INTRODUCTION: Diabetes mellitus (DM) and associated comorbidities correspond to female infertility by many interrelated mechanisms. Yet most prior research focuses only on ovary dysfunction. Our work evaluates literature mechanisms of DM-induced uterine tube and endometrial dysfunction, corresponding impacts on female fertility, and potential evidence-based intervention targets. METHODS: We conducted a scoping review (mapping review) follows the Joanna Briggs Institute (Manual for Evidence Synthesis, 2020 version). After identifying the research questions, we conducted a comprehensive search across four electronic databases by entering the keyword "diabetes", with a combination with other keywords as the uterus, endometrium, uterine/Fallopian tube, infertility and embryo implantation. We excluded manuscripts that address the issue of gestational diabetes. Most of these studies were in animals. RESULTS: There is compelling evidence for connecting DM with uterine tube infertility via endometriosis, thyroid dysfunction, and susceptibility to infectious disease. DM damages the endometrium before pregnancy via glucose toxicity, lesions, excessive immune activity, and other mechanisms. DM also hinders endometrium receptivity and embryo-endometrium crosstalk, such as through disrupted endometrium glucose homeostasis. We also hypothesize how DM may affect the function of immune cells in uterine tube and uterus, including changes in the number and types of cells of innate and acquired immunity, disrupting immunological barrier in uterine tube, alterations in formation of neutrophil extracellular traps or polarization of macrophages. DISCUSSION: We discuss evidence for clinical practice in terms of glycaemic control, lifestyle modifications, and medical interventions. For example, there is currently substantial evidence from rodent models for using metformin for increase in endometrial thickness, number of stromal cells and blood vessels and restoration of normal endometrial architecture, and bariatric surgery for recruitment of protective immune cell types to the endometrium. We also briefly highlight the future prospects of stem cells, artificial intelligence, and other new approaches for managing DM-associated female infertility. Further studies are necessary for optimizing female reproductive outcomes.

• Keywords
• diabetes mellitus, embryo-endometrium crosstalk, endometrial immune cell, endometrial receptivity, hyperglycaemia, hypothyroidism, infertility, tubal infertility,
• Publication type
• Journal Article MeSH
• Review MeSH

The uterine tube, as well as other parts of the upper female reproductive system, is immunologically unique in its requirements for tolerance to allogenic sperm and semi-allogenic embryos, yet responds to an array of sexually transmitted pathogens. To understand this dichotomy, there is a need to understand the functional morphology of immune cells in the wall of the uterine tube. Thus, we reviewed scientific literature regarding immune cells and the human uterine tube by using the scientific databases. The human uterine tube has a diverse population of immunocompetent cells representing both the innate and adaptive immune systems. We describe in detail the possible roles of cells of the mononuclear phagocyte system (macrophages and dendritic cells), T and B lymphocytes, natural killer cells, neutrophils and mast cells in association with the reproductive functions of uterine tubes. We are also discussing about the possible "immune privilege" of the uterine tube, as another mechanism to tolerate sperm and embryo without eliciting an inflammatory immune response. In uterine tube is not present an anatomical blood-tissue barrier between antigens and circulation. However, the immune cells of the uterine tube probably represent a type of "immunological barrier," which probably includes the uterine tube among the immunologically privileged organs. Understanding how immune cells in the female reproductive tract play roles in reproduction is essential to understand not only the mechanisms of gamete transport and fertilization as well as embryo transport through the uterine tube, but also in improving results from assisted reproduction.

• Keywords
• B lymphocyte, T lymphocyte, dendritic cell, fertility, macrophage, mast cell, natural killer cell, uterine tube,
• Publication type
• Journal Article MeSH
• Review MeSH

The uterine tube (UT) pathologies account for 25-35% of female factor infertility. Although these peculiar organs were first studied several hundred years ago, they have become overlooked and neglected mainly due to the successes of reproductive medicine. Nevertheless, the reproductive medicine still faces many challenges regarding the fertility outcomes of in vitro fertilization (IVF). Many obstacles and problems can be resolved by a more detailed understanding of the UT morphology and function during normal reproduction. Over the course of the 21st century, many new insights have been obtained: the presence of a population of telocytes in the tubal wall responsible for normal motility and hormone sensory function, the demonstration of lymphatic lacunae of the mucosal folds necessary for oocyte capture and tubal fluid recirculation, or a thorough profiling of the immune makeup of the UT epithelial lining with the discovery of regulatory T cells presumably important for maternal tolerance towards the semi-allogenic embryo. New discoveries also include the notion that the UT epithelium is male sex hormone-sensitive, and that the UT is not sterile, but harbors a complex microbiome. The UT epithelial cells were also shown to be the cells-of-origin of high-grade serous ovarian carcinomas. Finally, yet importantly, several modern morphological directions have been emerging recently, including cell culture, development of tubal organoids, in silico modelling, tissue engineering and regenerative medicine. All these novel insights and new approaches can contribute to better clinical practice and successful pregnancy outcomes.

