RESUMEN
The peripheral T cell repertoire of healthy individuals contains self-reactive T cells1,2. Checkpoint receptors such as PD-1 are thought to enable the induction of peripheral tolerance by deletion or anergy of self-reactive CD8 T cells3-10. However, this model is challenged by the high frequency of immune-related adverse events in patients with cancer who have been treated with checkpoint inhibitors11. Here we developed a mouse model in which skin-specific expression of T cell antigens in the epidermis caused local infiltration of antigen-specific CD8 T cells with an effector gene-expression profile. In this setting, PD-1 enabled the maintenance of skin tolerance by preventing tissue-infiltrating antigen-specific effector CD8 T cells from (1) acquiring a fully functional, pathogenic differentiation state, (2) secreting significant amounts of effector molecules, and (3) gaining access to epidermal antigen-expressing cells. In the absence of PD-1, epidermal antigen-expressing cells were eliminated by antigen-specific CD8 T cells, resulting in local pathology. Transcriptomic analysis of skin biopsies from two patients with cutaneous lichenoid immune-related adverse events showed the presence of clonally expanded effector CD8 T cells in both lesional and non-lesional skin. Thus, our data support a model of peripheral T cell tolerance in which PD-1 allows antigen-specific effector CD8 T cells to co-exist with antigen-expressing cells in tissues without immunopathology.
Asunto(s)
Antígenos , Linfocitos T CD8-positivos , Tolerancia Inmunológica , Receptor de Muerte Celular Programada 1 , Piel , Animales , Humanos , Ratones , Antígenos/inmunología , Biopsia , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/patología , Epidermis/inmunología , Epidermis/metabolismo , Perfilación de la Expresión Génica , Liquen Plano/inmunología , Liquen Plano/patología , Receptor de Muerte Celular Programada 1/inmunología , Receptor de Muerte Celular Programada 1/metabolismo , Piel/citología , Piel/inmunología , Piel/metabolismo , Piel/patologíaRESUMEN
Bone marrow-derived progenitor cells (BMDPCs) are mobilized to the circulation in pregnancy and get recruited to the pregnant decidua where they contribute functionally to decidualization and successful implantation. However, the molecular mechanisms underlying BMDPCs recruitment to the decidua are unknown. CXCL12 ligand and its CXCR4 receptor play crucial roles in the mobilization and homing of stem/progenitor cells to various tissues. To investigate the role of CXCL12-CXCR4 axis in BMDPCs recruitment to decidua, we created transgenic GFP mice harboring CXCR4 gene susceptible to tamoxifen-inducible Cre-mediated ablation. These mice served as BM donors into wild-type C57BL/6 J female recipients using a 5-fluorouracil-based nongonadotoxic submyeloablation to achieve BM-specific CXCR4 knockout (CXCR4KO). Successful CXCR4 ablation was confirmed by RT-PCR and in vitro cell migration assays. Flow cytometry and immunohistochemistry showed a significant increase in GFP+ BM-derived cells (BMDCs) in the implantation site as compared to the nonpregnant uterus of control (2.7-fold) and CXCR4KO (1.8-fold) mice. This increase was uterus-specific and was not observed in other organs. This pregnancy-induced increase occurred in both hematopoietic (CD45+) and nonhematopoietic (CD45-) uterine BMDCs in control mice. In contrast, in CXCR4KO mice there was no increase in nonhematopoietic BMDCs in the pregnant uterus. Moreover, decidual recruitment of myeloid cells but not NK cells was diminished by BM CXCR4 deletion. Immunofluorescence showed the presence of nonhematopoietic GFP+ cells that were negative for CD45 (panleukocyte) and DBA (NK) markers in control but not CXCR4KO decidua. In conclusion, we report that CXCR4 expression in nonhematopoietic BMDPCs is essential for their recruitment to the pregnant decidua.
Asunto(s)
Células de la Médula Ósea , Receptores CXCR4 , Útero , Animales , Células de la Médula Ósea/fisiología , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Femenino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Transgénicos , Embarazo , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Útero/metabolismoRESUMEN
Hyperactivation of the CXCL12-CXCR4 axis occurs in endometriosis; the therapeutic potential of treatments aimed at global inhibition of the axis was recently reported. Because CXCR4 is predominantly expressed on epithelial cells in the uterus, this study explored the effects of targeted disruption of CXCR4 in endometriosis lesions. Uteri derived from adult female mice homozygous for a floxed allele of CXCR4 and co-expressing Cre recombinase under control of progesterone receptor promoter were sutured onto the peritoneum of cycling host mice expressing the green fluorescent protein. Four weeks after endometriosis induction, significantly lower number of lesions developed in Cxcr4-conditional knockout lesions relative to those in controls (37.5% vs. 68.8%, respectively). In lesions that developed in Cxcr4-knockout, reduced epithelial proliferation was associated with a lower ratio of epithelial to total lesion area compared with controls. Furthermore, while CD3+ lymphocytes were largely excluded from the epithelial compartment in control lesions, in Cxcr4-knockout lesions, CD3+ lymphocytes infiltrated the Cxcr4-deficient epithelium in the diestrus and proestrus stages. Current data demonstrate that local CXCR4 expression is necessary for proliferation of the epithelial compartment of endometriosis lesions, that its downregulation compromises lesion numbers, and suggest a role for epithelial CXCR4 in lesion immune evasion.
