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1.
Phys Chem Chem Phys ; 26(7): 6180-6188, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38300128

RESUMO

The application of liquid crystal technology typically relies on the precise control of molecular orientation at a surface or interface. This control can be achieved through a combination of morphological and chemical methods. Consequently, variations in constrained boundary flexibility can result in a diverse range of phase behaviors. In this study, we delve into the self-assembly of liquid crystals within elastic spatial confinement by using the Gay-Berne model with the aid of molecular dynamics simulations. Our findings reveal that a spherical elastic shell promotes a more regular and orderly alignment of liquid crystals compared to a hard shell. Moreover, during the cooling process, the hard-shell confined system undergoes an isotropic-smectic phase transition. In contrast, the phase behavior within the spherical elastic shell closely mirrors the isotropic-nematic-smectic phase transition observed in bulk systems. This indicates that the orientational arrangement of liquid crystals and the deformations induced by a flexible interface engage in a competitive interplay during the self-assembly process. Importantly, we found that phase behavior could be manipulated by altering the flexibility of the confined boundaries. This insight offers a fresh perspective for the design of innovative materials, particularly in the realm of liquid crystal/polymer composites.

2.
Eur J Clin Invest ; 51(8): e13547, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33782973

RESUMO

BACKGROUND: Our previous studies showed that vitamin D receptor (VDR) depletion promotes lipopolysaccharide (LPS)-induced acute kidney injury (AKI) in mice, and renal VDR is down-regulated in AKI, but the mechanism of VDR down-regulation is unclear. METHODS: Nutritional vitamin D deficiency was induced by feeding mice a vitamin D-deficient (VD-D) diet. Mice were injected intraperitoneally with LPS (20 mg/kg) to establish LPS-induced AKI. Levels of VDR and miR-122 were measured both in vivo and in vitro. The associations between VDR and miR-122 were analysed by dual-luciferase reporter assays. RESULTS: Compared with vitamin D-sufficient (VD-S) mice, VD-D mice developed more severe renal injury following LPS challenge. LPS induced a dramatic decrease in VDR expression and marked induction of miR-122 both in vivo and in vitro. Furthermore, miR-122 hairpin inhibitor alleviated LPS-induced VDR down-regulation whereas miR-122 mimic directly suppressed VDR expression in HK-2 cells. In luciferase reporter assays, miR-122 mimic was able to suppress luciferase activity in 293T cells co-transfected with a luciferase reporter that contains a putative miR-122 target site from 3'UTR of the VDR transcript, but not when this site was mutated. Moreover, miR-122 mimic significantly blocked paricalcitol-induced luciferase activity in 293T cells co-transfected with a VDRE-driven luciferase reporter, whereas miR-122 hairpin inhibitor enhanced paricalcitol's activity to suppress PUMA and caspase 3 activation induced by LPS in HK-2 cells. CONCLUSIONS: Collectively, these studies provide evidence that miR-122 directly targets VDR in renal tubular cells, which strongly suggest that miR-122 up-regulation in the kidney under LPS challenge contributes to kidney injury by down-regulating VDR expression.


Assuntos
Injúria Renal Aguda/genética , MicroRNAs/genética , Receptores de Calcitriol/genética , Deficiência de Vitamina D , Injúria Renal Aguda/induzido quimicamente , Animais , Apoptose , Regulação para Baixo , Células HEK293 , Humanos , Túbulos Renais/citologia , Lipopolissacarídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Vitamina D , Deficiência de Vitamina D/fisiopatologia
3.
Dig Dis Sci ; 66(11): 3813-3821, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33433800

RESUMO

BACKGROUND: The renin-angiotensin system (RAS) is activated in inflammatory bowel disease (IBD), and vitamin D deficiency aggravates the development of colitis, but the relationship between the local colonic RAS and vitamin D is unclear with regard to the pathogenesis of IBD. AIMS: To investigate whether vitamin D suppresses the local colonic RAS to prevent colonic mucosal inflammation in a mouse model of experimental colitis. METHODS: C57BL/6 mice fed vitamin D-deficient (VDD) diet for 8 weeks were induced to colitis by 2,4,6-trinitrobenzenesulfonic acid (TNBS), with mice fed vitamin D-sufficient (VDS) diet as controls. Colitis severity was assessed by histology, and pro-inflammatory cytokines, RAS components, and signaling pathways were quantified by real-time RT-PCR and Western blotting. RESULTS: C57BL/6 mice fed the VDD diet for 8 weeks exhibited significantly lower serum 25(OH)D3 concentrations compared to mice fed the VDS diet. When these VDD mice were induced to colitis by TNBS, they exhibited more severe colonic inflammation and developed more severe colitis compared to the VDS counterparts. VDD diet feeding resulted in higher production of mucosal pro-inflammatory cytokines, higher activation of the myosin light chain kinase-tight junction regulatory pathway, and greater increases in mucosal permeability. VDD diet feeding also enhanced colonic RAS activation. Treatment with angiotensin II receptor blocker losartan markedly alleviated colitis in TNBS-induced VDD mice. CONCLUSION: Vitamin D deficiency promotes colonic inflammation at least in part due to over activation of the local RAS in the colon.


