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1.
Hum Reprod ; 39(5): 1078-1088, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38503490

RESUMO

STUDY QUESTION: Is resumption of ovulation after a 6-month lifestyle intervention in women with PCOS and obesity associated with differential changes in endocrine and metabolic parameters (weight, insulin resistance, anti-Müllerian hormone (AMH), and androgens) compared to women with PCOS who remained anovulatory? SUMMARY ANSWER: Resumption of ovulation after a 6-month lifestyle intervention in women with PCOS and obesity is associated with changes in serum 11ß-hydroxyandrostenedione (11OHA4) concentrations. WHAT IS KNOWN ALREADY: Lifestyle interventions have been shown to reduce clinical and biochemical hyperandrogenism in women with PCOS. Weight loss of 5-10% may reverse anovulatory status, thereby increasing natural conception rates. However, the mechanisms underlying why some women with PCOS remain anovulatory and others resume ovulation after weight loss are unclear. Reproductive characteristics at baseline and a greater degree of change in endocrine and metabolic features with lifestyle intervention may be crucial for ovulatory response. STUDY DESIGN, SIZE, DURATION: We used data and samples originating from an earlier randomized controlled trial (RCT), which examined the efficacy of a 6-month lifestyle intervention prior to infertility treatment compared to prompt infertility treatment on live birth rate in women with obesity. A total of 577 women with obesity (BMI > 29 kg/m2) were randomized between 2009 and 2012. Anovulatory women with PCOS who were allocated to the intervention arm of the original RCT (n = 95) were included in the current analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS: We defined women as having resumed ovulation (RO+) based on the following criteria: spontaneous pregnancy; or assignment to expectant management; or IUI in natural cycles as the treatment strategy after lifestyle intervention. Steroid hormones were measured using liquid chromatography tandem mass spectrometry. Generalized estimating equations with adjustment for baseline measures and interaction between group and time was used to examine differences in changes of endocrine and metabolic parameters between RO+ (n = 34) and persistently anovulatory women (RO-, n = 61) at 3 and 6 months after intervention. MAIN RESULTS AND THE ROLE OF CHANCE: At baseline, the mean ± SD age was 27.5 ± 3.6 years in the RO+ group and 27.9 ± 4.1 years in the RO- group (P = 0.65), and the mean ± SD weights were 101.2 ± 9.5 kg and 105.0 ± 14.6 kg, respectively (P = 0.13). Baseline AMH concentrations showed significant differences between RO+ and RO- women (median and interquartile range [IQR] 4.7 [3.2; 8.3] versus 7.2 [5.3; 10.8] ng/ml, respectively). Baseline androgen concentrations did not differ between the two groups. During and after lifestyle intervention, both groups showed weight loss; changes in 11OHA4 were significantly different between the RO+ and RO groups (P-value for interaction = 0.03). There was a similar trend for SHBG (interaction P-value = 0.07), and DHEA-S (interaction P-value = 0.06), with the most pronounced differences observed in the first 3 months. Other parameters, such as AMH and FAI, decreased over time but with no difference between the groups. LIMITATIONS, REASONS FOR CAUTION: No high-resolution transvaginal ultrasonography was used to confirm ovulatory status at the end of the lifestyle program. The small sample size may limit the robustness of the results. WIDER IMPLICATIONS OF THE FINDINGS: Reduction of androgen concentrations during and after lifestyle intervention is associated with recovery of ovulatory cycles. If our results are confirmed in other studies, androgen concentrations could be monitored during lifestyle intervention to provide individualized recommendations on the timing of resumption of ovulation in anovulatory women with PCOS and obesity. STUDY FUNDING/COMPETING INTEREST(S): The study was supported by a grant from ZonMw, the Dutch Organization for Health Research and Development (50-50110-96-518). The Department of Obstetrics and Gynecology of the UMCG received an unrestricted educational grant from Ferring Pharmaceuticals BV, The Netherlands. A.H. reports consultancy for the development and implementation of a lifestyle App MyFertiCoach developed by Ferring Pharmaceutical Company. All other authors have no conflicts to declare. TRIAL REGISTRATION NUMBER: The LIFEstyle RCT was registered at the Dutch trial registry (NTR 1530).


