Endotelina-1, proteína C reactiva ultrasensible y actividad antioxidante en pacientes con hipotiroidismo subclínico y en eutiroideos con autoinmunidad tiroidea. Efectos del tratamiento con levotiroxina / Endothelin-1, high sensitivity C reactive protein and antioxidant activity in subclinical hypothyroid patients. Effects of levothyroxine treatment

RESUMEN La Endotelina-1 (ET1) y Proteína C Reactiva ultrasensible (PCRus) como marcadores de disfunción endotelial (DE) e inflamación vascular en hipotiroidismo subclínico (HS) han mostrado resultados controvertidos. El rol del estrés oxidativo y defensa antioxidante (TRAP) es motivo de discusión. Objetivos Establecer si el HS y la autoinmunidad tiroidea (AIT), excluyendo otros factores de riesgo cardiovascular, pueden causar DE e inflamación vascular, evaluadas a través de ET1 y PCRus, respectivamente. Establecer si TRAP juega algún rol. Evaluar cambios en ET1 y PCRus luego del tratamiento con levotiroxina (LT4). Material y métodos Se evaluaron prospectivamente 70 pacientes divididos en 3 grupos: HS: 41 pacientes (T4 normal,TSH >4,2 y <10 mUI/L), AIT: 10 pacientes eutiroideos (TSH <4,2 mUI/L) con aTPO y/o aTg (+) y Control: 19 pacientes eutiroideos sin AIT. Se excluyeron otros factores de riesgo cardiovascular. Se midió basalmente ET1, PCRus y TRAP plasmáticos, y en HS bajo LT4 (n = 24): ET1 y PCRus. Resultados No hubo diferencias significativas en edad, IMC, perfil lipídico y TRAP. ET1 y PCRus fueron significativamente mayores en pacientes con HS (media ± DS 1,77 ± 0,85 pg/ml y 1,5 ± 0,6 mg/l vs. controles (0,8 ± 0,3 pg/ml y 0,5 ± 0,2 mg/l) p <0,0001 y <0,008 respectivamente. Del mismo modo en AIT (1,4 ± 0.4 pg/ml y 2,3 ± 1,3 mg/l) vs controles p <0,0001 y <0,034, respectivamente. La TSH fue mayor en el grupo AIT vs. Control 2,57 ± 0,88 vs. 1,64 ± 0,5 mUI/L; p = 0,002. En HS bajo LT4 (8,7 ± 3,8 meses) se observó descenso de ET1 (p <0,001). ET1 correlacionó con TSH (r = 0,5 p <0,0001). El punto de corte de ET1 mediante curva ROC fue 1,32 pg/ml (Sensibilidad 81,6%-Especificidad 75%). Conclusiones ET1 y PCRus resultaron marcadores útiles para evaluar DE e inflamación vascular asociadas a HS. La defensa antioxidante no ejercería un rol en estos mecanismos. El tratamiento con LT4 produjo una significativa caída de ET1, pudiendo necesitarse un período más largo de eutiroidismo para normalizarla. En AIT, niveles de TSH >2,5 mUI/L podrían sugerir un mínimo grado de hipotiroidismo justificando la elevación en ET1 y PCR, sin descartar el rol de la AIT "per se".

ABSTRACT The measurement of endothelin-1 (ET1) and high sensitivity C-reactive protein (hsCRP) as markers of endothelial dysfunction (ED) and vascular inflammation in subclinical hypothyroidism (SH) has shown controversial results. The role of oxidative stress and antioxidant defense (TRAP) is a matter of discussion. Objectives To establish if SH and thyroid autoimmunity (TAI), excluding other cardiovascular risk factors, may cause ED and vascular inflammation, evaluated through the measurement of ET1 and hsCRP respectively. To determine if TRAP could have some role. Additionally, changes in these parameters after treatment with levothyroxine (LT4) will be evaluated. Material and methods: 70 patients were prospectively evaluated. They were classified into: SH Group: 41 patients (normal T4, TSH> 4.2 and <10 mIU/L), TAI Group: 10 euthyroid patients (TSH <4.2 mUI/L) with positive aTPO and/or aTg and Control Group: 19 euthyroid patients without TAI. Other cardiovascular risk factors were excluded in patients and controls. Plasma ET1, hsCRP and TRAP were measured basally, and ET1 and hsCRP under LT4 therapy in the HS Group. Results There were no significant differences between the 3 groups in age, BMI, lipids and TRAP. ET1 and hsCRP were significantly higher in patients with SH (mean ± SD 1.77 ± 0.85 pg/ml and 1.5 ± 0.6 mg/l) vs. controls (0.8 ± 0.3 pg/ml y 0.5 ± 0.2 mg/l) p <0.0001 y <0.008 respectively. Similarly, in TAI patients (1.4 ± 0.4 pg/ml y 2.3 ± 1.3 mg/l) vs controls, p <0.0001 and <0.034, respectively. TSH was higher in the TAI patients versus control group (2.5 ± 0.88 versus 1.64 ± 0.5 mIU/L, p = 0.002). Twenty-four patients with SH showed a significant decrease in ET1 (p <0.001) under treatment with LT4 (8.7 ± 3.8 months). ET1 had a highly significant correlation (p <0.0001) with TSH (r = 0.5). The cut-off level of ET1 established by ROC curve was 1.32 pg/ml (Sensitivity 81.6%-Specificity 75%). Conclusions ET1 and hsCRP were useful markers to evaluate ED and vascular inflammation associated with SH. There were no differences in TRAP levels between patients and controls, so it does not appear that oxidative stress would have played any role. Treatment with LT4 produced a significant drop in ET1. Probably, a longer period of euthyroidism might be necessary to normalize ET1 levels. In TAI Group, TSH levels >2.5 mUI/L could suggest a "minimal degree" of hypothyroidism justifying the elevation in ET1 and hs CRP. The role of the TAI "per se" couldn't be completely ruled out.

