RESUMO
Hepatic steatosis is an initial manifestation of alcoholic liver disease. An imbalance of hepatic lipid processes including fatty acid uptake, esterification, oxidation, and triglyceride secretion leads to alcoholic fatty liver (AFL). However, the precise molecular mechanisms underlying the pathogenesis of AFL remain elusive. Here, we show that mice deficient in microRNAs (miRs)-141 and -200c display resistance to the development of AFL. We found that miR-200c directly targets HNF1 homeobox B (Hnf1b), a transcriptional activator for microsomal triglyceride transfer protein (Mttp), as well as apolipoprotein O (ApoO), an integral component of the mitochondrial contact site and cristae organizing system complex. We show that expression of these miRs is significantly induced by chronic ethanol exposure, which is accompanied by reduced HNF1B and APOO levels. Furthermore, miR-141/200c deficiency normalizes ethanol-mediated impairment of triglyceride secretion, which can be attributed to the restored levels of HNF1B and MTTP, as well as phosphatidylcholine abundance. Moreover, we demonstrate that miR-141/200c deficiency restores ethanol-mediated inhibition of APOO expression and mitochondrial dysfunction, improving mitochondrial antioxidant defense capacity and fatty acid oxidation. Taken together, these results suggest that miR-200c contributes to the modulation of lipid homeostasis in AFL disease by cooperatively regulating Hnf1b and ApoO functions.
Assuntos
Apolipoproteínas , Fígado Gorduroso Alcoólico , Fator 1-alfa Nuclear de Hepatócito , MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Apolipoproteínas/metabolismo , Etanol/metabolismo , Ácidos Graxos/genética , Ácidos Graxos/metabolismo , Fígado Gorduroso Alcoólico/metabolismo , Genes Homeobox , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Homeostase , Fígado/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Triglicerídeos/metabolismoRESUMO
Epigenetic regulation in macrophages plays a crucial role in the inflammatory response of cells. We investigated the role of macrophage histone deacetylase 4 (HDAC4) in diet-induced obesity and non-alcoholic steatohepatitis using macrophage-specific Hdac4 knockout mice (Hdac4MKO ). Hdac4 floxed control (Hdac4fl/fl ) and Hdac4MKO mice were fed a regular chow diet or an obesogenic high-fat/high-sucrose/high-cholesterol (HF/HS/HC) diet for 12 weeks. The loss of macrophage Hdac4, compared with Hdac4fl/fl control, aggravated the diet-induced inflammation in the liver and white adipose tissue only in male mice. Splenic monocytes isolated from male mice fed the HF/HS/HC diet showed increased lipopolysaccharide (LPS) sensitivity and decreased Ly6C-/Ly6C+ ratios in male Hdac4MKO mice, but not in females. Bone marrow-derived macrophages (BMMs) from male Hdac4MKO mice had a lesser efferocytotic capacity but higher proinflammatory gene expression upon LPS stimulation than male Hdac4fl/fl mice. However, female Hdac4MKO BMMs exhibited the opposite responses. The induction of estrogen receptor α (ERα, Esr1) expression by LPS was less in male but more in female Hdac4MKO BMMs than Hdac4fl/fl BMMs. Moreover, overexpression of human HDAC4 decreased basal expression of Esr1 and abolished its induction by LPS. Inhibition of ERα increased Hdac4 with induction of inflammatory genes, whereas activation of ERα decreased Hdac4 with reduction of inflammatory genes in male and female Hdac4fl/fl BMMs treated with LPS. However, regardless of the inhibition or activation of ERα, proinflammatory genes were induced by LPS more in male Hdac4MKO BMMs than Hdac4fl/fl cells, whereas cells in females showed opposite responses. In conclusion, this study suggests that the lack of macrophage Hdac4 aggravates hepatic and white adipose inflammation in male mice with diet-induced obesity and non-alcoholic steatohepatitis, and not in female mice. HDAC4 and ERα appear to counteract each other, but ERα may not be a major player in sex-dependent inflammatory responses in macrophages deficient in HDAC4. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Assuntos
Histona Desacetilases/metabolismo , Macrófagos/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Caracteres Sexuais , Tecido Adiposo/patologia , Animais , Dieta Hiperlipídica/efeitos adversos , Feminino , Inflamação/patologia , Fígado/patologia , Masculino , Camundongos , Camundongos KnockoutRESUMO
Macrophages play an essential role in alcohol-induced inflammation and oxidative stress. We investigated the effects of nicotinamide riboside (NR), a natural nicotinamide adenine dinucleotide (NAD+) precursor, on alcohol-induced inflammation and oxidative stress in macrophages. NR significantly decreased ethanol-induced inflammatory gene expression, with a concomitant decrease in nuclear translocation of nuclear factor κB p65 in RAW 264.7 macrophages and mouse bone marrow-derived macrophages (BMDMs). In macrophages incubated with ethanol or acetaldehyde, NR abolished the accumulation of cellular reactive oxygen species. Ethanol decreased sirtuin 1 (SIRT1) expression and activity, and cellular NAD+ level while inducing pro-inflammatory gene expression. However, NR markedly attenuated the changes. SIRT1 inhibition augmented ethanol-induced inflammatory gene expression, but its activation elicited opposing effects. Also, ethanol did not alter glycolysis but increased glycolytic capacity, glycolytic reserve, and non-glycolytic acidification, with concomitant increases in hypoxia-induced factor 1α expression and activity, phosphorylation of pyruvate dehydrogenase, and extracellular lactate levels. Interestingly, ethanol increased mitochondrial respiration and ATP production but decreased maximal respiration and spare respiration capacity. The latter was linked to decreases in mitochondrial copy numbers. NR abolished the ethanol-induced metabolic changes in the glycolytic and oxidative phosphorylation pathways in RAW 264.7 macrophages. In conclusion, NR exerts anti-inflammatory and antioxidant properties by abrogating the inhibitory effects of ethanol on the SIRT1 pathway by increasing Sirt1 expression and its activator, NAD+. Also, SIRT1 activation and normalization of ethanol-induced changes in NAD+/NADH ratios by NR are likely crucial to counteract the changes in energy phenotypes of macrophages exposed to ethanol.
