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1.
Diabetes Care ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652656

RESUMO

OBJECTIVE: To explore the complementary effects of a combination of dipeptidyl peptidase 4 and sodium-glucose cotransporter 2 inhibitors added to metformin on hormonal and metabolic responses to meal ingestion. RESEARCH DESIGN AND METHODS: Forty-five patients (age 58 ± 8 years; HbA1c 58 ± 6 mmol/mol; BMI 30.7 ± 3.2 kg/m2) with type 2 diabetes uncontrolled with metformin were evaluated at baseline and 3 and 28 days after 5 mg saxagliptin (SAXA), 10 mg dapagliflozin (DAPA), or 5 mg saxagliptin plus 10 mg dapagliflozin (SAXA+DAPA) using a mixed-meal tolerance test (MMTT) spiked with dual-tracer glucose to assess glucose metabolism, insulin secretion, and sensitivity. RESULTS: At day 3, fasting and mean MMTT glucose levels were lower with SAXA+DAPA (-31.1 ± 1.6 and -91.5 ± 12.4 mg/dL) than with SAXA (-7.1 ± 2.1 and -53 ± 10.5 mg/dL) or DAPA (-17.0 ± 1.1 and -42.6 ± 10.0 mg/dL, respectively; P < 0.001). Insulin secretion rate (SAXA+DAPA +75%; SAXA +11%; DAPA 3%) and insulin sensitivity (+2.2 ± 1.7, +0.4 ± 0.7, and +0.4 ± 0.4 mg ⋅ kg-1⋅ min-1, respectively) improved with SAXA+DAPA (P < 0.007). Mean glucagon-like peptide 1 (GLP-1) was higher with SAXA+DAPA than with SAXA or DAPA. Fasting glucagon increased with DAPA and SAXA+DAPA but not with SAXA. Fasting endogenous glucose production (EGP) increased with SAXA+DAPA and DAPA. During MMTT, EGP suppression was greater (48%) with SAXA+DAPA (vs. SAXA 44%; P = 0.02 or DAPA 34%; P = 0.2). Metabolic clearance rate of glucose (MCRglu) increased more with SAXA+DAPA. At week 4, insulin secretion rate, ß-cell glucose sensitivity, and insulin sensitivity had further increased in the SAXA+DAPA group (P = 0.02), with no additional changes in GLP-1, glucagon, fasting or MMTT EGP, or MCRglu. CONCLUSIONS: SAXA+DAPA provided superior glycemic control compared with DAPA or SAXA, with improved ß-cell function, insulin sensitivity, GLP-1 availability, and glucose clearance.

2.
Diabetes Care ; 47(2): 246-251, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38055929

RESUMO

OBJECTIVE: To explore the associations among mannose, indexes of insulin resistance (IR) and secretion, and long-term cardiovascular outcomes. RESEARCH DESIGN AND METHODS: Fasting mannose was assayed in 1,403 participants, one-half of which had a first myocardial infarction (MI) with either normal glucose tolerance (n = 1,045) or newly detected dysglycemia (i.e., impaired glucose tolerance or type 2 diabetes; n = 358). Regression models were used to explore mannose associations with surrogate indexes of IR/insulin secretion. Multivariate Cox models were used to investigate the independent association between high (higher quartile) versus low (lower three quartiles) mannose and major adverse cardiac events (MACE) (n = 163) during the 10-year follow-up. RESULTS: Mannose was independently associated with IR indexes (all P ≤ 0.001). High versus low mannose was independently associated with MACE (hazard ratio 1.54, 95% CI 1.07-2.20) in the overall population. CONCLUSIONS: Mannose might represent a new biomarker able to track early, potentially detrimental glucometabolic alterations independently of glycemic state.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Infarto do Miocárdio , Humanos , Diabetes Mellitus Tipo 2/epidemiologia , Manose , Glicemia , Fatores de Risco , Infarto do Miocárdio/epidemiologia
3.
Cardiovasc Diabetol ; 21(1): 195, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-36151569

