RESUMO
Korean mistletoe (Viscum album L. var. coloratum) is renowned for its medicinal properties, including anti-cancer and immunoadjuvant effects. This study aimed to elucidate the mechanisms by which Korean mistletoe lectin (V. album L. var. coloratum agglutinin; VCA) modulates breast cancer cell apoptosis and macrophage polarization. The specific objectives were to (1) investigate the direct effects of VCA on MCF-7 breast cancer cells and THP-1-derived M1/M2 macrophages; (2) analyze the impact of VCA on the paracrine interactions between these cell types; and (3) compare the efficacy of VCA in 2D vs. 3D co-culture models to bridge the gap between in vitro and in vivo studies. We employed both 2D and 3D models, co-culturing human M1/M2 macrophages with human MCF-7 breast cancer cells in a Transwell system. Our research demonstrated that M1 and M2 macrophages significantly influenced the immune and apoptotic responses of breast cancer cells when exposed to VCA. M1 macrophages exhibited cytotoxic characteristics and enhanced VCA-induced apoptosis in both 2D and 3D co-culture models. Conversely, M2 macrophages initially displayed a protective effect by reducing apoptosis in breast cancer cells, but this protective effect was reversed upon exposure to VCA. Furthermore, our findings illustrate VCA's ability to modulate M1 and M2 polarization in breast cancer cells. Finally, the use of magnetic 3D cell cultures suggests their potential to yield results comparable to conventional 2D cultures, bridging the gap between in vitro and in vivo studies.
Assuntos
Apoptose , Neoplasias da Mama , Técnicas de Cocultura , Macrófagos , Humanos , Apoptose/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/tratamento farmacológico , Células MCF-7 , Feminino , Viscum album/química , Lectinas de Plantas/farmacologia , Células THP-1RESUMO
In this study, we evaluated the effects of Korean mistletoe (Viscum album L. var. coloratum) coated with a biodegradable polymer (Eudragit(®)) wall on the growth of mouse melanoma in vivo. Oral administration of 4% (430 mg/kg/day) enteric-coated mistletoe resulted in a significant reduction in tumor volume on day 14 compared to the negative control group in B16F10 melanoma-inoculated BDF1 mice. When we measured the survival rate, enteric-coated mistletoe-received mice had a higher survival rate after day 12. Also, we investigated the mechanism involving the cancer cell growth inhibition when melanoma cells were treated with Korean mistletoe lectin (Viscum album L. var. coloratum agglutinin, VCA) and its extract in vitro. As a result, a significant G0/G1 arrest was observed in both B16BL6 and B16F10 melanoma cells with VCA or mistletoe extract. In addition, VCA or mistletoe extract induced an increase in both early and late apoptosis in cells. When we studied the molecular mechanism, our results showed that VCA and mistletoe extract can increase activated multiple caspases (caspase-1, 3, 4, 5, 6, 7, 8, and 9), dose-dependently. We also found out that VCA and mistletoe treatment causes a significant decrease in the expression of procaspase-3 and 8.
Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Melanoma Experimental/tratamento farmacológico , Erva-de-Passarinho/metabolismo , Lectinas de Plantas/administração & dosagem , Proteínas Inativadoras de Ribossomos/administração & dosagem , Neoplasias Cutâneas/tratamento farmacológico , Administração Oral , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Apoptose , Caspase 3/metabolismo , Caspase 8/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas In Vitro , Melanoma Experimental/metabolismo , Camundongos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Lectinas de Plantas/química , Lectinas de Plantas/farmacologia , Polímeros/química , Proteínas Inativadoras de Ribossomos/química , Proteínas Inativadoras de Ribossomos/farmacologia , Neoplasias Cutâneas/metabolismo , Análise de SobrevidaRESUMO
We studied the effects, either combined or alone, of lectin from Korean mistletoe (Viscum album var. coloratum agglutinin, VCA) and doxorubicin (DOX) in MCF-7 (estrogen receptor-positive) and MDA-MB231 (estrogen receptor-negative) human breast cancer cells. When VCA and DOX were combined, a strong synergistic effect was shown in cell growth inhibition, compared to VCA or DOX treatment alone. In quantitative apoptosis studies analyzed by flow cytometry, a combination of two agents showed an increase in apoptosis in both cells, compared to agents alone. Also, pro-apoptotic proteins including Bax, Bik, and Puma were increased in both cells, and the survival factor Bcl-2 was inhibited in MCF-7 cells when drugs were combined. Furthermore, VCA combined with DOX mediated S phase arrest, accompanied with a decrease of cell number at G0/G1 phase. This suggests that VCA and DOX combination may possibly lead to a novel strategy for the treatment of breast cancer.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/patologia , Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Sinergismo Farmacológico , Feminino , Humanos , Células MCF-7 , Lectinas de Plantas/isolamento & purificação , Lectinas de Plantas/farmacologia , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Viscum album/químicaRESUMO
Recently, Viscum album var. coloratum agglutinin (VCA) was shown to have various effects on cancer cells. However, most researchers are focused on high concentrations (1-1000 ng/ml) of VCA and its anti-cancer effects. Therefore, we wanted to know whether low concentrations of VCA have an effect on proliferation and invasion of human trophoblast cells (HTR-8/SVneo cell line). Cell proliferations at low concentration of VCA (1-10 pg/ml) were increased over 2-fold relative to the control. Also, gelatinolytic activities of matrix metalloproteinase-2 were increased after VCA treatment, while TIMP-1 expression was reduced. Furthermore, the expression of integrin subunits α5 and ß1 were increased 1.5-fold when cells were treated with low dose of VCA (10 pg/ml). Lastly, VCA was able to promote trophoblast invasion through activation of the Akt signaling pathway. In conclusion, low concentrations of VCA can stimulate the ability of trophoblast cells to invade through the extracellular matrix in vitro.
Assuntos
Lectinas de Plantas/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Trofoblastos/efeitos dos fármacos , Viscum album , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromonas/farmacologia , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Morfolinas/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , RNA Mensageiro/metabolismo , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Trofoblastos/fisiologiaRESUMO
Acanthopanax koreanum Nakai, a well known traditional herb grown in Jeju Island, South of Korea, has been used as a tonic and sedative agent, as well as in the treatment of diabetes and immune diseases. Mutagenicity of two lignans, syringaresinol and tortoside A isolated from A. koreanum, was assessed using Salmonella/microsome (Ames) test. Tester strains used were Salmonella typhimurium TA98, TA100, TA1535, and Escherichia coli WP2uvrA. The mutagenic activity was determined both in the absence or presence of S9 mixture. As a result, tortoside A did not cause any increase in the number of his(+) revertants in S. typhimurium and E. coli WP2uvrA strains in the presence or absence of S9 mix, compared to the controls. Similarly, low concentrations of syringaresinol (750 and 1,500 µg/plate) did not show any mutagenic properties in all bacterial strains, in the presence or absence of S9 mixture. However, in the high concentration of syringaresinol (3,000 µg/plate), the number of revertants were increased in TA1535 strains, in the absence of S9 metabolic activation. Therefore, in vivo experiments such as comet assay are needed to further determine the genotoxic/carciogenic potential of syringaresinol isolated from A. koreanum.
