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1.
Anal Bioanal Chem ; 410(2): 407-416, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29110028

RESUMO

In the clinical laboratories, dehydroepiandrostenedione (DHEA) is usually quantified by immunoassay-based methods, which are often affected by cross-reactivity with endogenous interferences, such as 4-androsten-3ß-ol-17-one. The interfering compounds lead to a poor accuracy of the measurements, mainly at a low concentration level. The present paper describes a validated method based on tandem mass spectrometry coupled to liquid chromatography, for the accurate quantification of DHEA in serum. The peculiarity of this method is the use of calibrators and quality controls prepared by adding measured amounts of DHEA-D5, a stable isotope-labeled analogue of DHEA, to real serum from healthy subjects. DHEA-D5 is used in place of DHEA, which is usually present in unstripped serum at physiological levels, as it has the same basic structure, provides an equivalent instrumental response, and can be easily distinguish by DHEA by mass spectrometry due to its different m/z value. The method proved to be sensitive, with a LLOD of 0.09 ng/mL and a LLOQ of 0.23 ng/mL, and selective, with overall performances that allow its use on a routine basis.


Assuntos
Desidroepiandrosterona/sangue , Espectrometria de Massas em Tandem/métodos , Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Desidroepiandrosterona/análogos & derivados , Deutério/análise , Deutério/sangue , Humanos , Cinética , Limite de Detecção
2.
Endocrine ; 56(2): 426-437, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27515804

RESUMO

To investigate whether long-term, chronic treatment with the phosphodiesterase-5 inhibitor vardenafil affects adrenal and testicular steroidogenesis in diabetic men, using liquid chromatography-tandem mass spectrometry. A longitudinal, prospective, investigator-started, randomized, placebo-controlled, double-blind, clinical-trial was carried out, enrolling 54 male patients affected by type 2 diabetes mellitus diagnosed within the last 5 years. In total, 26 and 28 patients were followed for 1 year and assigned to the study and placebo group, respectively. Progesterone, 17-hydroxyprogesterone, androstenedione, testosterone, dehydroepiandrosterone, dehydroepiandrosterone sulfate, corticosterone, 11-deoxycortisol and cortisol, were evaluated using liquid chromatography-tandem mass spectrometry. No differences were seen in sex testicular steroids between study and control group. As for the adrenal gland, steroids were considered according to the zona in which they are produced. No significant differences were seen in steroid produced in zona fasciculata. For the zona reticularis, dehydroepiandrosterone significantly decreased during treatment only in the study group (p = 0.007), with higher levels at visit 2 and 8 than other visits. The dehydroepiandrosterone sulfate/dehydroepiandrosterone ratio significantly increased during treatment only in the verum group. Considering the adrenal zona glomerulosa, corticosterone significantly changed among visits both in both groups (p < 0.001), with higher levels at visit 2 (p = 0.028), 8 (p = 0.003), and 10 (p = 0.044), i.e., in coincidence with the complete clinical and instrumental examination performed only at these visits according to the study protocol. Chronically administered vardenafil reduces dehydroepiandrosterone levels and increases dehydroepiandrosterone sulfate/dehydroepiandrosterone ratio as possible consequences of modulation of steroidogenic enzymes by tissue changes in cyclic adenosine monophosphate and cyclic guanosine monophosphate availability. A possibly stress-related increase in corticosterone is suggested for the first time.


Assuntos
Androgênios/sangue , Corticosterona/sangue , Diabetes Mellitus Tipo 2/sangue , Hidrocortisona/sangue , Progesterona/sangue , Dicloridrato de Vardenafila/administração & dosagem , 17-alfa-Hidroxiprogesterona/sangue , Androstenodiona/sangue , Cromatografia Líquida , Método Duplo-Cego , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Espectrometria de Massas em Tandem , Testosterona/sangue
3.
Eur J Endocrinol ; 174(4): 513-22, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26792933

RESUMO

OBJECTIVE: Type 2 diabetes mellitus (T2DM) is associated with endothelial dysfunction, characterized by a reduction of nitric oxide (NO)-mediated relaxation. Phosphodiesterase type 5 inhibitors (PDE5i) improve NO levels. The aim of the study was to investigate whether long-term, chronic treatment with the PDE5i vardenafil improves systemic endothelial function in diabetic men. DESIGN: A prospective, investigator-initiated, randomized, placebo-controlled, double-blind, clinical trial was conducted. METHODS: In total, 54 male patients affected by T2DM, diagnosed within the last 5 years, and erectile dysfunction were enrolled, regardless of testosterone levels. In all, 26 and 28 patients were assigned to verum and placebo groups respectively. The study consisted of an enrollment phase, a treatment phase (24 weeks) (vardenafil/placebo 10  mg twice in a day) and a follow-up phase (24 weeks). Parameters evaluated were as follows: International Index of Erectile Function 15 (IIEF-15), flow-mediated dilation (FMD), serum interleukin 6 (IL6), endothelin 1 (ET-1), gonadotropins and testosterone (measured by liquid chromatography/tandem mass spectrometry). RESULTS: IIEF-15 erectile function improved during the treatment (P<0.001). At the end of the treatment both FMD (P=0.040) and IL6 (P=0.019) significantly improved. FMD correlated with serum testosterone levels (R(2)=0.299; P<0.001). Testosterone increased significantly under vardenafil treatment and returned in the eugonadal range only in hypogonadal men (n=13), without changes in gonadotropins. Chronic vardenafil treatment did not result in relevant side effects. CONCLUSION: This is the first double-blind, placebo-controlled clinical trial designed to evaluate the effects of chronic treatment of vardenafil on endothelial health-related parameters and sexual hormones in patients affected by a chronic disease. Chronically administered vardenafil is effective and improves endothelial parameters in T2DM patient. Moreover, chronic vardenafil therapy improves hypogonadism in diabetic, hypogonadal men.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Endotélio Vascular/efeitos dos fármacos , Disfunção Erétil/tratamento farmacológico , Hipogonadismo/tratamento farmacológico , Inflamação/sangue , Dicloridrato de Vardenafila/administração & dosagem , Idoso , Biomarcadores/sangue , Proteína C-Reativa/análise , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Método Duplo-Cego , Esquema de Medicação , Endotélio Vascular/patologia , Disfunção Erétil/sangue , Disfunção Erétil/complicações , Humanos , Hipogonadismo/sangue , Hipogonadismo/complicações , Inflamação/patologia , Molécula 1 de Adesão Intercelular/sangue , Interleucina-6/sangue , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Dicloridrato de Vardenafila/efeitos adversos , Molécula 1 de Adesão de Célula Vascular/sangue
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