Protective effect of the association of curcumin with piperine on prostatic lesions: New perspectives on BPA-induced carcinogenesis

Bisphenol A (BPA) is a chemical agent which can exert detrimental effects on the male reproductive system, especially the prostate gland. In this study we described the efficacy of the dietary agent curcumin, alone or combined with piperine, to suppress the impact of BPA on the prostate. Adult gerbils were divided into nine experimental groups (n = 7 each group), regarding control (water and oil), exposed to BPA (50 μg/kg/day in water) or curcumin (100 mg/kg) and/or piperine (20 mg/kg). To evaluate the effects of the phytotherapic agents, the other groups received oral doses every two days, BPA plus curcumin (BCm), piperine (BP), and curcumin + piperine (BCmP). BPA promoted prostatic inflammation and morphological lesions in ventral and dorsolateral prostate lobes, associated with an increase in androgen receptor-positive cells and nuclear atypia, mainly in the ventral lobe. Curcumin and piperine helped to minimize these effects. BPA plus piperine or curcumin showed a reduction in nuclear atypical phenotype, indicating a beneficial effect of phytochemicals. Thus, these phytochemicals minimize the deleterious action of BPA in prostatic lobes, especially when administered in association. The protective action of curcumin and piperine consumption is associated with weight loss, anti-inflammatory potential, and control of prostate epithelial cell homeostasis.

Hormone receptor expression in aging mammary tissue and carcinoma from a rodent model after xenoestrogen disruption

AIMS

Hormone receptors are the main markers applied for prognosis of breast cancer subtypes. Among modulators, exogenous chemical agents known as endocrine disruptors interact with certain receptors, triggering molecular pathways or increasing their expression. Bisphenol A (BPA), a xenoestrogen, interacts with several hormone receptors. Thus, our aim was to characterize the hormone receptor status in the mammary gland (MG) of aged female Mongolian gerbils exposed to BPA in pregnancy and lactation.

METHODS

We evaluated the expression of receptors for estrogens (ERα and ERβ), progesterone (PR), prolactin (PRL-R), HER2/ErbB2, and androgen (AR) in normal and hyperplastic mammary tissue and in carcinomas developed after BPA exposure.

KEY FINDINGS

BPA-exposed MG presented increased ERα, whereas ERβ, PR, and PRL-R showed lower expression. AR and HER2/ErbB2 showed similar expression in normal and hyperplastic tissue from control, vehicle, and BPA groups. Both receptors were found in cytoplasm and nucleus in BPA-induced carcinoma. We demonstrate the presence of EZH2 expression, an epigenetic and epithelial-mesenchymal transition (EMT) marker, with a high H-score in BPA-exposed MG, which was associated with poor prognosis of cancer. Co-localization of ERα and EZH2 was present in normal and carcinoma features, corroborating the installation of ERα-positive mammary cancer associated with the EMT process. Enhanced EZH2 in BPA-exposed mammary tissue could decrease ERβ expression and promote tumorigenesis progress through HER2/ErbB2.

SIGNIFICANCE

The present study proposes the Mongolian gerbil as an experimental model for mammary carcinogenesis studies, based on BPA disruption that triggers a phenotype of increased ERα/HER2 positivity and depletion of ERβ/PR expression.

Therapeutic effects of β-caryophyllene on proliferative disorders and inflammation of the gerbil prostate

BACKGROUND

The prostate is susceptible to changes in androgen levels, which can play an important role in the development of Benign Prostatic Hyperplasia (BPH). Natural compounds have beneficial properties for organisms and can be an important therapeutic strategy in the treatment of diseases. β-Caryophyllene (BCP) is a phytocannabinoid present in several medicinal and food plants species and has shown beneficial effects in different organs. However, little is known about its effects on the prostate. The present study seeks to evaluate the effects of exposure to BCP on the morphophysiology of the ventral prostate of adult gerbils supplemented with testosterone.

METHODS

Animals were distributed into four groups (n = 8/group): Intact control (C); β-Caryophyllene (BCP): β-Caryophyllene (50 mg/kg/day); Testosterone (T): animals received subcutaneous injections of Testosterone Cypionate (3 mg/Kg), on alternate days, for one month and were euthanized 30 days supplementation ended; Testosterone and β-Caryophyllene (TBCP): animals were exposed to testosterone cypionate (3 mg/Kg) to induce hyperplastic alterations followed by daily BCP (50 mg/kg). Morphological, biometric, immunohistochemical, and serological analyses were performed.

RESULTS

Proliferative disorders and inflammatory foci were present in the ventral prostate of all experimental groups. An increase in the multiplicity of benign intraepithelial neoplasm and subepithelial inflammatory foci was observed in T group. The incidence of intraluminal inflammatory foci and microinvasive carcinoma was verified only in the T group. Cellular rearrangement and tissue remodeling occurred in the prostate of groups exposed to phytocannabinoids. A reduction was observed in the frequency of PHH3 and Cox2 markers in the prostatic epithelium of TBCP in comparison with T. A decrease in F4/80 and CD163 positive macrophages were also observed in the prostatic stroma of the TBCP group in comparison with T. The results suggest that BCP had favorable effects on BPH, reducing the proliferation and frequency of some inflammatory cells.

