Phytoestrogen effects on vaginal microbiocenosis of Sprague-Dawley rats

Phytoestrogens present in the plants endemic for Chile were studied. The effects of phytoextract [specimen of preparation No. 181 (fraction b)] on target tissues were similar to those of estradiol. The preparation inhibited the stimulatory effect of estradiol on vaginal lactobacilli population.

Imprinting: perinatal exposures cause the development of diseases during the adult age

Since the early reports linking the development of clear cell cervicovaginal adenocarcinoma in young women with diethylstilbestrol treatment of their mothers during pregnancy, it became clear that perinatal exposure to several substances may induce irreversible alterations, that can be detected later in life. Current evidence suggests that these substances induce, by the mechanism of imprinting, alterations of the differentiation of several cell-types, resulting in the development of disease during the adult age. The most known delayed effects to prenatal exposure to agents displaying hormone action, pollutants, food additives and natural food components, substances of abuse and stress by the mechanism of imprinting are described. Among them, estrogens, androgens, progestins, lead, benzopyrenes, ozone, dioxins, DDT, DDE, methoxychlor, chlordecone, parathion, malathion, polychlorobiphenyls, pyrethroids, paraquat, food additives, normal food constituents, tetrahydrocannabinol, cocaine and opiates. It is concluded that perinatal exposure to several agents causes irreversible changes that determine health conditions during adulthood. Several diseases developing during adulthood probably were determined during early stages of life, under the effect of exposure or preferential mother's diet during pregnancy. Regulations to avoid these early exposures may contribute to an important improvement of health conditions of humankind.

[Patients with rheumatoid arthritis: study of the correlation between density of glucocorticoid receptors in synovial cells and clinical response to steroidal treatment]

BACKGROUND

The target cellular response to glucocorticoids is proportional to the concentrations or affinity of specific receptors to these substances.

AIM

To look for a correlation between glucocorticoid receptor concentrations in synovial wall cells and the clinical response to steroidal treatment in patients with rheumatoid arthritis.

PATIENTS AND METHODS

Twenty eight patients with rheumatoid arthritis were studied. Each subject was subjected to a synovial biopsy, in which a dry radioautographic technique for diffusible compounds was used. Patients were treated afterwards with three 500 mg intravenous pulses of methilprednisolone.

RESULTS

A mean of 44.8% of synovial cells (range 30.1-62.8%) had binding sites for 3H dexamethasone. All patients had a significant clinical improvement after methylprednisolone. Multiple regression analysis did not show a correlation between clinical response and glucocorticoid receptor concentration.

CONCLUSIONS

The lack of association between glucocorticoid receptor concentrations and clinical response could be due to the large steroid dose used, that saturated all available receptors.

[Role of sex hormones in autoimmune diseases]

There is increasing body of evidence to suggest that sex hormones may be closely involved in the pathogenesis of autoimmune diseases in humans. In the present article we discuss heteroimmune response differences between males and females and the roles of gender and sex hormones in autoimmune diseases in various species. The general conclusions are the following. Androgens and perhaps progestogens may protect from autoimmune disease; however oestrogens seems to have a dualistic effect on the immune system. Is has been demonstrated that oestrogens suppress antigen-specific T-cell dependent immune reactions while enhance B-cell activities.

Early postnatal androgenization imprints selective changes in the action of estrogens in the rat uterus

Exposure of animals perinatally to some hormonally active agents may imprint permanent changes on the action of related hormones. The present study investigated the effects of early postnatal androgenization on various genomic responses to estrogen in the uterus of prepubertal rats. Female rats were androgenized at postnatal ages of 1, 5, or 13 days with a single s.c. injection of testosterone propionate. At the age of 21 days, the animals were stimulated with estrogens. The uteri of androgenized and control rats were analyzed morphometrically to measure genomic parameters of estrogen stimulation in the uterus. The results demonstrate that early postnatal androgenization does not equally affect all uterine cell types and that the effects of androgenization change according to the age at androgenization. The dissociation between the various responses according to the time of androgenization suggests that there are critical ages at which the uterine cell types that respond to estrogens can be altered permanently by imprinting. The finding of changes in the action of estrogen induced by androgenization at older than neonatal ages in the rat suggests that similar changes may occur in humans exposed to androgens during their extrauterine life. This result also points to the need for further studies using the rhesus monkey because of its close resemblance to the human with respect to female reproductive physiology.

