Hypoxia alters early gestation human cytotrophoblast differentiation/invasion in vitro and models the placental defects that occur in preeclampsia

During normal human pregnancy a subpopulation of fetal cytotrophoblast stem cells differentiate and invade the uterus and its arterioles. In the pregnancy disease preeclampsia, cytotrophoblast differentiation is abnormal and invasion is shallow. Thus, the placenta is relatively hypoxic. We investigated whether lowering oxygen tension affects cytotrophoblast differentiation and invasion. Previously we showed that when early gestation cytotrophoblast stem cells are cultured under standard conditions (20% O2) they differentiate/invade, replicating many aspects of the in vivo process. Specifically, the cells proliferate at a low rate and rapidly invade extracellular matrix (ECM) substrates, a phenomenon that requires switching their repertoire of integrin cell-ECM receptors, which are stage-specific antigens that mark specific transitions in the differentiation process. In this study we found that lowering oxygen tension to 2% did not change many of the cells' basic processes. However, there was a marked increase in their incorporation of [3H]thymidine and 5-bromo-2'-deoxyuridine (BrdU). Moreover, they failed to invade ECM substrates, due at least in part to their inability to completely switch their integrin repertoire. These changes mimic many of the alterations in cytotrophoblast differentiation/invasion that occur in preeclampsia, suggesting that oxygen tension plays an important role in regulating these processes in vivo.

Maternal smoking inhibits early human cytotrophoblast differentiation

Differentiation of the specialized epithelial cells of the placenta, termed cytotrophoblasts, is a particularly important aspect of placental development during the first trimester of pregnancy. During this process cytotrophoblast stem cells either fuse to form the syncytium or aggregate to form cell columns that adhere to, then invade the uterus. We found that chorionic villi from early gestation placentas of mothers who smoke showed a marked reduction in cell columns, a defect that could not be corrected by placing them in culture. We used two different in vitro models to determine if nicotine plays a role in the etiology of this defect. Exposing early gestation chorionic villi from nonsmoking women to nicotine inhibited subsequent cell column formation in vitro. Nicotine also inhibited normal first trimester cytotrophoblast invasion, apparently by reducing the ability of treated cells to synthesize and activate the 92 kDa type IV collagenase, an important mediator of invasion in vitro. These results suggest that maternal cigarette smoking inhibits the trophoblast differentiation pathway that leads to column formation and uterine invasion. This effect, which is due at least in part to the effects of nicotine, may contribute to the growth retardation observed in fetuses of mothers who smoke during pregnancy.

Effects of pentoxifylline on human sperm parameters in vitro

PURPOSE

Pentoxifylline was tested in three raising concentrations (0.7 mM/l, 1.5 mM/l, 3.6 mM/l) on human sperm cells in vitro.

METHODS

On 143 samples, we examined drug effect on motile sperm concentration, grade of their motility, acrosome reaction and membrane status.

RESULTS

Obtained results show improvement in motile sperm concentration, as well as in the grade of progression in the majority of samples.

CONCLUSIONS

Spermatozoa membranes as well as occurrence of the acrosomal reaction were not affected by pentoxifylline.

Sperm morphology and motility in different age populations

A prospective study of 77 semen specimens was conducted by routine examination of patients reporting to our laboratory for sterility problems. Abnormal spermatozoa were found mostly in patients over 40 years of age. The most frequent head abnormality was angulation of head (found in 94% of patients) and the most frequent tail abnormality was bent jail (found in 90% of patients). Immature spermatozoa were noted mostly in patients over 40 years of age. Motile sperm concentration was higher in patients up to 26 years of age. However, there was a remarkable heterogeneity of routine andrological parameters within the examined groups.

In vitro differentiation and ultrastructure of human extravillous trophoblast (EVT) cells

