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1.
Nutrients ; 12(7)2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32679677

RESUMEN

Numerous health related properties have been reported for bovine milk fat globule membrane (MFGM) and its components. Here we present novel data on the in vitro and in vivo anti-inflammatory activity of various MFGM preparations which confirm and extend the concept of MFGM as a dietary anti-inflammatory agent. Cell-based assays were used to test the ability of MFGM preparations to modulate levels of the inflammatory mediators IL-1ß, nitric oxide, superoxide anion, cyclo-oxygenase-2, and neutrophil elastase. In rat models of arthritis, using MFGM fractions as dietary interventions, the phospholipid-enriched MFGM isolates were effective in reducing adjuvant-induced paw swelling while there was a tendency for the ganglioside-enriched isolate to reduce carrageenan-induced rat paw oedema. These results indicate that the anti-inflammatory activity of MFGM, rather than residing in a single component, is contributed to by an array of components acting in concert against various inflammatory targets. This confirms the potential of MFGM as a nutritional intervention for the mitigation of chronic and acute inflammatory conditions.


Asunto(s)
Antiinflamatorios , Artritis/terapia , Suplementos Dietéticos , Glucolípidos/administración & dosificación , Glucolípidos/farmacología , Glicoproteínas/administración & dosificación , Glicoproteínas/farmacología , Mediadores de Inflamación/metabolismo , Fenómenos Fisiológicos de la Nutrición/fisiología , Animales , Artritis/metabolismo , Células Cultivadas , Ciclooxigenasa 2/metabolismo , Modelos Animales de Enfermedad , Edema/terapia , Interleucina-1beta/metabolismo , Elastasa de Leucocito/metabolismo , Gotas Lipídicas , Monocitos/metabolismo , Neutrófilos/metabolismo , Óxido Nítrico/metabolismo , Superóxidos/metabolismo
2.
BMC Rheumatol ; 3: 27, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31334482

RESUMEN

BACKGROUND: Methods of gout flare reporting in research settings are inconsistent and poorly defined. The aim of this study was to describe patterns of gout flare and assess the concurrent validity of different methods of flare reporting in a gout clinical trial. METHODS: Daily flare diary entries including self-report of flare and pain scale from a randomised controlled trial of 120 patients with gout were analysed. Detailed pain-by-time plots for each participant were inspected and analysed for different methods of flare reporting for both self-report and the classification tree (CART)-defined flare developed by Gaffo in 2012. Concurrent validity for different methods of flare reporting were analysed. RESULTS: Although the single gout flare had a 'typical' average pattern (peak on day 1 and resolution over 14 days), individual pain-by-time plots showed wide variation in pain intensity, duration and frequency of flares. Over the four-month study period, there were 84/120 (70%) participants who experienced at least one self-reported flare that was not a 'typical' flare. The time to first self-reported flare correlated poorly with other measures of gout activity and other methods of flare reporting. The number of days with flare (either self-reported or Gaffo-defined) and the area under the pain-by-time curve correlated most strongly with other measures of disease severity. CONCLUSION: There is wide variation in the patterns of flare over time in individuals with gout, leading to challenges for flare reporting in clinical trials. Time-dependent reporting strategies such as number of days with flare or area under the pain-by-time curve correlate well with other measures of gout disease severity and may provide a more accurate measure of flare burden. TRIAL REGISTRATION: Clinical trial number: ACTRN12609000479202, registered 17/06/2009.

