RESUMEN
Hepatocellular carcinoma (HCC) is a tumor with minimal chance of cure due to underlying liver diseases, late diagnosis, and inefficient treatments. Thus, HCC treatment warrants the development of additional strategies. Lactoferrin (Lf) is a mammalian multifunctional iron-binding glycoprotein of the innate immune response and can be found as either a native low iron form (native-Lf) or a high iron form (holo-Lf). Bovine Lf (bLf), which shares many functions with human Lf (hLf), is safe for humans and has several anticancer activities, including chemotherapy boost in cancer. We found endogenous hLf is downregulated in HCC tumors compared with normal liver, and decreased hLf levels in HCC tumors are associated with shorter survival of HCC patients. However, the chemoprotective effect of 100% iron saturated holo-bLf on experimental hepatocarcinogenesis has not yet been determined. We aimed to evaluate the chemopreventive effects of holo-bLf in different HCC models. Remarkably, a single dose (200 mg kg-1) of holo-bLf was effective in preventing early carcinogenic events in a diethylnitrosamine induced HCC in vivo model, such as necrosis, ROS production, and the surge of facultative liver stem cells, and eventually, holo-bLf reduced the number of preneoplastic lesions. For an established HCC model, holo-bLf treatment significantly reduced HepG2 tumor burden in xenotransplanted mice. Finally, holo-bLf in combination with sorafenib, the advanced HCC first-line treatment, synergistically decreased HepG2 viability by arresting cells in the G0/G1 phase of the cell cycle. Our findings provide the first evidence suggesting that holo-bLf has the potential to prevent HCC or to be used in combination with treatments for established HCC.
Asunto(s)
Carcinoma Hepatocelular , Hierro , Lactoferrina , Neoplasias Hepáticas , Lactoferrina/farmacología , Lactoferrina/administración & dosificación , Animales , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/prevención & control , Neoplasias Hepáticas/tratamiento farmacológico , Bovinos , Hierro/metabolismo , Humanos , Ratones , MasculinoRESUMEN
Bovine lactoferrin (bLf), a component of milk and a dietary supplement, modulates intestinal immunity at effector and inductor sites. Considering the regional difference in intestinal compartments and the dynamics of local cytokine-producing cells in the gut across time, the aim of this work was to characterize the effects of bLf on the proximal small intestine in a BALB/c murine model of oral administration. Male BALB/c mice were treated with oral bLf vs. saline control as mock by buccal deposition for 28 days. Intestinal secretions were obtained at different time points and cells were isolated from Peyer's patches (PP) and lamina propria (LP) of the proximal small intestine as representative inductor and effector sites, respectively. Total and specific anti-bLF IgA and IgM were determined by enzyme-immuno assay; the percentages of IgA+ and IgM+ plasma cells (PC) and cytokine-producing CD4+ T cells of PP and LP were analyzed by flow cytometry. We found that total and bLf-specific IgA and IgM levels were increased in the intestinal secretions of the bLf group in comparison to mock group and day 0. LP IgA+ PC and IgM+ PC presented an initial elevation on day 7 and day 21, respectively, followed by a decrease on day 28 in comparison to mock. Higher percentages of CD4+ T cells in LP were found in the bLf group. Cytokines-producing CD4+ T cells populations presented a pattern of increases and decreases in the bLf group in both LP and PP. Transforming growth factor beta (TGF-ß)+ CD4+ T cells showed higher percentages after bLf administration with a marked peak at day 21 in both LP and PP in comparison to mock-treated mice. Oral bLf exhibits complex immune properties in the proximal small intestine, where temporal monitoring of the inductor and effector compartments reveals patterns of rises and falls of different cell populations. Exceptionally, TGF-ß+ CD4+ T cells show consistent higher numbers after bLf intervention across time. Our work suggests that isolated measurements do not show the complete picture of the modulatory effects of oral bLf in immunological sites as dynamic as the proximal small intestine.
