Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
J Endocrinol Invest ; 46(7): 1333-1341, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36705838

RESUMO

PURPOSE: The contraceptive gestodene is a potent synthetic progestin used in several low-dose contraceptive formulations. Clinical studies reported a relationship between long-term use of combined oral contraceptives containing gestodene (GDN) and profound alterations in glucose metabolism in women. The observation that contraceptive synthetic progestins exert hormone-like effects other than their progestational activities, prompted us to investigate whether GDN may induce estrogen-like effects, even though GDN does not interact with estrogen receptors. The aim of this study was to investigate whether GDN affect pancreatic ß-cell activity, directly or through its conversion to other bioactive metabolites. METHODS: The effects of GDN and its two derivatives 3ß,5α-tetrahydro-GDN and 3α,5α-tetrahydro-GDN on insulin 2 (Ins II) and glucokinase (Gk) expression and glucose-stimulated insulin secretion were determined in pancreatic islets from female rats. RESULTS: Gestodene did exert significant effects on islet ß-cells activity. The most striking finding was that 3ß,5α-tetrahydro-GDN and 3α,5α-tetrahydro-GDN had greater stimulatory effects on Ins II and Gk expression than that observed with GDN, consistent with their effects on glucose-stimulated insulin secretion. The effects on gene expression induced by GDN-derivatives were abolished by ICI 182,780 and MPP. In addition, the presence of inhibitors of androgen and progestin-metabolizing enzymes eliminated gene expression induced by GDN. These results indicated that GDN is metabolized to A-ring reduced metabolites with estrogen-like activities and through this mechanism, GDN may affect ß-cell activity. CONCLUSIONS: Altogether, the data suggest that 19-nortestosterone-derived contraceptives such as GDN, possess insulinotropic effects through their conversion into metabolites with intrinsic estrogen-like activity in pancreatic ß-cells.


Assuntos
Estrogênios , Norpregnenos , Humanos , Feminino , Ratos , Animais , Norpregnenos/metabolismo , Norpregnenos/farmacologia , Anticoncepcionais Orais Combinados , Congêneres da Progesterona/metabolismo , Congêneres da Progesterona/farmacologia , Glucose
2.
J Endocrinol Invest ; 44(9): 1897-1904, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33486704

RESUMO

BACKGROUND: High-density lipoprotein (HDL) is considered a complex plasma-circulating particle with subfractions that vary in function, size, and chemical composition. We sought to test the effects of HDL, and HDL subfractions on insulin secretion and cholesterol efflux in the ß-cell line MIN-6. METHODS: We used total HDL and HDL subfractions 2a, 2b, 3a, 3b, and 3c, isolated from human plasma, to test insulin secretion under different glucose concentrations as well as insulin content and cholesterol efflux in the insulinoma MIN-6 cell line. RESULTS: Incubation of MIN-6 cells with low glucose and total HDL increased insulin release two-fold. Meanwhile, when high glucose and HDL were used, insulin release increased more than five times. HDL subfractions 2a, 2b, 3a, 3b, and 3c elicited higher insulin secretion and cholesterol efflux than their respective controls, at both low and high glucose concentrations. The insulin content of the MIN-6 cells incubated with low glucose and any of the five HDL subclasses had a modest reduction compared with their controls. However, there were no statistically significant differences between each HDL subfraction on their capacity of eliciting insulin secretion, insulin content, or cholesterol efflux. CONCLUSIONS: HDL can trigger insulin secretion under low, normal, and high glucose conditions. We found that all HDL subfractions exhibit very similar capacity to increase insulin secretion and cholesterol efflux. This is the first report demonstrating that HDL subfractions act both as insulin secretagogues (under low glucose) and insulin secretion enhancers (under high glucose) in the MIN-6 cell line.


Assuntos
Colesterol/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Lipoproteínas HDL/sangue , Adulto , Animais , Linhagem Celular Tumoral , Feminino , Glucose/farmacologia , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade
3.
J Endocrinol Invest ; 43(8): 1061-1071, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32016916

