TGF-β1 Neutralization Improves Pregnancy Outcomes by Restoring Endometrial Receptivity in Mice with Adenomyosis

Analysis of cumulative live birth rate outcomes of four ovarian stimulation protocols in Poseidon groups 3/4 patients with adenomyosis

PURPOSE

To compare the effects of the gonadotrophin-releasing hormone (GnRH) agonist protocol, GnRH antagonist protocol, progestin-primed ovarian stimulation (PPOS) protocol, and mild stimulation/natural cycle protocol on the cumulative live birth rate (CLBR) in patients with adenomyosis and Poseidon group 3/4.

METHODS

A total of 1090 patients diagnosed with adenomyosis and Poseidon groups 3/4 group who underwent in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) from January 2013 to December 2020 were included. Demographic characteristics, laboratory indicators, and clinical outcomes of the four ovarian stimulation protocols were compared. The primary outcome was the CLBR, with binary logistic regression analysis used to explore the factors influencing CLBR.

RESULTS

Among the patients with adenomyosis and Poseidon groups 3/4, the CLBR in GnRH agonist protocol group was higher than that in PPOS protocol group (45.78% vs. 22.33%, P = 0.005). Binary logistic regression analysis revealed that GnRH agonist protocol had a higher CLBR compared to PPOS protocol (adjusted odds ratio (aOR) 3.26, 95% confidence interval (CI): 1.56-6.83, P = 0.002), while no significant differences were found when comparing PPOS protocol with GnRH antagonist protocol (P = 0.093) and mild stimulation/natural cycle protocol (P = 0.125). In the < 35 years subgroup, the CLBR of GnRH agonist protocol was significantly higher (55.26% vs. 33.82%; P = 0.032), which wasn't observed in elder subgroups (P > 0.05).

CONCLUSION

For patients with both adenomyosis and Poseidon groups 3/4, GnRH agonist protocol showed a higher CLBR, especially in patients < 35 years (Poseidon group 3).

Adenomyosis-associated infertility: an update of the immunological perspective

Adenomyosis is characterized by the invasion of endometrial glands and stroma into the myometrium. Its clinical manifestations often include dysmenorrhoea, excessive menstrual bleeding and infertility. Reduced pregnancy and live birth rates and an increased miscarriage rate are observed in women with adenomyosis. This review summarizes relevant advances and presents the underlying mechanisms of adenomyosis-associated infertility from an immunological perspective. Individuals with adenomyosis exhibit imbalances in immune cell subpopulations and the endocrine hormone-immunomodulatory axis. These immunological alterations may be key contributors to, or at least accomplices in, impaired endometrial receptivity. In addition, adenomyosis often occurs in association with endometriosis, uterine leiomyoma or endometrial polyps, which are pathogenetically relevant; their similarities and differences are discussed from an immunological perspective. The clinical diagnostic criteria of adenomyosis are not perfect, and the pathogenesis remains to be fully explored. Therefore screening for effective targets for early diagnosis and treatment at the cellular and molecular levels from the immunological point of view holds great potential, which will be of great importance in preventing this disease and improving women's reproductive health.

The Involvement of Mitochondrial Dysfunction during the Development of Adenomyosis

The etiology of adenomyosis remains unclear. The association between epithelial-mesenchymal transition (EMT) and mitochondrial dysfunction is involved in fibrotic diseases. Adenomyosis is defined as the existence of endometrial glands and stroma in the myometrium with EMT and ultimate fibrosis. This study was designed to investigate the involvement of mitochondrial dysfunction in fibrotic adenomyosis. Mitochondrial integrity was examined in mouse and human adenomyotic tissues. Control and tamoxifen-treated mice were treated with 3-nitropropionic acid (a mitochondrial dysfunction inducer) and NG-nitro-L-arginine methyl ester (a mitochondrial dysfunction inhibitor), respectively, at postnatal day 21, followed by an evaluation of adenomyosis, EMT, and fibrosis as well as the expression of mitophagy, oxidative stress, and transforming growth factor-β1 (TGF-β1). The gene profiles of adenomyotic uteri were examined at postnatal day 42. Adenomyotic mice exhibited increased development of EMT and fibrosis. Adenomyotic tissues showed consistent mitochondrial destruction with increased fission, mitophagosomes, and lysosomes. Besides, mitophagy, oxidative stress, and TGF-β1 levels were consistently increased. The mitochondrial dysfunction, the development of mitophagy and fibrosis, and TGF-β1 expression were induced by 3-nitropropionic acid in control uteri. In contrast, NG-nitro-L-arginine methyl ester attenuated mitochondrial dysfunction, mitophagy, fibrosis, and TGF-β1 in adenomyotic uteri. Gene profiling demonstrated increased expression of mitochondrial dysfunction-related genes in adenomyotic uteri. This indicates that mitochondrial dysfunction-induced TGF-β1 dysregulation and fibrosis are associated with the development of adenomyosis.

