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1.
Int J Mol Sci ; 23(3)2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35163435

RESUMEN

Lower-extremity arterial disease is a major health problem with increasing prevalence, often leading to non-traumatic amputation, disability and mortality. The molecular mechanisms underpinning abnormal vascular wall remodeling are not fully understood. We hypothesized on the existence of a vascular tissue memory that may be transmitted through soluble signaling messengers, transferred from humans to healthy recipient animals, and consequently drive the recapitulation of arterial wall thickening and other vascular pathologies. We examined the effects of the intralesional infiltration for 6 days of arteriosclerotic popliteal artery-derived homogenates (100 µg of protein) into rats' full-thickness wounds granulation tissue. Animals infiltrated with normal saline solution or healthy brachial arterial tissue homogenate obtained from traumatic amputation served as controls. The significant thickening of arteriolar walls was the constant outcome in two independent experiments for animals receiving arteriosclerotic tissue homogenates. This material induced other vascular morphological changes including an endothelial cell phenotypic reprogramming that mirrored the donor's vascular histopathology. The immunohistochemical expression pattern of relevant vascular markers appeared to match between the human tissue and the corresponding recipient rats. These changes occurred within days of administration, and with no cross-species limitation. The identification of these "vascular disease drivers" may pave novel research avenues for atherosclerosis pathobiology.


Asunto(s)
Arteriosclerosis/metabolismo , Tejido de Granulación/metabolismo , Arteria Poplítea/lesiones , Proteínas/administración & dosificación , Lesiones del Sistema Vascular/inducido químicamente , Anciano , Animales , Arteriosclerosis/patología , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ratas , Lesiones del Sistema Vascular/patología
2.
J Nutr ; 151(10): 3036-3044, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34132332

RESUMEN

BACKGROUND: Bovine colostrum (BC) and chicken egg contain proteins possessing growth factor activity. Epidermal growth factor (EGF) provides much of the pro-reparative activity within BC. Clinical use of orally administered peptide growth factors is hampered by digestion from pancreatic proteases. OBJECTIVES: We examined whether adding a protease inhibitor [soybean trypsin inhibitor (SBTI) or ovomucoid] protected bioactivity of BC ± egg or EGF alone against pancreatic digestion using in vitro and in vivo models. METHODS: BC, egg, or EGF alone or in combination with trypsin inhibitors were tested for proliferative (Alamar blue) activity using human gastric adenocarcinoma (AGS) cells, prior to and after incubation with HCl/pepsin and trypsin/chymotrypsin. Data were analyzed using 2-factor ANOVA. Eight groups (n = 10) of adult female Sprague-Dawley rats (mean: 188.3 ± 0.8 g) received 20 mg/kg/d of BC + egg, 100 µg/d of EGF, 5 mg/d ovomucoid, or 10.8 mg/d SBTI, alone or in combination (in 1 mL 3% NaHCO3) by gavage for 9 d and dextran sodium sulfate (DSS; 5% in drinking water) for the final 7 d. Histology, microscopic damage score, and myeloperoxidase (MPO) were assessed and analyzed using 1-factor ANOVA. RESULTS: Proliferative activities of BC, egg, or EGF were reduced 40-57% by HCl/pepsin exposure and further reduced 14-24% by chymotrypsin/trypsin. Co-addition of SBTI or ovomucoid truncated the decrease in proliferative bioactivity caused by chymotrypsin/trypsin by 54-100% (P < 0.01). In vivo study showed oral EGF alone or protease inhibitors given alone were ineffective in reducing DSS damage, whereas SBTI with EGF or ovomucoid with BC + egg improved protective effects on weight gain, disease activity score, colonic MPO, and histology damage by 3-4-fold (P < 0.01). CONCLUSIONS: Studies using AGS, cells, and Sprague-Dawley rats showed the protease inhibitors ovomucoid and SBTI protected BC, egg, and EGF against loss of bioactivity due to pancreatic enzymes and, when given with NaHCO3, enhanced colonic protection against DSS damage.


Asunto(s)
Pollos , Inhibidores de Proteasas , Animales , Bovinos , Calostro , Digestión , Femenino , Péptidos y Proteínas de Señalización Intercelular , Embarazo , Ratas , Ratas Sprague-Dawley
3.
J Nutr ; 150(6): 1434-1442, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32286629