Assuntos
Inflamação/metabolismo , Macrófagos , Niacinamida/análogos & derivados , Estresse Oxidativo/efeitos dos fármacos , Compostos de Piridínio/farmacologia , Sirtuína 1/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Etanol/efeitos adversos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Niacinamida/farmacologia , Células RAW 264.7RESUMO
Lipid metabolism and inflammation contribute to CVD development. This study investigated whether the consumption of cranberries (CR; Vaccinium macrocarpon) can alter HDL metabolism and prevent inflammation in mice expressing human apo A-I transgene (hApoAITg), which have similar HDL profiles to those of humans. Male hApoAITg mice were fed a modified American Institute of Nutrition-93M high-fat/high-cholesterol diet (16 % fat, 0·25 % cholesterol, w/w; n 15) or the high-fat/high-cholesterol diet containing CR (5 % dried CR powder, w/w, n 16) for 8 weeks. There were no significant differences in body weight between the groups. Serum total cholesterol, non-HDL-cholesterol and TAG concentrations were significantly lower in the control than CR group with no significant differences in serum HDL-cholesterol and apoA-I. Mice fed CR showed significantly lower serum lecithin-cholesterol acyltransferase activity than the control. Liver weight and steatosis were not significantly different between the groups, but hepatic expression of genes involved in cholesterol metabolism was significantly lower in the CR group. In the epididymal white adipose tissue (eWAT), the CR group showed higher weights with decreased expression of genes for lipogenesis and fatty acid oxidation. The mRNA abundance of F4/80, a macrophage marker and the numbers of crown-like structures were less in the CR group. In the soleus muscle, the CR group also demonstrated higher expression of genes for fatty acid ß-oxidation and mitochondrial biogenesis than those of the control. In conclusion, although CR consumption elicited minor effects on HDL metabolism, it prevented obesity-induced inflammation in eWAT with concomitant alterations in soleus muscle energy metabolism.
Assuntos
Frutas , Hipercolesterolemia , Hiperlipidemias , Metabolismo dos Lipídeos , Vaccinium macrocarpon , Animais , Apolipoproteína A-I/genética , Colesterol na Dieta/administração & dosagem , Dieta Hiperlipídica , Ácidos Graxos/metabolismo , Humanos , Hipercolesterolemia/metabolismo , Hiperlipidemias/metabolismo , Inflamação/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Extratos Vegetais/metabolismoRESUMO
PURPOSE: Anti-inflammatory and antioxidant effects of fucoxanthin (FCX), a xanthophyll carotenoid, have been suggested. However, underlying mechanisms are elusive. The objective of this study was to elucidate the mechanisms by which FCX and its metabolites inhibit lipopolysaccharide (LPS)-induced inflammation and oxidative stress in macrophages. METHODS: The effects of the FCX on mRNA and protein expression of pro-inflammatory cytokines and antioxidant genes, and reactive oxygen species (ROS) accumulation were determined in RAW 264.7 macrophages. A potential role of FCX in the modulation of phosphatidylinositol 3-kinase (PI3K)/AKT/nuclear E2-related factor 2 (NRF2) axis was evaluated. RESULTS: FCX significantly decreased LPS-induced interleukin (Il)6, Il1b, and tumor necrosis factor α (Tnf) mRNA abundance and TNFα secretion. FCX attenuated LPS or tert-butyl-hydroperoxide-induced ROS accumulation with concomitant increases in the expression of antioxidant enzymes. Also, trolox equivalent antioxidant capacity assay demonstrated that FCX had a potent free radical scavenging property. FCX markedly increased nuclear translocation of NRF2 in LPS-treated macrophages, consequently inducing its target gene expression. Interestingly, the effect of FCX on NRF2 nuclear translocation was noticeably diminished by LY294002, an inhibitor of PI3K, but not by inhibitors of mitogen-activated protein kinases. Phosphorylation of AKT, a downstream element of PI3K, was also markedly increased by FCX. FCX metabolites, such as fucoxanthinol and amarouciaxanthin A, significantly attenuated LPS-induced ROS accumulation and pro-inflammatory cytokine expression. CONCLUSION: FCX exerts anti-inflammatory and antioxidant effects by the activation of NRF2 in the macrophages activated by LPS, which is mediated, at least in part, through the PI3K/AKT pathway.
