RESUMEN
SCOPE: Although prenatal high-salt (HS) intake leads to physiological complications in the offspring, little is known regarding its effects on the offspring's glucose metabolism. Therefore, the objectives of this study are to determine the consequences of prenatal HS diet on the offspring's metabolism and to test a potential therapy. METHODS AND RESULTS: Pregnant rats are fed either a normal-salt (1% NaCl) or high-salt (8% NaCl) diet during the whole pregnancy. Experiments are conducted in five-month-old male offspring. It is found that the prenatal HS diet reduced the glucose tolerance and insulin sensitivity of the offspring. Additionally, there is down-regulation of peroxisome proliferator-activated receptor gamma coactivator 1 alpha (Ppargc1a/PPARGC1A) at the transcript and protein level, which leads to decreased mitochondrial biogenesis and oxidative respiration in skeletal muscle. Moreover, the down-regulation of Ppargc1a is accompanied by decreases in the expression of glucose transporter type 4 (Glut4). With endurance exercise training, these changes are mitigated, which ultimately resulted in improved insulin resistance. CONCLUSION: These findings suggest that prenatal HS intake induces metabolic disorders via the decreased expression of Ppargc1a in the skeletal muscle of adult offspring, providing novel information concerning the mechanisms and early prevention of metabolic diseases of fetal origins.
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Enfermedades Metabólicas/etiología , Músculo Esquelético/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Efectos Tardíos de la Exposición Prenatal/etiología , Cloruro de Sodio Dietético/efectos adversos , Animales , Dieta/efectos adversos , Entrenamiento Aeróbico , Femenino , Transportador de Glucosa de Tipo 4/genética , Resistencia a la Insulina , Masculino , Enfermedades Metabólicas/terapia , Mitocondrias Musculares/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Condicionamiento Físico Animal , Embarazo , Ratas Sprague-DawleyRESUMEN
As a common complication of pregnancy, gestational hypoxia has been shown to predispose offspring to vascular dysfunction. Propionate, one of short-chain fatty acids, exerts cardioprotective effects via reducing blood pressure. This study examined whether prenatal hypoxia impaired propionate-stimulated large-conductance Ca2+ -activated K+ (BK) channel activities in vascular smooth muscle cells (VSMCs) of offspring. Pregnant rats were exposed to hypoxia (10.5% oxygen) and normoxia (21% oxygen) from gestational day 7-21. At 6 weeks of age, VSMCs in mesenteric arteries of offspring were analysed for BK channel functions and gene expressions. It was shown firstly that propionate could open significantly BK single channel in VSMCs in a concentration-dependent manner. Antagonists of G protein ßγ subunits and inositol trisphosphate receptor could completely suppress the activation of BK by propionate, respectively. Gαi/o and ryanodine receptor were found to participate in the stimulation on BK. Compared to the control, vasodilation and increments of BK NPo (the open probability) evoked by propionate were weakened in the offspring by prenatal hypoxia with down-regulated Gßγ and PLCß. It was indicated that prenatal hypoxia inhibited propionate-stimulated BK activities in mesenteric VSMCs of offspring via reducing expressions of Gßγ and PLCß, in which endoplasmic reticulum calcium release might be involved.
Asunto(s)
Hipoxia/tratamiento farmacológico , Canales de Potasio de Gran Conductancia Activados por el Calcio/genética , Complicaciones Cardiovasculares del Embarazo/tratamiento farmacológico , Efectos Tardíos de la Exposición Prenatal/tratamiento farmacológico , Propionatos/farmacología , Animales , Presión Sanguínea/efectos de los fármacos , Señalización del Calcio/efectos de los fármacos , Femenino , Subunidades beta de la Proteína de Unión al GTP/genética , Humanos , Hipoxia/complicaciones , Hipoxia/genética , Hipoxia/patología , Receptores de Inositol 1,4,5-Trifosfato/genética , Arterias Mesentéricas/efectos de los fármacos , Arterias Mesentéricas/patología , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/patología , Fosfolipasa C beta/genética , Embarazo , Complicaciones Cardiovasculares del Embarazo/genética , Complicaciones Cardiovasculares del Embarazo/patología , Efectos Tardíos de la Exposición Prenatal/genética , Efectos Tardíos de la Exposición Prenatal/metabolismo , Efectos Tardíos de la Exposición Prenatal/patología , RatasRESUMEN