Asunto(s)
Inmunidad Mucosa/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Intestino Delgado/efectos de los fármacos , Lactoferrina/administración & dosificación , Ganglios Linfáticos Agregados/efectos de los fármacos , Linfocitos T Colaboradores-Inductores/efectos de los fármacos , Administración Oral , Animales , Citocinas/metabolismo , Inmunoglobulina A/metabolismo , Inmunoglobulina M/metabolismo , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Intestino Delgado/inmunología , Intestino Delgado/metabolismo , Masculino , Ratones Endogámicos BALB C , Ganglios Linfáticos Agregados/inmunología , Ganglios Linfáticos Agregados/metabolismo , Fenotipo , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo , Factores de Tiempo , Factor de Crecimiento Transformador beta/metabolismoRESUMEN
We previously conducted two randomized controlled trials with bovine lactoferrin (bLF) for the prevention of late-onset sepsis (LOS) in infants with a birth weight <2500 g (Study 1) and <2000 g (Study 2). The aim of this study was to determine the preventative effects of bLF on culture-proven or probable LOS in infants with a birth weight <1500 g from both studies, and to determine the effect of bLF in relation to intake of human milk. Both trial designs had similar inclusion and exclusion criteria, the same dose of bLF [200 mg·(kg body mass)-1·day-1], and used the same control (maltodextrin). We fitted multivariate Cox regression models to estimate the effect of bLF on the risk of development of the composite outcome, adjusting for covariates. We included 335 neonates with a mean birth weight of 1162 ± 244 g; 27.5% were <1000 g. There were 33 first episodes of LOS in the bLF treatment group and 48 in the control group (19.5% vs. 28.9%). bLF had a protective effect on the risk of development of LOS [hazard ratio (HR) = 0.64; %95 CI = 0.41-0.99; p = 0.048]; particularly among infants weighing <1000 g [HR = 0.46; %95 CI = 0.22-0.96; p = 0.039] and infants with a low intake of human milk [HR = 0.40; %95 CI = 0.19-0.84; p = 0.015]. Therefore, bLF supplementation protects infants <1500 g from LOS, particularly those infants not receiving human milk.
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Lactoferrina/administración & dosificación , Sepsis/prevención & control , Animales , Bovinos , Humanos , Recién Nacido , Recien Nacido Prematuro , Leche Humana/química , Proyectos PilotoRESUMEN
Introducción. Los probióticos y prebióticos presentan beneficios potenciales en la inflamacióncrónica de las mucosas, incluida la prevención de la enterocolitis necrosante. No obstante, los mecanismos y resultados de estos efectos inmunomoduladores son confusos. El objetivo fue investigar la respuesta de las citocinas a Lactobacillus y Bifidobacterium asociados con fructo- y galactooligosacáridos (simbióticos) y lactoferrina en recién nacidos de muy bajo peso al nacer.Población y métodos. Se asignó aleatoriamente a lactantes con ≤32 semanas de gestación y ≤1500 g de peso para recibir simbióticos o 1 ml de agua destilada como placebo desde la primera alimentación hasta el alta. Se obtuvieron muestras de sangre los días posnatales 0 ± 2, 14 ± 2 y 28 ± 2, y se midieron interferón-γ, interleucina (IL)-5, IL-10 e IL-17A.Resultados. En el grupo del estudio (n = 25), la concentración de IL-10 disminuyó a lo largo del estudio (p = 0,011), pero no cambió en el grupo de referencia. La concentración de IL-5 se mantuvo constante los primeros 14 días y luego disminuyó significativamente (p= 0,042) en el grupo del estudio, mientras que aumentó en los primeros 14 días (p = 0,019) y luego disminuyó en 28 días (p = 0,011) en el grupo de referencia (n = 25).La concentración de otras citocinas no cambió a lo largo del estudio.Conclusión. El uso combinado de probióticos con oligosacáridos y lactoferrina estuvo asociado con una disminución en la concentración de IL-10, pero no se observó un cambio en las otras citocinas.