RESUMO

PURPOSE: Type 2 diabetes (T2D) and low serum concentration of high-density lipoprotein cholesterol (HDL-c) are common coexisting metabolic disorders. ABCA1 variants have been shown to be associated to these conditions. We sought to test the combined effect of two ABCA1 gene common variants, rs2422493 (- 565C > T) and rs9282541 (R230C) on HDL-c levels and T2D risk. METHODS: Path analysis was conducted in 3,303 Mexican-mestizos to assess the specific contributions of rs2422493 and rs9282541 ABCA1 variants, insulin resistance, waist-to-height ratio (WHtR), and age on HDL-c levels and T2D risk. Participants were classified into four groups according to their ABCA1 variants carrier status: (i) the reference group carried wild type alleles for both ABCA1 variants (-/-), (ii) +/- were carriers of rs2422493 but non-carriers of rs9282541, (iii) -/+ for carriers of rs9282541 but not carriers of rs2422493 and (iv) carriers of minor alleles for both SNPs (+/+). Principal components from two previous genome-wide association studies were used to control for ethnicity. RESULTS: We identified significant indirect effects on T2D risk mediated by HDL-c in groups -/+ and +/+ (ß = 0.04; p = 0.03 and ß = 0.06; p < 0.01, respectively) in comparison to the -/- reference group. Low concentrations of HDL-c were directly and significantly associated with increased T2D risk (ß = -0.70; p < 0.01). WHtR, male gender, age, and insulin resistance were also associated with T2D risk (p < 0.05). There was no significant direct effect for any of the ABCA1 groups on T2D risk: p = 0.99, p = 0.58, and p = 0.91 for groups +/-, -/+, and +/+ respectively. CONCLUSIONS: The ABCA1 rs9282541 (R230C) allele is associated with T2D in Mexicans through its effect on lowering HDL-c levels. This is the first report demonstrating that HDL-c levels act as an intermediate factor between an ABCA1 variant and T2D.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/genética , HDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Adulto , Biomarcadores/análise , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/genética , Feminino , Seguimentos , Estudo de Associação Genômica Ampla , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Prognóstico
4.
Int J Endocrinol ; 2015: 149408, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26491436

RESUMO

Prevalence of metabolic syndrome and progression of nephropathy depend on sex. We examined a protective effect of estradiol against nephropathy in metabolic syndrome through the modulation of the arachidonic acid metabolism by activating the 5-lipoxygenase and cytochrome p450 4A pathways. 28 female Wistar rats were divided into four groups of seven animals each: control, intact metabolic syndrome, ovariectomized metabolic syndrome, and metabolic syndrome ovariectomized plus estradiol. Blood pressure, body weight, body fat, triglycerides, insulin, HOMA-index, albuminuria, and TNF-α were increased in ovariectomized metabolic syndrome rats (p < 0.001). The perfusion pressure in isolated kidneys of ovariectomized metabolic syndrome rats in presence of 4 µg of arachidonic acid was increased. The inhibitors of the arachidonic acid metabolism Baicalein, Miconazole, and Indomethacin in these rats decreased the perfusion pressure by 57.62%, 99.83%, and 108.5%, respectively and they decreased creatinine clearance and the arachidonic acid percentage. Phospholipase A2 expression in the kidney of ovariectomized metabolic syndrome rats was not modified. 5-lipoxygenase was increased in metabolic syndrome ovariectomized rats while cytochrome p450 4A was decreased. In conclusion, the loss of estradiol increases renal damage while the treatment with estradiol benefits renal function by modulating arachidonic acid metabolism through the 5-lipoxygenase and cytochrome p450 4A pathways.

5.
Peptides ; 57: 101-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24819472

RESUMO

Renin-Angiotensin System (RAS) plays an important role in the development of Metabolic Syndrome (MS) and in aging. Angiotensin 1-7 (Ang 1-7) has opposite effects to Ang II. All of the components of RAS are expressed locally in adipose tissue and there is over-activation of adipose RAS in obesity and hypertension. We determined serum and abdominal adipose tissue Ang II and Ang 1-7 in control and MS rats during aging and the expression of AT1, AT2 and Mas in white adipose tissue. MS was induced by sucrose ingestion during 6, 12 and 18 months. During aging, an increase in body weight, abdominal fat and dyslipidemia were found but increases in aging MS rats were higher. Control and MS concentrations of serum Ang II from 6-month old rats were similar. Aging did not modify Ang II seric concentration in control rats but decreased it in MS rats. Ang II levels increased in WAT from both groups of rats. Serum and adipose tissue Ang 1-7 increased during aging in MS rats. Western blot analysis revealed that AT1 expression increased in the control group during aging while AT2 and Mas remained unchanged. In MS rats, AT1 and AT2 expression decreased significantly in aged rats. The high concentration of Ang 1-7 and adiponectin in old MS rats might be associated to an increased expression of PPAR-γ. PPAR-γ was increased in adipose tissue from MS rats. It decreased with aging in control rats and showed no changes during aging in MS rats. Ang 1-7/Mas axis was the predominant pathway in WAT from old MS animals and could represent a potential target for therapeutical strategies in the treatment of MS during aging.


