Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
PNAS Nexus ; 2(1): pgac309, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36744021

RESUMEN

Rapid changes in the global climate are deepening existing health disparities from resource scarcity and malnutrition. Rising ambient temperatures represent an imminent risk to pregnant women and infants. Both maternal malnutrition and heat stress during pregnancy contribute to poor fetal growth, the leading cause of diminished child development in low-resource settings. However, studies explicitly examining interactions between these two important environmental factors are lacking. We leveraged maternal and neonatal anthropometry data from a randomized controlled trial focused on improving preconception maternal nutrition (Women First Preconception Nutrition trial) conducted in Thatta, Pakistan, where both nutritional deficits and heat stress are prevalent. Multiple linear regression of ambient temperature and neonatal anthropometry at birth (n = 459) showed a negative association between daily maximal temperatures in the first trimester and Z-scores of birth length and head circumference. Placental mRNA-sequencing and protein analysis showed transcriptomic changes in protein translation, ribosomal proteins, and mTORC1 signaling components in term placenta exposed to excessive heat in the first trimester. Targeted metabolomic analysis indicated ambient temperature associated alterations in maternal circulation with decreases in choline concentrations. Notably, negative impacts of heat on birth length were in part mitigated in women randomized to comprehensive maternal nutritional supplementation before pregnancy suggesting potential interactions between heat stress and nutritional status of the mother. Collectively, the findings bridge critical gaps in our current understanding of how maternal nutrition may provide resilience against adverse effects of heat stress in pregnancy.

2.
Front Microbiol ; 13: 823757, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35979501

RESUMEN

Objective: To characterize the changes in gut microbiota during pregnancy and determine the effects of nutritional intervention on gut microbiota in women from sub-Saharan Africa (the Democratic Republic of the Congo, DRC), South Asia (India and Pakistan), and Central America (Guatemala). Methods: Pregnant women in the Women First (WF) Preconception Maternal Nutrition Trial were included in this analysis. Participants were randomized to receive a lipid-based micronutrient supplement either ≥3 months before pregnancy (Arm 1); started the same intervention late in the first trimester (Arm 2); or received no nutrition supplements besides those self-administered or prescribed through local health services (Arm 3). Stool and blood samples were collected during the first and third trimesters. Findings presented here include fecal 16S rRNA gene-based profiling and systemic and intestinal inflammatory biomarkers, including alpha (1)-acid glycoprotein (AGP), C-reactive protein (CRP), fecal myeloperoxidase (MPO), and calprotectin. Results: Stool samples were collected from 640 women (DRC, n = 157; India, n = 102; Guatemala, n = 276; and Pakistan, n = 105). Gut microbial community structure did not differ by intervention arm but changed significantly during pregnancy. Richness, a measure of alpha-diversity, decreased over pregnancy. Community composition (beta-diversity) also showed a significant change from first to third trimester in all four sites. Of the top 10 most abundant genera, unclassified Lachnospiraceae significantly decreased in Guatemala and unclassified Ruminococcaceae significantly decreased in Guatemala and DRC. The change in the overall community structure at the genus level was associated with a decrease in the abundances of certain genera with low heterogeneity among the four sites. Intervention arms were not significantly associated with inflammatory biomarkers at 12 or 34 weeks. AGP significantly decreased from 12 to 34 weeks of pregnancy, whereas CRP, MPO, and calprotectin did not significantly change over time. None of these biomarkers were significantly associated with the gut microbiota diversity. Conclusion: The longitudinal reduction of individual genera (both commensals and potential pathogens) and alpha-diversity among all sites were consistent and suggested that the effect of pregnancy on the maternal microbiota overrides other influencing factors, such as nutrition intervention, geographical location, diet, race, and other demographical variables.

