Androgen-dependent morphology of prostates and seminal vesicles in the Hershberger Assay: Evaluation of immunohistochemical and morphometric parameters

Cynomorium songaricum Rupr demonstrates phytoestrogenic or phytoandrogenic like activities that attenuates benign prostatic hyperplasia via regulating steroid 5-α-reductase

ETHNOPHARMACOLOGICAL RELEVANCE

Cynomorium songaricum Rupr. (CS) belongs to the genus of parasitic perennial flowering plants, mostly used in Chinese traditional medicine for benign prostatic hyperplasia (BPH) treatment. BPH is a chronic disease in men that both androgen and estrogen play a crucial role in promoting its development via their receptors. Previously we have showed that compounds from CS have the phytoestrogenic and/or phytoandrogenic activities that may have the potential suppressive effects on BPH, while the mechanism remains unclear.

AIM OF THE STUDY

In this study, we aim to investigate the effect of CS and its derived compounds: luteolin (LUT), gallic acid (GA), protocatechuic acid (PA) and protocatechualdehyde (Pra) on inhibition of rat BPH and proliferation of BPH-1 cell line respectively, and further uncover whether it is related with the phytoestrogenic and / or phytoandrogenic activities.

MATERIALS AND METHODS

Estradiol/testosterone (1:100) was subcutaneous injected to induce BPH in a castrated rat model, and CS was orally administrated for 45 days. Then the weights of the body and prostate were recorded, the pathogenesis changes of prostate were analyzed by Hematoxylin and eosin (H&E) and immunohistochemical (IHC). The levels of 17β-estradiol (E₂), testosterone, and dihydrotestosterone (DHT) from rats' serum were measured by enzyme-linked immunosorbent assay (ELISA). In vitro, human benign prostatic epithelial cell BPH-1 was cultured and treated with or without different CS compounds and DHT or E₂. MTT and CCK-8 assays were performed to detect the regulatory effects on cell proliferation. The expressions of PCNA, AR, ERα, ERβ, and steroid 5-α-reductases (SRD5A1 and SRD5A2) were further analyzed by western blotting upon treatment.

RESULTS

Treatment with CS significantly inhibited rat prostate enlargement, improved the pathological feature and reduced the thickness of smooth muscle layer. The up-regulated AR and ERα expressions and down-regulated ERβ in BPH rat prostate were significantly blocked after CS administration. Moreover, the enhanced values of E₂/testosterone and the level of DHT in serum were also strongly inhibited in CS group compared with those in BPH groups. In cellular level, LUT, GA, PA, or Pra significantly inhibited DHT- or E₂- induced BPH-1 cell proliferation and PCNA expressions. Consistently with the data in vivo, compounds from CS interfered the DHT or E₂-regulated AR, ERα and ERβ expressions in BPH-1 cells as well. Importantly, the dramatic increased SRD5A1 and SRD5A2 expressions were observed in BPH rat prostates and DHT or E₂-stimulated BPH-1 cells. However, treatment with CS in rat or with compounds isolated from CS in BPH-1 cells significantly blocked the induction of SRD5A1 and SRD5A2.

CONCLUSIONS

CS suppressed BPH development through interfering with prostatic AR, ERα/β, and SRD5A1/2 expressions, which provided evidence of CS for BPH treatment.

Expression of androgen receptor and cyclooxygenase-2 in the vesicular glands of castrated and intact goat

This study was conducted to demonstrate the effect of castration on the structure of vesicular glands of the Egyptian Nubian (Zaraibi) goat. Vesicular glands of castrated (n=4) and intact (n=6) goat were used for histological and immunohistochemical evaluations. In this study, we report the difference in cell specific expression of androgen receptor (AR) and cyclooxygenase-2 (COX-2) in the vesicular glands of castrated and intact goats. In both castrated and intact goats, the present study revealed no immunopositive cells for AR or COX-2 in the fibromuscular stroma meanwhile, AR and COX-2 containing immunoreactive cells were restricted only to the epithelium of the secretory acini of the vesicular gland. Such finding suggests androgen and COX-2 as important regulators for the growth and secretory activity of epithelial cells in the vesicular gland of goats. Overall, the vesicular gland of castrated goats showed significantly (P<0.05) lower AR and COX-2 immuno-expression than intact goats indicating that both AR and COX-2 are androgen dependent.

