RESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: In traditional Chinese medicine (TCM) theory, "Qi" is classified as energetic essence supporting the life activities in human. "Blood" is categorized as nourishing essence and circulating in the body. "Blood" and "Qi" have an intimate relationship. Astragali Radix (AR; root of Astragalus membranaceus (Fisch.) Bge. Var. mongholicus (Bge.) Hsiao) has a broad spectrum of application for "Qi-Blood" enrichment. Astragaloside IV, a major saponin in AR, has therapeutic functions in erythropoietic, cardiovascular and immune systems. However, the efficacy of astragaloside IV in erythrophagocytosis has not been elucidated. AIM OF THE STUDY: The possible functions of astragaloside IV in heme iron recycling during erythrophagocytosis in cultured macrophage were elucidated. METHODS: The translational and transcriptional expressions of heme recycling enzymes were determined after incubating of astragaloside IV for 24 h in cultured macrophage. RESULTS: In astragaloside IV-treated macrophage, the expressions, both RNA and protein levels, of regulators of heme recycling, e.g. heme oxygenase-1 (HO-1), ferroportin (FPN), biliverdin reductase A and B (BVRA, BVRB), were markedly induced in dose-dependent manners. In parallel, the transcriptional activity of antioxidant response element, cloned within an expression vector as pARE-Luc and transfected in cultured macrophages, was markedly induced after a challenge with astragaloside IV in a dose-dependent manner. Moreover, the translocation of Nrf2, a transcriptional factor in regulating expression of heme recycling protein, was induced by astragaloside IV, leading to an enrichment at nucleus fraction. CONCLUSION: Astragaloside IV shed lights in enhancing the expression of heme recycle proteins via Nrf2/ARE signaling pathway.
Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Macrófagos/efeitos dos fármacos , Saponinas/farmacologia , Triterpenos/farmacologia , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Astragalus propinquus , Células Cultivadas , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/química , Heme/metabolismo , Heme Oxigenase-1/metabolismo , Macrófagos/metabolismo , Medicina Tradicional Chinesa , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Células RAW 264.7 , Saponinas/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Triterpenos/isolamento & purificaçãoRESUMO
5-n-Alkylresorcinols (ARs) are abundant in wheat bran and potentially antioxidative, although the neuroprotective mechanism is not fully understood. The neuroprotective effect of wheat bran ARs on H2O2-induced neuronal cells and the relationship between neuroprotection and the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant-response element (ARE) pathway were investigated in this study. Seven homologs were identified in the purified ARs by high-performance liquid chromatography-tandem mass spectrometry. Pretreatment with 80 µg mL-1 ARs alleviated 23% HT22 cell death and the up-regulation of intracellular reactive oxygen species level and malondialdehyde under H2O2 stimulation. The neuroprotection effect was proved by the increase in the Nrf2 nuclear location and up-regulation of mRNA and protein expressions of heme oxygenase-1, NAD(P)H quinone dehydrogenase 1, glutamate-cysteine ligase catalytic subunit, and glutamate-cysteine ligase modifier subunit l. Wheat bran ARs displayed a neuroprotective function, possibly by promoting the endogenous antioxidant defense system. ARs may be regarded as a functional food ingredient for preventing neurodegenerative diseases in the future.
Assuntos
Hipocampo/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Resorcinóis/farmacologia , Triticum/química , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular , Fibras na Dieta/análise , Hipocampo/metabolismo , Malondialdeído/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/genética , Neurônios/metabolismo , Neuroproteção , Fármacos Neuroprotetores/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Espécies Reativas de Oxigênio/metabolismo , Resorcinóis/químicaRESUMO
A comprehensive linear gradient solvent system for centrifugal partition chromatography (CPC) was developed for the bioassay-guided isolation of natural compounds. The gradient solvent system consisted of three different ternary biphasic solvents types: n-hexane-acetonitrile-water (10:2:8, v/v), ethyl acetate-acetonitrile-water (10:2:8, v/v), and water-saturated n-butanol-acetonitrile-water (10:2:8, v/v). The lower phase of the n-hexane-acetonitrile-water (10:2:8, v/v) was used as the stationary phase, while its upper phase, as well as ethyl acetate-acetonitrile-water (10:2:8), and water-saturated n-butanol-acetonitrile-water (10:2:8, v/v) were pumped to generate a linear gradient elution, increasing the mobile phase polarity. We used the gradient CPC to identify antioxidant response elements (AREs), inducing compounds from Centipeda minima, using an ARE-luciferase assay in HepG2 cells, which led to the purification of the active molecules 3-methoxyquercetin and brevilin A. The developed CPC solvent systems allow the separation and isolation of compounds with a wide polarity range, allowing active molecule identification in the complex crude extract of natural products.
