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1.
Exp Eye Res ; 241: 109838, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395213

RESUMO

Limbal niche cells (LNCs) are one of the most important supporting cells for corneal epithelial stem cells (CES), however, research on LNCs has been mostly limited to humans and rats previously. To expand the research work into the rabbit animal model, one of the most often used animals in stem cell study, this study was carried out for the in vitro isolation and identification of rabbit LNCs. Rabbit LNCs were isolated by collagenase A digestion method and single cells were obtained, the cells were then seeded on 5% Matrigel-coated plastic surface and cultured in modified embryonic stem cell medium (MESCM). Three biological replicates of the isolating and characterization were recorded from New Zealand White rabbits aged from 2.5 months to 5 months. LNC markers (VIM/CD90/CD105/SCF/PDGFRß) were analyzed using tyramide signal amplification (TSA) staining, immunohistochemical staining (IHC), western blotting (WB), and real-time reverse transcription polymerase chain reaction (qPCR). TSA staining suggested that VIM was highly expressed in rabbit limbus stroma, which was confirmed by WB, and P63α was expressed in the basal limbus epithelium. Pan-CK and CK12 were highly expressed in the central corneal epithelium but lightly expressed in the limbal epithelium. The WB result indicated that PDGFRß and VIM expressions in rabbit-LNCs P4 were higher than in P1 and P7. In addition, rabbit corneal epithelium highly expressed Paired Box 6 (PAX6) and Epidermal growth factor-like domain 6(EGFL6). For the three repeat experiments, the cell expansion activity of rabbit-LNC was highest at P4. Rabbit-LNCs were passaged from P0 to P7, and the number of cell doublings (NCD) of P4 for the three repeat experiments was 2.816, 2.737, and 2.849. qPCR showed that high mRNA expression levels of VIM, CD90, CD105, SCF, and PDGFRß in rabbit-LNCs P4. In conclusion, rabbit-LNCs could be successfully isolated by the collagenase A digestion method as used in human tissue. There were similar characteristics between rabbit and human LNCs (VIM+/CD90+/CD105+/SCF+/PAX6+/PDGFRß+).


Assuntos
Epitélio Corneano , Limbo da Córnea , Coelhos , Ratos , Humanos , Animais , Células-Tronco , Córnea , Células Cultivadas , Colagenases , Células Epiteliais , Nicho de Células-Tronco
2.
FASEB J ; 36(3): e22193, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35201635

RESUMO

Infertility is a social and medical problem around the world and the incidence continues to rise. Thin endometrium (TE) is a great challenge of infertility treatment, even by in vitro fertilization and embryo transfer. It is widely believed that TE impairs endometrium receptivity. However, only a few studies have explained the molecular mechanism. Herein, in order to reveal the possible mechanism, we sampled endometrium from a TE patient and a control volunteer and got a transcriptomic atlas of 18 775 individual cells which was constructed using single-cell RNA sequencing, and seven cell types have been identified. The cells were acquired during proliferative and secretory phases, respectively. The proportion of epithelial cells and stromal cells showed a significant difference between the TE group and the control group. In addition, differential expressed genes (DEGs) in diverse cell types were revealed, the enriched pathways of DEGs were found closely related to the protein synthesis in TE of both proliferative and secretory phases. Some DEGs can influence cell-type ratio and impaired endometrial receptivity in TE. Furthermore, divergent expression of estrogen receptors 1 and progesterone receptors in stromal and epithelial cells were compared in the TE sample from the control. The cellular and molecular heterogeneity found in this study provided valuable information for disclosing the mechanisms of impaired receptivity in TE.


Assuntos
Endométrio/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Análise de Célula Única/métodos , Transcriptoma , Doenças Uterinas/metabolismo , Doenças Uterinas/patologia , Adulto , Estudos de Casos e Controles , Endométrio/efeitos dos fármacos , Estradiol/farmacologia , Estrogênios/farmacologia , Feminino , Humanos , Progesterona/farmacologia , Progestinas/farmacologia , Doenças Uterinas/tratamento farmacológico , Doenças Uterinas/genética
3.
J Obstet Gynaecol Res ; 49(4): 1173-1179, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36772863