Impaired fertility and perinatal outcomes in adenomyosis: insights from a novel murine model and uterine gene profile alterations during implantations

BACKGROUND

Adenomyosis is a uterine disorder closely linked to infertility and adverse pregnancy outcomes. Despite its clinical significance, the mechanisms by which adenomyosis impairs embryo implantation and perinatal outcomes remain incompletely defined. Previous studies have indicated that alterations in the uterine microenvironment may contribute to these reproductive challenges.

OBJECTIVE

To investigate the effects of adenomyosis on fertility and perinatal outcomes using a novel murine model and to identify molecular pathways involved in implantation failure and pregnancy loss.

STUDY DESIGN

A mechanically induced adenomyosis model was established in female Bagg Albino/c mice through endometrial-myometrial interface disruption to closely simulate the clinical condition observed in humans. Mice were randomly assigned to either the adenomyosis group or a sham-operated control group. Reproductive outcomes were systematically assessed at multiple gestational time points, focusing on embryo implantation site distribution, implantation rates, pregnancy loss, fetal growth parameters, and postnatal uterine recovery. In parallel, uterine tissues collected from implantation sites and interimplantation regions at 4.5 days postcoitus were subjected to RNA sequencing. Differential gene expression analyses were performed, and enriched pathways were identified using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment tools.

RESULTS

Mice in the adenomyosis group demonstrated significant disruptions in the uterine microenvironment compared to controls. Notably, the adenomyosis group exhibited irregular distribution of implantation sites with reduced interembryo distances, leading to compromised spatial organization of the developing conceptuses. Although the total number of embryos at early gestation did not differ significantly between groups, a marked increase in pregnancy loss was observed during mid-gestation, accompanied by a reduction in the size of surviving embryos. Histological evaluation revealed extensive architectural disruptions in the uterine muscle layers and increased local inflammatory responses in adenomyotic uteri. RNA sequencing further revealed that adenomyosis was associated with the dysregulation of multiple genes involved in immune modulation, apoptotic regulation, and metabolic processes. In particular, significant enrichment of the phosphoinositide 3-kinase-Akt pathway, mitogen-activated protein kinase, and tumor necrosis factor signaling pathways was observed, suggesting that variation in these cascades may underlie the impaired uterine receptivity and embryo development seen in adenomyosis.

CONCLUSION

Our findings indicate that adenomyosis exerts a adverse effect on fertility and perinatal outcomes by disrupting the uterine environment and interfering with critical molecular pathways essential for proper embryo implantation and development. The results of this study not only enhance our understanding of adenomyosis pathophysiology but also pinpoint potential molecular targets-such as the phosphoinositide 3-kinase-Akt pathway, mitogen-activated protein kinase, and tumor necrosis factor pathways-for therapeutic intervention. These insights offer promising targets for developing treatments aimed at reversing the adverse reproductive impacts associated with adenomyosis.

Uterine Collagen Cross-Linking: Biology, Role in Disorders, and Therapeutic Implications

Collagen is an essential constituent of the uterine extracellular matrix that provides biomechanical strength, resilience, structural integrity, and the tensile properties necessary for the normal functioning of the uterus. Cross-linking is a fundamental step in collagen biosynthesis and is critical for its normal biophysical properties. This step occurs enzymatically via lysyl oxidase (LOX) or non-enzymatically with the production of advanced glycation end-products (AGEs). Cross-links found in uterine tissue include the reducible dehydro-dihydroxylysinonorleucine (deH-DHLNL), dehydro-hydroxylysinonorleucine (deH-HLNL), and histidinohydroxymerodesmosine (HHMD); and the non-reducible pyridinoline (PYD), deoxy-pyridinoline (DPD); and a trace of pentosidine (PEN). Collagen cross-links are instrumental for uterine tissue integrity and the continuation of a healthy pregnancy. Decreased cervical cross-link density is observed in preterm birth, whereas increased tissue stiffness caused by increased cross-link density is a pathogenic feature of uterine fibroids. AGEs disrupt embryo development, decidualization, implantation, and trophoblast invasion. Uterine collagen cross-linking regulators include steroid hormones, such as progesterone and estrogen, prostaglandins, proteoglycans, metalloproteinases, lysyl oxidases, nitric oxide, nicotine, and vitamin D. Thus, uterine collagen cross-linking presents an opportunity to design therapeutic targets and warrants further investigation in common uterine disorders, such as uterine fibroids, cervical insufficiency, preterm birth, dystocia, endometriosis, and adenomyosis.