Asunto(s)
Endometriosis/inmunología , Endometriosis/metabolismo , Linfocitos Intraepiteliales/inmunología , Receptores CXCR4/metabolismo , Animales , Proliferación Celular , Células Epiteliales/inmunología , Femenino , RatonesRESUMEN
Decidua is a transient uterine tissue shared by mammals with hemochorial placenta and is essential for pregnancy. The decidua is infiltrated by many immune cells promoting pregnancy. Adult bone marrow (BM)-derived cells (BMDCs) differentiate into rare populations of nonhematopoietic endometrial cells in the uterus. However, whether adult BMDCs become nonhematopoietic decidual cells and contribute functionally to pregnancy is unknown. Here, we show that pregnancy mobilizes mesenchymal stem cells (MSCs) to the circulation and that pregnancy induces considerable adult BMDCs recruitment to decidua, where some differentiate into nonhematopoietic prolactin-expressing decidual cells. To explore the functional importance of nonhematopoietic BMDCs to pregnancy, we used Homeobox a11 (Hoxa11)-deficient mice, having endometrial stromal-specific defects precluding decidualization and successful pregnancy. Hoxa11 expression in BM is restricted to nonhematopoietic cells. BM transplant (BMT) from wild-type (WT) to Hoxa11-/- mice results in stromal expansion, gland formation, and marked decidualization otherwise absent in Hoxa11-/- mice. Moreover, in Hoxa11+/- mice, which have increased pregnancy losses, BMT from WT donors leads to normalized uterine expression of numerous decidualization-related genes and rescue of pregnancy loss. Collectively, these findings reveal that adult BMDCs have a previously unrecognized nonhematopoietic physiologic contribution to decidual stroma, thereby playing important roles in decidualization and pregnancy.
Asunto(s)
Células de la Médula Ósea/fisiología , Decidua/citología , Implantación del Embrión , Células Madre Mesenquimatosas/fisiología , Embarazo/fisiología , Animales , Femenino , Proteínas de Homeodominio/genética , Masculino , Ratones NoqueadosRESUMEN
Adult stem cells have a major role in endometrial physiology, including remodelling and repair. However, they also have a critical role in the development and progression of endometriosis. Bone marrow-derived stem cells engraft eutopic endometrium and endometriotic lesions, differentiating to both stromal and epithelial cell fates. Using a mouse bone marrow transplantation model, we show that bone marrow-derived cells engrafting endometriosis express CXCR4 and CXCR7. Targeting either receptor by the administration of small molecule receptor antagonists AMD3100 or CCX771, respectively, reduced BM-derived stem cell recruitment into endometriosis implants. Endometriosis lesion size was decreased compared to vehicle controls after treatment with each antagonist in both an early growth and established lesion treatment model. Endometriosis lesion size was not effected when the local effects of CXCL12 were abrogated using uterine-specific CXCL12 null mice, suggesting an effect primarily on bone marrow cell migration rather than a direct endometrial effect. Antagonist treatment also decreased hallmarks of endometriosis physiopathology such as pro-inflammatory cytokine production and vascularization. CXCR4 and CXCR7 antagonists are potential novel, non-hormonal therapies for endometriosis.
Asunto(s)
Bencilaminas/farmacología , Células de la Médula Ósea/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Ciclamas/farmacología , Endometriosis/tratamiento farmacológico , Endometrio/efectos de los fármacos , Receptores CXCR4/antagonistas & inhibidores , Receptores CXCR/antagonistas & inhibidores , Células Madre Adultas/efectos de los fármacos , Células Madre Adultas/metabolismo , Animales , Células de la Médula Ósea/metabolismo , Trasplante de Médula Ósea/métodos , Endometriosis/metabolismo , Endometrio/metabolismo , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal/efectos de los fármacos , Útero/efectos de los fármacos , Útero/metabolismoRESUMEN
Endometriosis is characterized by extrauterine growth of endometrial tissue accompanied by adverse clinical manifestations including chronic pelvic pain and infertility. Retrograde menstruation, the efflux of endometrium into the peritoneal cavity during menstruation, is believed to contribute to implantation of endometrial tissue and formation of endometriotic lesions at ectopic sites. While it is established through various rodent and nonhuman primate models that endometrial tissue fragments, as well as nondissociated stroma and glands, are capable of seeding endometriosis in a manner mimicking retrograde menstruation, the ability of single endometrial cells to participate in endometriotic processes has not been evaluated due to their failure to establish macroscopic endometriosis. We designed a model by which this capacity can be assessed by examining the integration of individual uterine cells into existing endometriosis lesions in mice. Endometriosis was induced in C57BL/6J female mice followed by intraperitoneal injection of GFP-labeled single uterine cells. We found that freshly introduced uterine cells can successfully integrate and contribute to various cell populations within the lesion. Strikingly, these cells also appeared to contribute to neo-angiogenesis and inflammatory processes within the lesion, which are commonly thought of as host-driven phenomena. Our findings underscore the potential of individual uterine cells to continuously expand lesions and participate in the progression of endometriosis. This model of retrograde menstruation may therefore be used to study processes involved in the pathophysiology of endometriosis.