Assuntos
Asteraceae/química , Cromatografia Líquida/métodos , Distribuição Contracorrente/métodos , Extratos Vegetais/análise , Solventes/química , 1-Butanol/química , Acetatos/química , Acetonitrilas/química , Elementos de Resposta Antioxidante/efeitos dos fármacos , Bioensaio , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida/instrumentação , Distribuição Contracorrente/instrumentação , Crotonatos/isolamento & purificação , Genes Reporter/efeitos dos fármacos , Células Hep G2 , Hexanos/química , Humanos , Luciferases/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Quercetina/análogos & derivados , Quercetina/isolamento & purificação , Sesquiterpenos/isolamento & purificação , Água/químicaRESUMO
Endoplasmic reticulum (ER) stress designates a cellular response to the accumulation of misfolded proteins, which is related to disease progression in the liver. Luteolin (3',4',5,7-tetrahydroxyflavone) is a phytochemical found frequently in medicinal herbs. Although luteolin has been reported to possess the therapeutic potential to prevent diverse stage of liver diseases, its role in hepatic ER stress has not been established. Thus, the present study aimed to determine the role of luteolin in tunicamycin (Tm)-induced ER stress, and to identify the relevant mechanisms involved in its hepatoprotective effects. In hepatocyte-derived cells and primary hepatocytes, luteolin significantly decreased Tm- or thapsigargin-mediated C/EBP homologous protein (CHOP) expression. In addition, luteolin reduced the activation of three canonical signaling pathways related to the unfolded protein response, and decreased mRNA levels of glucose-regulated protein 78, ER DNA J domain-containing protein 4, and asparagine synthetase. Luteolin also significantly upregulated sestrin 2 (SESN2), and luteolin-mediated CHOP inhibition was blocked in SESN2 (+/-) cells. Moreover, luteolin resulted in phosphorylation of nuclear factor erythroid 2-related factor 2 (Nrf2), as well as increased nuclear Nrf2 expression. Deletion of the antioxidant response element in the human SESN2 promoter inhibited increased luciferase activation by luteolin, suggesting that Nrf2 is a critical transcription factor for luteolin-dependent SESN2 expression. In a Tm-mediated liver injury model, luteolin decreased serum alanine aminotransferase and aspartate aminotransferase activities, prevented degenerative changes and apoptosis of hepatocytes, and inhibited CHOP and glucose-regulated protein 78 expression in hepatic tissues. Therefore, luteolin may be an effective phytochemical to manage ER stress-related liver injury.
Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fígado/efeitos dos fármacos , Luteolina/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Nucleares/metabolismo , Tunicamicina/farmacologia , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Células HEK293 , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fosforilação/efeitos dos fármacos , Fator de Transcrição CHOP/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacosRESUMO
The anshenyizhi compound (AC), a mixture from Chinese medicine herbs, has numerous biological effects. In the present study, the acute exercise-treated mice model was established to explore the antifatigue properties of AC and its underlying mechanisms. AC increased exercise endurance in the weight-loaded forced swimming test and rota-rod test. The antifatigue properties of AC were closely correlated with enhancing the body's exercise endurance by increasing the levels of cyanmethemoglobin, testosterone/corticosterone, and creatine kinase, while decreasing the levels of lactic acid, lactate dehydrogenase, and blood urea nitrogen in serum. Moreover, our results confirmed the antioxidant ability of AC by improving the activities of superoxide dismutase while reducing reactive oxygen species and malondialdehyde levels in serum. The AC also improved the storage of glycogen by increasing the levels of succinate dehydrogenase, and malate dehydrogenase in liver and muscle. Additionally, AC displayed the antifatigue and antiapoptosis effects via regulating Nrf2-mediated oxidative stress, AMPK-related glucose metabolism, and p53 pathways. Our experimental results first provided a support that AC had effects on antifatigue through regulating AMPK/PGC-1α-related energy metabolism and Nrf2/ARE-mediated oxidative stress. Consequently, AC could be developed into a new functional food supplement for the prevention and treatment of diseases related to fatigue in the future.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Medicamentos de Ervas Chinesas/administração & dosagem , Fadiga/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transativadores/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Antioxidantes/metabolismo , Metabolismo Energético , Fadiga/genética , Fadiga/metabolismo , Glicogênio/metabolismo , Humanos , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Fator 2 Relacionado a NF-E2/genética , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Natação , Transativadores/genéticaRESUMO
Two non-animal test methods, KeratinoSens™ and LuSens, have been approved by the Organization of Economic Cooperation and Development (OECD) test guidelines for evaluating the sensitization potential of chemicals, and been positioned as a method for appraising key event (KE)-2, namely, the keratinocyte response component of the Adverse Outcome Pathway (AOP) in sensitization process. However, these two methods require separate cytotoxicity tests to determine the concentrations to be tested in the main test. Therefore, we developed a simple and highly accurate KE-2 test method named α-Sens that uses the dual luciferase assay system and attempted a further application of luciferase-based determination of cell viability to calculate the normalized Antioxidant response element (ARE)-mediated transcriptional activity, named normalized ARE Activity (nAA), to evaluate the sensitizing potential of chemicals. A cell line carrying the ARE-inducible Firefly luciferase reporter gene and Thymidine kinase (TK) promoter-driven Renilla luciferase gene was established and used for the α-Sens. A total of 28 chemicals, consisting of 19 skin sensitizers and nine non-skin sensitizers were tested by this assay system. The α-Sens yielded an accuracy (%), sensitivity (%), and specificity (%) against corresponding values for local lymph node assay of 96.4 %, 95.0 %, and 100 %, respectively, and for human data of 100 % for all. The α-Sens gave clear positive results for phenyl benzoate and eugenol, chemicals for which KeratinoSens™ or LuSens yielded false-negative results, using a new parameter. Our results suggest that better prediction capacity could be achieved by using nAA as a classifier compared to other existing KE-2 test methods. In conclusion, the α-Sens is promising as a simple and highly accurate in vitro skin sensitization test method for evaluation of KE-2.