RESUMO

BACKGROUND: Plasma mannose, an emerging novel biomarker of insulin resistance, is associated with both diabetes mellitus and coronary atherosclerosis, but the relationship between mannose concentrations and myocardial infarction (MI) across different glycaemic states remains to be elucidated. The aim of this study was to investigate the independent association between mannose and a first MI in a group of subjects characterized according to their glycaemic state. METHODS: Fasting plasma mannose concentrations were analysed in 777 patients 6-10 weeks after a first myocardial infarction and in 770 matched controls by means of high-performance liquid chromatography coupled to tandem mass spectrometry. Participants without known diabetes mellitus were categorized by an oral glucose tolerance test (OGTT) as having normal glucose tolerance (NGT, n = 1045), impaired glucose tolerance (IGT, n = 246) or newly detected type 2 diabetes (T2DM, n = 112). The association between mannose and MI was investigated across these glycaemic states by logistic regression. RESULTS: Mannose levels increased across the glycaemic states (p < 0.0001) and were significantly associated with a first MI in the whole study population (odds ratio, OR: 2.2; 95% CI 1.4 to - 3.5). Considering the different subgroups separately, the association persisted only in subjects with NGT (adjusted OR: 2.0; 95% CI 1.2-3.6), but not in subgroups with glucose perturbations (adjusted OR: 1.8, 95% CI 0.8-3.7). CONCLUSIONS: Mannose concentrations increased across worsening levels of glucose perturbations but were independently associated with a first MI only in NGT individuals. Thus, mannose might be a novel, independent risk marker for MI, possibly targeted for the early management of previously unidentified patients at high cardiovascular risk.


Assuntos
Diabetes Mellitus Tipo 2 , Intolerância à Glucose , Resistência à Insulina , Infarto do Miocárdio , Biomarcadores , Glicemia/análise , Estudos de Casos e Controles , Glucose , Humanos , Manose , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico
4.
Sci Rep ; 12(1): 11530, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35798828

RESUMO

N-acetylaspartate (NAA) is the second most abundant metabolite in the human brain; although it is assumed to be a proxy for a neuronal marker, its function is not fully elucidated. NAA is also detectable in plasma, but its relation to cerebral NAA levels, cognitive performance, or features of cerebral disease has not been investigated. To study whether circulating NAA tracks cerebral NAA levels, and whether circulating NAA correlates with cognitive function and features of cerebral small vessel disease (SVD). Two datasets were analyzed. In dataset 1, structural MRI was acquired in 533 subjects to assess four features of cerebral SVD. Cognitive function was evaluated with standardized test scores (N = 824). In dataset 2, brain 1H-MRS from the occipital region was acquired (N = 49). In all subjects, fasting circulating NAA was measured with mass spectrometry. Dataset 1: in univariate and adjusted for confounders models, we found no correlation between circulating NAA and the examined features of cerebral SVD. In univariate analysis, circulating NAA levels were associated inversely with the speed in information processing and the executive function score, however these associations were lost after accounting for confounders. In line with the negative findings of dataset 1, in dataset 2 there was no correlation between circulating and central NAA or total NAA levels. This study indicates that circulating NAA levels do not reflect central (occipital) NAA levels, cognitive function, or cerebral small vessel disease in man.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Cognição , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Humanos
5.
Int J Cardiol ; 346: 86-92, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34800594