Cerebral circulation is important in fetal brain development, and angiotensin II (Ang II) plays vital roles in regulation of adult cerebral circulation. However, functions of Ang II in fetal cerebral vasculature and influences of in utero hypoxia on Ang II-mediated fetal cerebral vascular responses are largely unknown. This study investigated the effects and mechanisms of in utero hypoxia on fetal middle cerebral arteries (MCA) via Ang II. Near-term ovine fetuses were exposed to in utero hypoxia, and fetal MCA responses to Ang II were tested for vascular tension, calcium transient, and molecular analysis. Ang II caused significant dose-dependent contraction in control fetal MCA. Ang II-induced MCA constriction was decreased significantly in hypoxic fetuses. Neither losartan (AT1R antagonist, 10-5 mol/L) nor PD123,319 (AT2R antagonist, 10-5 mol/L) altered Ang II-mediated contraction in fetal MCA. Phenylephrine-mediated constriction was also significantly weaker in hypoxic fetuses. Bay K8644 caused similar contractions between the two groups. Protein expression of L-type voltage-dependent calcium channels was unchanged. There were no differences in caffeine-mediated vascular tension or calcium transients. Contraction induced by PDBu (PKC agonist) was obviously weaker in hypoxic MCA. Protein expression of PKCß was reduced in the hypoxic compared with the control, along with no differences in phosphorylation levels. The results showed that fetal MCA was functionally responsive to Ang II near term. Intrauterine hypoxia reduced the vascular agonist-mediated contraction in fetal MCA, probably via decreasing PKCß and its phosphorylation, which might play protective effects on fetal cerebral circulation against transient hypoxia.
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Angiotensina II/farmacología , Feto/irrigación sanguínea , Hipoxia/embriología , Proteína Quinasa C beta/metabolismo , Contracción Uterina/efectos de los fármacos , Animales , Femenino , Arteria Cerebral Media/embriología , Fosforilación/efectos de los fármacos , Embarazo , OvinosRESUMEN
Glucocorticoid receptor (GR) signaling is critical for development and function of the heart. Our previous study demonstrated that gestational hypoxia induced epigenetic repression of the GR gene in the developing heart. The present study aims to determine that the alterations of promoter methylation level and epigenetic repression of the GR gene in the developing heart in response to maternal hypoxia is sustained in adult offspring and potential gender differences in the programming of GR gene. Pregnant rats were treated with 10.5% O2 from gestational day 15 (E15) to 21 (E21). Hearts were isolated from 5-month-old male and female offspring with the developing stage being equivalent to 18-year-old human. GR mRNA and protein abundance was determined with real time qRT-PCR and Western blot. GR gene promoter methylation and binding of transcription factors were measured with methylated DNA immunoprecipitation (MeDIP) and Chromatin immunoprecipitation (ChIP). The results showed that antenatal hypoxia significantly decreased the expression of GR mRNA and protein in the hearts of adult male offspring, but not in females, which is ascribed to the differential changes of alternative exon1 mRNA variants of GR gene in male and female hearts in response to prenatal hypoxia. In addition, the downregulation of GR expression in the male heart was correlated with increased methylation levels of CpG dinucleotides in promoters of exon 14, 15, 16, 17, and 110, which resulted in a decrease in the binding of their transcription factors. Thus, the study reveals that antenatal hypoxia results in a reprogramming and long-term change in GR gene expression in the heart by hypermethylation of GR promoter in a sex-differential pattern, which provides a novel mechanism regarding the increased vulnerability of heart later in life with exposure of prenatal hypoxia.
RESUMEN
AIMS: High-salt diet is linked to hypertension, and prenatal high-salt diet increases the risk of cardiovascular diseases in the offspring. The present study investigated whether and how prenatal high-salt diet influenced nitric oxide-mediated vasodilatation in the offspring. METHODS AND RESULTS: Pregnant rats were fed either normal-salt (1% sodium chloride) or high-salt (8% sodium chloride) diet during gestation. Experiments were conducted in 5-month-old male offspring. Sodium nitroprusside (SNP, nitric oxide donor)-induced hypotensive responses (in vivo) and vascular dilatation (in vitro) was significantly attenuated (Emax: 84â±â2 vs. 51â±â2, high-salt vs. control, Pâ<â0.001) in the high-salt offspring, indicating reduced vascular relaxations. Pretreatment with Tempol (reactive oxygen species scavenger) alleviated this attenuation. The high-salt offspring showed an increased level of oxidative stress markers in both mesenteric arteries and plasma samples. The antioxidant activity, serum superoxide dismutase and catalase were significantly reduced, whereas malondialdehyde was increased in the high-salt offspring. O2 production, and protein expression of Nox2 and Nox4 in mesenteric arteries was significantly increased in the high-salt offspring whereas Nox1 showed no changes. The local renin-angiotensin system in mesenteric arteries was activated, associated with an increased NADPH oxidase. DNA methylation at the proximal promoter of angiotensin-converting enzyme gene in the lung was significantly increased in the high-salt offspring (Pâ=â0.004). CONCLUSION: The results suggest that prenatal high-salt diet impairs nitric oxide-mediated vasodilatation because of the increased oxidative stress-affected renin-angiotensin system in the high-salt offspring, providing new information for understanding, and early prevention of cardiovascular diseases in fetal origins.