Differential Growth of the Reproductive Organs during the Peripubertal Period in Male Rats

In mammals, puberty is a process of acquiring reproductive competence, triggering by activation of hypothalamic kisspeptin (KiSS)-gonadotropin releasing hormone (GnRH) neuronal circuit. During peripubertal period, not only the external genitalia but the internal reproductive organs have to be matured in response to the hormonal signals from hypothalamic-pituitary-gonadal (H-P-G) axis. In the present study, we evaluated the maturation of male rat accessory sex organs during the peripubertal period using tissue weight measurement, histological analysis and RT-PCR assay. Male rats were sacrificed at 25, 30, 35, 40, 45, 50, and 70 postnatal days (PND). The rat accessory sex organs exhibited differential growth patterns compared to those of non-reproductive organs. The growth rate of the accessory sex organs were much higher than the those of non-reproductive organs. Also, the growth spurts occurred differentially even among the accessory sex organs; the order of prepubertal organ growth spurts is testis = epididymis > seminal vesicle = prostate. Histological study revealed that the presence of sperms in seminiferous tubules and epididymal ducts at day 50, indicating the puberty onset. The number of duct and the volume of duct in epididymis and prostate were inversely correlated during the experimental period. Our RT-PCR revealed that the levels of hypothalamic GnRH transcript were increased significantly on PND 40, suggesting the activation of hypothalamic GnRH pulse-generator before puberty onset. Studies on the peripubertal male accessory sex organs will provide useful references on the growth regulation mechanism which is differentially regulated during the period in andevrepogen-sensitive organs. The detailed references will render easier development of endocrine disruption assay.

Descrição morfológica e morfométrica da glândula vesicular de cobaias durante o desenvolvimento pós-natal

Glândulas vesiculares são essenciais para a reprodução, pois suas secreções afetam a função espermática. Cobaias (Cavia porcellus) são um excelente modelo experimental para estudo destas glândulas, contudo não existem dados morfológicos e morfométricos durante seu desenvolvimento. Neste estudo a morfologia (projeções das pregas (PP) e altura das células epiteliais (AE) da túnica mucosa) e a morfometria (massa (MG), volume (VG), comprimento (CG), largura das porções cranial (LCR), média (LM) e caudal (LCA)) das glândulas vesiculares foram determinadas em cobaios (N= 25) com uma (S1), três (S3), cinco (S5), oito (S8) e onze (S11) semanas de idade (N=5/grupo de idade). Em adição massa (MC), comprimento (CC) e altura (AC) corporais e o índice organo-somático (IOS) foram também determinados e o coeficiente de correlação (r) estabelecido entre as variáveis. As glândulas restringiam-se a cavidade pélvica e tinham seu interior repleto de uma massa semi-sólida e, após a S8, ocuparam também a cavidade abdominal e tiveram o conteúdo aumentado significativamente. A túnica mucosa era pregueada e forrada de um epitélio simples colunar. MC, CC e AC aumentaram continuamente com a idade. MG, VG, CG e LCA não se alteraram da S1 a S5 e aumentaram na S8; enquanto que MF, VG e LCA também aumentaram na S11. IOS e PP aumentaram na S8 e S11 e AE na S5, S8 e S11. Houve (r) significativo entre a idade, Bc e MFg,; IOS e MG na S8 e S11; idade e PP; idade e AE e entre PP e AE. Em conclusão, as glândulas vesiculares de cobaios seguiram o padrão morfológico observado em ratos e hamsters, mas diferiram em alguns aspectos de outros histricomorfos, podendo ser utilizadas como modelo experimental e seu desenvolvimento morfológico e morfométrico podem ser divididos em três fases: da S1 a S5, quando são discretos; da S6 a S8 de idade, quando são acentuados de maneira geral e após a S8, quando há incremento intenso da capacidade secretória.