RESUMEN

BACKGROUND: Chicken eggs and bovine colostrum contain proteins possessing antimicrobial, immunoregulatory, and growth factor activity. The ability of eggs to influence gut defense and repair is largely unexplored. OBJECTIVE: We examined the effect of pasteurized spray-dried egg on gastrointestinal injury using cell culture and animal models and sought to determine whether adding colostrum provided extra benefit. METHODS: Egg alone, colostrum alone, and a 40:60 egg: colostrum combination were tested for proliferative (Alamar blue) and migratory (wounded monolayer) activity at 1 mg.mL-1 using human colon adenocarcinoma (Caco-2), human gastric cancer (AGS), and rat intestinal epithelioid-1 (RIE1) cells. Four groups of adult male C57BL/6 mice received 20 mg.kg-1.d-1 test products in drinking water for 7 d and indomethacin (85 mg.kg-1, administered subcutaneously) on day 7. Villus height and morphology were assessed. Three groups of adult male Sprague Dawley rats received 20 mg.kg-1.d-1 test product by gavage for 9 d and dextran sodium sulfate (DSS, 4% in drinking water) for the final 7 d. Histology, microscopic damage scoring, and myeloperoxidase were assessed. RESULTS: Egg or colostrum alone caused 3-fold increases in cell proliferation and migration (P < 0.05 compared with baseline). Heating the egg removed its bioactivity. Addition of neutralizing antibodies or tyrphostin showed that ovomucoid, ovalbumin, and the epidermal growth factor receptor mediated the effects of egg (all P < 0.05 compared with egg). Egg reduced shortening of villi caused by indomethacin in mice by 34% and reduced DSS-induced colonic damage in rats by 44-61% (P < 0.05 compared with DSS). Similar results were seen using colostrum alone. In each assay, the 40:60 combination gave improved results compared with the same dose of egg or colostrum alone (P < 0.05). CONCLUSIONS: Studies using AGS, RIE1, and Caco-2 cells, C57BL/6 mice, and Sprague Dawley rats showed protective effects of egg against gut injury. Enhanced results were seen if colostrum and egg were coadministered. Egg powder with or without colostrum may have therapeutic value for prevention and treatment of gut injuries.


Asunto(s)
Antiinflamatorios no Esteroideos/toxicidad , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Colitis/prevención & control , Suplementos Dietéticos , Huevos , Animales , Línea Celular , Pollos , Colitis/inducido químicamente , Modelos Animales de Enfermedad , Duodeno/efectos de los fármacos , Duodeno/lesiones , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Pasteurización , Polvos , Ratas
4.
Eur J Nutr ; 59(4): 1473-1479, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31123862

RESUMEN

PURPOSE: Bovine colostrum is available in health food shops and as a sports food supplement and is rich in antibodies and growth factors including IGF-1. World Anti-Doping Agency advises athletes against taking colostrum for fear of causing increased plasma IGF-1. There are also concerns that colostrum may theoretically stimulate malignancy in organs which express IGF-1 receptors. We, therefore, determined changes in plasma IGF-1 levels in subjects taking colostrum or placebo for 1 day, 4 weeks, and 12 weeks. METHODS: Plasma IGF1 levels were determined in healthy males (n = 16) who ingested 40 g bovine colostrum or placebo along with undertaking moderate exercise for total period of 4.5 h. Two further studies followed changes in IGF1 using double-blind, parallel group, placebo-controlled, randomized trials of colostrum or placebo (N = 10 per arm, 20 g/day for 4 weeks and N = 25 colostrum, N = 29 placebo arm 20 g/day for 12 weeks). RESULTS: Baseline IGF1 levels 130 ± 36 ng/ml. 4.5 h protocol showed no effect of colostrum on plasma IGF1 (ANOVA, treatment group: p = 0.400, group × time: p = 0.498, time p = 0.602). Similarly, no effect of colostrum ingestion was seen following 4 week (ANOVA, group: p = 0.584, group × time interaction: p = 0.083, time p = 0.243) or 12 week (ANOVA, group: p = 0.400, group × time interaction: p = 0.498, time p = 0.602) protocol. CONCLUSIONS: Ingestion of standard recommended doses of colostrum does not increase IGF-1 levels in healthy adults, providing additional support for the safety profile of colostrum ingestion.


Asunto(s)
Calostro/metabolismo , Suplementos Dietéticos , Factor I del Crecimiento Similar a la Insulina/efectos de los fármacos , Administración Oral , Adulto , Animales , Biomarcadores/sangre , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Leche , Valores de Referencia
5.
FASEB J ; 32(2): 1017-1024, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29046361

RESUMEN

Trefoil factor family (TFF) peptides are produced rapidly at sites of injury, stimulating epithelial migration, a process involving rapid changes in cell shape and volume, requiring rapid flow of water into and out of the cell. We examined the effect of TFFs on fluidity of cells by measuring their sensitivity to osmotic challenges and cell migration, and determined whether those results were mediated through altering the levels of aquaporins (AQPs), a family of transmembrane water channels involved in cellular water homeostasis. Gastric (AGS) and colonic (Caco-2) cell lines had intrinsic TFF levels determined and the predominant TFF peptide knocked down (RNA interference). Knockdown caused lessened responsiveness to changes in external osmotic challenge (by 51 and 69% in AGS and Caco-2 cells, respectively) and reduced cell migration and transepithelial permeability but did not influence proliferation. Exogenous TFF increased several AQPs, particularly AQP3, and those were reciprocally reduced in knockdown cells. TFF-induced, but not fetal calf serum-induced, cell migration was inhibited by the presence of AQP3 blocker (CuSO4). We summarize that TFF peptides promptly produced at sites of injury increase AQP levels, most notably AQP3, thereby enhancing the cells' ability to rapidly change their shape as part of the restitutive process. TFF peptides also require functioning AQP3 channels to induce cell migration.-Marchbank, T., Playford, R. J. Trefoil factor family peptides enhance cell migration by increasing cellular osmotic permeability and aquaporin 3 levels.