3.
Commun Biol ; 4(1): 53, 2021 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-33420329

RESUMEN

The G protein-coupled receptor 109 A (GPR109A) is robustly expressed in osteoclastic precursor macrophages. Previous studies suggested that GPR109A mediates effects of diet-derived phenolic acids such as hippuric acid (HA) and 3-(3-hydroxyphenyl) propionic acid (3-3-PPA) on promoting bone formation. However, the role of GPR109A in metabolic bone homeostasis and osteoclast differentiation has not been investigated. Using densitometric, bone histologic and molecular signaling analytic methods, we uncovered that bone mass and strength were significantly higher in tibia and spine of standard rodent diet weaned 4-week-old and 6-month-old GPR109A gene deletion (GPR109A-/-) mice, compared to their wild type controls. Osteoclast numbers in bone and in ex vivo bone marrow cell cultures were significantly decreased in GPR109A-/- mice compared to wild type controls. In accordance with these data, CTX-1 in bone marrow plasma and gene expression of bone resorption markers (TNFα, TRAP, Cathepsin K) were significantly decreased in GPR109A-/- mice, while on the other hand, P1NP was increased in serum from both male and female GPR109A-/- mice compared to their respective controls. GPR109A deletion led to suppressed Wnt/ß-catenin signaling in osteoclast precursors to inhibit osteoclast differentiation and activity. Indeed, HA and 3-3-PPA substantially inhibited RANKL-induced GPR109A expression and Wnt/ß-catenin signaling in osteoclast precursors and osteoclast differentiation. Resultantly, HA significantly inhibited bone resorption and increased bone mass in wild type mice, but had no additional effects on bone in GPR109A-/- mice compared with their respective untreated control mice. These results suggest an important role for GPR109A during osteoclast differentiation and bone resorption mediating effects of HA and 3-3-PPA on inhibiting bone resorption during skeletal development.


Asunto(s)
Resorción Ósea/prevención & control , Hipuratos/farmacología , Osteogénesis/efectos de los fármacos , Fenilpropionatos/farmacología , Receptores Acoplados a Proteínas G/metabolismo , Animales , Evaluación Preclínica de Medicamentos , Femenino , Microbioma Gastrointestinal , Hipuratos/uso terapéutico , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Fenilpropionatos/uso terapéutico , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Receptores Acoplados a Proteínas G/genética , Vía de Señalización Wnt
4.
BMJ Open ; 10(3): e034338, 2020 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-32152169

RESUMEN

INTRODUCTION: Obesity is a major health concern in postmenopausal women, and chronic low-grade inflammation contributes to the development of obesity. Cellular studies and high-fat-diet-induced obese mouse model mimicking obesity show the antiobesity effect of annatto-extracted tocotrienols (TT) with antioxidant capability. We aim to assess the safety and efficacy of TT consumption for lipid-related parameters in obese postmenopausal women. METHODS AND ANALYSIS: Eligible obese postmenopausal women will be randomly assigned to placebo group (430 mg olive oil) and TT group (DeltaGold Tocotrienol 70%) for 24 weeks. In the present study, the primary outcome is total/regional fat mass and visceral adipose tissue. The secondary outcomes include lipid profile in serum, mRNA expression of fatty acid synthase and carnitine palmitoyltransferase 1A in fat tissue, oxylipins and endocannabinoids in plasma and adipose tissue, abundance and composition of intestinal microbiome in faeces, high-sensitivity C-reactive protein (hs-CRP) in serum and leptin in serum. Every participant will be evaluated at 0 (prior to starting intervention) and 24 weeks of intervention, except for serum lipid profile and hs-CRP at 0, 12 and 24 weeks. 'Intent-to-treat' principle is employed for data analysis. Hierarchical linear modelling is used to estimate the effects of dietary TT supplementation while properly accounting for dependency of data and identified covariates. To our knowledge, this is the first randomised, placebo-controlled, double-blinded study to determine dietary TT supplementation on an obese population. If successful, this study will guide the future efficacy TT interventions and TT can be implemented as an alternative for obese population in antiobesity management. ETHICS AND DISSEMINATION: This study has been approved by the Bioethics Committee of the Texas Tech University Health Sciences Center, Lubbock. An informed consent form will be signed by a participant before enrolling in the study. The results from this trial will be actively disseminated through academic conference presentation and peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT03705845.