Introduction. Probiotics and prebiotics, which are multifunctional agents, have potential benefits in chronic mucosal inflammation, including the prevention of necrotizing enterocolitis. However, the mechanisms and the results of these immunomodulatory effects are not clear. This study aimed to investigate the cytokine response to the combination of Lactobacillus and Bifidobacterium together with fructo- and galacto-oligosaccharides (symbiotic) and lactoferrin in very low birth weight neonates.Population and Methods. Infants ≤ 32 GWs and ≤ 1,500 g were randomly assigned to receive a symbiotic combination or 1 ml distilled water as placebo starting with the first feed until discharge. Blood samples were obtained at postnatal 0 ± 2, 14 ± 2, and 28 ± 2 days, and the serum levels of interferon-γ, interleukin (IL)-5, IL-10, and IL-17A were measured.Results. In the study group (n = 25), the IL-10 levels decreased throughout the study period (p = 0.011) but did not change in the control group. The IL-5 levels remained steady in the first 14 days and decreased significantly thereafter (p = 0.042) in the study group, whereas they increased in the first 14 days (p = 0.019), and then decreased in 28 days (p = 0.011) in the control group (n = 25). The levels of the other cytokines did not change throughout the study period.Conclusion.The combined use of probiotics with oligosaccharides and lactoferrin was associated with a decrease in IL-10 levels, but no change was observed in the other cytokines.
Asunto(s)
Humanos , Masculino , Femenino , Recién Nacido , Citocinas/análisis , Probióticos/uso terapéutico , Prebióticos , Simbióticos/administración & dosificación , Lactoferrina/administración & dosificación , Oligosacáridos/uso terapéutico , Turquía , Estudios Prospectivos , Citocinas/sangre , Recién Nacido de muy Bajo Peso , Enterocolitis Necrotizante/prevención & control , Leche HumanaRESUMEN
OBJECTIVE: To investigate whether exposure to inhibitors of gastric acidity, such as H2 blockers or proton pump inhibitors, can independently increase the risk of infections in very low birth weight (VLBW) preterm infants in the neonatal intensive care unit. STUDY DESIGN: This is a secondary analysis of prospectively collected data from a multicenter, randomized controlled trial of bovine lactoferrin (BLF) supplementation (with or without the probiotic Lactobacillus rhamnosus GG) vs placebo in prevention of late-onset sepsis (LOS) and necrotizing enterocolitis (NEC) in preterm infants. Inhibitors of gastric acidity were used at the recommended dosages/schedules based on the clinical judgment of attending physicians. The distribution of days of inhibitors of gastric acidity exposure between infants with and without LOS/NEC was assessed. The mutually adjusted effects of birth weight, gestational age, duration of inhibitors of gastric acidity treatment, and exposure to BLF were controlled through multivariable logistic regression. Interaction between inhibitors of gastric acidity and BLF was tested; the effects of any day of inhibitors of gastric acidity exposure were then computed for BLF-treated vs -untreated infants. RESULTS: Two hundred thirty-five of 743 infants underwent treatment with inhibitors of gastric acidity, and 86 LOS episodes occurred. After multivariate analysis, exposure to inhibitors of gastric acidity remained significantly and independently associated with LOS (OR, 1.03; 95% CI, 1.008-1.067; P = .01); each day of inhibitors of gastric acidity exposure conferred an additional 3.7% odds of developing LOS. Risk was significant for Gram-negative (P < .001) and fungal (P = .001) pathogens, but not for Gram-positive pathogens (P = .97). On the test for interaction, 1 additional day of exposure to inhibitors of gastric acidity conferred an additional 7.7% risk for LOS (P = .003) in BLF-untreated infants, compared with 1.2% (P = .58) in BLF-treated infants. CONCLUSION: Exposure to inhibitors of gastric acidity is significantly associated with the occurrence of LOS in preterm VLBW infants. Concomitant administration of BLF counteracts this selective disadvantage. TRIAL REGISTRATION: isrctn.org: ISRCTN53107700.