Assuntos
Elementos de Resposta Antioxidante/efeitos dos fármacos , Dermatite Alérgica de Contato/patologia , Avaliação Pré-Clínica de Medicamentos/métodos , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Alternativas aos Testes com Animais , Animais , Sobrevivência Celular/efeitos dos fármacos , Humanos , Queratinócitos/efeitos dos fármacos , Ensaio Local de Linfonodo , Luciferases/metabolismo , Renilla/enzimologia , Sensibilidade e Especificidade , Testes Cutâneos , Timidina Quinase/metabolismoRESUMO
Lycium barbarum polysaccharides (LBP) are derived from Wolfberry and have antioxidant activities. This study aimed to evaluate the efficacy of LBP for kidney injury in a rat model of sepsis. Male rats were divided randomly to control group (Con), LPS group (LPS), ulinastatin group (ULI), low dose LBP group (LBP-1), middle dose LBP group (LBP-2) and high dose LBP group (LBP-3). After intraperitoneal injection of LPS (5 mg/kg) to make sepsis model (LPS group), 10,000 U/kg ulinastatin were given in ULI group, and 200, 400 and 800 mg/kg LBP was given in LBP-1, -2, -3 group, respectively. Serum IL-1ß, IL-6, IL-8, TNF-α and NF-κB levels were measured by ELISA. Nrf2, Keap1, NF-κB, HO-1 and NQO1 expression levels were detected by PCR and Western blot analysis. We found that LBP decreased the levels of NF-κB and pro-inflammatory cytokines while attenuated kidney injury. In addition, LBP regulated Keap1-Nrf2/ARE signaling pathway in the kidney. In conclusion, LBP attenuates inflammation injury in the kidney via possible regulation of Keap1-Nrf2/ARE signaling.
Assuntos
Injúria Renal Aguda/prevenção & controle , Elementos de Resposta Antioxidante/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Sepse/complicações , Transdução de Sinais/efeitos dos fármacos , Animais , Western Blotting , Citocinas/metabolismo , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo RealRESUMO
This study was aimed to investigate the protective effects of three different mulberry fruit polysaccharide fractions (MFP-I, MFP-II, and MFP-III) against palmitic acid (PA)-induced hepatocyte lipotoxicity and characterize the functional polysaccharide fraction using gel permeation chromatography, high-performance liquid chromatography, Fourier transform infrared spectroscopy, and nuclear magnetic resonance analyses. MFP-I, MFP-II, and MFP-III were isolated from mulberry fruit by stepwise precipitation with 30, 60, and 90% ethanol, respectively. MFP-II at 0.1 and 0.2 mg/mL dramatically attenuated PA-induced hepatic lipotoxicity, while MFP-I and MFP-III showed weak protection. It was demonstrated that MFP-II not only increased nuclear factor erythroid-2-related factor 2 (Nrf2) phosphorylation and its nuclear translocation, thereby activating the Nrf2/ARE signaling pathway, but also enhanced heme oxygenase 1, NAD(P)H:quinone oxidoreductase 1, and γ-glutamate cysteine ligase gene expressions and promoted catalase and glutathione peroxidase activities, which protected hepatocytes against PA-induced oxidative stress and lipotoxicity. Further investigation indicated that the molecular weight of MFP-II was 115.0 kDa, and MFP-II mainly consisted of galactose (30.5%), arabinose (26.2%), and rhamnose (23.1%). Overall, our research might provide in-depth insight into mulberry fruit polysaccharide in ameliorating lipid metabolic disorders.