3.
Nutrients ; 7(5): 3891-913, 2015 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-26007338

RESUMEN

Gangliosides are important components of neuronal cell membranes and it is widely accepted that they play a critical role in neuronal and brain development. They are functionally involved in neurotransmission and are thought to support the formation and stabilization of functional synapses and neural circuits required as the structural basis of memory and learning. Available evidence, as reviewed herein, suggests that dietary gangliosides may impact positively on cognitive functions, particularly in the early postnatal period when the brain is still growing. Further, new evidence suggests that the mechanism of action may be through an effect on the neuroplasticity of the brain, mediated through enhanced synaptic plasticity in the hippocampus and nigro-striatal dopaminergic pathway.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Cognición/fisiología , Dieta , Gangliósidos/metabolismo , Memoria , Plasticidad Neuronal , Sinapsis/metabolismo , Animales , Dopamina/metabolismo , Humanos , Lactante , Fórmulas Infantiles
4.
J Pediatr Gastroenterol Nutr ; 59(2): 167-71, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25023444

RESUMEN

Rotavirus (RV) is a leading cause of morbidity and mortality in children younger than 5 years of age, presenting commonly with diarrhoeal symptoms. In a prospective 12-week double-blind randomised controlled trial we assessed acceptability and efficacy of a high-ganglioside complex milk lipid (CML) for prevention of RV infection in 450 infants, ages 8 to 24 months, at 3 sites in northern India. Prevalence of diarrhoea and RV was unseasonably low at baseline (all-cause diarrhoea [ACD], n = 16; RV diarrhoea [RVD], n = 2; RV infection, RV positive [RV+], n = 20) and throughout the trial, with only 110 total episodes of ACD for 12 weeks (CML, n = 62; control, n = 48) of which 10 were RVD (CML, n = 4; control, n = 6). Mean duration that RVD persisted was lower in the CML group (2.3 ±â€Š0.5 days) than that in the control group (3.8 ±â€Š1.3 days, P = 0.03), but only 3 of 450 end of trial stool samples were identified as RV+ (<1%; CML, n = 2; control, n = 1). This hampered the assessment of efficacy of CML, despite the large a priori determined sample size. During the trial similar numbers of infants reported adverse events (AEs: CML 41%, control 46%), with the majority of events classified as mild and not related to the intervention. In conclusion, further clinical trials against a higher background of seasonal prevalence are necessary to assess efficacy of this nutritional intervention to prevent RVD. More important, however, high-ganglioside CML was acceptable for long-term consumption in infants ages 8 to 24 months.


Asunto(s)
Diarrea/prevención & control , Gangliósidos/uso terapéutico , Leche/química , Infecciones por Rotavirus/prevención & control , Rotavirus , Animales , Bovinos , Preescolar , Diarrea/etiología , Diarrea/virología , Método Doble Ciego , Heces/virología , Femenino , Gangliósidos/efectos adversos , Humanos , India , Lactante , Masculino , Prevalencia , Estudios Prospectivos , Infecciones por Rotavirus/complicaciones , Infecciones por Rotavirus/virología , Estaciones del Año , Resultado del Tratamiento , Adulto Joven
5.
BMC Cancer ; 12: 591, 2012 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-23231648

RESUMEN

BACKGROUND: Tamoxifen is used in hormone therapy for estrogen-receptor (ER)-positive breast cancer, but also has chemopreventative effects against ER-negative breast cancers. This study sought to investigate whether oral iron-saturated bovine lactoferrin (Fe-Lf), a natural product which enhances chemotherapy, could improve the chemotherapeutic effects of tamoxifen in the treatment of ER-negative breast cancers. METHODS: In a model of breast cancer prevention, female Balb/c mice treated with tamoxifen (5 mg/Kg) were fed an Fe-Lf supplemented diet (5 g/Kg diet) or the base diet. At week 2, 4T1 mammary carcinoma cells were injected into an inguinal mammary fat pad. In a model of breast cancer treatment, tamoxifen treatment was not started until two weeks following tumor cell injection. Tumor growth, metastasis, body weight, and levels of interleukin 18 (IL-18) and interferon γ (IFN-γ) were analyzed. RESULTS: Tamoxifen weakly (IC(50) ~ 8 µM) inhibited the proliferation of 4T1 cells at pharmacological concentrations in vitro. In the tumor prevention study, a Fe-Lf diet in combination with tamoxifen caused a 4 day delay in tumor formation, and significantly inhibited tumor growth and metastasis to the liver and lung by 48, 58, and 66% (all P < 0.001), respectively, compared to untreated controls. The combination therapy was significantly (all P < 0.05) more effective than the respective monotherapies. Oral Fe-Lf attenuated the loss of body weight caused by tamoxifen and cancer cachexia. It prevented tamoxifen-induced reductions in serum levels of IL-18 and IFN-γ, and intestinal cells expressing IL-18 and IFN-γ. It increased the levels of Lf in leukocytes residing in gut-associated lymphoid tissues. B, T and Natural killer (NK) cells containing high levels of Lf were identified in 4T1 tumors, suggesting they had migrated from the intestine. Similar effects of Fe-Lf and tamoxifen on tumor cell viability were seen in the treatment of established tumors. CONCLUSIONS: The results indicate that Fe-Lf is a potent natural adjuvant capable of augmenting the chemotherapeutic activity of tamoxifen. It could have application in delaying relapse in tamoxifen-treated breast cancer patients who are at risk of developing ER-negative tumors.


