Genital epithelial barrier function is conserved by intravaginal rings releasing etonogestrel and ethinyl estradiol.

The injectable progestin depot-medroxyprogesterone acetate (DMPA) is a popular contraceptive choice in sub-Saharan Africa although mouse models indicate it weakens genital epithelial integrity and barrier function and increases susceptibility to genital infection. The intravaginal ring NuvaRing® is another contraceptive option that like DMPA suppresses hypothalamic pituitary ovarian (HPO) axis function with local release of progestin (etonogestrel) and estrogen (ethinyl estradiol). As we previously reported that treating mice with DMPA and estrogen averts the loss of genital epithelial integrity and barrier function induced by DMPA alone, in the current investigation we compared genital levels of the cell-cell adhesion molecule desmoglein-1 (DSG1) and genital epithelial permeability in rhesus macaques (RM) treated with DMPA or a NuvaRing®re-sized for RM (N-IVR). While these studies demonstrated comparable inhibition of the HPO axis with DMPA or N-IVR, DMPA induced significantly lower genital DSG1 levels and greater tissue permeability to intravaginally administered low molecular mass molecules. By identifying greater compromise of genital epithelial integrity and barrier function in RM administered DMPA vs. N-IVR, our results add to the growing body of evidence that indicate DMPA weakens a fundamental mechanism of anti-pathogen host defense in the female genital tract.

Loss of genital epithelial barrier function is greater with depot-medroxyprogesterone acetate than intravaginal rings that release etonogestrel and ethinyl estradiol.

The injectable progestin depot-medroxyprogesterone acetate (DMPA) is a popular contraceptive choice in sub-Saharan Africa although mouse models indicate it weakens genital epithelial integrity and barrier function and increases susceptibility to genital infection. The intravaginal ring NuvaRing® is another contraceptive option that like DMPA suppresses hypothalamic pituitary ovarian (HPO) axis function with local release of progestin (etonogestrel) and estrogen (ethinyl estradiol). As we previously reported that treating mice with DMPA and estrogen averts the loss of genital epithelial integrity and barrier function induced by DMPA alone, in the current investigation we compared genital levels of the cell-cell adhesion molecule desmoglein-1 (DSG1) and genital epithelial permeability in rhesus macaques (RM) treated with DMPA or a NuvaRing®re-sized for RM (N-IVR). While these studies demonstrated comparable inhibition of the HPO axis with DMPA or N-IVR, DMPA induced significantly lower genital DSG1 levels and greater tissue permeability to intravaginally administered low molecular mass molecules. By identifying greater compromise of genital epithelial integrity and barrier function in RM administered DMPA vs. N-IVR, our results add to the growing body of evidence that indicate DMPA weakens a fundamental mechanism of anti-pathogen host defense in the female genital tract.

Ovariectomized mice and postmenopausal women exhibit analogous loss of genital epithelial integrity.

Roughly half of all postmenopausal women are affected by the genitourinary syndrome of menopause (GSM). Symptoms of GSM, including vaginal irritation and dyspareunia, occur as reduced estrogen (E) production elicits loss of elasticity and other changes in genital tract tissue. While the use of the injectable contraceptive depot-medroxyprogesterone acetate (DMPA) likewise lowers serum E concentrations in reproductive age women and is associated with decreased genital levels of the cell-cell adhesion molecules desmoglein-1 (DSG1) and desmocollin-1 (DSC1) and impaired genital epithelial barrier function, the relevance of these findings to women in menopause is uncertain. Exploring the impact of menopause on genital epithelial integrity herein, we detected significantly lower levels of DSG1 and DSC1 in ectocervical tissue from menopausal and postmenopausal vs premenopausal women. Using ovariectomized (OVX) mice as a menopause model, we comparably saw significantly lower vaginal tissue levels of DSG1 and DSC1 in OVX mice vs. mice in estrus. Compared to estrus-stage mice and E-treated OVX mice, DMPA-treated ovary-intact mice and OVX mice also exhibited significantly reduced genital epithelial barrier function, greater susceptibility to genital herpes simplex virus type 2 infection, and delayed clearance of genital Chlamydia trachomatis infection. Current studies thus identify analogous loss of genital epithelial integrity in OVX mice and menopausal and postmenopausal women. By showing that loss of genital epithelial integrity is associated with increased mouse susceptibility to bacterial and viral pathogens, our findings also prioritize the need to resolve if reduced genital epithelial integrity in postmenopausal women is a significant risk factor for genital infection.

Exogenous sex steroids regulate genital epithelial barrier function in female rhesus macaques.