Asunto(s)
Obesidad/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Posmenopausia , Adulto , Biomarcadores , Bixaceae , Pesos y Medidas Corporales , Proteína C-Reactiva/análisis , Carnitina O-Palmitoiltransferasa/análisis , Carotenoides , Método Doble Ciego , Endocannabinoides/análisis , Ácido Graso Sintasas/sangre , Femenino , Humanos , Leptina/sangre , Lípidos/sangre , Persona de Mediana Edad , Oxilipinas/análisis , Extractos Vegetales/administración & dosificación , Tocotrienoles
5.
J Nutr Biochem ; 66: 63-69, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30771735

RESUMEN

Gut microbiota contributes to the biological activities of berry anthocyanins by transforming them into bioactive metabolites, and anthocyanins support the growth of specific bacteria, indicating a two-way relationship between anthocyanins and microbiota. In the present study, we tested the hypothesis that strawberry supplementation alters gut microbial ecology in diabetic db/db mice. Control (db/+) and diabetic (db/db) mice (7 weeks old) consumed standard diet or diet supplemented with 2.35% freeze-dried strawberry (db/db + SB) for 10 weeks. Colon contents were used to isolate bacterial DNA. V4 variable region of 16S rRNA gene was amplified. Data analyses were performed using standardized pipelines (QIIME 1.9 and R packages). Differences in predictive metagenomics function were identified by PICRUSt. Principal coordinate analyses confirmed that the microbial composition was significantly influenced by both host genotype and strawberry consumption. Further, α-diversity indices and ß-diversity were different at the phylum and genus levels, and genus and operational taxonomical units levels, respectively (P<.05). At the phylum level, strawberry supplementation decreased the abundance of Verrucomicrobia in db/db + SB vs. db/db mice (P<.05). At the genus level, db/db mice exhibited a decrease in the abundance of Bifidobacterium, and strawberry supplementation increased Bifidobacterium in db/db + SB vs. db/db mice (P<.05). PICRUSt revealed significant differences in 45 predicted metabolic functions among the 3 groups. Our study provides evidence for marked changes in the composition and functional potential of the gut microbiome with strawberry supplementation in diabetic mice. Importantly, strawberry supplementation increased the abundance of beneficial bacteria Bifidobacterium which play a pivotal role in the metabolism of anthocyanins.


Asunto(s)
Diabetes Mellitus Experimental/microbiología , Fragaria , Microbioma Gastrointestinal/fisiología , Animales , Diabetes Mellitus Experimental/dietoterapia , Suplementos Dietéticos , Masculino , Redes y Vías Metabólicas , Ratones Endogámicos C57BL , Ratones Mutantes , Receptores de Leptina/genética
6.
Exp Biol Med (Maywood) ; 243(8): 695-707, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29763383

RESUMEN

The isoflavone phytoestrogens found in the soy protein isolate used in soy infant formulas have been shown to have estrogenic actions in the developing male reproductive tract resulting in reproductive toxicity. However, few studies have examined potential estrogenicity of soy protein isolate as opposed to that of pure isoflavones. In this study, we fed weanling male Sprague-Dawley rats a semi-purified diet with casein or soy protein isolate as the sole protein source from postnatal day 21 to 33. Additional groups were fed casein or soy protein isolate and treated s.c. with 10 µg/kg/d estradiol via osmotic minipump. Estradiol treatment reduced testis, prostate weights, and serum androgen concentrations ( P < 0.05). Soy protein isolate had no effect. Estradiol up-regulated 489 and down-regulated 1237 testicular genes >1.5-fold ( P < 0.05). In contrast, soy protein isolate only significantly up-regulated expression of 162 genes and down-regulated 16 genes. The top 30 soy protein isolate-up-regulated genes shared 93% concordance with estradiol up-regulated genes. There was little overlap between soy protein isolate down-regulated genes and those down-regulated by estradiol treatment. Functional annotation analysis revealed significant differences in testicular biological processes affected by estradiol or soy protein isolate. Estradiol had major actions on genes involved in reproductive processes including down-regulation of testicular steroid synthesis and expression of steroid receptor activated receptor (Star) and cytochrome P450 17α-hydroxylase/(Cyp17a1). In contrast, soy protein isolate primarily affected pathways associated with macromolecule modifications including ubiquitination and histone methylation. Our results indicate that rather than acting as a weak estrogen in the developing testis, soy protein isolate appears to act as a selective estrogen receptor modulator with little effect on reproductive processes. Impact statement Soy protein isolate (SPI) is the sole protein used to make soy-based infant formulas. SPI contains phytoestrogens, which are structurally similar to estradiol. These phytoestrogens, daidzein, genistein, and equol, fit the definition of endocrine-disrupting compounds, and at high concentrations, have estrogenic actions resulting in reproductive toxicity in the developing male, when provided as isolated chemicals. However, few animal studies have examined the potential estrogenicity of SPI as opposed to pure isoflavones. In this study, SPI feeding did not elicit an estrogenic response in the testis nor any adverse outcomes including reduced testicular growth, or androgen production during early development in rats when compared to those receiving estradiol. These findings are consistent with emerging data showing no differences in reproductive development in males and female children that received breast milk, cow's milk formula, or soy infant formula during the postnatal feeding period.