Asunto(s)
Endometriosis/etiología , Endometrio/citología , Trastornos de la Menstruación/complicaciones , Animales , Modelos Animales de Enfermedad , Endometriosis/patología , Femenino , Ratones , Ratones Endogámicos C57BLRESUMEN
Endometriosis is ectopic growth of endometrial tissue traditionally thought to arise through retrograde menstruation. We aimed to determine if cells derived from endometriosis could enter vascular circulation and lead to hematogenous dissemination. Experimental endometriosis was established by transplanting endometrial tissue from DsRed+ mice into the peritoneal cavity of DsRed- mice. Using flow cytometry, we identified DsRed+ cells in blood of animals with endometriosis. The circulating donor cells expressed CXCR4 and mesenchymal stem cell (MSC) biomarkers, but not hematopoietic stem cell markers. Nearly all the circulating endometrial stem cells originated from endometriosis rather than from the uterus. Cells expressing DsRed, CXCR4, and MSCs markers were identified in the peritoneal wall and surrounding vessels of recipient mice, contributing to both endometriosis and angiogenesis. Cells originating in endometriosis lesions migrated and implanted in lung tissue and displayed makers of differentiation, indicating retained multipotency. In vitro these cells demonstrated multipotency and were able to differentiate into adipogenic, osteogenic, and chondrogenic lineages. Endometriosis lesions also expressed high levels of CXCL12, the CXCR4 receptor ligand. Serum CXCL12 levels were greater than in sham control mice. In humans with endometriosis, serum CXCL12 levels were significantly higher than controls, suggesting that the CXCL12/CXCR4 axis is operational in women with spontaneous endometriosis as well. Stem cells, rather than differentiated cells from endometriosis, enter the circulation in response to CXCL12. We identify an endometriosis-derived stem cell population, a potential mechanism of dissemination of this disease and a potential target for treatment of endometriosis. Stem Cells 2018;36:881-890.
Asunto(s)
Endometriosis/metabolismo , Células Madre Mesenquimatosas/metabolismo , Adulto , Animales , Diferenciación Celular , Modelos Animales de Enfermedad , Endometriosis/patología , Femenino , Humanos , Ratones , Persona de Mediana Edad , Transducción de Señal , Adulto JovenRESUMEN
STUDY QUESTION: Is diminished functional ovarian reserve (DFOR) associated with low androgen levels? SUMMARY ANSWER: Low androgen levels are associated with DFOR at all ages. WHAT IS KNOWN ALREADY: Androgen supplementation via dehydroepiandrosterone (DHEA) has been reported to improve functional ovarian reserve (FOR); pregnancy rates in IVF cycles are associated with how well DHEA converts to testosterone (T); and androgen effects through the androgen receptor have been demonstrated in mice to beneficially affect early stages of follicle maturation. STUDY DESIGN, SIZE, DURATION: In a controlled cohort study we investigated consecutive women presenting to our center with two forms of DFOR, premature ovarian aging/occult primary ovarian insufficiency (POA/OPOI) and physiologic diminished ovarian reserve (DOR). As controls for POA/OPOI patients, infertile women with normal age-specific FOR were recruited. PARTICIPANTS/MATERIALS, SETTINGS, METHODS: The study involved 140 women with POA/OPOI, defined as age <38 years and abnormally low FOR by age-specific FSH and/or anti-Müllerian hormone (AMH), 166 women with DOR, defined as women age >40 years. Forty-nine control patients <38 years demonstrated normal FOR by FSH and/or AMH. In all three patient groups dehydroepiandrosterone (DHEA), DHEA-sulfate (DHEAS), total testosterone (TT) and free testosterone (FT) at the time of initial presentation to our fertility center were assessed. In a small subgroup of women early morning cortisol levels were also assessed. MAIN RESULTS AND THE ROLE OF CHANCE: DHEAS marginally varied between the three groups (P = 0.04), with older women with DOR actually demonstrating higher levels than controls (P = 0.03). TT differed between the three groups more profoundly (P = 0.005), with women with POA/OPOI demonstrating significantly lower levels than controls (P = 0.009). Adjustment for body mass index, age and race in principle maintained observed differences in TT between groups, while adjustment for FMR1 (fragile X mental retardation 1) genotypes/sub-genotypes eliminated all differences. All three patient groups demonstrated low morning cortisol levels. LIMITATIONS, REASONS FOR CAUTION: While results support lower androgen levels in women with DOR, and even more so in women with POA/OPOI, presented data should be viewed as preliminary, considering the known variability of androgen levels and the small number of women in whom morning cortisol levels were available. WIDER IMPLICATIONS OF THE FINDINGS: Especially at young ages DFOR appears associated with significant hypoandrogenism (low T) in comparison with young control patients with normal FOR, raising the question whether this hypoandrogenism originates in adrenals or ovaries. POA/OPOI, thus, phenotypically mimics the polycystic ovary syndrome, where similar questions arise, though in regard to hyperandrogenism. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by the Foundation for Reproductive Medicine, a not-for-profit medical research foundation and intramural funds from the Center for Human Reproduction. N.G. and D.H.B are members of the Board of the Foundation for Reproductive Medicine. N.G., A.W. and D.H.B. received research support, lecture fees and travel support from a variety of pharmaceutical and medical device companies, none in any way related to the issues discussed in this manuscript. N.G. and D.H.B. are listed as co-inventors on two, already granted US user patents, which claim therapeutic benefits from DHEA supplementation in women with DFOR and DOR: both authors are also listed on additional pending patents in regard to DHEA supplementation and on pending patents, claiming diagnostic and therapeutic benefits from the determination of CGG repeats on the FMR1 gene. N.G. is the owner of the Center for Human Reproduction, where this research was performed.