Intraarticular progesterone inhibits 3H-dexamethasone binding to synovial cells from patients with rheumatoid arthritis. A study by dry radioautographic technique

Glucocorticoids are known to exert their antiinflammatory effects through an interaction with specific hormone receptors. Progesterone is able to bind to these glucocorticoid receptors exerting either agonistic or antagonistic actions. We have reported that a single intraarticular injection of progesterone exerts a local antiinflammatory action in patients with rheumatoid arthritis (RA), suggesting an agonistic effect of progesterone on local glucocorticoid receptors. To corroborate this possible mechanism of action, we investigated the binding of 3H-dexamethasone to local glucocorticoid receptors in synovial tissue from 3 patients with active RA, before and 14 days after a single intraarticular injection of progesterone. Both cytoplasmic and nuclear 3H-dexamethasone binding sites were observed within synoviocytes, macrophages, fibroblasts, lymphocytes and endothelial cells. Dry radioautograms of biopsied synovial tissue demonstrated a marked decrease of 3H-dexamethasone binding following progesterone treatment in all patients (p less than 0.001 for each comparison). Although the number of cases is not large enough to draw definitive conclusions, our data confirm the marked anti-inflammatory effect of intraarticular progesterone and support the hypothesis of an agonistic effect of progesterone (or its metabolites) on glucocorticoid receptors.

Effect of eosinophil-degranulating estrogens on spleen eosinophils and white pulp/red pulp ratio

A role for eosinophils in the immune reaction has not been yet established. Considering that these leukocytes accumulate in lymphoid organs under glucocorticoid stimulation, we explored the possibility that they participate in the depression of immune reactions induced by these hormones and that they degranulate to exert this action. In this context, we investigated the dose effect of three estrogens on the number and degranulation of spleen red pulp eosinophils and on the percentage of spleen cross sectional area comprising white pulp. Estradiol-17 beta or 4 (OH) estradiol-17 beta increased red pulp eosinophils at low doses: 2 (OH) estradiol-17 beta increased them at a very high dose. The three estrogens degranulated the spleen eosinophils and decreased the lymphocyte containing spleen white pulp. We propose that the decrease in white pulp is a response mediated by agents released from degranulating eosinophils under the action of estrogen. Consequently, both estrogen-induced eosinophil degranulation and estrogen-induced increase in red pulp eosinophil numbers are conditions contributing to a decrease in white pulp volume. All above evidence supports the hypothesis that eosinophils are involved in immunoregulation by diminishing the number of lymphocytes contained in lymphoid organs.

Effect of ketotifen on the distribution and degranulation of uterine eosinophils in estrogen-treated rats

Eosinophil leukocytes migrate from the blood to the uterus under estrogen stimulation, redistribute through uterine extravascular compartment, degranulate in the organ, and release agents that are involved in several parameters of estrogen action. Agents that induce blood eosinopenia, block their migration to the uterus, interfere with their redistribution within the organ or modify their degranulation, selectively interfere with eosinophil-mediated responses to estrogen. The present study investigated whether ketotifen, an antiallergic agent that inhibits allergen-induced eosinophil degranulation, interferes with estrogen-induced eosinophil migration to the uterus and their subsequent degranulation. Ketotifen does not interfere with estrogen-induced eosinophil accumulation in the uterus, but decreases the proportion of eosinophils located in endometrium and inhibits their degranulation. These results suggest that neither histamine, calcium or slow reacting substance of anaphilaxis are involved in eosinophil migration to the uterus. The inhibition by ketotifen of eosinophil degranulation may diminish eosinophil migration through extravascular compartment via a decrease in the release from degranulating eosinophils of enzymes required for this migration. It is possible that the inhibition by ketotifen of both, eosinophil degranulation and eosinophil motility through uterine extravascular compartment, interfere with eosinophil-mediated responses to estrogen or with other functions of these cells.