Assuntos
Hepatócitos/efeitos dos fármacos , Morus/química , Fator 2 Relacionado a NF-E2/metabolismo , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Elementos de Resposta Antioxidante/efeitos dos fármacos , Frutas/química , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo/efeitos dos fármacos , Ácido Palmítico/efeitos adversos , Extratos Vegetais/química , Polissacarídeos/química , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Cerebral ischemic stroke is a severe disease afflicting people worldwide. Phytochemicals play a pivotal role in the discovery of novel therapeutic approaches for the prevention of ischemic stroke. In our continual search for bioactive natural products for the treatment of ischemic stroke, we have evaluated the protective effects of theaflavic acid (TFA) from black tea using PC12 cells injured by oxygen and glucose deprivation/restoration (OGD/R), and investigated the possible mechanisms. The results showed that TFA can protect PC12 cells against OGD/R through increasing cell viability and decreasing intracellular lactate dehydrogenase (LDH) release. Further investigations found that TFA could inhibit the overproduction of intracellular reactive oxygen species (ROS), reduce malondialdehyde content, and elevate superoxide dismutase activity, which implied that TFA suppresses oxidative stress in PC12 cells induced by OGD/R. In addition, overload of intracellular calcium and collapse of the mitochondrial membrane potential were improved in the presence of TFA, and the activity of caspase-3 was significantly reduced by TFA. Western blot analysis showed that the expression of Bcl-2 was up-regulated while Bax was down-regulated. Therefore, it can be concluded that TFA can inhibit mitochondria-dependent apoptosis of PC12 cells induced by OGD/R. In addition, activation of the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response elements (ARE) signaling pathway was explored to elucidate the mechanism by which TFA inhibits ROS-mediated apoptosis in PC12 cells. The results revealed that TFA promoted the translocation of Nrf2 into nuclei, enhanced the transcriptional activity of ARE, and up-regulated expression of downstream HO-1, which indicates that the Nrf2/ARE signaling pathway is involved in the protection by TFA of PC12 cells injured by OGD/R.
Assuntos
Anaerobiose/fisiologia , Apoptose/efeitos dos fármacos , Benzopiranos/farmacologia , Glucose/deficiência , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Caspase 3 , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Glucose/metabolismo , Heme Oxigenase-1/metabolismo , L-Lactato Desidrogenase/metabolismo , Malondialdeído/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Oxigênio/metabolismo , Células PC12 , Compostos Fitoquímicos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2 , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Chá/química , Proteínas de Transporte Vesicular/metabolismoRESUMO
The experiment was conducted to investigate the effects of dietary threonine (Thr) on growth performance and muscle growth, protein synthesis and antioxidant-related signalling pathways of hybrid catfish Pelteobagrus vachelliâ × Leiocassis longirostrisâ. A total of 1200 fish (14·19 (se 0·13) g) were randomly distributed into six groups with four replicates each, fed six diets with graded level of Thr (9·5, 11·5, 13·5, 15·4, 17·4 and 19·3 g/kg diets) for 56 d. Results showed (P < 0·05) that dietary Thr (1) increased percentage weight gain, specific growth rate, feed efficiency and protein efficiency ratio; (2) up-regulated growth hormone (GH), insulin-like growth factor 1 (IGF-1), proliferating cell nuclear antigen, myogenic regulation factors (MyoD, Myf5, MyoG and Mrf4) and myosin heavy chain (MyHC) mRNA levels; (3) increased muscle protein content via regulating the protein kinase B/target of rapamycin signalling pathway and (4) decreased malondialdehyde and protein carbonyl contents, increased catalase, glutathione-S-transferase, glutathione reductase and GSH activities, up-regulated mRNA levels of antioxidant enzymes related to NFE2-related factor 2 and γ-glutamylcysteine ligase catalytic subunit. These results suggest that Thr has a potential role to improve muscle growth and protein synthesis, which might be due to the regulation of GH-IGF system, muscle growth-related gene, antioxidative capacity and protein synthesis-related signalling pathways. Based on the quadratic regression analysis of specific growth rate, the Thr requirement of hybrid catfish (14·19-25·77 g) was estimated to be 13·77 g/kg of the diet (33·40 g/kg of dietary protein).
