increased immediately after mitosis, followed by a gradual decrease. In summary, the localization and abundance of ß-tubulin mRNA is spatiotemporally regulated in living A. oryzae hyphal cells.


Asunto(s)
Aspergillus oryzae , Microtúbulos , ARN Mensajero , Tubulina (Proteína) , Aspergillus oryzae/genética , Aspergillus oryzae/metabolismo , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Microtúbulos/metabolismo , Hifa/genética , Hifa/metabolismo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Regulación Fúngica de la Expresión Génica , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
12.
Biochem Biophys Res Commun ; 441(1): 59-64, 2013 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-24140057

RESUMEN

Antibody display methods are increasingly being used to produce human monoclonal antibodies for disease therapy. Rapid screening and isolation of specific human antibody genes are valuable for producing human monoclonal antibodies showing high specificity and affinity. In this report, we describe a novel mammalian cell display method in which whole human IgG is displayed on the cell surface of CHO cells. Cells expressing antigen-specific human monoclonal IgGs with high affinity on the cell surface after normal folding and posttranscriptional modification were screened using a cell sorter. The membrane-type IgG-expressing CHO cells were then converted to IgG-secreting cells by transfection with a plasmid coding Cre recombinase. This mammalian cell display method was applied to in vitro affinity maturation of monoclonal C9 IgG specific to the human high-affinity IgE receptor (FcεRIα). The CDR3 of the C9 heavy chain variable region gene was randomly mutated and inserted into pcDNA5FRT/IgG. A C9 IgG (CDRH3r)-expressing CHO cell display library consisting of 1.1×10(6) independent clones was constructed. IgG-displaying cells showing high reactivity to FcεRIα antigen were screened by the cell sorter, resulting in the establishment of a CHO cell line producing with higher reactivity than the parent C9 IgG.


Asunto(s)
Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/aislamiento & purificación , Técnicas de Visualización de Superficie Celular/métodos , Secuencia de Aminoácidos , Animales , Células Productoras de Anticuerpos/metabolismo , Células CHO , Membrana Celular/metabolismo , Cricetinae , Cricetulus , Conversión Génica , Humanos , Inmunoglobulina G/metabolismo , Datos de Secuencia Molecular , Biblioteca de Péptidos , Receptores de IgE/química , Receptores de IgE/metabolismo , Recombinación Genética/genética , Transgenes
13.
Methods ; 56(3): 383-8, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22406489

RESUMEN

Until now, various stimuli as well as serial passaging have been known to induce cellular senescence in normal human diploid fibroblasts. However, in many cases, we have encountered difficulty in quantitatively analyzing the cellular senescence phenotypes of senescent cells in a physiological condition. High-content screening (HCS)-based image analysis is becoming an important and powerful research tool. In the present study, an automated and quantitative cellular image-analysis system was employed to quantify the cellular senescence phenotypes induced in normal human diploid fibroblasts, TIG-1 cells, and found to be a powerful tool in the cellular senescence study.


Asunto(s)
Senescencia Celular , Citometría de Imagen/métodos , Células Cultivadas , Humanos , Fenotipo
14.
Nutrients ; 15(6)2023 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-36986209

RESUMEN

Carnosine is known to improve brain function. The molecular basis for the carnosine-mediated interaction between intestinal cells and neuronal cells is that carnosine acts on intestinal cells and stimulates exosome secretion, which can induce neurite outgrowth in neuronal cells. This study aimed to infer the carnosine-mediated interaction between muscle cells and neuronal cells. The results revealed that carnosine induces muscle cell differentiation, as well as the secretion of exosomes and myokines that can act on neuronal cells. Carnosine acts not only on intestinal cells but also on muscle cells, stimulating the secretion of secretory factors including exosomes that induce neurite outgrowth in neuronal cells, as well as myokines known to be involved in neuronal cell activation. As the miRNAs in exosomes secreted from intestinal cells and muscle cells upon carnosine treatment are different, it could be assumed that carnosine acts on each cell to interact with neuronal cell through separate factors and mechanisms.