Assuntos
Colite/induzido quimicamente , Colite/tratamento farmacológico , Sistema Renina-Angiotensina/fisiologia , Deficiência de Vitamina D/complicações , Vitamina D/administração & dosagem , Bloqueadores do Receptor Tipo 1 de Angiotensina II/metabolismo , Animais , Colite/metabolismo , Colite/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptor Tipo 1 de Angiotensina/metabolismo , Transdução de Sinais
4.
FASEB J ; 33(1): 1042-1050, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30074824

RESUMO

Vitamin D is known to play a protective role in inflammatory diseases. Although the suppressive effect of vitamin D/vitamin D receptor (VDR) signaling has been shown in the context of oral lichen planus (OLP), the molecular basis of its regulatory function remains poorly understood. Herein, we reported that miR-802 overexpression in OLP could aggravate apoptosis of oral keratinocytes by targeting B-cell lymphoma 2 mRNA. In addition, vitamin D/VDR signaling was able to suppress miR-802 expression in LPS-treated or activated CD4+ T cell-stimulated human oral keratinocytes by blocking NF-κB pathways, thereby inhibiting OLP apoptosis. Consistent with the results in vitro, we showed that miR-802 expression was enhanced in oral keratinocytes from VDR-/- mice, and an inverse correlation between VDR and miR-802 was found in human biopsy specimens of OLP. Collectively, our data suggest that vitamin D/VDR signaling suppresses oral keratinocyte apoptosis by targeting miR-802.-Zhao, B., Xu, N., Li, R., Yu, F., Zhang, F., Yang, F., Ge, X., Li, Y. C., Du, J. Vitamin D/VDR signaling suppresses microRNA-802-induced apoptosis of keratinocytes in oral lichen planus.


Assuntos
Apoptose/fisiologia , Queratinócitos/citologia , Líquen Plano Bucal/patologia , MicroRNAs/fisiologia , Receptores de Calcitriol/metabolismo , Transdução de Sinais , Vitamina D/metabolismo , Adulto , Animais , Linhagem Celular , Feminino , Humanos , Líquen Plano Bucal/genética , Líquen Plano Bucal/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptores de Calcitriol/genética , Regulação para Cima
5.
FASEB J ; 33(8): 9602-9615, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31150280

RESUMO

Obesity is a leading cause of chronic kidney disease (CKD), but how obesity promotes renal injury remains poorly understood. Here we showed that ATP-citrate lyase (ACL), an enzyme converting citrate to acetyl-CoA, is highly induced in the kidney of overweight or obese patients with CKD and ob/ob BTBR mice. ACL induction is associated with increased ectopic lipid accumulation (ELA), glomerulosclerosis, and albuminuria. Acetyl-CoA is the substrate for de novo lipogenesis as well as for histone acetylation. By raising acetyl-CoA concentration ACL promotes H3K9/14 and H3K27 hyperacetylation leading to up-regulation of several rate-limiting lipogenic enzymes and fibrogenic factors. On the other hand, the excess acetyl-CoA generated as a result of ACL induction provides the substrate for these lipogenic enzymes to drive de novo lipogenesis leading to ELA, a detrimental event toward renal injury. In mesangial cells, ACL is synergistically induced by high glucose, palmitate, and TNF-α via NF-κB and PKA pathways. Under these conditions, H3K9/14 and H3K27 hyperacetylation, as well as the induction of the lipogenic and fibrogenic proteins, are completely blocked in the presence of an ACL inhibitor. Collectively, these data suggest that ACL is an epigenetic regulator that promotes renal ELA and fibrogenesis leading to renal injury in obesity.-Chen, Y., Deb, D. K., Fu, X., Yi, B., Liang, Y., Du, J., He, L., Li, Y. C. ATP-citrate lyase is an epigenetic regulator to promote obesity-related kidney injury.