Assuntos
Ração Animal/análise , Peixes-Gato/crescimento & desenvolvimento , Peixes-Gato/metabolismo , Músculos/efeitos dos fármacos , Treonina/administração & dosagem , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Peixes-Gato/genética , Quimera/crescimento & desenvolvimento , Quimera/metabolismo , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Músculos/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacosRESUMO
OBJECTIVE: Osteoarthritis (OA) is characterized by progressive matrix destruction of articular cartilage. This study aimed to investigate the potential antioxidative and chondroprotective effects and underlying mechanism of Icariin (ICA) in interleukin-1 beta (IL-1ß)-induced extracellular matrix (ECM) degradation of OA cartilage. METHODS: Human chondrocyte cell line HC-A was treated with different doses of ICA, and then MTT assay and PI staining were used to estimate ICA-induced chondrocyte apoptosis. Intracellular ROS and superoxide dismutase (SOD) and glutathione peroxidase (GPX) were measured after treatment by IL-1ß with or without ICA. The mRNA and protein expression levels of redox transcription factor Nrf2 and the downstream effector SOD-1, SOD-2, NQO-1 and HO-1 were assayed to explore the detailed mechanism by which ICA alleviates ECM degradation. Finally, to expound the role of Nrf2 in ICA-mediated chondroprotection, we specifically depleted Nrf2 in human chondrocytes and then pretreated them with ICA followed by IL-1ß. RESULTS: ICA had no cytotoxic effects on human chondrocytes and 10-9 M was selected as the optimum concentration. ROS induced by IL-1ß could drastically activate matrix-degrading proteases and ICA could significantly rescue the matrix degradation and excess ROS generation caused by IL-1ß. We observed that ICA activated the Nrf2/ARE pathway, consequently upregulating the generation of GPX and SOD. Ablation of Nrf2 abrogated the chondroprotective and antioxidative effects of ICA in IL-1ß-treated chondrocytes. CONCLUSION: ICA alleviates IL-1ß-induced matrix degradation and eliminates ROS by activating the Nrf2/ARE pathway.
Assuntos
Elementos de Resposta Antioxidante/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Flavonoides/farmacologia , Interleucina-1beta/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Células Cultivadas , Condrócitos/metabolismo , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/química , Flavonoides/química , Humanos , Interleucina-1beta/metabolismo , Conformação Molecular , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
BACKGROUND: Several studies have found that caffeic acid (CA), a well-known phytochemical, displays important antioxidant and anti-cancer activities. However, no evidence exists on the protective effect and its mechanisms that CA treatment alone has against oxidative stress induced by tert-butyl hydroperoxide (t-BHP) in HepG2 cells. METHODS: Hepatoprotective activities such as cell viability, mRNA expression, and report gene assay were measured using HepG2 cell. Three types of genes and proteins related with detoxification in liver were used for measuring the hepatoprotective effects. Statistical analysis was performed using one-way ANOVA test and differences among groups were evaluated by Tukey's studentized range tests. RESULTS: The present study indicate that treatment with CA up-regulates heme oxygenase-1 (HO-1) and glutamate-cysteine ligase (GCL) mRNA and protein expressions in a CA-dose-dependent manner. In addition, translocation of nuclear factor-E2 p45-related factor (Nrf2) from the cytoplasm to the nucleus and phosphorylation of extracellular signal-regulated kinase, ERK and c-Jun N-terminal kinase, JNK which have been shown to be involved in mitogen-activated protein kinases, MAPKs are significantly enhanced by CA treatment. Furthermore, in cell nuclei, CA enhances the 5'-flanking regulatory region of human antioxidant response element (ARE) and activates the ARE binding site. CONCLUSION: Therefore, CA proved to be a stimulant of the expression of detoxification enzymes such as HO-1, GCLC, and GCLM through the ERK/Nrf2 pathway, and it may be an effective chemoprotective agent for protecting liver damage against oxidative damage.
Assuntos
Ácidos Cafeicos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neoplasias Hepáticas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , terc-Butil Hidroperóxido/toxicidade , Elementos de Resposta Antioxidante/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/genética , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Células Hep G2 , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Neoplasias Hepáticas/genética , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismoRESUMO
Paracetamol is responsible for acute liver failure in humans and experimental animals when taken at high doses and transformed into a reactive metabolite by the liver cytochrome P450. On the other hand, nutmeg is rich with many phytochemical ingredients that are known for their ability to inhibit cytochrome P450. Hence, the present experiment was aimed at studying the hepatoprotective effect of Myristica fragrans (nutmeg), kernel extract (MFKE) in respect to paracetamol (acetaminophen; N-acetyl-p-amino-phenol (APAP))-induced hepatotoxicity in rats, focusing on its antioxidant, anti-inflammatory, and anti-apoptotic activities. Liver toxicity was induced in rats by a single oral administration of APAP (2 g/kg). To evaluate the hepatoprotective effect of MFKE against this APAP-induced hepatotoxicity, rats were pre-treated with either oral administration of MFKE at 300 mg/kg daily for seven days or silymarin at 50 mg/kg as a standard hepatoprotective agent. APAP intoxication caused a drastic elevation in liver function markers (transaminases, alkaline phosphatase, and total bilirubin), oxidative stress indicators (lipid peroxidation and nitric oxide), inflammatory biomarkers (tumour necrosis factor-α, interleukin-1ß, inducible nitric oxide synthase, and nuclear factor ĸB) and the pro-apoptotic BCL2 Associated X (Bax) and caspases-3 genes. Furthermore, analyses of rat liver tissue revealed that APAP significantly depleted glutathione and inhibited the activities of antioxidant enzymes in addition to downregulating two key anti-apoptotic genes: Cellular FLICE (FADD-like IL-1ß-converting enzyme)-inhibitory protein (c-FLIP) and B-cell lymphoma 2 (Bcl-2). Pre-treatment with MFKE, however, attenuated APAP-induced liver toxicity by reversing all of these toxicity biomarkers. This hepatoprotective effect of MFKE was further confirmed by improvement in histopathological findings. Interestingly, the hepatoprotective effect of MFKE was comparable to that offered by the reference hepatoprotector, silymarin. In conclusion, our results revealed that MFKE had antioxidant, anti-inflammatory, and anti-apoptotic properties, and it is suggested that this hepatoprotective effect could be linked to its ability to promote the nuclear factor erythroid 2â»related factor 2 (Nrf2)/antioxidant responsive element (ARE) pathway.
