Correlación entre osteocalcina, insulinorresistencia, insulinosensibilidad y metabolismo de la glucosa en adultos mayores con síndrome metabólico / Correlation between Osteocalcin, Insulin Resistance, Insulin Sensitivity and Carbohydrate Metabolism in an Elderly Population with Metabolic Syndrome

Introducción: Recientemente han surgido nuevas evidencias que relacionan el metabolismo óseo con el energético. La osteocalcina es una proteína de la matriz ósea no colágena, sintetizada por los osteoblastos que modula localmente la mineralización ósea, tradicionalmente usada como marcador de formación ósea. Se ha demostrado tanto en modelos "in vitro" como en animales de experimentación que la osteocalcina tiene acción hormonal. Esta proteína tiene la propiedad de regular la insulinosensibilidad, la insulinosecreción y la proliferación de las células beta pancreáticas. Objetivo: Evaluar la existencia de correlación entre los niveles de osteocalcina sérica y marcadores de insulinorresistencia (IR) e insulinosensibilidad en una población de adultos mayores con síndrome metabólico. Material y métodos: En nuestro estudio prospectivo se incluyeron 88 pacientes (68 % mujeres, 32 % hombres, media de edad 73 ± 6 y 74 ± 6 años respectivamente) que concurrieron a los consultorios externos del servicio de Endocrinología y Metabolismo del hospital Dr. César Milstein. Todos cumplían con los criterios diagnósticos de síndrome metabólico del año 2009 de la Federación Internacional de Diabetes (IDF). Se midieron: osteocalcina sérica, hemoglobina glicosilada (HbA1c), HDL y triglicéridos (TG). Se calcularon QUICKI (Quantitative Insulin Sensivity Check Index) y el índice TG/HDL. Resultados: Los niveles de osteocalcina sérica se asociaron positivamente con HDL (r = 0,213, p = 0,05) y QUICKI (r = 0,212, p = 0,05) e inversamente con TG (r = -0,218, p < 0,05), con el índice TG/HDL (r = -0,217, p < 0,05) y con HbA1c (r = -0,253, p < 0,05). Conclusiones: Nuestro estudio mostró que en adultos mayores con sindrome metabólico, los niveles de osteocalcina reducidos se asociaron con un aumento en los índices de insulinorresistencia, una disminución de los de insulinosensibilidad y un peor control metabólico. Rev Argent Endocrinol Metab 52:8-13, 2015 Los autores no poseen conflictos de interés.(AU)

Introduction: In recent years there has been increasing evidence about the relationship between bone and energy metabolism. Osteocalcin is a non-collagenous bone matrix protein synthesized by osteoblasts that locally modulates bone mineralization and is traditionally used as a bone formation marker. Osteocalcin has been shown to have hormonal actions both in in vitro models and in experimental animals. This hormone has the property of regulating insulin secretion and insulin sensitivity as well as beta pancreatic cell proliferation. Aim: To evaluate the existence of correlation between serum osteocalcin levels, insulin resistance and insulin sensitivity markers in an elderly population with metabolic syndrome. Material and methods: Eighty-eight elderly patients were included in our prospective study (68 % women, mean age 73 ± 6 ; 32 % men, mean age 74 ± 6). They attended the outpatient Endocrinology and Metabo¡lism service at Dr. César Milstein Hospital and met the International Diabetes Federation (IDF) criteria of metabolic syndrome. Serum Osteocalcin, Glycated haemoglobin (HbA1c), HDL and Triglycerides (TG) were measured. QUICKI and TG/HDL index were calculated. Results: Serum osteocalcin levels were positively associated with HDL (r = 0.213, p = 0.05) and QUICKI (r = 0.212, p = 0.05), and inversely associated with TG (r = -0.218, p < 0.05), TG/HDL index (r = -0.217, p < 0.05) and HbA1c (r = -0.253, p < 0.05). Conclusions: Our study showed that in elderly patients with metabolic syndrome, reduced osteocalcin levels were associated with increased insulin sensitivity, decreased insulin resistance indexes and impaired metabolic control. Rev Argent Endocrinol Metab 52:8-13, 2015 No financial conflicts of interest exist.(AU)

Correlación entre osteocalcina, insulinorresistencia, insulinosensibilidad y metabolismo de la glucosa en adultos mayores con síndrome metabólico / Correlation between Osteocalcin, Insulin Resistance, Insulin Sensitivity and Carbohydrate Metabolism in an Elderly Population with Metabolic Syndrome