Asunto(s)
Efectos Tardíos de la Exposición Prenatal/fisiopatología , Sistema Renina-Angiotensina , Cloruro de Sodio Dietético/efectos adversos , Vasodilatación , Animales , Antioxidantes/farmacología , Catalasa/sangre , Óxidos N-Cíclicos/farmacología , Metilación de ADN , Femenino , Hipotensión/inducido químicamente , Hipotensión/fisiopatología , Masculino , Malondialdehído/sangre , Arterias Mesentéricas/metabolismo , NADPH Oxidasa 1/metabolismo , NADPH Oxidasa 2/metabolismo , NADPH Oxidasa 4/metabolismo , NADPH Oxidasas/metabolismo , Óxido Nítrico/metabolismo , Donantes de Óxido Nítrico/farmacología , Nitroprusiato/farmacología , Estrés Oxidativo/efectos de los fármacos , Peptidil-Dipeptidasa A/genética , Embarazo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Ratas , Cloruro de Sodio Dietético/administración & dosificación , Marcadores de Spin , Superóxido Dismutasa/sangre , Vasodilatación/efectos de los fármacosRESUMEN
Background: Adverse stress exposure during the early neonatal period has been shown to cause aberrant development, resulting in an increased risk of adult disease. We tested the hypothesis that neonatal exposure to lipopolysaccharide (LPS) does not alter heart function at rest condition but causes heart dysfunction under stress stimulation later in life. Methods: Saline control or LPS were administered to neonatal rats via intraperitoneal injection. Experiments were conducted in 6 week-old male and female rats. Isolated hearts were perfused in a Langendorff preparation. Results: Neonatal LPS exposure exhibited no effects on the body weight of the developing rats, but induced decreases in the left ventricle (LV) to the body weight ratio in male rats. Neonatal LPS exposure showed no effects on the baseline heart function determined by in vivo and ex vivo experiments, but caused decreases in the post-ischemic recovery of the LV function in male but not female rats. Neonatal LPS-mediated LV dysfunction was associated with an increase in myocardial infarct size and the LDH release in the male rats. Conclusion: The present study provides novel evidence that neonatal immune challenges could induce gender-dependent long-term effects on cardiac development and heart function, which reinforces the notion that adverse stress exposure during the early neonatal period can aggravate heart functions and the development of a heart ischemia-sensitive phenotype later in life.
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Corazón/fisiopatología , Lipopolisacáridos/toxicidad , Infarto del Miocardio/fisiopatología , Daño por Reperfusión Miocárdica/fisiopatología , Daño por Reperfusión/fisiopatología , Animales , Animales Recién Nacidos , Modelos Animales de Enfermedad , Corazón/efectos de los fármacos , Humanos , Masculino , Infarto del Miocardio/inducido químicamente , Daño por Reperfusión Miocárdica/inducido químicamente , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/inducido químicamente , Caracteres SexualesRESUMEN
SCOPE: High salt (HS) diets are related to cardiovascular diseases, and prenatal HS was suggested to increase risks of coronary artery diseases in the offspring. This study tested the hypothesis that prenatal HS may influence Adenosine-induced vasodilatation via protein kinase A (PKA) pathway in coronary arteries. METHODS AND RESULTS: Sprague-Dawley rats were fed with 8% salt diet for gestation, the control was fed with 0.3% salt diet. Coronary arteries from male adult offspring were tested for K+ channels and Adenosine signal pathways. Adenosine-mediated vasodilatation was reduced in coronary arteries in HS. There was no difference in gene expression of A2A receptors between the two groups. After pretreatment with PKA inhibitor, vasodilatation to Adenosine was decreased to a smaller extent in HS than that in control. Forskolin (activator of adenylate cyclase)-mediated vasodilatation was decreased in HS. Iberiotoxin (large-conductance Ca2+ -activated K+ channel [BK channel] inhibitor) attenuated Forskolin-induced vasodilatation in control, not in HS group. Currents of BK channels decreased in coronary artery smooth muscle cells, and PKA-modulated BK channel functions were declined. Protein levels of BK ß1 and PKA C-subunits in coronary arteries of HS offspring were reduced. CONCLUSIONS: Prenatal HS diets altered Adenosine-mediated coronary artery vasodilatation in the offspring, which was linked to downregulation of cAMP/PKA/BK channel pathway.