Prenatal androgenization selectively modifies some responses to oestrogen in the prepubertal rat uterus

Exposure of fetuses to some hormonally active agents may imprint permanent changes on the action of related hormones. These changes can be detected in adulthood as a modification of the degree of responsiveness to hormone action. The present study describes the effect of prenatal androgenization on the various responses to oestrogen in different types of cells in the uterus of prepubertal rats. Prenatal androgenization completely abolishes oestrogen-induced hypertrophy of uterine luminal and glandular epithelium, while it does not interfere with hypertrophy of circular myometrium and potentiates uterine eosinophilia and oedema. This dissociation between the various responses to oestrogen suggests that prenatal androgenization does not equally affect all uterine cell types.

The estrogenic responses to clomiphene in the different cell types of the rat uterus: morphometrical evaluation

The present study was designed to investigate the dose-response of clomiphene on several estrogenic responses in the immature rat uterus and to compare it to available data on estradiol-17 beta. A dissociation was demonstrated among the different estrogenic responses induced by clomiphene. Very high doses of clomiphene were needed to induce the 6-h uterine eosinophilia and deep endometrial edema, and maximal response levels were not reached at any dose studied. On the contrary, many genomic responses were induced with much lower doses of clomiphene, and maximal response levels were reached with at least the two highest doses of clomiphene. This dissociation is in agreement with the existence of separate groups of responses that are mediated by multiple and independent mechanisms of estrogen action involving different kind of receptors. Luminal epithelial, glandular epithelial, and myometrial hypertrophies were also found to differ with regard to the dose needed to induce this response in each cell type. The dissociation between genomic responses of the different uterine cell types supports the hypothesis of different estrogen receptors for each kind of cell. Clomiphene induces mitoses in the different cell types, but the proportion of mitoses in the cell types was different from that described for estradiol. It is suggested that these differences are also due to differences between receptors involved in cell proliferation.

Differential potency of oestradiol-17 beta and diethylstilboestrol on separate groups of responses in the rat uterus

The present study describes the effects of oestradiol-17 beta and diethylstilboestrol (DES) on several oestrogenic responses in the immature rat uterus Diethylstilboestrol was weaker than oestradiol in inducing uterine eosinophilia, water imbibition and mitoses, as strong as oestradiol in eliciting epithelial hypertrophy at 24 h after treatment, and stronger than oestradiol in eliciting the reduction of epithelial cell height at 6 h after treatment and myometrial cell hypertrophy at 24 h after treatment. In addition, differences among the mitotic responses to oestrogen of the different uterine cell types were also detected. The above dissociation of the effects of DES and oestradiol-17 beta is in agreement with the hypothesis that eosinophil-mediated non-genomic responses, genomic responses and cell proliferation are mediated by independent mechanisms, involving different receptors which may have different affinities for both compounds. The eosinopenia and eosinophil degranulation under DES treatment suggest an explanation for the effect of DES on water imbibition. The dissociation among genomic responses from the different uterine cell types supports the hypothesis that different kinds of cytosol-nuclear oestrogen receptors exist.

Colloidal carbon blocks oestrogen-induced migration of eosinophils to the uterus and the uterine water imbibition response

Oestrogen induces a migration of eosinophil leukocytes to the uterus where, it is suggested, these cells mediate several responses to hormone stimulation. To investigate the mechanism of the recognition of the uterus by the eosinophils, the present study describes the effect of a blockade of the rat reticulo-endothelial system with colloidal carbon on oestrogen-induced uterine eosinophilia, and other responses to oestrogen stimulation that, it has been suggested, are mediated by eosinophils. In the absence of oestrogen colloidal carbon induced an increase in the number of eosinophils in mesometrium but not in endometrium with myometrium, and a slight oedematous reaction in deep endometrium. Colloidal carbon abolished the oestrogen-induced increase in the number of eosinophils in endometrium with myometrium and drastically decreased the oestrogen-induced increase in uterine wet weight and the endometrial oedematous responses 6 h after the administration of oestrogen. The present results agree with the hypothesis that most uterine water imbibition is mediated by eosinophils and suggest a possible mechanism for the interaction of colloidal carbon with eosinophil migration to the uterus.

