Valproate decreases transgenerationally blood pressure by affecting thyrotropin-releasing hormone promoter DNA methylation and gene expression in spontaneously hypertensive rat.

Central TRH, a neuropeptide, is involved in cardiovascular regulation. We demonstrated that the overexpression of diencephalic TRH (dTRH) in SHR rats can be prevented by antisense treatment, normalizing blood pressure (BP). Valproate (VPA) is an inhibitor of histone deacetylases (HDAC) which modulates gene expression through epigenetic modifications such as DNA methylation. AIMS: Study the role of HDAC inhibition in the regulation of dTRH gene expression and its effect on the pathogenesis of hypertension. MAIN METHODS: We treated 7-weeks-old male and female SHR and WKY rats with VPA for 10 weeks and evaluated BP, dTRH mRNA and methylation gene status. KEY FINDINGS: VPA attenuated the elevated BP and dTRH mRNA expression characteristic of SHR. Indeed, we found a significant 62% reduction in dTRH mRNA expression in the SHR + VPA group compared to control SHR. The decrease TRH mRNA expression induced by VPA was confirmed "in vitro" in a primary neuron culture using trichostatin A. With methylation specific PCR we demonstrated a significant increase in TRH promoter DNA methylation level in SHR + VPA group compared to control SHR. After 2 weeks of treatment interruption, rats were mated. Although they did not receive any treatment, the offspring born from VPA-treated SHR parents showed similar changes in BP, dTRH expression and methylation status, implying a transgenerational inheritance. Our findings suggest that dTRH modulation by epigenetics mechanism affects BP and could be inherited by the next generation in SHR rats.

Novel Leptin-Cardiac TRH pathway responsible for the cardiac alterations in the Hyperleptinemic obesity.

The association between hypertension and obesity-induced cardiac damage is usually accepted. However, no studies have been focused on cardiac alterations in obesity, independently of blood pressure increase. It is well known that Cardiac TRH induces Left Ventricular Hypertrophy (LVH) and fibrosis, and its inhibition prevents the development of hypertrophy. Also, it has been described that the adiponectin leptin induces TRH expression. Thus, we hypothesized that in obesity, the increase in TRH induced by hyperleptinemia is responsible for LVH, until now mostly attributed to pressure load. We studied obese Agouti mice suffering from hypertension with hyperleptinemia and found a significant LVH development with increased TRH gene expression. Consequently, we found higher fibrotic (collagens and TGF-ß) and hypertrophic markers (BNP and ß-MHC) expression vs lean black controls. As pressure could explain these results, we treated obese mice with diuretic (hydrochlorothiazide 20 mg/kg/day) since weaning. Diuretic treatment was successful as the diuretic group was normotensive in contrast to control obese mice. Nevertheless, both groups showed LVH development, higher cardiac precursor TRH gene and peptide expressions and elevated fibrotic and hypertrophic markers expression, pointing out that obesity-induced LVH is not due to hypertension. In addition, we performed Cardiac TRH inhibition by specific siRNA injection compared to control siRNA treatment and evaluated cardiac damage. As expected, expressions and protein increase in hypertrophic and fibrotic markers observed in the AG mouse with the native cTRH system were not seen in the AG mouse with the cTRH silencing. Indeed, the AG + TRH-siRNA group showed hypertrophic markers expression and fibrosis measurements similar to the lean BL mice. On the whole, these results point out that the novel Leptin-Cardiac TRH pathway is responsible for the cardiac alterations present in hyperleptinemic obesity, independent of blood pressure, and cTRH long-term silencing since early stages totally prevent LVH development and cardiac fibrosis.

Cardiac Thyrotropin-releasing Hormone Inhibition Improves Ventricular Function and Reduces Hypertrophy and Fibrosis After Myocardial Infarction in Rats.