Asunto(s)
Adenosina/metabolismo , Vasos Coronarios/efectos de los fármacos , Cloruro de Sodio Dietético/farmacología , Vasodilatación/efectos de los fármacos , Adenosina/farmacología , Animales , Animales Recién Nacidos , Vasos Coronarios/metabolismo , AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Femenino , Canales de Potasio de Gran Conductancia Activados por el Calcio/metabolismo , Masculino , Fenómenos Fisiologicos Nutricionales Maternos , Músculo Liso Vascular/citología , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Embarazo , Efectos Tardíos de la Exposición Prenatal , Ratas Sprague-Dawley , Receptor de Adenosina A2A/metabolismo , Transducción de SeñalRESUMEN
OBJECTIVE: To explore associations between maternal and fetal vitamin D status in preeclamptic pregnancies. METHODS: A case-control experiment was carried out with proportion ratio of 1:1 (controls: n = 60 vs cases: n = 60). Blood collection of both maternal and cord were performed before and during delivery, respectively, and 25(OH)D measurement was conducted. Difference analysis was performed according to returned data. Immunohistochemical analysis, together with semi-quantitative Western blot, was also performed to determine protein expression of vitamin D receptor in placenta and cord tissues of ESPE. RESULTS: Mean ± SD values of maternal 25(OH)D in control and PE group were 38.06 ± 6.28 and 33.05 ± 4.10, respectively, and significant differences with P < 0.0001 were found between control and PE in both continuous and categorical variables, especially in ESPE subtype (32.96 ± 4.49). The deficiency category (< 30 nmol/L) showed increased odds of PE (OR, 2.83, 95% CI, 1.32-6.08) in both maternal 25(OH)D and cord 25(OH)D in multivariable logistic regression. Semi-quantitative analysis showed that expression of placenta VDR in the ESPE subgroup was significantly higher than that in control group with P < 0.001, while expression of umbilical vein VDR in ESPE subgroup was significantly higher than that in control group with P < 0.05. CONCLUSIONS: The present study finds that lowest maternal and fetal vitamin D status in ESPE existed in the preeclampsia subsets. The VDR expression in placenta and fetus in ESPE were higher than that of normal pregnancy, which indicated that it might be related to placenta compensatory mechanism and is worthy of further research.
RESUMEN
Melatonin is involved in the regulation of blood pressure through the receptor dependent or independent route. However, the effect of melatonin on fetal blood pressure is unknown. This study investigated the effect of melatonin on blood pressure of the late-term ovine fetus in utero. Melatonin and/or antagonists were intravenously administered into the fetuses. Mean arterial pressure and heart rate were recorded. Fetal blood samples were analyzed for biochemical parameters and hormones, including cortisol, angiotensin I, angiotensin II, aldosterone, atrial natriuretic peptide, corticotrophin-releasing hormone, adrenocorticotropic hormone, and endothelin. Fetal blood pressure was decreased following administration of melatonin, whereas it was increased following administration of luzindole, but not prazosin. Plasma level of endothelin was decreased by melatonin, which was blocked by luzindole. Our study suggested that melatonin reduced fetal blood pressure via MT1/MT2 receptors and possibly involving release of endothelin.
Asunto(s)
Presión Sanguínea/efectos de los fármacos , Melatonina/farmacología , Receptor de Melatonina MT1/antagonistas & inhibidores , Receptor de Melatonina MT2/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Antagonistas de Receptores Adrenérgicos alfa 1/farmacología , Hormona Adrenocorticotrópica/sangre , Aldosterona/sangre , Angiotensina I/sangre , Angiotensina II/sangre , Animales , Factor Natriurético Atrial/sangre , Hormona Liberadora de Corticotropina/sangre , Endotelinas/sangre , Feto/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Hidrocortisona/sangre , Prazosina/farmacología , Ovinos , Oveja Doméstica , Triptaminas/farmacologíaRESUMEN
Although a large number of studies show that photo-period disruption potentially affects hormone secretion in mammals, information about the effects of circadian photo-period disruption during pregnancy on fetal blood reproductive hormone levels is scarce. This study used ewes and their fetuses to determine the effects of circadian photo-period disruption (deprivation of darkness) on follicle-stimulating hormone, luteinizing hormone, estradiol, and progesterone in maternal and fetal circulation at late gestation. Pregnant ewes (gestational age: 135 ± 3 days) were randomly placed into control and dark deprivation groups. The control (N = 5) and dark deprivation (N = 5) groups were exposed to a fixed 12 h light/12 h dark cycle and a 24 h constant light cycle, respectively, for 2 days. Dark deprivation up-regulated follicle-stimulating hormone and estradiol levels and down-regulated progesterone levels in both maternal and fetal circulation, and up-regulated luteinizing hormone levels in fetal but not maternal circulation. These results provide new information about how circadian photo-period disruption during pregnancy could alter the release of certain reproductive hormones into fetal blood, which may influence the development of fetal organs in utero, as well as long-term health.