RESUMO

BACKGROUND: High mannose has previously associated with insulin resistance and cardiovascular disease (CVD). Our objective is to establish whether mannose is associated with anatomical evidence of coronary artery disease (CAD). METHODS: Plasma mannose concentrations were measured by liquid chromatography/tandem mass spectrometry in a discovery cohort (n = 513) and a validation cohort (n = 221) of carefully phenotyped individuals. In both cohorts CAD was quantitated using state-of-the-art imaging techniques (coronary computed coronary tomography angiography (CCTA), invasive coronary angiography and optical coherence tomography). Information on subsequent CVD events/death was collected. Associations of mannose with angiographic variables and biomarkers were tested using univariate and multivariate regression models. Survival analysis was performed using the Kaplan-Meier estimator. RESULTS: Mannose was related to indices of CAD and features of plaque vulnerability. In the discovery cohort, mannose was a marker of quantity and quality of CCTA-proven CAD and subjects with a mannose level in the top quartile had a significantly higher risk of CVD events/death (p = 3.6e-5). In the validation cohort, mannose was significantly associated with fibrous cap thickness < 65 µm (odds ratio = 1.32 per each 10 µmol/L mannose change [95% confidence interval, 1.05-1.65]) and was an independent predictor of death (hazard ratio for mannose≥vs < 84.6 µmol/L: 4.0(95%CI, 1.4-11.3), p = 0.006). CONCLUSION: The current data add novel evidence that high mannose is a signature of CAD with a vulnerable plaque phenotype, consistently across measures of severity of vessel involvement and independent of the traditional correlates of CVD, and that it is an independent predictor of incident adverse outcomes.


Assuntos
Doença da Artéria Coronariana , Manose , Biomarcadores , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Humanos , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco , Índice de Gravidade de Doença
6.
Front Immunol ; 12: 745713, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35140702

RESUMO

Background: Hypovitaminosis D has been suggested to play a possible role in coronavirus disease 2019 (COVID-19) infection. Methods: The aim of this study is to analyze the relationship between vitamin D status and a biochemical panel of inflammatory markers in a cohort of patients with COVID-19. A secondary endpoint was to evaluate the correlation between 25OHD levels and the severity of the disease. Ninety-three consecutive patients with COVID-19-related pneumonia were evaluated from March to May 2020 in two hospital units in Pisa, in whom biochemical inflammatory markers, 25OHD levels, P/F ratio at nadir during hospitalization, and complete clinical data were available. Results: Sixty-five percent of patients presented hypovitaminosis D (25OHD ≤ 20 ng/ml) and showed significantly higher IL-6 [20.8 (10.9-45.6) vs. 12.9 (8.7-21.1) pg/ml, p = 0.02], CRP [10.7 (4.2-19.2) vs. 5.9 (1.6-8.1) mg/dl, p = 0.003], TNF-α [8.9 (6.0-14.8) vs. 4.4 (1.5-10.6) pg/ml, p = 0.01], D-dimer [0.53 (0.25-0.72) vs. 0.22 (0.17-0.35) mg/l, p = 0.002], and IL-10 [3.7 (1.8-6.9) vs. 2.3 (0.5-5.8) pg/ml, p = 0.03]. A significant inverse correlation was found between 25OHD and all these markers, even adjusted for age and sex. Hypovitaminosis D was prevalent in patients with severe ARDS, compared with the other groups (75% vs. 68% vs. 55%, p < 0.001), and 25OHD levels were lower in non-survivor patients. Conclusions: The relationship between 25OHD levels and inflammatory markers suggests that vitamin D status needs to be taken into account in the management of these patients. If vitamin D is a marker of poor prognosis or a possible risk factor with beneficial effects from supplementation, this still needs to be elucidated.


Assuntos
COVID-19 , SARS-CoV-2/metabolismo , Deficiência de Vitamina D , Vitamina D/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , COVID-19/sangue , COVID-19/mortalidade , Citocinas/sangue , Intervalo Livre de Doença , Feminino , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/mortalidade
7.
Diabetologia ; 63(11): 2423-2433, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32827269