Asunto(s)
Antineoplásicos Hormonales/farmacología , Lactoferrina/farmacología , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Tamoxifeno/farmacología , Animales , Bovinos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Suplementos Dietéticos , Ensayo de Inmunoadsorción Enzimática , Femenino , Inmunohistoquímica , Hierro/farmacología , Neoplasias Mamarias Experimentales/patología , Ratones , Ratones Endogámicos BALB C , Trasplante de Neoplasias
6.
Ann Rheum Dis ; 71(6): 929-34, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22275296

RESUMEN

OBJECTIVES: Previous laboratory studies have identified two dairy fractions, glycomacropeptide (GMP) and G600 milk fat extract (G600), with anti-inflammatory effects in models of acute gout. The aim of this proof-of-concept clinical trial was to test the hypothesis that daily intake of skim milk powder (SMP) enriched with GMP and G600 can prevent gout flares. METHODS: This was a 3-month randomised double-blind controlled trial of milk products for prevention of gout flares. One hundred and twenty patients with recurrent gout flares were randomised to one of three arms: lactose powder control, SMP control and SMP enriched with GMP and G600 (SMP/GMP/G600). The primary end point was change in the frequency of gout flares using a daily flare diary measured monthly for 3 months. RESULTS: The frequency of gout flares reduced in all three groups over the 3-month study period compared with baseline. Over the 3-month study period there was a significantly greater reduction in gout flares in the SMP/GMP/G600 group (analysis of covariance p(group)=0.031, Tukey post hoc test compared with lactose control, p=0.044). Following treatment with SMP/GMP/G600 over the 3-month period, greater improvements were also observed in pain and fractional excretion of uric acid, with trends to greater improvement in tender joint count. Similar adverse event rates and discontinuation rates were observed between the three groups. CONCLUSIONS: This is the first reported controlled trial of dietary intervention in patients with gout, and suggests that SMP enriched with GMP and G600 may reduce the frequency of gout flares.


Asunto(s)
Caseínas/administración & dosificación , Productos Lácteos , Glucolípidos/administración & dosificación , Glicoproteínas/administración & dosificación , Gota/dietoterapia , Gota/prevención & control , Proteínas de la Leche/administración & dosificación , Fragmentos de Péptidos/administración & dosificación , Enfermedad Aguda , Adulto , Anciano , Antiinflamatorios/administración & dosificación , Caseínas/efectos adversos , Productos Lácteos/efectos adversos , Femenino , Alimentos Fortificados/efectos adversos , Glucolípidos/efectos adversos , Glicoproteínas/efectos adversos , Gota/inmunología , Humanos , Gotas Lipídicas , Masculino , Persona de Mediana Edad , Proteínas de la Leche/efectos adversos , Fragmentos de Péptidos/efectos adversos , Polvos , Prevención Secundaria , Resultado del Tratamiento
7.
Curr Rheumatol Rep ; 13(2): 132-7, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21188562