CONCLUSION

BCP impacts the tissue remodeling process in the premalignant prostate environment and that the use of this phytocannabinoid can have a promising effect in the handling of BPH.

Impact of perinatal bisphenol A and 17β estradiol exposure: Comparing hormone receptor response

Hormonal regulation controls mammary gland (MG) development. Therefore some hormone-related factors can disrupt the early phases of MGs development, making the gland more susceptible to long term modifications in its response to circulating hormones. Endocrine disruptors, such as bisphenol A (BPA), are able to cause alterations in hormone receptor expression, leading to changes in the cell proliferation index, which may expose the tissue to neoplastic alterations. Thus, we evaluated the variations in hormone receptor expression in the MG of 6-month old Mongolian gerbils exposed to BPA and 17β estradiol during the perinatal period. Receptors for estrogen alpha (ERα), beta (ERβ), progesterone (PGR), prolactin (PRL-R), and co-localization of connexin 43 (Cx43) and ERα in gerbils were analyzed, and serum concentrations of estradiol and progesterone were assessed. No alterations in body, liver, and ovary-uterus complex weights were observed. However, there was an increase in epithelial ERα expression in the 17β estradiol (E2) group and in PGR in the BPA group. Although immunohistochemistry did not show alterations in ERβ expression, western blotting revealed a decrease in this protein in the BPA group. PRL-R was more present in epithelial cells in the vehicle control (VC), E2, and BPA groups in comparison to the intact control group. Cx43 was more frequent in E2 and BPA groups, suggesting a protective response from the gland against possible malignancy. Serum concentration of estradiol reduced in VC, E2, and BPA groups, confirming that alterations also impacts steroid levels. Consequently, perinatal exposure to BPA and the reference endogenous estrogen, 17β estradiol, are able to increase the tendency of endocrine disruption in MG in a long term manner, since repercussions are observed even 6 months after exposure.

Perinatal exposure to bisphenol A impacts in the mammary gland morphology of adult Mongolian gerbils

The endocrine disruptive effects caused by bisphenol A (BPA) are well known. Despite this, to date, evaluation of its long term effects is limited, meaning that there is still much to be unveiled in terms of alterations caused by perinatal exposure to BPA. Our aim was to determine if perinatal exposure to two different doses of BPA causes long term morphological and molecular alteration effects in the mammary gland (MG). We evaluated MG from Mongolian gerbil offspring exposed perinatally (during gestation and lactation) to 50 or 5000 μg/kg/day BPA. At 90 days of age the animals were subjected to a single dose of N-nitroso-N-methylurea in order to mimic a carcinogenic environment. At 6 months of age, animals in estrous were euthanized for morphological evaluation of the MGs. The MG architecture presented considerable changes in terms of detached epithelial cells, inflammation, glandular hyperplasia, and collagen fiber deposition. Furthermore, a higher index of epithelial cell proliferation was detected in comparison to the intact control group. In addition, we verified a higher molecular expression of EZH2 in the vehicle treated group, indicating that corn oil applied alone can alter the expression of this epigenetic biomarker. In conclusion, BPA perinatal exposure promotes significant changes in glandular cytoarchitecture and increases glandular epithelium proliferation rate, leading to the retention of stem-like properties. This event could compromise the fate and differentiation potential of mammary epithelium.

Reproductive Aspects of Chagas Disease Vectors: Evidence of Transcriptional Activity during the Nucleolar Persistence Phenomenon in the Spermatogenesis of Triatomines

The subfamily Triatominae currently consists of 154 species, most of them being of great importance for public health because they are considered potential vectors of the protozoan Trypanosoma cruzi, the etiologic agent of Chagas disease. In addition to their epidemiological importance, these insects are considered important biological models for cell studies because they have peculiar characteristics in their cells, for example, persistence of the nucleolus during spermatogenesis. This phenomenon is characterized by the presence of the nucleolus or nucleolar corpuscles during all phases of meiosis. To date, all knowledge is restricted to the study of the presence/absence of the nucleolus during the triatomine meiosis, so the present work aimed to analyze if this persistent nucleolar material has transcriptional activity. Analysis of the meiotic metaphases of Rhodnius montenegrensis and Panstrongylus megistus by using fluorochrome acridine orange made it possible to characterize the presence of RNA in the nucleolar material. Thus, it was demonstrated, for the first time, that the persistent nucleolar material during triatomine meiosis is transcriptionally active, supporting the hypothesis of the relationship between nucleolar persistence during meiosis of these insects and the formation of the chromoid body, an organelle responsible for the support of all transcriptional activities during spermiogenesis.