Asunto(s)
Fitoestrógenos/administración & dosificación , Fitoestrógenos/efectos adversos , Proteínas de Soja/administración & dosificación , Proteínas de Soja/efectos adversos , Testículo/patología , Andrógenos/sangre , Animales , Masculino , Ratas Sprague-Dawley , Suero/química
7.
Physiol Genomics ; 45(22): 1072-83, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24046281

RESUMEN

Isoflavones are phytochemical components of soy diets that bind weakly to estrogen receptors (ERs). To study potential estrogen-like actions of soy in the mammary gland during early development, we fed weanling male and female Sprague-Dawley rats a semipurified diet with casein as the sole protein source from postnatal day 21 to 33, the same diet substituting soy protein isolate (SPI) for casein, or the casein diet supplemented with estradiol (E2) at 10 µg/kg/day. In contrast to E2, the SPI diet induced no significant change in mammary morphology. In males, there were 34 genes for which expression was changed ≥2-fold in the SPI group vs. 509 changed significantly by E2, and 8 vs. 174 genes in females. Nearly half of SPI-responsive genes in males were also E2 responsive, including adipogenic genes. Serum insulin was found to be decreased by the SPI diet in males. SPI and E2 both downregulated the expression of ERα (Esr1) in males and females, and ERß (Esr2) only in males. Chromatin immunoprecipitation revealed an increased binding of ERα to the promoter of the progesterone receptor (Pgr) and Esr1 in both SPI- and E2-treated males compared with the casein group but differential recruitment of ERß. ER promoter binding did not correlate with differences in Pgr mRNA expression. This suggests that SPI fails to recruit appropriate co-activators at E2-inducible genes. Our results indicate that SPI behaves like a selective estrogen receptor modulator rather than a weak estrogen in the developing mammary gland.


Asunto(s)
Estradiol/farmacología , Estrógenos/farmacología , Glándulas Mamarias Animales/efectos de los fármacos , Proteínas de Soja/farmacología , Animales , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/genética , Receptor beta de Estrógeno/metabolismo , Femenino , Expresión Génica , Masculino , Glándulas Mamarias Animales/citología , Glándulas Mamarias Animales/crecimiento & desarrollo , Regiones Promotoras Genéticas , Ratas , Ratas Sprague-Dawley , Factores Sexuales , Destete
8.
PLoS One ; 7(4): e35736, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22536432

RESUMEN

BACKGROUND: Previous reports suggest that beneficial effects of soy on bone quality are due to the estrogenic actions of isoflavone phytochemicals associated with the protein. However, mechanistic studies comparing the effects of soy diet and estrogens on bone, particularly in rapidly growing animals are lacking. METHODOLOGY AND PRINCIPAL FINDINGS: We studied the effects of short term feeding of soy protein isolate (SPI) on bone in comparison to the effects of 17ß-estradiol (E2) in pre-pubertal rats. Female rats were weaned to one of 4 treatments: 1) a control casein-based diet (CAS); 2) CAS with subcutaneous E2 (10 µg/kg/d) (CAS+E2); 3) a SPI-containing diet (SPI); or 4) SPI with subcutaneous E2 (SPI) or SPI with 10 µg/kg/d E2 (SPI+E2) for 14 days beginning on postnatal day 20. SPI increased while E2 decreased bone turnover compared to CAS. In contrast, both treatments decreased serum sclerostin levels. Microarray analysis of RNA isolated from bone revealed 652 genes regulated by SPI, 491 genes regulated by E2, and 266 genes regulated by both SPI diet and E2 compared to CAS. The expression of caveolin-1, a protein localized in the cell membrane, was down-regulated (p<0.05) in rats fed SPI, but not by E2 compared to rats fed casein. Down-regulation of caveolin-1 by SPI was associated with increased BMP2, Smad and Runx2 expression in bone and osteoblasts (p<0.05). CONCLUSIONS/SIGNIFICANCE: These results suggest SPI and E2 have different effects on bone turnover prior to puberty. Approximately half of the genes are regulated in the same direction by E2 or SPI, but in combination, SPI blocks the estrogen effects and returns the profile towards control levels. In addition, there are E2 specific and SPI-specific gene changes related to regulation of bone formation.