There is concern that using depot-medroxyprogesterone acetate (DMPA) for pregnancy prevention heightens HIV susceptibility. While no clinical data establishes causal link between HIV acquisition and use of this injectable progestin, prior work from our laboratory showed that DMPA comparably lowers genital levels of the cell-cell adhesion molecule desmoglein-1 (DSG1) and weakens genital epithelial barrier function in female mice and women. We likewise saw DMPA increase mouse susceptibility to multiple genital pathogens including HIV. Herein, we sought to confirm and extend these findings by comparing genital epithelial barrier function in untreated rhesus macaques (RM) vs. RM treated with DMPA or DMPA and estrogen (E). Compared to controls, genital tissue from RM with pharmacologically relevant serum levels of medroxyprogesterone acetate displayed significantly lower DSG1 levels and greater permeability to low molecular mass molecules. Conversely, DMPA-mediated effects on genital epithelial integrity and function were obviated in RM administered DMPA and E. These data corroborate the diminished genital epithelial barrier function observed in women initiating DMPA and identify RM as a useful preclinical model for defining effects of exogenous sex steroids on genital pathogen susceptibility. As treatment with E averted DMPA-mediated loss of genital epithelial barrier function, our results also imply that contraceptives releasing progestin and E may be less likely to promote transmission of HIV and other sexually transmitted pathogens than progestin-only compounds.

Norethisterone Enanthate Increases Mouse Susceptibility to Genital Infection with Herpes Simplex Virus Type 2 and HIV Type 1.

Norethisterone enanthate (NET-EN) and depot-medroxyprogesterone acetate (DMPA) are two forms of injectable progestin used for contraception. Whereas clinical research indicates that women using DMPA are more susceptible to HIV and other genital pathogens, causal relationships have not been determined. Providing an underlying mechanism for this connection, however, is recent work that showed DMPA weakens genital mucosal barrier function in mice and humans and respectively promotes susceptibility of wild-type and humanized mice to genital infection with HSV type 2 and HIV type 1. However, analogous effects of NET-EN treatment on antivirus immunity and host susceptibility to genital infection are much less explored. In this study, we show that compared with mice in estrus, treatment of mice with DMPA or NET-EN significantly decreased genital levels of the cell-cell adhesion molecule desmoglein-1 and increased genital mucosal permeability. These effects, however, were more pronounced in DMPA- versus NET-EN-treated mice. Likewise, we detected comparable mortality rates in DMPA- and NET-EN-treated wild-type and humanized mice after intravaginal infection with HSV type 2 or cell-associated HIV type 1, respectively, but NET-EN treatment was associated with slower onset of HSV-induced genital pathology and lower burden of systemic HIV disease. These findings reveal DMPA and NET-EN treatment of mice significantly reduces genital desmoglein-1 levels and increases genital mucosal permeability and susceptibility to genital pathogens while also implying that NET-EN generates less compromise of genital mucosal barrier function than DMPA.

Depot-medroxyprogesterone acetate reduces genital cell-cell adhesion molecule expression and increases genital herpes simplex virus type 2 infection susceptibility in a dose-dependent fashion.

OBJECTIVE: Analyzing ectocervical biopsy tissue from women before and after they initiated use of depot-medroxyprogesterone acetate (DMPA), we previously reported this progestin reduces levels of the cell-cell adhesion molecule (CCAM) desmoglein-1 and increases genital mucosal permeability. We likewise saw treating mice with 1.0 mg of DMPA reduced vaginal CCAM expression and increased genital pathogen susceptibility. Herein, we used dose-response studies to delimit DMPA doses and serum MPA levels in mice associated with impaired genital mucosal barrier function and enhanced susceptibility to low-dose herpes simplex virus type 2 (HSV-2) infection. STUDY DESIGN: We compared genital CCAM expression, genital mucosal permeability, and susceptibility to genital inoculation with 103 plaque-forming units of HSV-2 among mice in estrus vs. after treatment with 0.01 mg, 0.1 mg, 0.3 mg, or 1.0 mg of DMPA. RESULTS: Compared to mice in estrus, DMPA treatment in a dose-dependent fashion significantly reduced desmoglein 1α (Dsg1a) and desmocollin-1 (Dsc1) gene expression, reduced DSG1 protein levels, and increased genital mucosal permeability to a low molecular weight molecule. While no mice infected with HSV-2 in estrus died, we respectively saw 50% and 100% mortality in mice administered 0.1 mg or 0.3 mg of DMPA. At time of infection, mean serum MPA levels in mice administered the 0.1 mg or 0.3 mg doses were 3.8 nM and 13.0 nM respectively (values comparable to trough and peak MPA serum levels in women using DMPA). CONCLUSIONS: Mice with pharmacologically relevant serum MPA concentrations display significant changes in genital CCAM expression, genital mucosal barrier function, and HSV-2 susceptibility.