RESUMO

AIMS/HYPOTHESIS: The glucosuria induced by sodium-glucose cotransporter 2 (SGLT2) inhibition stimulates endogenous (hepatic) glucose production (EGP), blunting the decline in HbA1c. We hypothesised that, in response to glucosuria, a renal signal is generated and stimulates EGP. To examine the effect of acute administration of SGLT2 inhibitors on EGP, we studied non-diabetic individuals who had undergone renal transplant with and without removal of native kidneys. METHODS: This was a parallel, randomised, double-blind, placebo-controlled, single-centre study, designed to evaluate the effect of a single dose of dapagliflozin or placebo on EGP determined by stable-tracer technique. We recruited non-diabetic individuals who were 30-65 years old, with a BMI of 25-35 kg/m2 and stable body weight (±2 kg) over the preceding 3 months, and HbA1c <42 mmol/mol (6.0%). Participants had undergone renal transplant with and without removal of native kidneys and were on a stable dose of immunosuppressive medications. Participants received a single dose of dapagliflozin 10 mg or placebo on two separate days, at a 5- to 14-day interval, according to randomisation performed by our hospital pharmacy, which provided dapagliflozin and matching placebo, packaged in bulk bottles that were sequentially numbered. Both participants and investigators were blinded to group assignment. RESULTS: Twenty non-diabetic renal transplant patients (ten with residual native kidneys, ten with bilateral nephrectomy) participated in the study. Dapagliflozin induced greater glucosuria in individuals with residual native kidneys vs nephrectomised individuals (8.6 ± 1.1 vs 5.5 ± 0.5 g/6 h; p = 0.02; data not shown). During the 6 h study period, plasma glucose decreased only slightly and similarly in both groups, with no difference compared with placebo (data not shown). Following administration of placebo, there was a progressive time-related decline in EGP that was similar in both nephrectomised individuals and individuals with residual native kidneys. Following dapagliflozin administration, EGP declined in both groups, but the differences between the decrement in EGP with dapagliflozin and placebo in the group with bilateral nephrectomy (Δ = 1.11 ± 0.72 µmol min-1 kg-1) was significantly lower (p = 0.03) than in the residual native kidney group (Δ = 2.56 ± 0.33 µmol min-1 kg-1). In the population treated with dapagliflozin, urinary glucose excretion was correlated with EGP (r = 0.34, p < 0.05). Plasma insulin, C-peptide, glucagon, prehepatic insulin:glucagon ratio, lactate, alanine and pyruvate concentrations were similar following placebo and dapagliflozin treatment. ß-Hydroxybutyrate increased with dapagliflozin treatment in the residual native kidney group, while a small increase was observed only at 360 min in the nephrectomy group. Plasma adrenaline (epinephrine) did not change after dapagliflozin and placebo treatment in either group. Following dapagliflozin administration, plasma noradrenaline (norepinephrine) increased slightly in the residual native kidney group and decreased in the nephrectomy group. CONCLUSIONS/INTERPRETATION: In nephrectomised individuals, the hepatic compensatory response to acute SGLT2 inhibitor-induced glucosuria was attenuated, as compared with individuals with residual native kidneys, suggesting that SGLT2 inhibitor-mediated stimulation of hepatic glucose production via efferent renal nerves occurs in an attempt to compensate for the urinary glucose loss (i.e. a renal-hepatic axis). TRIAL REGISTRATION: ClinicalTrials.gov NCT03168295 FUNDING: This protocol was supported by Qatar National Research Fund (QNRF) Award No. NPRP 8-311-3-062 and NIH grant DK024092-38. Graphical abstract.


Assuntos
Glucose/metabolismo , Transportador 2 de Glucose-Sódio/metabolismo , Adulto , Idoso , Método Duplo-Cego , Hemoglobinas Glicadas/metabolismo , Humanos , Transplante de Rim , Pessoa de Meia-Idade , Nefrectomia
8.
Anal Bioanal Chem ; 412(25): 6909-6916, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32691087