Deletion of androgen receptor in the smooth muscle of the seminal vesicles impairs secretory function and alters its responsiveness to exogenous testosterone and estradiol

The seminal vesicles (SVs), like much of the male reproductive tract, depend on androgen-driven stromal-epithelial interactions for normal development, structure, and function. The primary function of the SVs is to synthesize proteins that contribute to the seminal plasma and this is androgen dependent. However, the cell-specific role for androgen action in adult SVs remains unclear. This study analyzed the SV in mice with targeted ablation of androgen receptors specifically in smooth muscle cells (PTM-ARKO) to determine in vivo whether it is androgen action in a subset of the SV stroma, the smooth muscle cells, that drives epithelial function and identity. These mice have significantly smaller SVs in adulthood with less smooth muscle and reduced epithelial cell height. Less epithelial cell proliferation was observed in adult PTM-ARKO SVs, compared with controls, and production of seminal proteins was reduced, indicating global impairment of epithelial cell function in PTM-ARKO SVs. None of these changes could be explained by altered serum testosterone or estradiol concentrations. We also demonstrate altered SV responsiveness to exogenous testosterone and estradiol in PTM-ARKO mice, indicating that smooth muscle androgen receptors may limit the SV epithelial proliferative response to exogenous estrogens. These results therefore demonstrate that the smooth muscle cells play a vital role in androgen-driven stromal-epithelial interactions in the SV, determining epithelial cell structure and function as well as limiting the SV epithelial proliferative response to exogenous estrogens.

Matrix metalloproteinase (MMP)-2 and MMP-9 activity and localization during ventral prostate atrophy and regrowth

Matrix metalloproteinses (MMPs) are enzymes involved in prostatic development, growth, disease-induced tissue remodelling and secretory fluid. Although the prostate function depends upon androgen regulation, the relationship between MMPs and androgen has not been well established. Here, we evaluated MMP-2 and MMP-9 gelatinolytic activity in association with tissue localization during ventral prostate atrophy and regrowth induced by testosterone replacement (TR). Adult male Wistar rats were divided into three experimental groups: control, castrated (CS) and TR 21 days after castration. Ventral prostate (VP) was excised at 3, 5, 7 and 21 days after castration in CS group, and at 3, 5, 7 and 10 days after TR (4 mg/kg/day) in TR group. The VP was dissected, weighed and processed for histology, immunohistochemistry, ultrastructure and zymography analyses. Castration elicited the typical parenchymal atrophy and stromal condensation. TR induced intense epithelial growth towards the stromal space to restore the prostate histoarchitecture. MMP-2 and MMP-9 immunostaining presented intense reaction in CS and TR groups, mainly in the epithelial and endothelial cells. After TR, a strong immunoreaction for MMP-2 was observed in the activated stromal fibroblasts. Zymography showed that MMP-2 and MMP-9 activity, mainly the active form, increased after castration. In contrast, TR induced an additional increase in MMP-2 activity, but not in MMP-9. In conclusion, the overall behaviour of MMP-2 and MMP-9 within the prostate under androgen handling is highly complex, as each glandular compartment and cell type is affected differently by the androgenic status. Prostate regrowth appears to involve a more effective participation of MMP-2 in both epithelial and stromal compartments, while MMP-9 plays a major role in the late prostate atrophy and early regrowth.

