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1.
Int Immunol ; 34(1): 21-33, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34648636

RESUMO

Plasmodium parasites that infect humans are highly polymorphic, and induce various infections ranging from an asymptomatic state to life-threatening diseases. However, how the differences between the parasites affect host immune responses during blood-stage infection remains largely unknown. We investigated the CD4+ T-cell immune responses in mice infected with P. berghei ANKA (PbA) or P. chabaudi chabaudi AS (Pcc) using PbT-II cells, which recognize a common epitope of these parasites. In the acute phase of infection, CD4+ T-cell responses in PbA-infected mice showed a lower involvement of Th1 cells and a lower proportion of Ly6Clo effector CD4+ T cells than those in Pcc-infected mice. Transcriptome analysis of PbT-II cells indicated that type I interferon (IFN)-regulated genes were expressed at higher levels in both Th1- and Tfh-type PbT-II cells from PbA-infected mice than those from Pcc-infected mice. Moreover, IFN-α levels were considerably higher in PbA-infected mice than in Pcc-infected mice. Inhibition of type I IFN signaling increased PbT-II and partially reversed the Th1 over Tfh bias of the PbT-II cells in both PbA- and Pcc-infected mice. In the memory phase, PbT-II cells in PbA-primed mice maintained higher numbers and exhibited a better recall response to the antigen. However, recall responses were not significantly different between the infection groups after re-challenge with PbA, suggesting the effect of the inflammatory environment by the infection. These observations suggest that the differences in Plasmodium-specific CD4+ T-cell responses between PbA- and Pcc-infected mice were associated with the difference in type I IFN production during the early phase of the infection.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Interferon Tipo I/biossíntese , Malária/imunologia , Plasmodium berghei/imunologia , Plasmodium chabaudi/imunologia , Animais , Células Cultivadas , Camundongos , Camundongos Transgênicos
2.
Int Immunol ; 33(8): 409-422, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-33914894

RESUMO

Upon activation, specific CD4+ T cells up-regulate the expression of CD11a and CD49d, surrogate markers of pathogen-specific CD4+ T cells. However, using T-cell receptor transgenic mice specific for a Plasmodium antigen, termed PbT-II, we found that activated CD4+ T cells develop not only to CD11ahiCD49dhi cells, but also to CD11ahiCD49dlo cells during acute Plasmodium infection. CD49dhi PbT-II cells, localized in the red pulp of spleens, expressed transcription factor T-bet and produced IFN-γ, indicating that they were type 1 helper T (Th1)-type cells. In contrast, CD49dlo PbT-II cells resided in the white pulp/marginal zones and were a heterogeneous population, with approximately half of them expressing CXCR5 and a third expressing Bcl-6, a master regulator of follicular helper T (Tfh) cells. In adoptive transfer experiments, both CD49dhi and CD49dlo PbT-II cells differentiated into CD49dhi Th1-type cells after stimulation with antigen-pulsed dendritic cells, while CD49dhi and CD49dlo phenotypes were generally maintained in mice infected with Plasmodium chabaudi. These results suggest that CD49d is expressed on Th1-type Plasmodium-specific CD4+ T cells, which are localized in the red pulp of the spleen, and can be used as a marker of antigen-specific Th1 CD4+ T cells, rather than that of all pathogen-specific CD4+ T cells.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Integrina alfa4/imunologia , Malária/imunologia , Plasmodium chabaudi/imunologia , Células T Auxiliares Foliculares/imunologia , Células Th1/imunologia , Transferência Adotiva/métodos , Animais , Células Cultivadas , Células Dendríticas/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-bcl-6/imunologia , Baço/imunologia , Linfócitos T Auxiliares-Indutores/imunologia
3.
J Clin Lab Anal ; 35(2): e23639, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33107085

RESUMO

BACKGROUND: The intra-individual reference range is generally narrower than the commonly used reference range. Consequently, close monitoring of changes in the laboratory test results of individuals based on the inter-individual reference range remains challenging. METHODS: We examined the determination of individual reference ranges using four indicators of nutritional conditions: transferrin (TRF), albumin (ALB), retinol-binding protein (RBP), and transthyretin (TTR). The subjects comprised 20 healthy individuals and blood samples were collected and tested five times at 2-week intervals. We used the measurement results for the four indicators and examined individual reference ranges using four methods, including calculation methods based on the reference change value and Bayesian inference. RESULTS: The resulting intra-individual reference ranges were narrower than the currently used inter-individual reference range for all measurements using four methods. Furthermore, the intra-individual coefficient of variation [CV (intra)] was smaller than the inter-individual coefficient of variation [CV (inter)] for TRF, RBP, and TTR for all 20 subjects. The means CV (intra) for the four indicators were also lower than the corresponding CV (inter). CONCLUSIONS: The intra-individual reference range can be used to validate the standard deviation and coefficient of variation for currently used indicators. Moreover, Bayesian methods are speculated to be the most versatile.