Asunto(s)
Enterocolitis Necrotizante/prevención & control , Antagonistas de los Receptores H2 de la Histamina/efectos adversos , Lactoferrina/administración & dosificación , Probióticos/administración & dosificación , Inhibidores de la Bomba de Protones/efectos adversos , Sepsis/prevención & control , Administración Oral , Suplementos Dietéticos , Enterocolitis Necrotizante/epidemiología , Ácido Gástrico , Humanos , Recién Nacido , Recien Nacido Prematuro , Recién Nacido de muy Bajo Peso , Unidades de Cuidado Intensivo Neonatal , Italia , Lacticaseibacillus rhamnosus , Nueva Zelanda , Factores de Riesgo , Sepsis/epidemiologíaRESUMEN
Oral squamous cell carcinoma is the fifth most common epithelial cancer in the world, and its current clinical treatment has both low efficiency and poor selectivity. Cationic amphipathic peptides have been proposed as new drugs for the treatment of different types of cancer. The main goal of the present work was to determine the potential of LfcinB(20-25)4, a tetrameric peptide based on the core sequence RRWQWR of bovine lactoferricin LfcinB(20-25), for the treatment of OSCC. In brief, OSCC was induced in the buccal pouch of hamsters by applying 7,12-Dimethylbenz(a)anthracene, and tumors were treated with one of the following peptides: LfcinB(20-25)4, LfcinB(20-25), or vehicle (control). Lesions were macroscopically evaluated every two days and both histological and serum IgG assessments were conducted after 5 weeks. The size of the tumors treated with LfcinB(20-25)4 and LfcinB(20-25) was smaller than that of the control group (46.16±4.41 and 33.92±2.74 mm3 versus 88.77±10.61 mm3, respectively). Also, LfcinB(20-25)4 caused acellularity in the parenchymal tumor compared with LfcinB(20-25) and vehicle treatments. Furthermore, our results demonstrated that both LfcinB(20-25)4 and LfcinB(20-25) induced higher degree of apoptosis relative to the untreated tumors (75-86% vs 8%, respectively). Moreover, although the lowest inflammatory response was achieved when LfcinB(20-25)4 was used, this peptide appeared to induce higher levels of IgG antibodies relative to the vehicle and LfcinB(20-25). In addition the cellular damage and selectivity of the LfcinB(20-25)4 peptide was evaluated in vitro. These assays showed that LfcinB(20-25)4 triggers a selective necrotic effect in the carcinoma cell line. Cumulatively, these data indicate that LfcinB(20-25)4 could be considered as a new therapeutic agent for the treatment of OSCC.
Asunto(s)
Carcinoma de Células Escamosas/tratamiento farmacológico , Lactoferrina/administración & dosificación , Neoplasias de la Boca/tratamiento farmacológico , Péptidos/administración & dosificación , Animales , Apoptosis/efectos de los fármacos , Carcinoma de Células Escamosas/patología , Bovinos , Proliferación Celular/efectos de los fármacos , Humanos , Células Jurkat , Lactoferrina/química , Neoplasias de la Boca/patología , Péptidos/químicaRESUMEN
Bovine lactoferrin (bLf) up-modulates intestinal IgA that is essential for homeostasis and which might confer protection to the distal small intestine that is vulnerable to inflammation. This study analyzed the effects of bLf administered orally on the IgA response at inductive (Peyer's patches) and effector (lamina propria) sites of the distal small intestine in mice. Groups of five healthy male BALB/c mice were orally treated with 5 mg of bLf for 7, 14, 21, or 28 days. Then, mice were killed and the distal small intestine was dissected. Intestinal fluid samples were analyzed to determine IgA and IgM levels by enzyme-immuno assay. Peyer's patches and lamina propria were analyzed for IgA(+) or IgM(+) plasma cells, B, CD4(+) T and CD8(+) T cells as well as CD4(+) T cells positive for either pro-inflammatory cytokines [tumor necrosis factor (TNF)-α, interferon-γ and interleukin (IL)-12] or for IgA-producing ILs (IL-4, -5, -10 and -6) by cytofluorometry. Antibodies, antibody-secreting cells, and B and T responses in both Peyer's patches and lamina propria were higher in bLf-treated than bLf-untreated mice. The generation of IL-10 and IL-6 CD4(+) T cells in Peyer's patches or TNF-α and IL-12 CD4(+) T cells in lamina propria showed similar response patterns. On days 14 and 28, cytokine/IL CD4(+) T cell responses were increased in Peyer's patches or decreased in lamina propria. The effect of bLf on the elicitation of IgA indicates a potential application of bLf as a nutraceutical to control inflammation in the distal small intestine.