BACKGROUND: Cardiac thyrotropin-releasing hormone (TRH) is a tripeptide with still unknown functions. We demonstrated that the left ventricle (LV) TRH system is hyperactivated in spontaneously hypertensive rats and its inhibition prevented cardiac hypertrophy and fibrosis. Therefore, we evaluated whether in vivo cardiac TRH inhibition could improve myocardial function and attenuate ventricular remodeling in a rat model of myocardial infarction (MI). METHODS AND RESULTS: In Wistar rats, MI was induced by a permanent left anterior descending coronary artery ligation. A coronary injection of a specific small interfering RNA against TRH was applied simultaneously. The control group received a scrambled small interfering RNA. Cardiac remodeling variables were evaluated one week later. In MI rats, TRH inhibition decreased LV end-diastolic (1.049 ± 0.102 mL vs 1.339 ± 0.102 mL, P < .05), and end-systolic volumes (0.282 ± 0.043 mL vs 0.515 ± 0.037 mL, P < .001), and increased LV ejection fraction (71.89 ± 2.80% vs 65.69 ± 2.85%, P < .05). Although both MI groups presented similar infarct size, small interfering RNA against TRH treatment attenuated the cardiac hypertrophy index and myocardial interstitial collagen deposition in the peri-infarct myocardium. These effects were accompanied by attenuation in the rise of transforming growth factor-ß, collagen I, and collagen III, as well as the fetal genes (atrial natriuretic peptide, B-type natriuretic peptide, and beta myosin heavy chain) expression in the peri-infarct region. In addition, the expression of Hif1α and vascular endothelial growth factor significantly increased compared with all groups. CONCLUSIONS: Cardiac TRH inhibition improves LV systolic function and attenuates ventricular remodeling after MI. These novel findings support the idea that TRH inhibition may serve as a new therapeutic strategy against the progression of heart failure.

Cardiovascular and body weight regulation changes in transgenic mice overexpressing thyrotropin-releasing hormone (TRH).

Thyrotropin-releasing hormone (TRH) plays several roles as a hormone/neuropeptide. Diencephalic TRH (dTRH) participates in the regulation of blood pressure in diverse animal models, independently of the thyroid status. The present study aimed to evaluate whether chronic overexpression of TRH in mice affects cardiovascular and metabolic variables. We developed a transgenic (TG) mouse model that overexpresses dTrh. Despite having higher food consumption and water intake, TG mice showed significantly lower body weight respect to controls. Also, TG mice presented higher blood pressure, heart rate, and locomotor activity independently of thyroid hormone levels. These results and the higher urine noradrenaline excretion observed in TG mice suggest a higher metabolic rate mediated by sympathetic overflow. Cardiovascular changes were impeded by siRNA inhibition of the diencephalic Trh overexpression. Also, the silencing of dTRH in the TG mice normalized urine noradrenaline excretion, supporting the view that the cardiovascular effects of TRH involve the sympathetic system. Overall, we show that congenital dTrh overexpression leads to an increase in blood pressure accompanied by changes in body weight and food consumption mediated by a higher sympathetic overflow. These results provide new evidence confirming the participation of TRH in cardiovascular and body weight regulation.

Short-term doxorubicin cardiotoxic effects: involvement of cardiac Thyrotropin Releasing Hormone system.

Doxorubicin is an antineoplastic in the anthracycline class widely used for the treatment of several solid tumors and blood cancers. Cardiotoxicity is the major dose-limiting adverse effect of the drug. Chronic and accumulated doxorubicin administration cause myocyte damage and myocardial fibrosis. Doxorubicin-associated cardiotoxicity can be also observed after a short-course drug treatment even without clinical evidence of cardiac disease. Nevertheless, acute underlying mechanisms involved in the initiation of drug-induced cardiotoxicity remain poorly explored despite their similarities with pathophysiological conditions where cardiac TRH (cTRH) plays a central role. We showed that cTRH mediates myocardial injury induced by hypertension, and angiotensin II. Further, cTRH overexpression induces cardiac apoptosis, hypertrophy and fibrosis. AIM: To demonstrate that cTRH could mediate acute doxorubicin cardiotoxicity. MAIN METHOD: A single injection of doxorubicin (10 mg kg/day i.p.) was used to evaluate acute cardiac damage in a short-term experimental model of doxorubicin-induced cardiotoxicity. While inhibiting cTRH by small interfering RNA (siRNA), we evaluated the progression of cardiotoxicity. KEY FINDINGS: We found a doxorubicin-induced TRH overexpression in the LV, which was associated with apoptosis, hypertrophy and fibrosis. siRNA-mediated cTRH suppression prevented the doxorubicin-associated cardiac histological lesions. SIGNIFICANCES: doxorubicin requires an active cardiac TRH system to promote heart injury.