Assuntos
Análise Química do Sangue/métodos , Pré-Albumina/análise , Proteínas de Ligação ao Retinol/análise , Albumina Sérica Humana/análise , Transferrina/análise , Adulto , Teorema de Bayes , Variação Biológica Individual , Análise Química do Sangue/normas , Análise Química do Sangue/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Apoio Nutricional , Valores de Referência
4.
Int J Mol Sci ; 22(19)2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34638731

RESUMO

In recent years, brown adipose tissue (BAT), which has a high heat-producing capacity, has been confirmed to exist even in adults, and it has become a focal point for the prevention and the improvement of obesity and lifestyle-related diseases. However, the influences of obesity and physical activity (PA) on the fluid factors secreted from BAT (brown adipokines) are not well understood. In this study, therefore, we focused on brown adipokines and investigated the effects of obesity and PA. The abnormal expressions of gene fluid factors such as galectin-3 (Lgals3) and Lgals3 binding protein (Lgals3bp), whose proteins are secreted from HB2 brown adipocytes, were observed in the interscapular BAT of obese mice fed a high-fat diet for 4 months. PA attenuated the abnormalities in the expressions of these genes. Furthermore, although the gene expressions of factors related to brown adipocyte differentiation such as peroxisome proliferator-activated receptor gamma coactivator 1-α were also down-regulated in the BAT of the obese mice, PA suppressed the down-regulation of these factors. On the other hand, lipogenesis was increased more in HB2 cells overexpressing Lgals3 compared with that in control cells, and the overexpression of Lgals3bp decreased the mitochondrial mass. These results indicate that PA attenuates the obesity-induced dysregulated expression of brown adipokines and suggests that Lgals3 and Lgals3bp are involved in brown adipocyte differentiation.


Assuntos
Adipócitos Marrons/metabolismo , Adipocinas/biossíntese , Tecido Adiposo Marrom/metabolismo , Galectina 3/biossíntese , Regulação da Expressão Gênica , Obesidade/metabolismo , Condicionamento Físico Animal , Animais , Diferenciação Celular , Camundongos
5.
Int J Mol Sci ; 21(18)2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32967199

RESUMO

Exercise training is well known to enhance adipocyte lipolysis in response to hormone challenge. However, the existence of a relationship between the timing of exercise training and its effect on adipocyte lipolysis is unknown. To clarify this issue, Wistar rats were run on a treadmill for 9 weeks in either the early part (E-EX) or late part of the active phase (L-EX). L-EX rats exhibited greater isoproterenol-stimulated lipolysis expressed as fold induction over basal lipolysis, with greater protein expression levels of hormone-sensitive lipase (HSL) phosphorylated at Ser 660 compared to E-EX rats. Furthermore, we discovered that Brain and muscle Arnt-like (BMAL)1 protein can associate directly with several protein kinase A (PKA) regulatory units (RIα, RIß, and RIIß) of protein kinase, its anchoring protein (AKAP)150, and HSL, and that the association of BMAL1 with the regulatory subunits of PKA, AKAP150, and HSL was greater in L-EX than in E-EX rats. In contrast, comparison between E-EX and their counterpart sedentary control rats showed a greater co-immunoprecipitation only between BMAL1 and ATGL. Thus, both E-EX and L-EX showed an enhanced lipolytic response to isoproterenol, but the mechanisms underlying exercise training-enhanced lipolytic response to isoproterenol were different in each group.


