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1.
Nutr Metab Cardiovasc Dis ; 32(10): 2410-2417, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35872100

RESUMEN

BACKGROUND AND AIMS: We investigated cardiac autonomic function in overweight and obese school-age children. METHODS AND RESULTS: Quantitative cross-sectional study conducted with children (n = 110) of both genders. Children were divided by normal weight (NW; n = 54), overweight (OW; n = 24) and obese (OB; n = 32). Systolic (SBP) and diastolic (DBP) blood pressure and electrocardiograms were recorded and analyzed for heart rate and the heart rate variability (HRV) in time (SDRR, RMSSD, PRR50, SD1 and SD2) and frequency domains (HF, LF and LF/HF). The OB group presented higher SBP (p ≤ 0.01) and DBP (p ≤ 0.01). For HRV, the OB group had a lower PRR50 (p ≤ 0.01) and HF (p ≤ 0.01), associated with higher LF (p ≤ 0.01). Moderate negative correlations were found between the HF, BMI (r = -0.37; p ≤ 0.01) and WC (r = -0.38; p ≤ 0.01). Positive moderate correlation were found between LF, LF/HF and BMI (LF: r = 0.32; p ≤ 0.01; LF/HF: r = 0.31; p ≤ 0.01) and WC (LF: r = 0.34; p ≤ 0.01; LF/HF: = 0.34; p ≤ 0.01). Multiple linear regression showed a positive association between body fat and the SDRR (ß: 0.48; CI: 0.2-4.2; p = 0.02). No differences were observed in cardiac electrical activity. CONCLUSION: Children with obesity but not overweight presented higher blood pressure and cardiac autonomic dysfunction, with sympathetic predominance on the heart rate. This fact was positively correlated with BMI and may be considered an important marker for cardiovascular risk in children.


Asunto(s)
Sistema Nervioso Autónomo , Sobrepeso , Niño , Estudios Transversales , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Obesidad/complicaciones , Obesidad/diagnóstico , Obesidad/epidemiología , Sobrepeso/diagnóstico
2.
Nutr Metab Cardiovasc Dis ; 32(1): 279-289, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34893407

RESUMEN

BACKGROUND AND AIMS: High-fat diet (HFD) intake during gestation and lactation has been associated with an increased risk of developing cardiometabolic disorders in adult offspring. We investigated whether metabolic alterations resulting from the maternal consumption of HFD are prevented by the addition of omega-3 (É·3) in the diet. METHODS AND RESULTS: Wistar rat dams were fed a control (C: 19% of lipids and É·6:É·3 = 12), HF (HF: 33% lipids and É·6:É·3 = 21), or HF enriched with É·3 (HFω3: 33% lipids and É·6:É·3 = 9) diet during gestation and lactation, and their offspring food consumption, murinometric measurements, serum levels of metabolic markers, insulin and pyruvate sensitivity tests were evaluated. The maternal HFD increased body weight at birth, dyslipidemia, and elevated fasting glucose levels in the HF group. The enrichment of É·3 in the maternal HFD led to lower birth weight and improved lipid, glycemic, and transaminase biochemical profile of the HFω3 group until the beginning of adulthood. However, at later adulthood of the offspring, there was no improvement in these biochemical parameters. CONCLUSION: Our findings show the maternal consumption of high-fat É·3-rich diet is able to attenuate or prevent metabolic disruption elicited by HFD in offspring until 90 days old, but not in the long term, as observed at 300 days old of the offspring.


Asunto(s)
Ácidos Grasos Omega-3 , Efectos Tardíos de la Exposición Prenatal , Animales , Dieta Alta en Grasa/efectos adversos , Ácidos Grasos , Femenino , Humanos , Lactancia , Fenómenos Fisiologicos Nutricionales Maternos , Efectos Tardíos de la Exposición Prenatal/etiología , Efectos Tardíos de la Exposición Prenatal/metabolismo , Efectos Tardíos de la Exposición Prenatal/prevención & control , Ratas , Ratas Wistar
3.
Exp Physiol ; 104(9): 1371-1383, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31328309