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Ritmo Circadiano , Estradiol/sangre , Hormona Folículo Estimulante/sangre , Hormona Luteinizante/sangre , Fotoperiodo , Progesterona/sangre , Animales , Femenino , Sangre Fetal , Regulación del Desarrollo de la Expresión Génica , Embarazo , Preñez , Radioinmunoensayo , Distribución Aleatoria , Ovinos , Oveja DomésticaRESUMEN
SCOPE: High-salt diet (HSD) is associated with cardiovascular diseases. This study aims at ascertaining the influence of maternal HSD on offspring's angiotensin II (ANG II)-mediated vasoconstriction and the underlying mechanisms. METHODS AND RESULTS: In comparison to a normal-salt diet, HSD used in pregnancy in rats changed the ultrastructures of the coronary artery (CA) in 5-month-old male offspring, and increased ANG II-mediated CA contractility. Measurement of [Ca(2+) ]i in CA using fluorescent fura-2, a Ca(2+) indicator, showed that ANG II-mediated increases in [Ca(2+) ]i were the same between HSD and normal-salt diet groups, but the ratio of diameter change/[Ca(2+) ]i induced by ANG II were significantly higher in HSD groups. Angiotensin II receptor type 1, not angiotensin II receptor type 2, caused ANG II-mediated vasoconstriction. Protein kinase C (PKC) inhibitor GF109203X attenuated the ANG II-mediated vasoconstriction, PKC agonist phorbol12,13-dibutyrate produced a greater contraction. There was an increase in PKCß mRNA and the corresponding protein abundance in the offspring, whereas other PKC subunits PKCα, PKCδ, and PKCε did not change. Moreover, 20 kDa myosin light chain phosphorylation levels were increased in HSD group. CONCLUSION: Maternal HSD affected the developmental programing for the offspring CA, with increased ANG II-mediated vasoconstrictions. The angiotensin II receptor type 1-PKC-20 kDa myosin light chain phosphorylation pathway was the possible mediated cellular mechanism.
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Fenómenos Fisiologicos Nutricionales Maternos , Efectos Tardíos de la Exposición Prenatal/genética , Receptor de Angiotensina Tipo 1/metabolismo , Cloruro de Sodio Dietético/efectos adversos , Vasoconstricción/efectos de los fármacos , Angiotensina II/sangre , Animales , Aorta Torácica/efectos de los fármacos , Aorta Torácica/metabolismo , Dieta , Femenino , Indoles/farmacología , Masculino , Maleimidas/farmacología , Cadenas Ligeras de Miosina/metabolismo , Forbol 12,13-Dibutirato/farmacología , Fosforilación , Embarazo , Proteína Quinasa C/genética , Proteína Quinasa C/metabolismo , Ratas , Ratas Sprague-Dawley , Receptor de Angiotensina Tipo 1/genética , Renina/sangre , Sistema Renina-Angiotensina/efectos de los fármacos , Transducción de Señal , Sodio/sangreRESUMEN
Adverse prenatal factors such as overtake of salt or fat food are potential risks for cardiovascular diseases in offspring. This study tested the hypothesis that prenatal high-salt (HS) diets may influence renal vascular tone and attenuates signaling pathways related to soluble guanylyl cyclase (sGC) or/and large-conductance Ca(2+)-activated K(+) (BKCa) channels in the offspring. Pregnant rats were fed either normal salt (NS) (1% NaCl) or HS (8% NaCl) diet for the whole gestation. Offspring were maintained on NS diets. Renal interlobar arteries in offspring were tested for vascular responses to phenylephrine (Phe), K(+) channels and signal pathways related to sGC. Phe induced higher vessel tension in interlobar arteries of the HS offspring. Following pretreatment with BKCa channel inhibitor iberiotoxin, Phe-mediated vasoconstrictions were decreased in HS offspring compared to NS. Phe-mediated constrictions following pretreatment with NO synthase inhibitor N(G)-nitro-l-arginine methyl ester or sGC inhibitor 1H-1,2,4-oxadiazolo-4,3-quinoxalin-1-one in the HS offspring were less sensitive than NS. The whole-cell K(+) currents and the component of BKCa channels were not changed in smooth muscle cells from interlobar arteries, whereas the K(+) currents stimulated by sGC activator BAY41-2272 were reduced in the HS offspring. The protein expressions of sGC ß1 and ß2 in the interlobar arteries of HS offspring were reduced. The results showed that chronic overintake of salt during pregnancy could increase renal vascular tone in the offspring. The affected signal pathways included down-regulation of sGC function and expression.