Expression profile of endothelin receptors (ETA and ETB) and microRNAs-155 and -199 in the corpus cavernosum of rats submitted to chronic alcoholism and diabetes mellitus

Recent evidence shows that chronic ethanol consumption increases endothelin (ET)-1 induced sustained contraction of trabecular smooth muscle cells of the corpora cavernosa in corpus cavernosum of rats by a mechanism that involves increased expression of ETA and ETB receptors. Our goal was to evaluate the effects of alcohol and diabetes and their relationship to miRNA-155, miRNA-199 and endothelin receptors in the corpus cavernosum and blood of rats submitted to the experimental model of diabetes mellitus and chronic alcoholism. Forty-eight male Wistar rats were divided into four groups: control (C), alcoholic (A), diabetic (D), and alcoholic-diabetic (AD). Samples of the corpus cavernosum were prepared to study the protein expression of endothelin receptors by immunohistochemistry and expression of miRNAs-155 and -199 in serum and the cavernous tissue. Immunostaining for endothelin receptors was markedly higher in the A, D, and AD groups than in the C group. Moreover, a significant hypoexpression of the miRNA-199 in the corpus cavernosum tissue from the AD group was observed, compared to the C group. When analyzing the microRNA profile in blood, a significant hypoexpression of miRNA-155 in the AD group was observed compared to the C group. The miRNA-199 analysis demonstrated significant hypoexpression in D and AD groups compared to the C group. Our findings in corpus cavernosum showed downregulated miRNA-155 and miRNA-199 levels associated with upregulated protein expression and unaltered mRNA expression of ET receptors suggesting decreased ET receptor turnover, which can contribute to erectile dysfunction in diabetic rats exposed to high alcohol levels.

Analysis of immunostaining and western blotting of endothelin 1 and its receptors in mitral stenosis / Análise da expressão imunohistoquímica e de western blotting da endotelina 1 e seus receptores na estenose mitral

Abstract Introduction: Rheumatic Fever represents a serious public health problem in developing countries, with thousands of new cases each year. It is an autoimmune disease, which occurs in response to infection by streptococcus A. Objective: The aim of this study was to evaluate the immunolabeling and protein expression for endothelin-1 and 3 (ET-1, ET-3) and its receptors (ETA, ETB) in rheumatic mitral valves. Methods: Immunohistochemistry was used to identify ET-1/ET-3 and ETA/ETB receptors in rheumatic and control mitral valves. Quantitative analysis of immunostaining for ET-1/ET-3 and ETA/ETB receptors was performed. In addition, western blot analysis was carried out to assess protein levels in tissue samples. Results: ET-1 and ETA receptor immunostaining predominated in stenotic valves, mainly associated with fibrotic regions, inflammatory areas and neovascularization. Quantitative analysis showed that the average area with positive expression of ET-1 was 18.21±14.96%. For ETA and ETB, the mean expressed areas were respectively 15.06±13.13% and 9.20±11.09%. ET-3 did not have a significant expression. The correlation between the expression of both endothelin receptors were strongly positive (R=0.74, P=0.02), but the correlation between ET-1 and its receptor were negative for both ETA (R=-0.37, P=0.25), and ETB (R=-0.14, P=0.39). This data was supported by western blot analysis. Conclusion: The strong correlation between ET-1 and its receptors suggests that both play a role in the pathophysiology of rheumatic mitral valve stenosis and may potentially act as biomarkers of this disease. .

