Histamine receptors in the female reproductive system. Part I. Role of the mast cells and histamine in female reproductive system

Histamine isolated from many different tissues, acts via three types of histamine receptors: H1, H2 and H3. In peripheral tissues histamine is mainly stored in mast cells (MC). Presence of mast cells was proved also in mammals' uteri. In human uterus the majority of mast cells are located close to smooth muscle cells. It might indicate that MC plays a role in tissue remodelling during the menstrual cycle. The quantity and activity of mast cells is in connection with hormonal status of the organism. Although there are some differences, human uterine mast cells are similar to the mast cells isolated from other tissues. It is suggested that histamine is important for normal ovulation, blastocyst implantation, placental blood flow regulation, lactation and contractile activity of uterus. Histamine may also play a role in pathological processes such as pre-eclampsia or preterm delivery. The participation of mast cells and histamine in blastocyst implantation is very controversial. In W/Wv mice (without mast cells) normal implantation was observed. It denies the main role of mast cells in this process but dos not exclude histamine action. In mice the major source of histamine are uterine epithelial cells during early pregnancy. The influence of cytokines on blastocyst implantation and the role of histamine in cytokines release from the uterine mast cells are also very unclear.     

Histamine receptors in the female reproductive system. Part II. The role of histamine in the placenta,histamine receptors and the uterus contractility

The presence of the mast cells was confirmed not only in the uterus but also in the placental tissue. Mediators released from the placental mast cells may play a role in regulation of placental blood flow and normal blood pressure. Processes such uptake and clearance of vasoactive mediators may be upset in those women who developed pre-eclampsia. Histamine released from the placental mast cells may be involved in the mechanisms controlling myometrium contractility during the labour at term and preterm delivery. There is a correlation between the level of placental histamine and presence (or not) uterus contractility. Histamine produce a contractile response in isolated myometrial strips, in the majority of mammals, via H1 histamine receptors activation, but in some species e.g. rat, predominant response of uterus is relaxation (via H2 histamine receptors activation). Predominant response of the human uterus to histamine is contraction. Relaxation of human myometrial strips may be evoked after earlier usage of H1 receptors antagonists, although some H2 receptors agonists (e.g. dimaprit) induce the relaxation of human uterus without H1 receptors antagonists. Myometrium contractile activity is under control of sexual hormones. Neither the presence of H3 histamine receptors on the human myometrial smooth cells nor its role in the female reproductive system regulation was proved. Lack of the functional H3 receptors either on the smooth muscle cells or neuronal components of the animals' myometrium was shown in some studies.     

Human testicular mast cells contain tryptase: increased mast cell number and altered distribution in the testes of infertile men

OBJECTIVE: To determine whether human testicular mast cells contain the potent fibroblast growth factor tryptase and to examine changes in mast cell morphology and intratesticular distribution in testes with normal spermatogenesis versus abnormal spermatogenesis. DESIGN: Retrospective evaluation of testicular biopsies with the use of immunohistochemistry, morphometry, and electron microscopy. SETTING: University research and clinical institutes. PATIENT(S): Infertile men (total of 24) with severe hypospermatogenesis, germ cell arrest syndrome, or Sertoli cell only syndrome, and men without pathologies. INTERVENTION(S): Diagnostic testicular biopsy. MAIN OUTCOME MEASURE(S): Location, number, and distribution of testicular mast cells. RESULT(S): All groups showed tryptase-positive mast cells. In specimens with normal spermatogenesis, mast cells were round and located mainly in the interstitial spaces close to Leydig cells. In germ cell arrest syndrome, a 2-fold increase was evident, and in Sertoli cell only syndrome, a >3-fold increase of tryptase-immunoreactive mast cells became evident. Moreover, there was a statistically significant shift of the cells from the interstitium to the tubular walls in Sertoli cell only syndrome and germ cell arrest syndrome. Mast cells in specimens of Sertoli cell only syndrome and germ cell arrest syndrome were heterogeneous, with rounded or elongated shapes and signs of degranulation. The thickness of the tubular walls was doubled in specimens of germ cell arrest syndrome and Sertoli cell only syndrome in comparison with normal specimens, and this increase was positively correlated with the number of mast cells in these patients. CONCLUSION(S): Our results suggest that mast cell products, including the potent fibroblast growth factor tryptase, are involved in the thickening of the tubular wall and other changes in infertile testes.     