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Guanilato Ciclasa/metabolismo , Riñón/irrigación sanguínea , Receptores Citoplasmáticos y Nucleares/metabolismo , Cloruro de Sodio Dietético/administración & dosificación , Animales , Femenino , Embarazo , Ratas , Guanilil Ciclasa SolubleRESUMEN
Large studies in humans and animals have demonstrated a clear association of an adverse intrauterine environment with an increased risk of cardiovascular disease later in life. Yet mechanisms remain largely elusive. The present study tested the hypothesis that gestational hypoxia leads to promoter hypermethylation and epigenetic repression of the glucocorticoid receptor (GR) gene in the developing heart, resulting in increased heart susceptibility to ischemia and reperfusion injury in offspring. Hypoxic treatment of pregnant rats from day 15 to 21 of gestation resulted in a significant decrease of GR exon 14, 15, 16, and 17 transcripts, leading to down-regulation of GR mRNA and protein in the fetal heart. Functional cAMP-response elements (CREs) at -4408 and -3896 and Sp1 binding sites at -3425 and -3034 were identified at GR untranslated exon 1 promoters. Hypoxia significantly increased CpG methylation at the CREs and Sp1 binding sites and decreased transcription factor binding to GR exon 1 promoter, accounting for the repression of the GR gene in the developing heart. Of importance, treatment of newborn pups with 5-aza-2'-deoxycytidine reversed hypoxia-induced promoter methylation, restored GR expression and prevented hypoxia-mediated increase in ischemia and reperfusion injury of the heart in offspring. The findings demonstrate a novel mechanism of epigenetic repression of the GR gene in fetal stress-mediated programming of ischemic-sensitive phenotype in the heart.
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Epigénesis Genética , Hipoxia/genética , Daño por Reperfusión Miocárdica/genética , Oxígeno/farmacología , Receptores de Glucocorticoides/genética , Factor de Transcripción Sp1/genética , Animales , Animales Recién Nacidos , Azacitidina/análogos & derivados , Azacitidina/farmacología , Sitios de Unión , Metilación de ADN/efectos de los fármacos , Decitabina , Exones , Femenino , Hipoxia/tratamiento farmacológico , Hipoxia/metabolismo , Hipoxia/patología , Masculino , Exposición Materna , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Daño por Reperfusión Miocárdica/prevención & control , Fenotipo , Embarazo , Regiones Promotoras Genéticas , Unión Proteica , Ratas , Ratas Sprague-Dawley , Receptores de Glucocorticoides/antagonistas & inhibidores , Receptores de Glucocorticoides/metabolismo , Elementos de Respuesta , Factor de Transcripción Sp1/metabolismoRESUMEN
BACKGROUND: Hypoxia is a critical contributor to increased risks of cardiovascular diseases, including atherosclerosis, but the detailed mechanism that hypoxia leads to atherosclerosis remains unknown. METHODS: Pregnant rats were treated with hypoxia (10.5% oxygen) during pregnancy, and HUVEC cells treated with 1% of oxygen. Blood lipids were tested at fetal stage and adult stage of offspring rats; the level of pro-inflammatory cytokines of HUVEC and offspring rats were investigated, and HIF-1α and NFκB mRNA level were also measured by Q-PCR and Elisa. RESULTS: We found that TC, LDL-C, ox-LDL-C, and the receptors of ox-LDL-C (lox-1) of the adult offspring were significantly higher than that of the control, while HDL-C was significantly reduced in hypoxia group. The internal elastic lamina was blocked by smooth muscle cells; and the migration of smooth muscle cells into the intima were observed in hypoxia offspring. Luciferase reporter gene experiment showed that HIF-1α activated NFκB transcription at four discrete binding sites of NFκBp65 promoter, although there was no obvious difference among the four discrete binding sites. Using transfection of pCDNA3.1-HIF-1α on HUVEC cells, HIF-1α significantly activated NFκB transcription at hypoxic conditions (1% O2), and concurrent with increased expression of IL-1ß and TNF-α. CONCLUSION: Hypoxia during pregnancy activated NFκB transcription to induce pro-inflammatory cytokines, leading to the early stage of atherosclerosis.