RESUMEN

Dietary modification is frequently recommended for patients with gout. Longitudinal observational studies have shown a clear inverse relationship between low-fat dairy intake and gout risk. Several checkpoints in gout pathogenesis may be targeted by dairy intake. Cross-sectional and short-term intervention studies of healthy volunteers have demonstrated that low-fat dairy intake has a moderate urate-lowering effect. In addition, certain dairy fractions, particularly glyco-macropeptide and G600 milk fat extract, have anti-inflammatory properties in experimental models of acute gout. Such anti-inflammatory properties may contribute to the reduction in gout risk through inhibition of the inflammatory response to monosodium urate crystals within the joint. Well-controlled intervention studies in patients with gout are now needed to determine the clinical relevance of these observations in order to guide dietary recommendations for this disease.


Asunto(s)
Productos Lácteos , Supresores de la Gota/administración & dosificación , Gota/dietoterapia , Hiperuricemia/dietoterapia , Antiinflamatorios no Esteroideos/administración & dosificación , Caseínas/administración & dosificación , Estudios Transversales , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Humanos , Fragmentos de Péptidos/administración & dosificación
8.
Ann Rheum Dis ; 69(9): 1677-82, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20472590

RESUMEN

OBJECTIVES: Recent observational studies have highlighted the beneficial role of dairy ingestion in gout prevention. The aims of this study were to determine the acute effects of milk ingestion on serum urate concentrations and examine the mechanisms of these effects. METHODS: This was a short-term randomised controlled crossover trial of milk in 16 healthy male volunteers. The following products were tested (each 80 g protein): soy control, early season skim milk, late season skim milk (containing high concentrations of orotic acid, a naturally occurring uricosuric agent) and ultrafiltrated MPC 85 skim milk. Each participant received a single dose of each product in random order. Serum and urine were obtained immediately before and then hourly over a 3 h period after ingestion of each study product. RESULTS: Ingestion of the soy control led to an increase in serum urate concentrations by approximately 10%. In contrast, ingestion of all milks led to a decrease in serum urate concentrations by approximately 10% (p<0.0001). All products (including soy) rapidly increased the fractional excretion of uric acid (FEUA). Late season milk led to a greater increase in FEUA than MPC 85 (p=0.02) and early season milk (p=0.052). There were no differences over time in serum oxypurines or purine-containing nucleosides. However, all products increased the fractional excretion of xanthine. CONCLUSIONS: Intact milk has an acute urate-lowering effect. These data provide further rationale for long-term intervention studies to determine whether such dietary interventions have an adjunctive role in the management of individuals with hyperuricaemia and gout.


Asunto(s)
Gota/prevención & control , Leche , Ácido Úrico/sangre , Adulto , Animales , Estudios Cruzados , Humanos , Hipoxantina/sangre , Masculino , Persona de Mediana Edad , Leche/efectos adversos , Leche/química , Nucleósidos de Purina/sangre , Estaciones del Año , Leche de Soja/química , Urea/sangre , Xantina/sangre , Adulto Joven
9.
Ann Rheum Dis ; 69(4): 766-9, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19713204

RESUMEN

AIMS: Large epidemiological studies have shown that low-fat dairy intake reduces the risk of developing gout. It was hypothesised that factors within dairy fractions inhibit the inflammatory response to monosodium urate monohydrate (MSU) crystals. METHODS: Dairy fractions were tested in MSU crystal-stimulated THP-1 cell assays. Fractions with inhibitory effects were then tested in the murine urate peritonitis model. RESULTS: Two dairy fractions were found to have consistent inhibitory effects. Glycomacropeptide (GMP) and G600 milk fat extract both inhibited interleukin-1beta (IL1beta) gene and protein expression in the THP-1 cell assay. Conversely, standard milk fat increased IL8 protein expression in the THP-1 cell assay. Oral administration of GMP and G600 milk fat extract inhibited cellular influx in the urate peritonitis model. CONCLUSIONS: Both protein and lipid fractions within dairy products are capable of modulating the inflammatory response to MSU crystals.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Productos Lácteos/análisis , Grasas de la Dieta/uso terapéutico , Proteínas en la Dieta/uso terapéutico , Gota/tratamiento farmacológico , Enfermedad Aguda , Animales , Antiinflamatorios no Esteroideos/farmacología , Caseínas/farmacología , Caseínas/uso terapéutico , Cristalización , Grasas de la Dieta/farmacología , Proteínas en la Dieta/farmacología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos/métodos , Gota/patología , Humanos , Masculino , Ratones , Fragmentos de Péptidos/farmacología , Fragmentos de Péptidos/uso terapéutico , Células Tumorales Cultivadas , Ácido Úrico/antagonistas & inhibidores , Ácido Úrico/farmacología
10.
Immunol Cell Biol ; 86(3): 277-88, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18268518

