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1.
J Food Sci ; 88(1): 513-522, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36463413

RESUMEN

To date, few studies have been conducted on the relationship between postbiotics and air pollution, and there is limited knowledge if postbiotic and probiotic have synergistic effects. Therefore, we created a PM-induced lung inflammation mice model and demonstrated the effect of probiotic, postbiotic, and their combination treatment on attenuation of PM2.5-induced lung damage and allergic response. The mice were intratracheally given PM2.5 triggering conditions of acute lung damage and allergic response. Our results showed that individual treatment of probiotic and postbiotic reduced body weight loss by 47.1% and 48.9%, but the results did not show any effect on polarizing IFN-γ/IL-4 ratio. In addition, PM2.5-induced overactive expression of IgE treated by probiotic and postbiotic was reduced by 33.2% and 30.4%, respectively. While combination treatment of probiotic and postbiotic exerted a synergistic effect, especially considerably on improving IgE reduction by 57.1%, body weight loss by 78.3%, and IFN-γ/IL-4 ratio boost by 87.5%. To sum up the above functionality, these research findings may help establish a novel platform for postbiotic application, formulation, and mechanistic selection with regard to PM2.5-induced lung injury. PRACTICAL APPLICATION: Allergic inflammation caused by PM2.5 is not like common allergens (ex. Pollens, ovalbumin, dust mites), which simply skewing Th1/Th2 polarization to Th2. Thus using probiotics screened by Th1-skewing criteria might not be the best choice to treat on PM2.5-induced symptoms. This research proposed a combination of probiotics and postbiotics on modulating immunity homeostasis, and consequently attenuating complications of PM2.5-induced lung damage. These research findings may help establish a novel platform for postbiotic application, formulation and mechanistic selection with regard to PM2.5-induced lung injury.


Asunto(s)
Hipersensibilidad , Lesión Pulmonar , Neumonía , Probióticos , Animales , Ratones , Lesión Pulmonar/inducido químicamente , Lesión Pulmonar/terapia , Lesión Pulmonar/metabolismo , Interleucina-4/metabolismo , Interleucina-4/farmacología , Pulmón , Hipersensibilidad/terapia , Hipersensibilidad/metabolismo , Material Particulado/toxicidad , Inmunoglobulina E , Pérdida de Peso , Citocinas/metabolismo , Ovalbúmina/efectos adversos , Ratones Endogámicos BALB C
2.
Nutrients ; 13(8)2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-34444952

RESUMEN

Cisplatin-induced nephrotoxicity is associated with gut microbiota disturbance. The present study aimed to investigate whether supplementation of Lactobacillus reuteri and Clostridium butyricum (LCs) had a protective effect on cisplatin-induced nephrotoxicity through reconstruction of gut microbiota. Wistar rats were given different treatments: control, cisplatin (Cis), cisplatin + C. butyricum and L. reuteri (Cis+LCs), and C. butyricum and L. reuteri (LCs). We observed that cisplatin-treated rats supplemented with LCs exhibited significantly decreased renal inflammation (KIM-1, F4/80, and MPO), oxidative stress, fibrosis (collagen IV, fibronectin, and a-SMA), apoptosis, concentration of blood endotoxin and indoxyl sulfate, and increased fecal butyric acid production compared with those without supplementation. In addition, LCs improved the cisplatin-induced microbiome dysbiosis by maintaining a healthy gut microbiota structure and diversity; depleting Escherichia-Shigella and the Enterobacteriaceae family; and enriching probiotic Bifidobacterium, Ruminococcaceae, Ruminiclostridium_9, and Oscillibacter. Moreover, the LCs intervention alleviated the cisplatin-induced intestinal epithelial barrier impairment. This study indicated LCs probiotic serves as a mediator of the gut-kidney axis in cisplatin-induced nephrotoxicity to restore the intestinal microbiota composition, thereby suppressing uremic toxin production and enhancing butyrate production. Furthermore, the renoprotective effect of LCs is partially mediated by increasing the anti-inflammatory effects and maintaining the integrity of the intestinal barrier.