Assuntos
Lipopolissacarídeos , Fator 2 Relacionado a NF-E2 , Humanos , Inflamação/tratamento farmacológico , Macrófagos/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Fosfatidilinositol 3-Quinase , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Xantofilas/farmacologiaRESUMO
The objective of this study was to evaluate whether fucoxanthin (FCX) have anti-fibrogenic properties in hepatic stellate cells (HSCs). FCX significantly decreased basal and transforming growth factor ß1 (TGFß1)-induced mRNA levels of fibrogenic genes with concomitant decreases in their protein levels in LX-2â¯cells. The phosphorylation of SMA- and MAD-related protein (SMAD3) was increased by TGFß1, which was attenuated by FCX. Importantly, when LX-2â¯cells were treated with FCX and SIS3, a SMAD3 inhibitor, there was synergistic repression of fibrogenic gene expression. The anti-fibrogenic effect of FCX was also confirmed in primary human HSCs. FCX prevented TGFß1-induced accumulation of reactive oxygen species by diminishing mRNA level of NADPH oxidase 4 (NOX4) in LX-2â¯cells. When FCX was present during the activation of quiescent mouse primary HSCs, it decreased the expression of fibrogenic genes while diminishing intracellular lipid droplets. The results suggest that FCX exerts an anti-fibrogenic effect in HSCs primarily by preventing TGFß1-induced pro-fibrogenic genes expression via inhibition of SMAD3 activation and by inhibiting the activation of quiescent HSCs.
Assuntos
Células Estreladas do Fígado/efeitos dos fármacos , Cirrose Hepática/prevenção & controle , Substâncias Protetoras/farmacologia , Xantofilas/farmacologia , Animais , Linhagem Celular , Células Cultivadas , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Humanos , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismoRESUMO
It has been established that nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) members promote survival by upregulating antiapoptotic genes and that genetic and pharmacological inhibition of NF-κB is required for tumor necrosis factor (TNF)-induced hepatocyte apoptosis. In this study, we demonstrate that this pro-survival pathway is switched to pro-apoptosis under pyruvate dehydrogenase kinase 4 (PDK4)-deficient conditions. PDK4-deficiency triggered hepatic apoptosis concomitantly with increased numbers of aberrant mitochondria, reactive oxygen species (ROS) production, sustained c-Jun N-terminal Kinase (JNK) activation, and reduction of glutathione (GSH). Interestingly, PDK4 retained p65 in cytoplasm via a direct protein-protein interaction. Disruption of PDK4-p65 association promoted p65 nuclear translocation. This, in turn, facilitated p65 binding to the TNF promoter to activate TNF-TNFR1 apoptotic pathway. Pdk4-/- livers were sensitized to Jo2 and D-(+)-Galactosamine /Lipopolysaccharide (GalN/LPS)-mediated apoptotic injury which was prevented by the inhibition of p65 or TNFR1. The pro-survival activity of TNF was shifted, which was switched to a pro-apoptotic activity in Pdk4-/- hepatocytes as a result of impaired activation of pro-survival NF-κB targets. Conclusion: PDK4 is indispensable to dictate the fate of TNF/NF-κB-mediated hepatocyte apoptosis. (Hepatology 2018).
Assuntos
Apoptose , Hepatócitos/metabolismo , NF-kappa B/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Respiração Celular , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Transdução de SinaisRESUMO
Treatment of liver fibrosis is very limited as there is currently no effective anti-fibrotic therapy. Spirulina platensis (SP) is a blue-green alga that is widely supplemented in healthy foods. The objective of this study was to determine whether SP supplementation can prevent obesity-induced liver fibrosis in vivo. Male C57BL/6J mice were randomly assigned to a low-fat or a high-fat (HF)/high-sucrose/high-cholesterol diet or an HF diet supplemented with 2·5 % SP (w/w) (HF/SP) for 16 or 20 weeks. There were no significant differences in body weight, activity, energy expenditure, serum lipids or glucose tolerance between mice on HF and HF/SP diets. However, plasma alanine aminotransferase level was significantly reduced by SP at 16 weeks. Expression of fibrotic markers and trichrome stains showed no differences between HF and HF/SP. Splenocytes isolated from HF/SP fed mice had lower inflammatory gene expression and cytokine secretion compared with splenocytes from HF-fed mice. SP supplementation did not attenuate HF-induced liver fibrosis. However, the expression and secretion of inflammatory genes in splenocytes were significantly reduced by SP supplementation, demonstrating the anti-inflammatory effects of SP in vivo. Although SP did not show appreciable effect on the prevention of liver fibrosis in this mouse model, it may be beneficial for other inflammatory conditions.