RESUMO
Fatty acid synthase (FAS) has been proposed to be a new drug target for the development of anticancer agents because of the significant difference in expression of FAS between normal and tumour cells. Since a n-hexane-soluble extract from Ginkgo biloba was demonstrated to inhibit FAS activity in our preliminary test, we isolated active compounds from the n-hexane-soluble extract and evaluated their cytotoxic activity in human cancer cells. Three ginkgolic acids 1-3 isolated from the n-hexane-soluble extract inhibited the enzyme with IC(50) values 17.1, 9.2 and 10.5 µM, respectively, and they showed cytotoxic activity against MCF-7 (human breast adenocarcinoma), A549 (human lung adenocarcinoma) and HL-60 (human leukaemia) cells. Our findings suggest that alkylphenol derivatives might be a new type of FAS inhibitor with cytotoxic activity.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Inibidores Enzimáticos/farmacologia , Ácido Graxo Sintases/antagonistas & inibidores , Ginkgo biloba/química , Salicilatos/farmacologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Antineoplásicos Fitogênicos/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/química , Feminino , Células HL-60/efeitos dos fármacos , Hexanos/química , Humanos , Concentração Inibidora 50 , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Estrutura Molecular , Extratos Vegetais/química , Folhas de Planta/química , Salicilatos/química , Salicilatos/isolamento & purificaçãoRESUMO
Ultraviolet (UV) A penetrates deeply into the skin and induces the generation of reactive oxygen species (ROS) causing damage to fibroblasts, which leads to aging of the skin. However, the body has developed an antioxidant defence system against the harmful effects of ROS. Enzymes such as superoxide dismutase (SOD) and catalase (CAT) play critical roles on the removal of excess ROS in living organisms. In this study, the antioxidant activities of anthocyanins (cyanidin 3-galactoside and cyanidin 3-lathyroside) from Acanthopanax divaricatus var. albeofructus (ADA) fruits were investigated by xylenol orange, thiobarbituric acid reactive substances (TBARS), and antioxidant enzyme assay. As a result, generation of H2O2 and lipid peroxide induced by UVA-irradiation in human dermal fibroblast (HDF-N) cells was reduced by treatment of anthocyanins. Also, augmented enzyme (SOD and CAT) activities were observed in UVA-irradiated cells when treated with anthocyanin. In conclusion, the results obtained show that anthocyanins from ADA fruits are potential candidates for the protection of fibroblast against the damaging effects of UVA irradiation. Furthermore, anthocyanin may be a good candidate for antioxidant agent development.
RESUMO
A galactose- and N-acetyl-D-galactosamine-specific lectin (Viscum album L. var. coloratum agglutinin, VCA), which is known for its anticancer activity, was isolated from mistletoe. In this study, we investigated the antimutagenic potentials of VCA by using the pre-incubation method of the Ames test (Salmonella typhimurium TA98 and TA100) in the presence or absence of S9 mixture. Viscum album L. var. coloratum agglutinin was assessed for its antimutagenic properties against the mutagens 2-aminoanthracene (2AA) and furylfuramide (AF-2) for strain TA98, and sodium azide (NaN(3) ) and 2-aminoanthracene (2AA) for strain TA100. The concentrations used for this test compound were 100, 200 and 400 µg per plate. Viscum album L. var. coloratum agglutinin showed moderate, but not negligible, protective effects regarding the antimutagenic properties against the direct-acting mutagens NaN(3) and AF-2. Furthermore, VCA was more effective in preventing the mutagenicity of the indirect-acting mutagen 2-AA (in the presence of S9) when tested with both TA98 and TA100. In conclusion, this report has shown broad ranging antimutagenic effects of VCA to numerous mutagens in TA98 and TA100 Salmonella typhimurium strains. Although the data presented here cannot be applied in vivo, they can support other antimutagenic and anticarcinogenic findings for VCA.
Assuntos
Antimutagênicos/farmacologia , Lectinas de Plantas/farmacologia , Proteínas Inativadoras de Ribossomos/farmacologia , Toxinas Biológicas/farmacologia , Viscum album/química , Acetilgalactosamina/química , Acetilgalactosamina/isolamento & purificação , Acetilgalactosamina/farmacologia , Antracenos/química , Antracenos/isolamento & purificação , Antracenos/farmacologia , Antimutagênicos/química , Antimutagênicos/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Furilfuramida/química , Furilfuramida/isolamento & purificação , Furilfuramida/farmacologia , Galactose/química , Galactose/isolamento & purificação , Galactose/farmacologia , Lectinas de Plantas/química , Lectinas de Plantas/isolamento & purificação , Plantas Medicinais/química , Proteínas Inativadoras de Ribossomos/química , Proteínas Inativadoras de Ribossomos/isolamento & purificação , Proteínas Inativadoras de Ribossomos Tipo 2 , Salmonella typhimurium/efeitos dos fármacos , Toxinas Biológicas/química , Toxinas Biológicas/isolamento & purificaçãoRESUMO
A galactose- and N-acetyl-D-galactosamine-specific lectin (Viscum album L. var. coloratum agglutinin, VCA), which is known for its anticancer activity, was isolated from Korean mistletoe. This study reports a microarray analysis of the effects of VCA on an activated human T cells under various times and concentrations. A total of over 3000 genes were identified whose expression levels were significantly altered against controls after treatment with VCA and anti-CD3/CD28 antibody stimulation on human T-cells over an 8 h period. An analysis of the gene expression profile induced by VCA following incubation in human T cells revealed the activation and inhibition of genes involved in a wide range of immune functions in line with the broad mechanisms of action of VCA. These functions include cytokine gene expression, cell adhesion, cell motility, cell growth and maintenance, cell death, and the response to stress and to external stimulus. This report is aimed at providing the mistletoe research community with a robust database on which further studies could be built.