RESUMO

The current guidelines for sweat chloride analysis identify the procedures for sweat collection, but not for chloride assay, which is usually performed by methods originally not aiming at the low concentrations of chloride found in sweat. To overcome this limitation, we set up, characterized, and adopted an original inductively coupled plasma mass spectrometry (ICP-MS) method for sweat chloride determination, which was designed for its easy use in a clinical laboratory. The method was linear in the range 8.5E-3 to 272.0E-3 mM, precision exhibited a relative standard deviation < 6%, and accuracy was in the range 99.7-103.8%. Limit of blank, limit of detection, and limit of quantitation were 2.1 mM, 3.2 mM, and 7.0 mM, respectively, which correspond to real concentrations injected into the mass spectrometer of 3.9E-3 mM for LOD and 8.5E-3 mM for LOQ. At first, the method was tested on 50 healthy volunteers who exhibited a mean chloride concentration of 15.7 mM (25-75th percentile 10.1-19.3 mM, range 2.8-37.4 mM); then, it was used to investigate two patients with suspected cystic fibrosis, who exhibited sweat chloride values of 65.6 mM and 81.2 mM, respectively. Moreover, the method was cross-validated by assaying 50 samples with chloride concentration values in the range 10-131 mM, by both ICP-MS and coulometric titration, which is the technology officially used in Tuscany for cystic fibrosis newborn screening. The reference analytical performances and the relatively low cost of ICP-MS, accompanied by the advantageous cost of a single sweat chloride assay, make this technology the best candidate to provide a top reference method for the quantification of chloride in sweat. The method that we propose was optimized and validated for sweat samples ≥ 75 mg, which is the minimum amount requested by the international protocols. However, the method sensitivity and, in addition, the possibility to reduce the sample dilution factor, make possible the quantification of chloride even in samples weighting < 75 mg that are discarded according to the current guidelines. Graphical abstract.


Assuntos
Cloretos/análise , Fibrose Cística/diagnóstico , Espectrometria de Massas/métodos , Suor/química , Adulto , Estudos de Casos e Controles , Humanos , Limite de Detecção , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
9.
Clin Chim Acta ; 508: 146-153, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32417212

RESUMO

N-acetylaspartate is a human endogenous compound synthesized by neurons, which is involved in neuronal metabolism. It is used as a marker in brain magnetic resonance spectroscopy to investigate several neurological and metabolic disorders, that can be related to a variation of its concentration with respect to reference values. N-acetylaspartate is present also in biological fluids, such as plasma, urine, and cerebrospinal fluid, where it can be quantified. Here we describe the development and validation, in compliance with the EMA guidelines, of a novel assay method for the quantification of N-acetylaspartate in plasma based on tandem mass spectrometry coupled to liquid chromatography. Its peculiarity lies in the fact that sample preparation includes an esterification step, which significantly improves the chromatographic performances and, consequently, also the method sensitivity, reproducibility and accuracy. Instrumental LLOQ is 0.06 ng/mL, i.e. at least 300 times lower than the medium N-acetylaspartate concentration in samples, accuracy is in the range 98-103%, while precision lies between 1 and 3%. The method robustness was tested in about 1000 injections of plasma samples, 96 of which were used also to assess the reference ranges in control subjects (16.46-63.40 ng/mL). Controls were then compared to plasma samples from type 2 diabetic patients. Contrary to brain magnetic resonance spectroscopy, which demonstrated a decrease in the N-acetylaspartate levels in right frontal and parieto-temporal region of type 2 diabetic patients, plasma analysis showed no statistical difference with respect to controls. However, the method here described can be profitably used in studies concerning different disorders with CNS involvement, as confirmed by reports available in the literature.


Assuntos
Espectrometria de Massas em Tandem , Ácido Aspártico/análogos & derivados , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Humanos , Reprodutibilidade dos Testes
10.
Artigo em Inglês | MEDLINE | ID: mdl-32362872