Budding process during the organogenesis of the ventral prostatic lobe in Mongolian gerbil

The prostate is a mammalian gland that shows a complex process of organogenesis. Here, a morphological study to characterize the organogenesis of the ventral prostate lobe in male gerbils was conducted. The urogenital sinus (UGS) was dissected out and processed for paraffin embedding. Histological sections were subjected to cytochemical, immunofluorescence, immunohistochemical, and three-dimensional reconstruction techniques. We found that the first ventral buds emerged from the ventral urethral epithelium between the days 20 and 21 of prenatal life, reaching the ventral mesenchymal pad and initiating the branching process on the first day of postnatal life. The buds presented a V-shaped elongation, suggesting that the smooth muscle layer (SML) plays an important role during budding events. Indeed, whereas the androgen receptor (AR) was preferentially found in the UGS mesenchyme (UGM), estrogen receptor alpha (ERα) was localized in both the UGM and in the emerging buds. This study characterized the morphological aspects of the budding process in a different rodent from rat and mice, serving as a new model for future studies on developmental biology of the prostate.

MMP-2 and TIMP-2 in the prostates of male and female mongolian gerbils: effects of hormonal manipulation

TIMPs in the prostates of male and female gerbils and evaluated the effects of testosterone on the expression of these enzymes. Ventral prostates from male gerbils that were either intact or had been castrated for 7 or 21 days, along with prostates from female gerbils that were either intact or had been treated with testosterone for 7 or 21 days, were submitted to histological, stereological and immunohistochemical analyses. Stereology of prostatic components showed significant alterations of tissue compartments in the ventral male prostate after castration, especially after 21 days, with a significant increase in stroma. Administration of testosterone led to disorganization in the female prostate, with a significant increase in collagen fibers and smooth muscle cells after 21 days, along with the development of epithelial lesions such as PINs. MMP-2 increased after 21 days of castration in males; however, the TIMP-2 immunoreaction for this group was weak or absent. In females, the expression of MMP-2 appeared to decrease after 7 days of treatment with testosterone, but after 21 days, both epithelium and stroma showed a stronger reaction for MMP-2 than the controls. The expression of TIMP-2 in the treated females was similar to its expression in the castrated males. We conclude that the distribution of MMPs and TIMPs in both male and female prostates is altered by androgen manipulation, but the mechanism of stromal regulation appears to be distinct between genders because both the lack of T in castrated males and the excess levels of T in treated females lead to the same effect.

Age-related histopathological lesions in the Mongolian gerbil ventral prostate as a good model for studies of spontaneous hormone-related disorders

The Meriones unguiculatus (Mongolian) gerbil has demonstrated significant prostatic responses to hormonal treatments, and to drugs against human prostatic hyperplasia. Spontaneous neoplasia develops in the older animals. Thirty gerbils (age 18 months) were divided into non-affected and prostatic lesion bearers and the prostate lesions were evaluated morphologically, immunohistochemically and quantitatively. The most frequent changes were in epithelial sites and, namely prostatic intraepithelial neoplasias, microinvasive carcinomas and adenocarcinomas. In the stromal compartment, cellular hyperplasia, when verified, was always associated with the sites of anomalous epithelium. Additionally, larger deposition of collagen fibrils, generating stromal fibrosis, was found in all the old gerbils analysed. The quantitative analysis showed that prostatic tissue proportions differed in altered areas, being specific for each lesion type. Isolated nuclear and nucleolar parameters were not effective in diagnosing the malign potential of lesions. However, the cellular proliferation and death indexes indicated larger cellular turnover in invasive lesions such as carcinomas. With these analyses, it could be verified that old gerbils present high propensity to develop spontaneous prostate changes and this may aid in a better understanding of the biological behaviour of human prostate cancer.

Exposure of young rats to high estrogen doses leads to degeneration of elongated spermatids

Single high doses of estrogen (35 mg/kg body weight) were administered to young rats aiming to exacerbate its effects on germ cell populations. The short-term (1 week) and medium-term (7 weeks) consequences of this estrogenic treatment (ET) on the testis were evaluated using light and electron microscopies, quantitative methods and TUNEL reaction. Short-term ET led to 50% atrophy of the testis, however, in the medium term the gonado-somatic index was recovered. No histopathological alterations were found at seminiferous epithelium except for short-term severe degeneration of elongated spermatids (EL) and low frequency of these cells in both time intervals. Two morphologically distinct patterns of degeneration were observed: (1) clusters of EL which were TUNEL-negative and exhibited bizarre appearance and nuclear fragmentation, (2) isolated apoptotic EL within the cytoplasm of Sertoli cells (SC). Both degenerative phenomena were more frequent in stages III-VIII of seminiferous cycle, whereas at stages I and II only coiling of flagellum was observed. One week after ET, small amounts of EL were detected in stages IX-XII, suggesting spermiation failure. Signs of functional SC damage such as an accumulation of myelin-like inclusions in their cytoplasm were observed in the short but not medium-term. However, the apoptotic rates still remained five times higher and the number of elongated spermatids was three-fold lower. Our data indicate that exposure to a high dose of estrogen around puberty has stage-specific effects on the testis and causes massive degeneration of elongated spermatids.