RESUMEN

NEW FINDINGS: What is the central question of this study? Adrenomedullin in the rostral ventrolateral medulla (RVLM) increases sympathetic activity; given that adrenomedullin is released during hypoxia, what are the effects of its agonism and antagonism in the RVLM after chronic intermitent hypoxia (CIH) exposure? What is the main finding and its importance? CIH exposure sensitizes adrenomedullin-dependent mechanisms in the RVLM, supporting its role as a sympathoexcitatory neuromodulator. A novel mechanism was identified for the generation of sympathetic overdrive and hypertension associated with hypoxia, providing potential guidance on new therapeutic approaches for controlling sympathetic hyperactivity in diseases such as sleep apnoea and neurogenic hypertension. ABSTRACT: Adrenomedullin in the rostral ventrolateral medulla (RVLM) has been shown to increase sympathetic activity whereas the antagonism of its receptors inhibited this autonomic activity lowering blood pressure in conditions of hypertension. Given that hypoxia is a stimulant for releasing adrenomedullin, we hypothesized that the presence of this peptide in the RVLM associated with chronic intermittent hypoxia (CIH) would cause sympathetic overdrive. Juvenile male rats (50-55 g) submitted to CIH (6% oxygen every 9 min, 8 h day-1 for 10 days) were studied in an arterially perfused in situ preparation where sympathetic activity was recorded. In control rats (n = 6), exogenously applied adrenomedullin in the RVLM raised baseline sympathetic activity when combined with episodic activation of peripheral chemoreceptors (KCN 0.05%, 5 times every 5 min). This sympathoexcitatory response was markedly amplified in rats previously exposed to CIH (n = 6). The antagonism of adrenomedullin receptors in the RVLM caused a significant reduction in sympathetic activity in the CIH group (n = 7), but not in controls (n = 8). The transient reflex-evoked sympathoexcitatory response to peripheral chemoreceptor stimulation was not affected by either adrenomedullin or adrenomedullin receptor antagonism in the RVLM of control and CIH rats. Our findings indicate that CIH sensitizes the sympathoexcitatory networks within the RVLM to adrenomedullin, supporting its role as an excitatory neuromodulator when intermittent hypoxia is present. These data reveal novel state-dependent mechanistic insights into the generation of sympathetic overdrive and provide potential guidance on possible unique approaches for controlling sympathetic discharge in diseases such as sleep apnoea and neurogenic hypertension.


Asunto(s)
Adrenomedulina/farmacología , Hipoxia/fisiopatología , Potenciación a Largo Plazo/efectos de los fármacos , Sistema Nervioso Simpático/efectos de los fármacos , Vasoconstrictores/farmacología , Animales , Presión Sanguínea/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Hipertensión/fisiopatología , Masculino , Bulbo Raquídeo/efectos de los fármacos , Bulbo Raquídeo/fisiopatología , Ratas , Síndromes de la Apnea del Sueño/fisiopatología
4.
Clin Exp Pharmacol Physiol ; 43(12): 1177-1184, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27612187

RESUMEN

Maternal protein restriction during pregnancy and lactation predisposes the adult offspring to sympathetic overactivity and arterial hypertension. Although the underlying mechanisms are poorly understood, dysregulation of the oxidative balance has been proposed as a putative trigger of neural-induced hypertension. The aim of the study was to evaluate the association between the oxidative status at transcriptional and functional levels in the medulla oblongata and maternal protein restriction induced-hypertension. Wistar rat dams were fed a control (normal protein; 17% protein) or a low protein ((Lp); 8% protein) diet during pregnancy and lactation, and male offspring was studied at 90 days of age. Direct measurements of baseline arterial blood pressure (ABP) and heart rate (HR) were recorded in awakened offspring. In addition, quantitative RT-PCR was used to assess the mRNA expression of superoxide dismutase 1 (SOD1) and 2 (SOD2), catalase (CAT), glutathione peroxidase (GPx), Glutamatergic receptors (Grin1, Gria1 and Grm1) and GABA(A)-receptor-associated protein like 1 (Gabarapl1). Malondialdehyde (MDA) levels, CAT and SOD activities were examined in ventral and dorsal medulla. Lp rats exhibited higher ABP. The mRNA expression levels of SOD2, GPx and Gabarapl1 were down regulated in medullary tissue of Lp rats (P<.05, t test). In addition, we observed that higher MDA levels were associated to decreased SOD (approximately 45%) and CAT (approximately 50%) activities in ventral medulla. Taken together, our data suggest that maternal protein restriction induced-hypertension is associated with medullary oxidative dysfunction at transcriptional level and with impaired antioxidant capacity in the ventral medulla.


Asunto(s)
Dieta con Restricción de Proteínas/efectos adversos , Hipertensión/metabolismo , Bulbo Raquídeo/metabolismo , Estrés Oxidativo/fisiología , Efectos Tardíos de la Exposición Prenatal/metabolismo , Transcripción Genética/fisiología , Animales , Femenino , Hipertensión/etiología , Masculino , Exposición Materna/efectos adversos , Embarazo , Efectos Tardíos de la Exposición Prenatal/etiología , Distribución Aleatoria , Ratas , Ratas Wistar
5.
J Nutr ; 145(5): 907-14, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25934662

