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1.
PLoS One ; 18(12): e0295959, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38134043

RESUMEN

Progestin-only injectable contraceptives, mainly depo-medroxyprogesterone acetate intramuscular (DMPA-IM), are the most widely used contraceptive methods in sub-Saharan Africa. Insufficient robust data on their relative side-effects and serum concentrations limit understanding of reported outcomes in contraception trials. The WHICH clinical trial randomized HIV-negative women to DMPA-IM (n = 262) or norethisterone enanthate (NET-EN) (n = 259) at two South African sites between 2018-2019. We measured serum concentrations of study and non-study progestins at initiation (D0) and peak serum levels, one week after the 24-week injection [25 weeks (25W)], (n = 435) and investigated associations between study progestin levels, and BMI and weight of participants. Peak median serum concentrations were 6.59 (IQR 4.80; 8.70) nM for medroxyprogesterone (MPA) (n = 161) and 13.6 (IQR 9.01; 19.0) nM for norethisterone (NET) (n = 155). MPA was the most commonly quantifiable non-study progestin at D0 in both arms (54%) and at 25W in the NET-EN arm (27%), followed by NET at D0 in both arms (29%) and at 25W in the DMPA-IM arm (19%). Levonorgestrel was quantifiable in both arms [D0 (6.9%); 25W (3.4%)], while other progestins were quantifiable in ≤ 14 participants. Significant negative time-varying associations were detected between MPA and NET concentrations and weight and BMI in both contraceptive arms and a significant increase was detected for peak serum progestin concentrations for normal weight versus obese women. Contraceptive-related reported outcomes are likely confounded by MPA, more so than NET, with reported DMPA-IM effects likely underestimated, at sites where DMPA-IM is widely used, due to misreporting of contraceptive use before and during trials, and 'tail' effects of DMPA-IM use more than six months before trial enrolment. Peak serum levels of MPA and NET are negatively associated with BMI and weight, suggesting another source of variability between trial outcomes and a potential increase in side-effects for normal weight versus overweight and obese women. Trail registration: The clinical trial was registered with the Pan African Clinical Trials Registry (PACTR 202009758229976).


Asunto(s)
Acetato de Medroxiprogesterona , Progestinas , Femenino , Humanos , Acetato de Medroxiprogesterona/efectos adversos , Anticonceptivos , Índice de Masa Corporal , Noretindrona/farmacología , Obesidad
2.
Am J Reprod Immunol ; 88(6): e13643, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36302121

RESUMEN

PROBLEM: Both luteal phase progesterone (P4) levels and use of the intramuscular (IM) injectable progestin-only contraceptive depo-medroxyprogesterone acetate (DMPA-IM) have been linked to increased S/HIV acquisition in animal, clinical and in vitro models. Several plausible mechanisms could explain MPA-induced HIV-1 acquisition while those for the luteal phase are underexplored. METHOD OF STUDY: Peripheral blood mononuclear cells (PBMCs) were treated with P4 and estrogen at concentrations mimicking the luteal phase, follicular phase or with levels of MPA mimicking peak serum levels in DMPA-IM users. Cells were infected with an R5-tropic infectious molecular clone and HIV-1 infection was measured. A role for the glucocorticoid receptor (GR) was investigated using the GR/PR antagonist RU486. CCR5 protein levels and activation status, assessed by levels of the activation marker CD69, were measured by flow cytometry after treatment in vitro and in PBMCs from naturally-cycling women or DMPA-IM users. RESULTS: Both MPA and luteal phase hormones significantly increased HIV-1 infection in vitro. However, MPA but not luteal phase hormones increased the CD4+/CD8+ T cell ratio, CCR5 protein expression on CD4+ T cells and increased expression of the activation marker CD69. The GR is involved in MPA-induced, but not luteal phase hormone-induced increased HIV-1 infection. In DMPA-IM users, the frequency of CCR5-expressing CD3+ and CD8+ cells was higher than for women in the luteal phase. CONCLUSIONS: MPA increases HIV-1 infection in a manner different from that of luteal phase hormones, most likely involving the GR and at least in part changes in the frequency and/or expression of CCR5 and CD69.