Tissue explants of anchoring villi from the first trimester placentae cultured on extracellular matrix (Matrigel) give rise to EVT cells in vitro. This study was designed to address two issues important for further application of the described in vitro model: first, were the observed EVT cells derived by cell proliferation in vitro and second, what is the degree of homology between the in vivo and the in vitro differentiated EVT cells. The cultures (tissue and matrix) were prepared for light and electron microscopic (EM) examinations. Semi-thin sections from Spurr epoxy resin-embedded tissue were used to 'pop-off' the selected area for EM examination. Cell proliferation in vitro was assessed immunohistochemically using proliferative cell nuclear antigen (PCNA) antibodies. Since positive hPL immunostaining has been consistently demonstrated in the invasive subpopulation of EVT cells from placental bed in situ, hPL staining was used as a marker of EVT cell differentiation in vitro. It has been demonstrated that PCNA antibodies immunostained nuclei of cytotrophoblast cells from cell column at the base of the anchoring villi, indicating that these cells expressed proliferative activity in vitro. Cytotrophoblast proliferation resulted in the formation of the flattened zone of cell outgrowths at the tip of anchoring villi. Cells from the distal layer of the cell column detached gradually and migrated into the surrounding matrix. These cells appeared as individual, round-shaped EVT cells with smooth surface cell membrane. Their cytoplasm was rich in glycogen and contained large lipid droplets and flattened cisternae of the RER. Positive PCNA immunostaining, along with the presence of mitotic figures, indicated that EVT cells in vitro retained the ability for cell proliferation. As a result of cell proliferation and migration, the number of EVT cells increased during the culture period of 4 days. EVT cell glycogen content and lipid stores decreased progressively as they migrated into the matrix. Individual EVT cells, as well as EVT cell clusters, became surrounded by the clear zone of digested matrix. Some cells started to express strong positive staining with hPL antibodies as soon as they had migrated outside the villous explant. By day 4 of culture, a small percentage of EVT cells (about 5-10%) ceased to migrate, firmly attached to the substratum and appeared as irregular shaped cells with filopodia-like projections. Their cytoplasm contained dilated cisternae of RER, a small number of glycogen granules and bundles of actin-like filaments located in the cytoplasm inside the plasma membrane.(ABSTRACT TRUNCATED AT 400 WORDS)

Intrauterine insemination as a successful method in the treatment of infertility caused by oligospermia

Intrauterine insemination combined with controlled ovarian hyperstimulation was used in treating couples with infertility problem caused by oligospermia. We reported 85 cases, with sperm number less than 20.0 x 10(6) per insemination sample. We obtained successful insemination with 0.7 x 10(6) motile sperm cells per insemination sample. We were particularly successful in treating severe oligospermia. Most of the pregnancies in our population of patients ended in delivering singletons. In conclusion, infertility caused by oligospermia may be successfully treated using IUI with controlled ovarian stimulation. Our opinion is that the accuracy of IUI timing is critical, especially when severe oligospermia is concerned.

Gonadotropins (FSH and LH) and testosterone in human male serum and seminal plasma

Concentrations of gonadotropins (FSH and LH) and testosterone (T) were measured in male serum and the seminal plasma of normo-, oligo- and azoospermic ejaculates. In addition, T levels were measured in tissue extracts of testis and prostate. The concentrations of FSH were nearly the same in seminal plasma and serum. However LH levels were higher in seminal plasma, while T levels were higher in serum. In azoospermic samples, the gonadotropins showed increased concentrations, while T levels were decreased. The concentrations of all three hormones differed in the seminal plasma of infertile men compared to the control group.

Lectin binding as a biological test in vitro for the prediction of functional activity of human spermatozoa

Adequate acrosome reaction is one of the essential events that has to occur in successful mammalian fertilization. The purpose of the present study was to assess the acrosome reaction in human spermatozoa by means of iodine-labelled lectins concanavalin A and peanut agglutinin ([125I]Con A and [125I]PNA). Six sperm samples in the control (fertile) group were compared with 24 samples obtained from infertile patients. The acrosome reaction in both groups was induced in vitro by adding follicular fluid. Iodine-labelled lectins were bound to the sperm surface, and alteration in the binding capacity for [125I]PNA and [125I]Con A after induced acrosomal reaction was the main parameter for the prediction of acrosome reaction and fertilizing ability. It is hoped that with the availability of this test, in-vivo data may be accumulated.

Human trophoblast cultures: models for implantation and peri-implantation toxicology

Implantation is the process that leads from blastocyst attachment to its embedding in the uterine wall. It is widely believed that failure of implantation is a common cause of pregnancy loss. Toxic agents can interfere directly with the process of implantation and therefore may account for unexplained implantation failures. Our knowledge of human implantation remains limited, mainly due to the lack of adequate experimental models. Studies of mechanisms underlying implantation in humans are by nature and for ethical reasons restricted to in vitro models. The aim of this review is to provide a critical evaluation of various in vitro models of implantation in humans, as well as essential background knowledge required for application of these models to the assessment of peri-implantation toxicity. Particular attention has been devoted to cell-cell and cell-matrix interactions as possible endpoints in the screening of toxic agents.