Asunto(s)
Carnosina , MicroARNs , Carnosina/farmacología , Carnosina/metabolismo , Neuronas/metabolismo , Encéfalo/metabolismo , Músculos/metabolismo
15.
Biochem Biophys Res Commun ; 417(1): 630-4, 2012 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-22197555

RESUMEN

SIRT1, the mammalian homolog of sirtuins, has emerged as a mediator of the beneficial effects of calorie restriction. Among them, we focused on the SIRT1-induced prevention of cellular senescence, and tried to reveal the molecular mechanisms that define the effects of SIRT1. Firstly in this study, we observed that overexpression of SIRT1 resulted in the prevention of cellular senescence of normal human umbilical cord fibroblast HUC-F2 cells. Here, we focused on the human telomerase reverse transcriptase (hTERT) gene as a target of the SIRT1-induced prevention of cellular senescence. Results showed that SIRT1, SIRT1 activator, resveratrol, and SIRT1 activating condition, starved condition, increased the transcription of hTERT in HUC-F2 cells. Next, we found that SIRT1 increased hTERT transcription in a c-MYC-dependent manner, triggered the transcription of the c-MYC gene and increased the amount of c-MYC recruited to the hTERT promoter. Further, SIRT1 increased the transcriptional activation ability of c-MYC and correspondingly increased the amount of acetylated H4 histone at the hTERT promoter. All of these results indicated that SIRT1 activates hTERT transcription through the involvement of c-MYC, and suggested that this SIRT1-induced augmentation of hTERT transcription resulted in the extension of the cellular life span of HUC-F2 cells.


Asunto(s)
Senescencia Celular/genética , Regulación Enzimológica de la Expresión Génica , Sirtuina 1/metabolismo , Telomerasa/genética , Transcripción Genética , Células Cultivadas , Fibroblastos/enzimología , Fibroblastos/fisiología , Humanos , Proteínas Proto-Oncogénicas c-myc/metabolismo , Sirtuina 1/genética , Cordón Umbilical/citología , Cordón Umbilical/enzimología , Cordón Umbilical/fisiología
16.
Cytotechnology ; 74(2): 319-327, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35464165

RESUMEN

This study aimed to investigate the changes in B cell functional decline and antigen sensitization with aging using two Epstein Barr virus (EBV)-immortalized human B cell lines, one from a 22-year-old man (EBV-B young) and the other from a 65-year-old man (EBV-B old). The activity of senescence-associated ß-galactosidase, a marker of cellular senescence, was enhanced in the EBV-B old cells compared with EBV-B young cells. Moreover, the levels of p16, p21, IL-6, TNF-α, and TGF-ß1, which are senescence-associated secretary phenotypes, were also increased in EBV-B old cells. In vitro immunization of EBV-B cells with ß-lactoglobulin further showed that EBV-B old cells had a reduced cell population of naïve B cells than that of EBV-B young cells. Furthermore, HLA-DR expression, which is important for antigen presentation, was decreased in the EBV-B old cells. Comparative microarray analysis between EBV-B young and old cells also showed decreased expression of antibody genes, such as those of the heavy chain and light chain (κ chain). These results suggest that cellular senescence and decreased gene expression are responsible, at least in part, for the decline in B cell function and antigen sensitization capacity with aging, which ultimately impairs the function of the acquired immune system.

17.
Nutrients ; 14(14)2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35889819

RESUMEN

Regulatory T cells (Tregs) and CD4+/CD25+ T cells play an important role in the suppression of excessive immune responses, homeostasis of immune function, and oral tolerance. In this study, we screened for food-derived polyphenols that induce Tregs in response to retinaldehyde dehydrogenase (RALDH2) activation using macrophage-like THP-1 cells. THP-1 cells were transfected with an EGFP reporter vector whose expression is regulated under the control of mouse Raldh2 promoter and named THP-1 (Raldh2p-EGFP) cells. The THP-1 (Raldh2p-EGFP) cells were treated with 33 polyphenols after inducing their differentiation into macrophage-like cells using phorbol 12-myristate 13-acetate. Of the 33 polyphenols, five (kaempferol, quercetin, morin, luteolin and fisetin) activated Raldh2 promoter activity, and both quercetin and luteolin activated the endogenous Raldh2 mRNA expression and enzymatic activity. Furthermore, these two polyphenols increased transforming growth factor beta 1 and forkhead box P3 mRNA expression, suggesting that they have Treg-inducing ability. Finally, we verified that these polyphenols could induce Tregs in vivo and consequently induce IgA production. Oral administration of quercetin and luteolin increased IgA production in feces of mice. Therefore, quercetin and luteolin can induce Tregs via RALDH2 activation and consequently increase IgA production, suggesting that they can enhance intestinal barrier function.