Reduced fertility in an adenomyosis mouse model is associated with an altered immune profile in the uterus during the implantation period

STUDY QUESTION

Does a reduction in fertility and/or systemic immune cell change occur during the early implantation period in a mouse model of adenomyosis?

SUMMARY ANSWER

A reduction in fertility was observed in mice with adenomyosis, coinciding with local and systemic immune changes observed during the implantation period.

WHAT IS KNOWN ALREADY

Adenomyosis is a pathology responsible for impaired fertility in humans, with a still unclear pathophysiology. One hypothesis is that changes in immune cells observed in adenomyosis-affected uteri may alter fertility, notably the physiological immune environment necessary for successful implantation and a healthy pregnancy.

STUDY DESIGN, SIZE, DURATION

Randomly selected CD-1 female neonatal pups were orally dosed by administration of tamoxifen to induce adenomyosis (TAM group), while others received solvent only (control group). From 6 weeks of life, CD-1 mice of both groups were mated to study impaired fertility and related local and/or systemic immune cell changes during the early implantation period.

PARTICIPANTS/MATERIALS, SETTINGS, METHODS

To evaluate fertility and pregnancy outcomes, ultrasound imaging was performed at E (embryonic day) 7.5 and E11.5 to count the number of gestational sacs and the number of resorptions in eight mice of the TAM group and 16 mice of the control group. The mice were sacrificed at E18.5, and morphometric, functional (quantitative reverse transcription PCR; RT-qPCR), and histological analyses were performed on the placentas. To identify local and/or systemic immune changes during the early implantation period, 8 mice of the TAM group and 12 mice of the control group were sacrificed at E4.5. Uterine horns and spleens were collected for flow cytometry and RT-qPCR analyses to study the immune cell populations. To investigate the profile of the cytokines secreted during the early implantation period at the systemic level, supernatants from stimulated spleen cells were analyzed by multiplex immunoassay analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

By ultrasound imaging, we observed a lower number of implantation sites (P < 0.005) and a higher number of resorptions (P < 0.001) in the TAM group, leading to smaller litters (average number of fetuses per litter: 1.00 [0.00; 5.25] in the TAM group versus 12.00 [9.50; 13.75] in the control group (P < 0.001). Histological and morphometric analyses of the placentas at E18.5 showed a higher junctional/labyrinthine area ratio in the TAM group (P = 0.005). The expression levels of genes that play a role in vascularization and placental growth (Vegf (P < 0.001), Plgf (P < 0.005), Pecam (P < 0.0001), and Igf2 (P = 0.002)) were reduced in the TAM group. In the TAM group, the percentages of macrophages, natural killer (NK) cells, and dendritic cells (DC) were significantly decreased in the uterus around the implantation period. However, the number of M1 macrophages was increased. Both macrophages and DC had an increased activation profile (higher expression of MCHII, P = 0.012; CD80, P = 0.015; CCR7, P = 0.043 for macrophages, and higher expression of CD206, P = 0.018; CXCR4, P = 0.010; CCR7, P = 0.006, MCHII, P = 0.010; and CD80, P = 0.012 for DC). In spleen, an increase in the activation of macrophages (CCR7, P = 0.002; MCHII, P = 0.001; and CD80, P = 0.034) and DC was observed in the TAM group (CCR7, P = 0.001; MCHII, P = 0.001; Ly6C, P = 0.015). In the uteri and the spleen, we observed increased percentages of CD4+ T lymphocytes (P = 0.0237 and P = 0.0136, respectively) in the TAM group and, in the uteri, an increased number of regulatory T cells (P = 0.036) compared with the controls.

LARGE SCALE DATA

Not applicable.

LIMITATIONS, REASONS FOR CAUTION

This study is limited by the use of an animal model and the lack of intervention.