Introducción: Recientemente han surgido nuevas evidencias que relacionan el metabolismo óseo con el energético. La osteocalcina es una proteína de la matriz ósea no colágena, sintetizada por los osteoblastos que modula localmente la mineralización ósea, tradicionalmente usada como marcador de formación ósea. Se ha demostrado tanto en modelos "in vitro" como en animales de experimentación que la osteocalcina tiene acción hormonal. Esta proteína tiene la propiedad de regular la insulinosensibilidad, la insulinosecreción y la proliferación de las células beta pancreáticas. Objetivo: Evaluar la existencia de correlación entre los niveles de osteocalcina sérica y marcadores de insulinorresistencia (IR) e insulinosensibilidad en una población de adultos mayores con síndrome metabólico. Material y métodos: En nuestro estudio prospectivo se incluyeron 88 pacientes (68 % mujeres, 32 % hombres, media de edad 73 ± 6 y 74 ± 6 años respectivamente) que concurrieron a los consultorios externos del servicio de Endocrinología y Metabolismo del hospital Dr. César Milstein. Todos cumplían con los criterios diagnósticos de síndrome metabólico del año 2009 de la Federación Internacional de Diabetes (IDF). Se midieron: osteocalcina sérica, hemoglobina glicosilada (HbA1c), HDL y triglicéridos (TG). Se calcularon QUICKI (Quantitative Insulin Sensivity Check Index) y el índice TG/HDL. Resultados: Los niveles de osteocalcina sérica se asociaron positivamente con HDL (r = 0,213, p = 0,05) y QUICKI (r = 0,212, p = 0,05) e inversamente con TG (r = -0,218, p < 0,05), con el índice TG/HDL (r = -0,217, p < 0,05) y con HbA1c (r = -0,253, p < 0,05). Conclusiones: Nuestro estudio mostró que en adultos mayores con sindrome metabólico, los niveles de osteocalcina reducidos se asociaron con un aumento en los índices de insulinorresistencia, una disminución de los de insulinosensibilidad y un peor control metabólico. Rev Argent Endocrinol Metab 52:8-13, 2015 Los autores no poseen conflictos de interés.

Introduction: In recent years there has been increasing evidence about the relationship between bone and energy metabolism. Osteocalcin is a non-collagenous bone matrix protein synthesized by osteoblasts that locally modulates bone mineralization and is traditionally used as a bone formation marker. Osteocalcin has been shown to have hormonal actions both in in vitro models and in experimental animals. This hormone has the property of regulating insulin secretion and insulin sensitivity as well as beta pancreatic cell proliferation. Aim: To evaluate the existence of correlation between serum osteocalcin levels, insulin resistance and insulin sensitivity markers in an elderly population with metabolic syndrome. Material and methods: Eighty-eight elderly patients were included in our prospective study (68 % women, mean age 73 ± 6 ; 32 % men, mean age 74 ± 6). They attended the outpatient Endocrinology and Metabo­lism service at Dr. César Milstein Hospital and met the International Diabetes Federation (IDF) criteria of metabolic syndrome. Serum Osteocalcin, Glycated haemoglobin (HbA1c), HDL and Triglycerides (TG) were measured. QUICKI and TG/HDL index were calculated. Results: Serum osteocalcin levels were positively associated with HDL (r = 0.213, p = 0.05) and QUICKI (r = 0.212, p = 0.05), and inversely associated with TG (r = -0.218, p < 0.05), TG/HDL index (r = -0.217, p < 0.05) and HbA1c (r = -0.253, p < 0.05). Conclusions: Our study showed that in elderly patients with metabolic syndrome, reduced osteocalcin levels were associated with increased insulin sensitivity, decreased insulin resistance indexes and impaired metabolic control. Rev Argent Endocrinol Metab 52:8-13, 2015 No financial conflicts of interest exist.

Particularidades del síndrome metabólico en una subpoblación de adultos mayores / Particularities of metabolic syndrome in an elderly subpopulation

