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1.
Metabolites ; 13(10)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37887417

RESUMO

Oral hormonal contraceptive users carry the risk of venous thrombosis and increased mortality. This study aimed to comprehensively profile the serum metabolome of participants using a combination of drospirenone (DRSP) and ethinyl estradiol (EE) containing oral contraceptives (COCs). The MxP Quant 500 kit for liquid chromatography mass tandem spectrometry (LC-MS/MS) was used to analyse the 22 controls and 44 COC users (22 on a low EE dose (DRSP/20EE) and 22 on a higher EE dose (DRSP/30EE)). The kit's results were compared to our internally developed untargeted and targeted metabolomics methods previously applied to this cohort. Of the 630 metabolites included in the method, 277 provided desirable results (consistently detected above their detection limits), and of these, 5 had p-values < 0.05, including betaine, glutamine, cortisol, glycine, and choline. Notably, these variations were observed between the control and COC groups, rather than among the two COC groups. Partial least squares-discriminant analysis revealed 49 compounds with VIP values ≥ 1, including amino acids and their derivatives, ceramides, phosphatidylcholines, and triglycerides, among others. Ten differential compounds were consistent with our previous studies, reinforcing the notion of COCs inducing a prothrombotic state and increased oxidative stress. Although only a limited number of compounds were deemed usable, these were quantified with high reliability and facilitated the identification of meaningful biological differences among the sample groups. In addition to substantiating known drug-induced variations, new hypotheses were also generated.

3.
Thromb Haemost ; 122(1): 67-79, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33906245

RESUMO

Case-control and observational studies have provided a plausible mechanistic link between clot structure and thrombosis. We aimed to identify lifestyle, demographic, biochemical, and genetic factors that influence changes in total fibrinogen concentration and clot properties over a 10-year period in 2,010 black South Africans. Clot properties were assessed with turbidimetry and included lag time, slope, maximum absorbance, and clot lysis time. Linear mixed models with restricted maximum likelihood were used to determine whether (1) outcome variables changed over the 10-year period; (2) demographic and lifestyle variables, biochemical variables, and fibrinogen single-nucleotide polymorphisms influenced the change in outcome variables over the 10-year period; and (3) there was an interaction between the exposures and time in predicting the outcomes. A procoagulant risk score was furthermore created, and multinomial logistic regression was used to determine the exposures that were associated with the different risk score categories. In this population setting, female gender, obesity, poor glycemic control, increased low-density lipoprotein cholesterol, and decreased high-density lipoprotein cholesterol contributed to the enhanced progression to prothrombotic clot properties with increasing age. Alcohol consumption on the other hand, offered a protective effect. The above evidence suggest that the appropriate lifestyle changes can improve fibrin clot properties on a population level, decreasing cardiovascular disease risk and thus alleviate the strain on the medical health care system.


Assuntos
Micropartículas Derivadas de Células/fisiologia , Fibrina/análise , Comportamento de Redução do Risco , Trombose/fisiopatologia , Adulto , Estudos de Casos e Controles , Feminino , Fibrina/biossíntese , Fibrina/classificação , Hemólise/fisiologia , Humanos , Ferro/sangue , Ferro/metabolismo , Masculino , Pessoa de Meia-Idade , Trombose/sangue
4.
Microsc Microanal ; 26(5): 1007-1013, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778190

RESUMO

Combined oral contraceptives (COCs) are commonly prescribed and increase the risk of venous thromboembolism (VTE). We have previously found that two COCs, both containing drospirenone (DRSP) and ethinyl estradiol (EE), cause spontaneous fibrin formation in whole blood. The aim of this study was, therefore, to use platelet-poor plasma (PPP) from the same cohort of DRSP/EE users to determine the impact of these COCs on the fibrin component, specifically the fibrin clot viscoelasticity, turbidimetry, and biophysical traits. PPP from 25 females per test group and a control group (n = 25) were analyzed using thromboelastography (TEG), turbidimetry, and scanning electron microscopy. The results highlight abnormal fibrin clot formation, lysis, and architecture; DRSP/20EE showed the greatest effect. DRSP/EE use increased the fibrin fiber diameter and showed dense matted clots. Only when the influence of COCs on the structural properties and behavior of fibrin fibers during thrombus formation and lysis is better understood are we able to predict and prevent coagulopathies associated with these synthetic hormones. Clinical practitioners should take this into consideration for female patients that either have comorbidities, which could burden the coagulation system, or may be exposed to external factors that could increase their risk for VTE.