Assuntos
Anticorpos/farmacologia , Antígenos CD28/imunologia , Complexo CD3/imunologia , Redes Reguladoras de Genes/genética , Proteínas Inativadoras de Ribossomos/química , Linfócitos T/efeitos dos fármacos , Toxinas Biológicas/química , Viscum album/química , Adesão Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Separação Celular , Citocinas/biossíntese , Citocinas/genética , Fragmentação do DNA , DNA Complementar/biossíntese , DNA Complementar/genética , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Análise em Microsséries , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , RNA Mensageiro/biossíntese , Proteínas Inativadoras de Ribossomos Tipo 2 , Transdução de Sinais/efeitos dos fármacos , Estimulação QuímicaRESUMO
The beneficial effects of Acanthopanax divaricatus var. albeofructus (ADA) extracts have been assessed by mutagenic and anti-mutagenic activities by Ames test. Mutation of Salmonella typhimurium strains TA 98, TA 100, TA1535, TA1537, and Escherichia coli WP2 uvr A was assayed in duplicates by the procedure of Maron and Ames in the presence or absence of S9 mix. As a result, ADA extracts were not mutagenic for S. typhimurium strains TA 98, TA 100, TA1535, TA1537, and E. coli by the Ames assay. Anti-mutagenic activity was assayed by the Ames mutagenicity assay using histidine mutant of S. typhimurium strains TA 98 and TA 100, using the plate-incorporation method. 2-Aminoanthrancene (2-AA), 2-(2-furyl)-3-(5-nitro-2-furyl) acrylamide (AF-2), and sodium azide (NaN(3)) were used as the mutagens. ADA extracts showed a strong anti-mutagenic activity against 2-AA-induced mutagenesis which requires liver-metabolizing enzymes, and the same extract exhibited inhibitory effects on AF-2 and NaN(3)-induced mutagenesis in the absence of liver-metabolizing enzymes. The data indicate that ADA extracts contain anti-mutagenic activities against typical mutagens. The anti-mutagenic property of ADA provides additional health supplemental value to the other claimed therapeutic properties of the plant.
Assuntos
Antimutagênicos/farmacologia , Eleutherococcus/química , Mutagênicos/toxicidade , Extratos Vegetais/farmacologia , Animais , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Microssomos Hepáticos/enzimologia , Testes de Mutagenicidade , Folhas de Planta/química , Caules de Planta/química , Ratos , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genéticaRESUMO
BACKGROUND: In this study, we have investigated the effect of Korean red ginseng (KRG) extracts on the production of TNF-α and IL-8 in human keratinocytes. Also, to examine the antioxidative effect of red ginseng extracts, free radical scavenging activity and superoxide dismutase (SOD) activity in human dermal fibroblasts was measured. METHODS: To investigate the effect of KRG in atopic dermatitis, we measured the level of TNF-α and IL-8 secretion in LPS-stimulated human keratinocytes after the treatment of KRG extracts using enzyme-linked immunosorbent assay. Anti-oxidative activity was investigated by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and SOD activity. RESULTS: The stimulation of human keratinocytes with KRG extracts shifted the LPS-induced cytokine secretion toward a more immunosuppressive response. KRG dose-dependently decreased TNF-α and IL-8 production in HaCaT cells and a significant inhibition of TNF-α was shown when cells were treated with 500 and 1,000 µg/ml of KRG extracts. Additionally, KRG extracts showed DPPH radical scavenging and SOD activity in a dose-dependent manner. Particularly, SOD activities of concentrations higher than 60 µg/ml of KRG extracts were significantly different in human dermal fibroblast cells. CONCLUSION: Based on this study, KRG extracts may be a useful immunosuppressive agent in the treatment of atopic dermatitis.