RESUMEN

Bovine lactoferrin (bLf), an iron-containing natural defence protein found in bodily secretions, has been reported to inhibit carcinogenesis and the growth of tumours. Here, we investigated whether natural bLf and iron-saturated forms of bLf differ in their ability to augment cancer chemotherapy. bLf was supplemented into the diet of C57BL/6 mice that were subsequently challenged subcutaneously with tumour cells, and treated by chemotherapy. Chemotherapy eradicated large (0.6 cm diameter) EL-4 lymphomas in mice that had been fed iron-saturated bLf (here designated Lf(+)) for 6 weeks prior to chemotherapy, but surprisingly not in mice that were fed lesser iron-saturated forms of bLf, including apo-bLf (4% iron saturated), natural bLf (approximately 15% iron saturated) and 50% iron-saturated bLf. Lf(+)-fed mice bearing either EL-4, Lewis lung carcinoma or B16 melanoma tumours completely rejected their tumours within 3 weeks following a single injection of either paclitaxel, doxorubicin, epirubicin or fluorouracil, whereas mice fed the control diet were resistant to chemotherapy. Lf(+) had to be fed to mice for more than 2 weeks prior to chemotherapy to be wholly effective in eradicating tumours from all mice, suggesting that it acts as a competence factor. It significantly reduced tumour vascularity and blood flow, and increased antitumour cytotoxicity, tumour apoptosis and the infiltration of tumours by leukocytes. Lf(+) bound to the intestinal epithelium and was preferentially taken up within Peyer's patches. It increased the production of Th1 and Th2 cytokines within the intestine and tumour, including TNF, IFN-gamma, as well as nitric oxide that have been reported to sensitize tumours to chemotherapy. Importantly, it restored both red and white peripheral blood cell numbers depleted by chemotherapy, potentially fortifying the mice against cancer. In summary, bLf is a potent natural adjuvant and fortifying agent for augmenting cancer chemotherapy, but needs to be saturated with iron to be effective.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carcinoma Pulmonar de Lewis/tratamiento farmacológico , Lactoferrina/administración & dosificación , Linfoma/tratamiento farmacológico , Melanoma Experimental/tratamiento farmacológico , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Farmacéuticos/administración & dosificación , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/inmunología , Carcinoma Pulmonar de Lewis/irrigación sanguínea , Carcinoma Pulmonar de Lewis/dietoterapia , Carcinoma Pulmonar de Lewis/inmunología , Bovinos , Citotoxicidad Inmunológica/efectos de los fármacos , Suplementos Dietéticos , Resistencia a Antineoplásicos/efectos de los fármacos , Inmunohistoquímica , Hierro/química , Lactoferrina/química , Lactoferrina/inmunología , Linfoma/dietoterapia , Linfoma/inmunología , Melanoma Experimental/irrigación sanguínea , Melanoma Experimental/dietoterapia , Melanoma Experimental/inmunología , Ratones , Ratones Endogámicos C57BL , Trasplante de Neoplasias , Neovascularización Patológica/tratamiento farmacológico
11.
Br J Nutr ; 94(2): 244-52, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16115359