Assuntos
Testes de Coagulação Sanguínea , Coagulação Sanguínea/efeitos dos fármacos , Anticoncepcionais Orais Combinados/farmacologia , Fibrina/química , Fibrina/ultraestrutura , Adolescente , Adulto , Androstenos , Etinilestradiol/farmacologia , Feminino , Fibrina/farmacologia , Humanos , Masculino , Microscopia Eletrônica de Varredura , Tromboelastografia , Trombose , Tromboembolia Venosa , Viscosidade , Adulto Jovem
5.
OMICS ; 24(7): 404-414, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32471328

RESUMO

The association between hypercoagulability and use of drospirenone (DRSP) and ethinylestradiol (EE) containing combined oral contraceptives (COCs) is an important clinical concern. We have previously reported that the two formulations of DRSP combined with EE (namely, DRSP/20EE and DRSP/30EE) bring about a prothrombotic state in hemostatic traits of female users. We report here the serum metabolomic changes in the same study cohort in relation to the attendant prothrombotic state induced by COC use, thus offering new insights on the underlying biochemical mechanisms contributing to the altered coagulatory profile with COC use. A total of 78 healthy women participated in this study and were grouped as follows: control group not using oral contraceptives (n = 25), DRSP/20EE group (n = 27), and DRSP/30EE group (n = 26). Untargeted metabolomics revealed changes in amino acid concentrations, particularly a decrease in glycine and an increase in both cysteine and lanthionine in the serum, accompanied by variations in oxidative stress markers in the COC users compared with the controls. Of importance, this study is the first to link specific amino acid variations, serum metabolites, and the oxidative metabolic profile with DRSP/EE use. These molecular changes could be linked to specific biophysical coagulatory alterations observed in the same individuals. These new findings lend evidence on the metabolomic substrates of the prothrombotic state associated with COC use in women and informs future personalized/precision medicine research. Moreover, we underscore the importance of an interdisciplinary approach to evaluate venous thrombotic risk associated with COC use.


Assuntos
Androstenos/efeitos adversos , Biomarcadores/sangue , Coagulação Sanguínea/efeitos dos fármacos , Anticoncepcionais Orais Combinados/efeitos adversos , Etinilestradiol/efeitos adversos , Metaboloma , Adolescente , Adulto , Androstenos/administração & dosagem , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Plaquetas/ultraestrutura , Anticoncepcionais Orais Combinados/administração & dosagem , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Eritrócitos/ultraestrutura , Etinilestradiol/administração & dosagem , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Metabolômica/métodos , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Trombose/sangue , Trombose/diagnóstico , Trombose/etiologia , Adulto Jovem
6.
Microsc Res Tech ; 81(12): 1489-1500, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30365192

RESUMO

There are several possible mechanisms by which combined oral contraceptives (COC) use increase venous thromboembolism (VTE) risk. Melodene® is a monophasic COC containing the third-generation progestin Gestodene (GSD), which is associated with increased risk of VTE. Therefore, the aim of this study was to investigate the possible alterations in viscoelastic parameters of whole blood and plasma clots along with the biophysical characteristics of erythrocytes and specifically fibrin fibers in females using a COC containing GSD. GSD appeared to have a significant impact on the biophysical characteristics of fibrin fiber networks. When GSD is combined with ethinylestradiol the viscoelastic properties of whole blood clots tend to become more prothrombotic. The alterations to and aggregation of erythrocytes accompanied with spontaneous formation of a fibrin "blanket" provides a possible mechanism for the increased occurrence of "red" clots, which can lead to occlusions in the vascular system. Thus, the increased risk of VTE associated with these COCs can be attributed to these erythrocyte-and-fibrin-rich-clots occluding venous vessels. However, our findings also propose that these changes to the biophysical properties of both erythrocytes and fibrin, specifically spontaneous expansion of deformed fibrin networks, can also occlude vessels in the microcirculation, which could have lasting, subclinical complications for female users. We recommend that a thorough risk assessment, with specific focus on coagulation and other factors affecting fibrin formation, be done for each female before prescribing a GSD-containing COC. Females that "qualify" then need to be monitored on a regular basis to lower the risk of thrombotic events. RESEARCH HIGHLIGHTS: Gestodene in combination with ethinyl estradiol significantly impacts the biophysical characteristics of erythrocytes and fibrin fiber networks. These changes, specifically spontaneous expansion of deformed fibrin networks, can occlude vessels in the microcirculation, which could have lasting, subclinical complications for the female user. The changes observed for specifically erythrocytes and fibrin show that the hormone formulation investigated contribute to a thrombogenic profile for female users.