Assuntos
Isoproterenol/farmacologia , Lipólise/efeitos dos fármacos , Condicionamento Físico Animal , Esterol Esterase/metabolismo , Proteínas de Ancoragem à Quinase A/metabolismo , Animais , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Masculino , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar
6.
Environ Health Prev Med ; 23(1): 40, 2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30131067

RESUMO

BACKGROUND: Heat shock protein 70 (HSP70) exhibits protective effects against ultraviolet (UV)-induced premature skin aging. A standardized extract of Asparagus officinalis stem (EAS) is produced as a novel and unique functional food that induces HSP70 cellular expression. To elucidate the anti-photoaging potencies of EAS, we examined its effects on HSP70 expression levels in UV-B-irradiated normal human dermal fibroblasts (NHDFs). METHODS: NHDFs were treated with 1 mg/mL of EAS or dextrin (vehicle control) prior to UV-B irradiation (20 mJ/cm2). After culturing NHDFs for different time periods, HSP70 mRNA and protein levels were analyzed using real-time polymerase chain reaction and western blotting, respectively. RESULTS: UV-B-irradiated NHDFs showed reduced HSP70 mRNA levels after 1-6 h of culture, which were recovered after 24 h of culture. Treatment with EAS alone for 24 h increased HSP70 mRNA levels in the NHDFs, but the increase was not reflected in its protein levels. On the other hand, pretreatment with EAS abolished the UV-B irradiation-induced reduction in HSP70 expression at both mRNA and protein levels. These results suggest that EAS is capable to preserve HSP70 quantity in UV-B-irradiated NHDFs. CONCLUSIONS: EAS exhibits anti-photoaging potencies by preventing the reduction in HSP70 expression in UV-irradiated dermal fibroblasts.


Assuntos
Asparagus , Fibroblastos/efeitos dos fármacos , Fibroblastos/efeitos da radiação , Proteínas de Choque Térmico HSP70/biossíntese , Extratos Vegetais/farmacologia , Raios Ultravioleta/efeitos adversos , Células Cultivadas , Feminino , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Envelhecimento da Pele/efeitos dos fármacos , Envelhecimento da Pele/efeitos da radiação , Telômero/metabolismo
7.
Mediators Inflamm ; 2017: 9290416, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28133422

RESUMO

Moderate-intensity regular exercise improves proinflammatory responses of lipopolysaccharide- (LPS-) stimulated macrophages. However, intracellular events that mediate the beneficial effects of exercise were unclear. This study aimed to clarify the mechanism by which regular voluntary exercise (VE) improves proinflammatory cytokine production by macrophages challenged with LPS. Peritoneal macrophages from VE mice secreted considerably higher amounts of interleukin- (IL-) 1ß and IL-18 than did cells from sedentary control (SC) mice in the presence and absence of LPS, although tumor necrosis factor-α and IL-10 secretion were comparable between both groups. The mRNA levels of these cytokines increased significantly in response to LPS; similar levels were noted in macrophages from both SC and VE mice. Moreover, LPS evoked similar levels of degradation of inhibitor of κB (IκB) α and phosphorylation of IκB kinase ß, c-Jun N-terminal kinase, and p38 in macrophages from SC and VE mice. These results indicate that the increased IL-1ß and IL-18 secretion in VE mice are regulated posttranscriptionally. On the other hand, macrophages from VE mice showed higher amounts of caspase-1 protein than did cells from SC mice. These results suggest that regular VE potentiates IL-1ß and IL-18 secretion in LPS-challenged macrophages by increasing caspase-1 levels.


Assuntos
Caspase 1/metabolismo , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Animais , Células Cultivadas , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Condicionamento Físico Animal , Serpinas/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Virais/farmacologia
8.
Crit Rev Immunol ; 35(4): 261-75, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26757391

RESUMO

Circadian rhythms have long been known to regulate numerous physiological processes that vary across the diurnal cycle. The circadian clock system also controls various parameters of the immune system and its biological defense functions, allowing an organism to anticipate daily changes in activity and feeding and the associated risk of infection. Inflammation is an immune response triggered in living organisms in response to external stimuli. The risk of sepsis, an excessive inflammatory response, has been shown to have a diurnal variation. On the other hand, inflammatory responses are emerging to be induced by endogenous factors. Recent studies have suggested that chronic inflammation causes chronic diseases including rheumatoid arthritis, allergies, and aging-related diseases and that proteins encoded by clock genes affect the development of such chronic inflammatory diseases or increase the severity of their symptoms. Therefore, detailed understanding of circadian rhythm effects on inflammatory responses is expected to lead to new strategies for prevention or treatment of inflammatory diseases.