Asunto(s)
Andrógenos/sangre , Hormona Antimülleriana/sangre , Ovario/fisiología , Adulto , Factores de Edad , Estudios de Cohortes , Deshidroepiandrosterona/sangre , Sulfato de Deshidroepiandrosterona/sangre , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Hidrocortisona/sangre , Testosterona/sangreRESUMEN
BACKGROUND: Hypothesizing that redundant functional ovarian reserve (FOR) at young ages may clinically obfuscate prematurely diminished FOR (PDFOR), we investigated in young oocyte donors genotypes and sub-genotypes of the FMR1 gene, in prior studies associated with specific ovarian aging patterns, and determined whether they already at such young age were associated with variations in ovarian reserve (OR). We also investigated racial as well as FMR1 associations with menarcheal age in these donors. METHODS: In a cohort study we investigated 157 oocyte donor candidates and, based on the 95% CI of AMH, divided them into normal age-specific (AMH greater or equal to 2.1 ng/mL; n = 121) and PDFOR (AMH < 2.1 ng/mL; n = 36). We then assessed associations between numbers of trinucleotide repeat (CGGn) on the FMR1 gene and FOR (based on anti-Müllerian hormone, AMH). RESULTS: FMR1 did not associate with AMH overall. Amongst 36 donors with PDFOR, 17 (42%) presented with at least one low (CGGn < 26 ) allele. Remaining donors with normal FOR presented with significantly more CGGn greater or equal to 26 (73.6% vs. 26.4%; P = 0.024) and higher AMH (P = 0.012). This finding was mostly the consequence of interaction between FMR1 (CGGn < 26 vs. CGGn greater or equal to 26) and race (P = 0.013), with Asians most responsible (P = 0.009). Menarcheal age was in donors with normal FOR neither associated with race nor with FMR1 status. In donors with PDFOR race was statistically associated with CGGn (P = 0.018), an association primarily based on significantly delayed age of menarche in African donors with CGGn < 26 in comparison to African donors with CGGn greater or equal to 26 (P = 0.019), and Caucasian (P = 0.017) and Asian donors (P = 0.025) with CGGn < 26. CONCLUSIONS: CGGn on FMR1 already at young ages affects FOR, but is clinically apparent only in cases of PDFOR. Screening for low FMR1 CGGn < 26 at young age, thus, appears predictive of later PDFOR.
Asunto(s)
Envejecimiento/genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/fisiología , Donación de Oocito , Ovario/crecimiento & desarrollo , Adulto , Hormona Antimülleriana/sangre , Pueblo Asiatico , Población Negra , Estudios de Cohortes , Etnicidad , Femenino , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Genotipo , Humanos , Población Blanca , Adulto JovenRESUMEN
BACKGROUND: Low functional ovarian reserve (FOR) is at all ages associated with low testosterone (T) levels. Causes are, however, unknown. We, therefore, investigate whether androgens with low FOR are associated with non-specific immune system activation. METHODS: 322 infertile women with low and normal FOR (controls) were assessed with a broadly based immune profile, which in previous studies has proven effective in differentiating infertile patients with and without immune system activation. Patients were either immune-positive (greater than or equal to one positive tested parameter) or immune negative (no positive test). 135 suffered from prematurely diminished FOR (POA/OPOI; < age 38), 155 from physiologic diminished FOR due to age (DOR; > age 40), and 32 were controls (< age 38 with normal age-specific FOR). Prevalence of immune-positive vs. negative was assessed in all 3 patient groups. RESULTS: Women with immune abnormalities, overall, demonstrated higher total T (TT, P = 0.004) and free T (FT, P < 0.001) levels than those without. The three clinical and two immunologic-defined patient groups demonstrated significant statistical interaction in mean TT (P = 0.008), with mean TT and FT in women with positive immune findings being significantly higher in control than in POA/OPOI and physiologic DOR patients (all 4 differences P < 0.001). No such differences between the three groups were seen in women without immune abnormalities. CONCLUSIONS: In this study we used a definition of immune-positivity, which favors sensitivity over specificity, resulting in significant numbers of false-positives but likely only few false-negatives. The study allows suggesting the possibility of an immune system-derived androgen-production factor (APF), which maintains normal androgen levels but is deficient in women with low FOR and immune system inactivity. Existence of such an APF would suggest the presence of a still unknown functional adrenal autoimmune system.