Introducción: El síndrome metabólico (SM) se define por un conjunto de alteraciones clínicas que aumentan el riesgo de enfermedad cardiovascular. Diferentes organizaciones internacionales de salud han ajustado progresivamente los criterios que definen al SM, con el consiguiente aumento del diagnóstico del mismo. Sin embargo, ninguno de los parámetros considerados se han adaptado a la edad ni se han tomado en cuenta las modificaciones antropométricas y metabólicas características del envejecimiento. Objetivo: Caracterizar al SM en una población de adultos mayores y evaluar si existen diferencias de género. Materiales y métodos: Se realizó un estudio prospectivo en pacientes que consultaron al Servicio de Endocrinología de la U. A. Dr. César Milstein. El 68,8 % fueron mujeres y la edad de la población fue 73 ± 6 años. Para el diagnóstico de SM se utilizaron los criterios del Joint Interim Statement de 2009. Recabamos información sobre antecedentes, medicación y se realizaron análisis de laboratorio. Se midió índice cintura/talla (ICT). Se calculó media ± desvío estándar (DS) y proporciones. Para establecer comparaciones entre varones y mujeres se utilizó Test de Student y test de Chi2. Resultados: En una muestra de 77 pacientes, 42,9 % cumplió con 3 componentes de SM, 33,8 % con 4 y 23,4 % con 5, con distribución similar en hombres y mujeres. Según el índice de masa corporal (IMC), 32,5 % de la población presentó sobrepeso; 35 % obesidad grado I; 22 % grado II y 9 % grado III. Al evaluar el perímetro de cintura (PC), el 98,7 % superó los puntos de corte. El índice cintura/ talla superó el valor normal en ambos sexos, siendo significativamente superior en las mujeres (p: 0,003). Conclusiones: En la población de adultos mayores que se estudió no se observó diferencia entre ambos sexos en el número de componentes diagnósticos de SM. En cuanto al perímetro de cintura, el valor fue similar en ambos sexos, lo que podría llevar a revisar el valor de corte del mismo en este grupo etario. El ICT estuvo aumentado en toda la población y por ser un subrogante de riesgo cardiovascular, sería otro parámetro a tener en cuenta al momento del diagnóstico de SM. Rev Argent Endocrinol Metab 51:130-135, 2014 Los autores no poseen conflictos de interés.

Introduction: The metabolic syndrome (MS) denotes an association of abnormalities that increase the risk of cardiovascular disease. With the intention of decreasing this risk, international organizations have dropped the normal range for various parameters, with a consequent increase in the diagnosis of MS. Although the changes related to age are well documented, none of these parameters has been age-adapted. Aims: to characterize MS in the elderly population and to establish possible gender differences. Materials and methods: We performed a prospective study in patients who presented at the Department of Endocrinology of the Healthcare Unit Dr. Cesar Milstein. Of the total population, 68.8 % were women and the average age was 73 ± 6 years. For the diagnosis of MS, we used the 2009 Joint Interim Statement diagnostic criteria. Information was collected on previous history and medication, and laboratory analyses were performed. The waist / height ratio was also measured. Mean ± standard deviation (SD) and proportions were calculated. For comparisons between men and women, the Student test and Chi-squared test were used. Results: Of the total population, 42.9 % fulfilled 3 criteria for MS, 33.8 % fulfilled 4 criteria and 23.4 % fulfilled 5, with similar distribution in men and women. According to body mass index (BMI), 32.5 % of the population had overweight, 35 % were grade I obese, 22 % were grade II and 9 % were grade III. As regards waist circumference, 98.7 % of the total population exceeded the established cutoffs. The waist/ height ratio exceeded normal values in both genders, being significantly higher in women (p = 0.003). Conclusions: In the elderly, there are no gender differences in the number of components of MS. As for waist circumference, values were similar in both men and women. This finding could lead to redefine the cutoff value in aged woman. The waist / height ratio, a surrogate marker of cardiovascular disease, was ...

Autoinmunidad tiroidea: Mecanismos patogénicos comunes y distintivos en tiroiditis de Hashimoto y enfermedad de Graves / Thyroid Autoimmunity: Common and Distinctive Pathogenic Mechanisms in Hashimotos Thyroiditis and Graves Disease

Las enfermedades tiroideas autoinmunes (ETA) son los desórdenes más frecuentes que llevan a la disfunción de la glándula tiroidea. Incluyen varias formas clínicas como Tiroiditis de Hashimoto (TH) y Enfermedad de Graves (EG). La relación entre TH y EG ha sido objeto de debate por décadas. Si bien, muy diferentes en su clínica, algunos las consideran los lados opuestos de una misma moneda. En su patogénesis tienen aspectos en común, como la predisposición genética demostrado por la ocurrencia en una misma familia y en un mismo individuo. Sin embargo, diferencias en el microambiente local determinan la diferente expresión fenotípica o el viraje de una a otra patología. El objetivo de esta monografía es investigar similitudes y diferencias entre TH y EG en las distintas etapas que llevan al desarrollo de autoinmunidad. Los autores declaran no poseer conflictos de interés.(AU)

Autoimmune thyroid disease (ATD) is the most common disorder that leads to thyroid gland dysfunction. ATD manifests in various clinical forms, such as Hashimotos Thyroiditis (HT) and Graves Disease (GD). The relation between HT and GD has been discussed for decades. Even if they greatly differ in their clinical features and treatment, some people believe they are the opposite sides of the same coin. In their pathogenesis, they share some mechanisms, such as genetic susceptibility, shown by the fact that they tend to occur both in the same person and within the same family. However, differences in the local micro-environment can determine the distinct phenotypic expression or the switch from one disease to the other. The aim of this monograph was to investigate similarities and differences between HT and GD at the diverse stages leading to the development of autoimmunity. No financial conflicts of interest exist.(AU)