• MeSH
• Epithelium MeSH
• Fertility * MeSH
• Fertilization in Vitro MeSH
• Humans MeSH
• Ovary MeSH
• Pregnancy MeSH
• Fallopian Tubes * pathology   MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Pregnancy MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

This article summarizes the importance of the exact morphology of human uterine/fallopian tube epithelium at the scanning electron microscopy (SEM) level for the clinical outcome even nowadays. Visual referential micrographs from SEM reflect two ways to view human epithelial cell lining surfaces: the surface epithelial uterine tube from surgical tissue biopsy and human fallopian tube epithelial cells (HFTEC) culture monolayer surface. One colorized image visualizes ciliated cells, distinguishes them from non-ciliated cells, and provides an educational benefit. A detailed description of the ultrastructure in referential and pathologic human uterine tube epithelium is important in defining the morphological basis of high-grade carcinomas, in the mechanism of pathophysiology, and in discussing options for its prevention. Cell cultures of human fallopian tube epithelial cells offer new approaches in simulating the mechanisms of cancer genesis or may help to elucidate the genetic basis of several diagnoses. New technical approaches in SEM provide higher resolution and detailed surface images. The SEM modality is still one of the current options in diagnostics and may be useful for advancing human reproductive organ cancer research.

• MeSH
• Biopsy MeSH
• Cell Culture Techniques MeSH
• Electrons * MeSH
• Epithelium MeSH
• Epithelial Cells MeSH
• Humans MeSH
• Microscopy, Electron, Scanning MeSH
• Fallopian Tubes * pathology   physiology   MeSH
• Check Tag
• Humans MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

Uterine tubes (UTs) are essential during physiological reproduction. The most intriguing part of its wall is the mucosa. Apart from the epithelial cells vital for its normal function, the connective tissue lamina propria contains wide spaces whose function, morphology and structure are yet to be elucidated. The present study used bioptic samples from 25 premenopausal (mean age 48,33 years, ?=3,56) and 25 postmenopausal women (mean age 57,8 years, ?=7,79). In both study groups, samples were obtained from two anatomically distinct parts of the UT - ampulla and infundibulum with fimbriae. The specimens were processed for scanning electron microscopy (SEM) and immunohistochemical detection of podoplanin (clone D2-40) and VEGFR-3 - two markers of lymphatic endothelial cells. The results showed that specimens from premenopausal and postmenopausal women contain wide lymphatic spaces, also known as lymphatic lacunae. The most probable function of the lacunae in the fimbriae is oocyte pick-up upon ovulation thanks to their ability to get engorged with lymph, thus serving as an erectile-like tissue. The ampullary lacunae are probably responsible for tubal fluid maintenance and recirculation. These results indicate that they are vital for normal reproduction because tubal fluid dynamics are as important as fluid composition. Further research on this topic is highly warranted because more detailed insights into UT function have a great potential to refine the methods of reproductive medicine, e.g. in vitro fertilization (IVF), which are still far from optimal regarding fertility outcomes.

• MeSH
• Electrons MeSH
• Endothelial Cells * MeSH
• Humans MeSH
• Microscopy, Electron, Scanning MeSH
• Mucous Membrane MeSH
• Fallopian Tubes * physiology   ultrastructure   MeSH
• Check Tag
• Humans MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

Microorganisms and eukaryotic human cells coexist in synergistic relationships in nearly every niche of the human body. The female genital tract consisting of the vagina, uterus with its cervix and endometrium, uterine tubes and ovaries - harbors its own typical microbiota, which accounts for 9 % of the total bacterial population in females. To this organ system, we also assigned the microbiome of the placenta, which has not been studied much until now. Among the spectrum of microbial species, the female genital tract is mainly dominated by Lactobacillus species, which are considered to be one of the simplest yet most important microbial communities. However, this relationship between macro- and micro-organisms seems to have a number of physiological functions, e.g., the vaginal and cervical microbiota have unique impact on reproductive health. The aim of this review was to provide current view on female genital tract microbiota and its role in reproductive health. We describe in detail the association of vaginal or tubal epithelium with microbiota or the role of microbiota in normal placental function.

• MeSH
• Humans MeSH
• Microbiota * physiology   MeSH
• Placenta MeSH
• Pregnancy MeSH
• Vagina microbiology   MeSH
• Fallopian Tubes * microbiology   MeSH
• Genitalia, Female MeSH
• Check Tag
• Humans MeSH
• Pregnancy MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Review MeSH

It is well known that the mammalian uterine tube (UT) plays a crucial role in female fertility, where the most important events leading to successful fertilization and pre-implantation embryo development occur. The known functions of these small intra-abdominal organs are: an uptake and transport of oocytes; storage, transportation, and capacitation of spermatozoa, and finally fertilization and transport of the fertilized ovum and early embryo through the isthmus towards the uterotubal junction. The success of all these events depends on the interaction between the uterine tube epithelium (UTE) and gametes/embryo. Besides that, contemporary research revealed that the tubal epithelium provides essential nutritional support and the most suitable environment for early embryo development. Moreover, recent discoveries in molecular biology help understand the role of the epithelium at the cellular and molecular levels, highlighting the factors involved in regulating the UT signaling, that affects different steps in the fertilization process. According to the latest research, the extracellular vesicles, as a major component of tubal secretion, mediate the interaction between gametes/embryo and epithelium. This review aims to provide up-to-date knowledge on various aspects concerning tubal epithelium activity and its cross-talk with spermatozoa, oocytes and preimplantation embryo and how these interactions affect fertilization and early embryo development.

• MeSH
• Epithelium MeSH
• Fertilization physiology   MeSH
• Humans MeSH
• Oocytes MeSH
• Reproduction * MeSH
• Mammals MeSH
• Spermatozoa physiology   MeSH
• Fallopian Tubes * physiology   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Review MeSH