RESUMO
This study was performed to investigate the safety of Alchornea cordifolia, Cnestis ferruginea, Lonchocarpus sericeus, Trema orientalis, and Senna alata in respect to genotoxicity. These five medicinal plants are widely distributed in Africa. They are used as a traditional medicine in many African counties for the treatment of microbial, inflammatory, and stress-related diseases. To evaluate the bacterial reverse mutation of these five medicinal plants, the in vitro Ames test using Salmonella typhimurium TA98, TA100, TA1535, and TA1537, and Escherichia coli WP2uvrA, with or without the addition of S9 mixture was performed. Concentrations used for this test were 625, 2,500, and 5,000 µg per plate. A. cordifolia, C. ferruginea, L. sericeus, and T. orientalis showed negative results in the bacterial reverse mutation test, suggesting that it is potentially safe for these plants to be used in medicinal plants supplements at high doses. However, our experiments suggest that S. alata is a potent mutagen. Therefore, further studies are needed to evaluate the carcinogenicity of S. alata in order to adequately assess the risks for human health.
Assuntos
Connaraceae , Derris , Euphorbiaceae , Testes de Mutagenicidade/métodos , Extratos Vegetais/toxicidade , Senna , Trema , Escherichia coli/efeitos dos fármacos , Humanos , Nigéria , Salmonella typhimurium/efeitos dos fármacosRESUMO
A galactose- and N-acetyl-D-galactosamine-specific lectin (Viscum album L. var. coloratum agglutinin, VCA), which is known for its anti-tumor activity, was isolated from Korean mistletoe. Mistletoe preparations have been given subcutaneously because of the unstability and poor absorption in the GI tract. In this study, we investigated the effect of incubation time and glucose on the VCA transport across the in vitro model of human FAE (follicle-associated epithelium) by two different cell models: Caco-2 cell monolayers mimicking human enterocytes and a model of the human FAE which is mainly composed of M-cells and enterocytes. As a result, the VCA transport across the FAE monolayer cells was higher and faster than the transport across the Caco-2 monolayer cells, and glucose increased VCA transport across both monolayer cells. In addition, IL-12 was secreted from myeloid DC1 and lymphoid DC2.4 cells which were co-treated simultaneously with LPS and VCA. Furthermore, the FAE model associated with underlying immune cells was established and VCA was added to the inserts apically. There was a greater IL-12 secretion in dendritic cells situated below FAE monolayer than Caco-2 monolayer. The results from this study provide important insight into the possible oral application of mistletoe on anti-tumor therapeutics.
Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Células Dendríticas Foliculares/metabolismo , Interleucina-12/metabolismo , Absorção Intestinal , Nódulos Linfáticos Agregados/citologia , Lectinas de Plantas/farmacocinética , Viscum album/química , Imunidade Adaptativa/efeitos dos fármacos , Animais , Transporte Biológico , Células CACO-2 , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Células Dendríticas Foliculares/efeitos dos fármacos , Enterócitos/efeitos dos fármacos , Enterócitos/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Glucose/metabolismo , Humanos , Imunidade Inata/efeitos dos fármacos , Lipopolissacarídeos/toxicidade , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Camundongos , Células Mieloides/efeitos dos fármacos , Células Mieloides/metabolismo , Nódulos Linfáticos Agregados/imunologiaRESUMO
A galactose- and N-acetyl-D-galactosamine-specific lectin (Viscum album L. var. coloratum agglutinin, VCA), which is known for its anti-cancer activity, was isolated from Korean mistletoe. In this study, IEC-6 rat intestinal epithelial cells and IM-9 human B-cells were cultured to determine the effect of VCA on cytokine and immunoglobulin (Ig) secretion. In lipopolysaccharide (LPS)-stimulated IEC-6 cells, VCA significantly shifted the interleukin (IL)-2, IL-5, IL-6, and tumor necrosis factor-alpha (TNF-alpha) secretion toward a more immunostimulatory response. Since intestinal epithelial cell-derived secretions may be capable of affecting local B cell Ig production in a variety of ways, we mimicked this condition by deriving a 2-day culture supernatant from IEC-6 cell line which was treated VCA in the presence or absence of LPS, and adding these supernatants to cultures of IM-9 human B cells. As a result, IgA secretion was significantly enhanced at in the presence of VCA at 10(-8)-10(-4) microg/mL. This study suggests that cytokines derived from IEC by VCA may create an environment which may contribute to the enhancement of IgA secretion seen in mucosal tissues. Overall, the induction of cytokines in intestinal epithelial cells, and IgA in B cells by Korean mistletoe lectin could indicate an enhanced immunosurveillance to prevent intestinal infections or other intestinal pathologies.
Assuntos
Linfócitos B/efeitos dos fármacos , Citocinas/metabolismo , Imunoglobulina A/metabolismo , Fatores Imunológicos/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Lectinas de Plantas/farmacologia , Viscum album , Animais , Linfócitos B/imunologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/metabolismo , Relação Dose-Resposta a Droga , Humanos , Imunidade nas Mucosas/efeitos dos fármacos , Fatores Imunológicos/isolamento & purificação , Interleucinas/metabolismo , Mucosa Intestinal/imunologia , Lipopolissacarídeos/farmacologia , Lectinas de Plantas/isolamento & purificação , Ratos , Fator de Necrose Tumoral alfa/metabolismo , Viscum album/químicaRESUMO
Purified mistletoe lectins are known to have cytotoxic and stimulating activities in the immune system. Mistletoe extract has been given subcutaneously because of its unstablity and poor absorption in the Gastrointestinal (GI) tract. A hallmark of M cells is their capacity to internalize material from the lumen and to transfer it efficiently to the underlying lymphoid cells. Although lectins are the prime candidates for oral vaccine delivery, the mechanisms whereby lectins are taken up, transported by M cells, and affect underlying immune cells remain poorly understood. In this study, uptake mechanism of Korean mistletoe lectin (Viscum album L. var. coloratum aggulutinin, VCA) across the human FAE (follicle associated epithelium) was investigated. An inverted FAE model of co-culture was obtained by a co-culture system of Caco-2 cells and human Raji B lymphocytes, and VCA transport across the in vitro model of human FAE was investigated. There was a greater transport of VCA across FAE monolayer cells than that of Caco-2 monolayer cells. These observations will be useful to assess the transport of other orally administered material in the GI tract.