Resumo Introdução: A febre reumática representa um sério problema de saúde pública em países em desenvolvimento, com milhares de novos casos a cada ano. Ela é uma doença autoimune que ocorre em resposta à infecção por estreptococos do grupo A. Objetivo: O objetivo deste estudo foi avaliar a expressão proteica e imunohistoquímica para a endotelina-1 e 3 (ET-1 e ET-3) e seus receptores (ETA e ETB) em valvas mitrais reumáticas. Métodos: Imunohistoquímica foi utilizada para identificar receptores de ET1/ET3 e ETA/ETB em valvas mitrais reumáticas e controles. A análise quantitativa da expressão imunohistoquímica para receptores de ET1/ET3 e ETA/ETB foi também efetuada. Adicionalmente, foi feita análise do western blot para mensurar níveis de proteínas em extratos tissulares. Resultados: A expressão imunohistoquímica de ET-1 e de seu receptor predominou em valvas estenóticas, estando associada com regiões fibróticas, áreas inflamatórias e neovascularização. A análise quantitativa mostrou que a área média com expressão positiva para ET-1 foi de 18,21±14,96%. Para o ETA e o ETB, as áreas médias expressas foram, respectivamente, 15,06±13,13% e 9,20±11,09%. ET-3 não teve uma expressão significante. A correlação entre a expressão dos dois receptores de endotelina foi fortemente positiva (R=0,74, P=0,02); mas a correlação entre ET-1 e o seu receptor foi negativa tanto para ETA (R=-0,37, P=0,25) como para ETB (R=-0,14, P=0,39). Estes dados foram confirmados pela análise do western blot. Conclusão: A forte correlação entre ET-1 e seus receptores sugere que ambos têm papel importante na fisiopatologia da estenose mitral reumática, podendo potencialmente atuar como biomarcadores desta doença. .

Quantificação dos níveis de endotelina-1 em placentas e mebranas fetais humanas / Quantification of endothelin-1 level in placentae and human fetal membranes

A endotelina é um peptídeo vasoconstrictor potente que possui funções angiogênicas, mitogênicas e neurotróficas. Neste estudo procurou-se quantificar os níveis de Endotelina -1 (ET-1) em vilos coriônicos placentários e no âmnio de placentas de fetos gemelares, cujas mães submeteram-se à reprodução assistida e fecundação espontânea. Foram colhidas oito amostras de placentas, que após o delivramento placentário, foram colocadas em nitrogênio líquido e, posteriormente, congeladas e mantidas à -80°C até o processamento por ensaio imunoenzimático (ELISA). Os níveis de concentração de ET-1 em amostras de vilos coriônicos de placentas de fetos gemelares variaram de 0,52 a 0,70fmol/ml, enquanto que de fetos únicos variou de 0,47 a 0,86fmol/ml. A mesma determinação em amostras de âmnio de placentas de gemelares variou de 0,61 a 1,16 fmol/ml, enquanto que de fetos únicos variou de 0,65 a 1,04fmol/ml. Estes achados indicam que em vilos coriônicos, os níveis de concentração de ET-1 não variaram entre gemelares e fetos únicos. No âmnio, os níveis de ET-1 são mais elevados em gemelares que em fetos únicos, dados que sugerem que o âmnio é a principal fonte de ET-1 presente no líquido amniótico.

The endothelin is a potent vasoconstricor that possess angiogenic, mitogenic and neurotrophical functions. In this study we aimed to quantify the Endothelin-1 (ET-1) levels in chorionic placental villi and amnion of placentae of twins childbirths whose women were submitted to an assisted pregnancy and spontaneal fecundation. Were collected 08 placental samples. After the placental delivery the samples had been placed in liquid nitrogen and later in a -80°C until the Enzyme-Linked Immunosorbent Assay (ELISA) technique. The concentration levels of ET-1 in samples of chorionic villi in twins placentae varied from 0,52 to 0,70 fmol/ml, while in chorionic villi single gestation varied from 0,47 to 0,86 fmol/ml. The same determination in samples of amnion of twins placentae varied from 0,65 to 1,16 fmol/ml, while in single gestation varied from 0,65 to 1,04 fmol/ml. These findings suggests that in the chorionic villi the levels of ET-1 didn't vary between twins and single gestation. In the amnion the levels of ET-1 are higher in twins than in single gestation, suggesting that the amnion is the source of ET-1 in the amniotic fluid.