Assuntos
ATP Citrato (pro-S)-Liase/metabolismo , Epigênese Genética/genética , Obesidade/enzimologia , Obesidade/genética , ATP Citrato (pro-S)-Liase/genética , Acetilcoenzima A/metabolismo , Acetilação/efeitos dos fármacos , Animais , Western Blotting , Epigênese Genética/efeitos dos fármacos , Feminino , Glucose/farmacologia , Humanos , Imuno-Histoquímica , Masculino , Células Mesangiais/efeitos dos fármacos , Células Mesangiais/metabolismo , Camundongos , NF-kappa B/farmacologia , Ácido Palmítico/farmacologia
6.
Am J Physiol Renal Physiol ; 316(5): F1068-F1077, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30864841

RESUMO

Acute kidney injury (AKI) is a common complication of sepsis characterized by a rapid degradation of renal function. The effect of vitamin D on AKI remains poorly understood. Here, we showed that vitamin D receptor (VDR) activation protects against lipopolysaccharide (LPS)-induced AKI by blocking renal tubular epithelial cell apoptosis. Mice lacking VDR developed more severe AKI than wild-type (WT) control mice after LPS treatment, which was manifested by marked increases in body weight loss and accumulation of serum blood urea nitrogen and creatinine as well as the magnitude of apoptosis of tubular epithelial cells. In the renal cortex, LPS treatment led to more dramatic downregulation of Bcl-2, more robust induction of p53-upregulated modulator of apoptosis (PUMA) and miR-155, and more severe caspase-3 activation in VDR knockout mice compared with WT control mice. Conversely, paricalcitol pretreatment markedly prevented LPS-induced AKI. Paricalcitol ameliorated body weight loss, attenuated serum blood urea nitrogen and creatinine accumulation, blocked tubular cell apoptosis, prevented the suppression of Bcl-2, and reversed PUMA and miR-155 induction and caspase-3 activation in LPS-treated WT mice. In HK2 cells, LPS induced PUMA and miR-155 by activating NF-κB, whereas 1,25(OH)2D3 blocked PUMA and miR-155 induction by repressing NF-κB activation. Both PUMA and miR-155 target Bcl-2 to promote apoptosis; namely, PUMA inhibits Bcl-2 activity, whereas miR-155 promotes Bcl-2 mRNA degradation and inhibits Bcl-2 protein translation. Collectively, these data provide strong evidence that LPS induces tubular cell apoptosis via upregulating PUMA and miR-155, whereas vitamin D/VDR signaling protects against AKI by blocking NF-κB-mediated PUMA and miR-155 upregulation.


Assuntos
Injúria Renal Aguda/prevenção & controle , Apoptose/efeitos dos fármacos , Ergocalciferóis/farmacologia , Túbulos Renais Proximais/efeitos dos fármacos , Lipopolissacarídeos , Receptores de Calcitriol/agonistas , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Modelos Animais de Doenças , Humanos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Células RAW 264.7 , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Transdução de Sinais , Proteínas Supressoras de Tumor/metabolismo
7.
Am J Physiol Gastrointest Liver Physiol ; 317(4): G453-G462, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31411504

RESUMO

Diets high in animal fats are associated with increased risks of inflammatory bowel disease, but the mechanism remains unclear. In this study, we investigated the effect of high-fat diet (HFD) on the development of experimental colitis in mice. Relative to mice fed low-fat diet (LFD), HFD feeding for 4 wk increased the levels of triglyceride, cholesterol, and free fatty acids in the plasma as well as within the colonic mucosa. In an experimental colitis model induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS), mice on 4-wk HFD exhibited more severe colonic inflammation and developed more severe colitis compared with the LFD counterparts. HFD feeding resulted in higher production of mucosal pro-inflammatory cytokines, greater activation of the myosin light chain kinase (MLCK) tight junction regulatory pathway, and greater increases in mucosal barrier permeability in mice following TNBS induction. HFD feeding also induced gp91, an NADPH oxidase subunit, and promoted reactive oxygen species (ROS) production in both colonic epithelial cells and lamina propria cells. In HCT116 cell culture, palmitic acid or palmitic acid and TNF-α combination markedly increased ROS production and induced the MLCK pathway, and these effects were markedly diminished in the presence of a ROS scavenger. Taken together, these data suggest that HFD promotes colitis by aggravating mucosal oxidative stress, which rapidly drives mucosal inflammation and increases intestinal mucosal barrier permeability.NEW & NOTEWORTHY This study demonstrates high-fat diet feeding promotes colitis in a 2,4,6-trinitrobenzenesulfonic acid-induced experimental colitis model in mice. The underlying mechanism is that high-fat diet induces oxidative stress in the colonic mucosa, which increases colonic epithelial barrier permeability and drives colonic mucosal inflammation. These observations provide molecular evidence that diets high in saturated fats are detrimental to patients with inflammatory bowel diseases.