Asunto(s)
Clostridium butyricum , Microbioma Gastrointestinal , Limosilactobacillus reuteri , Nefritis/microbiología , Probióticos/administración & dosificación , Animales , Ácido Butírico/metabolismo , Cisplatino/toxicidad , Modelos Animales de Enfermedad , Inflamación , Riñón/microbiología , Nefritis/inducido químicamente , Nefritis/terapia , Ratas , Ratas Wistar
3.
Neurogastroenterol Motil ; 32(6): e13803, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31989744

RESUMEN

BACKGROUND: Cisplatin is a widely used antineoplastic drug. However, cisplatin-induced dyspepsia syndromes, including delayed gastric emptying, gastric distension, early satiety, nausea, and vomiting, often force patients to take doses lower than those prescribed or even refuse treatment. D-methionine has an appetite-enhancing effect and alleviates weight loss during cisplatin treatment. METHODS: This work established a model of anorexia and dyspepsia symptoms with intraperitoneal injection of cisplatin (5 mg/kg) once a week for three cycles. Presupplementation with or without D-methionine (300 mg/kg) was performed. Orexigenic and anorexigenic hormones (ghrelin, leptin, and glucagon-like peptide-1), tryptophan hydroxylase 1 (TPH1), 5-hydroxytryptamine receptors (5-HT2C and 5-HT3 ), and hypothalamic feeding-related peptides were measured by immunohistochemistry staining, enzyme-linked immunosorbent assay, and real-time PCR assay. KEY RESULTS: Cisplatin administration caused marked decrease in appetite and body weight, promoted adipose and fat tissue atrophy, and delayed gastric emptying and gastric distension, and D-methionine preadministration prior to cisplatin administration significantly ameliorated these side effects. Besides, cisplatin induced an evident increase in serum ghrelin level, TPH1 activity, and 5-HT3 receptor expression in the intestine and decreased plasma leptin levels and gastric ghrelin mRNA gene expression levels. D-methionine supplementation recovered these changes. The expression of orexigenic neuropeptide Y/agouti-related peptide and anorexigenic cocaine- and amphetamine-regulated transcript proopiomelanocortin neurons were altered by D-methionine supplementation in cisplatin-induced anorexia rats. CONCLUSIONS AND INFERENCES: D-methionine supplementation prevents cisplatin-induced anorexia and dyspepsia syndrome possibly by attenuating intestinal tryptophan hydroxylase 1 activity and increasing plasma leptin concentration. Therefore, D-methionine can be used as an adjuvant therapy for treating cisplatin-induced adverse effects.


Asunto(s)
Anorexia/inducido químicamente , Antineoplásicos/administración & dosificación , Cisplatino/administración & dosificación , Dispepsia/inducido químicamente , Mucosa Intestinal/efectos de los fármacos , Leptina/sangre , Metionina/administración & dosificación , Triptófano Hidroxilasa/metabolismo , Animales , Ghrelina/sangre , Hipotálamo/efectos de los fármacos , Hipotálamo/metabolismo , Mucosa Intestinal/metabolismo , Masculino , Ratas Wistar , Receptores de Serotonina 5-HT3/metabolismo
4.
Ther Adv Med Oncol ; 11: 1758835918821021, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30792823