Assuntos
Anovulação , Obesidade , Ovulação , Síndrome do Ovário Policístico , Humanos , Feminino , Obesidade/complicações , Obesidade/terapia , Adulto , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/terapia , Androstenodiona/sangue , Resistência à Insulina , Gravidez , Hormônio Antimülleriano/sangue , Redução de Peso
2.
Int J Cardiol Heart Vasc ; 34: 100798, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34095450

RESUMO

INTRODUCTION: The importance of gut microbiome in cardiovascular disease has been increasingly recognized. Trimethylamine N-oxide (TMAO) is a gut microbe-derived metabolite that is associated with cardiovascular disease, including atrial fibrillation (AF). The role of TMAO in clinical AF progression however remains unknown. METHODS AND RESULTS: In this study we measured TMAO and its precursor (betaine, choline, and L- carnitine) levels in 78 patients using plasma samples from patients that participated in the AF-RISK study. 56 patients suffered from paroxysmal AF and 22 had a short history of persistent AF. TMAO levels were significantly higher in patients with persistent AF, as compared to those with paroxysmal AF (median [IQR] 5.65 [4.7-9.6] m/z versus 4.31 [3.2-6.2] m/z, p < 0.05), while precursor levels did not differ. In univariate analysis, we observed that for every unit increase in TMAO, the odds for having persistent AF increased with 0.44 [0.14-0.73], p < 0.01. Conclusion: These results suggest that higher levels of TMAO are associated with more progressed forms of AF. We therefore hypothesize that increased TMAO levels may reflect disease progression in humans. Larger studies are required to validate these preliminary findings.Trial Registration number: Clinicaltrials.gov NCT01510210.

3.
J Pharmacol Exp Ther ; 374(1): 62-73, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32269169

RESUMO

Arginase is a potential target for asthma treatment. However, there are currently no arginase inhibitors available for clinical use. Here, a novel class of arginase inhibitors was synthesized, and their efficacy was pharmacologically evaluated. The reference compound 2(S)-amino-6-boronohexanoic acid (ABH) and >200 novel arginase inhibitors were tested for their ability to inhibit recombinant human arginase 1 and 2 in vitro. The most promising compounds were separated as enantiomers. Enantiomer pairs SHK242 and SHK243, and SHK277 and SHK278 were tested for functional efficacy by measuring their effect on allergen-induced airway narrowing in lung slices of ovalbumin-sensitized guinea pigs ex vivo. A guinea pig model of acute allergic asthma was used to examine the effect of the most efficacious enantiopure arginase inhibitors on allergen-induced airway hyper-responsiveness (AHR), early and late asthmatic reactions (EAR and LAR), and airway inflammation in vivo. The novel compounds were efficacious in inhibiting arginase 1 and 2 in vitro. The enantiopure SHK242 and SHK277 fully inhibited arginase activity, with IC50 values of 3.4 and 10.5 µM for arginase 1 and 2.9 and 4.0 µM for arginase 2, respectively. Treatment of slices with ABH or novel compounds resulted in decreased ovalbumin-induced airway narrowing compared with control, explained by increased local nitric oxide production in the airway. In vivo, ABH, SHK242, and SHK277 protected against allergen-induced EAR and LAR but not against AHR or lung inflammation. We have identified promising novel arginase inhibitors for the potential treatment of allergic asthma that were able to protect against allergen-induced early and late asthmatic reactions. SIGNIFICANCE STATEMENT: Arginase is a potential drug target for asthma treatment, but currently there are no arginase inhibitors available for clinical use. We have identified promising novel arginase inhibitors for the potential treatment of allergic asthma that were able to protect against allergen-induced early and late asthmatic reactions. Our new inhibitors show protective effects in reducing airway narrowing in response to allergens and reductions in the early and late asthmatic response.