Asunto(s)
Linfocitos B/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Inmunomodulación , Inflamación/inmunología , Intestino Delgado/efectos de los fármacos , Lactoferrina/administración & dosificación , Administración Oral , Animales , Bovinos , Citocinas/metabolismo , Suplementos Dietéticos , Humanos , Inmunidad Humoral/efectos de los fármacos , Inmunoglobulina A/metabolismo , Inflamación/tratamiento farmacológico , Mediadores de Inflamación/metabolismo , Intestino Delgado/inmunología , Lactoferrina/efectos adversos , Masculino , Ratones Endogámicos BALB CRESUMEN
A lactoferrina é uma glicoproteína de ligação ao ferro, que está presente na saliva, no leite, e em outras secreções exócrinas. Essa proteína tem inúmeras funções biológicas, incluindo efeitos antifúngicos e antibacterianos, além de imunomoduladores. O objetivo do presente estudo foi avaliar, in vitro, pela primeira vez, a atividade antifúngica da lactoferrina contra cepas de Candida nãoalbicans isoladas da cavidade oral de crianças infectadas pelo HIV e crianças saudáveis. Além disso, mensurar a degradação da lactoferrina por essas cepas através de SDS-PAGE (análise eletroforética em gel de poliacrilamida) e determinar, in vitro, a concentração mínima inibitória de lactoferrina capaz de matar 50% das células de Candida não-albicans. Cepas de Candida spp. foram obtidas através da coleta de saliva de 70 crianças infectadas pelo HIV e 50 crianças sem evidências de imunossupressão, com idade de 3 a 13 anos (ALVES, 2014). As diferentes espécies de Candida foram identificadas através de assimilação e fermentação de açúcar (API 20Cï¢, Biomérieux, França). Para o ensaio, in vitro, de morte de celular na presença de lactoferrina, 24 isolados de Candida, entre elas parapsilosis, tropicalis, krusei, guillermondi e dubliniensis, foram selecionados. Para a realização da análise por SDS-PAGE, cepas de todas as espécies consideradas resistentes nos ensaios de morte celular, foram incluídas. O porcentual de morte celular (%) de Candida não- albicans com a adição de 100 µg/ml de lactoferrina variou de 3,1% (C. dubliniensis) a 88,1% (C. tropicalis) no grupo HIV, e de 14,1% a 30,37% no grupo não-HIV (C . parapsilosis). Não houve correlação entre a densidade celular e o percentual de morte celular. C. dubliniensis foi a espécie mais resistente a lactoferrina e o porcentual de morte celular de C. parapsilosis foi significativamente maior em comparação com C. krusei na concentração de 1X104 células/ml (p = 0,033). Todos os isolados foram capazes de degradar a lactoferrina na concentração 1x108 células/ml, especialmente C. parapsilosis, pelo grupo HIV. Além disso, a lactoferrina na concentração de 500 µg/ml foi capaz de matar mais de 50% das células apenas dos isolados de C. tropicalis e C. guilliermondii. Concluiu-se que a lactoferrina tem atividade antifúngica contra Candida não-albicans de crianças infectadas pelo HIV, mas algumas espécies apresentam alguma resistência a esta proteína. Além disso, todas as Candida spp. foram capazes de degradar a lactoferrina quando estavam em concentração de 1X108 cels/ml, e a lactoferrina na concentração de 500µl/ml foi capaz de matar mais que 50% das células de C. tropicalis e C. guillermondii