Assuntos
Doenças Autoimunes/fisiopatologia , Ritmo Circadiano/imunologia , Hipersensibilidade/fisiopatologia , Sistema Imunitário , Inflamação/imunologia , Animais , Humanos , Imunidade
9.
J Immunol ; 192(1): 407-17, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24307731

RESUMO

Disruption of the circadian rhythm is a contributory factor to clinical and pathophysiological conditions, including cancer, the metabolic syndrome, and inflammation. Chronic and systemic inflammation are a potential trigger of type 2 diabetes and cardiovascular disease and are caused by the infiltration of large numbers of inflammatory macrophages into tissue. Although recent studies identified the circadian clock gene Rev-erbα, a member of the orphan nuclear receptors, as a key mediator between clockwork and inflammation, the molecular mechanism remains unknown. In this study, we demonstrate that Rev-erbα modulates the inflammatory function of macrophages through the direct regulation of Ccl2 expression. Clinical conditions associated with chronic and systemic inflammation, such as aging or obesity, dampened Rev-erbα gene expression in peritoneal macrophages from C57BL/6J mice. Rev-erbα agonists or overexpression of Rev-erbα in the murine macrophage cell line RAW264 suppressed the induction of Ccl2 following an LPS endotoxin challenge. We discovered that Rev-erbα represses Ccl2 expression directly through a Rev-erbα-binding motif in the Ccl2 promoter region. Rev-erbα also suppressed CCL2-activated signals, ERK and p38, which was recovered by the addition of exogenous CCL2. Further, Rev-erbα impaired cell adhesion and migration, which are inflammatory responses activated through the ERK- and p38-signaling pathways, respectively. Peritoneal macrophages from mice lacking Rev-erbα display increases in Ccl2 expression. These data suggest that Rev-erbα regulates the inflammatory infiltration of macrophages through the suppression of Ccl2 expression. Therefore, Rev-erbα may be a key link between aging- or obesity-associated impairment of clockwork and inflammation.


Assuntos
Quimiocina CCL2/genética , Relógios Circadianos/genética , Regulação da Expressão Gênica , Inflamação/genética , Inflamação/imunologia , Macrófagos/metabolismo , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/genética , Fatores Etários , Animais , Adesão Celular/genética , Linhagem Celular , Movimento Celular/genética , Movimento Celular/imunologia , Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Glicina/análogos & derivados , Glicina/farmacologia , Integrina beta1/metabolismo , Lipopolissacarídeos/imunologia , Macrófagos/imunologia , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Knockout , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/agonistas , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Obesidade/genética , Obesidade/imunologia , Fosforilação , Regiões Promotoras Genéticas , Ligação Proteica , Elementos de Resposta , Tiofenos/farmacologia , Ativação Transcricional , Molécula 1 de Adesão de Célula Vascular/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
J Cell Physiol ; 230(1): 199-209, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24958127

RESUMO

Ghrelin is a physiological-active peptide with growth hormone-releasing activity, orexigenic activity, etc. In addition, the recent study has also suggested that ghrelin possesses the pathophysiological abilities related with type 2 diabetes. However, the ghrelin-direct-effects implicated in type 2 diabetes on peripheral tissues have been still unclear, whereas its actions on the central nervous system (CNS) appear to induce the development of diabetes. Thus, to assess its peripheral effects correlated with diabetes, we investigated the regulatory mechanisms about adipokines, which play a central role in inducing peripheral insulin resistance, secreted from mature 3T3-L1 adipocytes stimulated with ghrelin in vitro . The stimulation with 50 nmol/L ghrelin for 24 h resulted in the significant 1.9-fold increase on vascular endothelial growth factor-120 (VEGF(120)) releases (p < 0.01) and the 1.7-fold on monocyte chemoattractant protein-1 (MCP-1) (p < 0.01) from 3T3-L1 adipocytes, respectively, while ghrelin failed to enhance tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), IL-6, IL-10 and adiponectin secretions. In addition, Akt phosphorylation on Ser473 and c-Jun NH2 -terminal protein kinase (JNK) phosphorylation on Thr183/Tyr185 were markedly enhanced 1.4-fold (p < 0.01) and 1.6-fold (p < 0.01) in the ghrelin-stimulated adipocytes, respectively. Furthermore, the treatment with LY294002 (50 µmol/L) and Wortmannin (10nmol/L), inhibitors of phosphatidylinositol 3-kinase (PI3K), significantly decreased the amplified VEGF(120) secretion by 29% (p < 0.01) and 28% (p < 0.01) relative to the cells stimulated by ghrelin alone, respectively, whereas these inhibitors had no effects on increased MCP-1 release. On the other hand, JNK inhibitor SP600125 (10 µmol/L) clearly reduced the increased MCP-1, but not VEGF(120), release by 35% relative to the only ghrelin-stimulated cells (p < 0.01). In conclusion, ghrelin can enhance the secretions of proinflammatory adipokines, VEGF(120) and MCP-1, but fails to affect IL-10 and adiponectin which are considered to be anti-inflammatory adipokines. Moreover, this augmented VEGF(120) release is invited through the activation of PI3K pathways and the MCP-1 is through JNK pathways. Consequently, our results strongly suggest that ghrelin can induce the development of diabetes via its direct-action in peripheral tissues as well as via in CNS.