Asunto(s)
Acuaporina 3/metabolismo , Permeabilidad de la Membrana Celular , Movimiento Celular , Proliferación Celular , Ósmosis , Factores Trefoil/metabolismo , Acuaporina 3/antagonistas & inhibidores , Células CACO-2 , Sulfato de Cobre/farmacología , Humanos , Factores Trefoil/genética
6.
Eur J Appl Physiol ; 117(5): 931-941, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28290057

RESUMEN

PURPOSE: Intestinal cell damage due to physiological stressors (e.g. heat, oxidative, hypoperfusion/ischaemic) may contribute to increased intestinal permeability. The aim of this study was to assess changes in plasma intestinal fatty acid-binding protein (I-FABP) in response to exercise (with bovine colostrum supplementation, Col, positive control) and compare this to intestinal barrier integrity/permeability (5 h urinary lactulose/rhamnose ratio, L/R). METHODS: In a double-blind, placebo-controlled, crossover design, 18 males completed two experimental arms (14 days of 20 g/day supplementation with Col or placebo, Plac). For each arm participants performed two baseline (resting) intestinal permeability assessments (L/R) pre-supplementation and one post-exercise following supplementation. Blood samples were collected pre- and post-exercise to determine I-FABP concentration. RESULTS: Two-way repeated measures ANOVA revealed an arm × time interaction for L/R and I-FABP (P < 0.001). Post hoc analyses showed urinary L/R increased post-exercise in Plac (273% of pre, P < 0.001) and Col (148% of pre, P < 0.001) with post-exercise values significantly lower with Col (P < 0.001). Plasma I-FABP increased post-exercise in Plac (191% of pre-exercise, P = 0.002) but not in the Col arm (107%, P = 0.862) with post-exercise values significantly lower with Col (P = 0.013). Correlations between the increase in I-FABP and L/R were evident for visit one (P = 0.044) but not visit two (P = 0.200) although overall plots/patterns do appear similar for each. CONCLUSION: These findings suggest that exercise-induced intestinal cellular damage/injury is partly implicated in changes in permeability but other factors must also contribute.


Asunto(s)
Ejercicio Físico , Proteínas de Unión a Ácidos Grasos/sangre , Absorción Intestinal , Mucosa Intestinal/metabolismo , Adulto , Animales , Bovinos , Calostro , Humanos , Lactulosa/orina , Masculino , Ramnosa/orina
7.
Nat Genet ; 39(7): 827-9, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17558408

RESUMEN

We tested 310,605 SNPs for association in 778 individuals with celiac disease and 1,422 controls. Outside the HLA region, the most significant finding (rs13119723; P = 2.0 x 10(-7)) was in the KIAA1109-TENR-IL2-IL21 linkage disequilibrium block. We independently confirmed association in two further collections (strongest association at rs6822844, 24 kb 5' of IL21; meta-analysis P = 1.3 x 10(-14), odds ratio = 0.63), suggesting that genetic variation in this region predisposes to celiac disease.


Asunto(s)
Enfermedad Celíaca/genética , Predisposición Genética a la Enfermedad , Variación Genética , Genoma Humano , Interleucina-2/genética , Interleucinas/genética , Animales , Cromosomas Humanos Par 4/genética , Humanos , Desequilibrio de Ligamiento , Ratones , Polimorfismo de Nucleótido Simple , Factores de Riesgo
8.
Nat Commun ; 15(1): 2910, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38632262

RESUMEN

Malnutrition underlies almost half of all child deaths globally. Severe Acute Malnutrition (SAM) carries unacceptable mortality, particularly if accompanied by infection or medical complications, including enteropathy. We evaluated four interventions for malnutrition enteropathy in a multi-centre phase II multi-arm trial in Zambia and Zimbabwe and completed in 2021. The purpose of this trial was to identify therapies which could be taken forward into phase III trials. Children of either sex were eligible for inclusion if aged 6-59 months and hospitalised with SAM (using WHO definitions: WLZ <-3, and/or MUAC <11.5 cm, and/or bilateral pedal oedema), with written, informed consent from the primary caregiver. We randomised 125 children hospitalised with complicated SAM to 14 days treatment with (i) bovine colostrum (n = 25), (ii) N-acetyl glucosamine (n = 24), (iii) subcutaneous teduglutide (n = 26), (iv) budesonide (n = 25) or (v) standard care only (n = 25). The primary endpoint was a composite of faecal biomarkers (myeloperoxidase, neopterin, α1-antitrypsin). Laboratory assessments, but not treatments, were blinded. Per-protocol analysis used ANCOVA, adjusted for baseline biomarker value, sex, oedema, HIV status, diarrhoea, weight-for-length Z-score, and study site, with pre-specified significance of P < 0.10. Of 143 children screened, 125 were randomised. Teduglutide reduced the primary endpoint of biomarkers of mucosal damage (effect size -0.89 (90% CI: -1.69,-0.10) P = 0.07), while colostrum (-0.58 (-1.4, 0.23) P = 0.24), N-acetyl glucosamine (-0.20 (-1.01, 0.60) P = 0.67), and budesonide (-0.50 (-1.33, 0.33) P = 0.32) had no significant effect. All interventions proved safe. This work suggests that treatment of enteropathy may be beneficial in children with complicated malnutrition. The trial was registered at ClinicalTrials.gov with the identifier NCT03716115.