Asunto(s)
Anticonceptivos Femeninos , Infecciones por VIH , VIH-1 , Femenino , Humanos , Anticonceptivos Femeninos/farmacología , Infecciones por VIH/tratamiento farmacológico , VIH-1/fisiología , Leucocitos Mononucleares/metabolismo , Acetato de Medroxiprogesterona/farmacología , Ciclo Menstrual , Progesterona , Receptores de Glucocorticoides/metabolismo
3.
Steroids ; 187: 109100, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35964796

RESUMEN

Quantification of serum progestin levels in clinical contraceptive studies is now routinely performed to understand progestin pharmacokinetics and to correct for unreliable self-reporting of contraceptive use by study participants. Many such studies are focussed on the three-monthly progestin-only intramuscular (IM) injectable contraceptive depot medroxyprogesterone acetate (DMPA-IM). Methods commonly used to measure serum MPA levels include liquid chromatography coupled to mass spectrometry (LC/MS) and radioimmunoassay (RIA); however, RIA methods have not been used in recent years. We review the available literature and find that these methods vary widely in terms of use of organic solvent extraction, use of derivitization and choice of organic solvent and chromatography columns. There is a lack of standardization of LC/MS methodology, including a lack of detailed extraction protocols. Limited evidence suggests that RIA, without organic solvent extraction, likely over-estimates progestin levels. Maximum MPA concentrations in the first two weeks post-injection show wide inter-individual and inter-study variation, regardless of quantification method used. Standardization of quantification methods and sampling time post-injection is required to improve interpretation of clinical data, in particular the side effects arising at different times depending on the pharmacokinetic profile unique to injectable contraceptives.


Asunto(s)
Anticonceptivos Femeninos , Acetato de Medroxiprogesterona , Anticonceptivos , Femenino , Humanos , Progestinas , Radioinmunoensayo , Solventes
4.
Pharmacol Ther ; 222: 107789, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33316287

RESUMEN

Many different forms of hormonal contraception are used by millions of women worldwide. These contraceptives differ in the dose and type of synthetic progestogenic compound (progestin) used, as well as the route of administration and whether or not they contain estrogenic compounds. There is an increasing awareness that different forms of contraception and different progestins have different side-effect profiles, in particular their cardiovascular effects, effects on reproductive cancers and susceptibility to infectious diseases. There is a need to develop new methods to suit different needs and with minimal risks, especially in under-resourced areas. This requires a better understanding of the pharmacokinetics, metabolism, serum and tissue concentrations of progestins used in contraception as well as the biological activities of progestins and their metabolites via steroid receptors. Here we review the current knowledge on these topics and identify the research gaps. We show that there is a paucity of research on most of these topics for most progestins. We find that major impediments to clear conclusions on these topics include a lack of standardized methodologies, comparisons between non-parallel clinical studies and variability of data on serum concentrations between and within studies. The latter is most likely due, at least in part, to differences in intrinsic characteristics of participants. The review highlights the importance of insight on these topics in order to provide the best contraceptive options to women with minimal risks.


Asunto(s)
Anticoncepción , Anticonceptivos , Progestinas , Anticoncepción/efectos adversos , Anticoncepción/métodos , Anticonceptivos/sangre , Anticonceptivos/metabolismo , Anticonceptivos/farmacocinética , Femenino , Humanos , Progestinas/sangre , Progestinas/metabolismo , Progestinas/farmacocinética
5.
Artículo en Inglés | MEDLINE | ID: mdl-31658973

RESUMEN

Millions of women are exposed simultaneously to antiretroviral drugs (ARVs) and progestin-based hormonal contraceptives. Yet the reciprocal modulation by ARVs and progestins of their intracellular functions is relatively unexplored. We investigated the effects of tenofovir disoproxil fumarate (TDF) and dapivirine (DPV), alone and in the presence of select steroids and progestins, on cell viability, steroid-regulated immunomodulatory gene expression, activation of steroid receptors, and anti-HIV-1 activity in vitro Both TDF and DPV modulated the transcriptional efficacy of a glucocorticoid agonist via the glucocorticoid receptor (GR) in the U2OS cell line. In TZM-bl cells, DPV induced the expression of the proinflammatory interleukin 8 (IL-8) gene while TDF significantly increased medroxyprogesterone acetate (MPA)-induced expression of the anti-inflammatory glucocorticoid-induced leucine zipper (GILZ) gene. However, peripheral blood mononuclear cell (PBMC) and ectocervical explant tissue viability and gene expression results, along with TZM-bl HIV-1 infection data, are reassuring and suggest that TDF and DPV, in combination with dexamethasone (DEX) or MPA, do not reciprocally modulate key biological effects in primary cells and tissue. We show for the first time that TDF induces progestogen-independent activation of the progesterone receptor (PR) in a cell line. The ability of TDF and DPV to influence GR and PR activity suggests that their use may be associated with steroid receptor-mediated off-target effects. This, together with cell line and individual donor gene expression responses in the primary models, raises concerns that reciprocal modulation may cause side effects in a cell- and donor-specific manner in vivo.