RESUMEN

BACKGROUND: Maternal protein restriction in rats increases the risk of adult offspring arterial hypertension through unknown mechanisms. OBJECTIVES: The aims of the study were to evaluate the effects of a low-protein (LP) diet during pregnancy and lactation on baseline sympathetic and respiratory activities and peripheral chemoreflex sensitivity in the rat offspring. METHODS: Wistar rat dams were fed a control [normal-protein (NP); 17% protein] or an LP (8% protein) diet during pregnancy and lactation, and their male offspring were studied at 30 d of age. Direct measurements of baseline arterial blood pressure (ABP), heart rate (HR), and respiratory frequency (Rf) as well as peripheral chemoreflex activation (potassium cyanide: 0.04%) were recorded in pups while they were awake. In addition, recordings of the phrenic nerve (PN) and thoracic sympathetic nerve (tSN) activities were obtained from the in situ preparations. Hypoxia-inducible factor 1α (HIF-1α) expression was also evaluated in carotid bifurcation through a Western blotting assay. RESULTS: At 30 d of age, unanesthetized LP rats exhibited enhanced resting Rf (P = 0.001) and similar ABP and HR compared with the NP rats. Despite their similar baseline ABP values, LP rats exhibited augmented low-frequency variability (∼91%; P = 0.01). In addition, the unanesthetized LP rats showed enhanced pressor (P = 0.01) and tachypnoeic (P = 0.03) responses to peripheral chemoreflex activation. The LP rats displayed elevated baseline tSN activity (∼86%; P = 0.02) and PN burst frequency (45%; P = 0.01) and amplitude (53%; P = 0.001) as well as augmented sympathetic (P = 0.01) and phrenic (P = 0.04) excitatory responses to peripheral chemoreflex activation compared with the NP group. Furthermore, LP rats showed an increase of ∼100% in HIF-1α protein density in carotid bifurcation compared with NP rats. CONCLUSION: Sympathetic-respiratory overactivity and amplified peripheral chemoreceptor responses, potentially through HIF-1α-dependent mechanisms, precede the onset of hypertension in juvenile rats exposed to protein undernutrition during gestation and lactation.


Asunto(s)
Células Quimiorreceptoras/metabolismo , Dieta con Restricción de Proteínas/efectos adversos , Fenómenos Fisiologicos Nutricionales Maternos , Sistema Nervioso Periférico/fisiopatología , Prehipertensión/fisiopatología , Sistema Respiratorio/fisiopatología , Sistema Nervioso Simpático/fisiopatología , Animales , Peso al Nacer , Arteria Carótida Común/metabolismo , Arteria Carótida Común/patología , Arteria Carótida Común/fisiopatología , Células Quimiorreceptoras/patología , Femenino , Desarrollo Fetal , Retardo del Crecimiento Fetal/etiología , Retardo del Crecimiento Fetal/fisiopatología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Lactancia , Masculino , Sistema Nervioso Periférico/patología , Nervio Frénico/patología , Nervio Frénico/fisiopatología , Embarazo , Prehipertensión/etiología , Prehipertensión/metabolismo , Prehipertensión/patología , Ratas Wistar , Sistema Respiratorio/patología , Sistema Nervioso Simpático/patología , Nervios Torácicos/patología , Nervios Torácicos/fisiopatología
6.
J Physiol ; 592(9): 2013-33, 2014 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-24614747

RESUMEN

Individuals experiencing sustained hypoxia (SH) exhibit adjustments in the respiratory and autonomic functions by neural mechanisms not yet elucidated. In the present study we evaluated the central mechanisms underpinning the SH-induced changes in the respiratory pattern and their impact on the sympathetic outflow. Using a decerebrated arterially perfused in situ preparation, we verified that juvenile rats exposed to SH (10% O2) for 24 h presented an active expiratory pattern, with increased abdominal, hypoglossal and vagal activities during late-expiration (late-E). SH also enhanced the activity of augmenting-expiratory neurones and depressed the activity of post-inspiratory neurones of the Bötzinger complex (BötC) by mechanisms not related to changes in their intrinsic electrophysiological properties. SH rats exhibited high thoracic sympathetic activity and arterial pressure levels associated with an augmented firing frequency of pre-sympathetic neurones of the rostral ventrolateral medulla (RVLM) during the late-E phase. The antagonism of ionotropic glutamatergic receptors in the BötC/RVLM abolished the late-E bursts in expiratory and sympathetic outputs of SH rats, indicating that glutamatergic inputs to the BötC/RVLM are essential for the changes in the expiratory and sympathetic coupling observed in SH rats. We also observed that the usually silent late-E neurones of the retrotrapezoid nucleus/parafacial respiratory group became active in SH rats, suggesting that this neuronal population may provide the excitatory drive essential to the emergence of active expiration and sympathetic overactivity. We conclude that short-term SH induces the activation of medullary expiratory neurones, which affects the pattern of expiratory motor activity and its coupling with sympathetic activity.


Asunto(s)
Fibras Adrenérgicas/fisiología , Presión Sanguínea/fisiología , Frecuencia Cardíaca/fisiología , Hipoxia/fisiopatología , Bulbo Raquídeo/fisiología , Mecánica Respiratoria/fisiología , Animales , Masculino , Técnicas de Cultivo de Órganos , Ratas , Ratas Wistar , Factores de Tiempo
7.
Molecules ; 19(11): 17735-46, 2014 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-25365298