RESUMEN

BACKGROUND: There are close links between chemotherapy-induced intestinal mucositis and microbiota dysbiosis. Previous studies indicated that D-methionine was an excellent candidate for a chemopreventive agent. Here, we investigated the effects of D-methionine on cisplatin-induced mucositis. MATERIALS AND METHODS: Male Wistar rats (176-200 g, 6 weeks old) were given cisplatin (5 mg/kg) and treated with D-methionine (300 mg/kg). Histopathological, digestive enzymes activity, oxidative/antioxidant status, proinflammatory/anti-inflammatory cytokines in intestinal tissues were measured. Next-generation sequencing technologies were also performed to investigate the gut microbial ecology. RESULTS: D-methionine administration increased villus length and crypt depth and improved digestive enzyme (leucine aminopeptidase, sucrose and alkaline phosphatase) activities in the brush-border membrane of cisplatin-treated rats (p < 0.05). Furthermore, D-methionine significantly attenuated oxidative stress and inflammatory reaction and increased interleukin-10 levels in cisplatin-induced intestinal mucositis (p < 0.05). Cisplatin administration resulted in high relative abundances of Deferribacteres and Proteobacteria and a low diversity of the microbiota when compared with control groups, D-methionine only and cisplatin plus D-methionine. Cisplatin markedly increased comparative abundances of Bacteroides caccae, Escherichia coli, Mucispirillum schaedleri, Bacteroides uniformis and Desulfovibrio C21-c20, while Lactobacillus was almost completely depleted, compared with the control group. There were higher abundances of Lactobacillus, Lachnospiraceae, and Clostridium butyrium in cisplatin plus D-methionine rats than in cisplatin rats. D-methionine treatment alone significantly increased the number of Lactobacillus reuteri. CONCLUSION: D-methionine protects against cisplatin-induced intestinal damage through antioxidative and anti-inflammatory effects. By enhancing growth of beneficial bacteria (Lachnospiraceae and Lactobacillus), D-methionine attenuates gut microbiome imbalance caused by cisplatin and maintains gut homeostasis.

5.
Food Funct ; 5(4): 625-34, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24549263

RESUMEN

The ecology of gut microflora, which colonizes all body surfaces, has long coevolved with its hosts in a complicated fashion. Health benefits conferred by gut microflora include defense against invading pathogens, improvement of nutritional bioavailability, and development of the regional and systemic immune systems. The past decade has witnessed growing interest in the fact that the gut microflora affects the host's energy homeostasis by means of various mechanisms, including supplying nourishment from indigestible compounds, producing small biomolecules responsible for lipid profiles, and participating in the absorption, distribution, metabolism and excretion of nutrition. Much in vitro and in vivo research has indicated that aberrant gut microflora plays an important role in the pathogenesis of a wide spectrum of diseases. This is accomplished by a shift in focus, from laying an emphasis on pharmacotherapy to placing more effort on gut microflora normalization. The objectives of this review include illustrating trends in the clinical application of probiotics on diseases, as well as discussing current methodology limitations on probiotic selection. Furthermore, it is expected to shed light on the nature of probiotics, with the aim of giving greater insight into the implications for clinical use of probiotics in the treatment of diseases.


Asunto(s)
Quimioterapia , Probióticos/uso terapéutico , Animales , Tracto Gastrointestinal/microbiología , Humanos , Microbiota
6.
J Dairy Sci ; 97(4): 2009-16, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24485689

RESUMEN

Accumulating studies have suggested that probiotics have beneficial effects on liver injury but the underlying mechanism has remained unclear. Toll-like receptors (TLR) expressed on immune cells and hepatocytes recognize bacterial components that are translocated from the gut into the portal vein. To date, it has been demonstrated that ethanol alone, without microbial components, is able to activate TLR, leading to promotion of proinflammatory cytokine production. Because the enhanced signaling of TLR triggers persistent inflammation, we hypothesized that development of hepatocyte TLR tolerance to repetitive stimulation plays an important role in protecting the liver from hypergeneration of proinflammatory cytokines. In this study, we showed that Lactobacillus casei MYL01 modulated the proinflammatory state induced by ethanol and investigated in detail the mechanism underlying the observation that L. casei MYL01 gave rise to TLR tolerance toward ethanol stimulation. The effects of L. casei MYL01 in the attenuation of ethanol-induced liver damage were due to enhancement of IL-10 production, which limited the proinflammatory process. Furthermore, better defense of hepatocytes against ethanol challenge by treatment of L. casei MYL01 was attributed to previous induction of toll interacting protein (TOLLIP) and suppressor of cytokine signaling (SOCS)1 and SOCS3 expression via activation of TLR1, TLR2, TLR6, and TLR9, an action that cross-regulated ethanol-TLR4-nuclear factor κB signal transduction events. This finding might help establish an in vitro platform for selecting hepatoprotective probiotic strains in terms of ethanol-induced liver damage.