Assuntos
Adipócitos/efeitos dos fármacos , Quimiocina CCL2/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Grelina/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Células 3T3 , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP/biossíntese , Adipócitos/metabolismo , Adiponectina/biossíntese , Androstadienos/farmacologia , Animais , Antracenos/farmacologia , Linhagem Celular , Cromonas/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Interleucina-10/biossíntese , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos , Morfolinas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Wortmanina
11.
Biochem Biophys Res Commun ; 464(1): 348-53, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26141235

RESUMO

It is widely accepted that lipolysis in adipocytes are regulated through the enzymatic activation of both hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL) via their phosphorylation events. Accumulated evidence shows that habitual exercise training (HE) enhances the lipolytic response in primary white adipocytes with changes in the subcellular localization of lipolytic molecules. However, no study has focused on the effect that HE exerts on the phosphorylation of both HSL and ATGL in primary white adipocytes. It has been shown that the translocation of HSL from the cytosol to lipid droplet surfaces requires its phosphorylation at Ser-563. In primary white adipocytes obtained from HE rats, the level of HSL and ATGL proteins was higher than that in primary white adipocytes obtained from sedentary control (SC) rats. In HE rats, the level of phosphorylated ATGL and HSL was also significantly elevated compared with that in SC rats. These differences were confirmed by Phos-tag SDS-PAGE, a technique used to measure the amount of total phosphorylated proteins. Our results suggest that HE can consistently increase the activity of both lipases, thereby enhancing the lipolysis in white fat cells. Thus, HE helps in the prevention and treatment of obesity-related diseases by enhancing the lipolytic capacity.


Assuntos
Adipócitos Brancos/enzimologia , Lipase/metabolismo , Obesidade/prevenção & controle , Condicionamento Físico Animal , Esterol Esterase/metabolismo , Adipócitos Brancos/citologia , Animais , Ativação Enzimática , Regulação da Expressão Gênica , Lipase/genética , Gotículas Lipídicas/metabolismo , Lipólise/genética , Masculino , Fosforilação , Cultura Primária de Células , Transporte Proteico , Ratos , Ratos Wistar , Esterol Esterase/genética
12.
J Pineal Res ; 59(2): 267-75, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26123001

RESUMO

Melatonin is synthesized in the pineal gland, but elicits a wide range of physiological responses in peripheral target tissues. Recent advances suggest that melatonin controls adiposity, resulting in changes in body weight. The aim of this study was to investigate the effect of melatonin on adipogenesis and mitochondrial biogenesis in 3T3-L1 mouse embryo fibroblasts. Melatonin significantly increased the expression of peroxisome proliferator-activated receptor-γ (PPAR-γ), a master regulator of adipogenesis, and promoted differentiation into adipocytes. Melatonin-treated cells also formed smaller lipid droplets and abundantly expressed several molecules associated with lipolysis, including adipose triglyceride lipase, perilipin, and comparative gene identification-58. Moreover, the hormone promoted biogenesis of mitochondria, as indicated by fluorescent staining, elevated the citrate synthase activity, and upregulated the expression of PPAR-γ coactivator 1 α, nuclear respiratory factor-1, and transcription factor A. The expression of uncoupling protein 1 was also observable both at mRNA and at protein level in melatonin-treated cells. Finally, adiponectin secretion and the expression of adiponectin receptors were enhanced. These results suggest that melatonin promotes adipogenesis, lipolysis, mitochondrial biogenesis, and adiponectin secretion. Thus, melatonin has potential as an anti-obesity agent that may reverse obesity-related disorders.