RESUMEN

Simarouba amara stem bark decoction has been traditionally used in Brazil to treat malaria, inflammation, fever, abdominal pain, diarrhea, wounds and as a tonic. In this study, we investigate the hepatoprotective effects of the aqueous extract of S. amara stem bark (SAAE) on CCl4-induced hepatic damage in rats. SAAE was evaluated by high performance liquid chromatography. The animals were divided into six groups (n = 6/group). Groups I (vehicle-corn oil), II (control-CCl4), III, IV, V and VI were pretreated during 10 consecutive days, once a day p.o, with Legalon® 50 mg/kg b.w, SAAE at doses 100, 250 and 500 mg/kg b.w, respectively. The hepatotoxicity was induced on 11th day with 2 mL/kg of 20% CCl4 solution. 24 h after injury, the blood samples were collected and their livers were removed to biochemical and immunohistochemical analyzes. The SAAE decreased the levels of liver markers and lipid peroxidation in all doses and increased the catalase levels at doses 250 and 500 mg/kg. Immunohistochemical results suggested hepatocyte proliferation in all doses. These results may be related to catechins present in SAAE. Thus, SAAE prevented the oxidative damage at the same time that increased regenerative and reparative capacities of the liver.


Asunto(s)
Tetracloruro de Carbono/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Corteza de la Planta/química , Extractos Vegetales/farmacología , Tallos de la Planta/química , Sustancias Protectoras/farmacología , Simarouba/química , Animales , Hígado/efectos de los fármacos , Masculino , Extractos Vegetales/química , Sustancias Protectoras/química , Ratas , Ratas Wistar
8.
Nutr Res ; 118: 104-115, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37634306

RESUMEN

The impact of diets high in saturated fatty acids in individuals who have undergone maternal protein restriction is not clear. Here, we tested the hypothesis that a saturated fatty acid-enriched hyperlipidic diet (HL) affects liver expression of genes of the redox balance and inflammatory pathway in postweaning rat offspring subjected to maternal protein restriction. Pregnant Wistar rats received either a control (C; 19% protein) or low protein (LP; 8% protein) diet during gestation and lactation. At weaning, pups received either C or HL diets up to 90 days of life. The LP+HL group showed an upregulation of transcription of peroxisome proliferator-activated receptor γ (+48%) and peroxisome proliferator-activated receptor γ coactivator α (+96%) compared with the LP+C group (P < .05), respectively. Similarly, gene expression of the markers of inflammation, nuclear factor-kappa B1 (+194%) and tumor necrosis factor-α (+192%), was enhanced (P < .05). Although other antioxidant enzymes were not modified in gene expression, catalase (CAT) was 66% higher in LP+HL compared with LP+C. In contrast, CAT protein content in the liver was 50% lower in LP groups compared with C, and superoxide dismutase 2 (SOD2) was twice as high in LP groups compared with C. Postweaning HL after maternal protein restriction induces hepatic metabolic adaptation characterized by enhanced oxidative stress, unbalanced expression in the antioxidant enzymes SOD1, SOD2 and CAT, and activation of inflammatory pathways but does not impact circulating markers of lipid metabolism and liver function.


Asunto(s)
Ácidos Grasos , Deficiencia de Proteína , Embarazo , Femenino , Ratas , Animales , Ácidos Grasos/metabolismo , Ratas Wistar , Antioxidantes/metabolismo , PPAR gamma/metabolismo , Hígado/metabolismo , Estrés Oxidativo , Dieta con Restricción de Proteínas/efectos adversos , Deficiencia de Proteína/metabolismo
9.
Am J Physiol Regul Integr Comp Physiol ; 302(6): R785-93, 2012 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-22204959

RESUMEN

Sympathetic overactivity and altered respiratory control are commonly observed after chronic intermittent hypoxia (CIH) exposure. However, the central mechanisms underlying such neurovegetative dysfunctions remain unclear. Herein, we hypothesized that CIH (6% O(2) every 9 min, 8 h/day, 10 days) in juvenile rats alters glutamatergic transmission in the commissural nucleus tractus solitarius (cNTS), a pivotal site for integration of peripheral chemoreceptor inputs. Using an in situ working heart-brain stem preparation, we found that l-glutamate microinjections (1, 3, and 10 mM) into the cNTS of control rats (n = 8) evoked increases in thoracic sympathetic nerve (tSN) and central vagus nerve (cVN) activities combined with inhibition of phrenic nerve (PN) activity. Besides, the ionotropic glutamatergic receptor antagonism with kynurenic acid (KYN; 250 mM) in the cNTS of control group (n = 7) increased PN burst duration and frequency. In the CIH group (n = 10), the magnitude of l-glutamate-induced cVN excitation was smaller, and the PN inhibitory response was blunted (P < 0.05). In addition, KYN microinjections into the cNTS of CIH rats (n = 9) did not alter PN burst duration and produced smaller increases in its frequency compared with controls. Moreover, KYN microinjections into the cNTS attenuated the sympathoexcitatory response to peripheral chemoreflex activation in control but not in CIH rats (P < 0.05). These functional CIH-induced alterations were accompanied by a significant 10% increase of N-methyl-D-aspartate receptor 1 (NMDAR1) and glutamate receptor 2/3 (GluR2/3) receptor subunit density in the cNTS (n = 3-8, P < 0.05), evaluated by Western blot analysis. These data indicate that glutamatergic transmission is altered in the cNTS of CIH rats and may contribute to the sympathetic and respiratory changes observed in this experimental model.