Asunto(s)
Enfermedades Intestinales , Desnutrición , Desnutrición Aguda Severa , Animales , Bovinos , Humanos , Lactante , Acetilglucosamina , Biomarcadores , Budesonida , Edema , Zambia , Zimbabwe , Preescolar
9.
Am J Physiol Renal Physiol ; 305(3): F382-9, 2013 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-23698120

RESUMEN

Pancreatic secretory trypsin inhibitor (PSTI) is expressed in most bladder carcinomas, where its pathophysiological relevance is unclear. Using recombinant normal sequence PSTI/tumor-associated trypsin inhibitor (TATI), a variant associated with familial pancreatitis (N34S), an active site-inactivated variant (R18/V19), and immunoneutralization and RNA interference-mediated knockdown techniques, we investigated the actions of PSTI/TATI on cell migration (wounding monolayers), collagen invasion (gel invasion assays), and proliferation (Alamar blue) on 253J, RT4, and HT1376 human bladder carcinoma cell lines. All three forms of PSTI/TATI stimulated migration twofold, and normal sequence PSTI/TATI showed synergistic promigratory effects when added with EGF. Addition of structurally unrelated soybean trypsin inhibitor had no promigratory activity. Similar results were seen using collagen invasion assays, although the active site mutated variant had no proinvasive activity, probably due to reduced Akt2 activation. PSTI/TATI did not stimulate proliferation despite acting, at least partially, through the EGF receptor, as effects of PSTI/TATI were truncated by the addition of an EGF receptor blocking antibody or the tyrosine kinase inhibitor tyrphostin. Cell lines produced endogenous PSTI/TATI, and PSTI/TATI RNA interference knockdown or the addition of PSTI/TATI, EGF receptor, or tyrphostin blocking agents reduced migration and invasion below baseline. PSTI/TATI induced phosphorylation of the EGF receptor, ERK1 and ERK2, Akt2 and Akt3, JNK1, MKK3, and ribosomal protein S6 kinase 1. This profile was more limited than that induced by EGF and did not include Akt1, probably explaining the lack of proproliferative activity. Our findings of autocrine stimulation and synergistic responses between EGF and PSTI/TATI at concentrations found in urine and tissue suggest that PSTI/TATI has pathophysiological relevance.


Asunto(s)
Comunicación Autocrina/efectos de los fármacos , Proteínas Portadoras/farmacología , Movimiento Celular/efectos de los fármacos , Receptores ErbB/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias de la Vejiga Urinaria/patología , Western Blotting , Línea Celular Tumoral , Proliferación Celular , Colágeno/metabolismo , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Fosforilación , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Proteínas Recombinantes/biosíntesis , Inhibidor de Tripsina Pancreática de Kazal
10.
Am J Physiol Gastrointest Liver Physiol ; 303(11): G1270-8, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22982339

RESUMEN

Subepithelial myofibroblasts are involved in the initiation and coordination of intestinal epithelial repair, but the molecular signaling pathways are largely unknown. The cellular adaptations that occur during repair range from dedifferentiation and migration to proliferation and redifferentiation, in a way that is strongly reminiscent of normal crypt-to-villus epithelial maturation. We therefore hypothesized that Wnt/ß-catenin signaling may have a pivotal role in intestinal epithelial wound repair. We used the established scratch wound method in Caco-2 cells and in nontransformed NCM460 cells to monitor the effects of IL-1ß-stimulated colonic myofibroblasts (CCD-18co) on intestinal epithelial repair, with immunoblotting and immunodepletion to examine the conditioned media. Conditioned media from IL-1ß-stimulated, but not -untreated, myofibroblasts increased Caco-2 wound closure twofold over 24 h. IL-1ß-stimulated myofibroblasts downregulated the differentiation marker sucrase-isomaltase in the Caco-2 cells, whereas the proliferation marker c-myc was upregulated. Array expression profiling identified Wnt-5a as the Wnt-related gene that was most upregulated (28-fold) by IL-1ß stimulation of CCDs. Recombinant Wnt-5a enhanced proliferation of Caco-2 and NCM460 cells. In scratch assays, it increased migration of the leading edge in both cell lines. Wnt-5a immunodepletion of the IL-1ß-CCD conditioned media abrogated the ability to enhance the repair. Wnt-5a often acts through a noncanonical signal transduction pathway. Further experiments supported this pathway in epithelial wound healing: IL-1ß-CCD-mediated repair was not affected by the addition of the canonical Wnt antagonist Dickkopf-1. Furthermore, media from stimulated myofibroblasts (but not Wnt-5a-depleted media) increased c-jun in Caco-2 cell nuclear extracts. Myofibroblast-mediated noncanonical Wnt-5a signaling is therefore important in the dedifferentiation and migration stages of epithelial wound repair.