Marked elevation of macrophage migration inhibitory factor in the peritoneal fluid of women with endometriosis

OBJECTIVE: To evaluate the presence of macrophage migration inhibitory factor (MIF) in the peritoneal fluid of normal fertile women and patients with endometriosis and its growth-promoting activity toward human endothelial cells. DESIGN: Retrospective study using ELISA to measure peritoneal fluid MIF, and [3H]-thymidine incorporation into the DNA of human endothelial cells to assess its mitogenic activity. SETTING: Gynecology clinic and human reproduction research laboratory. PATIENT(S): Thirty-six healthy women and 57 women with endometriosis. INTERVENTION(S): Peritoneal fluid samples were obtained at laparoscopy. MAIN OUTCOME MEASURE(S): Macrophage migration inhibitory factor concentrations in the peritoneal fluid samples and [3H]-thymidine incorporation into the DNA of human microvascular endothelial cells to assess proliferation. RESULT(S): This study demonstrated the presence of MIF in the peritoneal fluid and a 238% increase of MIF levels in women with endometriosis as compared with healthy women. Both fertile and infertile women with endometriosis had significantly higher MIF concentrations than did fertile women with normal gynecological status, but the difference was more significant in infertile endometriosis patients. Anti-MIF antibody significantly inhibited proliferation of human microvascular endothelial cells in response to peritoneal fluids from healthy women and women with endometriosis stages I-II and III-IV, as assessed by [3H]-thymidine incorporation. CONCLUSION(S): This study revealed the presence of MIF in the peritoneal fluid and its increased levels in endometriosis and suggests that MIF may be involved in endometriosis-associated infertility and angiogenesis.     

Production of interleukin-1-like molecules by human sperm cells

Objective: To characterize and localize interleukin (IL)-1 and IL-1β in human sperm cells.

Design: Prospective and comparative study.

Setting: Andrology clinic of a university hospital.

Patient(s): Two groups of normogonadotropic men: 17 fertile men (donors with proved fertility) and 8 oligoteratoasthenospermic infertile men.

Intervention(s): None.

Main Outcome Measure(s): Evaluation of IL-1 and IL-1β levels and expression in sperm cells by immunohistochemical staining, immunoassay, and Western blot analysis.

Result(s): Both types of IL-1–like molecules (IL-1 and IL-1β) were expressed in the tail, neck, and head of sperm cells of fertile men and patients with oligoteratoasthenospermia. Swim-up sperm cells from fertile men and patients with oligoteratoasthenospermia secreted similar levels of IL-1–like molecules. The levels of IL-1β–like molecules were higher than those of IL-1–like molecules in both groups. The expressed IL-1–like molecules were characterized by the presence a 60-kd protein for both IL-1–like and IL-1β–like molecules. In some samples of both fertile men and infertile men with oligoteratoasthenospermia, 17-kd, 33-kd, and 45-kd IL-1β–like molecules were detected. Impairment of sperm function, such as decreased sperm count and motility and/or impaired morphology, was not related to the capacity of sperm cells to produce IL-1–like molecules.

Conclusion(s): IL-1 molecules originating in sperm cells may play a role in the physiologic functions of sperm cells (autocrine effect) and/or in cell–cell interactions within the testis (paracrine effect).     

Expression of progesterone receptors is significantly impaired in the endometrium of infertile women during the implantation window: a prospective observational study

Objective: To compare the expression of progesterone receptors (A?+?B) and type-B progesterone receptors in the epithelial and stromal cells of fertile and infertile women.