Asunto(s)
Hipoxia/fisiopatología , Receptores de Glutamato/fisiología , Sistema Respiratorio/fisiopatología , Núcleo Solitario/fisiopatología , Sistema Nervioso Simpático/fisiopatología , Animales , Antagonistas de Aminoácidos Excitadores/farmacología , Ácido Glutámico/administración & dosificación , Ácido Glutámico/farmacología , Ácido Quinurénico/administración & dosificación , Ácido Quinurénico/farmacología , Masculino , Microinyecciones , Modelos Animales , Ratas , Ratas Wistar , Receptores de Glutamato/efectos de los fármacos , Receptores de N-Metil-D-Aspartato/efectos de los fármacos , Receptores de N-Metil-D-Aspartato/fisiología
10.
Molecules ; 17(1): 809-19, 2012 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-22249410

RESUMEN

In this study, the antinociceptive properties of 3,4-dihydro-2,6-diaryl-4-oxo-pyrimidine-5-carbonitrile derivatives 5a-i at doses of 25 and 50 mg/kg were evaluated in mice, using the abdominal constriction test. Molecular modeling studies were also performed using density functional theory calculations. These data provided information about the electrostatic and ionization potentials and were used to compare the antinociceptive activity of the title compounds. The most active compounds were 3,4-dihydro-2-(4-chlorophenyl)-6-(4-methoxyphenyl)-4-oxo-pyrimidine-5-carbonitrile (5b) and 3,4-dihydro-2,6-diphenyl-4-oxo-pyrimidine-5-carbonitrile (5i), which inhibited the number of abdominal constrictions, at 50 mg/kg dose, in 88.6% and 88% of the sample, respectively. A preliminary SAR study demonstrated that halogen replacement in the phenyl rings of the compounds under study reduces the antinociceptive activity. DFT calculations showed that there is a high correlation between the ionization potentials and the analgesic properties of the compounds. It was found that compounds with a positive ionization potential (compounds 5b and 5i) were found to be the best analgesic drugs in this series.


Asunto(s)
Analgésicos/farmacología , Simulación por Computador , Nitrilos/farmacología , Pirimidinas/farmacología , Ácido Acético , Analgésicos/uso terapéutico , Animales , Evaluación Preclínica de Medicamentos , Masculino , Ratones , Modelos Moleculares , Nitrilos/uso terapéutico , Dolor/inducido químicamente , Dolor/tratamiento farmacológico , Pirimidinas/uso terapéutico
11.
J Sports Med Phys Fitness ; 61(9): 1281-1289, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34610730

RESUMEN

BACKGROUND: Physical activity plays an important role on children with obesity. This study evaluated the effects of plyometric training on the anthropometry, body composition, and the blood pressure (BP) and heart rate (HR) of boys with obesity. METHODS: Boys aged 7 to 9 years old were divided in: non-trained (N.=12) and trained (N.=29). The plyometric training program consisted of jumps on nonconsecutive days for twelve weeks. Anthropometry and body composition, BP and HR were evaluated. BP, HR and rate-pressure product were recorded at rest and 2 minutes after the section. Two-way repeated factors ANOVA was used. RESULTS: Trained group had a reduction in skinfolds and an increase in free fat mass (within and between-groups) and a large effect size for most anthropometric and body composition variables. Late systolic response was reduced from 122±1.1 (immediately post-exercise at the first week) to 112±1.0 at the end of plyometric training period. Diastolic reduction was seen two minutes after each session of exercise (from 68±1.1 to 62±1.2). HR was reduced in response to plyometric training (108 bpm to 97 bpm). CONCLUSIONS: Our findings strengthen previous studies that suggest that intense exercise has significant adaptive effects on BP and HR.


Asunto(s)
Ejercicio Pliométrico , Hipotensión Posejercicio , Composición Corporal , Niño , Humanos , Masculino , Obesidad , Sobrepeso
12.
J Neurophysiol ; 103(4): 2095-106, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20164386

RESUMEN

For a better understanding of the processing at the nucleus tractus solitarius (NTS) level of the autonomic and respiratory responses to peripheral chemoreceptor activation, herein we evaluated the role of glutamatergic neurotransmission in the intermediate (iNTS) and caudal NTS (cNTS) on baseline respiratory parameters and on chemoreflex-evoked responses using the in situ working heart-brain stem preparation (WHBP). The activities of phrenic (PND), cervical vagus (cVNA), and thoracic sympathetic (tSNA) nerves were recorded before and after bilateral microinjections of kynurenic acid (Kyn, 5 nmol/20 nl) into iNTS, cNTS, or both simultaneously. In WHBP, baseline sympathetic discharge markedly correlated with phrenic bursts (inspiration). However, most of sympathoexcitation elicited by chemoreflex activation occurred during expiration. Kyn microinjected into iNTS or into cNTS decreased the postinspiratory component of cVNA and increased the duration and frequency of PND. Kyn into iNTS produced no changes in sympathoexcitatory and tachypneic responses to peripheral chemoreflex activation, whereas into cNTS, a reduction of the sympathoexcitation, but not of the tachypnea, was observed. The pattern of phrenic and sympathetic coupling during the chemoreflex activation was an inspiratory-related rather than an expiratory-related sympathoexcitation. Kyn simultaneously into iNTS and cNTS produced a greater decrease in postinspiratory component of cVNA and increase in frequency and duration of PND and abolished the respiratory and autonomic responses to chemoreflex activation. The data show that glutamatergic neurotransmission in the iNTS and cNTS plays a tonic role on the baseline respiratory rhythm, contributes to the postinspiratory activity, and is essential to expiratory-related sympathoexcitation observed during chemoreflex activation.