Asunto(s)
Glándulas Suprarrenales/inmunología , Autoinmunidad/inmunología , Sistema Inmunológico/inmunología , Ovario/inmunología , Testosterona/sangre , Adulto , Análisis de Varianza , Andrógenos/sangre , Autoanticuerpos/sangre , Índice de Masa Corporal , Femenino , Humanos , Infertilidad Femenina/sangre , Infertilidad Femenina/inmunología , Persona de Mediana EdadRESUMEN
PURPOSE: To investigate whether androgen conversion rates after supplementation with dehydroepiandrosterone (DHEA) differ, and whether differences between patients with diminished ovarian reserve (DOR) are predictive of pregnancy chances in association with in vitro fertilization (IVF). METHODS: In a prospective cohort study we investigated 213 women with DOR, stratified for age (≤ 38 or >38 years) and ovarian FMR1 genotypes/sub-genotypes. All women were for at least 6 weeks supplemented with 75 mg of DHEA daily prior to IVF, between initial presentation and start of 1st IVF cycles. Levels of DHEA, DHEA-sulfate (DHEAS), total T (TT) and free T (FT) at baseline ((BL)) and IVF cycle start ((CS)) were then compared between conception and non-conception cycles. RESULTS: Mean age for the study population was 41.5 ± 4.4 years. Forty-seven IVF cycles (22.1 %) resulted in clinical pregnancy. Benefits of DHEA on pregnancy rates were statistically associated with efficiency of androgen conversion from DHEA to T and amplitude of T gain. Younger women converted significantly more efficiently than older females, and selected FMR1 genotypes/sub-genotypes converted better than others. FSH/androgen and AMH/androgen ratios represent promising new predictors of IVF pregnancy chances in women with DOR. CONCLUSIONS: DOR at all ages appears to represent an androgen-deficient state, benefitting from androgen supplementation. Efficacy of androgen supplementation with DHEA, however, varies depending on female age and FMR1 genotype/sub-genotype. Further clarification of FMR1 effects should lead to better individualization of androgen supplementation, whether via DHEA or other androgenic compounds.
Asunto(s)
Andrógenos/administración & dosificación , Infertilidad Femenina/terapia , Ovario/metabolismo , Índice de Embarazo , Testosterona/sangre , Adulto , Factores de Edad , Andrógenos/deficiencia , Hormona Antimülleriana/sangre , Deshidroepiandrosterona/administración & dosificación , Deshidroepiandrosterona/sangre , Femenino , Fertilización In Vitro/métodos , Hormona Folículo Estimulante/sangre , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Genotipo , Humanos , Infertilidad Femenina/diagnóstico , Modelos Logísticos , Ciclo Menstrual , Persona de Mediana Edad , Ovario/efectos de los fármacos , Inducción de la Ovulación/métodos , Valor Predictivo de las Pruebas , Embarazo , Estudios Prospectivos , Resultado del TratamientoRESUMEN
CXCR4 is a key regulator of the development of NK cells and DCs, both of which play an important role in early placental development and immune tolerance at the maternal-fetal interface. However, the role of CXCR4 in pregnancy is not well understood. Our study demonstrates that adult-induced global genetic CXCR4 deletion, but not uterine-specific CXCR4 deletion, was associated with increased pregnancy resorptions and decreased litter size. CXCR4-deficient mice had decreased NK cells and increased granulocytes in the decidua, along with increased leukocyte numbers in peripheral blood. We found that CXCR4-deficient mice had abnormal decidual NK cell aggregates and NK cell infiltration into trophoblast areas beyond the giant cell layer. This was associated with low NK cell expression of granzyme B, a NK cell granule effector, indicative of NK cell dysfunction. Pregnancy failure in these mice was associated with abnormalities in placental vascular development and increased placental expression of inflammatory genes. Importantly, adoptive BM transfer of WT CXCR4+ BM cells into CXCR4-deficient mice rescued the reproductive deficits by normalizing NK cell function and mediating normal placental vascular development. Collectively, our study found an important role for maternal CXCR4 expression in immune cell function, placental development, and pregnancy maintenance.
Asunto(s)
Decidua , Placenta , Animales , Femenino , Ratones , Embarazo , Placentación/genética , Transducción de Señal/fisiología , Trofoblastos/metabolismoRESUMEN
The integrity of mitosis is dependent upon strict regulation of microtubule stability and dynamics. Although much information has been accumulated on regulators of the microtubule cytoskeleton, our knowledge of the specific pathways involved is still limited. Here we designed genetic screens to identify regulators of microtubule stability that are dispensable in the wild type yet become essential under microtubule-disrupting conditions. We found that the transcriptional cofactor Swi6p and activator Swi4p, as well as the G(2)/M-specific cyclin Clb2p, are required in a microtubule-destabilizing environment. Swi6p and Swi4p can combine as a transcriptional complex, called the SBF complex (SBF for Swi4/6 cell cycle box [SCB]-binding factor) that is functionally homologous to the metazoan DP1/2-E2F complex and that controls the G(1)/S transition through the genes it regulates. We show that Swi6p's contribution to microtubule stability can be either dependent or independent of the SBF complex. The SBF-dependent pathway requires downregulation of SBF complex levels and may thereby reroute the transcriptional program in favor of greater microtubule stability. This pathway can be triggered by overexpression of Fcp1p, a phosphatase in the general transcription machinery, or by expression of an allele of SWI6 that is associated with reduced transcription from SBF-controlled promoters. The SBF-independent pathway is activated by a constitutively nuclear allele of Swi6p. Our results introduce novel roles in microtubule stability for genes whose participation in the process may be masked under normal conditions yet nonetheless acquire a dominant role when microtubule stability is compromised.