Assuntos
Colite/metabolismo , Colite/patologia , Colo/metabolismo , Dieta Hiperlipídica/efeitos adversos , Estresse Oxidativo , Animais , Linhagem Celular , Colesterol/sangue , Colesterol/metabolismo , Colite/induzido quimicamente , Colo/citologia , Citocinas/metabolismo , Células Epiteliais/metabolismo , Ácidos Graxos não Esterificados/sangue , Ácidos Graxos não Esterificados/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Quinase de Cadeia Leve de Miosina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Triglicerídeos/sangue , Triglicerídeos/metabolismo , Ácido Trinitrobenzenossulfônico
8.
Am J Physiol Gastrointest Liver Physiol ; 316(6): G774-G784, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30995068

RESUMO

Previous studies suggest that the renin-angiotensin system (RAS) is a pathogenic factor for colitis. The goal of this study was to elucidate the molecular mechanism whereby angiotensin II (ANG II) promotes colonic inflammation. We found that renin was highly induced in colonic biopsies from patients with ulcerative colitis or Crohn's disease, and colonic renin and ANG II levels were markedly increased in a 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis model, indicating that the colonic RAS is activated in colitis. Renin transgenic (RenTg) mice exhibited increased phosphorylation in Janus kinase-2 (JAK2) and signal transducer and activator of transcription1/3 (STAT1/3) within colonic mucosa at baseline and following TNBS induction, suggesting that ANG II promotes colonic inflammation via the JAK2/STAT1/3 pathway. Treatment with pan-JAK inhibitor tofacitinib blocked JAK2 and STAT1/3 phosphorylation, attenuated T helper (TH)1 and TH17 responses, alleviated colitis, and prevented death of RenTg mice in TNBS model. ANG II stimulated JAK2/STAT1/3 phosphorylation in both Jurkat T lymphocytes and HCT116 epithelial cells. In vitro polarization assays demonstrated that ANG II directly promoted TH17 polarization, but not TH1 polarization, via JAK2/STAT1/3. ANG II stimulation of transforming growth factor-ß1 (TGFß1), IL-6, myosin light chain kinase, and p53 upregulated modulator of apoptosis in HCT116 cells was also mediated by JAK2/STAT1/3. These observations suggest that ANG II promotes TH17 polarization directly as well as indirectly by inducing production of TH17-polarizing cytokines (e.g., TGFß1 and IL-6) from colonic epithelial cells, both via the JAK2/STAT pathway. Therefore, colonic RAS promotes colonic inflammation, at least in part, by stimulating TH17 activation. NEW & NOTEWORTHY This study demonstrates that the local renin-angiotensin system in the colon is activated in colitis development, which promotes mucosal T helper cell activation through the JAK2/STAT pathway. These observations provide molecular evidence that the renin-angiotensin system is a pathogenic factor for the development of inflammatory bowel diseases.


Assuntos
Colite Ulcerativa , Colo , Doença de Crohn , Ativação Linfocitária , Piperidinas/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Células Th17/fisiologia , Angiotensina II/metabolismo , Animais , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Colo/metabolismo , Colo/patologia , Doença de Crohn/metabolismo , Doença de Crohn/patologia , Humanos , Janus Quinase 2/metabolismo , Camundongos , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Sistema Renina-Angiotensina/fisiologia , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
9.
Org Biomol Chem ; 17(48): 10178-10187, 2019 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-31763665

RESUMO

A practical and efficient synthetic route to construct a variety of 3-amidated quinoxalin-2(1H)-ones was developed via transition-metal free direct oxidative amidation of quinoxalin-2(1H)-ones with amidates using Selectfluor reagent as a mild oxidant. This protocol features mild reaction conditions, operational simplicity, broad substrate scope, and good to excellent yields.

10.
Dig Dis Sci ; 64(7): 1938-1944, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30725290

RESUMO

BACKGROUND: Preclinical data demonstrate that activation of the renin-angiotensin system (RAS) contributes to mucosal inflammation, and RAS inhibition by angiotensin-converting-enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB) improves colitis in animal models. Less is known regarding the effects of RAS inhibition on clinical outcomes in inflammatory bowel disease (IBD) patients. AIM: Evaluate the impact of ACEI and ARB on clinical outcomes in IBD. METHODS: Rates of IBD-related hospitalizations, operations, and corticosteroid use were evaluated retrospectively in two groups. First, 111 IBD patients taking an ACEI or ARB were compared to nonusers matched 1:1 based on sex, age, diagnosis, disease location, and hypertension diagnosis. Second, outcomes in a cohort of 130 IBD patients were compared prior to and during ACEI/ARB exposure. RESULTS: Compared to matched controls, all IBD patients together with ACEI/ARB exposure had fewer hospitalizations (OR 0.26, p < 0.01), operations (OR 0.08, p = 0.02), and corticosteroid prescriptions (OR 0.5, p = 0.01). Comparing outcomes before and during ACEI/ARB use, there were no differences in hospitalizations, operations, or corticosteroid use for all IBD patients together, but patients with UC had increased hospitalizations (0.08 pre- vs. 0.16 during ACEI/ARB exposure, p = 0.03) and decreased corticosteroid use (0.24 pre-ACEI/ARB vs. 0.12 during ACEI/ARB exposure, p < 0.01) during ACEI/ARB use. CONCLUSIONS: IBD patients with ACEI/ARB exposure had fewer hospitalizations, operations, and corticosteroid use compared to matched controls. No differences in outcomes were observed in individuals on ACEI/ARB therapy when compared to a period of time prior to medication exposure.