Assuntos
Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Myristica/química , Extratos Vegetais/uso terapêutico , Substâncias Protetoras/uso terapêutico , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/genética , Heme Oxigenase (Desciclizante)/genética , Masculino , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Ratos , Ratos Wistar , Silimarina/farmacologia , Silimarina/uso terapêuticoRESUMO
Olive leaf extract (OLE) has potential health benefits and protects against cytotoxicity in different organs. However, nothing has yet been reported on its potential to prevent cyclophosphamide (CP)-induced nephrotoxicity. This study investigated the possible protective effect of OLE on CP-induced kidney injury in rats, focusing on oxidative stress, inflammation, apoptosis and Nrf2/ARE/HO-1 signaling. Rats received 100 or 200 mg/kg body weight OLE for 15 days and a single injection of 150 mg/kg CP at day 16. CP induced kidney injury evidenced by the significantly increased serum creatinine and urea, and histopathological alterations, including glomerular atrophy, interstitial hemorrhage, dilated urinary space and necrosis. CP-induced rats exhibited increased kidney lipid peroxidation, protein carbonyl, nitric oxide (NO) and pro-inflammatory cytokines, and up-regulated NF-κB, Bax, cytochrome c and caspase-3. OLE ameliorated kidney function markers and prevented CP-induced tissue damage. In addition, OLE significantly prevented oxidative stress, inflammation and apoptosis by enhancing the antioxidant defenses and Bcl-2 expression, and suppressing the pro-inflammatory and pro-apoptotic markers NF-κB, Bax, cytochrome c and caspase-3. OLE up-regulated Nrf2, HO-1 and NQO-1 expression in the kidney of CP-induced rats. In conclusion, OLE has a substantial protective role against CP-induced nephrotoxicity in rats by up-regulating the Nrf2/ARE/HO-1 signaling, enhancing the antioxidant activity and attenuating inflammation and apoptosis.
Assuntos
Elementos de Resposta Antioxidante/efeitos dos fármacos , Ciclofosfamida/toxicidade , Heme Oxigenase (Desciclizante)/biossíntese , Rim/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/biossíntese , Olea , Estresse Oxidativo/efeitos dos fármacos , Animais , Elementos de Resposta Antioxidante/fisiologia , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Relação Dose-Resposta a Droga , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/uso terapêutico , Imunossupressores/toxicidade , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/prevenção & controle , Rim/metabolismo , Rim/patologia , Masculino , Estresse Oxidativo/fisiologia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologiaRESUMO
BACKGROUND: Systemic oxidative stress has been reported to play a central role in the pathogenesis of kidney function decline. The nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway is one of the important endogenous antioxidant stress pathways in cells. This study aims to investigate whether shenduning granule can ameliorate oxidative stress in kidney tissues by activating the Nrf2/ARE pathway, and explores the detailed underlying mechanism. METHODS: A total of 120 male Sprague-Dawley rats were randomly assigned to the sham-operated and operation groups. Rats in the operation group underwent 5/6 nephrectomy. Two weeks later, rats in the operation group were further randomly divided into 5 groups: model group, low-dose, medium-dose and high-dose shenduning granule groups, and losartan group. Rats in each group were given the same volume of corresponding liquid orally. Serum creatinine (SCr), blood urea nitrogen (BUN), 24-h urinary protein, malondialdehyde (MDA) and superoxide dismutase (SOD), Nrf2, heme oxygenase-1 (HO-1), and γ-glutamyl-cysteine synthetase (γ-GCS) were determined. RESULTS: Shenduning granule could markedly elevate HO-1, NRF2, γ-GCS and SOD (p < 0.05), and significantly decreased MDA, 24-h urinary protein, SCr and BUN in rats (p < 0.05). CONCLUSION: Shenduning granule can improve renal antioxidative stress activity in rats, exhibiting a renoprotective effect. The potential mechanism is likely exerted by the activation of the Nrf2/ARE pathway.