Methods: Women were divided into two groups, the group of fertile controls (group 1) and the group of infertile women (group 2) and were set on regular ultrasound imaging in order to detect ovulation. An endometrial biopsy was obtained on the seventh or eighth post-ovulatory day. Immunohistochemistry was performed to measure percentage of positive nuclei, intensity of staining and h-score for progesterone receptors (PgR) (A?+?B) as well as type-B progesterone receptors in epithelial and stromal cells. Secondary outcomes included endometrial tissue dating, the rate of tissues being out-of-phase and endometrial thickness.

Results: Endometrial issue was obtained from 15 fertile and 30 infertile women. Expression of PgR (A?+?B) and PgR type-B was significantly lower in the epithelial cells of infertile women. PgR (A?+?B) h-score was 220.0?±?18.5 for fertile versus 147.3?±?18.0 for infertile women (p?=?0.02). PgR type-B h-score in epithelial cells was 166.8?±?30.7 for fertile versus 90.8?±?20.6 for infertile (p?=?0.04). No significant difference was observed in stromal cells.

Conclusions: Expression levels of PgR (A?+?B) as well as type-B receptors are significantly lower in the epithelial cells of infertile women during implantation window.     

Semen profile, testicular volume, and hormonal levels in infertile patients with varicoceles compared with fertile men with and without varicoceles

OBJECTIVE: To assess semen analysis, testicular volume, and hormone levels in fertile and infertile patients with varicoceles and fertile men without varicoceles. DESIGN: Retrospective study. SETTING: Academic medical center. PATIENT(S): Patients were divided into three groups: fertile men with varicoceles (n = 79), infertile men with varicoceles (n = 71), and fertile men without varicoceles (n = 217). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Levels of LH, FSH, and total T and testicular volume in fertile and infertile men with varicoceles and fertile controls without varicoceles. RESULT(S): LH (IU/L) and T (ng/dl) levels were not statistically different across the three groups. FSH levels were significantly higher in infertile men with varicoceles (7.8 +/- 7.6 IU/L) than in the fertile men with varicoceles (3.5 +/- 2.1 IU/L) or in fertile men without varicoceles (3.5 +/- 1.9 IU/L). The right testicle was smaller in infertile patients with varicoceles (18.7 +/- 8.3 cm(3)) than in fertile men with varicoceles (25.2 +/- 13 cm(3)) or in fertile men without varicoceles (24.9 +/- 10.7 cm(3)). In addition, the left testicle was smaller in infertile men with varioceles (17.6 +/- 8.9 cm(3)) than in fertile men with varicoceles (21.6 +/- 7.8 cm(3)) or in fertile men without varicoceles (23.4 +/- 8.3 cm(3)). Sperm concentration was lower in infertile men with varicoceles (33.7 +/- 23.3 x 10(6)/mL) than in fertile men with varicoceles (101.8 +/- 76.6 x 10(6)/mL) or in fertile men without varicoceles (111.8 +/- 74.2 x 10(6)/mL). In addition, sperm motility was lower in infertile men with varicoceles (37.2% +/- 23.9%) than in fertile men with varicoceles (53.9% +/- 17.4%) or fertile men without varicoceles (58.9% +/- 15.8%). CONCLUSION(S): Infertile patients with varicoceles have higher levels of FSH, smaller testes, and lower sperm concentration and motility compared with controls with or without varicoceles. No statistical differences were seen in the variables evaluated among the fertile men with incidental varicoceles detected at physical examination and those without varicoceles.     

Low endometrial beta-catenin and cadherins expression patterns are predictive for primary infertility and recurrent pregnancy loss