WIDER IMPLICATIONS OF THE FINDINGS

These data support involvement of innate and adaptive immune cells in the implantation failure and the increased rate of resorption observed in the mouse model of adenomyosis. This substantiates the need for additional research in this domain, with the goal of addressing fertility challenges in women affected by this condition.

STUDY FUNDING/COMPETING INTEREST(S)

None.

Molecular Targets for Nonhormonal Treatment Based on a Multistep Process of Adenomyosis Development

Adenomyosis is an estrogen-dependent gynecologic disease characterized by the presence of endometrial tissue within the myometrium. Adenomyosis presents with abnormal uterine bleeding, pelvic pains, and infertility. This review aimed to investigate the major estrogen downstream effectors involved in the process of adenomyosis development and their potential use for nonhormonal treatment. A literature search was performed for preclinical and clinical studies published between January 2010 and November 2021 in the PubMed and Google Scholar databases using a combination of specific terms. Adenomyosis presents with a wide spectrum of clinical manifestations from asymptomatic to severe through a complex process involving a series of molecular changes associated with inflammation, invasion, angiogenesis, and fibrosis. Adenomyosis may develop through a multistep process, including the acquisition of (epi)genetic mutations, tissue injury caused at the endometrial-myometrial interface, inside-to-outside invasion (from the endometrial side into the uterine wall), or outside-to-inside invasion (from the serosal side into the uterine wall), and epithelial-mesenchymal transition, tissue repair or remodeling in the myometrium. These processes can be regulated by increased estrogen biosynthesis and progesterone resistance. The expression of estrogen downstream effectors associated with persistent inflammation, fragile and more permeable vessel formation, and tissue injury and remodeling may be correlated with dysmenorrhea, heavy menstrual bleeding, and infertility, respectively. Key estrogen downstream targets (e.g., WNT/β-catenin, transforming growth factor-β, and nuclear factor-κB) may serve as hub genes. We reviewed the molecular mechanisms underlying the development of adenomyosis and summarized potential nonhormonal therapies.

Endometrial Inflammation and Impaired Spontaneous Decidualization: Insights into the Pathogenesis of Adenomyosis

Adenomyosis is an estrogen-dependent gynecologic disease characterized by the myometrial invasion of the endometrial tissue. This review summarized the current understanding and recent findings on the pathophysiology of adenomyosis, focusing on repeated menstruation, persistent inflammation, and impaired spontaneous decidualization. A literature search was performed in the PubMed and Google Scholar databases from inception to 30 April 2022. Thirty-one full-text articles met the eligibility criteria. Repeated episodes of physiological events (i.e., endometrial shedding, damage, proliferation, differentiation, repair, and regeneration) during the menstrual cycle are associated with inflammation, angiogenesis, and immune processes. The decidualization process in humans is driven by the rise in progesterone levels, independently of pregnancy (i.e., spontaneous decidualization). Adenomyotic cells produce angiogenic and fibrogenic factors with the downregulation of decidualization-associated molecules. This decidualization dysfunction and persistent inflammation are closely related to the pathogenesis of adenomyosis. Recently, it has been found that the reproductive tract microbiota composition and function in women with adenomyosis differ from those without. An increase in opportunistic pathogens and a decrease in beneficial commensals may promote impaired defense mechanisms against inflammation and predispose women to uncontrolled endometrial inflammation. However, currently, there is no direct evidence that adenomyosis is linked to pre-existing inflammation and impaired spontaneous decidualization. Overall, persistent inflammation, impaired spontaneous decidualization, and microbiota dysbiosis (i.e., an imbalance in the composition and function of endometrial microbiota) may be involved in the pathophysiology of adenomyosis.

The Effect of Uterine Adenomyosis on IVF Outcomes: a Systematic Review and Meta-analysis