Assuntos
Anti-Inflamatórios/farmacologia , Suplementos Nutricionais , Cirrose Hepática/prevenção & controle , Spirulina , Baço/citologia , Animais , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Cirrose Hepática/etiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/complicaçõesRESUMO
PURPOSES: We previously showed that polyphenol-rich blackcurrant extract (BCE) showed a hypocholesterolemic effect in mice fed a high fat diet. As direct cholesterol removal from the body via the intestine has been recently appreciated, we investigated the effect of BCE on the modulation of genes involved in intestinal cholesterol transport using Caco-2 cells as an in vitro model. METHODS: Caco-2 cells were treated with BCE to determine its effects on mRNA and protein expression of genes important for intestinal cholesterol transport, low-density lipoprotein (LDL) uptake, cellular cholesterol content, and cholesterol transport from basolateral to apical membrane of Caco-2 cell monolayers. Cells were also treated with anthocyanin-rich or -poor fraction of BCE to determine the role of anthocyanin on BCE effects. RESULTS: BCE significantly increased protein levels of LDL receptor (LDLR) without altering its mRNA, which consequently increased LDL uptake into Caco-2 cells. This post-transcriptional induction of LDLR by BCE was markedly attenuated in the presence of rapamycin, an inhibitor of mechanistic target of rapamycin complex 1 (mTORC1). In addition, BCE altered genes involved in cholesterol transport in the enterocytes, including apical and basolateral cholesterol transporters, in such a way that could enhance cholesterol flux from the basolateral to apical side of the enterocytes. Indeed, BCE significantly increased the flux of LDL-derived cholesterol from the basolateral to the apical chamber of Caco-2 monolayer. LDLR protein levels were markedly increased by anthocyanin-rich fraction, but not by anthocyanin-free fraction. CONCLUSION: mTORC1-dependent post-transcriptional induction of LDLR by BCE anthocyanins drove the transport of LDL-derived cholesterol to the apical side of the enterocytes. This may represent a potential mechanism for the hypocholesterolemic effect of BCE.
Assuntos
Antocianinas/farmacologia , Colesterol/metabolismo , Frutas/química , Extratos Vegetais/farmacologia , Receptores de LDL/genética , Ribes , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/genética , Células CACO-2 , LDL-Colesterol/metabolismo , Enterócitos/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Alvo Mecanístico do Complexo 1 de Rapamicina/fisiologia , RNA Mensageiro/análise , Receptores de LDL/análise , Receptores de LDL/efeitos dos fármacos , Sirolimo/farmacologia , Transcrição Gênica/efeitos dos fármacosRESUMO
UNLABELLED: With no approved pharmacological treatment, nonalcoholic fatty liver disease (NAFLD) is now the most common cause of chronic liver disease in Western countries and its worldwide prevalence continues to increase along with the growing obesity epidemic. Here, we show that a high-fat high-sucrose (HFHS) diet, eliciting chronic hepatosteatosis resembling human fatty liver, lowers hepatic nicotinamide adenine dinucleotide (NAD(+) ) levels driving reductions in hepatic mitochondrial content, function, and adenosine triphosphate (ATP) levels, in conjunction with robust increases in hepatic weight, lipid content, and peroxidation in C57BL/6J mice. To assess the effect of NAD(+) repletion on the development of steatosis in mice, nicotinamide riboside, a precursor of NAD(+) biosynthesis, was added to the HFHS diet, either as a preventive strategy or as a therapeutic intervention. We demonstrate that NR prevents and reverts NAFLD by inducing a sirtuin (SIRT)1- and SIRT3-dependent mitochondrial unfolded protein response, triggering an adaptive mitohormetic pathway to increase hepatic ß-oxidation and mitochondrial complex content and activity. The cell-autonomous beneficial component of NR treatment was revealed in liver-specific Sirt1 knockout mice (Sirt1(hep-/-) ), whereas apolipoprotein E-deficient mice (Apoe(-/-) ) challenged with a high-fat high-cholesterol diet affirmed the use of NR in other independent models of NAFLD. CONCLUSION: Our data warrant the future evaluation of NAD(+) boosting strategies to manage the development or progression of NAFLD.