Inadequate uterine receptivity is responsible for two-third of implanting failures. Aim of the study was to investigate the role of epithelial adherence and tight-junction molecules expressed by human endometrium in predicting womens’ fertility outcome. A total of 76 consecutive women, including 24 fertile (G1), 40 primary infertile (G2), and 12 recurrent pregnancy loss (RPL, G3) women, who underwent diagnostic hysteroscopy plus endometrial biopsy between 2005 and 2016 at the Gynecology Division of Sant’Andrea Hospital, Sapienza University of Rome, in Italy, were retrospectively identified and included into the study. Endometrial biopsies were assessed for the immunohistochemical expression of beta-catenin (β-catenin), E-cadherin and K-cadherin biomarkers. Expression profiles were compared between the three groups of patients and were correlated with patients’ fertility outcome. In infertile patients there was a significant lower endometrial expression of β-catenin (p?=?.001), E-cadherin (p?=?.001) and K-cadherin (p?=?.002), compared to the fertile ones. Furthermore, β-catenin and E-cadherin intensity gradients of expression at glandular level were found totally reversed in infertile patients. Significant lower expression levels of K-catenin (p?=?.016) and E-cadherin (p?<?.0001) at glandular level were found in RPL patients. Results showed that the low endometrial expression of β-catenin, E-cadherin and K-cadherin were associated to fertility-related problems, such as primary intertility and RPL.     

Status of autoantibodies to zona pellucida in human reproduction

The sera of 80 patients were tested by the indirect immunofluorescence technique to evaluate the presence of autoantibodies to zona pellucida in human reproduction. The incidence of positive anti-zona activity was 71.4% (25/35) in the infertile women, 40.0% (6/15) in the normal, nonpregnant fertile women, 20.0% (3/15) in the normal pregnant women and 26.7% (4/15) in the normal fertile men, when unabsorbed sera were tested. To overcome false positive reactions due to nonspecific serum components, all the positive sera were absorbed with formalinized porcine red blood cells and retested. However, after absorption, anti-zona activity was lost in all the positive sera from non-pregnant fertile women, pregnant women and fertile men; but it was retained in 51.4% (18/35) of the infertile women. These positive sera (18) were further absorbed with zona-coated eggs and retested. Fluorescence was lost in all the positive sera, thus demonstrating the presence of antibodies specific to zona antigen in the infertile women. The study also revealed that autoantibodies to zona were seen more often in patients of greater age (26 to 40 years) and in those who had been infertile for a greater period of time (greater than 6 years).     

整合素配体玻连蛋白在人精子的表达及其与受精的关系

目的 :进一步研究整合素配体玻连蛋白 (Vn)在人精子的表达及其与受精的关系。方法 :选用 1 4例生育力正常的成年男性及 8例精液常规分析正常的不明原因不育男性患者的精液标本 ,液化后提取上游精子。精子体外获能后用兔抗人 Vn多克隆抗体及羊抗兔 Ig G-FITC行免疫染色。然后用流式细胞仪计数 Vn表达阳性精子百分数。部分获能精子同时与去透明带金黄地鼠卵行异种体外受精 (SPA)以检测其受精力 ,比较两组获能精子表面Vn表达阳性精子百分率及受精率差异并分析受精率与 Vn表达阳性的获能精子百分数之间的相关性。结果 :生育组与不育组获能精子 Vn表达水平分别为 2 1 .2 4± 1 1 .70 %与3.6 4± 3.2 7% ,不育组明显低于生育组 (P<0 .0 5)。生育组受精率大于 1 0 % ,不育组受精率小于 1 0 % ,符合划分生育力正常与异常的标准。所有标本 Vn表达阳性的获能精子百分率与精子受精率间具有相关性 (r=0 .476 )。结论 :人获能精子表面存在一定水平的整合素配体玻连蛋白表达 ;Vn参与受精过程 ;Vn表达异常可能与一些不明原因的不育有关     

人精子中芳香化酶表达与精子功能的关系

目的:研究精子细胞色素P450芳香化酶(P450arom)的表达及其与精子功能状态和受精力的关系。方法:以人精子穿透去透明带金黄地鼠卵异种体外受精试验(SPA)检测精子受精力;以三色法染色观察精子顶体反应(AR)的发生率。采用RT-PCR,用P450arom/GAPDH光密度值的比值代表P450arom的表达水平。结果:精子P450arom表达水平与受精率有一定的相关性(生育组r=0.5622;不育组r=0.6071)。正常男性与不明原因不育症患者精子P450arom/GAPDH比值分别为0.60±0.29,0.39±0.16,有显著差异(P<0.02)。P450arom表达水平与精子AR的发生率也有一定相关性(生育组r=0.5817;不育组r=0.5535)。结论:人精子中存在着P450arom表达产物;P450arom可能与精子功能有一定关系;P450arom表达异常可能与一些不明原因不育有关。     