Asunto(s)
Huesos/metabolismo , Proteínas en la Dieta/administración & dosificación , Estradiol/farmacología , Proteínas de Soja/administración & dosificación , Factor de Transcripción Activador 3/genética , Factor de Transcripción Activador 3/metabolismo , Fosfatasa Alcalina/sangre , Animales , Proteína Morfogenética Ósea 2/genética , Proteína Morfogenética Ósea 2/metabolismo , Proteínas Morfogenéticas Óseas/genética , Proteínas Morfogenéticas Óseas/metabolismo , Resorción Ósea/sangre , Huesos/efectos de los fármacos , Calcitonina/genética , Calcitonina/metabolismo , Caveolina 1/genética , Caveolina 1/metabolismo , Diferenciación Celular/efectos de los fármacos , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Femenino , Perfilación de la Expresión Génica , Marcadores Genéticos/genética , Isoflavonas/sangre , Análisis de Secuencia por Matrices de Oligonucleótidos , Osteoblastos/efectos de los fármacos , Osteoblastos/fisiología , Osteocalcina/sangre , Ratas , Ratas Sprague-Dawley , Maduración Sexual , Transducción de Señal , Transcripción Genética/efectos de los fármacos
9.
J Endocrinol ; 202(1): 141-52, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19372191

RESUMEN

Although soy foods have been recognized as an excellent source of protein, there have been recent concerns regarding potential adverse effects of isoflavone phytochemicals found in soy products, which are known to bind and activate estrogen receptors. Here, we used global hepatic gene expression profiles in ovariectomized female Sprague-Dawley rats treated with 17beta-estradiol (E(2)) or fed with soy protein isolate (SPI) as a means of estimating potential estrogenicity of SPI. Female Sprague-Dawley rats were fed AIN-93G diets containing casein (CAS) or SPI starting at postnatal day (PND) 30. Rats were ovariectomized on PND 50 and infused with E(2) or vehicle in osmotic pumps for 14 d. Microarray analysis was performed on liver using Affymetrix GeneChip Rat 230 2.0. Serum E(2) levels were within normal ranges for the rat and SPI feeding did not increase uterine wet weight in the absence or presence of E(2). SPI feeding altered (P<0.05, >or=+/-1.5-fold) the expression of 82 genes, while E(2) treatment altered 892 genes. Moreover, only 4% of E(2)-affected genes were also modulated by SPI, including some whose expression was reversed by SPI feeding. The interaction between E(2) and SPI uniquely modulated the expression profile of 225 genes including the reduction of those involved in fatty acid biosynthesis or glucocorticoid signaling and an induction of those involved in cholesterol metabolism. The different hepatic gene signatures produced by SPI feeding compared with E(2) and the lack of increase in uterine wet weight in rats fed with SPI suggest that SPI is not estrogenic in these tissues.


Asunto(s)
Estradiol/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Hígado/efectos de los fármacos , Proteínas de Soja/farmacología , Animales , Ingestión de Alimentos/fisiología , Estradiol/sangre , Femenino , Perfilación de la Expresión Génica , Isoflavonas/sangre , Hígado/anatomía & histología , Hígado/metabolismo , Tamaño de los Órganos/efectos de los fármacos , Ovariectomía , Ratas , Ratas Sprague-Dawley , Proteínas de Soja/aislamiento & purificación , Útero/anatomía & histología , Útero/efectos de los fármacos
10.
J Nutr ; 138(10): 1872-9, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18806095