RESUMO

OBJECTIVE: Redistribution of adipose tissue in the abdomen during the menopausal transition is attributable mostly to estrogen drop with aging. Adipose differentiation-related protein (ADRP), a major component of lipid droplets, is closely related to the onset of lipid accumulation. We hypothesized that estrogen exerted its tissue-specific effect in reducing abdominal fat accumulation by regulation of ADRP. METHODS: Twenty-four female C57/BL6 mice aged 8 weeks were randomly divided into 3 groups: sham operation (Sham), bilateral ovariectomy (OVX), and OVX plus 17ß-estradiol (OVX + E2). After being fed 8 weeks of a high-fat diet, plasma lipid profiles including total cholesterol (TC), total triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) levels, body weight gain, visceral, and subcutaneous adipose tissue, adipocyte size, and ADRP expression were measured. RESULTS: In comparison to sham-operated mice, OVX mice presented a weight gain with higher plasma TC, TG, LDL-C levels, and lower HDL-C levels. E2 supplement ameliorated the increase in weight and lipid profiles. Elevated ADRP expression was observed in visceral adipose tissue of OVX mice, whereas treatment of estrogen suppressed the ADPR expression and reversed the fat accumulation in the abdomen. However, no significant difference of ADRP expression in subcutaneous adipose tissue was detected between sham, OVX, and OVX + E2 mice. CONCLUSIONS: Our findings suggested that enhanced ADRP expression in ovariectomized mice correlates with the tissue-specific regulation of estrogen, which may provide useful clues for further exploring the regulatory mechanism and corresponding anti-abdominal obesity treatment in postmenopausal women.


Assuntos
Estrogênios , Obesidade , Camundongos , Feminino , Animais , Humanos , Perilipina-2 , LDL-Colesterol , Estrogênios/farmacologia , Estradiol/farmacologia , Triglicerídeos , Ovariectomia
4.
J Ultrasound Med ; 41(1): 41-50, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33656184

RESUMO

OBJECTIVES: The purpose of this study was to evaluate the diagnostic efficacy of transvaginal two-dimensional fundamental sonosalpingography (2D-FS) combined with saline infusion pelvic sonosalpingography (SIPS) for assessing fimbrial part's morphology and function of the fallopian tubes. METHODS: One hundred and sixty-nine cases underwent 2D-FS combined with SIPS. Among them, 18 cases received laparoscopy and dye test (LDT) within 3 months after the examination and the results were regarded as reference standard. RESULTS: Excluding proximal or middle segment obstructed tubes, the remaining fimbrial parts' display rate by using 2D-FS combined with SIPS was 75.1%. According to the ultrasonic appearance, the fimbrial parts were classified into 4 types: normal, abnormal, suspected abnormal, and unclassifiable. Normal fimbrial parts accounted for 73.8% when the tubes were patent; abnormal fimbrial parts accounted for 74.1% when the tubes were partial obstructed; all became abnormal when the tubes were distal complete obstructed. The fimbrial parts which had been classified by 2D-FS combined with SIPS were compared with LDT further. This combination's accuracy (ACC), sensitivity (SEN), specificity (SPE), positive predictive value (PPV), negative predictive value (NPV), and Youden's index (YI) were 86.4, 87.5, 85.7, 77.8, 92.3, and 0.73%, respectively. The result of consistency analysis showed the combination was essentially consistent with LDT result (Kappa = 0.713). CONCLUSION: 2D-FS combined with SIPS can be a preferred method for assessment of the fimbrial part's morphology and function, with its advantages of non-invasive, intuition, and accuracy. This combination could provide an objective imaging basis for choosing clinical treatment strategies and predicting prognosis.


Assuntos
Tubas Uterinas , Laparoscopia , Tubas Uterinas/diagnóstico por imagem , Feminino , Humanos , Histerossalpingografia , Pelve
5.
Ther Adv Endocrinol Metab ; 14: 20420188231199359, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37719789

RESUMO

Estrogen plays a prominent role in regulating and coordinating energy homeostasis throughout the growth, development, reproduction, and aging of women. Estrogen receptors (ERs) are widely expressed in the brain and nearly all tissues of the body. Within the brain, central estrogen via ER regulates appetite and energy expenditure and maintains cell glucose metabolism, including glucose transport, aerobic glycolysis, and mitochondrial function. In the whole body, estrogen has shown beneficial effects on weight control, fat distribution, glucose and insulin resistance, and adipokine secretion. As demonstrated by multiple in vitro and in vivo studies, menopause-related decline of circulating estrogen may induce the disturbance of metabolic signals and a significant decrease in bioenergetics, which could trigger an increased incidence of late-onset Alzheimer's disease, type 2 diabetes mellitus, hypertension, and cardiovascular diseases in postmenopausal women. In this article, we have systematically reviewed the role of estrogen and ERs in body composition and lipid/glucose profile variation occurring with menopause, which may provide a better insight into the efficacy of hormone therapy in maintaining energy metabolic homeostasis and hold a clue for development of novel therapeutic approaches for target tissue diseases.