Assuntos
Mucosa Intestinal/metabolismo , Lectinas/metabolismo , Erva-de-Passarinho/química , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Western Blotting , Células CACO-2 , Linhagem Celular , Técnicas de Cocultura , Ensaios de Seleção de Medicamentos Antitumorais , Ensaio de Imunoadsorção Enzimática , Galectinas/biossíntese , Galectinas/genética , Humanos , Mucosa Intestinal/citologia , Sais de Tetrazólio , TiazóisRESUMO
The anti-cancer activity of mistletoe has been ascribed to a combination of cytotoxic and immunological effects. We previously showed that Korean mistletoe lectin (Viscum album L. var. coloratum agglutinin, VCA) can stimulate IFN-gamma production and modulate proliferation in murine splenocytes. In this study, we investigated the effects of VCA on human peripheral blood mononuclear cells (hPBMC) and T-lymphocytes. The addition of VCA resulted in a significant inhibition of proliferation at higher concentrations (at 2-8 ng/mL, 1-8 ng/mL in hPBMC and T-lymphocytes, respectively) but an induction at lower concentrations (at 4-16 pg/mL, 4-32 pg/mL in hPBMC and T-lymphocytes, respectively). Further studies were carried out to determine if the pro-proliferative or anti-proliferative activity exhibited by VCA was correlated with apoptosis and cytokine secretion. As a result, the apoptotic cell number increased to 26% after 48 h of VCA treatment (10 ng/mL) in the presence of anti-CD3/CD28 antibodies. On the other hand, without anti-CD3/CD28 antibody stimulants, VCA did not arrest cell cycle. In addition, it was shown that VCA could induce IL-2 secretion was dose-dependently increased by VCA in stimulated (anti-CD3/CD28 antibodies) (at 0.25-2 ng/mL) and non-stimulated (at 3-25 pg/mL) human T-lymphocytes. Also, at low and non-toxic concentrations of VCA, the RT-PCR result confirmed the release of pro-inflammatory cytokines such as IL-1alpha, IL-1beta, IL-6, IL-8, and IFN-gamma. These data may suggest new perspective to modulate the balance between cell growth, cytokine production and programmed cell death therapeutically.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Citocinas/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Lectinas de Plantas/farmacologia , Linfócitos T/efeitos dos fármacos , Viscum album , Anticorpos , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Antígenos CD28/imunologia , Complexo CD3/imunologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/genética , Relação Dose-Resposta a Droga , Hemaglutinação/efeitos dos fármacos , Testes de Hemaglutinação , Humanos , Interleucina-2/metabolismo , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Peso Molecular , Lectinas de Plantas/química , Lectinas de Plantas/isolamento & purificação , Preparações de Plantas/farmacologia , RNA Mensageiro/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/patologia , Fatores de Tempo , Viscum album/químicaRESUMO
It is well documented that an extract of European mistletoe has a variety of biological effects, such as the stimulation of cytokine production from immune cells, and additional immunoadjuvant activities. While the European mistletoe has been studied intensively, we know less about Korean mistletoe as a therapeutic plant, especially as a possible immunomodulating drug. This study will investigated the effects of Korean mistletoe lectin (Viscum album L. var. coloratum agglutinin, VCA) on murine splenocytes to investigate whether VCA acts as an immunomodulator, which could lead to improved immune responses in these cells. The results showed that VCA inhibited cell proliferation at higher concentrations (at 1-8 ng/ml) and enhanced cell proliferation at lower concentrations (at 4-32 pg/ml). Further studies were carried out to determine if the proproliferative or anti-proliferative activity exhibited by VCA was correlated with cytokine secretion. Consequently, interferon (IFN)-gamma secretion was decreased in concanavalin A (ConA)-stimulated murine splenocytes by VCA (4-64 ng/ml), but there was no change in IL-4 levels. This suggests that VCA has the ability to modulate murine splenocyte proliferation and can possibly act on the balance of Th1/Th2 cellular immune responses.
Assuntos
Proliferação de Células/efeitos dos fármacos , Citocinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Lectinas de Plantas/farmacologia , Esplenose/patologia , Viscum album/química , Animais , Células Cultivadas , Concanavalina A/farmacologia , Citocinas/genética , Eletroforese em Gel de Poliacrilamida , Expressão Gênica/fisiologia , Testes de Hemaglutinação , Camundongos , Erva-de-Passarinho/químicaRESUMO
Flavonoids, a group of low molecular weight phenylbenzopyrones, have various pharmacological properties including antioxidant, anticancer, bactericidal, and anti-inflammatory. We carried out anti-herpetic assays on 18 flavonoids in five classes and a virus-induced cytopathic effect (CPE) inhibitory assay, plaque reduction assay, and yield reduction assay were performed. When flavonoids were applied at various concentrations to Vero cells infected by HSV-1 and 2, most of the flavonoids showed inhibitory effects on virus-induced CPE. Among the flavonoids, EC, ECG (flavanols), genistein (isoflavone), naringenin (flavanone), and quercetin (flavonol) showed a high level of CPE inhibitory activity. The antiviral activity of flavonoids were also examined by a plaque reduction assay. EC, ECG, galangin, and kaempferol showed a strong antiviral activity, and catechin, EGC, EGCG, naringenin, chrysin, baicalin, fisetin, myricetin, quercetin, and genistein showed moderate inhibitory effects against HSV-1. In these experiments, flavanols and flavonols appeared to be more active than flavones. Furthermore, treatment of Vero cells with ECG and galangin (which previously showed strong antiviral activities) before virus adsorption led to a slight enhancement of inhibition as determined by a yield reduction assay, indicating that an intracellular effect may also be involved.
