Zinc alpha-2 glycoprotein is overproduced in Cushing's syndrome.

INTRODUCTION: Cushing syndrome (CS), an endogenous hypercortisolemic condition with increased cardiometabolic morbidity, leads to development of abdominal obesity, insulin resistance, diabetes and proatherogenic dyslipidemia. Zinc alpha-2 glycoprotein (ZAG) is a recently characterized lipolytic adipokine implicated in regulation of adipose tissue metabolism and fat distribution. In vitro and animal studies suggest that glucocorticoids interact with ZAG secretion and action. To assess the relationship between ZAG and glucocorticoids in a human model of hypercortisolism, circulating ZAG levels were tested in patients with CS and its counterpart controls. METHODS: An observational, cross-sectional study on 39 women, 13 with active CS and 26 controls matched by age and body mass index. Plasma ZAG levels (µg/ml) were measured by ELISA and correlated with hypercortisolism, metabolic, and phenotypic parameters. RESULTS: Plasma ZAG levels were significantly higher in patients with CS compared to controls (64.3±16.6 vs. 44.0±16.1, p=0.002). In a univariate analysis, ZAG levels positively correlated to 24-h urinary free cortisol (p=0.001), body mass index (p=0.02), non-esterified fatty acids (p=0.05), glucose (p=0.003), LDL-C (p=0.028), and type 2 diabetes mellitus (p=0.016), and were inversely related to total adiponectin levels (p=0.035). In a multivariate analysis, after adjusting for CS, ZAG levels only correlated with body mass index (p=0.012), type 2 diabetes mellitus (p=0.004), and glucose (p<0.001). CONCLUSION: This study provides initial evidence that plasma ZAG levels are higher in patients with CS as compared to controls. The close relationship of ZAG with metabolic and phenotypic changes in CS suggests that ZAG may play a significant role in adipose tissue changes in hypercortisolism.

Zinc alpha-2 glycoprotein is overproduced in Cushing's syndrome / Aumento de la glucoproteína zinc alfa-2 en el síndrome de Cushing

Introduction: Cushing syndrome (CS), an endogenous hypercortisolemic condition with increased cardiometabolic morbidity, leads to development of abdominal obesity, insulin resistance, diabetes and proatherogenic dyslipidemia. Zinc alpha-2 glycoprotein (ZAG) is a recently characterized lipolytic adipokine implicated in regulation of adipose tissue metabolism and fat distribution. In vitro and animal studies suggest that glucocorticoids interact with ZAG secretion and action. To assess the relationship between ZAG and glucocorticoids in a human model of hypercortisolism, circulating ZAG levels were tested in patients with CS and its counterpart controls. Methods: An observational, cross-sectional study on 39 women, 13 with active CS and 26 controls matched by age and body mass index. Plasma ZAG levels (μg/ml) were measured by ELISA and correlated with hypercortisolism, metabolic, and phenotypic parameters. Results: Plasma ZAG levels were significantly higher in patients with CS compared to controls (64.3±16.6 vs. 44.0±16.1, p=0.002). In a univariate analysis, ZAG levels positively correlated to 24-h urinary free cortisol (p=0.001), body mass index (p=0.02), non-esterified fatty acids (p=0.05), glucose (p=0.003), LDL-C (p=0.028), and type 2 diabetes mellitus (p=0.016), and were inversely related to total adiponectin levels (p=0.035). In a multivariate analysis, after adjusting for CS, ZAG levels only correlated with body mass index (p=0.012), type 2 diabetes mellitus (p=0.004), and glucose (p<0.001). Conclusion: This study provides initial evidence that plasma ZAG levels are higher in patients with CS as compared to controls. The close relationship of ZAG with metabolic and phenotypic changes in CS suggests that ZAG may play a significant role in adipose tissue changes in hypercortisolism (AU)

Introducción: El síndrome de Cushing (SC) es un estado de hipercortisolismo endógeno en el que se observa un incremento del riesgo cardiovascular asociado al desarrollo de obesidad abdominal, insulinorresistencia, diabetes y dislipidemia aterogénica. La zinc alfa-2 glucoproteína (ZAG) es una adipocina lipolítica recientemente caracterizada que está implicada en la regulación del metabolismo del tejido adiposo y la distribución de la grasa. Estudios in vitro y en animales indican que los glucocorticoides interaccionan con la secreción y acción de ZAG. Para evaluar la relación entre ZAG y los glucocorticoides en un modelo humano de hipercortisolismo, se analizaron los niveles circulantes de ZAG en pacientes con SC y sus correspondientes controles. Métodos: Estudio observacional en 39 mujeres, 13 con SC activo y 26 controles pareadas por edad e índice de masa corporal. Los niveles plasmáticos de ZAG (μg/ml) se determinaron mediante ELISA y se correlacionaron con los parámetros de hipercortisolismo, metabólicos y fenotípicos. Resultados: Las concentraciones plasmáticas de ZAG fueron significativamente más elevadas en los pacientes con SC (64,3±16,6 vs. 44±16,1; p=0,002). En el análisis univariante los niveles de ZAG se correlacionaron positivamente con cortisol libre urinario (p=0,001), índice de masa corporal (p=0,02), ácidos grasos no esterificados (p=0,05), glucosa (p=0,003), c-LDL (p=0,028) y diabetes mellitus (p=0,016) e inversamente con adiponectina total (p=0,035). En el análisis multivariante, después de ajustar por el SC, los niveles de ZAG solo se correlacionaron con el índice de masa corporal (p=0,012), la diabetes mellitus tipo 2 (p=0,004) y la glucosa (p<0,001). Conclusión: Nuestro estudio proporciona la primera evidencia de las concentraciones plasmáticas de ZAG en el SC. Los pacientes con SC presentan concentraciones más elevadas de ZAG que los controles. La estrecha relación de ZAG con las alteraciones metabólicas y fenotípicas del SC indica que ZAG podría desempeñar un papel importante en las alteraciones del tejido adiposo en el hipercortisolismo (AU)

New splice site acceptor mutation in AIRE gene in autoimmune polyendocrine syndrome type 1.

Autoimmune polyglandular syndrome type 1 (APS-1, OMIM 240300) is a rare autosomal recessive disorder, characterized by the presence of at least two of three major diseases: hypoparathyroidism, Addison's disease, and chronic mucocutaneous candidiasis. We aim to identify the molecular defects and investigate the clinical and mutational characteristics in an index case and other members of a consanguineous family. We identified a novel homozygous mutation in the splice site acceptor (SSA) of intron 5 (c.653-1G>A) in two siblings with different clinical outcomes of APS-1. Coding DNA sequencing revealed that this AIRE mutation potentially compromised the recognition of the constitutive SSA of intron 5, splicing upstream onto a nearby cryptic SSA in intron 5. Surprisingly, the use of an alternative SSA entails the uncovering of a cryptic donor splice site in exon 5. This new transcript generates a truncated protein (p.A214fs67X) containing the first 213 amino acids and followed by 68 aberrant amino acids. The mutation affects the proper splicing, not only at the acceptor but also at the donor splice site, highlighting the complexity of recognizing suitable splicing sites and the importance of sequencing the intron-exon junctions for a more precise molecular diagnosis and correct genetic counseling. As both siblings were carrying the same mutation but exhibited a different APS-1 onset, and one of the brothers was not clinically diagnosed, our finding highlights the possibility to suspect mutations in the AIRE gene in cases of childhood chronic candidiasis and/or hypoparathyroidism otherwise unexplained, especially when the phenotype is associated with other autoimmune diseases.