Assuntos
Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/patologia , NAD/metabolismo , Niacinamida/análogos & derivados , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Análise de Variância , Animais , Área Sob a Curva , Biópsia por Agulha , Dieta Hiperlipídica/métodos , Modelos Animais de Doenças , Fígado Gorduroso/metabolismo , Imuno-Histoquímica , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , NAD/efeitos dos fármacos , Niacinamida/farmacologia , Compostos de Piridínio , Distribuição Aleatória , Sensibilidade e Especificidade , Resultado do TratamentoRESUMO
BACKGROUND: Non-alcoholic steatohepatitis (NASH) is a subset of non-alcoholic fatty liver disease, the most common chronic liver disease in the U.S. Fibrosis, a common feature of NASH, results from the dysregulation of fibrogenesis in hepatic stellate cells (HSCs). In this study, we investigated whether astaxanthin (ASTX), a xanthophyll carotenoid, can inhibit fibrogenic effects of transforming growth factor ß1 (TGFß1), a key fibrogenic cytokine, in HSCs. METHODS: Reactive oxygen species (ROS) accumulation was measured in LX-2, an immortalized human HSC cell line. Quantitative realtime PCR, Western blot, immunocytochemical analysis, and in-cell Western blot were performed to determine mRNA and protein of fibrogenic genes, and the activation of Smad3 in TGFß1-activated LX-2 cells and primary mouse HSCs. RESULTS: In LX-2 cells, ROS accumulation induced by tert-butyl hydrogen peroxide and TGFß1 was abolished by ASTX. ASTX significantly decreased TGFß1-induced α-smooth muscle actin (α-SMA) and procollagen type 1, alpha 1 (Col1A1) mRNA as well as α-SMA protein levels. Knockdown of Smad3 showed the significant role of Smad3 in the expression of α-SMA and Col1A1, but not TGFß1, in LX-2 cells. ASTX attenuated TGFß1-induced Smad3 phosphorylation and nuclear translocation with a concomitant inhibition of Smad3, Smad7, TGFß receptor I (TßRI), and TßRII expression. The inhibitory effect of ASTX on HSC activation was confirmed in primary mouse HSCs as evidenced by decreased mRNA and protein levels of α-SMA during activation. CONCLUSION: Taken together, ASTX exerted anti-fibrogenic effects by blocking TGFß1-signaling, consequently inhibiting the activation of Smad3 pathway in HSCs. GENERAL SIGNIFICANCE: This study suggests that ASTX may be used as a preventive/therapeutic agent to prevent hepatic fibrosis.
Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Células Estreladas do Fígado/efeitos dos fármacos , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Actinas/genética , Actinas/metabolismo , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Western Blotting , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Células Cultivadas , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Relação Dose-Resposta a Droga , Fibrinolíticos/farmacologia , Fibrose/genética , Células Estreladas do Fígado/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Músculo Liso/química , Fosforilação/efeitos dos fármacos , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Smad3/genética , Xantofilas/farmacologiaRESUMO
Vitamins A and E and select flavonoids in the family of catechins are well-defined small molecules that, if proven to possess immunomodulatory properties, hold promise as vaccine adjuvants and various therapies. In an effort to determine the in vivo immunomodulatory properties of these molecules, we found that although mucosal and systemic vaccinations with a recombinant HIV-1BaL gp120 with either a catechin, epigallo catechin gallate (EGCG) or pro-vitamin A (retinyl palmitate) alone in a vegetable-oil-in-water emulsion (OWE) suppressed antigen-specific responses, the combination of EGCG and vitamin A or E in OWE (Nutritive Immune-enhancing Delivery System, NIDS) synergistically enhanced adaptive B-cell, and CD4(+) and CD8(+) T-cell responses, following induction of relatively low local and systemic innate tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-17, but relatively high levels of early systemic IL-15 responses. For induction of adaptive interferon-γ and TNF-α responses by CD4(+) and CD8(+) T cells, the adjuvant effect of NIDS was dependent on both IL-15 and its receptor. In addition, the anti-oxidant activity of NIDS correlated positively with higher expression of the superoxide dismutase 1, an enzyme involved in reactive oxygen species elimination but negatively with secretion of IL-1ß. This suggests that the mechanism of action of NIDS is dependent on anti-oxidant activity and IL-15, but independent of IL-1ß and inflammasome formation. These data show that this approach in nutritive vaccine adjuvant design holds promise for the development of potentially safer effective vaccines.