Asunto(s)
Células Quimiorreceptoras/fisiología , Ácido Glutámico/efectos de los fármacos , Inhalación/fisiología , Ácido Quinurénico/farmacología , Nervio Frénico/fisiología , Núcleo Solitario/fisiología , Sistema Nervioso Simpático/fisiología , Animales , Células Quimiorreceptoras/efectos de los fármacos , Antagonistas de Aminoácidos Excitadores/administración & dosificación , Antagonistas de Aminoácidos Excitadores/farmacología , Espiración/efectos de los fármacos , Espiración/fisiología , Inhalación/efectos de los fármacos , Ácido Quinurénico/administración & dosificación , Masculino , Microinyecciones , Modelos Animales , Nervio Frénico/efectos de los fármacos , Ratas , Ratas Wistar , Núcleo Solitario/efectos de los fármacos , Sistema Nervioso Simpático/efectos de los fármacos , Transmisión Sináptica/efectos de los fármacos , Transmisión Sináptica/fisiología
13.
Eur J Nutr ; 48(7): 437-45, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19434436

RESUMEN

BACKGROUND: Epidemiological studies in the northeastern region of Brazil show an association between hypertension and malnutrition, especially in areas where protein-deficient diets are combined with high salt intake. AIMS OF STUDY: We studied the consequences of a widely consumed deficient diet (basic regional diet, BRD), combined with high NaCl, on growth, renal Na+ and water handling and activities of ATP-dependent Na+ transporters in kidney proximal tubules. METHODS: Young rats were fed after weaning with a low-protein and high-salt diet, which mimics that used in a vast region of Brazil. Body mass was evaluated from weaning up to the 19th week of age. Glomerular filtration rate, proximal Na+ reabsorption, distal Na+ delivery, urinary excretion of Na+ and water, and urine concentration capacity were evaluated from serum and urine concentrations of creatinine, Na+ and Li+, and by measurement of urinary volume and density. The (Na+ + K+)ATPase and the ouabain-insensitive Na+-ATPase were studied in vitro by measuring ATP hydrolysis. Expression of (Na+ + K+)ATPase was evaluated by immunodetection with the use of a specific antibody anti alpha1-catalytic subunit isoform. RESULTS: Undernourished rats reached early adulthood (14 weeks) with body and renal masses that were 2.3 times lower than controls. These rats became hypertensive (mean arterial pressure 18.7 +/- 0.6 kPa vs 15.5 +/- 0.9 kPa in control group) and showed augmented fractional proximal Na+ reabsorption (61.0 +/- 0.3% vs 81.8 +/- 2.2%) with a concomitant decrease in distal Na+ delivery (9.5 +/- 0.5 micromol/min vs 14.0 +/- 0.2 micromol/min per 100 g body weight). Urinary Na+ excretion was higher in BRD rats, (juvenile and adult) being however twice the increase in Na+ intake. The ATP-dependent Na+ transporters were affected in opposite ways. The (Na+ + K+)ATPase activity from undernourished rats fell by 30%, in parallel with a 20% decrease in its immunodetection, whereas the ouabain-insensitive Na+-ATPase, which is responsible for the fine-tune control of Na+ reabsorption, increased threefold. CONCLUSIONS: We conclude that early alterations in proximal tubule Na+ pumps, together with an abnormally augmented urinary Na+ excretion, might be the link between undernutrition and late renal dysfunction.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Envejecimiento , Proteínas de Transporte de Catión/metabolismo , Hipertensión/etiología , Riñón/enzimología , Desnutrición/metabolismo , Cloruro de Sodio Dietético/administración & dosificación , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Animales , Peso Corporal , Dieta con Restricción de Proteínas/efectos adversos , Pruebas de Función Renal , Masculino , Desnutrición/complicaciones , Tamaño de los Órganos , Ratas , Ratas Wistar , Sodio/orina , Cloruro de Sodio Dietético/efectos adversos
14.
Phytother Res ; 23(10): 1392-8, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19288530