Effect of various doses of catecholestrogens on uterine eosinophilia in the immature rat

This paper describes the induction of uterine eosinophilia as well as of deep endometrial edema and increase of uterine wet weight in the immature rat by the catecholestrogens 2-OH-estradiol and 4-OH-estradiol. These effects are thought to be mediated by eosinophils via a specific eosinophil receptor system. 4-OH-estradiol was equipotent with estradiol, whereas the effect of 2-OH-estradiol was significantly weaker.

Degranulatory action of estradiol on blood eosinophil leukocytes in vivo and in vitro

The degranulatory activity of estradiol was tested on blood eosinophil leukocytes in vivo and in vitro. Treatment of adult ovariectomized rats with 30 micrograms estradiol/100 g body wt. increased the percentage of degranulated eosinophils from 10% to about 70% at 6 or 24 h after treatment, and increased the rate of in vitro eosinophil degranulation of those eosinophils that were non-degranulated at the time of blood sample collection. The addition of estradiol to blood samples from untreated ovariectomized rats (0.05 micrograms/ml) increased the percentage of eosinophils degranulated in vitro at 1 h of incubation from 20% to near 60%. It is suggested that estrogen acts directly on the eosinophils, probably via specific hormone receptors. Considering the hypothesis that eosinophils are involved in the mediation of a group of responses to estrogen in the uterus, it is proposed that the hormone-induced degranulation of these cells may have physiological implications in the regulation of the intensity and duration of the eosinophil-mediated responses. In addition, estrogen-induced eosinophil degranulation may interfere with the action of eosinophils that have migrated to other target organs (lymphoid organs, etc.) under the action of other agents (glucocorticoid hormones, histamine, etc.) or conditions (immune reactions, etc.).

Dissociation of uterine eosinophilia and water imbibition from other estrogen-induced responses by nafoxidine pretreatment

We investigated the effect of pretreatment of immature rats with 5 or 50 micrograms nafoxidine (UA), or with 0.05 micrograms 17 beta-estradiol (E2) on several uterine responses elicited by treatment with a test injection of 15 micrograms E2, administered 48 h after pretreatment. Early (6 h) and late (24 h) responses were measured, including wet weight, RNA, protein and glycogen content and number of blood eosinophils per uterus. The results showed that, like a 24 h pretreatment with 5 micrograms UA, a 48 h pretreatment with either of the UA doses dissociated the early wet weight response from the late responses to E2 treatment, only the former being restored. In the case of E2 pretreatment, both types of response to E2 treatment were reinstalled. By contrast, uterine eosinophilia, induced 6 and 24 h after E2 treatment, was not only restored but even markedly amplified following any of the 3 pretreatments. This was obtained without amplification of the early wet weight response and with various levels of the other parameters at the time of administration of the test E2 injection (i.e. due to the pretreatment alone). From this it may be concluded that if the previously documented correlation between estrogen-induced eosinophilia and edema actually reflects the existence of a causal link between the 2 responses, as postulated by Tchernitchin in 1972, this would be with eosinophils controlling edema, rather than the reverse. Testable working hypotheses for the mechanism of amplification of the eosinophil response are proposed.

Inhibition of non-genomic responses to oestrogen in the rat uterus by testosterone propionate

Testosterone propionate (50 mg/kg), administered together with oestradiol, inhibited the oestrogen-induced uterine eosinophilia, deep endometrial oedema and the increase in uterine wet weight, 6 h after treatment. The same dose of the androgen decreased the number of eosinophils in the blood and increased their degranulation, explaining the effect of testosterone in the uterus. The high doses of the androgen used were in the range of the doses reported by others to block selectively the oestrogen-induced increase in uterine peroxidase content but not other responses to oestrogen or the cytosolic oestrogen receptor translocation to the nucleus. The dissociation by high doses of testosterone of the oestrogen-induced uterine eosinophilia, wet weight increase and oedema from other responses to oestrogen in the absence of any measurable effect of testosterone upon cytosolic-nuclear oestrogen receptors supports the idea that uterine eosinophilia and oedema are oestrogenic responses regulated by mechanisms different from those of the genomic responses, and is in agreement with the hypothesis of the mediation of uterine oedema by eosinophils.