Assuntos
Adipogenia/efeitos dos fármacos , Melatonina/farmacologia , Mitocôndrias/metabolismo , Células 3T3-L1 , Adiponectina/metabolismo , Animais , Lipólise/efeitos dos fármacos , Camundongos , PPAR gama/metabolismo
13.
J Immunol ; 191(7): 3799-809, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23997226

RESUMO

Naturally occurring regulatory T cells (nTregs), important for immune regulation and the maintenance of self-tolerance, develop in the thymus. The Hirosaki hairless rat (HHR), derived from the Sprague-Dawley rat (SDR), was shown to have decreased peripheral lymphocyte number, small thymus, and leukocyte infiltration in its dermis. In the HHR thymus, the medulla was underdeveloped and nTreg number was decreased. Array comparative genome hybridization revealed the deletion of an NK cell lectin-like receptor gene, Ly49s3, detecting MHC class I molecules on target cells, in the chromosome 4q42 region in HHRs. The gene was expressed in thymic conventional dendritic cells (cDCs) in SDRs, but not in HHRs. When CD4-single-positive or CD4(+)CD8(-)CD25(-) thymocytes were cultured with thymic cDCs, the expression of nTreg marker genes was lower when these cells were from HHRs than from SDRs, suggesting that HHR cDCs are deficient in the ability to induce and maintain nTreg differentiation. Expression of the genes was recovered when Ly49s3 was expressed on HHR thymic cDCs. Expression levels of MHC class II genes, presumably from cDCs, were parallel to those of nTreg marker genes in mixed-cell cultures. However, in the presence of an anti-MHC class I Ab, blocking interaction between Ly49s3 and MHC class I molecules, the expression of the former genes was upregulated, whereas the latter was downregulated. These results suggest that Ly49s3 contributes to nTreg regulation along with MHC class II molecules, whose effects alone are insufficient, and loss of Ly49s3 from thymic cDCs is the reason for the nTreg deficiency in HHRs.


Assuntos
Diferenciação Celular/genética , Células Dendríticas/metabolismo , Subfamília A de Receptores Semelhantes a Lectina de Células NK/genética , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/metabolismo , Timo/metabolismo , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular/imunologia , Células Dendríticas/imunologia , Expressão Gênica , Antígenos de Histocompatibilidade Classe II/imunologia , Contagem de Linfócitos , Masculino , Ratos , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/imunologia , Timo/imunologia , Timo/patologia
14.
ScientificWorldJournal ; 2014: 685854, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25401152

RESUMO

It is now evident that many nuclear hormone receptors can modulate target gene expression. REV-ERBα, one of the nuclear hormone receptors with the capacity to alter clock function, is critically involved in lipid metabolism, adipogenesis, and the inflammatory response. Recent studies suggest that REV-ERBα plays a key role in the mediation between clockwork and inflammation. The purpose of the current study was to investigate the role of REV-ERBα in the regulation of interleukin-6 (il6) gene expression in murine macrophages. REV-ERBα agonists, or overexpression of rev-erb α in the murine macrophage cell line RAW264 cells, suppressed the induction of il6 mRNA following a lipopolysaccharide (LPS) endotoxin challenge. Also, rev-erb α overexpression decreased LPS-stimulated nuclear factor κB (NFκB) activation in RAW264 cells. We showed that REV-ERBα represses il6 expression not only indirectly through an NFκB binding motif but also directly through a REV-ERBα binding motif in the murine il6 promoter region. Furthermore, peritoneal macrophages from mice lacking rev-erb α increased il6 mRNA expression. These data suggest that REV-ERBα regulates the inflammatory response of macrophages through the suppression of il6 expression. REV-ERBα may therefore be identified as a potent anti-inflammatory receptor and be a therapeutic target receptor of inflammatory diseases.