RESUMEN

The present study was conducted to evaluate the effects of the administration of a hydroalcohol extract of Calendula officinalis L. flowers (HAE) on the reproductive function of Wistar rats. Four groups of adult male rats were treated orally with HAE at doses of 0, 0.25, 0.5 and 1.0 g/kg for 60 consecutive days. From day 53 to 60 of treatment, rats were mated with untreated and fertile female rats. Reproductive parameters including testicular morphology, reproductive organ weights, fertility index and offspring viability were evaluated. In another protocol, groups of pregnant rats were treated orally with the same doses of HAE from days 1 to 6 (preimplantation period), 7 to 14 (organogenic period) or 15 to 19 (fetal period) of pregnancy. On day 20 of pregnancy, rats were killed for evaluation of maternal and fetal parameters. The results showed that the treatment with HAE did not affect male reproductive parameters. Besides, it was non-toxic in the preimplantation and organogenic periods of pregnancy. However, the HAE induced a decrease of the maternal weight gain when administered during the fetal period. In conclusion, the HAE did not affect male fertility nor had toxic effects in early and middle periods of pregnancy. However, the HAE caused maternal toxicity when administered during the fetal period of pregnancy.


Asunto(s)
Calendula/toxicidad , Extractos Vegetales/toxicidad , Preñez/efectos de los fármacos , Reproducción/efectos de los fármacos , Aumento de Peso/efectos de los fármacos , Animales , Esquema de Medicación , Femenino , Fertilidad/efectos de los fármacos , Flores , Masculino , Tamaño de los Órganos/efectos de los fármacos , Embarazo , Ratas , Ratas Wistar , Testículo/efectos de los fármacos
15.
Sci Rep ; 9(1): 14406, 2019 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-31594995

RESUMEN

Maternal physical activity attenuates cardiorespiratory dysfunctions and transcriptional alterations presented by the carotid body (CB) of rats. Rats performed physical activity and were classified as inactive/active. During gestation and lactation, mothers received either normoprotein (NP-17% protein) or low-protein diet (LP-8% protein). In offspring, biochemical serum levels, respiratory parameters, cardiovascular parameters and the mRNA expression of hypoxia-inducible factor 1-alpha (HIF-1α), tyrosine hydroxylase (TH) and purinergic receptors were evaluate. LP-inactive pups presented lower RF from 1st to 14th days old, and higher RF at 30 days than did NP-inactive and NP-active pups. LP-inactive pups presented with reduced serum protein, albumin, cholesterol and triglycerides levels and an increased fasting glucose level compared to those of NP-inactive and NP-active groups. LP and LP-inactive animals showed an increase in the cardiac variability at the Low-Frequency bands, suggesting a major influence of sympathetic nervous activity. In mRNA analyses, LP-inactive animals showed increased HIF-1α expression and similar expression of TH and purinergic receptors in the CB compared to those of NP groups. All these changes observed in LP-inactive pups were reversed in the pups of active mothers (LP-active). Maternal physical activity is able to attenuate the metabolic, cardiorespiratory and HIF-1α transcription changes induced by protein malnutrition.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Desnutrición/prevención & control , Fenómenos Fisiologicos Nutricionales Maternos/genética , Efectos Tardíos de la Exposición Prenatal , Animales , Capacidad Cardiovascular/fisiología , Sistema Cardiovascular/fisiopatología , Cuerpo Carotídeo/fisiopatología , Dieta con Restricción de Proteínas , Femenino , Regulación de la Expresión Génica/genética , Humanos , Lactancia/fisiología , Desnutrición/genética , Desnutrición/fisiopatología , Condicionamiento Físico Animal , Embarazo , Ratas , Ratas Wistar , Sistema Nervioso Simpático/fisiopatología
16.
Cells ; 8(4)2019 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-30974751

RESUMEN

The nutritional transition that the western population has undergone is increasingly associated with chronic metabolic diseases. In this work, we evaluated a diet rich in saturated fatty acids (hyperlipidic, HL) after weaning of the offspring rats submitted to maternal protein restriction on the hepatic mitochondrial bioenergetics. Wistar rats were mated and during gestation and lactation, mothers received control diets (NP, normal protein content 17%) or low protein (LP, 8% protein). After weaning, rats received either NL (normolipidic) or HL (+59% SFA) diets up to 90 days of life. It was verified that all respiratory states of hepatic mitochondria showed a reduction in the LP group submitted to the post-weaning HL diet. This group also presented greater mitochondrial swelling compared to controls, potentiated after Ca2+ addition and prevented in the presence of EGTA (calcium chelator) and cyclosporin A (mitochondrial permeability transition pore inhibitor). There was also an increase in liver protein oxidation and lipid peroxidation and reduction in catalase and glutathione peroxidase activities in the LP group fed HL diet after weaning. Our data suggest that adult rats subjected to maternal protein restriction were more susceptible to hepatic mitochondrial damage caused by a diet rich in saturated fatty acids post-weaning.