RESUMO

Background: N-acetylaspartate (NAA) is synthesized only by neurons and is involved in neuronal metabolism and axonal myelination. NAA is the strongest signal on brain magnetic resonance spectroscopy, and its concentration have been associated with cognitive dysfunction in neurodegenerative diseases, obesity, and type 2 diabetes (T2D). Materials and Methods: We explored the impact of obesity and T2D on circulating NAA as well as the impact of bariatric surgery and antidiabetic treatments. We developed an LC-MS method for the accurate measurements of fasting plasma NAA levels in 505 subjects (156 subjects with normal glucose tolerance, 24 subjects with impaired glucose tolerance, and 325 patients with T2D) to examine the associations of NAA with obesity and dysglycemia. To validate cross-sectional findings, plasma NAA was measured 6 months after Roux-en-Y Gastric Bypass (RYGB) in 55 morbidly obese subjects, and after 1 year of antidiabetic treatment (with dapagliflozin, exenatide, or dapagliflozin plus exenatide) in 192 T2D patients. Results: In the whole population, NAA was associated with age (r = 0.31, p <0.0001) and BMI (r = -0.20, p <0.0001). Independently of age and BMI, NAA was reciprocally related to HbA1c and fasting plasma glucose (partial r = -0.13, both p = 0.01). Surgically-induced weight loss raised NAA (by 18 nmol/L on average, p <0.02). Glucose lowering treatment increased NAA in proportion to the drop in HbA1c (r = 0.31, p <0.0001) regardless of the agent used. Conclusions: Circulating NAA concentrations are modulated by age, obesity, and glycemic control. Whether they may mark for the corresponding metabolic effects on brain function remains to be established by joint measurements of spectroscopic signal and cognitive function.


Assuntos
Ácido Aspártico/análogos & derivados , Cirurgia Bariátrica/métodos , Biomarcadores/sangue , Diabetes Mellitus Tipo 2/sangue , Intolerância à Glucose/sangue , Hipoglicemiantes/uso terapêutico , Obesidade Mórbida/sangue , Adulto , Idoso , Ácido Aspártico/sangue , Glicemia/análise , Estudos de Casos e Controles , Estudos Transversais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/cirurgia , Feminino , Seguimentos , Intolerância à Glucose/tratamento farmacológico , Intolerância à Glucose/cirurgia , Hemoglobinas Glicadas/análise , Humanos , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/tratamento farmacológico , Obesidade Mórbida/cirurgia , Prognóstico , Estudos Retrospectivos , Adulto Jovem
11.
Clin Chim Acta ; 493: 31-35, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30802440

RESUMO

The present paper describes the development and the validation process - in compliance with the EMA guidelines - of a method based on tandem mass spectrometry coupled to liquid chromatography for the accurate quantification of mannose in human plasma samples. The quick sample preparation procedure, simplified by the absence of any derivatization step, makes the assay suitable for routine use in a clinical chemistry laboratory. The method validation yielded satisfactory selectivity, with a good separation of mannose from its epimers (glucose and galactose), linearity over the whole concentration range of interest (0.31-40 µg/mL), reproducibility with RSD <10%, and accuracy in the range 96-104%. Instrumental LLOD (0.31 µg/mL) and LLOQ (1.25 µg/mL) were good enough to detect endogenous plasma mannose levels and in agreement with recent data from the literature. Sensitivity was affected by a 5-fold dilution factor, which, if necessary, can be reduced. The method robustness was proven in >600 injections, most of them being of plasma samples, used also to assess the reference ranges in healthy subjects (9.93 ±â€¯3.37 µg/mL) and type 2 diabetic patients (23.47 ±â€¯6.19 µg/mL).


Assuntos
Diabetes Mellitus Tipo 2/sangue , Manose/sangue , Adulto , Índice de Massa Corporal , Cromatografia Líquida de Alta Pressão , Voluntários Saudáveis , Humanos , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem
12.
Oncologist ; 24(6): 743-e205, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30591548