Lactoferrin is an iron-binding glycoprotein, which is present in saliva, milk and other exocrine secretions. This protein has a number of biological functions, including antifungical, antimicrobial and immunomodulatory effects. The aim of this study was to evaluate, for the first time, the antifungal activity of lactoferrin against isolates of Candida spp. from the oral cavity of HIV-infected children and children with no clinical evidence of immunosuppression. Furthermore, measure, in vitro, the degradation of lactoferrin by Candida spp. through SDS-PAGE (electrophoretic analysis on polyacrylamide gel) and determine, in vitro, the minimum inhibitory concentration of lactoferrin able to kill 50% of cells of Candida non-albicans. Strains of Candida spp. were obtained through saliva collect of 70 HIV-infected children and 50 children without evidence of immunosuppression ageing between 3 to13 years old (ALVES, 2014). All Candida species were identified by sugar assimilation and fermentation (API 20Cï¢, Biomerieux, France). For the in vitro study, death of lactoferrin of 24 Candida isolates, including parapsilosis, tropicalis, krusei, guillermondii, and dubliniensis, were selected. To perform the analysis by SDS-PAGE, strains of all available species considered resistants, which were observed at lactoferrin death`s study, were included. The cell death percentage (%) of non-albicans Candida by addition of 100 µg of lactoferrin range from 3.1% (C. dublinienes) to 88.1% (C. tropicalis) in HIV group, and 14.1% to 30.37% in N-HIV (C. parapsilosis), but there was no correlation between cell density and death %. C. dubliniensis was the most resistant specie to lactoferrin and the cell death % of C. parapsilosis was significant higher comparing to C. krusei at 1X104 cells/ml (p=0.033). All the isolates were able to degrade lactoferrin at 108 cells/ml, mainly C. parapsilosis from HIV. Furthermore, lactoferrin at 500 µg/ml concentration was able to kill more than 50% of the cells only for C. tropicalis and C. guillermondii isolates. It was concluded that lactoferrin has antifungal activity against non-albicans Candida from HIV children, but some species present some resistance to this protein. Furthermore, all Candida spp. were able to degrade lactoferrin when was at concentration of 1x108 cells / ml, also, lactoferrin at concentration 500µl / ml was able to kill more than 50% of C. tropicalis and C. guillermondii cells.
Asunto(s)
Humanos , Niño , Antifúngicos/farmacología , Candida/efectos de los fármacos , VIH , Lactoferrina/administración & dosificación , Candida/aislamiento & purificación , Estudios de Casos y Controles , Lactoferrina/farmacología , SalivaRESUMEN
BACKGROUND: Lactoferrin (LF) is a broad-spectrum antimicrobial and immunomodulatory milk glycoprotein. OBJECTIVE: To determine the effect of bovine LF on the prevention of the first episode of late-onset sepsis in Peruvian infants. METHODS: We conducted a pilot randomized placebo-controlled double blind study in infants with a birth weight (BW) less than 2500g in 3 Neonatal Units in Lima. Patients were randomized to receive bovine LF 200mg/kg/d or placebo for 4 weeks. RESULTS: One hundred and ninety neonates with a BW of 1591 ± 408 g and a gestational age of 32.1 ± 2.6 weeks were enrolled. Overall, 33 clinically defined first late-onset sepsis events occurred. The cumulative sepsis incidence in the LF group was 12/95 (12.6%) versus 21/95 (22.1%) in the placebo group, and 20% (8/40) versus 37.5% (15/40) for infants less than or equal to 1500 g. The hazard ratio of LF, after adjustment by BW, was 0.507 (95% CI: 0.249-1.034). There were 4 episodes of culture-proven sepsis in the LF group versus 4 in the placebo group. Considering that children did not received the intervention until the start of oral or tube feeding, we ran a secondary exploratory analysis using time since the start of the treatment; in this model, LF achieved significance. There were no serious adverse events attributable to the intervention. CONCLUSIONS: Overall sepsis occurred less frequently in the LF group than in the control group. Although the primary outcome did not reach statistical significance, the confidence interval is suggestive of an effect that justifies a larger trial.