Cellular distribution of dexamethasone in rabbit spleen and lymph nodes

The binding of tritiated dexamethasone by rabbit spleen and lymph nodes was studied in vivo by dry radioautography. The labeled glucocorticoid was found in the surface and cytoplasm of eosinophil leukocytes and in the nuclei of reticular cells, plasmocytes, endothelial cells and macrophages, but not in lymphocytes, lymphoblasts or plasmoblasts. Additional administration of excess of excess of non-radioactive dexamethasone suppressed this labeling. The findings are discussed in relation to the mechanism of action of glucocorticoids in lymphoid organs.

Progesterone interaction with eosinophils and with responses already induced by oestrogen in the uterus

Progesterone pretreatment decreases oestrogen-induced uterine eosinophilia and other non-genomic responses that are possibly mediated by eosinophils. To investigate the mechanisms of this interaction, the present study describes the effects of progesterone on oestrogenic responses already induced by oestrogen treatment and the in-vivo and in-vitro effects of progesterone on blood eosinophils. Progesterone treatment of oestrogen-pretreated animals potentiated uterine eosinophilia 24 h after progesterone treatment but decreased it at later times and increased eosinophil degranulation in vivo. In addition, progesterone degranulated blood eosinophils in vitro. These findings demonstrate interaction of progesterone with oestrogenic responses mediated by eosinophils. Progesterone interaction with other oestrogenic responses was analysed for comparison; evidence is shown suggesting a role of eosinophils in oestrogen-induced uterine luminal fluid accumulation.

Time-course of the effects of nafoxidine and oestradiol on separate groups of responses in the uterus of the immature rat

The effects of 0.05 or 15 micrograms oestradiol, and of 5 or 50 micrograms nafoxidine on the uterus of immature rats were investigated. Nafoxidine appeared at least as efficient as oestradiol for the action on RNA, protein and glycogen content but was less efficient for inducing early increase in wet weight and in eosinophil migration into the uterus. If eosinophil counts in the deep stroma were considered, a strong parallelism was revealed between this response and the increase in wet weight. These results represent a further argument for a dissociation between early and late effects of oestrogens and for the existence of separate sites of hormone action. They also lend support to the hypothesis of a mediation of wet weight response by eosinophils.

Methods for the evaluation of responses to estrogen in individual cell types or regions of the uterus

Nongenomic responses to estrogen and the genomic responses in the different uterine cell types can be dissociated selectively. The present report describes morphometric methods for the evaluation of estrogen-induced uterine edema and of genomic responses in individual cell types. The morphometric measurements of the genomic responses correlated with a classically accepted biochemical method of genomic response evaluation in the uterus (increase in RNA/DNA). Edema correlated with the classically accepted method of evaluation of uterine water imbibition, i.e., estrogen-induced increase in uterine wet weight 6 h after hormone administration.

Oestrogen levels in the blood, not in the uterus, determine uterine eosinophilia and oedema

This work was aimed at testing whether oestrogen-induced changes in the uterus are responsible for uterine eosinophil migration or whether the effect is due to a direct action of oestrogen on the eosinophils themselves. Uterine eosinophil migration in response to intraluminal administration of oestradiol-17 beta into one uterine horn was measured in the injected and in the untreated contralateral horns. Uterine genomic responses (luminal epithelial and myometrial hypertrophy and nucleolar enlargement), known to depend on the local intra-uterine oestrogen level, were measured to control for the absence of hormone recirculation to the uninjected horn. The effects of intravenously administered oestradiol were also determined. Intraluminal injection of 0 X 1 ng oestradiol had no effect on either horn. With 10 ng, only the injected horn exhibited the genomic responses while eosinophilia developed to the same extent in both horns. With 100 ng, the genomic responses and eosinophilia were identical in injected and in contralateral horns. The results show that eosinophil migration depends on systemic levels of oestrogen, thus indicating that it is due to an oestrogen-induced change in a property of eosinophil leukocytes rather than a change in the uterus itself. As water imbibition showed the same pattern of responses as eosinophilia, this lends further support to the hypothesis of a role for eosinophils in oestrogen-induced uterine oedema.

Eosinophil-mediated non-genomic parameters of estrogen stimulation--a separate group of responses mediated by an independent mechanism

The present report describes evidence suggesting that eosinophil leukocytes mediate a separate group of responses to estrogens (uterine edema, increase in vascular permeability, release of histamine etc.) independently from genomic activation. Conditions suppressing genomic activation do not interfere with this group of responses. Conditions interfering with eosinophil leukocyte migration to the uterus (young age blood eosinopenia, eosinopenic hormones, agents blocking cell mobility) selectively interfere with this group of responses. It was proposed that estrogen cytosol-nuclear receptors are involved in estrogen-induced genomic activation, and that estrogen receptors from eosinophil leukocytes are involved in the migration of these cells to the uterus, where they would mediate the above responses. Conditions increasing (theophylline) or decreasing (thyroid hormones, insulin) estrogen binding by eosinophils selectively modify estrogen-induced uterine eosinophilia and the responses to estrogen proposed to be mediated by eosinophils in the uterus. A mechanism is proposed explaining estrogen effects mediated by eosinophils.

Effect of progesterone on the non-genomic response to oestrogen in the rat

Different effects of oestrogen are mediated separately, by independent mechanisms of action. Accordingly, it has been shown that it is possible to dissociate these effects under various conditions which stimulate or inhibit responses selectively. The present study describes the action of progesterone on non-genomic responses to oestrogen stimulation which, it has been suggested, are mediated by eosinophils. Oestrogen induced an increase in the number of eosinophils in the rat uterus, an increase in uterine wet weight and oedema of deep endometrial stroma (measured as decrease in cellular density). Progesterone induced a slight oedematous reaction in superficial endometrial stroma but did not induce uterine eosinophilia. Progesterone pretreatment of oestrogen-treated rats did not block oestrogen-induced uterine eosinophilia and oedema but induced an increase in the degranulation of uterine eosinophils. Therefore the number of eosinophils decreased without any change in the uterine oedema induced after 6h of oestrogen action. The results corroborate previously published evidence of a dissociation of the action of oestrogen in independent groups of responses. Progesterone, a known blocker of some oestrogenic responses, did not block the effects mediated by eosinophils at 6h after oestrogen administration; any change in these effects at later times can be explained by an earlier eosinophil degranulation under the action of progesterone.

Effects of thyroid hormone on some uterine responses to estrogen

Uterine edema induced by 0.1 microgram 17 beta-estradiol (E2)/100 g BW, as well as uterine eosinophilia induced by 0.01, 0.1, 1, 10, and 30 micrograms E2/100 g BW, decrease in the presence of 20 micrograms T3 or T4/100 g BW in the immature rat. Estrogen binding by uterine eosinophils and the number of eosinophils in the blood also decrease with T3 or T4, suggesting an explanation for the findings in the uterus. Thyroid hormones alone or in the presence of 0.001, 0.01, 0.1 and 1 microgram E2/100 g BW, increase the uterine RNA content 7 h after administration compared with the same doses of E2 alone. This response is not associated with any further increase in the urine protein content. The results show a dissociation between the effects of estrogen on RNA or protein levels, which are decreased by thyroid hormones, and some early estrogenic responses (uterine edema and eosinophilia), which are decreased by thyroid hormones.

Effect of insulin and epinephrine on some early oestrogenic responses in the rat uterus

Oestradiol induces uterine eosinophilia and oedema, both in the intact immature rat and in the adult ovariectomized rat. These responses are decreased in ovariectomized-adrenalectomized adult rats, in adrenalectomized immature rats and in medullectomized immature rats. Pre-treatment with L-epinephrine restored both oestrogenic effects. Insulin inhibits oestrogen binding by uterine eosinophils and concurrently decreases oestrogen-induced uterine oedema and eosinophilia. These phenomena do not occur with inactive insulin. Insulin also induces blood eosinopaenia, suggesting an explanation for the findings in the uterus.