Assuntos
Corticosteroides/uso terapêutico , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Colectomia , Colite Ulcerativa/terapia , Doença de Crohn/terapia , Admissão do Paciente , Sistema Renina-Angiotensina/efeitos dos fármacos , Corticosteroides/efeitos adversos , Idoso , Angiotensina II/metabolismo , Antagonistas de Receptores de Angiotensina/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Colectomia/efeitos adversos , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/metabolismo , Colite Ulcerativa/fisiopatologia , Doença de Crohn/diagnóstico , Doença de Crohn/metabolismo , Doença de Crohn/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transdução de Sinais , Fatores de Tempo , Resultado do Tratamento
11.
FASEB J ; 31(5): 2065-2075, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28148567

RESUMO

Hyperglycemia is a major pathogenic factor that promotes diabetic nephropathy, but the underlying mechanism remains incompletely understood. Here, we show that high glucose induced cAMP response element-binding protein (CREB)-binding protein (CBP)-mediated H3K9/14 hyperacetylation in approximately 5000 gene promoters in glomerular mesangial cells, including those of Tgfb1, Tgfb3, and Ctgf, the major profibrotic factors that are known to drive diabetic renal fibrogenesis. In these promoters, H3K9/14 hyperacetylation was closely associated with NF-κB or CREB motifs. Chromatin immunoprecipitation assays confirmed that hyperglycemia promoted phospho-p65 or phospho-CREB and CBP bindings and RNA polymerase II recruitment to these promoters in mesangial cells as well as in glomeruli that were purified from type I and type II diabetic mice. Under hyperglycemia, cAMP production and PKA activity were markedly increased as a result of glucose transporter 1-mediated glucose influx that drives glucose metabolism and ATP production, which led to increased phosphorylation of p65 and CREB. Inhibition of adenylyl cyclase or PKA activity blocked p65 and CREB phosphorylation, CBP recruitment, and histone acetylation in these promoters. Collectively, these data demonstrate that the cAMP-PKA pathway plays a key role in epigenetic regulation of key profibrotic factors in diabetes.-Deb, D. K., Bao, R., Li, Y. C. Critical role of the cAMP-PKA pathway in hyperglycemia-induced epigenetic activation of fibrogenic program in the kidney.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Epigênese Genética/genética , Hiperglicemia/metabolismo , Rim/metabolismo , Transdução de Sinais , Animais , Diabetes Mellitus Experimental/metabolismo , Camundongos , NF-kappa B/metabolismo , Proteínas Nucleares/metabolismo , Fosforilação , Regiões Promotoras Genéticas/genética
12.
Am J Physiol Renal Physiol ; 313(2): F423-F429, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28490526

RESUMO

The goal of this study was to address the role of ATP-citrate lyase (ACL), an enzyme that converts citrate to acetyl-CoA, in high glucose (HG)-induced histone acetylation and profibrotic gene expression. Our recent ChIP-Seq studies have demonstrated that HG induces genome-wide histone hyperacetylation in mesangial cells (MCs). Here, we showed that exposure of MCs to HG markedly increased histone acetylation at the H3K9/14 and H3K18 marks and induced the expression of potent profibrotic factors TGF-ß1, TGF-ß3, and connective tissue growth factor (CTGF). The induction of these profibrotic factors was further enhanced by histone deacetylase inhibitor but suppressed by histone acetyl-transferase inhibitor, confirming the importance of histone acetylation in this regulation. Interestingly, HG not only upregulated ACL expression but also promoted ACL nuclear translocation, evidenced by increased ACL concentration and activity in the nuclear extracts. Consistent with this observation, transfection of MCs with a plasmid-carrying green fluorescent protein (GFP)-ACL fusion protein led to GFP nuclear accumulation when cultured in HG condition. Silencing ACL with siRNAs alleviated HG-induced histone hyperacetylation, as well as upregulation of TGF-ß1, TGF-ß3, CTGF, and extracellular matrix (ECM) proteins fibronectin and collagen type IV, whereas ACL overexpression further enhanced HG induction of histone acetylation, as well as these profibrotic factors and ECM proteins. Collectively, these observations demonstrate that HG promotes ACL expression and translocation into the nucleus, where ACL converts citrate to acetyl-CoA to provide the substrate for histone acetylation, leading to upregulation of fibrogenic genes. Therefore, ACL plays a critical role in epigenetic regulation of diabetic renal fibrosis.