RESUMO

LESSONS LEARNED: The androgen receptor (AR) is present in most breast cancers (BC), but its exploitation as a therapeutic target has been limited.This study explored the activity of dehydroepiandrosterone (DHEA), a precursor being transformed into androgens within BC cells, in combination with an aromatase inhibitor (to block DHEA conversion into estrogens), in a two-stage phase II study in patients with AR-positive/estrogen receptor-positive/human epidermal growth receptor 2-negative metastatic BC.Although well tolerated, only 1 of 12 patients obtained a prolonged clinical benefit, and the study was closed after its first stage for poor activity. BACKGROUND: Androgen receptors (AR) are expressed in most breast cancers, and AR-agonists have some activity in these neoplasms. We investigated the safety and activity of the androgen precursor dehydroepiandrosterone (DHEA) in combination with an aromatase inhibitor (AI) in patients with AR-positive metastatic breast cancer (MBC). METHODS: A two-stage phase II study was conducted in two patient cohorts, one with estrogen receptor (ER)-positive (resistant to AIs) and the other with triple-negative MBC. DHEA 100 mg/day was administered orally. The combination with an AI aimed to prevent the conversion of DHEA into estrogens. The main endpoint was the clinical benefit rate. The triple-negative cohort was closed early. RESULTS: Twelve patients with ER-positive MBC were enrolled. DHEA-related adverse events, reported in four patients, included grade 2 fatigue, erythema, and transaminitis, and grade 1 drowsiness and musculoskeletal pain. Clinical benefit was observed in one patient with ER-positive disease whose tumor had AR gene amplification. There was wide inter- and intra-patient variation in serum levels of DHEA and its metabolites. CONCLUSION: DHEA showed excellent safety but poor activity in MBC. Although dose and patient selection could be improved, high serum level variability may hamper further DHEA development in this setting.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Desidroepiandrosterona/administração & dosagem , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Receptores Androgênicos/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Inibidores da Aromatase/administração & dosagem , Inibidores da Aromatase/efeitos adversos , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Desidroepiandrosterona/efeitos adversos , Progressão da Doença , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Receptores de Estrogênio/metabolismo , Critérios de Avaliação de Resposta em Tumores Sólidos , Análise de Sobrevida , Fatores de Tempo , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia
13.
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
14.
Invest New Drugs ; 34(6): 760-770, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27557783

RESUMO

The aim of the present study was to evaluate clinical activity, and the pharmacodynamic and pharmacokinetic profiles, of oral metronomic vinorelbine (VNR) plus dexamethasone (DEX) in metastatic castration-resistant prostate cancer (mCRPC) patients. Fourty-one patients (92 % chemotherapy-resistant) received 30 mg/day VNR p.o. thrice a week plus 1 mg/day DEX p.o. until disease progression. Plasma soluble B cell antigen 7 homolog 3 (sB7-H3), vascular endothelial growth factor (VEGF), and thrombospondin-1 (TSP-1), were measured by ELISA. Plasma VNR was detected using a LC-MS-MS system. The fraction of patients free of progression, defined by criteria of the Prostate Cancer Clinical Trials Working Group 2, at 3 months was 61 %. PSA decrease ≥50 % from baseline was observed in 35 % of patients. Median PFS and OS were 4 months (95 % CI, 2.8-6.9) and 17.5 months (95 % CI, 10.8-24.5), respectively. Toxicity was mild, and no grade 4 toxicities were found. The mean plasma VNR Cmax ranged from 1 to 2.7 ng/ml (Tmax 1.1 h) and no evidence of drug accumulation was found. A moderate relationship was found between plasma sB7-H3 and PSA values (r = 0.565; P = 0.0094) at the baseline. Increased PFS (11.3 vs. 2.8 months; P = 0.0298) was observed in patients with sB7-H3 levels <30.25 ng/mL. Plasma VEGF AUC0-24day increased in non-responders (P < 0.0001), whereas responders maintained higher plasma TSP-1 AUC0-24day (P = 0.0063). In conclusion, metronomic VNR plus DEX showed favourable activity, and a low toxicity profile, in mCRPC patients. Plasma sB7-H3, VEGF and TSP-1 levels are potential pharmacodynamic markers at the reached low plasma concentrations of vinorelbine metronomically administered.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Neoplasias Ósseas/secundário , Dexametasona/administração & dosagem , Seguimentos , Humanos , Neoplasias Pulmonares/secundário , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Neoplasias de Próstata Resistentes à Castração/patologia , Taxa de Sobrevida , Distribuição Tecidual , Vimblastina/administração & dosagem , Vimblastina/análogos & derivados , Vinorelbina
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