Angiotensin II requires an intact cardiac thyrotropin-releasing hormone (TRH) system to induce cardiac hypertrophy in mouse.

Cardiac tyhrotropin-releasing hormone (TRH) is overexpressed in the hypertrophied left ventricle (LV) of spontaneously hypertensive rats (SHR) and its inhibition prevents both hypertrophy and fibrosis. In a normal heart, the TRH increase induces fibrosis and hypertrophy opening the question of whether TRH could be a common mediator of left ventricular hypertrophy (LVH). We used angiotensin II (AngII) as an inductor of LVH to evaluate if the blockade of LV-TRH prevents hypertrophy and fibrosis in mice. We challenged C57BL/6 adult male mice with an infusion of AngII (osmotic pumps; 2 mg/kg.day) to induce LVH. Groups of mice were injected with an intracardiac siRNA-TRH or scrambled siRNA (siRNA-Con). Body weight, water intake and systolic arterial blood pressure (SABP) were measured daily. AngII significantly increased water intake and SABP (p < .05). Cardiac hypertrophy (heart weight/body weight) was evident in the group with the normal cardiac TRH system. In fact, it was found an AngII-induced increase of TRH precursor mRNA (p < .05) in conjunction with elevated TRH levels measured by immunohistochemistry and western blot. These changes were not observed in the AngII + siRNA-TRH group. Furthermore, AngII increased significantly (p < .05) BNP (hypertrophic marker), collagens I and III and TGF-ß (fibrosis markers) expression in the group with the native cardiac TRH system. These increases were attenuated in the groups with the TRH system blocked despite the high blood pressure. Similar and stronger results were observed "in vitro" with NIH3T3 and H9C2 cell culture models, where, when the TRH system is blocked, AngII stimulus was not able to induce the markers of its fibrotic and hypertrophic effects, so we believe that these effects are independent of any other physiological modifications. Our results point out that cardiac TRH is required for AngII-induced hypertrophic and fibrotic effects.

Software para la conectividad de la consuta provincial del neurodesarrollo infantil y la discapacidad en Santiago de Cuba / Software for connectivity of the medical consultation for infant neuro-development and handicap in Santiago de Cuba

El presente trabajo aborda los primeros pasos hacia la conexión informática de las entidades que conforman la Consulta Provincial del Neurodesarrollo Infantil y la Discapacidad (CPNDI) en Santiago de Cuba. Se propone un sistema basado en tecnología Web para su uso en infraestructuras de comunicación limitadas como ocurre en zonas rurales, desarrollado en colaboración con la Universidad de Ciencias Aplicadas de Dus-seldorf y la Univ. Benemérita de Puebla, México. El sistema se basa en el acoplamiento de un sistema de gestión de pacientes con acceso a equipos médicos ambulatorios con un sistema de asistencia especializada orientado al tratamiento de pacientes vía un navegador de internet. La combinación efectiva de aplicaciones web remotas y locales facilita una integración efectiva del equipamiento médico ambulatorio requerido en el sitio remoto donde se encuentra el paciente con el sistema de asistencia especializada donde se encuentran los doctores y especialistas todo a través de tecnología web(AU)

In this paper are discussed, the first steps for a telemedicine network which connects the units and places within the Medical Consultation for Infant Neurodevelopment and Handicap (CPNDI) in Santiago de Cuba. A web-based system for use to connect sites within the CPNDI structure and to access rural areas with limited communication infrastructures is finally proposed. The system consists of a patient management system and a medical device system that are available to the doctor and the patient-side assistant during treatment via an Internet browser. The combination of local and remote web applications enables a seamless integration of the medical devices required at the patient's location into the doctor's remote station based on browser technology(AU)

Software para la conectividad de la consuta provincial del neurodesarrollo infantil y la discapacidad en Santiago de Cuba / Software for connectivity of the medical consultation for infant neuro-development and handicap in Santiago de Cuba