Assuntos
ATP Citrato (pro-S)-Liase/metabolismo , Nefropatias Diabéticas/enzimologia , Epigênese Genética/efeitos dos fármacos , Glucose/toxicidade , Histonas/genética , Células Mesangiais/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , ATP Citrato (pro-S)-Liase/genética , Acetilcoenzima A/metabolismo , Acetilação , Transporte Ativo do Núcleo Celular , Animais , Linhagem Celular Transformada , Ácido Cítrico/metabolismo , Colágeno Tipo IV/genética , Colágeno Tipo IV/metabolismo , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/patologia , Fibronectinas/genética , Fibronectinas/metabolismo , Fibrose , Células Mesangiais/enzimologia , Células Mesangiais/patologia , Camundongos , Interferência de RNA , Fatores de Tempo , Transfecção , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta3/genética , Fator de Crescimento Transformador beta3/metabolismo , Regulação para Cima
13.
Neurobiol Learn Mem ; 140: 52-61, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28213064

RESUMO

Schizophrenia (SCZ) is a neurodevelopmental psychiatric disorder, in which cognitive function becomes disrupted at early stages of the disease. Although the mechanisms underlying cognitive impairments remain unclear, N-methyl-D-aspartate receptors (NMDAR) hypofunctioning in the prefrontal cortex (PFC) has been implicated. Moreover, cognitive symptoms in SCZ are usually unresponsive to treatment with current antipsychotics and by onset, disruption of the dopamine system, not NMDAR hypofunctioning, dominates the symptoms. Therefore, treating cognitive deficits at an early stage is a realistic approach. In this study, we tested whether an early treatment targeting mGluR2 would be effective in ameliorating cognitive impairments in the methylazoxymethanol acetate (MAM) model of SCZ. We investigated the effects of an mGluR2 agonist/mGluR3 antagonist, LY395756 (LY39), on the NMDAR expression and function in juveniles, as well as cognitive deficits in adult rats after juvenile treatment. We found that gestational MAM exposure induced a significant decrease in total protein levels of the NMDAR subunit, NR2B, and a significant increase of pNR2BTyr1472 in the juvenile rat PFC. Treatment with LY39 in juvenile MAM-exposed rats effectively recovered the disrupted NMDAR expression. Furthermore, a subchronic LY39 treatment in juvenile MAM-exposed rats also alleviated the learning deficits and cognitive flexibility impairments when tested with a cross-maze based set-shifting task in adults. Therefore, our study demonstrates that targeting dysfunctional NMDARs with an mGluR2 agonist during the early stage of SCZ could be an effective strategy in preventing the development and progression in addition to ameliorating cognitive impairments of SCZ.


Assuntos
Aminoácidos Dicarboxílicos/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Cognição/efeitos dos fármacos , Aprendizagem/efeitos dos fármacos , Receptores de Glutamato Metabotrópico/agonistas , Esquizofrenia/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/metabolismo , Modelos Animais de Doenças , Acetato de Metilazoximetanol , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo , Esquizofrenia/induzido quimicamente
14.
Mycologia ; 109(3): 422-442, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28636496

RESUMO

Species of Pulveroboletus (Boletaceae, Boletales) in China are investigated on the basis of morphology and molecular phylogenetic analyses of DNA sequences from nuc rDNA region encompassing the internal transcribed spacers 1 and 2, along with the 5.8S rDNA (ITS) and nuc 28S rDNA D1-D2 domains (28S) and sequences from the translation elongation factor 1-α gene (TEF1). Nine species are recognized in the country, three of them are described as new: P. flaviscabrosus, P. rubroscabrosus, and P. subrufus, five of them are previous described taxa: P. brunneopunctatus, P. brunneoscabrosus, P. macrosporus, P. reticulopileus, and P. sinensis, the remaining one is tentatively named P. cf. ridleyi, which will be further studied in the future. A key to the Chinese taxa of the genus is provided. Unexpectedly, the current study did not identify disjunct populations of Pulveroboletus species in East Asia and North/Central America.


Assuntos
Basidiomycota/classificação , Basidiomycota/isolamento & purificação , Basidiomycota/citologia , Basidiomycota/genética , China , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Microscopia , Fator 1 de Elongação de Peptídeos/genética , Filogenia , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA
15.
Crit Rev Clin Lab Sci ; 53(2): 132-45, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26479950

RESUMO

The discovery of vitamin D receptor (VDR) expression in immune cells has opened up a new area of research into immunoregulation by vitamin D, a niche that is distinct from its classical role in skeletal health. Today, about three decades since this discovery, numerous cellular and molecular targets of vitamin D in the immune system have been delineated. Moreover, strong clinical associations between vitamin D status and the incidence/severity of many immune-regulated disorders (e.g. infectious diseases, cancers and autoimmunity) have prompted the idea of using vitamin D supplementation to manipulate disease outcome. While much is known about the effects of vitamin D on innate immune responses and helper T (T(H)) cell immunity, there has been relatively limited progress on the frontier of cytotoxic T lymphocyte (CTL) immunity--an arm of host cellular adaptive immunity that is crucial for the control of such intracellular pathogens as human immunodeficiency virus (HIV), tuberculosis (TB), malaria, and hepatitis C virus (HCV). In this review, we discuss the strong historical and clinical link between vitamin D and infectious diseases that involves cytotoxic T lymphocyte (CTL) immunity, present our current understanding as well as critical knowledge gaps in the realm of vitamin D regulation of host CTL responses, and highlight potential regulatory connections between vitamin D and effector and memory CD8 T cell differentiation events during infections.