Asunto(s)
Interleucina-1beta/farmacología , Miofibroblastos/efectos de los fármacos , Proteínas Proto-Oncogénicas/fisiología , Proteínas Wnt/fisiología , Cicatrización de Heridas/efectos de los fármacos , Células CACO-2 , Desdiferenciación Celular , Línea Celular , Movimiento Celular , Medios de Cultivo Condicionados/farmacología , Regulación hacia Abajo , Humanos , Miofibroblastos/fisiología , Proteínas Proto-Oncogénicas/biosíntesis , Transducción de Señal/efectos de los fármacos , Regulación hacia Arriba , Proteínas Wnt/biosíntesis , Proteína Wnt-5a , Cicatrización de Heridas/fisiología , beta Catenina/metabolismo
11.
Nutrients ; 14(21)2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36364868

RESUMEN

Bovine colostrum (BC) has anti-inflammatory, anti-infective, growth and intestinal repair factors that may be beneficial in Crohn's disease (CD). We assessed whether daily BC for up to 3 months was acceptable to children and young people (CYP) with CD in remission or of mild/moderate severity. CYP were randomised to receive either BC or matching placebo milk daily for 6 weeks (blinded phase); all received BC for the following 6 weeks (open phase). In 23 CYP, median (inter-quartile range) age was 15.2 (13.9-16.1) years and 9 (39.1%) were girls. A similar proportion of CYP in the BC and placebo arms completed the blinded phase (8/12, 75.0% and 9/11, 81.8% respectively). Twelve (70.6%) CYP completed the open phase with 7 (58.3%) tolerating BC for 3 months. Diaries in weeks 2, 6 and 12 revealed that most CYP took BC every day (5/7, 71.4%; 5/8, 62.5% and 6/11, 54.5% respectively). In interviews, opinions were divided as to preference of BC over the placebo milk and some preferred BC over other nutritional supplements. Symptoms, clinical and laboratory variables and quality of life were similar in the two arms. BC may be an acceptable nutritional supplement for daily, longer-term use in CYP with CD.


Asunto(s)
Enfermedad de Crohn , Niño , Femenino , Humanos , Animales , Bovinos , Adolescente , Masculino , Enfermedad de Crohn/tratamiento farmacológico , Estudios de Factibilidad , Calidad de Vida , Inducción de Remisión
12.
Lab Invest ; 91(12): 1684-94, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21876537

RESUMEN

Dimethyloxalylglycine (DMOG) is an inhibitor of prolyl-4-hydroxylase domain enzymes. Its potential value and mechanism of actions in preventing/treating gastrointestinal injury are, however, poorly understood. We, therefore, examined the effect of DMOG on influencing gut injury and repair using a variety of in vitro and in vivo models. We performed in vitro studies utilising pro-migratory (wounded monolayer) and proliferation (using DNA quantitation) assays of human stomach (AGS) and colonic (HT29) carcinoma cells. Time course studies examined changes in hypoxia-inducible factor (HIF) and vascular endothelial growth factor (VEGF) levels, a growth factor known to be regulated via HIF. In vivo studies utilised a rat gastric (indomethacin, 20 mg/kg and 3 h restraint) damage model. DMOG stimulated migration in a dose-dependent manner, increasing migration twofold when added at 25µM (P<0.01). Additive effects were seen when DMOG was added to cells in hypoxic conditions. DMOG stimulated proliferation dose dependently, increasing proliferation threefold when added at 70 µM (P<0.01). DMOG caused upregulation of both HIF and VEGF within 4 h of administration. Addition of VEGF neutralising antibody truncated migratory and proliferative activity of DMOG by about 70%. Both oral and subcutaneous administration of DMOG decreased gastric injury without influencing intragastric pH (50% reduction in injury when 1 ml gavaged at 0.57 mM, P < 0.01). Indomethacin reduced tissue HIF and VEGF levels but this was prevented if DMOG was present. In conclusion, DMOG stimulates the early phases of gut repair and VEGF-dependent processes appear relevant. Non-peptide factors such as this may be useful to stabilise or repair gut mucosa.