Asunto(s)
Etanol/efectos adversos , Inflamación/metabolismo , Lacticaseibacillus casei/fisiología , Células Hep G2 , Hepatocitos/efectos de los fármacos , Hepatocitos/microbiología , Humanos , Inflamación/microbiología , Interleucina-10/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Hígado/citología , Hígado/efectos de los fármacos , Hígado/microbiología , FN-kappa B/genética , FN-kappa B/metabolismo , Probióticos/farmacología , Interferencia de ARN , Transducción de Señal , Proteína 1 Supresora de la Señalización de Citocinas , Proteína 3 Supresora de la Señalización de Citocinas , Proteínas Supresoras de la Señalización de Citocinas/genética , Proteínas Supresoras de la Señalización de Citocinas/metabolismo , Receptor Toll-Like 2/genética , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo , Receptor Toll-Like 6/genética , Receptor Toll-Like 6/metabolismo , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/metabolismo , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo
7.
BMC Microbiol ; 13: 190, 2013 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-23937116

RESUMEN

BACKGROUND: Crohn's disease and ulcerative colitis are the major types of chronic inflammatory bowel disease occurring in the colon and small intestine. A growing body of research has proposed that probiotics are able to attenuate the inflammatory symptoms of these diseases in vitro and in vivo. However, the mechanism of probiotic actions remains unclear. RESULTS: Our results suggested Lactobacillus plantarum MYL26 inhibited inflammation in Caco-2 cells through regulation of gene expressions of TOLLIP, SOCS1, SOCS3, and IκBα, rather than SHIP-1 and IRAK-3. CONCLUSIONS: We proposed that live/ heat-killed Lactobacillus plantarum MYL26 and bacterial cell wall extract treatments impaired TLR4-NFκb signal transduction through Tollip, SOCS-1 and SOCS-3 activation, thus inducing LPS tolerance. Our findings suggest that either heat-killed probiotics or probiotic cell wall extracts are able to attenuate inflammation through pathways similar to that of live bacteria.


Asunto(s)
Endotoxinas/inmunología , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Intestinos/inmunología , Lactobacillus plantarum/fisiología , Probióticos/farmacología , Células CACO-2 , Humanos , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/inmunología , Intestinos/efectos de los fármacos , Intestinos/microbiología , Lactobacillus plantarum/química , Lipopolisacáridos/inmunología , Fenotipo
8.
J Food Sci ; 76(5): M260-7, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22417436

RESUMEN

Heat-killed lactic acid bacteria not only possess immunomodulatory functions but also provide the advantages of longer product shelf life, easier storage, and more convenient transportation. To establish appropriate heat treatments for the industrial preparation of probiotics with immunomodulatory effects, 4 different heat treatments were used to kill 11 strains of lactic acid bacteria. Comparisons among the strains and with viable forms were carried out in terms of immunomodulatory activity and adhesion to Caco-2 cells. Field-emission scanning electron microscope (FE-SEM) was employed to observe morphological changes in bacteria after heating. Among the 11 viable strains, Lactobacillus gasseri AI-88 was the strongest inducer of interferon-gamma (IFN)-γ and interleukin (IL)-12p70 production. However, after heat treatments its stimulatory ability was attenuated. Heat-killed Enterococcus faecalis YM-73 and Lactobacillus salivarius AP-32 strains showed enhanced stimulation of IFN-γ and IL-12p70 secretion and coincidental decrease in IL-13 production. The adhesion of lactic acid bacteria to Caco-2 cells decreased with increases in temperature. However, heat exposure did not influence immunomodulatory activity. With rising temperature, roughness and unevenness of bacterial cell surfaces increased significantly. The results indicated that heat-killed E. faecalis YM-73 and L. salivarius AP-32 have immunomodulatory ability via increased Th1-associated cytokines and reduced Th2-associated cytokines, switching the immune response from a Th2 toward a Th1 response. These 2 heat-killed strains have the potential for development as commercial products.