Assuntos
Doenças Transmissíveis/imunologia , Imunidade , Neoplasias/imunologia , Linfócitos T Citotóxicos/imunologia , Vitamina D/metabolismo , Animais , Suplementos Nutricionais , Humanos , Neoplasias/patologia
16.
Mycologia ; 108(2): 363-80, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26740536

RESUMO

Species of the genus Retiboletus (Boletaceae, Boletales) in China are investigated based on morphology and phylogenetic analyses of DNA sequences from nuc rDNA internal transcribed spacer (ITS) and partial 28S regions and sequences from the translation elongation factor 1-a gene (tef1a). Six lineages are recovered among the collections studied. Five of these are documented and presented in the present paper, including three new species and two new combinations. The remaining species is not described due to the paucity of material. The specimens from China identified as "R. ornatipes" or "R. retipes" are in fact R. sinensis or R. kauffmanii, those labeled "R. griseus" are either R. fuscus or R. pseudogriseus A key to all known taxa of the genus is provided. Phylogenetic relationships of taxa within Retiboletus are partially resolved. A preliminary biogeographical analysis shows that allied species of Retiboletus between eastern Asia and North/Central America are common but there are no Retiboletus species common to both continents. Species of Retiboletus in Japan and southern China are conspecific or closely related.


Assuntos
Basidiomycota/classificação , Basidiomycota/citologia , Basidiomycota/genética , Basidiomycota/fisiologia , China , Carpóforos/classificação , Carpóforos/fisiologia , Filogenia , Especificidade da Espécie
17.
Phytother Res ; 30(6): 1016-20, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26990224

RESUMO

Androgenetic alopecia (AGA) affects approximately 70% of men and 40% of women in an age-dependent manner and is partially mediated by androgen hormones. Benign prostatic hyperplasia (BPH) similarly affects 50% of the male population, rising by 10% each decade. Finasteride inhibits 5-alpha reductase (5AR) and is used to treat both disorders, despite offering limited clinical benefits accompanied by significant adverse side effects. Building on our previous work demonstrating the efficacy of naturally derived 5AR inhibitors (such as stigmasterol and beta sitosterol), we hypothesize that targeting 5AR as well as inflammatory pathways may yield improved efficacy in AGA and BPH. Here we address these dual pathomechanisms by examining the potency of a novel composition using in vitro assays of representative cell lines for AGA (hair follicle dermal papilla cells) and BPH (LNCaP prostate cells), respectively. Exposure of cells to the novel test composition down-regulated mRNA expression profiles characteristic of both disease processes, which outperformed finasteride. Changes in mRNA expression were corroborated at the protein level as assessed by western blotting. These studies provide proof of concept that novel, naturally derived compositions simultaneously targeting 5AR and inflammatory mediators may represent a rational approach to treating AGA and BPH. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Inibidores de 5-alfa Redutase/uso terapêutico , Alopecia/tratamento farmacológico , Androgênios/metabolismo , Carnitina/uso terapêutico , Finasterida/uso terapêutico , Folículo Piloso/metabolismo , Fitoterapia/métodos , Hiperplasia Prostática/tratamento farmacológico , Esteróis/farmacologia , Ácido Tióctico/uso terapêutico , Inibidores de 5-alfa Redutase/administração & dosagem , Carnitina/administração & dosagem , Finasterida/administração & dosagem , Humanos , Masculino , Hiperplasia Prostática/complicações , Ácido Tióctico/administração & dosagem
18.
Exp Physiol ; 100(6): 698-707, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25809647