Healing effect of human trophoblast on indolent wounds

This study reports on the results of a trial in which the cytosol extract of trophoblast obtained from legal abortions was used for the treatment of indolent leg ulcers and severe chronic cystitis caused by irradiation therapy.

Villous culture of first trimester human placenta--model to study extravillous trophoblast (EVT) differentiation

During implantation and subsequent placentation the human extravillous trophoblast (EVT) cells invade the endometrium and maternal vasculature within the uterus. The origin of the EVT and signals triggering its differentiation, migration and invasion are poorly understood. First and second trimester human chorionic villi explants were used as a source of EVT and a variety of substrates which resemble extracellular matrix (ECM) in vivo have been tested to induce EVT differentiation and migration. The obtained results demonstrate that villous explants from both 5-7 and 8-10 weeks of gestation give rise to EVT cells in vitro if maintained on the surface of Matrigel or decidual extract supplemented collagen gel. Fetal calf serum (FCS) supplemented media was essential for EVT differentiation and villous trophoblast viability. Immunostaining of both EVT cells and cells from the cytotrophoblastic column with monoclonal antibody Ki67 (cell proliferation marker) indicate that EVT cells differentiate in vitro by proliferation from the tip of anchoring villi. These mononucleated, round-shaped, migrating cells are HLA-A,B,C class I antigen (W6/32) antibody and low molecular weight cytokeratin positive, and do not immunostain with PAI-1 (plasminogen activator inhibitor) and HPL antibodies. Differentiation of EVT was restricted to first trimester villous tissue; explants from second trimester placentae did not give rise to EVT. Tissue viability as monitored by glucose utilization, lactate, progesterone and hCG production rates correlated with EVT differentiation. The production rates for hCG demonstrated significant variation among individual placentae and was maintained constant for 10 days consistently only in explants cultured on decidual extract supplemented collagen matrix. The described villous tissue culture system may be, therefore, a unique in vitro model to study proliferation and differentiation of EVT from cytotrophoblastic columns, the regulation of EVT proliferation and differentiation, the role of ECM in the induction of the migration and the interaction of extravillous and villous trophoblast at the level of the cytotrophoblastic column.

Immunohistochemical localisation of transforming growth factor-beta in first and third trimester human placenta

Recently it has been demonstrated that human placental tissue is a source of transforming growth factor-beta (TGF-beta) and that it expresses high TGF-beta mRNA activity. For a better understanding of its in vivo function, it was necessary to determine the site of TGF-beta synthesis in placenta. We have demonstrated that TGF-beta immunoreactivity is present in the cytoplasm of syncytiotrophoblast cells in both early and term placenta. The most intense staining was, however, observed in the first trimester trophoblast syncytial sprouts known to be an early stage in the development of placental villi. These results suggest the involvement of TGF-beta in the paracrine regulation of trophoblast-endometrial interaction.

Intrauterine insemination with spermatozoa recovered from the aspirate of artificial spermatocoele

Congenital absence of both vas deferens accounts for approximately 10% of cases of obstructive azoospermia. The purpose of the present study was to develop a treatment protocol for a group of azoospermic patients using surgical implantation of alloplastic spermatocoele to enable repeated sperm cell aspiration. Nine patients with congenital absence of both vas deferens, two with obstructed and one with destroyed vas, underwent surgery for the implantation of an alloplastic spermatocoele. In 10 of the 12 patients, vital spermatozoa were recovered from the aspirate and used for intrauterine insemination of their female partners with induced ovulation, some of whom then conceived.

Coincubation--an experimental approach to the study of decidual-trophoblast interaction

Coincubation of trophoblast and decidual tissue explants was used for the study of placental-endometrial interaction in early pregnancy. To this end two types of experiments were performed: coincubation with (type A) and without (type B) direct tissue contact. The rate of incorporation of [14C]leucine into cytosol proteins in both tissues was employed for the estimation of total protein synthesis. Prolactin production in vitro was used as a specific marker of the decidual and hCG of the trophoblast cell function. The results show that the type A coincubation experiments produced a strong inhibition of cytosol protein synthesis in both tissues. PRL production by the decidual tissue and hCG production by the trophoblast tissue was reduced. In the type B coincubation experiments protein synthesis and prolactin production by the decidual tissue remained within the control range. In the trophoblast tissue explants protein synthesis and hCG production were depressed. The degree of inhibition was, however, lower than that in type-A experiments. Based on these results it was concluded that the in vitro model of coincubation of trophoblast and decidual tissue explants is suitable for the study of the role of tissue interactions in vitro.