Asunto(s)
Metabolismo Energético , Hígado/metabolismo , Mitocondrias/metabolismo , Animales , Dieta Alta en Grasa , Dieta con Restricción de Proteínas , Femenino , Masculino , Oxidación-Reducción , Embarazo , Efectos Tardíos de la Exposición Prenatal , Fenómenos Fisiologicos de la Nutrición Prenatal , Ratas , Ratas Wistar
17.
Front Physiol ; 7: 504, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27899895

RESUMEN

Developmental origins of cardiometabolic diseases have been related to maternal nutritional conditions. In this context, the rising incidence of arterial hypertension, diabetes type II, and dyslipidemia has been attributed to genetic programming. Besides, environmental conditions during perinatal development such as maternal undernutrition or overnutrition can program changes in the integration among physiological systems leading to cardiometabolic diseases. This phenomenon can be understood in the context of the phenotypic plasticity and refers to the adjustment of a phenotype in response to environmental input without genetic change, following a novel, or unusual input during development. Experimental studies indicate that fetal exposure to an adverse maternal environment may alter the morphology and physiology that contribute to the development of cardiometabolic diseases. It has been shown that both maternal protein restriction and overnutrition alter the central and peripheral control of arterial pressure and metabolism. This review will address the new concepts on the maternal diet induced-cardiometabolic diseases that include the potential role of the perinatal malnutrition.

18.
Front Physiol ; 7: 448, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27766081

RESUMEN

Arterial hypertension (AH) is one of the most prevalent risk factors for cardiovascular diseases (CD) and is the main cause of deaths worldwide. Current research establish that dietary polyphenols may help to lower blood pressure (BP), thus contributing to the reduction of cardiovascular complications. In addition, the health benefits of probiotics on BP have also attracted increased attention, as probiotics administration modulates the microbiota, which, by interacting with ingested polyphenols, controls their bioavalability. The aim of the present mini-review is to summarize and clarify the effects of dietary polyphenols and probiotics administration on BP using combined evidence from clinical and experimental studies, as well as to discuss the current debate in the literature about the usefulness of this nutritional approach to manage BP. Clinical trials and experimental studies have demonstrated that consuming dietary polyphenols or probiotics in adequate amounts may improve BP, ranging from modest to greater effects. However, the mechanisms linking probiotic intake and reduced BP levels need to be further elucidated as a definitive consensus on the link between intake of polyphenols or probiotics and improvement of AH has not been reached yet.

19.
Front Physiol ; 6: 345, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26635631

RESUMEN

Systemic arterial hypertension (SAH) is an important risk factor for cardiovascular disease and affects worldwide population. Current environment including life style coupled with genetic programming have been attributed to the rising incidence of hypertension. Besides, environmental conditions during perinatal development such as maternal malnutrition can program changes in the integration among renal, neural, and endocrine system leading to hypertension. This phenomenon is termed phenotypic plasticity and refers to the adjustment of a phenotype in response to environmental stimuli without genetic change, following a novel or unusual input during development. Human and animal studies indicate that fetal exposure to an adverse maternal environment may alter the renal morphology and physiology that contribute to the development of hypertension. Recently, it has been shown that the maternal protein restriction alter the central control of SAH by a mechanism that include respiratory dysfunction and enhanced sympathetic-respiratory coupling at early life, which may contribute to adult hypertension. This review will address the new insights on the maternal diet induced-hypertension that include the potential role of the phenotypic plasticity, specifically the perinatal protein malnutrition, and sympathetic-respiratory overactivity.

20.
J Ethnopharmacol ; 136(2): 341-6, 2011 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-21571057

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Cassia occidentalis L. (syn. Senna occidentalis; Leguminosae) has been used as natural medicine in rainforests and tropical regions as laxative, analgesic, febrifuge, diuretic, hepatoprotective, vermifuge and colagogo. Herein, we performed a pre-clinical safety evaluation of hydroalcoholic extract of Cassia occidentalis stem and leaf in male and female Wistar rats. MATERIALS AND METHODS: In acute toxicity tests, four groups of rats (n=5/group/sex) were orally treated with doses of 0.625, 1.25, 2.5 and 5.0 g/kg and general behavior, adverse effects and mortality were recorded for up to 14 days. In subacute toxicity assays, animals received Cassia occidentalis by gavage at the doses of 0.10, 0.50 or 2.5 g/kg/day (n=10/group/sex) for 30 days and biochemical, hematological and morphological parameters were determined. RESULTS: Cassia occidentalis did not produce any hazardous symptoms or death in the acute toxicity test, showing a LD(50) higher than 5 g/kg. Subacute treatment with Cassia occidentalis failed to change body weight gain, food and water consumption and hematological and biochemical profiles. In addition, no changes in macroscopical and microscopical aspect of organs were observed in the animals. CONCLUSIONS: Our results showed that acute or subacute administration of Cassia occidentalis is not toxic in male and female Wistar rats, suggesting a safety use by humans.


Asunto(s)
Cassia/toxicidad , Extractos Vegetales/toxicidad , Animales , Conducta Animal/efectos de los fármacos , Biomarcadores/sangre , Peso Corporal/efectos de los fármacos , Femenino , Masculino , Hojas de la Planta , Tallos de la Planta , Ratas , Ratas Wistar
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