Asunto(s)
Ciclina B/metabolismo , Proteínas de Unión al ADN/metabolismo , Microtúbulos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/metabolismo , Secuencias de Aminoácidos , Ciclina B/genética , Proteínas de Unión al ADN/genética , Técnicas de Inactivación de Genes , Cinesinas/genética , Proteínas Asociadas a Microtúbulos/genética , Microtúbulos/efectos de los fármacos , Mitosis , Proteínas Motoras Moleculares/genética , Complejos Multiproteicos/metabolismo , Fenotipo , Fosfoproteínas Fosfatasas/química , Fosfoproteínas Fosfatasas/genética , Fosfoproteínas Fosfatasas/metabolismo , Estabilidad Proteica , Saccharomyces cerevisiae/crecimiento & desarrollo , Proteínas de Saccharomyces cerevisiae/genética , Tiabendazol/farmacología , Factores de Transcripción/genética , Moduladores de Tubulina/farmacologíaRESUMEN
Girls with obesity are at increased risk of early puberty. Obesity is associated with insulin resistance and hyperinsulinemia. We hypothesized that insulin plays a physiological role in pubertal transition, and super-imposed hyperinsulinemia due to childhood obesity promotes early initiation of puberty in girls. To isolate the effect of hyperinsulinemia from adiposity, we compared pre-pubertal and pubertal states in hyperinsulinemic, lean muscle (M)-insulin-like growth factor 1 receptor (IGF-1R)-lysine (K)-arginine (R) (MKR) mice to normoinsulinemic WT, with puberty onset defined by vaginal opening (VO). Our results show MKR had greater insulin resistance and higher insulin levels (P < 0.05) than WT despite lower body weight (P < 0.0001) and similar IGF-1 levels (P = NS). Serum luteinizing hormone (LH) levels were higher in hyperinsulinemic MKR (P = 0.005), and insulin stimulation induced an increase in LH levels in WT. VO was earlier in hyperinsulinemic MKR vs WT (P < 0.0001). When compared on the day of VO, kisspeptin expression was higher in hyperinsulinemic MKR vs WT (P < 0.05), and gonadotropin-releasing hormone and insulin receptor isoform expression was similar (P = NS). Despite accelerated VO, MKR had delayed, disordered ovarian follicle and mammary gland development. In conclusion, we found that hyperinsulinemia alone without adiposity triggers earlier puberty. In our study, hyperinsulinemia also promoted dyssynchrony between pubertal initiation and progression, urging future studies in girls with obesity to assess alterations in transition to adulthood.
Asunto(s)
Hiperinsulinismo , Resistencia a la Insulina , Obesidad Infantil , Animales , Femenino , Humanos , Hiperinsulinismo/metabolismo , Insulina , Ratones , Pubertad/fisiologíaRESUMEN
Hematopoietic stem and progenitor cells (HSPCs) tightly couple maintenance of the bone marrow (BM) reservoir, including undifferentiated long-term repopulating hematopoietic stem cells (LT-HSCs), with intensive daily production of mature leukocytes and blood replenishment. We found two daily peaks of BM HSPC activity that are initiated by onset of light and darkness providing this coupling. Both peaks follow transient elevation of BM norepinephrine and TNF secretion, which temporarily increase HSPC reactive oxygen species (ROS) levels. Light-induced norepinephrine and TNF secretion augments HSPC differentiation and increases vascular permeability to replenish the blood. In contrast, darkness-induced TNF increases melatonin secretion to drive renewal of HSPCs and LT-HSC potential through modulating surface CD150 and c-Kit expression, increasing COX-2/αSMA+ macrophages, diminishing vascular permeability, and reducing HSPC ROS levels. These findings reveal that light- and darkness-induced daily bursts of norepinephrine, TNF, and melatonin within the BM are essential for synchronized mature blood cell production and HSPC pool repopulation.
Asunto(s)
Diferenciación Celular/efectos de la radiación , Oscuridad , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/efectos de la radiación , Luz , Animales , Células Cultivadas , Epigénesis Genética/genética , Células Madre Hematopoyéticas/metabolismo , Ratones , Ratones Endogámicos C57BL , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
Importance: Sexual dysfunction, an important determinant of women's health and quality of life, is commonly associated with declining estrogen levels around the menopausal transition. Objective: To determine the effects of oral or transdermal estrogen therapy vs placebo on sexual function in postmenopausal women. Design, Setting, and Participants: Ancillary study of the Kronos Early Estrogen Prevention Study (KEEPS), a 4-year prospective, randomized, double-blinded, placebo-controlled trial of menopausal hormone therapy in healthy, recently menopausal women. Of 727 KEEPS enrollees, 670 agreed to participate in this multicenter ancillary study. Women were 42 to 58 years old, within 36 months from last menstrual period. Data were collected from July 2005 through June 2008 and analyzed from July 2010 through June 2017. Interventions: Women were randomized to either 0.45 mg/d oral conjugated equine estrogens (o-CEE), 50 µg/d transdermal 17ß-estradiol (t-E2), or placebo. Participants also received 200 mg oral micronized progesterone (if randomized to o-CEE or t-E2) or placebo (if randomized to placebo estrogens) for 12 days each month. Main Outcomes and Measures: Aspects of sexual function and experience (desire, arousal, lubrication, orgasm, satisfaction, and pain) were assessed using the Female Sexual Function Inventory (FSFI; range, 0-36 points; higher scores indicate better sexual function). Low sexual function (LSF) was defined as an FSFI overall score of less than 26.55. Distress related to low FSFI score (required for the diagnosis of sexual dysfunction) was not evaluated. Results: The 670 participants had a mean (SD) age of 52.7 (2.6) years. The t-E2 treatment was associated with a significant yet moderate improvement in the FSFI overall score across all time points compared with placebo (average efficacy, 2.6; 95% CI, 1.11-4.10; adjusted P = .002). With o-CEE treatment, there was no significant difference in FSFI overall score compared with placebo (mean efficacy, 1.4; 95% CI, -0.1 to 2.8; adjusted P = .13). There was no difference in FSFI overall score between the t-E2 and o-CEE groups on average across 48 months (adjusted P = .22). In the individual domains of sexual function, t-E2 treatment was associated with a significant increase in mean lubrication (0.61; 95% CI, 0.25-0.97; P = .001) and decreased pain (0.67; 95% CI, 0.25-1.09; P = .002) compared with placebo. Overall, the proportion of women with LSF was significantly lower after t-E2 treatment compared with placebo (67%; 95% CI, 55%-77% vs 76%; 95% CI, 67%-83%; P = .04). For o-CEE there was no significant reduction in the odds of LSF. Conclusions and Relevance: Treatment with t-E2 modestly improved sexual function in early postmenopausal women, but whether it relieved symptoms of distress is not known. Trial Registration: clinicaltrials.gov Identifier: NCT00154180.