Post-irradiation cystitis improved by instillation of early placental extract in saline

21 patients with chronic cystitis due to irradiation therapy for carcinoma of the cervix had symptomatic and cystoscopic improvement from instillations of early placental extract in saline. There was a statistically significant difference between these patients and a control group.

Effect of morphine on hCG release by first trimester human trophoblast in vitro

Opiate synthesis by human placental cells and the presence of kappa-type opiate binding sites in the syncytiotrophoblast brush border membrane may indicate the possible role of morphine-like substances in the autocrine regulation of trophoblast cell metabolism. This study was undertaken to examine the in vitro effect of morphine on hCG (human chorionic gonadotrophin) and hPL (human placental lactogen) release by 1st and 3rd trimester placental tissue explants. The results have shown that morphine (100 nM) significantly stimulated hCG secretion by 6-8 weeks old trophoblast and was without effect on hPL. Hormone secretion by term placental tissue explants was unaffected by morphine treatment. Based on these results we assume that opiates may have a role in the local (autocrine and/or paracrine) regulation of hCG secretion in early gestation.

Effect of cAMP on cytosol protein phosphorylation in placental tissue of different gestational age

Phosphorylation of cytosol proteins in placental tissue of different gestational age has been studied. Cytosol protein phosphorylation was stimulated by exogenous cAMP only in term placentae and remained unchanged in first and second trimester placentae. Exogenous proteins, histone and casein, were intensively phosphorylated by cytosol kinases with maximal activities in first trimester cytosol preparations. Exogenous cAMP stimulated histone phosphorylation, but it had no effect on casein phosphorylation. On the basis of the obtained results it can be concluded that endogenous protein phosphorylation in first and second trimester placental cytosol is cAMP independent.

[Determination of the concentration of sex hormone-binding globulin in the clinical evaluation of women with secondary amenorrhea]

The serum SHGB (sex-hormone-binding globulin) concentration was measured in patients with secondary amenorrhea in order to determine its role in the regulation of androgen and estrogen metabolism in the course of the normal and irregular menstrual cycle. SHBG concentration was lower than in the control group in 52% of amenorrheic patients, but this difference was not statistically significant due to great individual variations. If the patients were divided in 2 groups according to Prolactin (PRL) concentration, significant decrease in SHGB concentration was observed in the group with elevated PRL concentrations. Correlation of SHBG with estrogen (E2), testosterone (T), progesterone (PRG) and PRL was tested and results show the weak correlation (r = 0.4) between SHGB and T and more significant correlation between SHGB and E2 in the group with basal E2 concentration below 100 pmol/1. SHGB test should be included in the evaluation of alterations of androgen and estrogen metabolism.

In vitro effect of ritodrinum on cAMP concentration in human placentas of different gestational age

Beta-sympathomimetic drugs are clinically widely used in the management of threatened premature labour. The existence of beta-adrenergic receptors has been demonstrated in the human placenta and, as the stimulation of beta-adrenoreceptors is known to be mediated by cAMP, the purpose of this study was to compare the effect of Ritodrinum on cAMP concentration in placentas of different gestational age. The in vitro treatment with Ritodrinum induced a five fold increase in cAMP concentration in 6-8 week old placenta, three fold increase in midgestation, but was without effect in term placenta. This result suggest that beta-mimetics in pharmacological concentrations could modulate trophoblast cell activity through the cAMP-dependent system during the first half of gestation.

Hormone profile in hyperprolactinemic infertile men

Serum levels of FSH, LH, prolactin, testosterone, and estradiol in 46 infertile men with hyperprolactinemia were compared with the same in 50 infertile and 30 fertile men with normal serum prolactin levels. Serum FSH levels in hyperprolactinemic men were significantly higher than in the other groups, indicating disturbance of spermatogenic process among those men. Significantly raised serum LH levels were in infertile men with serum prolactin over 1000 U/liter. All men with hyperprolactinemia had significantly lower serum testosterone levels than other infertile and fertile men. Although serum testosterone was not under the lower limit of normal range and high LH levels demonstrated disturbance of Leydig cell function in hyperprolactinemic infertile men, serum estradiol levels were not different among investigated groups. Azoospermic men with raised serum prolactin had higher serum FSH and LH levels than oligospermic men with hyperprolactinemia. These data demonstrated disturbance in hypothalamopituitary-testicular axis in infertile men with hyperprolactinemia. Further studies of prolactin in males with reproductive failure could probably clear this problem.