RESUMEN

Bovine milk has been shown to contain bioactive components with bone-protective properties. Earlier studies on bovine milk whey protein showed that it suppressed bone resorption in the female ovariectomised rat. A new osteotropic component was subsequently identified in the whey basic protein fraction, but bone bioactivity may also be associated with other whey fractions. In the present study, we investigated whether acidic protein fractions isolated from bovine milk whey could prevent bone loss in mature ovariectomised female rats. Six-month-old female rats were ovariectomised (OVX) or left intact (sham). The OVX rats were randomised into four groups. One group remained the control (OVX), whereas three groups were fed various whey acidic protein fractions from milk whey as 3 g/kg diet for 4 months. Outcomes were bone mineral density, bone biomechanics and markers of bone turnover. Bone mineral density of the femurs indicated that one of the whey AF over time caused a recovery of bone lost from OVX. Plasma C-telopeptide of type I collagen decreased significantly in all groups except OVX control over time, indicating an anti-resorptive effect of whey acidic protein. Biomechanical data showed that the AF may affect bone architecture as elasticity was increased by one of the whey AF. The femurs of AF-supplemented rats all showed an increase in organic matter. This is the first report of an acidic whey protein fraction isolated from milk whey that may support the recovery of bone loss in vivo.


Asunto(s)
Resorción Ósea/prevención & control , Suplementos Dietéticos , Proteínas de la Leche/administración & dosificación , Osteoporosis/prevención & control , Animales , Biomarcadores/análisis , Fenómenos Biomecánicos , Peso Corporal/fisiología , Densidad Ósea/fisiología , Resorción Ósea/fisiopatología , Femenino , Fémur/fisiopatología , Vértebras Lumbares/fisiopatología , Tamaño de los Órganos/fisiología , Osteocalcina/análisis , Osteoporosis/fisiopatología , Ovariectomía/métodos , Inhibidores de Proteasas/administración & dosificación , Ratas , Ratas Sprague-Dawley , Útero/fisiopatología
12.
Mol Endocrinol ; 18(9): 2268-78, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15178744

RESUMEN

Lactoferrin induces osteoblast proliferation and survival in vitro and is anabolic to bone in vivo. The molecular mechanisms by which lactoferrin exerts these biological actions are not known, but lactoferrin is known to bind to two members of the low-density lipoprotein receptor family, low- density lipoprotein receptor-related proteins 1 (LRP1) and 2 (LRP2). We have examined the role(s) of these receptors in the actions of lactoferrin on osteoblasts. We show that lactoferrin binds to cultured osteoblastic cells, and that LRP1 and LRP2 are expressed in several osteoblastic cell types. In primary rat osteoblastic cells, the LRP1/2 inhibitor receptor associated protein blocks endocytosis of lactoferrin and abrogates lactoferrin-induced p42/44 MAPK signaling and mitogenesis. Lactoferrin-induced mitogenesis is also inhibited by an antibody to LRP1. Lactoferrin also induces receptor associated protein-sensitive activation of p42/44 MAPK signaling and proliferation in osteoblastic human SaOS-2 cells, which express LRP1 but not LRP2. The mitogenic response of LRP1-null fibroblastic cells to lactoferrin is substantially reduced compared with that of cells expressing wild-type LRP1. The endocytic and signaling functions of LRP1 are independent of each other, because lactoferrin can activate mitogenic signaling in conditions in which endocytosis is inhibited. Taken together, these results 1) suggest that mitogenic signaling through LRP1 to p42/44 MAPKs contributes to the anabolic skeletal actions of lactoferrin; 2) demonstrate growth-promoting actions of a third LRP family member in osteoblasts; and 3) provide further evidence that LRP1 functions as a signaling receptor in addition to its recognized role in ligand endocytosis.