RESUMEN

A "2-hit" model for nonalcoholic steatohepatitis (NASH) has been proposed in which steatosis constitutes the "first hit" and sensitizes the liver to potential "second hits" resulting in NASH. Oxidative stress is considered a candidate for the second hit. N-acetylcysteine (NAC), an antioxidant, has been suggested as a dietary therapy for NASH. We examined the effects of NAC in a rat total enteral nutrition (TEN) model where NASH develops as the result of overfeeding dietary polyunsaturated fat. Male Sprague-Dawley rats consumed pelleted AIN-93G diets ad libitum or were overfed a 9200 kJ.kg(-0.75).d(-1) liquid diet containing 70% corn oil with or without 2 g.kg(-1).d(-1) NAC i.g. for 65 d. Hepatic steatosis was not influenced by dietary supplementation with NAC; however, the liver pathology score was lower (P

Asunto(s)
Acetilcisteína/farmacología , Hígado Graso/patología , Hígado Graso/prevención & control , Hígado/patología , Animales , Autoanticuerpos/sangre , Modelos Animales de Enfermedad , Ingestión de Energía , Hígado Graso/inmunología , Hígado Graso/fisiopatología , Glutatión/metabolismo , Inflamación , Hígado/efectos de los fármacos , Hígado/metabolismo , Pruebas de Función Hepática , Masculino , Estrés Oxidativo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Triglicéridos/sangre
11.
Am J Physiol Gastrointest Liver Physiol ; 294(1): G27-38, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17947452

RESUMEN

We have used total enteral nutrition (TEN) to moderately overfeed rats high-polyunsaturated fat diets to develop a model for nonalcoholic steatohepatitis (NASH). Male Sprague-Dawley rats were fed by TEN a 187 kcal.kg(-3/4).day(-1) diet containing 5% (total calories) corn oil or a 220 kcal.kg(-3/4).day(-1) diet in which corn oil constituted 5, 10, 25, 35, 40, or 70% of total calories for 21 or 65 days. Rats fed the 5% corn oil, 220 kcal.kg(-3/4).day(-1)diet had greater body weight gain (P < or = 0.05), fat mass (P < or = 0.05), and serum leptin and glucose levels (P < or = 0.05), but no liver pathology. A dose-dependent increase in hepatic triglyceride deposition occurred with increase in percent corn oil in the 220 kcal.kg(-3/4).day(-1) groups (P < or = 0.05). Steatosis, macrophage infiltration, apoptosis, and focal necrosis were present in the 70% corn oil group, accompanied by elevated serum alanine aminotransferase (ALT) levels (P < or = 0.05). An increase in oxidative stress (thiobarbituric acid-reactive substances) and TNF-alpha expression (P < or = 0.05) was observed in the 70% corn oil group, as well as an increase in hepatic CYP2E1 and CYP4A1 expression (P < or = 0.05). Significant positive correlations were observed between the level of dietary corn oil and the degree of pathology, ALTs, oxidative stress, and inflammation. Liver pathology was progressive with increased necrosis, accompanied by fibrosis, observed after 65 days of TEN. Increased expression of CD36 and l-fabp mRNA suggested development of steatosis was associated with increased fatty acid transport. These data suggest that intragastric infusion of a high-polyunsaturated fat diet at a caloric level of 17% excess total calories results in pathology similar to clinical NASH.


Asunto(s)
Aceite de Maíz/administración & dosificación , Modelos Animales de Enfermedad , Hígado Graso/etiología , Hígado , Hipernutrición/complicaciones , Nutrición Parenteral Total , Adiposidad , Alanina Transaminasa/sangre , Animales , Apoptosis , Glucemia/metabolismo , Peso Corporal , Antígenos CD36/análisis , Citocromo P-450 CYP2E1/biosíntesis , Citocromo P-450 CYP4A/biosíntesis , Inducción Enzimática , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Ácidos Grasos/metabolismo , Hígado Graso/genética , Hígado Graso/metabolismo , Hígado Graso/patología , Leptina/sangre , Hígado/enzimología , Hígado/metabolismo , Hígado/patología , Macrófagos/patología , Masculino , Necrosis , Hipernutrición/genética , Hipernutrición/metabolismo , Hipernutrición/patología , Estrés Oxidativo , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Factores de Tiempo , Triglicéridos/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
12.
Toxicol Pathol ; 31(6): 604-18, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14585728