Asunto(s)
Aminoácidos Dicarboxílicos/uso terapéutico , Enfermedades Gastrointestinales/tratamiento farmacológico , Factor 1 Inducible por Hipoxia/metabolismo , Regeneración/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Aminoácidos Dicarboxílicos/farmacología , Animales , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Células HT29 , Humanos , Masculino , Ratas , Ratas Sprague-Dawley
13.
Am J Physiol Gastrointest Liver Physiol ; 300(3): G477-84, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21148400

RESUMEN

Heavy exercise causes gut symptoms and, in extreme cases, "heat stroke" partially due to increased intestinal permeability of luminal toxins. We examined bovine colostrum, a natural source of growth factors, as a potential moderator of such effects. Twelve volunteers completed a double-blind, placebo-controlled, crossover protocol (14 days colostrum/placebo) prior to standardized exercise. Gut permeability utilized 5 h urinary lactulose-to-rhamnose ratios. In vitro studies (T84, HT29, NCM460 human colon cell lines) examined colostrum effects on temperature-induced apoptosis (active caspase-3 and 9, Baxα, Bcl-2), heat shock protein 70 (HSP70) expression and epithelial electrical resistance. In both study arms, exercise increased blood lactate, heart rate, core temperature (mean 1.4°C rise) by similar amounts. Gut hormone profiles were similar in both arms although GLP-1 levels rose following exercise in the placebo but not the colostrum arm (P = 0.026). Intestinal permeability in the placebo arm increased 2.5-fold following exercise (0.38 ± 0.012 baseline, to 0.92 ± 0.014, P < 0.01), whereas colostrum truncated rise by 80% (0.38 ± 0.012 baseline to 0.49 ± 0.017) following exercise. In vitro apoptosis increased by 47-65% in response to increasing temperature by 2°C. This effect was truncated by 60% if colostrum was present (all P < 0.01). Similar results were obtained examining epithelial resistance (colostrum truncated temperature-induced fall in resistance by 64%, P < 0.01). Colostrum increased HSP70 expression at both 37 and 39°C (P < 0.001) and was truncated by addition of an EGF receptor-neutralizing antibody. Temperature-induced increase in Baxα and reduction in Bcl-2 was partially reversed by presence of colostrum. Colostrum may have value in enhancing athletic performance and preventing heat stroke.


Asunto(s)
Atletas , Calostro/metabolismo , Suplementos Dietéticos , Golpe de Calor/prevención & control , Absorción Intestinal , Mucosa Intestinal/metabolismo , Esfuerzo Físico , Adulto , Animales , Apoptosis , Proteínas Reguladoras de la Apoptosis/metabolismo , Biomarcadores/sangre , Biomarcadores/orina , Bovinos , Estudios Cruzados , Método Doble Ciego , Impedancia Eléctrica , Femenino , Hormonas Gastrointestinales/sangre , Proteínas HSP70 de Choque Térmico/metabolismo , Células HT29 , Golpe de Calor/etiología , Golpe de Calor/metabolismo , Calor , Humanos , Intestinos/patología , Ácido Láctico/sangre , Lactosa/orina , Masculino , Permeabilidad , Efecto Placebo , Embarazo , Ramnosa/orina , Adulto Joven
14.
Br J Nutr ; 105(9): 1303-10, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21272405

RESUMEN

Cordyceps sinensis (CS) is a traditional Chinese medicine and health food used to support many organ systems. It is commercially produced by cultivation in a liquid medium or on a solid (grain/potato) phase. We tested the effects of hot water extracts of liquid-phase and solid-phase commercially grown CS on its ability to influence proliferation (using Alamar blue, an oxidation/reduction indicator), migration (serial-wounded monolayer photomicroscopy), invasion through collagen gel (fluorometric assay) and indomethacin-induced apoptosis (active caspase-3 colorimetric assay) of human colon cancer HT29 cells. An in vivo study used a rat gastric damage model (indomethacin 20 mg/kg and 4 h restraint with oral administration). The CS extract stimulated cell proliferation threefold when added at 10 µg/ml (P < 0·01). Cell migration increased by 69 % and invasion by 17 % when CS was added at 5 mg/ml (P < 0·01). The results also showed that 93 % of the pro-proliferative activity was soluble in ethanol, whereas pro-migratory activity was divided (61:49) into both ethanol-soluble and ethanol-insoluble sub-fractions. Indomethacin-induced apoptosis was not affected by the presence of CS. CS reduced the amount of gastric injury by 63 % when administered orally at 20 mg/ml (P < 0·01), the results being similar to using the potent cytoprotective agent epidermal growth factor at 25 µg/ml (83 % reduction). We conclude that both methods of cultivated CS possess biological activity when analysed using a variety of gut models of injury and repair. Functional foods, such as CS, could provide a novel approach for the prevention and treatment of injury to the bowel.


Asunto(s)
Cordyceps/química , Medicamentos Herbarios Chinos/farmacología , Extractos Vegetales/farmacología , Gastropatías/tratamiento farmacológico , Animales , Antiinflamatorios no Esteroideos/efectos adversos , Movimiento Celular/efectos de los fármacos , Proliferación Celular , Suplementos Dietéticos , Medicamentos Herbarios Chinos/química , Células HT29 , Humanos , Indometacina/efectos adversos , Medicina Tradicional China , Extractos Vegetales/química , Ratas , Ratas Sprague-Dawley , Restricción Física , Gastropatías/inducido químicamente
15.
Nutrients ; 13(3)2021 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-33809940

RESUMEN

Small intestinal bacterial overgrowth (SIBO) occurs commonly, is difficult to treat, and frequently recurs. Bovine colostrum (BC) and chicken eggs contain immunoglobulins and other components that possess antimicrobial, immunoregulatory, and growth factor activities; however, it is not known if they have the ability to reduce injury caused by the presence of bacteria associated with SIBO (Streptococcus, Escherichia coli, Staphylococcus, Bacteroides, Klebsiella, Enterococcus, and Proteus) and infectious diarrhea (enteropathogenic Escherichia coli, Salmonella). We examined the effects of BC, egg, or the combination, on bacterial growth and bacteria-induced changes in transepithelial electrical resistance (TEER) and bacterial translocation across confluent Caco-2 monolayers. BC, egg, or the combination did not affect bacterial growth. Adding bacteria to monolayers reduced TEER and (with minor variations among species) increased bacterial translocation, increased monolayer apoptosis (increased caspase-3 and Baxα, reduced Bcl2), increased intercellular adhesion molecule 1 (ICAM-1), and reduced cell adhesion molecules zonulin1 (ZO1) and claudin-1. BC, egg, or the combination reduced these effects (all p < 0.01) and caused additional increases in vascular endothelial growth factor (VEGF) and Heat Shock Protein 70 (Hsp70) expression. We conclude that BC ± egg strengthens mucosal integrity against a battery of bacteria relevant for SIBO and for infectious diarrhea. Oral BC ± egg may have clinical value for these conditions, especially SIBO where eradication of precipitating organisms may be difficult to achieve.


Asunto(s)
Infecciones Bacterianas/complicaciones , Calostro/metabolismo , Disentería/tratamiento farmacológico , Disentería/etiología , Intestino Delgado/microbiología , Óvulo/metabolismo , Animales , Infecciones Bacterianas/tratamiento farmacológico , Células CACO-2 , Bovinos , Humanos , Técnicas In Vitro , Enfermedades Intestinales/tratamiento farmacológico , Enfermedades Intestinales/etiología , Enfermedades Intestinales/microbiología
16.
Artículo en Inglés | MEDLINE | ID: mdl-36994347

RESUMEN

Lower limb ulcers in type-2 diabetic patients are a frequent complication that tributes to amputation and reduces survival. We hypothesized that diabetic healing impairment and other histopathologic hallmarks are mediated by a T2DM-induced tissue priming/metabolic memory that can be transferred from humans to healthy recipient animals and consequently reproduce diabetic donor's phenotypes. We examined the effect of human T2DM tissue homogenates injected into non-diabetic rat excisional wounds. Fresh granulation tissue, popliteal artery, and peroneal nerve of patients with T2DM were obtained following amputation. Post-mammoplasty granulation and post-traumatic amputation-tissue of normal subjects acted as controls. The homogenates were intralesionally injected for 6-7 days into rats' excisional thickness wounds. Infiltration with the different homogenates caused impaired wound closure, inflammation, nerve degeneration, and arterial thickening (all P < 0.01 vs relevant control) resembling histopathology of diabetic donor tissues. Control materials caused marginal inflammation only. Infiltration with glycated bovine albumin provoked inflammation and wound healing delay but did not induce arterial thickening. The reproduction of human diabetic traits in healthy recipient animals through a tissue homogenate support the notion on the existence of tissue metabolic memory-associated and transmissible factors, involved in the pathogenesis of diabetic complications. These may have futuristic clinical implications for medical interventions.