El presente trabajo aborda los primeros pasos hacia la conexión informática de las entidades que conforman la Consulta Provincial del Neurodesarrollo Infantil y la Discapacidad (CPNDI) en Santiago de Cuba. Se propone un sistema basado en tecnología Web para su uso en infraestructuras de comunicación limitadas como ocurre en zonas rurales, desarrollado en colaboración con la Universidad de Ciencias Aplicadas de Dus-seldorf y la Univ. Benemérita de Puebla, México. El sistema se basa en el acoplamiento de un sistema de gestión de pacientes con acceso a equipos médicos ambulatorios con un sistema de asistencia especializada orientado al tratamiento de pacientes vía un navegador de internet. La combinación efectiva de aplicaciones web remotas y locales facilita una integración efectiva del equipamiento médico ambulatorio requerido en el sitio remoto donde se encuentra el paciente con el sistema de asistencia especializada donde se encuentran los doctores y especialistas todo a través de tecnología web(AU)

In this paper are discussed, the first steps for a telemedicine network which connects the units and places within the Medical Consultation for Infant Neurodevelopment and Handicap (CPNDI) in Santiago de Cuba. A web-based system for use to connect sites within the CPNDI structure and to access rural areas with limited communication infrastructures is finally proposed. The system consists of a patient management system and a medical device system that are available to the doctor and the patient-side assistant during treatment via an Internet browser. The combination of local and remote web applications enables a seamless integration of the medical devices required at the patient's location into the doctor's remote station based on browser technology(AU)

Thyrotropin-releasing hormone overexpression induces structural changes of the left ventricle in the normal rat heart.

Thyrotropin-releasing hormone (TRH) hyperactivity has been observed in the left ventricle of spontaneously hypertensive rats. Its long-term inhibition suppresses the development of hypertrophy, specifically preventing fibrosis. The presence of diverse systemic abnormalities in spontaneously hypertensive rat hearts has raised the question of whether specific TRH overexpression might be capable of inducing structural changes in favor of the hypertrophic phenotype in normal rat hearts. We produced TRH overexpression in normal rats by injecting into their left ventricular wall a plasmid driving expression of the preproTRH gene (PCMV-TRH). TRH content and expression of preproTRH, collagen type III, brain natriuretic peptide, ß-myosin heavy chain, Bax-to-Bcl-2 ratio, and caspase-3 were measured. The overexpression maneuver was a success, as we found a significant increase in both tripeptide and preproTRH mRNA levels in the PCMV-TRH group compared with the control group. Immunohistochemical staining against TRH showed markedly positive brown signals only in the PCMV-TRH group. TRH overexpression induced a significant increase in fibrosis, evident in the increase of collagen type III expression accompanied by a significant increase in extracellular matrix expansion. We found a significant increase in brain natriuretic peptide and ß-myosin heavy chain expression (recognized markers of hypertrophy). Moreover, TRH overexpression induced a slight but significant increase in myocyte diameter, indicating the onset of cell hypertrophy. We confirmed the data "in vitro" using primary cardiac cell cultures (fibroblasts and myocytes). In conclusion, these results show that a specific TRH increase in the left ventricle induced structural changes in the normal heart, thus making the cardiac TRH system a promising therapeutic target.

Vitamina D en pacientes con síndrome metabólico de la ciudad de valencia, venezuela / Vitamin D in patients with metabolic syndrome from valencia City, venezuela abstract