To investigate the impact of uterine adenomyosis on in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) clinical outcomes and also to evaluate the impact of gonadotropin-releasing hormone agonist (GnRHa) and surgical treatments. Infertile women with adenomyosis undergoing conventional IVF or ICSI were compared with women without adenomyosis. Fertility outcomes were evaluated in two patients with adenomyosis untreated and treated surgically or medically therapy. The review protocol was registered in PROSPERO (CRD42020214586). We consider the live birth rate (LBR) as the primary outcome. The analysis showed that women with adenomyosis had lower LBR (OR 0.59, 95% CI 0.37-0.92, p = 0.02), clinical pregnancy rate (OR 0.66, 95% CI 0.48-0.90), and ongoing pregnancy rate (OR 0.43, 95% CI 0.21-0.88) compared to those without adenomyosis, and miscarriage rate was higher in women with adenomyosis (OR 2.11, 95% CI 1.33-3.33). Surgical treatment increases natural conception in women with adenomyosis although the paucity of data (only two studies), and conversely, treatment with GnRHa does not increase the IVF outcomes. Women with adenomyosis have decreased IVF clinical outcomes. Pretreatment with the use of long-term GnRHa could not be beneficial, even though only three studies were included in the meta-analysis. The major part of the studies has not divided focal and diffuse adenomyosis, and this represents a relevant source of bias: studies conducted with standardized diagnostic criteria for adenomyosis are still needed to determine if the different clinical presentations of such condition could compromise IVF outcomes.

Circadian desynchronization in pregnancy of Golden hamster following long time light exposure: Involvement of Akt/FoxO1 pathway

Coordination between central and peripheral reproductive clocks in females is poorly understood. Long light is having a hazardous effect on reproductive health. Hence, explored the effect of long-time light exposure (LLD; 16L:8D) on the central and peripheral reproductive (ovary and uterus) clock genes (Bmal1, Clock, Per1, Per2, Cry1 and Cry2) and its downstream regulators (Aanat, Egf, Cx26, Cx43, ERα, pAktS-473, pAktT-308, pFoxO1T-24, 14-3-3, HoxA10, HoxA11 and Pibf) expression in non-pregnant and pregnant Golden hamster. Young adult Golden hamsters were exposed to LLD for 30 days and then were mated. We observed that LLD exposure increased the thickness of the endometrium and reduced myometrium thickness, resembling uterine adenomyosis. In non-pregnant females LLD altered the expressions of clock genes in suprachiasmatic nuclei (SCN), ovary and the uterus along with serum estradiol rhythm. LLD upregulated Egf and downregulated Aanat, Cx26, and Cx43 mRNA levels in uterus. LLD upregulated Akt/FoxO1 phosphorylation and 14-3-3 expressions in the uterus of nonpregnant females. LLD exposure to pregnant females lowered serum progesterone, Aanat, Pibf, Hoxa10, and Hoxa11 mRNA expressions on D4 (peri-implantation) and D8 (post-implantation) resulting in a low implantation rate on D8 (post-implantation). Hence it is evident that the frequent pregnancy anomalies noted under a long light schedule might be due to desynchronization in Aanat, Pibf, Hoxa10, and Hoxa11 as well as the central and peripheral clock genes (Bmal1, Clock, Per1, Per2, Cry1 and Cry2). LLD exposure desynchronized the central and peripheral reproductive clock affecting uterine physiology via Akt/FoxO1 pathway in Golden hamsters. Thus, LLD is a risk factor for female reproductive health and fertility.

Adenomyosis and fertility: does adenomyosis impact fertility and does treatment improve outcomes

PURPOSE OF REVIEW

Adenomyosis has recently been associated with infertility. Relief of bleeding and pain has been demonstrated with medical and surgical therapy. Less is known about reproductive outcomes after treatment.

RECENT FINDINGS

Imaging findings during infertility evaluation can be suggestive of adenomyosis without pathologic evaluation. Among women with infertility undergoing assisted reproductive technologies (ART), adenomyosis is associated with lower live birth rates and clinical pregnancy rates. Treatment with gonadotropin releasing hormone (GnRH) modulators prior to frozen embryo transfer may increase the live birth rate and clinical pregnancy rate among women with adenomyosis. Pregnancy has been documented following image-guided adenomyosis ablation; however, the reproductive impact is not well established. Pregnancy following excisional procedures appears to be well tolerated, although may carry a higher risk of uterine rupture compared with pregnancy following myomectomy. It is not clear if ablative therapy or resection increases pregnancy rates.

SUMMARY

Adenomyosis is associated with lower embryo implantation rates and ongoing pregnancy rates. Adenomyotic changes in the uterus can be seen by ultrasound and MRI. GnRH modulators may be useful for women with adenomyosis undergoing ART. Additional prospective data is warranted to determine the optimal medical or surgical therapy for women with adenomyosis desiring conception.Video abstract Supplementary digital content, http://links.lww.com/COOG/A78.