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Antiinfecciosos/administración & dosificación , Factores Inmunológicos/administración & dosificación , Lactoferrina/administración & dosificación , Sepsis/prevención & control , Método Doble Ciego , Humanos , Recién Nacido , Perú , Proyectos Piloto , Placebos/administración & dosificación , Resultado del TratamientoRESUMEN
Actinobacillus pleuropneumoniae (App) is a Gram-negative bacterium that causes porcine pleuropneumonia, leading to economic losses in the swine industry. Due to bacterial resistance to antibiotics, new treatments for this disease are currently being sought. Lactoferrin (Lf) is an innate immune system glycoprotein of mammals that is microbiostatic and microbicidal and affects several bacterial virulence factors. The aim of this study was to investigate whether bovine iron-free Lf (BapoLf) has an effect on the growth and virulence of App. Two serotype 1 strains (reference strain S4074 and the isolate BC52) and a serotype 7 reference strain (WF83) were analyzed. First, the ability of App to grow in iron-charged BLf was discarded because in vivo, BapoLf sequesters iron and could be a potential source of this element favoring the infection. The minimum inhibitory concentration of BapoLf was 14.62, 11.78 and 10.56 µM for the strain BC52, S4074 and WF83, respectively. A subinhibitory concentration (0.8 µM) was tested by assessing App adhesion to porcine buccal epithelial cells, biofilm production, and the secretion and function of toxins and proteases. Decrease in adhesion (24-42 %) was found in the serotype 1 strains. Biofilm production decreased (27 %) for only the strain 4074 of serotype 1. Interestingly, biofilm was decreased (60-70 %) in the three strains by BholoLf. Hemolysis of erythrocytes and toxicity towards HeLa cells were not affected by BapoLf. In contrast, proteolytic activity in all strains was suppressed in the presence of BapoLf. Finally, oxytetracycline produced synergistic effect with BapoLf against App. Our results suggest that BapoLf affects the growth and several of the virulence factors in App.
Asunto(s)
Actinobacillus pleuropneumoniae/crecimiento & desarrollo , Actinobacillus pleuropneumoniae/patogenicidad , Apoproteínas/fisiología , Lactoferrina/fisiología , Infecciones por Actinobacillus/etiología , Infecciones por Actinobacillus/veterinaria , Actinobacillus pleuropneumoniae/fisiología , Animales , Antibacterianos/administración & dosificación , Péptidos Catiónicos Antimicrobianos/administración & dosificación , Péptidos Catiónicos Antimicrobianos/inmunología , Péptidos Catiónicos Antimicrobianos/fisiología , Apoproteínas/administración & dosificación , Apoproteínas/inmunología , Adhesión Bacteriana , Toxinas Bacterianas/biosíntesis , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Bovinos , Sinergismo Farmacológico , Células HeLa , Humanos , Hierro/metabolismo , Lactoferrina/administración & dosificación , Lactoferrina/inmunología , Oxitetraciclina/administración & dosificación , Pleuroneumonía/etiología , Pleuroneumonía/veterinaria , Porcinos , Enfermedades de los Porcinos/etiología , VirulenciaRESUMEN
Lactoferrin (Lf) is a multifunctional iron-binding glycoprotein with antibacterial and immunomodulatory activities. The antibacterial influence of orally administered bovine Lf (bLf) against murine infection caused by Salmonella typhimurium (S. typhimurium) has scarcely been explored. In the current study, Balb/c mice were treated orally for 7 days with either 5 or 100mg of bovine lactoferrin (bLf). On day 7 of treatment, mice were intragastrically infected with a lethal or sublethal dose of colony forming units (CFU) of S. typhimurium. During treatment with bLf, feces from mice sublethally infected were harvested daily to prepare fecal suspensions, which were serially diluted and plated onto Salmonella Shigella agar to estimate CFU/g of feces. After sacrificing the animals on day 7, 14 or 21 post-infection, samples of intestinal fluid, Peyer's patches (PP), liver and spleen were collected to count the number of CFU by plate dilution. Intestinal secretions were also employed, along with serum samples, to evaluate total IgA, IgG and IgM antibodies, and those against Salmonella surface proteins and bLf by ELISA assay. In lethally infected mice both bLf doses decreased mortality. In sublethally infected mice, both bLf doses decreased bacterial shedding in feces and intestinal fluid, and also reduced bacterial colonization at PP and bacterial translocation in the liver and spleen. Levels of total and those IgG and IgM in serum and IgA in intestinal secretions against Salmonella surface proteins and bLf were enhanced with both doses of bLf. These findings suggest that the effect of bLf against the infection by S. typhimurium in mice may be the result of an antimicrobial activity linked with its modulatory effect on immunocompetent cells (from intestinal and peripheral organs) involved in antibody production.