Assuntos
Alérgenos/efeitos adversos , Arginase/antagonistas & inibidores , Asma/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Animais , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/uso terapêutico , Cobaias , Masculino
4.
Int J Tryptophan Res ; 13: 1178646920972657, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33447045

RESUMO

Alzheimer's disease (AD) is associated with progressive endogenous neurotoxicity and hampered inflammatory regulation. The kynurenine (Kyn) pathway, which is controlled by tryptophan 2,3-dioxygenase (TDO), produces neuroactive and anti-inflammatory metabolites. Age-related Kyn pathway activation might contribute to AD pathology in humans, and inhibition of TDO was found to reduce AD-related cellular toxicity and behavioral deficits in animal models. To further explore the effect of aging on the Kyn pathway in the context of AD, we analyzed Kyn metabolite profiles in serum and brain tissue of the APP23 amyloidosis mouse model. We found that aging had genotype-independent effects on Kyn metabolite profiles in serum, cortex, hippocampus and cerebellum, whereas serum concentrations of many Kyn metabolites were reduced in APP23 mice. Next, to further establish the role of TDO in AD-related behavioral deficits, we investigated the effect of long-term pharmacological TDO inhibition on cognitive performance in APP23 mice. Our results indicated that TDO inhibition reversed recognition memory deficits without producing measurable changes in cerebral Kyn metabolites. TDO inhibition did not affect spatial learning and memory or anxiety-related behavior. These data indicate that age-related Kyn pathway activation is not specific for humans and could represent a cross-species phenotype of aging. These data warrant further investigation on the role of peripheral Kyn pathway disturbances and cerebral TDO activity in AD pathophysiology.

5.
Psychoneuroendocrinology ; 88: 78-91, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29195161

RESUMO

After decades of research, the influence of prenatal testosterone on brain lateralization is still elusive, whereas the influence of pubertal testosterone on functional brain lateralization has not been investigated, although there is increasing evidence that testosterone affects the brain in puberty. We performed a longitudinal study, investigating the relationship between prenatal testosterone concentrations in amniotic fluid, pubertal testosterone concentrations in saliva, and brain lateralization (measured with functional Transcranial Doppler ultrasonography (fTCD)) of the Mental Rotation, Chimeric Faces and Word Generation tasks. Thirty boys and 30 girls participated in this study at the age of 15 years. For boys, we found a significant interaction effect between prenatal and pubertal testosterone on lateralization of Mental Rotation and Chimeric Faces. In the boys with low prenatal testosterone levels, pubertal testosterone was positively related to the strength of lateralization in the right hemisphere, while in the boys with high prenatal testosterone levels, pubertal testosterone was negatively related to the strength of lateralization. For Word Generation, pubertal testosterone was negatively related to the strength of lateralization in the left hemisphere in boys. For girls, we did not find any significant effects, possibly because their pubertal testosterone levels were in many cases below quantification limit. To conclude, prenatal and pubertal testosterone affect lateralization in a task-specific way. Our findings cannot be explained by simple models of prenatal testosterone affecting brain lateralization in a similar way for all tasks. We discuss alternative models involving age dependent effects of testosterone, with a role for androgen receptor distribution and efficiency.


Assuntos
Lateralidade Funcional/efeitos dos fármacos , Lateralidade Funcional/fisiologia , Testosterona/fisiologia , Adolescente , Encéfalo/fisiopatologia , Cognição/fisiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Puberdade/metabolismo , Receptores Androgênicos , Caracteres Sexuais , Maturidade Sexual , Testosterona/metabolismo , Ultrassonografia Doppler Transcraniana/métodos
6.
Neurosci Biobehav Rev ; 65: 264-75, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27073048