Assuntos
Vacinas contra a AIDS/imunologia , Adjuvantes Imunológicos/administração & dosagem , Linfócitos B/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Catequina/imunologia , Interleucina-15/metabolismo , Receptores de Interleucina-15/metabolismo , Vitamina A/administração & dosagem , Vitamina E/administração & dosagem , Animais , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Cultivadas , Sinergismo Farmacológico , Feminino , Proteína gp120 do Envelope de HIV/imunologia , Humanos , Interleucina-15/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Interleucina-15/genéticaRESUMO
OBJECTIVES: A 6-week cross-over study design was used to determine the effect of increased dairy consumption in typically low-dairy consumers (n = 37) with metabolic syndrome (MetS) on systemic inflammation and hepatic enzymes. METHODS: This was a randomized study in which participants consumed low-fat dairy (LFD) (10 oz 1% milk, 6 oz nonfat yogurt, 4 oz 2% cheese) or a carbohydrate-based control (CNT) (1.5 oz granola bar and 12 oz 100% juice) for 6 weeks. After a 4-week washout, they were allocated to the alternate dietary treatment. Inflammatory status was assessed by fasting plasma concentrations of C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), and monocyte chemoattractant -1 (MCP-1). In addition, gene expression of interleukin (IL)-1, IL-6, and TNF-α was evaluated in peripheral blood mononuclear cells isolated from a subset of 17 subjects (13 women, 3 men) at the end of each dietary period. Liver enzymes were also assessed to evaluate whether dairy components would affect hepatic function. RESULTS: Participants had lower concentrations of both hepatic alanine aminotransferase (p < 0.05) and aspartate aminotransferase (p < 0.005) after the LFD period. No significant changes in any of the plasma inflammatory compounds were found when all data were analyzed together. In contrast, expression of IL-1b and IL-6 were reduced by 46% and 63%, respectively, compared to the control period. When stratified by gender, women had lower TNF-α, (p = 0.028) and MCP-1 (p = 0.001) following LFD consumption compared to CNT. In addition, hepatic steatosis index scores were significantly lower (p < 0.001) during the LFD period. CONCLUSIONS: We conclude that three dairy servings per day improved both liver function and systemic inflammation in subjects with MetS.
Assuntos
Laticínios , Inflamação/prevenção & controle , Fígado/enzimologia , Síndrome Metabólica/dietoterapia , Adulto , Estudos Cross-Over , Citocinas/genética , Citocinas/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Síndrome Metabólica/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Obesity is associated with an increased risk of metabolic abnormalities, such as hyperlipidaemia and hyperglycaemia. We investigated whether polyphenol-rich blackcurrant extract (BCE) can prevent high fat/high cholesterol (HF/HC) diet-induced metabolic disturbances in mice. Male C57BL/6J mice were fed a modified AIN-93M diet containing HF/HC (16% fat, 0·25% cholesterol, w/w) or the same diet supplemented with 0·1% BCE (w/w) for 12 weeks. There were no differences in total body weight and liver weight between groups. Plasma total cholesterol (TC) and glucose levels were significantly lower in BCE group than in controls, while plasma TAG levels were not significantly different. There was a decreasing trend in hepatic TAG levels, and histological evaluation of steatosis grade was markedly lower in the livers of mice fed BCE. Although the mRNA levels of major regulators of hepatic cholesterol metabolism, i.e. 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGR) and LDL receptor (LDLR), were not significantly altered by BCE supplementation, protein expression of mature sterol-regulatory element-binding protein and LDLR was significantly increased with no change in HMGR protein. The expression of proprotein convertase subtilisin/kexin type 9 that facilitates LDLR protein degradation, as well as one of its transcriptional regulators, i.e. hepatocyte nuclear factor 4α, was significantly decreased in the livers of mice fed BCE. Taken together, BCE supplementation decreased plasma TC and glucose, and inhibited liver steatosis, suggesting that this berry may be consumed to prevent metabolic dysfunctions induced by diets high in fat and cholesterol.