Asunto(s)
Calor , Factores Inmunológicos/metabolismo , Lactobacillaceae/crecimiento & desarrollo , Adyuvantes Inmunológicos/metabolismo , Adhesión Bacteriana , Células CACO-2 , Enterococcus faecalis/crecimiento & desarrollo , Humanos , Interferón gamma/metabolismo , Interleucina-12/metabolismo , Interleucina-13/metabolismo , Leucocitos Mononucleares/metabolismo , Microscopía Electrónica de Rastreo/métodos , Probióticos , Balance Th1 - Th2
9.
J Clin Immunol ; 30(6): 830-9, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20683648

RESUMEN

Tyrophagus putrescentiae and Dermatophagoides pteronyssinus are causative factors for the development of airway hypersensitivity. The main objective in this study was to identify the cross-reactive allergens between T. putrescentiae and D. pteronyssinus and investigate their sensitization in patients with allergic rhinitis. The prevalence of sensitization to mites was determined by skin prick tests and histamine release assays. Both immunoblot and ELISA inhibition assays were performed by using the recombinant allergens of T. putrescentiae and D. pteronyssinus. The cross-reactive allergens were identified by using IgE-binding inhibition analysis. The correlations of specific IgE between T. putrescentiae and D. pteronyssinus to group 2 and group 3 mite allergens were compared. A total of 117 allergic rhinitis patients, aged between 16 and 40 years old were recruited to be included in this study. The results showed that 70% (82/117) of allergic rhinitis subjects had skin test positive reactions to D. pteronyssinus or T. putrescentiae. Among these mite-sensitive subjects, there were 81 subjects (81/82) sensitive to D. pteronyssinus and 34 subjects (34/82) sensitive to T. putrescentiae. Among the T. putrescentiae hypersensitive subjects, 97% (33/34) were also sensitized to D. pteronyssinus. In the IgE-binding inhibition analysis, 59% (13/22) subjects had IgE-binding activity of T. putrescentiae that was completely absorbed by D. pteronyssinus, especially components with MW at 16 kDa. In ELISA inhibition testing, 69% of IgE-binding was inhibited by rTyr p 2, and 45% inhibited by rTyr p 3. The titers of IgE antibodies to rTyr p 2 and rDer p 2 were well correlated, but not rTyr p 3 and rDer p 3. In conclusion, most T. putrescentiae sensitized subjects were also sensitized to D. pteronyssinus in young adult allergic rhinitis patients. The complete absorption of IgE binding activity by D. pteronyssinus indicates that T. putrescentiae hypersensitivity might be due to the cross-reactivity, not dual-sensitization of D. pteronyssinus and T. putrescentiae. The IgE-binding titers of group 2 allergens were well correlated and the binding activity of Tyr p 2 could be absorbed by Der p 2, suggesting that group 2 allergens are the major cross-reactive allergen of D. pteronyssinus and T. putrescentiae.


Asunto(s)
Antígenos Dermatofagoides/inmunología , Dermatophagoides pteronyssinus/inmunología , Inmunoglobulina E/metabolismo , Proteínas/inmunología , Rinitis Alérgica Perenne/inmunología , Adolescente , Adulto , Animales , Proteínas de Artrópodos , Reacciones Cruzadas , Liberación de Histamina , Humanos , Inmunización , Prevalencia , Unión Proteica/inmunología , Rinitis Alérgica Perenne/diagnóstico , Rinitis Alérgica Perenne/epidemiología , Pruebas Cutáneas
10.
J Agric Food Chem ; 57(22): 11008-13, 2009 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-19919129

RESUMEN

Fungal immunomodulatory protein, FIP-fve, has been isolated from Flammulina velutipes, and its immunomodulatory effects are believed to be associated with the enhanced activation of IFN-gamma-releasing Th1 cells. However, the mechanisms of FIP-fve-mediated signal transduction in the regulation of interferon-gamma (IFN-gamma) gene expression in human peripheral blood mononuclear cells (PBMCs) are still poorly understood. Using fluo-3 AM, we found that FIP-fve induces a rapid elevation in calcium concentration. ELISA, RT-PCR and Western blot assays demonstrated significant increases in the production and mRNA expression of IFN-gamma and protein kinase C-alpha (PKC-alpha) activation in activated PBMCs, which were abolished by EGTA, nifedipine and GO6976. In conclusion, Ca2+ release and PKC-alpha activation are required for IFN-gamma production induced by FIP-fve in PBMCs.