7.
J Vis Exp ; (200)2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37955381

RESUMO

Here we report a standard procedure for the isolation and identification of limbal niche cells (LNCs). Limbus tissue obtained from an eye bank was used for LNCs isolation. The tissue was divided into 12 pieces under aseptic conditions and digested for 18 h at 37 °C in the cell culture incubator using collagenase A to obtain cell clusters with LNCs and limbal epithelial progenitor cells. The cell clusters were further digested for 15 min at 37 °C using 0.25% trypsin-EDTA to obtain single cells and then cultured in modified embryonic stem cell medium (MESCM) on a plastic surface coated with 5% Matrigel. Cells were passaged upon 70% confluence, and LNCs were identified using immunofluorescence, real-time quantitative PCR (qPCR), and flow cytometry. Primary LNCs were isolated and passaged more than 12 times. The proliferation activity of LNCs from P4 to P6 was the highest. LNCs expressed higher stem cell markers than BMMSCs (SCF, Nestin, Rex1, SSEA4, CD73, CD90, MSX1, P75NTR, and PDGFRß). Furthermore, results showed that P4 LNCs uniformly expressed VIM, CD90, CD105, and PDGFRß, but not Pan-CK, which could be used as a marker for the identification of LNCs. Flow cytometric analysis showed that approximately 95%, 97%, 92%, and 11% of LNCs expressed CD73, CD90, CD105, and SCF respectively, while they were 68%, 99%, 20%, and 3% in BMMSCs. The standard process for LNC isolation and identification could provide a reliable laboratory basis for the widespread use of LNCs.


Assuntos
Epitélio Corneano , Limbo da Córnea , Células-Tronco , Técnicas de Cultura de Células , Separação Celular/métodos , Imunofluorescência , Células Cultivadas , Diferenciação Celular , Células Epiteliais , Nicho de Células-Tronco
8.
Front Endocrinol (Lausanne) ; 13: 982953, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36120452

RESUMO

Many patients with congenital adrenal hyperplasia (CAH) refrain from seeking pregnancy, suffer from infertility or worry about pregnancy complications, mainly due to genitalia abnormalities, anovulation, unreceptive endometrium and metabolic disturbances. Despite those challenges, many live births have been reported. In this systematic review, we focused on the key to successful assisted reproduction strategies and the potential pregnancy complications. We did a systematic literature search of Pubmed, Medline and Scopus for articles reporting successful pregnancies in CAH other than 21-hydroxylase deficiency, and found 25 studies reporting 39 pregnancies covering deficiency in steroidogenic acute regulatory protein, 17α-hydroxylase/17,20-lyase, 11ß-hydroxylase, P450 oxidoreductase, cytochrome b5 and 3ß-hydroxysteroid dehydrogenase. We summarized various clinical manifestations and tailored reproduction strategy for each subtype. Furthermore, a meta-analysis was performed to evaluate the pregnancy complications of CAH patients. A total of 19 cross-sectional or cohort studies involving 1311 pregnancies of classic and non-classic CAH patients were included. Surprisingly, as high as 5.5% (95% CI 2.3%-9.7%) of pregnancies were electively aborted, and the risk was significantly higher in those studies with a larger proportion of classic CAH than those with only non-classical patients (8.43% (4.1%-13.81%) VS 3.75%(1.2%-7.49%)), which called for better family planning. Pooled incidence of miscarriage was 18.2% (13.4%-23.4%) with a relative risk (RR) of 1.86 (1.27-2.72) compared to control. Glucocorticoid treatment in non-classical CAH patients significantly lowered the miscarriage rate when compared to the untreated group (RR 0.25 (0.13-0.47)). CAH patients were also more susceptible to gestational diabetes mellitus, with a prevalence of 7.3% (2.4%-14.1%) and a RR 2.57 (1.29-5.12). However, risks of preeclampsia, preterm birth and small for gestational age were not significantly different. 67.8% (50.8%-86.9%) CAH patients underwent Cesarean delivery, 3.86 (1.66-8.97) times the risk of the control group. These results showed that fertility is possible for CAH patients but special care was necessary when planning, seeking and during pregnancy. Systematic Review Registration: PROSPERO https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=342642, CRD42022342642.