RESUMEN

Our earlier studies with S-(1,2-dichlorovinyl)-L-cysteine (DCVC) showed that prior administration of a low priming dose of 15 mg/kg, i.p. to mice, given 72 hours before administration of a normally lethal dose of DCVC (75 mg/kg, i.p.) led to renal tubule necrosis, however sustained renal tubule regeneration was observed and these mice recovered from renal failure and survived. The objective of the present study was to investigate the role of extracellular signal-regulated kinase (ERK) pathway in this autoprotection model. Following the priming dose of DCVC, IL-6 protein and mRNA increased markedly as early as 1 hour after dosing, peaking at 3 hours with a 1.5-fold increase in plasma. Immunocytochemistry on kidney sections using specific antibodies against TGF-alpha, HB-EGF, EGFr, IGF-1Rbeta, Grb-2, and phospho-p44/42 MAP kinase (ERK1/2) revealed a significantly higher staining of these molecules 3 to 72 hours after dosing, indicating up regulation of the ERK pathway. Following a lethal dose of DCVC (75 mg/kg) the early increase in these signaling molecules was not sustained, being markedly reduced 24 and 36 hours after dosing, leading to inhibition of S-phase DNA synthesis, cell division and renal tubule repair. In contrast, prior treatment with a low dose of DCVC, followed by a high dose led to a sustained stimulation of the renal ERK pathway, renal tubule regeneration and recovery from acute renal failure. These results suggest that a sustained activation of the ERK1/2 pathway may be a key factor in enabling a continued renal tubule repair and hence protection from the progressive phase of DCVC-induced acute renal tubular necrosis in the mouse.


Asunto(s)
Cisteína/análogos & derivados , Necrosis Tubular Aguda/enzimología , Riñón/enzimología , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Recuperación de la Función/fisiología , Animales , Biomarcadores/análisis , Cisteína/toxicidad , Replicación del ADN/efectos de los fármacos , Modelos Animales de Enfermedad , Técnica del Anticuerpo Fluorescente Indirecta , Técnicas para Inmunoenzimas , Interleucina-6/metabolismo , Riñón/efectos de los fármacos , Riñón/patología , Necrosis Tubular Aguda/inducido químicamente , Necrosis Tubular Aguda/patología , Masculino , Ratones , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos , Proteínas Quinasas Activadas por Mitógenos/genética , ARN Mensajero/metabolismo , Recuperación de la Función/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Fase S/efectos de los fármacos
13.
Toxicol Appl Pharmacol ; 188(2): 110-21, 2003 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-12691729

RESUMEN

S-(1,2-dichlorovinyl)-L-cysteine (DCVC), a metabolite of a common environmental contaminant, trichloroethylene, is a selective proximal tubular nephrotoxicant. The objective of our study was to examine the dose-response relationship of renal injury and repair following DCVC administration. Male Swiss-Webster mice were injected with DCVC [15, 30, or 75 mg/kg ip in distilled water (10 ml/kg)] and the extent of nephrotoxicity and tissue repair was assessed over a 14-day period. The renal injury due to the low and medium doses of DCVC peaked at 36 and 72 h after dosing, respectively, and then regressed over time due to a timely and adequate tissue repair response. At the highest dose tissue repair was inhibited, thereby causing progression of renal injury, which led to acute renal failure and death of the mice. The possibility that compromised tissue repair was a result of the extensive nephrotoxic injury attendant to the high dose of DCVC was investigated via an equinephrotoxicity study in which separate groups of mice received 40 (LD40) and 75 (LD90) mg DCVC/kg, respectively. Bioactivation-based renal proximal tubular injury measured in these two groups over a time course was identical but there was a marked difference in mortality due to an early and robust tissue repair in the first group relative to the second group. These results support the concept that quantitative evaluation of renal tissue repair in parallel with injury is useful in the assessment of the likely toxic outcome associated with exposure to nephrotoxic drugs and toxicants.


Asunto(s)
Cisteína/análogos & derivados , Cisteína/toxicidad , Enfermedades Renales/inducido químicamente , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Relación Dosis-Respuesta a Droga , Enzimas/sangre , Glucosa/metabolismo , Riñón/patología , Enfermedades Renales/mortalidad , Enfermedades Renales/patología , Cinética , Hígado/patología , Masculino , Ratones , Antígeno Nuclear de Célula en Proliferación/biosíntesis , Regeneración
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA