Prolactin promotes a partial recovery from the atrophy of both male and female gerbil prostates caused by castration.

BACKGROUND: The male and female prostates are controlled by steroid hormones, suffering important morphological and physiological changes after castration. Prolactin is involved in the regulation of the male prostate, having already been identified in the tissue, acting through its receptor PRLR. In the Mongolian gerbil, in addition to the male prostate, the female prostate is also well developed and active in its secretion processes. The aim of the present study was to evaluate the effects of exposure to exogenous prolactin in the prostate of both intact and castrated male and female gerbils in order to establish if prolactin administration can sustain prostate cell activity in conditions of sexual hormone deprivation. METHODS: The morphological analyses were performed by biometric analysis, lesion histological analysis and morphometric-stereological aspects. In addition, immune-cytochemical tests were performed for prolactin and its receptor, as well as for the receptors of androgen and oestrogen and serum prolactin dosage. All data were submitted to ANOVA or Kruskal-Wallis tests for comparison between groups. P < 0.05 was considered to be statistically significant. RESULTS: The results showed a strong influence of prolactin on the morphology of the prostate, with the development of important epithelial alterations, after only 3 days of administration, and an expressive epithelial cell discard process after 30 days of administration. Prolactin acts in synergy with testosterone in males and mainly with oestrogens in females, establishing different steroid hormonal receptor immunoreactivity according to sex. It was also demonstrated that prolactin can assist in the recovery from some atrophic effects caused in the gland after castration, without causing additional tissue damage. CONCLUSIONS: The prolactin and its receptor are involved in the maintenance of the homeostasis of male and female gerbils, and also cause distinct histological alterations after exogenous exposure for 3 and 30 days. The effects of prolactin are related to its joint action on androgens and oestrogens and it can also assist in the recovery from the atrophic effects of castration.

Ovariectomy increases the phenotypic plasticity of the female prostate epithelium in the Mongolian gerbil (Meriones unguiculatus).

The female prostate is a reproductive gland that typically presents a morphology similar to that of the male gland and is highly developed in female Mongolian gerbils. Two main cell populations compose the epithelium gland: basal and secretory luminal cells. However, during postnatal development, diverse secretory cell phenotypes are distributed among the typical ones. Prostate homeostasis is under the control of sexual hormones, such as oestrogen and progesterone. After hormonal deprivation the female gland undergoes several morphophysiological changes. The objective of this study was to identify and characterise, structurally and ultrastructurally, the cellular heterogeneity of the female prostate epithelium in normal conditions and after ovariectomy. Histological routine stains, such as haematoxylin-eosin, periodic acid-Schiff and silver impregnation, as well as immunocytochemical techniques were used to enable identification of the different cell types. Some secretory cells types were identified and characterised as mucinous, basophil, clear, ciliated, droplet, spumous and neuroendocrine cells. Population tally data showed that the hormonal suppression caused by ovariectomy resulted in a decrease in the proportions of basophil and clear cells and an increase in spumous cells. Thus, the secretory epithelial cells of the female gerbil prostate are not morphologically and functionally uniform, presenting a phenotypical plasticity according to the hormonal environment in which they operate.

Acute exposure to bisphenol A and cadmium causes changes in the morphology of gerbil ventral prostates and promotes alterations in androgen-dependent proliferation and cell death.

Bisphenol A (BPA) and cadmium (Cd) are environmental pollutants that are implicated in potential reproductive effects, including damage to the prostate gland. Their action during puberty requires analysis to determine the relationship of these compounds with the testosterone peak that occurs during this phase. This study evaluated whether exposure to BPA and Cd during puberty can cause changes in the morphology, proliferation and cell death and androgen receptor (AR) immunostaining of the ventral prostates of normal and castrated male gerbils (Meriones unguiculatus), considering an acute exposure to the chemicals and evaluation after short (52d) and long (120d) periods. Generally, morphometric-stereological results demonstrated that administration of BPA and Cd (individually or in combination) increased epithelial height, smooth muscle layer (SML) thickness and nuclear area and perimeter, and that these parameters were reduced in castrated animals. In addition, these groups showed important inflammatory processes but not prostate lesions. The proliferation/death rates of prostatic cells obtained by PCNA and TUNEL immunostaining demonstrated increased cell death in the 52d groups; in contrast, the gland acquired a more proliferative nature in the 120d groups. AR immunostaining showed that BPA and Cd compounds interact with ARs in different ways depending on the evaluated period and the hormonal profile of the animal. We conclude that BPA and cadmium are important agents in changing the morphology, proliferation and death of prostatic cells, in addition to interacting with ARs in different patterns. © 2015 Wiley Periodicals, Inc. Environ Toxicol 32: 48-61, 2017.

Actions of oestradiol and progesterone on the prostate in female gerbils: reversal of the histological effects of castration.