Assuntos
Aborto Espontâneo , Hiperplasia Suprarrenal Congênita , Complicações na Gravidez , Nascimento Prematuro , Aborto Espontâneo/epidemiologia , Aborto Espontâneo/etiologia , Hiperplasia Suprarrenal Congênita/complicações , Hiperplasia Suprarrenal Congênita/epidemiologia , Hiperplasia Suprarrenal Congênita/terapia , Estudos Transversais , Citocromos b5 , Feminino , Glucocorticoides/uso terapêutico , Humanos , Hidroxiesteroide Desidrogenases , Recém-Nascido , Gravidez , Complicações na Gravidez/tratamento farmacológico , Complicações na Gravidez/epidemiologia , Reprodução , Esteroide 17-alfa-Hidroxilase
9.
Front Endocrinol (Lausanne) ; 13: 971616, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36133317

RESUMO

This study was to explore whether postponing frozen embryo transfers (FET) after oocyte pickup (OPU) improves clinical and neonatal outcomes. From May 2018 to Dec 2020, a total of 1109 patients underwent their first OPU cycles adopting a non-selective freeze-all policy were included in this retrospective cohort study. In the immediate group (n=219), patients underwent FET in the first menstrual cycle after OPU, and patients in the postponed group (n=890) waited for more than 1 menstrual cycle after OPU to perform FET. A propensity score matching (PSM) model was used to evaluate the clinical outcomes and neonatal outcomes between the two groups. There were 209 patients in the immediate group and 499 patients in the postponed one after PSM. Patients waited for a significantly shorter period for FET in the immediate group (30.74 ± 3.85 days) compared with the postponed group (80.39 ± 26.25 days, P<0.01). The clinical pregnancy rate (CPR) and live birth rate (LBR) in the immediate group were 58.4% and 48.3%, respectively, which were comparable to those of the postponed one (58.1%, 49.7%, P > 0.05). No statistical significance was found in the average birth weight (3088.82 ± 565.35 g vs 3038.64 ± 625.78 g, P > 0.05) and height (49.08 ± 1.87 cm vs 49.30 ± 2.52 cm) of neonates between the two groups. The gender ratio, the incidence of macrosomia and low birth weight did not differ significantly between the two groups. In conclusion, postponing FET does not improve clinical and neonatal outcomes. If patients have no contraindications, FETs should be carried out immediately after OPU.


Assuntos
Criopreservação , Recuperação de Oócitos , Peso ao Nascer , Transferência Embrionária , Feminino , Humanos , Gravidez , Pontuação de Propensão , Estudos Retrospectivos
10.
Front Endocrinol (Lausanne) ; 13: 1013894, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36704038

RESUMO

Primary ovarian insufficiency (POI) is among the foremost causes of women infertility due to premature partial or total loss of ovarian function. Resistant ovary syndrome (ROS) is a subtype of POI manifested as normal ovarian reserve but insensitive to gonadotropin stimulation. Inactivating variants of follicle-stimulating hormone receptor (FSHR), a class A G-protein coupled receptor, have been associated with POI and are inherited via an autosomal recessive pattern. In this study, we investigated the genetic causes of a primary infertility patient manifested as POI with ROS, and elucidated the structural and functional impact of variants of uncertain significance. Next-generation sequencing (NGS) combined with Sanger sequencing revealed novel compound heterozygous FSHR variants: c.1384G>C/p.Ala462Pro and c.1862C>T/p.Ala621Val, inherited from her father and mother, respectively. The two altered amino acid sequences, localized in the third and seventh transmembrane helix of FSHR, were predicted as deleterious by in silico prediction. In vitro experiments revealed that the p.Ala462Pro variant resulted in barely detectable levels of intracellular signaling both in cAMP-dependent CRE-reporter activity and ERK activation and displayed a severely reduced plasma membrane receptor expression. In contrast, the p.Ala621Val variant resulted in partial loss of receptor activation without disruption of cell surface expression. In conclusion, two unreported inactivating FSHR variants potentially responsible for POI with ROS were first identified. This study expands the current phenotypic and genotypic spectrum of POI.