Asunto(s)
Polifenoles , Linfocitos T Reguladores , Aldehído Oxidorreductasas/metabolismo , Animales , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Inmunoglobulina A/metabolismo , Luteolina/farmacología , Ratones , Polifenoles/farmacología , Quercetina/farmacología , ARN Mensajero/metabolismo
18.
Sci Rep ; 12(1): 12427, 2022 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-35859106

RESUMEN

We examined the association of serum s-adenosylmethionine (SAM), s-adenosylhomocysteine (SAH) (methionine metabolites), and their ratio on the risk of dementia and death in a community-dwelling population of older Japanese individuals. 1371 residents of Hisayama, Japan, aged 65 years or older and without dementia, were followed for a median of 10.2 years (2007-2017). We divided serum SAM, SAH, and SAM/SAH ratio into quartiles. Cox proportional hazards models were used to estimate the hazard ratios (HRs) and their 95% confidence intervals (CIs) of serum SAM, SAH, and SAM/SAH ratio levels on the risk of a composite outcome of all-cause dementia or death, and each outcome. During the follow-up, 635 participants developed all-cause dementia and/or died, of which 379 participants developed dementia and 394 deaths occurred. The multivariable-adjusted HRs of the composite outcome decreased significantly with increasing serum SAM levels (P for trend = 0.01), while they increased significantly with higher serum SAH levels (P for trend = 0.03). Higher serum SAM/SAH ratio levels were significantly associated with a lower risk of the composite outcome (P for trend = 0.002), as well as with lower risk of each outcome. Our findings suggest that the balance of methionine metabolites may closely associate with the risk of dementia and death.


Asunto(s)
Demencia , S-Adenosilhomocisteína , Demencia/epidemiología , Humanos , Metionina , Modelos de Riesgos Proporcionales , S-Adenosilhomocisteína/metabolismo , S-Adenosilmetionina/metabolismo
19.
Exp Cell Res ; 316(20): 3342-50, 2010 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-20937271

RESUMEN

We aimed to clarify the transcription-regulation mechanisms of the mouse telomerase reverse transcriptase gene (mTERT). First, we searched for the promoter region required for transcriptional activation of mTERT and identified an enhancer cis-element (named mTERT-EE) located between -200 and -179bp of the mouse TERT gene (mTERT). EMSA results suggested that nuclear factor of activated T cells (NFAT) member proteins bind to mTERT-EE. We then identified NFAT5 as the factor binding to mTERT-EE and found that it activates the transcription of the mTERT core promoter. The results that siRNA directed against NFAT5 significantly reduced mTERT expression and mTERT core promoter activity and that the expressions of NFAT5 and mTERT were well correlated in various mouse tissues except liver suggest that NFAT5 dominantly and directly regulates mTERT expression. To clarify their functionality further, we investigated the effect of hypertonic stress, a known stimulus affecting the expression and transcriptional activity of NFAT5, on mTERT expression. The result indicated that hypertonic stress activates mTERT transcription via the activation and recruitment of NFAT5 to the mTERT promoter. These results provide useful information about the transcription-regulation mechanisms of mTERT.


Asunto(s)
Regulación de la Expresión Génica , Telomerasa/genética , Factores de Transcripción/metabolismo , Transcripción Genética , Estructuras Animales/metabolismo , Animales , Sitios de Unión/genética , Extractos Celulares/química , Núcleo Celular/química , Supervivencia Celular/genética , Ensayo de Cambio de Movilidad Electroforética , Elementos de Facilitación Genéticos/genética , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Expresión Génica/efectos de los fármacos , Expresión Génica/genética , Genes Reporteros/genética , Soluciones Hipertónicas/farmacología , Ratones , Ratones Endogámicos , Mutación/genética , Factores de Transcripción NFATC/metabolismo , Células 3T3 NIH , Regiones Promotoras Genéticas/genética , ARN Interferente Pequeño/genética , Estrés Fisiológico/genética , Factores de Transcripción/genética
20.
Biosci Biotechnol Biochem ; 75(5): 1016-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21597165

RESUMEN

In this study, we attempted to establish a novel method of screening anti-allergic lactic acid bacteria (LAB). We cloned the human histidine decarboxylase (HDC) promoter into the promoter-less pPhi-Yellow-RPL-dest1 vector and established KU812F cells transduced with this vector (pHDCp-Phi-Yellow/KU812F). After adding LAB to these cells, the change in fluorescence intensity was monitored by flow cytometry. After screening, we identified several LAB strains that downregulated HDC promoter activity. Functional analysis of these LAB strains indicated that two LAB strains inhibited histamine release from KU812F cells, indicating that this assay system can be used to screen for anti-allergic LAB in a high-throughput manner.


Asunto(s)
Citometría de Flujo/métodos , Hipersensibilidad/microbiología , Ácido Láctico/metabolismo , Lactobacillaceae/fisiología , Línea Celular , Regulación hacia Abajo , Histidina Descarboxilasa/genética , Histidina Descarboxilasa/metabolismo , Humanos , Hipersensibilidad/enzimología , Lactobacillaceae/metabolismo , Regiones Promotoras Genéticas/genética
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