Asunto(s)
Calcio/metabolismo , Flammulina/química , Proteínas Fúngicas/farmacología , Interferón gamma/biosíntesis , Leucocitos Mononucleares/efectos de los fármacos , Proteína Quinasa C-alfa/metabolismo , Quelantes/farmacología , Activación Enzimática/efectos de los fármacos , Humanos , Interferón gamma/genética , Leucocitos Mononucleares/enzimología , Leucocitos Mononucleares/inmunología , Proteína Quinasa C-alfa/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , ARN Mensajero/análisis , Células TH1/efectos de los fármacos , Células TH1/inmunología
11.
J Agric Food Chem ; 55(26): 11080-6, 2007 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-18038979

RESUMEN

It is believed that probiotics play an important role for the health of the host, including modulation of immune responses. Most studies have focused on the immunomodulatory effects of viable cells of lactic acid bacteria; however, we investigated those of heat-killed cells of lactic acid bacteria in this study. We first observed the effects on immune functions via stimulating splenocytes with three heat-killed Lactobacillus strains. Furthermore, we also investigated the effect of mouse dendritic cells (DCs) treated with these heat-killed Lactobacillus strains on T cell responses. The results showed that these Lactobacillus strains were able to stimulate cell proliferation and interleukin (IL)-10, IL-12 p70, and interferon (IFN)-gamma production but not transforming growth factor (TGF)-beta in splenocytes. In addition, these heat-killed Lactobacillus strains also stimulated high-level secretion of IL-12 p70 in DCs and switched T cells to T helper (Th) 1 immune responses, as evidenced by the elevated secretion of IFN-gamma but not IL-5, IL-13, and TGF-beta. These results showed that lactobacilli play a potentially important role in modulating immune responses and allergic reactions.


Asunto(s)
Antígenos Bacterianos/inmunología , Células Dendríticas/inmunología , Calor , Lactobacillus/inmunología , Bazo/citología , Células TH1/inmunología , Animales , Células Cultivadas , Citocinas/biosíntesis , Femenino , Ratones , Ratones Endogámicos BALB C
12.
J Agric Food Chem ; 55(14): 5604-10, 2007 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-17567149

RESUMEN

Oleosin, a unique structural protein anchoring onto the surface of seed oil bodies by its central hydrophobic domain, stabilizes these lipid-storage organelles as discrete entities. Stable artificial oil bodies have been successfully constituted with native or recombinant oleosins. In this study, recombinant sesame oleosin with 12 residues stepwise truncated from its central hydrophobic domain of 72 residues was overexpressed in Escherichia coli, was purified to homogeneity, and was used for the constitution. Artificial oil bodies constituted by truncated oleosins with the central hydrophobic domain longer than 36 residues were as stable as native sesame oil bodies, and those constituted by truncated oleosins lacking more than half of the original central hydrophobic domain inclined to coalesce upon collision or aggregation.


Asunto(s)
Orgánulos/química , Proteínas de Plantas/química , Proteínas de Plantas/genética , Ingeniería de Proteínas , Semillas/ultraestructura , Escherichia coli/genética , Expresión Génica , Interacciones Hidrofóbicas e Hidrofílicas , Proteínas Recombinantes
13.
J Agric Food Chem ; 55(13): 5092-6, 2007 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-17530857