Asunto(s)
Antirretrovirales/efectos adversos , Antirretrovirales/farmacología , Receptores de Esteroides/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Inflamación/metabolismo , Células Madre de Sangre Periférica/efectos de los fármacos , Células Madre de Sangre Periférica/metabolismo , Progestinas/metabolismo , Pirimidinas/efectos adversos , Pirimidinas/farmacología , Receptores de Glucocorticoides/metabolismo , Receptores de Progesterona/metabolismo , Tenofovir/efectos adversos , Tenofovir/farmacología , Factores de Transcripción/metabolismo
6.
Trends Microbiol ; 26(11): 891-892, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30292640

RESUMEN

Persistence of the latent reservoir remains a challenge to curing HIV infection. Using shRNA screening, new insights into the molecular mechanisms underlying latency regulation indicate that the estrogen receptor is a potent repressor of proviral reactivation and may serve as a promising therapeutic target in combination with other latency-reversing agents.


Asunto(s)
Infecciones por VIH , VIH-1 , Receptor alfa de Estrógeno , Humanos , Receptores de Estrógenos , Latencia del Virus
7.
PLoS One ; 13(4): e0196043, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29698514

RESUMEN

High usage of progestin-only injectable contraceptives, which include the intramuscular injectables depo-medroxyprogesterone acetate (DMPA-IM, Depo-Provera) and norethisterone (NET) enanthate (NET-EN or Nur-Isterate), correlates worldwide with areas of high HIV-1 prevalence. Epidemiological data show a significant association between usage of DMPA-IM and increased HIV-1 acquisition but no such association from limited data for NET-EN. Whether MPA and NET have similar effects on HIV-1 acquisition and pathogenesis, and the relationship between these effects and the dose of MPA, are critical issues for women's health and access to suitable and safe contraceptives. We show for the first time that MPA, unlike NET, significantly increases HIV-1 replication in peripheral blood mononuclear cells (PBMCs) and a cervical cell line model. The results provide novel evidence for a biological mechanism whereby MPA, acting via the glucocorticoid receptor (GR), increases HIV-1 replication by at least in part increasing expression of the CCR5 HIV-1 coreceptor on target T-lymphocytes. MPA, unlike NET, also increases activation of T-cells and increases the CD4/CD8 ratio, suggesting that multiple mechanisms are involved in the MPA response. Our data offer strong support for different biological mechanisms for MPA versus NET, due to their differential GR activity. The dose-dependence of the MPA response suggests that significant effects are observed within the range of peak serum levels of progestins in DMPA-IM but not NET-EN users. Dose-response results further suggest that effects of contraceptives containing MPA on HIV-1 acquisition and disease progression may be critically dependent on dose, time after injection and intrinsic factors that affect serum concentrations in women.


Asunto(s)
VIH-1/fisiología , Acetato de Medroxiprogesterona/farmacología , Receptores CCR5/metabolismo , Receptores de Glucocorticoides/metabolismo , Replicación Viral/efectos de los fármacos , Antígenos CD4/genética , Antígenos CD4/metabolismo , Relación CD4-CD8 , Línea Celular , Femenino , Células HEK293 , VIH-1/efectos de los fármacos , Humanos , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/virología , Mifepristona/farmacología , Noretindrona/farmacología , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Receptores CCR5/genética , Receptores de Glucocorticoides/antagonistas & inhibidores , Receptores de Glucocorticoides/genética , Linfocitos T/citología , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo , Regulación hacia Arriba/efectos de los fármacos
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