Assuntos
Angiotensina II/metabolismo , Angiotensina I/metabolismo , Síndrome Metabólica/genética , Fragmentos de Peptídeos/metabolismo , Proteínas Proto-Oncogênicas/biossíntese , Receptor Tipo 2 de Angiotensina/biossíntese , Receptores de Angiotensina/biossíntese , Receptores Acoplados a Proteínas G/biossíntese , Tecido Adiposo Branco/metabolismo , Envelhecimento/genética , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Regulação da Expressão Gênica , Humanos , Hipertensão/genética , Hipertensão/patologia , Síndrome Metabólica/metabolismo , Síndrome Metabólica/patologia , Proto-Oncogene Mas , Ratos , Sistema Renina-Angiotensina/genética
6.
J Dev Orig Health Dis ; 3(6): 483-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25084301

RESUMO

Diabetes predisposition is determined by pancreatic islet insulin secretion and insulin resistance. We studied female rat offspring exposed to low-protein maternal diet (50% control protein diet) in pregnancy and/or lactation at postnatal days 36, 110 and 450. Rats were fed either control 20% casein diet (C) or restricted diet (R - 10% casein) during pregnancy. After delivery, mothers received either C or R diet until weaning to provide four offspring groups: CC, RR, CR and RC (first letter denoting maternal pregnancy diet and the second lactation diet). Serum glucose, insulin and homeostatic model assessment (HOMA) were measured. Pancreatic islets were isolated and in vitro insulin secretion quantified in low glucose (5 mM) and high glucose (11 mM). Serum glucose, insulin and HOMA were similar in all groups at 36 and 110 postnatal days. HOMA was only higher in RR at 450 postnatal days. Only CC demonstrated differences in glucose sensitivity of ß-cells to high and low doses at the three ages studied. At 36 days, RR, CR and RC and at 450 days RR and RC groups did not show glucose-stimulated insulin secretion differences between low and high glucose. Aging-associated glucose-stimulated insulin secretion loss was affected by maternal dietary history, indicating that developmental programming must be considered a major factor in aging-related development of predisposition to later-life dysfunctional insulin metabolism. Female offspring islets' insulin secretion was higher than previously reported in males.


Assuntos
Envelhecimento/metabolismo , Dieta com Restrição de Proteínas , Desenvolvimento Fetal , Glucose/farmacologia , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Lactação/metabolismo , Fatores Etários , Animais , Glicemia/análise , Feminino , Secreção de Insulina , Masculino , Gravidez , Ratos , Ratos Wistar , Caracteres Sexuais
7.
Rev. esp. pediatr. (Ed. impr.) ; 61(2): 148-150, mar.-abr. 2005. tab
Artigo em Espanhol | IBECS | ID: ibc-121905

RESUMO

El tortícolis paroxístico benigno es un trastorno autolimitado que debuta en los primeros meses de vida y desaparece hacia los 5 años con preferencia por el sexo femenino. Se caracteriza por episodios de inclinación lateral de la cabeza que puede o no acompañarse de otros síntomas. Su diagnóstico es eminentemente clínico, no obstante, con el fin de descartar otras entidades, se realizan pruebas complementarias. En la actualidad existen múltiples hipótesis etiológicas del origen de este trastorno. No existe tratamiento efectivo para ella. Presentamos el caso de una niña con episodios recurrentes de inclinación lateral de la cabeza desde los 5 meses y clínica típica acompañante (AU)


Benign paroxismal torticollis is a self-limited disorder characterized by recurrent episodes of head till. Attacks can be accompanied by different symptoms. Episodes begin within the first months of life and resolve by 5 years mainly in females. The diagnosis should be established clinically, but in some cases it is necessary to rule out other condition with neuroimaging. It exist different etyomology hypothesis. There isn´t effective therapy. We report one child with recurrent episodes of head till and accompained clinic (AU)


Assuntos
Humanos , Feminino , Lactente , Torcicolo/diagnóstico , Decúbito Inclinado com Rebaixamento da Cabeça , Diagnóstico Diferencial
8.
Pediatr Cardiol ; 16(1): 42-4, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7753703

RESUMO

A 6-month-old male infant with coexistent type B interrupted aortic arch, distal aortopulmonary window, and anomalous origin of the right pulmonary artery arising from the ascending aorta was diagnosed by two-dimensional echocardiography, color Doppler, and cardiac catheterization. Review of the available literature reveals this patient to be the fourteenth reported case of this unusual association of cardiovascular defects.


Assuntos
Ecocardiografia Doppler em Cores , Ecocardiografia , Cardiopatias Congênitas/diagnóstico por imagem , Humanos , Lactente , Masculino , Síndrome
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...