17.
PLoS One ; 15(1): e0227059, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31923181

RESUMEN

Intestinal ischemia/reperfusion (I/R) injury occurs during transplantation, mesenteric arterial occlusion, trauma and shock, causing systemic inflammation, multiple organ dysfunction and high mortality. Pancreatic secretory trypsin inhibitor (PSTI), a serine protease inhibitor expressed in gut mucosa may function as a mucosal protective/repair peptide. We examined whether PSTI affected mesenteric I/R-induced injury. Hypoxia/normoxia (H/N) caused 50% drop in cell viability of AGS, RIE1 and Caco-2 cells but PSTI (10 µg/ml) given prior- or during-hypoxic period improved survival by 50% (p<0.01). Similarly, Caco-2 monolayers exposed to H/N had 300% increase in transepithelial permeability, PSTI truncated this by 50% (p<0.01). Mice underwent mesenteric I/R by clamping jejunum, causing severe mucosal injury, increased apoptotic markers and 3-fold increases in plasma IL-6, IL1ß, TNFα, and tissue lipid peroxidation (MDA) and inflammatory infiltration (MPO) levels. Lungs showed similar significant injury and inflammatory infiltrate markers. Smaller increases in MDA and MPO were seen in kidney & liver. PSTI (20 mg/kg) reduced all injury markers by 50-80% (p<0.01). In vitro and in vivo studies showed PSTI reduced pro-apoptotic Caspase 3, 9 and Baxα levels, normalised Bcl2 and caused additional increases in HIF1α, VEGF and Hsp70 above rises caused by I/R alone (all p<0.01). PSTI also prevented reduction of tight junction molecules ZO1 and Claudin1 (all p<0.01) but did not affect increased ICAM-1 caused by I/R in gut or lung. PSTI may be a useful clinical target to prevent I/R injury.


Asunto(s)
Mucosa Intestinal/lesiones , Mesenterio/lesiones , Daño por Reperfusión/tratamiento farmacológico , Inhibidor de Tripsina Pancreática de Kazal/farmacología , Animales , Apoptosis , Células CACO-2 , Humanos , Inflamación , Mucosa Intestinal/metabolismo , Lesión Pulmonar/prevención & control , Ratones , Daño por Reperfusión/patología , Daño por Reperfusión/prevención & control , Migración Transendotelial y Transepitelial , Inhibidor de Tripsina Pancreática de Kazal/uso terapéutico
18.
PLoS One ; 15(10): e0240392, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33022011

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0234719.].

19.
PLoS One ; 15(6): e0234719, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32555629

RESUMEN

BACKGROUND: Colostrum, the milk produced during first few days after birth, is rich in immunoglobulins, antimicrobial peptides & growth factors. Multiple clinical trials using bovine colostrum are ongoing but with no assessment of test product bioactivity. OBJECTIVES: To examine variability of bioactivity between 20 commercial colostrum products, contribution of TGFß and EGFR in mediating effects, heat sensitivity of bioactivity and changes in bioactivity of colostrum milkings in the days following calving. DESIGN: In vitro bioactivity used AGS, RIE-1 and Caco-2 cell proliferation (Alamar blue) and migration (wounded monolayers) assays. Changes in colostrum bioactivity determined following addition of TGFß-neutralising antibody, EGFR blocker (Typhostin) and after heating (40-60°C, 60 min). In vivo bioassay assessed ability of colostrum gavage (2ml, 7mg/ml) to reduce gastric damage (NSAID + restraint) in rats. Milkings from 6 cows, days 0-3 post calving were assessed for bioactivity and growth factor concentrations. RESULT: Six-fold differences in pro-proliferative and migratory activity were seen comparing commercial products. Comparison of most- and least-active samples from in vitro studies showed two- to three-fold differences in ability to reduce gastric injury (86% reduction using most-active vs 48% using least-active, p<0.01). Tyrphostin reduced pro-migratory and proliferative activity by 23% and 55%. TGFß neutralisation reduced migratory activity by 83% but did not affect proliferation Heating colostrum powder to 50°C did not affect immunoactivity of haptoglobin, EGF, TGFß, IgG, IGF-1 or betacellulin but decreased bioactivity by >40%. Milking studies showed high bioactivity during first and second milkings on day 0 but 77% reduction by day 3. Changes in total protein, haptoglobin, EGF, TGFß, IgG and IGF-1 paralleled falls in bioactivity. CONCLUSION: Commercial colostrum products possess widely different bioactivity. Variation in heat exposure and/or proportion of day 0 colostrum content may contribute to this. Assessment of colostrum bioactivity has advantages to growth factor quantitation for quality control.


Asunto(s)
Ensayos Clínicos como Asunto , Calostro/metabolismo , Anciano , Animales , Células CACO-2 , Bovinos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Receptores ErbB/metabolismo , Femenino , Calor , Humanos , Masculino , Embarazo , Factor de Crecimiento Transformador beta/metabolismo
20.
Peptides ; 126: 170269, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32045621

RESUMEN

The insulin signaling pathway plays a pivotal role in glucose metabolism and metabolic homeostasis. Disruption of this pathway is commonly seen in critical illness such as following severe burn injuries where homeostatic control is lost, leading to "insulin resistance" with poor blood glucose control. The aberrant signaling pathways involved in insulin resistance following burn injury include increases in hyperglycemic stress hormones, pro-inflammatory cytokines and free radical production. Leakage of mitochondrial sequestered self-antigens and signaling between mitochondria and endoplasmic reticulum also contribute to insulin resistance. Greater understanding of molecular processes involved in burn-related insulin resistance could potentially lead to the development of novel therapeutic approaches to improve patient management.


Asunto(s)
Quemaduras/metabolismo , Hiperglucemia/metabolismo , Hiperglucemia/patología , Resistencia a la Insulina , Mitocondrias/patología , Animales , Humanos
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