Assuntos
Antivirais , Flavonoides/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Animais , Contagem de Células , Chlorocebus aethiops , Efeito Citopatogênico Viral/efeitos dos fármacos , Humanos , Indicadores e Reagentes , Células Vero , Ensaio de Placa ViralRESUMO
Flavonoids, a group of low molecular weight phenylbenzopyrones, have various pharmacological properties including antioxidant activity, anticancer, and immunomodulatory effects. In the present study, lipopolysaccharide (LPS) and phorbol 12-myristate 13-acetate/phytohemagglutinin (PMA/PHA) were used as stimulants for RAW 264.7 macrophages and human peripheral blood mononuclear cell (hPBMC), and tumor necrosis factor (TNF)-alpha and interleukin (IL)-2 productions were measured. In addition, flavonoids were examined for their effects on LPS-induced NO production in RAW 264.7 macrophages. The results showed that all compounds were not strongly cytotoxic at the tested concentrations on hPBMC and RAW 264.7 macrophages. On immunomodulatory properties, catechin, epigallocatechin (EGC), naringenin, and fisetin repressed NO production and TNF-alpha secretion. Furthermore, catechin, epigallocatechin gallate (EGCG), epicatechin (EC), luteolin, chrysin, quercetin, and galangin increased IL-2 secretion while EGC, apigenin, and fisetin inhibited the secretion. These results indicated that flavonoids have the capacity to modulate the immune response and have a potential anti-inflammatory activity. There was no obvious structure-activity relationship regard to the chemical composition of the flavonoids and their cell biological effects.
Assuntos
Citocinas/biossíntese , Flavonoides/farmacologia , Leucócitos Mononucleares/metabolismo , Macrófagos/metabolismo , Óxido Nítrico/biossíntese , Adulto , Animais , Células Cultivadas , Humanos , Interleucina-2/biossíntese , Leucócitos Mononucleares/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Camundongos , Pessoa de Meia-Idade , NF-kappa B/fisiologia , Acetato de Tetradecanoilforbol/farmacologia , Fator de Necrose Tumoral alfa/biossínteseRESUMO
Mistletoe lectin has been reported to induce apoptosis in different cancer cell lines in vitro and to show antitumor activity against a variety of tumors in animal models. We previously demonstrated the Korean mistletoe lectin (Viscum album var. coloratum, VCA)-induced apoptosis by down-regulation of Bcl-2 and telomerase activity and by up-regulation of Bax through p53- and p21-independent pathway in hepatoma cells. In the present study, we observed the induction of apoptotic cell death through activation of caspase-3 and the inhibition of telomerase activity through transcriptional down-regulation of hTERT in the VCA-treated A253 cells. We also observed the inhibition of telomerase activity and induction of apoptosis resulted from dephosphorylation of Akt in the survival signaling pathways. In addition, combining VCA with the inhibitors of phosphatidylinositol 3-kinase (PI3-kinase) upstream of Akt, wortmannin and LY294002 showed an additive inhibitory effect of telomerase activity. In contrast, the inhibitor of protein phosphatase 2A (PP2A), okadaic acid inhibited VCA-induced dephosphorylation of Akt and inhibition of telomerase activity. Taken together, VCA induces apoptotic cell death through Akt signaling pathway in correlated with the inhibition of telomerase activity and the activation of caspase-3. From these results, together with our previous studies, we suggest that VCA triggers molecular changes that resulting in the inhibition of cell growth and the induction of apoptotic cell death of cancer cells, which suggest that VCA may be useful as chemotherapeutic agent for cancer cells.