Long-term survival of human spermatogonial stem cells in mouse testes

OBJECTIVE: To evaluate colonizing ability of human spermatogonial stem cells in mouse testes. DESIGN: Transplantation of human testis cells into the seminiferous tubules of immunodeficient mice. SETTING: University hospital and academic laboratory. PATIENT(S): Men with obstructive azoospermia or maturation arrest of spermatogenesis.Analyzed up to 6 months after transplantation. Also analyzed: cryopreservation of donor cells, donor cell concentrations, and leuprolide treatment of recipients. MAIN OUTCOME MEASURE(S): Detection of human donor cells in recipient testes using whole-mount immunohistochemistry with antibodies that react with human germ cells. RESULT(S): Mouse testes were colonized by human testis cells obtained from each of 6 patients; overall, human spermatogonia were found in 16 of 22 (73%) recipient testes. Human spermatogonial stem cells survived in mouse testes for at least 6 months and proliferated during the first month after transplantation. No human-differentiating spermatogonia were identified, and meiotic differentiation did not occur in mouse testes. In this initial study, human stem cell colonization was not influenced by cryopreservation of donor cells, donor cell concentration, or leuprolide treatment of recipient mice. CONCLUSION(S): Xenogeneic transplantation of human germ cells using mice as recipients is feasible and could be used as a biological assay system to further characterize human spermatogonial stem cells. This study might provide a mechanism to evaluate the status of the stem cell population in selected infertile male patients.     

Lactate and pyruvate utilization by the spermatozoa of infertile human males.

In studying the metabolic pathway of lactate and pyruvate in human spermatozoa from fertile and infertile subjects, pyruvate 1-C14 and lactate 1-C14 were used as substrates in a radiorespirometry system. Spermatozoa from patients with 20 +/- 2.0/10(6) spz/ml and decreased motility (group B) showed a more active decarboxylation of both pyruvate 1-C14 and lactate 1-C14 with a higher production of lactate C14, oxaloacetate, citrate, and isocitrate than those from fertile normal subjects (group A). Spermatozoa from fertile patients with normal counts but low motility (35 +/- 2.0% +++ motility) showed a similar rate of decarboxtlation of pyruvate 1-C14 but a greater rate of decarboxylation of lactate 1-C14 than those from fertile subjects. The low utilization of pyruvate by the spermatozoa from group C infertile patients, with intermediate counts and motility could be explained by a metabolic failure similar to that produced by some inhibitors of the respiratory chain. We do not have an explanation for the metabolic behavior observed in spermatozoa from group B patients, and further research on this point is desirable.     

Endocervical chlamydial deoxyribonucleic acid in infertile women

The presence of chlamydial deoxyribonucleic acid (DNA) was evaluated by DNA hybridization in endocervical cells of infertile and normal fertile women. Chlamydial DNA was detected in 49 of 186 (26.3%) infertile patients, which is significantly more common than in fertile control individuals (12.5%, or 8 of 64 individuals). Among infertile patients, 49.3% (33 of 67) of those with tubal factors as cause of infertility and 13.4% (16 of 119) of those with nontubal factors were found to contain chlamydial DNA in their endocervical cells. The results show that chlamydial DNA could be found significantly more frequently in endocervical cells of infertile patients with tubal factor than those without tubal factors or in normal controls.     