RESUMO

Dystonia is a hyperkinetic movement disorder characterized by sustained or intermittent muscle contractions. Emerging data describe high prevalences of non-motor symptoms, including psychiatric co-morbidity, as part of the phenotype of dystonia. Basal ganglia serotonin and serotonin-dopamine interactions gain attention, as imbalances are known to be involved in extrapyramidal movement and psychiatric disorders. We systematically reviewed the literature for human and animal studies relating to serotonin and its role in dystonia. An association between dystonia and the serotonergic system was reported with decreased levels of 5-hydroxyindolacetic acid, the main metabolite of serotonin. A relation between dystonia and drugs affecting the serotonergic system was described in 89 cases in 49 papers. Psychiatric co-morbidity was frequently described, but likely underestimated as it was not systematically examined. Currently, there are no good (pharmaco)therapeutic options for most forms of dystonia or associated non-motor symptoms. Further research using selective serotonergic drugs in appropriate models of dystonia is required to establish the role of the serotonergic system in dystonia and to guide us to new therapeutic strategies.


Assuntos
Distúrbios Distônicos , Animais , Gânglios da Base , Humanos , Transtornos Mentais , Serotoninérgicos
7.
J Chem Phys ; 121(21): 10707-14, 2004 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-15549956

RESUMO

We study the pi*<--pi singlet excitations of the pi-conjugated oligomers of polyacetylene, polydiacetylene, polybutatriene, polythiophene, poly(para-phenylene vinylene), and the lowest singlet excitations of the hydrogen chain. For this we used time-dependent current-density-functional theory within the Vignale-Kohn and adiabatic local density approximations. By studying the dependence of the excitation spectrum on the chain length we conclude that the reduction of the static polarizability when using the Vignale-Kohn functional has two origins. First, the excitation energies of transitions with a large transition dipole are shifted upward. Second, the character of the transition between the lowest occupied and highest unoccupied molecular orbitals and the oscillator strength of the lowest transition within the adiabatic local density approximation is transferred to higher transitions. The lowest transitions that have a considerable oscillator strength obtained with the Vignale-Kohn functional have excitation energies that are in most cases in better agreement with available reference data than the adiabatic local density approximation.

8.
J Chem Phys ; 120(18): 8353-63, 2004 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-15267758

RESUMO

In this article we explain how the existing linear response theory of time-dependent density-functional theory can be extended to obtain excitation energies in the framework of time-dependent current-density-functional theory. We use the Vignale-Kohn current-functional [G. Vignale and W. Kohn, Phys. Rev. Lett. 77, 2037 (1996)] which has proven to be successful for describing ultranonlocal exchange-correlation effects in the case of the axial polarizability of molecular chains [M. van Faassen, P. L. de Boeij, R. van Leeuwen, J. A. Berger, and J. G. Snijders, Phys. Rev. Lett. 88, 186401 (2002); J. Chem. Phys. 118, 1044 (2003)]. We study a variety of singlet excitations for a benchmark set of molecules. The pi(*)<--pi transitions obtained with the Vignale-Kohn functional are in good agreement with experiment and other theoretical results and they are in general an improvement upon the adiabatic local density approximation. In case of the pi(*)<--n transitions the Vignale-Kohn functional fails, giving results that strongly overestimate the experimental and other theoretical results. The benchmark set also contains some other types of excitations for which no clear failures or improvements are observed.

9.
Phys Rev Lett ; 88(18): 186401, 2002 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-12005703

RESUMO

We solve the long-standing problem of the large overestimation of the static polarizability of conjugated polymers obtained using the local density approximation within density-functional theory. The local approximation is unable to describe the highly nonlocal exchange and correlation (xc) effects found in these quasi-one-dimensional systems. Time-dependent current-density-functional theory enables a local current description of ultranonlocal xc effects using the Vignale-Kohn functional [G. Vignale and W. Kohn, Phys. Rev. Lett. 77, 2037 (1996)]. Except for the model hydrogen chain, our results are in excellent agreement with the best available correlated methods.

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