Assuntos
Regulação da Expressão Gênica , Interleucina-6/antagonistas & inibidores , Interleucina-6/biossíntese , Macrófagos Peritoneais/metabolismo , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/metabolismo , Animais , Linhagem Celular , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Regiões Promotoras Genéticas/fisiologia , Ligação Proteica/fisiologia
15.
Br J Nutr ; 110(9): 1549-58, 2013 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-23537529

RESUMO

Recently, the ability of polyphenols to reduce the risk of dementia and Alzheimer's disease (AD) has attracted a great deal of interest. In the present study, we investigated the attenuating effects of oligomerised lychee fruit-derived polyphenol (OLFP, also called Oligonol) on early cognitive impairment. Male senescence-accelerated mouse prone 8 (SAMP8) mice (4 months old) were given OLFP (100 mg/kg per d) for 2 months, and then conditioned fear memory testing was conducted. Contextual fear memory, which is considered hippocampus-dependent memory, was significantly impaired in SAMP8 mice compared with non-senescence-accelerated mice. OLFP attenuated cognitive impairment in SAMP8 mice. Moreover, the results of real-time PCR analysis that followed DNA array analysis in the hippocampus revealed that, compared with SAMP8 mice, the mRNA expression of Wolfram syndrome 1 (Wfs1) was significantly higher in SAMP8 mice administered with OLFP. Wfs1 reportedly helps to protect against endoplasmic reticulum (ER) stress, which is thought to be one of the causes for AD. The expression of Wfs1 was significantly up-regulated in NG108-15 neuronal cells by the treatment with OLFP, and the up-regulation was inhibited by the treatment of the cells with a c-Jun N-terminal kinase-specific inhibitor rather than with an extracellular signal-regulated kinase inhibitor. Moreover, OLFP significantly attenuated the tunicamycin-induced expression of the ER stress marker BiP (immunoglobulin heavy chain-binding protein) in the cells. These results suggest that OLFP has an attenuating effect on early cognitive impairment in SAMP8 mice, and diminishes ER stress in neuronal cells.


Assuntos
Catequina/análogos & derivados , Transtornos Cognitivos/tratamento farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Litchi/química , Transtornos da Memória/tratamento farmacológico , Fenóis/uso terapêutico , Fitoterapia , Polifenóis/uso terapêutico , Envelhecimento , Doença de Alzheimer/metabolismo , Doença de Alzheimer/prevenção & controle , Animais , Catequina/farmacologia , Catequina/uso terapêutico , Transtornos Cognitivos/metabolismo , Retículo Endoplasmático/efeitos dos fármacos , Chaperona BiP do Retículo Endoplasmático , Frutas/química , Proteínas de Choque Térmico/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Memória/efeitos dos fármacos , Transtornos da Memória/metabolismo , Camundongos , Camundongos Endogâmicos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Polifenóis/farmacologia , RNA Mensageiro/metabolismo
16.
Nanoscale ; 15(14): 6521-6535, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36938953

RESUMO

The photocatalytic water splitting process to produce H2 is an attractive approach to meet energy demands while achieving carbon emission reduction targets. However, none of the current photocatalytic devices meets the criteria for practical sustainable H2 production due to their insufficient efficiency and the resulting high H2 cost. Economic viability may be achieved by simultaneously producing more valuable products than O2 or integrating with reforming processes of real waste streams, such as plastic and food waste. Research over the past decade has begun to investigate the possibility of replacing water oxidation with more kinetically and thermodynamically facile oxidation reactions. We summarize how various alternative photo-oxidation reactions can be combined with proton reduction in photocatalysis to achieve chemical valorization with concurrent H2 production. By examining the current advantages and challenges of these oxidation reactions, we intend to demonstrate that these technologies would contribute to providing H2 energy, while also producing high-value chemicals for a sustainable chemical industry and eliminating waste.

17.
Mod Rheumatol Case Rep ; 7(2): 416-421, 2023 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-36715286

RESUMO

We report a case of anti-transcriptional intermediary factor 1γ antibody-positive dermatomyositis following nivolumab treatment. The patient was successfully treated with pulse steroid therapy and high-dose intravenous immunoglobulin, followed by oral glucocorticoid treatment. Immune checkpoint inhibitors, such as nivolumab, may induce not only myositis as an immune-related adverse event but also dermatomyositides as a paraneoplastic syndrome by distracting immune tolerance. Differentiating between pathologies is warranted if patients develop myositis after immune checkpoint inhibitor administration.