Entre los efectos no clásicos de la Vitamina D destaca su asociación con el sistema cardiovascular y su disminución, se relaciona con factores de riesgo que definen al Síndrome Metabólico (SM). Es por ello que el objetivo de este estudio fue evaluar los niveles de Vitamina D en pacientes con SM y relacionarlos con sus componentes. Fueron estudiados 31 individuos con SM que acudieron a consultas de medicina interna en el Instituto Venezolano de Seguro Social “Dr. Luis Guada Lacau” y el Ambulatorio Urbano “Dr. Miguel Franco” del Municipio Naguanagua, Edo. Carabobo durante el primer trimestre del año 2011. A los mismos les fueron medidos los niveles de 25-(OH)-Vitamina D, circunferencia abdominal, presión arterial, perfil lipídico y glicemia, así como los índices aterogénicos y la relación TG/HDL-c. 54% de los participantes presentó niveles insuficientes de Vitamina D, asociándose estadísticamente a LDL-c elevado (chi-cuadrado=3,77; p-valor=0,052), mostrando además una correlación media y positiva con los valores de esta lipoproteína (r=0.3813; p-valor=0.0350) y con la relación LDL-c/HDL-c (r=0.3820; p-valor=0,0340). No se encontraron diferencias estadísticamente significativas entre los parámetros evaluados al dividir la muestra según la presencia o no de insuficiencia de vitamina D (prueba t de Student y Prueba de Wilcoxon-U-Mann Whitney). Los resultados obtenidos confirman la hipótesis de que la hipovitaminosis D puede ser considerada como un factor de riesgo para desarrollar SM, sugiriendo la realización de futuras investigaciones que contribuyan a profundizar la participación de la insuficiencia de esta vitamina y su posible interacción con otros factores no clásicos de riesgo cardiovascular(AU)

Among the nonclassical effects of vitamin D highlights its association with cardiovascular system, strongly associating your decline to risk factors that define the metabolic syndrome (MS). That is why the aim of this study was to assess vitamin D levels in patients with MS and link components. Was study 31 subjects with MS attending internal medicine clinics at the Venezuelan Institute of Social Security, “Dr. Luis Guada Lacau” and the Ambulatory Urban “Dr. Miguel Franco” of Naguanagua, Edo. Carabobo during the first quarter of 2011. At the same they were measured the levels of 25 - (OH)-vitamin D, waist circumference, blood pressure, lipid profile and glucose, and the atherogenic index and the ratio TG/HDL-c. 54% of participants had insufficient levels of Vitamin D, associated statistically elevated LDL-c (chi-square=3.77, p-value=0.052), also showing average and positive correlation with the values of this lipoprotein (r=0.3813, p-value=0.0350) and LDL-C/HDL-C relationship (r=0.3820, p-value=0.0340). No statistically significant differences were found between the parameters evaluated by dividing the sample according to the presence or absence of vitamin D insufficiency (Student’s t and Wilcoxon- U Mann-Whitney test). The results confirm the hypothesis that vitamin D deficiency may be considered a risk factor for developing MS, suggesting future conducting research that contributes to deepen the involvement of the failure of this vitamin and its possible interaction with other factors nonclassical cardiovascular risk(AU)

Cardiac thyrotropin-releasing hormone mediates left ventricular hypertrophy in spontaneously hypertensive rats.

Local thyrotropin-releasing hormone (TRH) may be involved in cardiac pathophysiology, but its role in left ventricular hypertrophy (LVH) is still unknown. We studied whether local TRH is involved in LVH of spontaneously hypertensive rats (SHR) by investigating TRH expression and its long-term inhibition by interference RNA (TRH-iRNA) during LVH development at 2 stages (prehypertrophy and hypertrophy). SHR and their control rats (WKY) were compared. Cardiac hypertrophy was expressed as heart/total body weight (HW/BW) ratio. TRH content (radioimmuno assay), preproTRH, TRH receptor type I, brain natriuretic peptide (BNP), and collagen mRNA expressions (real-time polymerase chain reaction) were measured. For long-term inhibition of TRH, TRH-iRNA was injected into the left ventricle (LV) wall for 8 weeks. Hearts were processed for morphometric studies and immunohistochemical analysis using antibodies against α-smooth muscle actin and collagen type III. LV preproTRH-mRNA abundance was similar in both strains at 7 weeks of age. At the hypertrophic stage (18 weeks old), however, there was a 15-fold increase in SHR versus WKY, consistent with a significant increase in tripeptide levels and the expression of its receptor. Specific LV-TRH inhibition at the prehypertensive stage with TRH-iRNA, which decreased >50% preproTRH expression and tripeptide levels, prevented LVH development as shown by the normal HW/BW ratio observed in TRH-iRNA-treated SHR. In addition, TRH-iRNA impeded the increase in BNP and type III collagen expressions and prevented the increase in cardiomyocyte diameter evident in mismatch iRNA-treated adult SHR. These results show for the first time that the cardiac TRH system is involved in the development of LVH in SHR.