Assuntos
Infertilidade Feminina , Insuficiência Ovariana Primária , Humanos , Feminino , Insuficiência Ovariana Primária/genética , Insuficiência Ovariana Primária/metabolismo , Receptores do FSH/genética , Receptores do FSH/metabolismo , Espécies Reativas de Oxigênio , Genótipo
11.
Polymers (Basel) ; 13(19)2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34641093

RESUMO

Nanocomposite foam with a large expansion ratio and thin cell walls is promising for electromagnetic interference (EMI) shielding materials, due to the low electromagnetic (EM) reflection and high EM absorption. To overcome the dimensional limitation from two-dimension (2D) thin walls on the construction of conductive network, a strategy combining hybrid conductive nanofillers in semi-crystalline matrix together with supercritical CO2 (scCO2) foaming was applied: (1) one-dimension (1D) CNTs with moderate aspect ratio was used to minimize the dimensional confinement from 2D thin walls while constructing the main EM absorbing network; (2) zero-dimension (0D) carbon black (CB) with no dimensional confinement was used to connect the separated CNTs in thin walls and to expand the EM absorbing network; (3) scCO2 foaming was applied to obtain a cellular structure with multi-layer thin walls and a large amount of air cells to reduce the reflected EM; (4) semi-crystalline polymer was selected so that the rheological behavior could be adjusted by optimizing crystallization and filler content to regulate the cellular structure. Consequently, an advanced material featured as lightweight, high EM absorption and low EM reflection was obtained at 0.48 vol.% hybrid nanofillers and a density of 0.067 g/cm3, whose specific EMI shielding performance was 183 dB cm3/g.

12.
J Int Med Res ; 48(8): 300060520935313, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32776821

RESUMO

OBJECTIVE: Observational studies have shown that circulating vitamin D (VitD) deficiency is associated with atherogenic lipid patterns among polycystic ovary syndrome (PCOS) patients. However, interventional studies have shown inconsistent results. The aim of this meta-analysis was to investigate how VitD supplementation influences lipid indices in PCOS patients. METHODS: The authors searched four electronic databases through August 2019 to identify randomized controlled trials (RCTs) that assessed the effect of VitD intervention on serum lipids among PCOS patients. Mean differences were generated for statistical evaluation. RESULTS: We included eight studies and performed nine comparisons across 467 participants. VitD supplementation reduced serum triglyceride levels (-11.88 mg/dL; 95% confidence interval [CI]: -17.03 to -6.73), total cholesterol (-9.09 mg/dL; 95% CI: -14.90 to -3.29), low-density lipoprotein cholesterol (-5.22 mg/dL; 95% CI: -10.32 to -0.13), and very-low-density lipoprotein cholesterol (-2.43 mg/dL; 95% CI: -3.69 to -1.17) compared with no VitD supplementation. However, high-density lipoprotein cholesterol levels showed no differences with or without VitD supplementation (-0.39 mg/dL; 95% CI: -1.39 to 0.61). CONCLUSIONS: VitD supplementation improved serum lipid levels among PCOS patients, but serum high-density lipoprotein cholesterol levels were not changed. VitD intervention might benefit PCOS patients who are at high risk of an atherogenic lipid profile.


Assuntos
Síndrome do Ovário Policístico , Suplementos Nutricionais , Feminino , Humanos , Lipídeos , Síndrome do Ovário Policístico/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Triglicerídeos , Vitamina D
13.
Medicine (Baltimore) ; 99(25): e20730, 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32569212

RESUMO

BACKGROUND: Published findings on perinatal outcomes of multifetal pregnancy reduction (MPR) of dichorionic diamniotic (DCDA) twin pregnancy to singleton are controversial. We performed a meta-analysis to appraise the effects of MPR of DCDA twin pregnancy versus expectant management on perinatal outcomes. METHODS: Four electronic databases were searched from their inception to June 15, 2019, to identify publications that appraised MPR before 15 weeks of gestation. Studies reporting perinatal outcomes of both MPR of DCDA twin pregnancy to singleton and expectant management were considered. The relative risks (RRs) and mean differences with 95% confidence intervals (CIs) were pooled using a random-effects model. RESULTS: Six studies involving 7398 participants showed that MPR of DCDA twin pregnancy to singleton was associated with a lower risk of preterm birth (5 studies with 7297 participants; RR: 0.30, 95% CI: 0.22-0.40; P < .001) and higher birth weight (4 studies with 5763 participants; mean differences: 548.10 g, 95% CI: 424.04-672.15; P < .001) than expectant management; there was no difference in the occurrence of miscarriages (5 studies with 7355 participants; RR: 1.57, 95% CI: 0.90-2.75; P = .11). Sensitivity analysis showed that all the results were stable and reliable, with the omission of 2 studies with serious risk of bias. CONCLUSION: Compared to expectant management, MPR of DCDA twin pregnancy to singleton prevents preterm birth and low birth weight, without increasing the risk of miscarriages. Regarding perinatal morbidity related to preterm birth, MPR can be reserved as a remediation measure to improve the perinatal outcomes of DCDA twin pregnancies.