Dating sonographic endometrial images in the normal ovulatory cycle

Pelvic sonograms were obtained from 5 fertile volunteers and 150 infertile patients with normal ovulatory cycles, using real-time ultrasound. The existence of a linear cavity echo (C), thick hypoechoic layer (H) and increased echogenicity (E) were chosen as the parameters of sonographic endometrial images to be studied for dating the ovulatory cycle. In 109 serial sonograms from the fertile volunteers, H was observed from 3 days before ovulation (day -3) to ovulation day (day 0). E was observed from day +1 to day +8, and C, from day -10 to day +3. Studies on 189 sonograms from the infertile patients revealed a similar pattern for these parameters. We tested the accuracy of sonographic images of the endometrium, using sonograms from five patients who underwent hysterectomy. The measurements of endometrial thickness, in vivo, and in vitro, showed little difference. Sonographic endometrial images are considered indicative of histological changes, under the influence of estradiol and progesterone. Therefore, observation of the combined quantitative changes in C, H and E facilitates dating of the sonographic endometrial images in a normal ovulatory cycle.     

Comparison of age-related changes in anti-Müllerian hormone levels and other ovarian reserve tests between healthy fertile and infertile population

In this study, we aimed to determine whether anti-Müllerian hormone (AMH) levels vary between fertile and infertile populations and compare them with basal follicle-stimulating hormone (FSH) levels and antral follicle count (AFC). This was a prospective study that included 177 primarily infertile patients who underwent IVF treatment and 162 healthy fertile patients admitted to our clinic for benign diseases. FSH and AMH levels and the AFC of the infertile and fertile populations were compared between the age categories <30, 30–39 and?≥40. Correlations between AMH, basal FSH, and AFC with age were evaluated. AFC and AMH levels did not differ between the fertile and infertile groups in all age categories. AMH was inversely correlated with age in both the fertile and infertile populations. However, AFC revealed a stronger correlation with age in both the fertile and infertile populations compared with basal FSH and AMH. Age was positively correlated with basal FSH and inversely correlated with AMH and AFC. In conclusion, there was no significant difference between the fertile and infertile populations in terms of AMH or AFC. The decrease in ovarian reserve in infertile patients is directly related to age, not infertility.     

Variation in hyaluronan-binding protein 2 (HABP2) promoter region is associated with unexplained female infertility

We set up to analyze polymorphisms in hyaluronan-binding protein 2 (HABP2) gene in healthy fertile women (n = 158) and in women with unexplained infertility (n = 116) and to investigate the potential role of HABP2 in receptive endometrium. Minor rs1157916 A and the major rs2240879 A alleles together with AA genotypes were significantly less frequent in infertile women than in controls. Immunohistochemistry analysis of endometrial HABP2 expression at the time of implantation identified significantly lower HABP2 protein level in infertile women in stroma and vessels than in fertile women. Migration assay analysis of cultured trophoblast and endothelial cells toward HABP2 protein referred to the function of HABP2 in endometrial endothelial cells. In conclusion, our results indicate that polymorphisms in the regulatory region of HABP2 gene could influence gene expression levels in the receptive endometrium and could thereby be one reason for infertility complications in women with unexplained infertility. Additionally, HABP2 protein involvement in endometrial angiogenesis is proposed.     

Expression of D-mannose binding sites on human spermatozoa: comparison of fertile donors and infertile patients

OBJECTIVE: The hypothesis that defective expression of D-mannose binding sites (presumptive elements of the sperm-zona pellucida binding mechanism) is related to male infertility was tested. DESIGN: Experiments were performed on sperm samples from two groups of men classified, respectively, as fertile and infertile, based on their reproductive history. SETTING: The study was carried out in an andrologic laboratory of a University Hospital. PATIENTS, PARTICIPANTS: Fertile men were healthy sperm donors; infertile men were patients with fertility problems. INTERVENTIONS: D-mannose binding sites were visualized by fluorescence microscopy using a mannosylated neoglycoprotein probe. MAIN OUTCOME MEASURES: The hypothesis as reported in the objective section was formulated before data collection and was not modified thereafter. RESULTS: Sperm from fertile men displayed a characteristic pattern of changes in the expression of D-mannose binding sites during in vitro capacitation. This pattern was altered in sperm from infertile men. CONCLUSIONS: If the relationship between defective expression of D-mannose binding sites and decreased sperm fertilizing ability is validated by parallel tests of sperm-zona binding, it may be used for development of chemical tests replacing the current ones using human zonae pellucidae.