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Anticuerpos Antibacterianos/sangre , Lactoferrina/farmacología , Salmonelosis Animal/tratamiento farmacológico , Salmonella typhimurium/efectos de los fármacos , Administración Oral , Animales , Anticuerpos Antibacterianos/inmunología , Carga Bacteriana , Traslocación Bacteriana/efectos de los fármacos , Bovinos , Ensayo de Inmunoadsorción Enzimática , Heces/microbiología , Inmunoglobulina A/sangre , Inmunoglobulina A/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Inmunoglobulina M/sangre , Inmunoglobulina M/inmunología , Intestinos/efectos de los fármacos , Intestinos/microbiología , Lactoferrina/administración & dosificación , Ratones , Ratones Endogámicos BALB C , Salmonelosis Animal/inmunología , Salmonelosis Animal/mortalidad , Salmonella typhimurium/inmunología , Tasa de Supervivencia , Factores de TiempoRESUMEN
We conducted a randomized, double-blind, placebo-controlled trial comparing supplementation with bovine lactoferrin versus placebo for the prevention of diarrhea in children. Comparison of overall diarrhea incidence and prevalence rates found no significant difference between the 2 groups. However, there was a lower prevalence of colonization with Giardia species and better growth among children in the lactoferrin group.
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Diarrea/prevención & control , Suplementos Dietéticos , Giardia/aislamiento & purificación , Giardiasis/prevención & control , Lactoferrina/administración & dosificación , Animales , Preescolar , Heces/microbiología , Heces/parasitología , Humanos , Lactante , Placebos/administración & dosificaciónRESUMEN
OBJECTIVE: To compare glucose and rice-based oral rehydration solution with rice-based oral rehydration solution containing recombinant human lactoferrin and recombinant human lysozyme in diarrhea outcomes. PATIENTS AND METHODS: We conducted a randomized, double-blind controlled trial in children with acute diarrhea and dehydration. One hundred and forty children 5 to 33 months old were block randomized to receive low osmolarity WHO-ORS (G-ORS), rice-based ORS (R-ORS), or rice-based ORS plus lactoferrin and lysozyme (Lf/Lz-R-ORS). Intake and output were monitored for 48 h in the ORU, with continued monitoring through home and clinic follow-up for 14 d. RESULTS: The G-ORS and R-ORS groups did not show any differences in diarrhea outcomes and were therefore combined as the control group. Intent-to-treat analysis showed a significant decrease in duration of diarrhea (3.67 d vs 5.21 d, P = 0.05) in the Lf/Lz-R-ORS group as compared with the control group and a significant increase in the number of children who achieved 48 h with solid stool, 85% vs 69% (P < 0.05). There were no significant differences [corrected] in volume of diarrhea or [corrected] the percentage of children who had a new diarrhea episode after achieving the endpoint. CONCLUSIONS: Addition of recombinant human lactoferrin and lysozyme to a rice-based oral rehydration solution had beneficial effects on children with acute diarrhea.