RESUMO

NEW FINDINGS: What is the central question of this study? We investigated whether the LPL gene rs283 polymorphism affects exercise-induced changes in body composition and lipid and glucose metabolism in obese adolescents and whether it is functional. What is the main finding and its importance? Chinese obese adolescents of Han nationality with the GG genotype of the rs283 polymorphism were more sensitive to exercise-induced reduction of the body fat percentage, insulin resistance and plasma triglyceride levels. The G allele can significantly increase reporter gene expression level, which may be the molecular reason for the difference in exercise-induced parameter changes among obese adolescents. The aim of this investigation was to explore the association between the rs283 polymorphism located in the lipoprotein lipase (LPL) gene and exercise-induced changes in body composition and lipid and glucose metabolism in obese adolescents and to probe into the molecular regulatory mechanisms. Fifty-five obese adolescents of Han nationality underwent aerobic training for 4 weeks. Body composition and lipid and glucose metabolic parameters were tested before and after the training. The rs283 polymorphism was genotyped by PCR-restriction fragment length polymorphism, and association analysis with the weight-reducing effect was performed. The regulatory mechanisms of the rs283 polymorphism were explored through the dual-luciferase reporter assay. Exercise-induced change rates were as follows: the change in body fat percentage of GG genotype groups was 3.37 ± 1.60, significantly higher than that of GA genotype groups (2.09 ± 1.53, P < 0.01); the change in the homeostasis model assessment of insulin resistance was 0.52 ± 0.13, obviously higher than that of GA genotype groups (0.44 ± 0.10, P < 0.05); and the change in triglyceride was 51.91 ± 6.56, much higher than that of GA genotype groups (47.06 ± 5.36, P < 0.01). The relative luciferase activity of the reporter gene in recombinant vector carrying the G allele was 2.67 ± 0.22, markedly higher than that in recombinant vector carrying the A allele (1.63 ± 0.03, P < 0.01). Chinese obese adolescents of Han nationality with GG genotype of the rs283 polymorphism were more sensitive to exercise-induced parameter changes. The G allele can improve reporter gene expression level, indicating the effects of rs283 on gene expression.


Assuntos
Metabolismo Energético , Terapia por Exercício , Lipase Lipoproteica/genética , Obesidade Infantil/genética , Obesidade Infantil/terapia , Polimorfismo Genético , Adiposidade , Adolescente , Fatores Etários , Povo Asiático/genética , Biomarcadores/sangue , Glicemia/metabolismo , Restrição Calórica , China/epidemiologia , Feminino , Frequência do Gene , Genótipo , Células HEK293 , Humanos , Lipídeos/sangue , Masculino , Obesidade Infantil/sangue , Obesidade Infantil/enzimologia , Obesidade Infantil/etnologia , Obesidade Infantil/fisiopatologia , Fenótipo , Fatores Sexuais , Fatores de Tempo , Transfecção , Resultado do Tratamento , Redução de Peso
19.
J Immunol ; 190(7): 3687-95, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23436936

RESUMO

The negative feedback mechanism is essential to maintain effective immunity and tissue homeostasis. 1,25-dihydroxyvitamin D (1,25[OH]2D3) modulates innate immune response, but the mechanism remains poorly understood. In this article, we report that vitamin D receptor signaling attenuates TLR-mediated inflammation by enhancing the negative feedback inhibition. Vitamin D receptor inactivation leads to hyperinflammatory response in mice and macrophage cultures when challenged with LPS, because of microRNA-155 (miR-155) overproduction that excessively suppresses suppressor of cytokine signaling 1, a key regulator that enhances the negative feedback loop. Deletion of miR-155 attenuates vitamin D suppression of LPS-induced inflammation, confirming that 1,25(OH)2D3 stimulates suppressor of cytokine signaling 1 by downregulating miR-155. 1,25(OH)2D3 downregulates bic transcription by inhibiting NF-κB activation, which is mediated by a κB cis-DNA element located within the first intron of the bic gene. Together, these data identify a novel regulatory mechanism for vitamin D to control innate immunity.


Assuntos
Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , MicroRNAs/genética , Transdução de Sinais/efeitos dos fármacos , Proteínas Supressoras da Sinalização de Citocina/genética , Receptores Toll-Like/metabolismo , Vitamina D/análogos & derivados , Animais , Linhagem Celular , Citocinas/imunologia , Citocinas/metabolismo , Ativação Enzimática/efeitos dos fármacos , Retroalimentação Fisiológica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hipersensibilidade/genética , Hipersensibilidade/imunologia , Inflamação/imunologia , Inflamação/metabolismo , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Knockout , Modelos Biológicos , NF-kappa B/metabolismo , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Proteína 1 Supressora da Sinalização de Citocina , Transcrição Gênica/efeitos dos fármacos , Vitamina D/farmacologia
20.
J Phys Chem A ; 119(49): 11882-90, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26595194

RESUMO

In this work, the structures, energetics, and tautomerizations in 3-hydroxyisoquinoline (3HIQ) in both the ground state and the excited state have been theoretically investigated by the MP2, TDDFT, and CASPT2 methods, respectively. The solvent effect including the implicit solvent and explicit solvent on the structures, energetics, and tautomeizations are revealed. We found that the explicit solvent plays a more important role in the structures, energetics, and tautomerizations in 3HIQ than implicit solvent in both the ground state and the excited state. The proton transfer is more facilitated in explicit solvent (water or methanol) compared to that in the gas phase and in the implicit solvent in the excited state, and the reactive role of the molecular solvent is found to be related with the two linear hydrogen bonds.

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