Asunto(s)
Terapia de Reemplazo de Estrógeno/métodos , Estrógenos Conjugados (USP)/administración & dosificación , Posmenopausia , Calidad de Vida , Disfunciones Sexuales Fisiológicas/tratamiento farmacológico , Administración Cutánea , Administración Oral , Adulto , Método Doble Ciego , Estradiol/administración & dosificación , Estradiol/análogos & derivados , Estrógenos/administración & dosificación , Femenino , Estudios de Seguimiento , Glucuronatos/administración & dosificación , Humanos , Persona de Mediana Edad , Progesterona/administración & dosificación , Progestinas/administración & dosificación , Estudios Prospectivos , Escalas de Valoración Psiquiátrica , Factores de Riesgo , Disfunciones Sexuales Fisiológicas/psicología , Factores de Tiempo , Salud de la MujerRESUMEN
Rescue in vitro maturation (IVM) is currently not a routine procedure in association with in vitro fertilization (IVF). We compared in a prospectively cohort study of 10 patients with normal functional ovarian reserve (NFOR) and of 25 with low functional ovarian reserve (LFOR), defined by abnormally high FSH and/or abnormally low AMH levels), IVM dynamics of immature oocytes. Following controlled ovarian hyperstimulation in IVF cycles, only immature oocytes underwent rescue IVM (for up to 48 h). Oocyte maturation dynamics, fertilization rates, embryo development, and pregnancy rates were then compared between NFOR and LFOR patients. Though proportion of MI and GV oocytes reaching MII stages within 48 h and rate of maturation of MI oocytes did not differ, in women with LFOR significantly more GV oocytes reached MII stage within 24 h (30.4 vs. 66.9 %; P = 0.013), while fertilization rates and embryo generation numbers were similar between both groups. Rescue IVM, thus, produced 1.5 additional embryos for transfer in women with LFOR and 1.6 in patients with NFOR, a highly significant difference in relative improvement in available embryo numbers for LFOR (+60.0 %) and NFOR women (+16.5 %). Rescue IVM, thus, not only demonstrates different time dynamics between women with LFOR and NFOR but also disproportionate efficacy in improving available embryo numbers for transfer in favor of LFOR patients. 1/7 patients, who reached embryo transfer with only embryos produced via rescue IVF conceived and delivered, proving that rescue IVF in women with LFOR also improves pregnancy and delivery chances. Because of the small number of embryos LFOR patients produce, every additional embryo is of considerable potential clinical significance for them, suggesting that rescue IVM in women with LFOR should become routine practice.
Asunto(s)
Técnicas de Maduración In Vitro de los Oocitos/métodos , Enfermedades del Ovario/patología , Reserva Ovárica , Adulto , Estudios de Cohortes , Transferencia de Embrión/métodos , Desarrollo Embrionario , Femenino , Fertilización In Vitro , Hormona Folículo Estimulante/sangre , Humanos , Infertilidad Femenina , Ciclo Menstrual , Recuperación del Oocito , Inducción de la Ovulación , Embarazo , Estudios ProspectivosRESUMEN
Hypoandrogenism in women with low functional ovarian reserve (LFOR, defined as an abnormally low number of small growing follicles) adversely affects fertility. The androgen precursor dehydroepiandrosterone (DHEA) is increasingly used to supplement treatment protocols in women with LFOR undergoing in vitro fertilization. Due to differences in androgen metabolism, however, responses to DHEA supplementation vary between patients. In addition to overall declines in steroidogenic capacity with advancing age, genetic factors, which result in altered expression or enzymatic function of key steroidogenic proteins or their upstream regulators, might further exacerbate variations in the conversion of DHEA to testosterone. In this Review, we discuss in vitro studies and animal models of polymorphisms and gene mutations that affect the conversion of DHEA to testosterone and attempt to elucidate how these variations affect female hormone profiles. We also discuss treatment options that modulate levels of testosterone by targeting the expression of steroidogenic genes. Common variants in genes encoding DHEA sulphotransferase, aromatase, steroid 5α-reductase, androgen receptor, sex-hormone binding globulin, fragile X mental retardation protein and breast cancer type 1 susceptibility protein have been implicated in androgen metabolism and, therefore, can affect levels of androgens in women. Short of screening for all potential genetic variants, hormonal assessments of patients with low testosterone levels after DHEA supplementation facilitate identification of underlying genetic defects. The genetic predisposition of patients can then be used to design individualized fertility treatments.