Assuntos
Anticoncepcionais Orais Combinados/efeitos adversos , Norpregnenos/efeitos adversos , Trombose/etiologia , Adulto , Coagulação Sanguínea/efeitos dos fármacos , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Feminino , Fibrina/metabolismo , Humanos , Trombose/sangue , Trombose/metabolismo , Adulto Jovem
7.
Cardiovasc Diabetol ; 15: 52, 2016 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-27036108

RESUMO

BACKGROUND: The function of platelets have extended way beyond the horizon of haemostasis and thrombosis, and are recognised as active participants in vascular inflammation, as well as in prothrombotic complications of cardiovascular diseases. We describe and compare platelet function in type II diabetes (with and without cardiovascular manifestation) and healthy individuals using scanning electron microscopy and flow cytometry. METHODS: Thirty subjects were recruited per group and informed consent was obtained from all participants. Diabetic patients were recruited from the diabetic clinic of the Steve Biko Academic Hospital (South Africa). Blood samples were drawn from all participants so that platelet specific antigens were analyzed in citrated whole blood. The platelet parameters used in the study were platelet identifiers (CD41 and CD42) and markers of platelet activation (CD62 and CD63). RESULTS: Results show that, compared to healthy individuals, both diabetic groups showed a significant difference in both platelet identifiers (CD41-PE, CD42b-PE) as well as markers indicating platelet activation (CD62P-PE and CD63-PE). INTERPRETATION: The flow cytometric data shows that the platelet surface receptors and platelet activation are statistically elevated. This is suggestive of enhanced platelet activation and it appears as if platelets are displaying 'angry' behaviour. The lysosomal granules may play a significant role in diabetes with cardiovascular complications. These results were confirmed by ultrastructural analysis.


Assuntos
Plaquetas/citologia , Diabetes Mellitus Tipo 2/sangue , Citometria de Fluxo , Ativação Plaquetária/fisiologia , Trombose/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/análise , Biomarcadores/sangue , Feminino , Citometria de Fluxo/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Ativação Plaquetária/imunologia , Adulto Jovem
8.
Rheumatol Int ; 32(6): 1611-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21331577

RESUMO

Rheumatoid arthritis is a chronic inflammatory condition that affects mainly synovial joints and has an impact on approximately 1% of the Western population. The coagulation process is altered in this condition, and this is frequently complicated by thrombocytosis. Changes in fibrin morphology have been linked with inflammation, and this, in turn, plays an important role in thrombosis. Changes in the fibrin fiber formation cause the alterations observed in thrombus morphology. In the current study, the ultrastructure of platelets and fibrin networks was investigated to determine whether any morphological changes are present in these structures in patients suffering from rheumatoid arthritis. Six patients diagnosed with rheumatoid arthritis took part in this study, and their clot morphology was compared to that of control subjects. Citrated blood with and without the addition of thrombin was used. Results indicated that the fibrin networks in the arthritis patients formed thick, matted layers. This matted appearance is due to a changed ultrastructure of the minor, thin fibers. Also, in these patients, spontaneous networks were created without the addition of thrombin, which indicates an abnormal hemostatic protein functioning, and the latter is expressed as visible changes in ultrastructure.


Assuntos
Artrite Reumatoide/patologia , Coagulação Sanguínea , Plaquetas/ultraestrutura , Fibrina/ultraestrutura , Microscopia Eletrônica de Varredura , Adulto , Artrite Reumatoide/sangue , Artrite Reumatoide/imunologia , Plaquetas/metabolismo , Estudos de Casos e Controles , Feminino , Fibrina/metabolismo , Humanos , Masculino , África do Sul , Trombina/metabolismo
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