Assuntos
Nefropatias/prevenção & controle , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Nefropatias/etiologia , Nefropatias/fisiopatologia , Masculino , Malondialdeído/metabolismo , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Plantas Medicinais/química , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismoRESUMO
Non-small cell lung cancer (NSCLC) has a high mortality rate worldwide. Various treatments strategies have been used against NSCLC including individualized chemotherapies, but innate or acquired cancer cell drug resistance remains a major obstacle. Recent studies revealed that the Kelch-like ECH associated protein 1/Nuclear factor erythroid 2-related factor 2 (Keap1/Nrf2) pathway is intimately involved in cancer progression and chemoresistance. Thus, antagonizing Nrf2 would seem to be a viable strategy in cancer therapy. In the present study a traditional Chinese medicine, triptolide, was identified that markedly inhibited expression and transcriptional activity of Nrf2 in various cancer cells, including NSCLC and liver cancer cells. Consequently, triptolide made cancer cells more chemosensitivity toward antitumor drugs both in vitro and in a xenograft tumor model system using lung carcinoma cells. These results suggest that triptolide blocks chemoresistance in cancer cells by targeting the Nrf2 pathway. Triptolide should be further investigated in clinical cancer trials.
Assuntos
Antineoplásicos Alquilantes/administração & dosagem , Elementos de Resposta Antioxidante/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Diterpenos/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fenantrenos/administração & dosagem , Células A549 , Animais , Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Elementos de Resposta Antioxidante/fisiologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/fisiologia , Compostos de Epóxi/administração & dosagem , Células Hep G2 , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/fisiologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
NF-E2-related factor 2 (NRF2) regulates transcription of phase II cytoprotective enzymes to protect normal cells against oxidative stress. However, a high level of NRF2 offers a growth advantage, chemoresistance, and radioresistance in cancer. In the present study, we have identified convallatoxin as a novel inhibitor of NRF2/ARE. Suppression of NRF2 by convallatoxin was not transcriptionally mediated, but regulated at the level of proteolysis. Convallatoxin activated GSK-3ß and suppression of NRF2 by convallatoxin required the Neh6 domain. Convallatoxin sensitised A549 cells to 5-fluorouracil-mediated cell death by promoting apoptosis. Together, our results provide evidence that convallatoxin might be useful as a chemotherapeutic adjuvant due to its ability to suppress NRF2/ARE.
Assuntos
Elementos de Resposta Antioxidante/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Fluoruracila/farmacologia , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Estrofantinas/farmacologia , Células A549 , Elementos de Resposta Antioxidante/genética , Relação Dose-Resposta a Droga , Humanos , Conformação Molecular , Relação Estrutura-AtividadeRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Oxidative stress is a prominent feature of clinical acute pancreatitis (AP). Coreopsis tinctoria has been used traditionally to treat pancreas disorders like diabetes mellitus in China and Portugal and its flavonoid-rich fraction contain the main phytochemicals that have antioxidant and anti-inflammatory activities. AIM OF THE STUDY: To investigate the effects of flavonoids isolated from C. tinctoria on experimental AP and explore the potential mechanism. MATERIALS AND METHODS: LC-MS based online technique was used to analyse and isolate targeted flavonoids from C. tinctoria. Freshly isolated mouse pancreatic acinar cells were treated with taurocholic acid sodium salt hydrate (NaT, 5â¯mM) with or without flavonoids. Fluorescence microscopy and a plate reader were used to determine necrotic cell death pathway activation (propidium iodide), reactive oxygen species (ROS) production (H2-DCFDA) and ATP depletion (luminescence) where appropriate. AP was induced by 7 repeated intraperitoneal caerulein injections (50⯵g/kg) at hourly interval in mice or retrograde infusion of taurolithocholic acid 3-sulfate disodium salt (TLCS; 5â¯mM, 50⯵L) into the pancreatic duct in mice or infusion of NaT (3.5%, 1â¯mL/kg) in rats. A flavonoid was intraperitoneally administered at 0, 4, and 8â¯h after the first caerulein injection or post-operation. Disease severity, oxidative stress and antioxidant markers were determined. RESULTS: Total flavonoids extract and flavonoids 1-6 (C1-C6) exhibited different capacities in reducing necrotic cell death pathway activation with 0.5â¯mM C1, (2â¯R,3â¯R)-taxifolin 7-O-ß-D-glucopyranoside, having the best effect. C1 also significantly reduced NaT-induced ROS production and ATP depletion. C1 at 12.5â¯mg/kg and 8.7â¯mg/kg (equivalent to 12.5â¯mg/kg for mice) significantly reduced histopathological, biochemical and immunological parameters in the caerulein-, TLCS- and NaT-induced AP models, respectively. C1 administration increased pancreatic nuclear factor erythroid 2-related factor 2 (Nrf2) and Nrf2-medicated haeme oxygenase-1 expression and elevated pancreatic antioxidant enzymes superoxide dismutase and glutathione peroxidase levels. CONCLUSIONS: Flavonoid C1 from C. tinctoria was protective in experimental AP and this effect may at least in part be attributed to its antioxidant effects by activation of Nrf2-mediated pathways. These results suggest the potential utilisation of C. tinctoria to treat AP.