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Aterosclerosis/etiología , Hipoxia/complicaciones , Lípidos/sangre , Preñez , Vasculitis/complicaciones , Animales , Animales Recién Nacidos , Aterosclerosis/sangre , Aterosclerosis/patología , Células Cultivadas , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Hipoxia/sangre , Embarazo , Ratas , Ratas Sprague-Dawley , Vasculitis/sangre , Vasculitis/patologíaRESUMEN
Herbal products have been used as conventional medicines for thousands of years, particularly in Eastern countries. Thousands of clinical and experimental investigations have focused on the effects and mechanisms-of-action of herbal medicine in the treatment of cardiovascular diseases (CVDs). Considering the history of clinical practice and the great potentials of herb medicine and/or its ingredients, a review on this topic would be helpful. This article discusses possible effects of herbal remedies in the prevention and treatment of CVDs. Crucially, we also summarize some underlying pharmacological mechanisms for herb products in cardiovascular regulations, which might provide interesting information for further understanding the effects of herbal medicines, and boost the prospect of new herbal products against CVDs.
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Fármacos Cardiovasculares/farmacología , Enfermedades Cardiovasculares/tratamiento farmacológico , Preparaciones de Plantas/uso terapéutico , Animales , Fármacos Cardiovasculares/aislamiento & purificación , Enfermedades Cardiovasculares/prevención & control , Diseño de Fármacos , Humanos , Medicina Tradicional , Fitoterapia/métodos , Plantas Medicinales/químicaRESUMEN
SCOPE: High-salt (HS) intake is linked to hypertension, and prenatal exposure to maternal HS diets may have long-term impact on cardiovascular systems. The relationship between HS diets and cardiovascular disease has received extensive attention. This study determined pressor responses and microvessel functions in the adult offspring rats exposed to prenatal HS. METHODS AND RESULTS: The offspring of 5-month old as young adults in rats were used. Blood pressure, vascular tone, intracellular Ca(2+), and BK channels in mesenteric arteries were measured in the offspring. Phenylephrine (Phe)-induced pressor responses were significantly higher in the prenatal HS offspring. Vessel tension and intracellular Ca(2+) concentrations associated with Phe-induced pressor responses were increased in the mesenteric arteries of the HS offspring. PKC α- and δ-isoforms were upregulated in mesenteric arteries of the HS offspring. The enhanced Phe-mediated vascular activity was linked to the altered PKC-modulated BK channel functions. CONCLUSION: The results suggested that prenatal exposure to HS altered microvascular activity probably via changes in PKC/BK signaling pathways, which may lead to increased risks of hypertension in the offspring.
Asunto(s)
Canales de Potasio de Gran Conductancia Activados por el Calcio/genética , Proteína Quinasa C/metabolismo , Transducción de Señal , Cloruro de Sodio Dietético/efectos adversos , Vasoconstricción/efectos de los fármacos , Animales , Presión Sanguínea/efectos de los fármacos , Calcio/metabolismo , Dieta , Femenino , Hipertensión/etiología , Hipertensión/patología , Canales de Potasio de Gran Conductancia Activados por el Calcio/metabolismo , Masculino , Fenómenos Fisiologicos Nutricionales Maternos , Arterias Mesentéricas/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Fenilefrina/farmacología , Embarazo , Proteína Quinasa C/genética , Ratas Sprague-Dawley , Regulación hacia ArribaRESUMEN
Hypoxia could stimulate proliferation of mesenchymal stem cells (MSCs) under certain conditions. This study determined angiotensin II mechanisms and PI3K/AKT pathway in hypoxia-induced proliferation of MSCs. Hypoxia (3% oxygen) induced cellular proliferation in mouse MSCs and upregulated endogenous angiotensin II and angiotensin-converting enzyme in the cell culture and expression of AT1 receptors. The expressions of Sox2, not Oct4 and Rex1, were significantly increased by the hypoxia. The blockade of AT1 receptors, not AT2 receptors, depressed hypoxia induced the proliferative effects. Both hypoxia and exogenous angiotensin II activated p-AKT. Moreover, AT1 receptor inhibitor blocked the effects of hypoxia-mediated p-AKT upregulation. The data demonstrated that the hypoxia at 3% oxygen level could induce mouse MSC proliferation, probably as a result of the activation of PI3K signalling pathways via AT1 receptors.