Cypermethrin effects on the adult mice seminal glands

The insecticide cypermethrin acts upon the sodium channels. Their effects over animal health are not understood. Here, the effects of cypermethrin on the seminal glands (SGs) are studied (1/5 DL50 i.p.). Forty-five adult mice (CF1) were distributed in three groups: (1) untreated, (2) vehicle (oil), and (3) experimental (cypermethrin in oil). The animals were sacrificed at 1 and each 8.6 days. The SGs were processed for histology: Haematoxylin/P.A.S, Thyonin (0.6%) and Immunohistochemistry (Ki-67). In the SGs was quantified: the epithelium height, mastocytes, and cell proliferation. In the results, cypermethrin exerts an intense effect on epithelium height and cell proliferation. A net increase of both parameters was observed at 24 h (p0.05). However, the mastocytes increased drastically and progressively during the experimental period (p0.05). Then, the effects have acute manifestations, which would be responsible for the potential changes in the male's reproductive potentiality.

Tropaeolum tuberosum (Mashua) reduces testicular function: effect of different treatment times

Tropaeolum tuberosum Ruiz & Pavon, along with other several species, is an edible-tuber crop that grows in the Andean region. Folk medicine describes the use of mashua to reduce reproductive function in men. The present study aimed to evaluate the effect of mashua (1 g kg(-1)) on sperm production in rats during 7, 12, 21 and 42 days of treatment. The following parameters were assessed: reproductive organ weights, spermatid count and daily sperm production (DSP), sperm count in epididymis and sperm transit and serum testosterone levels. Freeze-dried extract of mashua had 3.7 g 100 g(-1) of benzyl glucosinolate. Mashua-treated rats showed a reduction in testicular spermatid number and DSP from day 12 to day 42; meanwhile, the effect of mashua was noted in epididymal sperm count after 12 and 42 days of treatment. In addition, epididymal sperm transit time was delayed at day 7 and it was accelerated on days 12 and 21 of treatment. No differences in serum testosterone levels were found between rats treated with vehicle and mashua after 42 days of treatment. Finally, mashua reduces testicular function after one spermatogenic cycle by reducing spermatid and sperm number, DSP and epididymal sperm transit time.

Red maca (Lepidium meyenii) reduced prostate size in rats

BACKGROUND

Epidemiological studies have found that consumption of cruciferous vegetables is associated with a reduced risk of prostate cancer. This effect seems to be due to aromatic glucosinolate content. Glucosinolates are known for have both antiproliferative and proapoptotic actions. Maca is a cruciferous cultivated in the highlands of Peru. The absolute content of glucosinolates in Maca hypocotyls is relatively higher than that reported in other cruciferous crops. Therefore, Maca may have proapoptotic and anti-proliferative effects in the prostate.

METHODS

Male rats treated with or without aqueous extracts of three ecotypes of Maca (Yellow, Black and Red) were analyzed to determine the effect on ventral prostate weight, epithelial height and duct luminal area. Effects on serum testosterone (T) and estradiol (E2) levels were also assessed. Besides, the effect of Red Maca on prostate was analyzed in rats treated with testosterone enanthate (TE).

RESULTS

Red Maca but neither Yellow nor Black Maca reduced significantly ventral prostate size in rats. Serum T or E2 levels were not affected by any of the ecotypes of Maca assessed. Red Maca also prevented the prostate weight increase induced by TE treatment. Red Maca administered for 42 days reduced ventral prostatic epithelial height. TE increased ventral prostatic epithelial height and duct luminal area. These increases by TE were reduced after treatment with Red Maca for 42 days. Histology pictures in rats treated with Red Maca plus TE were similar to controls. Phytochemical screening showed that aqueous extract of Red Maca has alkaloids, steroids, tannins, saponins, and cardiotonic glycosides. The IR spectra of the three ecotypes of Maca in 3800-650 cm (-1) region had 7 peaks representing 7 functional chemical groups. Highest peak values were observed for Red Maca, intermediate values for Yellow Maca and low values for Black Maca. These functional groups correspond among others to benzyl glucosinolate.

CONCLUSIONS

Red Maca, a cruciferous plant from the highland of Peru, reduced ventral prostate size in normal and TE treated rats.