Assuntos
Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Coreopsis , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Pancreatite/tratamento farmacológico , Células Acinares/efeitos dos fármacos , Doença Aguda , Trifosfato de Adenosina/metabolismo , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Heme Oxigenase-1/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Pancreatite/metabolismo , Pancreatite/patologia , Fitoterapia , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismoRESUMO
Stroke involves numerous pathophysiological processes and oxidative stress is considered as a main cellular event in its pathogenesis. The nuclear factor erythroid-2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway plays a key role in inducing phase II detoxifying enzymes and antioxidant proteins and is now considered as a interesting therapeutic target for the treatment of stroke. The objective of this study is to investigate the protective effect of Gualou Guizhi granule (GLGZG) against oxidative stress and explore the protective mechanism of the Nrf2/ARE pathway. In vivo, administration of GLGZG in a rat model of focal cerebral ischemia significantly suppressed oxidative injury by increasing the activity of superoxide dismutase and glutathione level and decreasing reactive oxygen species and malondialdehyde levels. Western blot analysis showed that GLGZG induced nuclear translocation of Nrf2, and combined with real-time PCR results, which indicated that GLGZG up-regulated the Nrf2/ARE pathway. In addition, in cultured PC12 cells, GLGZG protected against H2O2 induced oxidative injury and activated the Nrf2/ARE pathway. All the results demonstrated that GLGZG in the management of cerebral ischemia and H2O2 induced oxidative injury may be associated with activation of Nrf2/ARE signaling pathway.
Assuntos
Elementos de Resposta Antioxidante/efeitos dos fármacos , Antioxidantes/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/prevenção & controle , Masculino , Células PC12 , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/prevenção & controleRESUMO
BACKGROUND: The nuclear factor erythroid 2-related factor 2 (Nrf2) is a potential molecular target for cancer chemoprevention. Si-Wu-Tang (SWT), a popular traditional Chinese medicine for women's health, was reported with a novel activity of cancer prevention. PURPOSE: The present study was aimed to identify the bioactive constituents in SWT responsible for the Nrf2 activating and cancer preventive activity and explore the pharmacological mechanisms. METHODS: Nine compounds detectable from various batches of SWT were ranked using in silico molecular docking based on their ability to interfere the forming of Nrf2-Keap1 complex. The predicted Nrf2 activating effect was validated using the antioxidant response element (ARE) luciferase reporter assay and quantitative RT-PCR analysis for select Nrf2 regulated genes Hmox1, Nqo1 and Slc7a11. The antimutagenic activity of the compounds were determined by the Ames test. The chemopreventive activity of these compounds were assessed on EGF-induced neoplastic transformation of JB6 P+ cells, an established non-cancerous murine epidermal model for studying tumor promotion and identifying cancer preventive agents. These compounds were further characterized using luciferase reporter assay on EGF-induced activation of AP-1, a known transcription factor mediating carcinogenesis. RESULTS: Three of the nine compounds predicted as Nrf2 activators by molecular docking, gallic acid (GA), Z-liguistilide (LIG), and senkyunolide A (SA), were confirmed with highest potency of increasing the Nrf2/ARE promoter activity and upregulating the expression of Hmox1, Nqo1 and Slc7a11. In addition, GA, LIG and SA exhibited an antimutagenic activity against the direct mutagen 2-nitrofluorene while no mutagenic effects were observed at the same time in Ames test. At nontoxic concentrations, GA, LIG, and SA inhibited EGF-induced neoplastic transformation of JB6 P+ cells. Combined treatment of GA, LIG and SA, in the same ratio as detected in SWT, showed enhanced effect against JB6 transformation compared with that of the single compound alone. GA, LIG and SA, alone or in combination, suppressed EGF-induced activation of AP-1. CONCLUSION: We identified three bioactive constituents in SWT responsible for the Nrf2 activating and cancer preventive activity. This study provides evidence supporting novel molecular basis of SWT in cancer prevention.