Asunto(s)
Angiotensina II/metabolismo , Hipoxia de la Célula , Proliferación Celular , Células Madre Mesenquimatosas/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Animales , Células Cultivadas , Ratones , Factores de Transcripción/metabolismoRESUMEN
AIMS: Hypoxia has adverse effects on renal development. This study was the first to test hypoxia-induced renal autophagy in rat fetuses. METHODS: Pregnant rats were exposed to hypoxia or normoxia during pregnancy and fetal kidneys were collected at gestation day 21. RESULTS: Fetal kidney weight and ratio of kidney-body weight were reduced. Histological analysis showed enlargement in Bowman space and wider space between interstitia in the kidneys of fetus exposed to hypoxia. Fetal renal B-cell lymphoma 2 (BCL-2) was decreased accompanied with higher 2'-deoxyuridine 5'-triphosphate nick end-labeling staining and unchanged soluble FAS in the hypoxia group. Hypoxia increased autophagic structures, including autophagosomes and autolysosomes, in fetal kidneys and increased renal APG5L. There was an increase in renal LC3-II, Beclin 1, p-S6, hypoxia inducible factor 1α (HIF-1a), and ratio of LC3-II-LC3-I and a decrease in P62, protein kinase B (AKT), and phosphorylated AKT in the hypoxia group. Both renal mammalian target of rapamycin (mTOR) and Beclin 1 signaling were upregulated. CONCLUSION: Hypoxia-affected fetal renal development was associated with renal apoptosis and Beclin 1 signaling-mediated autophagy.
Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Autofagia , Hipoxia/metabolismo , Riñón/metabolismo , Exposición Materna/efectos adversos , Animales , Beclina-1 , Femenino , Edad Gestacional , Hipoxia/complicaciones , Hipoxia/patología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Riñón/ultraestructura , Tamaño de los Órganos , Fosforilación , Embarazo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas Sprague-Dawley , Proteína S6 Ribosómica/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Regulación hacia ArribaRESUMEN
The hippocampus plays a crucial role in learning and memory, and neuronal apoptosis in the hippocampus contributes to learning deficits. Metabolism problems in pregnancy related to excessive fuel consumption (e.g., high fat, high sugar) may influence cognitive and behavioral functions in the offspring by affecting developing brain cells. This study determined the influence of maternal high sucrose (HS) diets on behavior and hippocampal neurons in the young offspring. The ratio of brain weight to body weight in the offspring exposed to prenatal HS diets was significantly decreased; the Morris water maze showed that the offspring exposed to prenatal HS diets exhibited increased escape latencies and path length during navigation testing, while there were no changes in time spent in the target quadrant and number of target approaches. In the offspring exposed to prenatal HS, TUNEL-positive cells were significantly increased in CA1, CA2 and CA3 of the hippocampus; protein expression of insulin-like growth factor-I, PI3K and phosphorylated Akt was significantly decreased, while caspase-3 and N-methyl-d-aspartate receptors were significantly increased in the hippocampus, and there was no change in expression of Bcl-2 and Akt. The results demonstrated that prenatal HS diets could induce the spatial acquisition deficits in the young offspring associated with hippocampal apoptosis, and altered signaling factors for antiapoptosis in the hippocampus might play a critical role in cognition disorders in young children.
Asunto(s)
Apoptosis/efectos de los fármacos , Hipocampo/efectos de los fármacos , Discapacidades para el Aprendizaje/patología , Efectos Tardíos de la Exposición Prenatal , Sacarosa/administración & dosificación , Animales , Glucemia/metabolismo , Femenino , Hipocampo/patología , Tamaño de los Órganos/efectos de los fármacos , Embarazo , Ratas , Ratas Sprague-Dawley , Memoria EspacialRESUMEN
AIMS: Excess salt intake during pregnancy may alter fetal organ structures and functions leading to increased risks in the development of cardiovascular diseases in later life. The present study determined whether and how the prenatal high-salt (HS) diets affect renin-angiotensin system (RAS) that may mediate cardiac cell death. METHODS AND RESULTS: Angiotensin II receptors, AT1 and AT2, protein expression was increased in the myocardium of the offspring exposed to prenatal HS; apoptotic cells appeared in the myocardium of the adult offspring. Mitochondrion was isolated in cell experiments, and the data showed cardiomyocyte apoptosis requiring cytochrome C release. Pretreating H9C2 cells with AT2 agonist CGP42112A induced cell apoptosis in DNA fragments and activated caspase 3. CGP42112A increased mitochondrion cytochrome C release and apoptosis in the cells. CONCLUSION: Both in vitro and in vivo study demonstrated that cardiomyocyte apoptosis was related to AT2 activation. Prenatal HS diets may reprogram RAS that mediates apoptosis in the offspring myocardium, and AT2 may contribute to cardiomyocyte apoptosis via the cytochrome C release pathway.