Asunto(s)
Endocitosis/fisiología , Lactoferrina/metabolismo , Proteína 1 Relacionada con Receptor de Lipoproteína de Baja Densidad/fisiología , Osteoblastos/metabolismo , Animales , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Activación Enzimática , Fibroblastos/efectos de los fármacos , Expresión Génica , Lactoferrina/análisis , Lactoferrina/farmacología , Proteína 1 Relacionada con Receptor de Lipoproteína de Baja Densidad/genética , Proteína 2 Relacionada con Receptor de Lipoproteína de Baja Densidad/genética , Proteína 2 Relacionada con Receptor de Lipoproteína de Baja Densidad/fisiología , Proteína Quinasa 1 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 1 Activada por Mitógenos/fisiología , Proteína Quinasa 3 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 3 Activada por Mitógenos/fisiología , Mitógenos/metabolismo , Osteoblastos/química , Transporte de Proteínas/fisiología , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Ratas , Transducción de Señal
13.
Endocrinology ; 145(9): 4366-74, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15166119

RESUMEN

Lactoferrin is an iron-binding glycoprotein present in epithelial secretions, such as milk, and in the secondary granules of neutrophils. We found it to be present in fractions of milk protein that stimulated osteoblast growth, so we assessed its effects on bone cell function. Lactoferrin produced large, dose-related increases in thymidine incorporation in primary or cell line cultures of human or rat osteoblast-like cells, at physiological concentrations (1-100 microg/ml). Maximal stimulation was 5-fold above control. Lactoferrin also increased osteoblast differentiation and reduced osteoblast apoptosis by up to 50-70%. Similarly, lactoferrin stimulated proliferation of primary chondrocytes. Purified, recombinant, human, or bovine lactoferrins had similar potencies. In mouse bone marrow cultures, osteoclastogenesis was dose-dependently decreased and was completely arrested by lactoferrin, 100 microg/ml, associated with decreased expression of receptor activator of nuclear factor-kappaB ligand. In contrast, lactoferrin had no effect on bone resorption by isolated mature osteoclasts. Lactoferrin was administered over calvariae of adult mice for 5 d. New bone formation, assessed using fluorochrome labels, was increased 4-fold by a 4-mg dose of lactoferrin. Thus, lactoferrin has powerful anabolic, differentiating, and antiapoptotic effects on osteoblasts and inhibits osteoclastogenesis. Lactoferrin is a potential therapeutic target in bone disorders such as osteoporosis and is possibly an important physiological regulator of bone growth.


Asunto(s)
Lactoferrina/farmacología , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Cartílago/citología , Cartílago/crecimiento & desarrollo , Bovinos , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Condrocitos/citología , Condrocitos/efectos de los fármacos , Cricetinae , Humanos , Riñón/citología , Masculino , Ratones , Leche/química , Leche Humana/química , Técnicas de Cultivo de Órganos , Osteoclastos/citología , Osteoclastos/efectos de los fármacos , Ratas , Cráneo/citología , Cráneo/crecimiento & desarrollo
14.
J Dairy Res ; 69(1): 85-94, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12047114

RESUMEN

Samples of bovine caseinomacropeptide (CMP) were isolated from kappa-casein A and kappa-casein B and fractionated to give aglycosylated CMP A and CMP B and monoglycosylated CMP A. The secondary structures of these three peptides were compared under neutral and acidic (pH 4.2) conditions, using two-dimensional (2D) 1H nuclear magnetic resonance (NMR) spectroscopy. The differences between the spectra at pH 4.2 and 7.0 and the spectra of the aglycosylated and glycosylated CMP A were subtle, indicating little change in backbone conformation with these changes. These results Suggest that differences in the coagulation properties of milks containing either kappa-casein A or kappa-casein B are more likely to be related to factors, such as micelle size or charge, than to structural differences arising from altered backbone conformation of the macropeptide segments of the kappa-caseins.


Asunto(s)
Caseínas/química , Espectroscopía de Resonancia Magnética/métodos , Fragmentos de Péptidos/química , Algoritmos , Secuencia de Aminoácidos , Animales , Caseínas/análisis , Bovinos , Glicosilación , Concentración de Iones de Hidrógeno , Micelas , Proteínas de la Leche/análisis , Conformación Molecular , Datos de Secuencia Molecular , Tamaño de la Partícula , Fragmentos de Péptidos/análisis , Estructura Secundaria de Proteína
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