RESUMEN
OBJECTIVE: Mutations in the gonadotropin-releasing hormone receptor (GnRHR) gene are the cause of isolated hypogonadotropic hypogonadism (HH). We describe the molecular investigations of the GnRHR gene in two siblings affected by HH and their clinical course. DESIGN: The female was referred at age 14 for pubertal delay with no secondary sexual signs, whereas the male had been followed since prepuberty. Hormonal evaluation showed very low levels of gonadotropins, luteinizing hormone-releasing hormone test (LHRH test) and sexual steroids in both patients, suggesting a possible defect in the mechanism of action of the GnRH gene on its receptor. METHODS: The GnRHR gene of the two siblings and their parents were analyzed by PCR followed by direct sequencing. RESULTS: Two new single nucleotide substitutions resulting in the T104I and the Y108C substitutions in the first extracellular loop (ECL1) were identified in both siblings. The molecular analysis confirmed the carrier status of the parents. CONCLUSIONS: We identified two new missense mutations in the GnRHR gene in two siblings with HH. The nature of the substitutions lying in the ECL1 involved in the ligand-receptor interaction, as well as the high conservation of the two residues in all mammalian GnRHR, are suggestive of some implications in the phenotype observed.
Asunto(s)
Hipogonadismo/genética , Mutación Missense , Receptores LHRH/genética , Adolescente , Adulto , Femenino , Gonadotropinas/sangre , Humanos , Ligandos , Masculino , Embarazo , Receptores LHRH/metabolismo , HermanosRESUMEN
We report on a DAX1 gene investigation in a patient with X-linked adrenal hypoplasia congenita (AHC) and hypogonadotropic hypogonadism (HH) in order to identify mutations causing this disorder and to confirm the clinical diagnosis. The description of the clinical course of the condition with a detailed documentation of longitudinal data is also reported. A male newborn was referred at 45 days of life because of vomiting, dehydration, and weight loss. The diagnosis was primary adrenal insufficiency. The appropriateness of glucocorticoid therapy during the prepubertal period was difficult to judge because of elevated ACTH levels on one hand and progressive retardation of bone age on the other hand. Basal and GnRH stimulated gonadotropin levels remained low during the entire period of examination and exogenous gonadotropin treatment was begun. This had to be interrupted at age 14.6 years because of the occurrence of a 3rd degree anaplastic ependimoma of the left posterior-parietal region, without apparent lepto-meningeal involvement. The molecular analysis of DAX1 gene of the propositus showed deletion of nucleotides AAT in exon 2, resulting in the loss of the Asn430. No alterations were found in the mother and grandmother. This deleted residue lies in one of the helices forming the hydrophobic core of the ligand-binding domain (LBD); thus this mutation may be the cause of the observed phenotype. Further investigations are needed to verify its causal role in AHC associated with HH.
Asunto(s)
Enfermedades de las Glándulas Suprarrenales/genética , Proteínas de Unión al ADN/genética , Hipogonadismo/genética , Mutación , Receptores de Ácido Retinoico/genética , Proteínas Represoras/genética , Adolescente , Enfermedades de las Glándulas Suprarrenales/patología , Secuencia de Aminoácidos , Secuencia de Bases , Estatura/efectos de los fármacos , Niño , Preescolar , Receptor Nuclear Huérfano DAX-1 , ADN/química , ADN/genética , Análisis Mutacional de ADN , Femenino , Estudios de Seguimiento , Gonadotropinas/deficiencia , Gonadotropinas/uso terapéutico , Humanos , Hipogonadismo/patología , Lactante , Recién Nacido , Masculino , Linaje , Eliminación de SecuenciaRESUMEN
OBJECTIVES: We used acetylsalicylic acid (ASA) as a probing agent to quantify hydroxyl radical ((*)OH) in Controls and patients with coronary artery disease and to prospectively investigate (*)OH production in patients with myocardial infarction (MI) complicated by heart failure (HF). BACKGROUND: Oxidative stress status (OSS) is a mechanism for transition to HF in experimental heart injury models, but evidence for its causal role in humans is still limited. METHODS: Thirty healthy subjects (Controls), 12 patients with stable angina (Group 1), and 74 patients with ST-segment elevation MI (Group 2) were enrolled. A dose of 250 mg Flectadol was given intravenously before each blood collection to determine the 2,3-dihydroxybenzoic acid/salicylic acid (DHBA/SA) ratio. We also quantified vitamin E and coenzyme Q(10) to monitor antioxidant reserve, as well as tumor necrosis factor (TNF)-alpha, TNF-soluble receptors, interleukin (IL)-6, and IL-1ra to assess inflammatory status. All measurements were repeated at month 6 in Group 2. RESULTS: There were no differences between Controls and Group 1. Group 2 showed increased (*)OH production, peaking at 24 h, whereas vitamin E and coenzyme Q(10) progressively declined. Group 2 patients developing HF during hospitalization (Group 2Bi) presented with an increase of both (*)OH production at discharge and inflammatory status, as compared with patients without HF (Group 2Ai), persisting at month 6 in post-MI patients with HF (Group 2Bii). CONCLUSIONS: We found a distinct pattern of (*)OH generation in post-MI patients who show progression to HF. The interplay between OSS and inflammatory status should be targeted as a possible mechanism of progression to post-MI left ventricular dysfunction.
Asunto(s)
Insuficiencia Cardíaca/complicaciones , Radical Hidroxilo/sangre , Infarto del Miocardio/complicaciones , Factor de Necrosis Tumoral alfa/metabolismo , Anciano , Estudios de Casos y Controles , Progresión de la Enfermedad , Etanercept , Femenino , Insuficiencia Cardíaca/sangre , Humanos , Inmunoglobulina G/sangre , Proteína Antagonista del Receptor de Interleucina 1 , Interleucina-6/sangre , Masculino , Infarto del Miocardio/sangre , Estudios Prospectivos , Receptores del Factor de Necrosis Tumoral/sangre , Sialoglicoproteínas/sangreRESUMEN
To investigate whether ursodeoxycholic acid (UDCA) can prevent metabolic impairment induced by deoxycholic acid (DCA), we evaluated the effects of these bile acids on murine CYP enzymes and the relationship with canalicular bile salt export pump (Bsep) expression. In Swiss Albino CD1 mice, UDCA and DCA were injected intraperitoneally either singly, concurrently, or sequentially (UDCA 1 hour before DCA) at equimolar 24.4 mg/kg body weight (BW) doses. CYP content, NADPH-CYP-c-reductase, and individual mixed function oxidases (MFO) were measured 24 hours later. Modulations were observed mainly in males: whereas DCA decreased MFO activities to various isoenzymes with respect to controls (up to 43%, CYP1A2-linked activity), UDCA boosted them (up to 6-fold, testosterone 16 beta-hydroxylase); concurrent administration of UDCA and DCA provided a preventive effect, enhancing MFO activity with respect to single administration of DCA by up to 4.4-fold in the CYP3A1/2 and CYP2B1/2 (6 beta-hydroxylase) and by 2.1-fold in the CYP2E1 (p-nitrophenol hydroxylase). In males (but not females), sequential administration (UDCA then DCA) produced a rather similar protective pattern, but the extent of recovery was generally smaller. Western immunoblotting results for the most affected isoenzymes (CYP3A1/2 and CYP2E1) and Bsep confirmed that UDCA can both prevent and reduce the CYP-dependent MFO inactivation and Bsep down-regulation caused by DCA. These findings may shed further light on the mechanisms responsible for UDCA's protective role in the treatment of cholestatic liver disease.