Assuntos
Colesterol na Dieta/efeitos adversos , Dieta Hiperlipídica/efeitos adversos , Hipoglicemiantes/farmacologia , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Ribes/química , Animais , Glicemia , Peso Corporal , Colesterol na Dieta/administração & dosagem , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Suplementos Nutricionais , Fígado Gorduroso/complicações , Fígado Gorduroso/prevenção & controle , Hidroximetilglutaril-CoA Redutases/genética , Hidroximetilglutaril-CoA Redutases/metabolismo , Hiperglicemia/complicações , Hiperglicemia/prevenção & controle , Hiperlipidemias/complicações , Hiperlipidemias/prevenção & controle , Hipoglicemiantes/análise , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Obesidade/prevenção & controle , Tamanho do Órgão , Extratos Vegetais/análise , Polifenóis/análise , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo , Triglicerídeos/sangueRESUMO
Non-alcoholic fatty liver disease (NAFLD) is significantly associated with hyperlipidaemia and oxidative stress. We have previously reported that astaxanthin (ASTX), a xanthophyll carotenoid, lowers plasma total cholesterol and TAG concentrations in apoE knockout mice. To investigate whether ASTX supplementation can prevent the development of NAFLD in obesity, male C57BL/6J mice (n 8 per group) were fed a high-fat diet (35%, w/w) supplemented with 0, 0.003, 0.01 or 0.03% of ASTX (w/w) for 12 weeks. The 0.03% ASTX-supplemented group, but not the other groups, exhibited a significant decrease in plasma TAG concentrations, suggesting that ASTX at a 0.03% supplementation dosage exerts a hypotriacylglycerolaemic effect. Although there was an increase in the mRNA expression of fatty acid synthase and diglyceride acyltransferase 2, the mRNA levels of acyl-CoA oxidase 1, a critical enzyme in peroxisomal fatty acid ß-oxidation, exhibited an increase in the 0.03% ASTX-supplemented group. There was a decrease in plasma alanine transaminase (ALT) and aspartate transaminase (AST) concentrations in the 0.03% ASTX-supplemented group. There was a significant increase in the hepatic mRNA expression of nuclear factor erythroid 2-related factor 2 and its downstream genes, which are critical for endogenous antioxidant mechanism, in the 0.03% ASTX-supplemented group. Furthermore, there was a significant decrease in the mRNA abundance of IL-6 in the primary splenocytes isolated from the 0.03% ASTX-supplemented group upon lipopolysaccharide (LPS) stimulation when compared with that in the splenocytes isolated from the control group. In conclusion, ASTX supplementation lowered the plasma concentrations of TAG, ALT and AST, increased the hepatic expression of endogenous antioxidant genes, and rendered splenocytes less sensitive to LPS stimulation. Therefore, ASTX may prevent obesity-associated metabolic disturbances and inflammation.
Assuntos
Fígado/efeitos dos fármacos , Obesidade/sangue , Obesidade/tratamento farmacológico , Triglicerídeos/sangue , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Alanina Transaminase/sangue , Animais , Antioxidantes/metabolismo , Aspartato Aminotransferases/sangue , Dieta Hiperlipídica , Suplementos Nutricionais , Expressão Gênica/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipogênese/efeitos dos fármacos , Lipogênese/genética , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/genética , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Obesidade/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Baço/efeitos dos fármacos , Baço/metabolismo , Xantofilas/administração & dosagem , Xantofilas/farmacologiaRESUMO
Histone deacetylase 4 (HDAC4), a class IIa HDAC, has gained attention as a potential therapeutic target in treating inflammatory and metabolic processes based on its essential role in various biological pathways by deacetylating non-histone proteins, including transcription factors. The activity of HDAC4 is regulated at the transcriptional, post-transcriptional, and post-translational levels. The functions of HDAC4 are tissue-dependent in response to endogenous and exogenous factors and their substrates. In particular, the association of HDAC4 with non-histone targets, including transcription factors, such as myocyte enhancer factor 2, hypoxia-inducible factor, signal transducer and activator of transcription 1, and forkhead box proteins, play a crucial role in regulating inflammatory and metabolic processes. This review summarizes the regulatory modes of HDAC4 activity and its functions in inflammation, insulin signaling and glucose metabolism, and cardiac muscle development.
Assuntos
Histona Desacetilases , Inflamação , Transdução de Sinais , Humanos , Histona Desacetilases/metabolismo , Inflamação/metabolismo , Animais , Proteínas Repressoras/metabolismo , Glucose/metabolismo , Insulina/metabolismoRESUMO
We previously demonstrated the beneficial effects of U.S.-grown sugar kelp (Saccharina latissima), a brown seaweed, on reducing serum triglycerides (TG) and total cholesterol (TC) and protecting against inflammation and fibrosis in the adipose tissue of diet-induced obesity mice. In this current study, we aimed to explore whether the dietary consumption of sugar kelp can prevent atherosclerosis using low-density lipoprotein receptor knockout (Ldlr KO) mice fed an atherogenic diet. Eight-week-old male Ldlr KO mice were fed either an atherogenic high-fat/high-cholesterol control (HF/HC) diet or a HF/HC diet supplemented with 6% (w/w) sugar kelp (HF/HC-SK) for 16 weeks. Consumption of sugar kelp significantly increased the body weight gain without altering fat mass and lean mass. Also, there were no significant differences in energy expenditure and physical activities between the groups. The two groups did not show significant differences in serum and hepatic TG and TC levels or the hepatic expression of genes involved in cholesterol and lipid metabolism. Although serum alanine aminotransferase (ALT) activity did not differ significantly between the two groups, there were significant increases in the expression of macrophage markers, including adhesion G protein-coupled receptor E1 and cluster of differentiation 68, as well as tumor necrosis factor alpha in the HF/HC-SK group compared to the HF/HC mice. The consumption of sugar kelp did not elicit a significant effect on the development of aortic lesions. Moreover, lipopolysaccharide-stimulated splenocytes isolated from HF/HC-SK-fed mice showed no significant changes in the mRNA levels of pro-inflammatory genes compared with those from the HF/HC mice. In summary, the consumption of dietary sugar kelp did not elicit anti-atherogenic and hepatoprotective effects in Ldlr KO mice.