Asunto(s)
Andrógenos/deficiencia , Deshidroepiandrosterona/metabolismo , Infertilidad Femenina/genética , Testosterona/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/genética , Animales , Aromatasa/genética , Deshidroepiandrosterona/uso terapéutico , Modelos Animales de Enfermedad , Femenino , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Genes BRCA1 , Humanos , Reserva Ovárica , Polimorfismo Genético , Receptores Androgénicos/genética , Globulina de Unión a Hormona Sexual/genética , Sulfotransferasas/genéticaRESUMEN
OBJECTIVE: To investigate whether granulocyte colony-stimulating factor (G-CSG) affects endometrial thickness, implantation rates, and clinical pregnancy rates in routine, unselected IVF cycles. DESIGN: Registered, individually randomized, two-group, parallel double-blinded placebo-controlled clinical trial. SETTING: Academically affiliated private clinical and research center. PATIENT(S): 141 consecutive, unselected, consenting women with no history of renal disease, sickle cell disease, or malignancy who were undergoing IVF. INTERVENTION(S): Sealed, numbered, opaque envelopes assigned 73 patients to receive G-CSF (Filgrastim, Amgen, 300 µg/1.0 mL) and 68 to receive placebo (saline). MAIN OUTCOME MEASURE(S): Endometrial thickness, clinical pregnancy, and embryo implantation rates. RESULT(S): The mean age for the whole study group was 39.59 ± 5.56 years (G-CSF: 39.79 ± 5.13 years; placebo: 39.38 ± 6.03 years). Endometrial thickness statistically significantly increased over the 5-day observation period for the whole group by approximately 1.36 mm. The increase in the G-CSF group was not statistically significantly different from the control group. Statistical models looking at treatment effects on clinical pregnancy and implantation rates demonstrated no effect of G-CSF treatment. There were no adverse events for either treatment group. CONCLUSION(S): In normal IVF patients, G-CSF does not affect endometrial thickness, implantation rates, or clinical pregnancy rates. Because these results were obtained in an older patient population, they may not necessarily apply to younger women. CLINICAL TRIAL REGISTRATION NUMBER: NCT01202656.
Asunto(s)
Endometrio/efectos de los fármacos , Fertilización In Vitro/métodos , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Perfusión/métodos , Índice de Embarazo , Adulto , Estudios Cruzados , Método Doble Ciego , Endometrio/patología , Endometrio/fisiología , Femenino , Fertilización In Vitro/tendencias , Humanos , Persona de Mediana Edad , Embarazo , Resultado del Embarazo/epidemiología , Índice de Embarazo/tendenciasRESUMEN
CONTEXT: Mutations of the fragile X mental retardation 1 (FMR1) gene are associated with distinct ovarian aging patterns. OBJECTIVE: To confirm in human in vitro fertilization (IVF) that FMR1 affects outcomes, and to determine whether this reflects differences in ovarian aging between FMR1 mutations, egg/embryo quality or an effect on implantation. DESIGN, SETTING, PATIENTS: IVF outcomes were investigated in a private infertility center in reference to patients' FMR1 mutations based on a normal range of CGG(nâ=â26-34) and sub-genotypes high (CGG(n>34)) and low (CGG(<26)). The study included 3 distinct sections and study populations: (i) A generalized mixed-effects model of morphology (777 embryos, 168 IVF cycles, 125 infertile women at all ages) investigated whether embryo quality is associated with FMR1; (ii) 1041 embryos in 149 IVF cycles in presumed fertile women assessed whether the FMR1 gene is associated with aneuploidy; (iii) 352 infertile patients (< age 38; in 1st IVF cycles) and 179 donor-recipient cycles, assessed whether the FMR1 gene affects IVF pregnancy chances via oocyte/embryo quality or non-oocyte maternal factors. INTERVENTIONS: Standardized IVF protocols. MAIN OUTCOME MEASURES: Morphologic embryo quality, ploidy and pregnancy rates. RESULTS: (i) Embryo morphology was reduced in presence of a low FMR1 allele (Pâ=â0.032). In absence of a low allele, the odds ratio (OR) of chance of good (vs. fair/poor) embryos was 1.637. (ii) FMR1 was not associated with aneuploidy, though aneuploidy increased with female age. (iii) Recipient pregnancy rates were neither associated with donor age or donor FMR1. In absence of a low FMR1 allele, OR of clinical pregnancy (vs. chemical or no pregnancy) was 2.244 in middle-aged infertility patients. CONCLUSIONS: A low FMR1 allele (CGG(<26)) is associated with significantly poorer morphologic embryo quality and pregnancy chance. As women age, low FMR1 alleles affect IVF pregnancy chances by reducing egg/embryo quality by mechanisms other than embryo aneuploidy.