RESUMEN

The objective of this study was to assess the antiallergic effect of fermented milk prepared, respectively, with Streptococcus thermophilus MC, Lactobacillus acidophilus B, Lactobacillus bulgaricus Lb, L. bulgaricus 448, and Bifidobacterium longum B6. Female BALB/c mice fed fermented milk were immunized intraperitoneally with ovalbumin (OVA)/complete Freund's adjuvant (CFA) to evaluate the immune response by observing the secretion of cytokines IL-2, IL-4, and IFN-gamma and serum antibody IgE. The results showed that supplementation with lactic acid bacteria fermented milk did not significantly change the IL-2 spontaneous and OVA-stimulated secretions of splenocytes. However, both spontaneous and OVA-stimulated secretions of splenocytes from mice fed lactic acid bacteria fermented milk showed significantly (P < 0.05) lower levels of IL-4 (Th2 cytokine) than those from OVA/CFA-immunized mice fed non-fermented milk (OVA/CFA-milk group). The spontaneous secretion of IFN-gamma (Th1 cytokine) by splenocytes from mice fed L. bulgaricus 448 or L. bulgaricus Lb fermented milk significantly increased as compared to that from the OVA/CFA-milk group. The results showed that the ratios of IFN-gamma to IL-4 of both spontaneous and OVA-stimulated secretions in splenocytes from mice fed lactic acid bacteria fermented milk increased significantly as compared to that of PBS- or OVA/CFA-milk groups. The serum levels of OVA-specific IgE in fermented milk fed groups, especially the group fed S. thermophilus MC fermented milk, were significantly lower than those in the OVA/CFA-milk group through a 6 week feeding experiment. The results showed that milk fermented with lactic acid bacteria demonstrated in vivo antiallergic effects on OVA/CFA-immunized mice via increasing the secretion ratio of IFN-gamma/IL-4 (Th1/Th2) by splenocytes and decreasing the serum level of OVA-specific IgE.


Asunto(s)
Fermentación , Hipersensibilidad/prevención & control , Lactobacillus acidophilus/metabolismo , Leche/inmunología , Leche/microbiología , Animales , Femenino , Inmunoglobulina E/sangre , Ratones , Ratones Endogámicos BALB C , Modelos Animales , Ovalbúmina/inmunología , Probióticos/administración & dosificación
14.
Mol Carcinog ; 45(4): 220-9, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16402390

RESUMEN

Telomerase expression is the hallmark of tumor cells, and activation of this ribonucleoprotein complex may be a rate-limiting or critical step in cellular immortalization and oncogenesis. Fungal immunomodulatory protein, FIP-gts, has been isolated from Ganoderma tsugae. In the present study, we expressed and purified the recombinant fungal immunomodulatory protein reFIP-gts in E. coli. We found that reFIP-gts significantly and selectively inhibits the growth of A549 cancer cells while not affecting the growth of normal MRC-5 fibroblasts. The reFIP-gts suppression of telomerase activity is concentration-dependent, due to the downregulation of the telomerase catalytic subunit (hTERT). It also happens at the mRNA level. These results were confirmed by transient transfections of A549 cells with pGL3-Basic plasmid constructs containing the functional hTERT promoter and its E-box-deleted sequences cloned upstream of a luciferase reporter gene. With electrophoretic mobility shift assays and Western blotting, we demonstrated that in response to reFIP-gts, binding of c-myc transcriptional factor to the E-box sequence on the hTERT promoter is inhibited. These results show that reFIP-gts suppresses telomerase activity and inhibits transcriptional regulation of hTERT via a c-myc-responsive element-dependent mechanism. Our findings provide new insight into both the anticancer function of reFIP-gts and the regulation of hTERT/telomerase expression, which may be valuable in the development of a promising chemopreventive agent.


Asunto(s)
Adenocarcinoma/enzimología , Proteínas de Unión al ADN/antagonistas & inhibidores , Proteínas Fúngicas/farmacología , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Lectinas/farmacología , Neoplasias Pulmonares/enzimología , Telomerasa/antagonistas & inhibidores , Transcripción Genética , Adenocarcinoma/genética , Adenocarcinoma/patología , Western Blotting , Proliferación Celular , Células Cultivadas , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Elementos E-Box/genética , Ensayo de Cambio de Movilidad Electroforética , Fibroblastos , Proteínas Fúngicas/genética , Humanos , Lectinas/genética , Luciferasas/metabolismo , Pulmón/metabolismo , Pulmón/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Regiones Promotoras Genéticas/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Telomerasa/genética , Telomerasa/metabolismo , Activación Transcripcional
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