Assuntos
Resultado da Gravidez , Redução de Gravidez Multifetal , Adulto , Âmnio/anatomia & histologia , Córion/anatomia & histologia , Feminino , Humanos , Gravidez , Gravidez de Gêmeos , Gemelação Dizigótica , Gêmeos Dizigóticos , Conduta Expectante
14.
Oncol Lett ; 8(6): 2523-2526, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25360170

RESUMO

Few reports have explored laparoscopic adnexal tumorectomy as a treatment for large and symptomatic ovarian leiomyomas during pregnancy. The current study presents the case of a patient with a large and symptomatic ovarian leiomyoma at 14 weeks of pregnancy. A laparoscopic adnexal tumorectomy was performed without complications. The laparoscopic management of large primary ovarian leiomyoma during pregnancy has not been reported in literature. Therefore, laparoscopy may be considered as a minimally invasive and feasible alternative to laparotomy for the treatment of large ovarian solid tumors during pregnancy, resulting in reduced postoperative pain, a smaller scar and shorter recovery time. By contrast, with respect to the ovarian solid tumor, surgery prior to gestation is advised, even for tumors of <3 cm in diameter, due to the probability of rapid growth of the tumor during pregnancy.

15.
Eur J Pharmacol ; 616(1-3): 200-5, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19549516

RESUMO

Apigenin is shown to have cardiovascular effects, but the effects of apigenin on aortas injured by exogenous oxidants are unknown. The objective of this study was to investigate the effect of apigenin on endothelium-dependent vasorelaxation in isolated rat aortic rings exposed to superoxide anion produced by pyrogallol, and its mechanism. The male Sprague-Dawley rat thoracic aorta was rapidly dissected out and the effect of apigenin on tension of aortic rings pretreated with 500 microM pyrogallol, inducing oxidative stress injury, was measured. The activity of nitric oxide synthase (NOS), the level of nitric oxide (NO) and the inhibition of superoxide anion in aortic tissues were measured. We found that pretreatment with pyrogallol concentration-dependently decreased acetylcholine-induced endothelium-dependent vasorelaxation. Apigenin (0.5-72.0 microM) evoked a concentration-dependent relaxation in aortas (pD(2): 5.304+/-0.049), which was weakened by L-NAME (the maximal relaxation fell from 87.6+/-6.7% to 37.1+/-8.8%, P<0.01), but not by aminoguanidine and indomethacin. Apigenin markedly attenuated the inhibition of vasorelaxation induced by pyrogallol (the maximal relaxation elevated from 55.8%+/-6.6% to 69.5%+/-6.4%, and the pD(2) increased from 6.559+/-0.119 to 7.057+/-0.145, P<0.01) and increased the inhibition of superoxide anion (from 94.6% to 74.5%), the NO level (from 77.1% to 94.4%), and the constitutive NOS activity (from 35.1% to 62.5%). These results indicate that pyrogallol decreased endothelium-dependent vasorelaxation in rat aortas via oxidative stress, which was markedly attenuated by apigenin. This may be mediated by weakening the oxidative stress and the NO reduction.


Assuntos
Aorta/efeitos dos fármacos , Aorta/fisiologia , Apigenina/farmacologia , Fármacos Cardiovasculares/farmacologia , Endotélio Vascular/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Acetilcolina/farmacologia , Animais , Aorta/enzimologia , Aorta/metabolismo , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/enzimologia , Aorta Torácica/metabolismo , Aorta Torácica/fisiologia , Técnicas In Vitro , Masculino , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Fenilefrina/farmacologia , Pirogalol/farmacologia , Ratos , Ratos Sprague-Dawley , Superóxidos/antagonistas & inibidores , Vasodilatação/efeitos dos fármacos
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