Assuntos
Aterosclerose , Camundongos Knockout , Receptores de LDL , Animais , Receptores de LDL/genética , Receptores de LDL/metabolismo , Camundongos , Masculino , Aterosclerose/prevenção & controle , Aterosclerose/genética , Aterosclerose/metabolismo , Triglicerídeos/sangue , Triglicerídeos/metabolismo , Kelp , Camundongos Endogâmicos C57BL , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Colesterol/sangue , Colesterol/metabolismo , Humanos , Metabolismo dos Lipídeos , Algas Comestíveis , LaminariaRESUMO
Vast amounts of dyeing wastewater released from the textile industry can not only cause water pollution but also have negative effects on the human body, such as skin irritation and respiratory diseases. Dye adsorption technology is necessary for the treatment of wastewater discharged from the dyeing industry and for environmental improvement. However, to remove dyeing wastewater, more energy and solvents are used to fabricate adsorbents, or excessive energy is used to filter dyeing wastewater out, resulting in more environmental pollution. Therefore, it is necessary to develop a method of filtering dyeing wastewater in a more environmentally friendly manner by minimizing the use of solvents and energy. In this study, we modified the surface of a textile substrate through UV irradiation to create a monomer capable of facilely bonding with dyes. Employing the UV photografting method, we were able to produce a dye adsorption filter in a more environmentally friendly manner, minimizing solvent usage and heat energy consumption required for absorbent synthesis. At a monomer concentration of 10%, the fabricated filter exhibited a dye removal efficiency of 97.34% after 24 h, all without the need for a pressure treatment or temperature increase. Moreover, it displayed an adsorption capacity of approximately 77.88 mg per 1 g of filter material.
RESUMO
BACKGROUND: Dysphagia is a common problem with potentially serious consequences including malnutrition, dehydration, pneumonia, and death. However, there are challenges in screening for dysphagia in older adults. We assessed the feasibility of using the Clinical Frailty Scale (CFS) as a risk assessment tool for dysphagia. METHODS: This cross-sectional study was conducted at a tertiary teaching hospital from November 2021 to May 2022 and included 131 older patients (age ≥65 years) admitted to acute wards. We used the Eating Assessment Tool-10 (EAT-10), which is a simple measure for identifying individuals at risk of dysphagia, to assess the relationship between EAT-10 score and frailty status as measured using the CFS. RESULTS: The mean age of the participants was 74.3±6.7 years, and 44.3% were male. Twenty-nine (22.1%) participants had an EAT-10 score ≥3. The CFS was significantly associated with an EAT-10 score ≥3 after adjusting for age and sex (odds ratio=1.48; 95% confidence interval [CI], 1.09-2.02). The CFS was able to classify the presence of an EAT-10 score ≥3 (area under the receiver operating characteristic [ROC] curve=0.650; 95% CI, 0. 544-0.756). The cutoff point for predicting an EAT-10 score ≥3 was a CFS of 5 according to the highest Youden index, with a sensitivity of 82.8% and a specificity of 46.1%. The positive and negative predictive values were 30.4% and 90.4%, respectively. CONCLUSION: The CFS can be used as a tool to screen for the risk of swallowing difficulty in older inpatients to determine clinical management encompassing drug administration routes, nutritional support, prevention of dehydration, and further evaluation of dysphagia.
RESUMO
Nonalcoholic steatohepatitis (NASH) is characterized by oxidative stress and inflammatory responses that exacerbate liver injury. The objective of this study was to determine whether the antioxidant and antiinflammatory activities of green tea extract (GTE) would protect against NASH in a model of diet-induced obesity. Adult Wistar rats were fed a low-fat (LF) diet or high-fat (HF) diet containing no GTE or GTE at 1% or 2% (HF+2GTE) for 8 wk. The HF group had greater (P ≤ 0.05) serum alanine (ALT) and aspartate aminotransferases and hepatic lipids than the LF group. Both GTE groups had lower ALT and hepatic lipid than the HF group. In liver and epididymal adipose, the HF group had lower glutathione as well as greater mRNA and protein expression of TNFα and monocyte chemoattractant protein-1 (MCP-1) and NFκB binding activity than the LF group. Compared to the HF group, the HF+2GTE group had greater glutathione and lower protein and mRNA levels of inflammatory cytokines in both tissues. NFκB binding activities at liver and adipose were also lower, likely by inhibiting the phosphorylation of inhibitor of NFκB. NFκB binding activities in liver and adipose (P ≤ 0.05; r = 0.62 and 0.46, respectively) were correlated with ALT, and hepatic NFκB binding activity was inversely related to liver glutathione (r = -0.35). These results suggest that GTE-mediated improvements in glutathione status are associated with the inhibition of hepatic and adipose inflammatory responses mediated by NFκB, thereby protecting against NASH.