The female prostate is a functionally active gland in several mammalian species, including humans and rodents. Investigations of prostate morphophysiology during the phases of the oestrous cycle have shown that the female prostate is influenced by fluctuations in serum concentrations of oestradiol (E2) and progesterone (P4). The aim of the present study was to evaluate the effect of combined prolonged administration of E2 and P4 on the prostate in ovariectomised female gerbils. Ovariectomy caused atrophy and decreased glandular secretory activity. Administration of E2 and P4 (0.1mgkg(-1) diluted in 0.1mL of mineral oil, every 48h over 30 days) resulted in a recovery of overall prostate structure, as evidenced by increased epithelial height, mass and prostatic secretory activity, without leading the appearance of significant lesions. Evaluation of androgen receptor (AR) expression revealed increased immunoreactivity in the E2+P4-treated group. Immunostaining for oestrogen receptor (ER) α was decreased in the castrated groups, but increased in the group subjected to hormone treatment. There were no significant differences in ERß immunoreactivity among the groups. Assessment of cell proliferation revealed greater immunoreactivity in the treated group. Together, the results indicate that the interaction between E2 and P4 may be responsible for maintaining female prostate gland histophysiology.

Annexin-A1 peptide down-regulates the leukocyte recruitment and up-regulates interleukin-10 release into lung after intestinal ischemia-reperfusion in mice.

BACKGROUND: Intestinal ischemia/reperfusion (IR) injury is a serious and triggering event in the development of remote organ dysfunction, from which the lung is the main target. This condition is characterized by intense neutrophil recruitment, increased microvascular permeability. Intestinal IR is also responsible for induction of adult respiratory distress syndrome, the most serious and life-threatening form of acute lung injury. The purpose of this study was to investigate the effect of annexin-A1 protein as an endogenous regulator of the organ remote injury induced by intestinal ischemia/reperfusion. Male C57bl/6 mice were subjected to intestinal ischemia, induced by 45 min occlusion of the superior mesenteric artery, followed by reperfusion. RESULTS: The intestinal ischemia/reperfusion evoked a high intensity lung inflammation as indicated by the number of neutrophils as compared to control group. Treatment with annexin-A1 peptidomimetic Ac2-26, reduced the number of neutrophils in the lung tissue and increased its number in the blood vessels, which suggests a regulatory effect of the peptide Ac2-26 in the neutrophil migration. Moreover, the peptide Ac2-26 treatment was associated with higher levels of plasma IL-10. CONCLUSION: Our data suggest that the annexin-A1 peptidomimetic Ac2-26 treatment has a regulatory and protective effect in the intestinal ischemia/reperfusion by attenuation of the leukocyte migration to the lung and induction of the anti-inflammatory cytokine IL-10 release into the plasma. The anti-inflammatory action of annexin-A1 and its peptidomimetic described here may serve as a basis for future therapeutic approach in mitigating inflammatory processes due to intestinal ischemia/reperfusion.

Progesterone restores the female prostate activity in ovariectomized gerbil and may act as competitor of testosterone in intraprostatic environment.

AIMS: Little is known about the effect of progesterone on gerbil female prostate. It is known that normal oscillation in the progesterone and estradiol levels during the estrous cycle phases influence the morphophysiology of this gland. The present study aims to evaluate the isolated effect of prolonged administration of progesterone combined or not with testosterone on the prostate of ovariectomized female gerbil. MAIN METHODS: To observe the morphological changes caused by castration in the prostate of different groups stereologic analyses of all prostate compartments, analysis of nuclear area and perimeter, and morphometric measurements of epithelial and smooth muscle cells layers were used. In addition, immunocytochemistry was performed to investigate the distribution of the androgen, estrogen alfa and beta and progesterone receptors in different prostatic compartments. KEY FINDINGS: This study demonstrated that both treatments partially recovered the structure of the gland. In the group treated with progesterone plus testosterone a higher incidence of epithelial and stromal disorders occurred, besides the absence of secretory activity. Thus, treatment only with progesterone showed better results in the restoration of glandular homeostasis mainly seen by the regulation of the secretory activity. SIGNIFICANCE: Collectively, the findings of this study indicate that progesterone may have a significant role on the maintenance of prostate morphophysiology, and showed an interesting evidence of hormonal competition between progesterone and testosterone.

Effects of exposure to estradiol and estradiol plus testosterone on the Mongolian gerbil (Meriones unguiculatus) female prostate.

The female prostate is a differentiated organ found in several mammal species, including humans and rodents. This gland has been related to important functions on female reproductive biology. Although the factors, which regulate prostate's development and activity are not well known, its functionality has been related to steroid hormones. It is well established that cyclic changes of estradiol and progesterone levels promote histophysiological adaptations of the whole female body. In contrast, only a few is found about those adaptations in female prostate. Thus, this study aimed to evaluate the effect of estradiol and estradiol + testosterone association on gerbil female prostate in order to verify, which hormonal associations are necessary to its homeostasis. For this, adult females had the ovaries surgically removed. After recovering, they received estradiol and estradiol + testosterone doses through 30 days, each 48 h. The prostatic tissue underwent morphological and morphometric-estereological analysis. Hormonal restriction caused great gland involution and decreased secretory activity, aspects that were reverted by exposure to estradiol and estradiol + testosterone. However, these hormones were not able to re-establish the normal prostate histoarchitecture. The immunoreaction of steroid receptors (ER-α, ER-ß, and AR) responded differently among the experimental and control groups, and PCNA assay showed a decrease in epithelial cell proliferation within groups that had hormone privation. Therefore, we conclude that estradiol and testosterone are able to influence prostate morphophysiology and the maintenance of gland homeostasis depends on a balance among these and other hormones.