Autoinmunidad tiroidea: Mecanismos patogénicos comunes y distintivos en tiroiditis de Hashimoto y enfermedad de Graves / Thyroid Autoimmunity: Common and Distinctive Pathogenic Mechanisms in Hashimoto's Thyroiditis and Graves' Disease

Las enfermedades tiroideas autoinmunes (ETA) son los desórdenes más frecuentes que llevan a la disfunción de la glándula tiroidea. Incluyen varias formas clínicas como Tiroiditis de Hashimoto (TH) y Enfermedad de Graves (EG). La relación entre TH y EG ha sido objeto de debate por décadas. Si bien, muy diferentes en su clínica, algunos las consideran los lados opuestos de una misma moneda. En su patogénesis tienen aspectos en común, como la predisposición genética demostrado por la ocurrencia en una misma familia y en un mismo individuo. Sin embargo, diferencias en el microambiente local determinan la diferente expresión fenotípica o el viraje de una a otra patología. El objetivo de esta monografía es investigar similitudes y diferencias entre TH y EG en las distintas etapas que llevan al desarrollo de autoinmunidad. Los autores declaran no poseer conflictos de interés.

Autoimmune thyroid disease (ATD) is the most common disorder that leads to thyroid gland dysfunction. ATD manifests in various clinical forms, such as Hashimoto's Thyroiditis (HT) and Graves' Disease (GD). The relation between HT and GD has been discussed for decades. Even if they greatly differ in their clinical features and treatment, some people believe they are the opposite sides of the same coin. In their pathogenesis, they share some mechanisms, such as genetic susceptibility, shown by the fact that they tend to occur both in the same person and within the same family. However, differences in the local micro-environment can determine the distinct phenotypic expression or the switch from one disease to the other. The aim of this monograph was to investigate similarities and differences between HT and GD at the diverse stages leading to the development of autoimmunity. No financial conflicts of interest exist.

Characterization of sex hormone-binding globulin isoforms in hypothyroid women.

Liver sex hormone-binding globulin (SHBG) biosynthesis is regulated by triiodothyronine (T3). This regulation is responsible for increased serum SHBG concentrations in hyperthyroid states. However, in hypothyroidism, normal SHBG levels are frequently found. To understand this we have characterized circulating SHBG isoforms according to their sialic acid content, which determines its half-life, in euthyroid and hypothyroid women. Six euthyroid (aged 56 +/- 8 years) and five hypothyroid women (51 +/- 13 years) were studied. Their body mass index (BMI) range was 20-25. Hypothyroidism diagnosis was based on clinical findings, elevated basal thyrotropin (TSH) and decreased T3 and thyroxine (T4) values. Total SHBG was measured by radioimmunoassay (RIA) and SHBG isoforms were isolated using preparative isoelectrofocusing. For comparisons, two-tailed t test was applied. No statistical difference was found between the total SHBG levels of hypothyroid and euthyroid postmenopausal women. Three groups of SHBG isoforms were isolated in the euthyroid group: S(I): pl: 5.0-5.2: 20% +/- 4%, S(II) : pl 5.2-5.4: 50% +/- 3% and S(III): pl 5.4-5.6: 29% +/- 4%. In hypothyroid patients, although the three groups of isoforms were isolated in the same pH range, S(I) and S(II) proportions were different (p < 0.001) when compared to normal women: S(I): 34% +/- 4%, S(II): 33% +/- 9.9% and S(III): 29% +/- 5.7%. These results show that hypothyroid patients have a higher proportion of more acidic SHBG isoforms. This variation may explain the normal levels of serum SHBG observed in hypothyroidism.

Variations of sex hormone-binding globulin in thyroid dysfunction.

With the aim of understanding the variations of the levels of sex hormone-binding globulin (SHBG) in thyroid dysfunction, we studied the influence of factors that also modify SHBG, such as menopausal status, age, and body mass index (BMI) in women with hypothyroidism and hyperthyroidism, both overt and subclinical. Statistical analysis was performed by means of analysis of variance (ANOVA), stepwise multiple regression, and partial correlation. The ANOVA showed a significant statistical difference among the means of SHBG of all groups (p<0.01). The difference was due to the group that included hyperthyroid women. Multiple regression analysis showed that the main factors influencing SHBG were BMI and age, except for the hyperthyroid group, where the most important independent variables were triiodothyronine (T3) and thyroxine (T4). Partial correlation controlling the effect of BMI and age showed no association between SHBG and the other variables in all groups except for the subclinical hyperthyroid and hyperthyroid, where we found a significant association between SHBG and T4 and T3. The premenopausal or postmenopausal status did not modify SHBG levels. When the patients are taken as a whole, BMI, age, T4, and T3 all have an association with SHBG levels according to the multiple regression analysis.