Assuntos
Dermatomiosite , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Miosite , Humanos , Nivolumabe/efeitos adversos , Dermatomiosite/complicações , Dermatomiosite/diagnóstico , Dermatomiosite/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/induzido quimicamente , Carcinoma de Células Escamosas do Esôfago/complicações , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Miosite/complicações , Neoplasias Esofágicas/complicações , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/tratamento farmacológico
18.
Biosci Biotechnol Biochem ; 76(12): 2230-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23221699

RESUMO

L-Theanine has favorable physiological effects in terms of human health, but the mechanisms that transport it to its target organs or cells are not completely defined. To identify the major transport mechanisms of L-theanine, we screened for candidate transporters of L-3H-theanine in several mammal cell lines that intrinsically express multiple transporters with various specificities. All of the cells tested, T24, HepG2, COS1, 293A, Neuro2a, and HuH7, absorbed L-3H-theanine. Uptake was significantly inhibited by the addition of L-leucine and by a specific inhibitor of the system L transport system, 2-aminobicyclo-(2,2,1)-heptane-2-carboxylic acid (BCH). L-3H-Theanine uptake occurred mostly independently of Na+. These results indicate that L-theanine was taken up via a system L like transport system in all of the cells tested. Additionally, in experiments using cells stably expressing two system L isoforms, LAT1 and LAT2, we found that the two isoforms mediated L-theanine transport to similar extents. Taken together, our results indicate that L-theanine is transported mostly via the system L transport pathway and its isoforms.


Assuntos
Sistemas de Transporte de Aminoácidos Básicos/metabolismo , Glutamatos/metabolismo , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Animais , Transporte Biológico , Proteínas de Transporte/metabolismo , Linhagem Celular , Humanos , Cinética , Camundongos , Sódio/metabolismo
19.
Environ Health Prev Med ; 17(5): 348-56, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22362099

RESUMO

Recent increases in the number of obese individuals and individuals suffering from lifestyle-related diseases, such as type 2 diabetes, that accompany obesity have become a serious social problem. White adipose tissue (WAT) is more than a mere organ for storage of energy; it is also a highly active metabolic and endocrine organ that secretes physiologically active substances collectively known as adipokines, including tumor necrosis factor-α and adiponectin. Dysregulated expression of adipokines in WAT that is hypertrophied by obesity has been closely associated with the phenomenon of insulin resistance. Therefore, WAT is currently considered to be one of the tissues that promote lifestyle-related diseases. Reduction of excess WAT that results from obesity is seen as an important strategy in preventing and improving lifestyle-related diseases. This review shows that exercise training as well as intake of supplements, such as polyphenols, is one strategy for this, because this regimen can result in reduction of WAT mass, which affects the expression and secretory response of adipokines.


Assuntos
Adiponectina/metabolismo , Tecido Adiposo Branco/metabolismo , Suplementos Nutricionais , Exercício Físico , Estilo de Vida , Obesidade/prevenção & controle , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/imunologia , Quimiocina CCL2/metabolismo , Humanos , Obesidade/imunologia , Obesidade/metabolismo , Obesidade/terapia , Polifenóis/administração & dosagem , Fator de Necrose Tumoral alfa/metabolismo
20.
NPJ Digit Med ; 5(1): 43, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35414651

RESUMO

Alzheimer's disease is a neurodegenerative disease that imposes a substantial financial burden on society. A number of machine learning studies have been conducted to predict the speed of its progression, which varies widely among different individuals, for recruiting fast progressors in future clinical trials. However, because the data in this field are very limited, two problems have yet to be solved: the first is that models built on limited data tend to induce overfitting and have low generalizability, and the second is that no cross-cohort evaluations have been done. Here, to suppress the overfitting caused by limited data, we propose a hybrid machine learning framework consisting of multiple convolutional neural networks that automatically extract image features from the point of view of brain segments, which are relevant to cognitive decline according to clinical findings, and a linear support vector classifier that uses extracted image features together with non-image information to make robust final predictions. The experimental results indicate that our model achieves superior performance (accuracy: 0.88, area under the curve [AUC]: 0.95) compared with other state-of-the-art methods. Moreover, our framework demonstrates high generalizability as a result of evaluations using a completely different cohort dataset (accuracy: 0.84, AUC: 0.91) collected from a different population than that used for training.

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