大豆黄酮对睾酮诱导的大鼠前列腺增生预防作用的实验研究

目的:探讨大豆黄酮对雄激素诱导的大鼠前列腺增生的预防作用。方法:成年雄性SD大鼠36只,随机分为Ⅰ~Ⅵ组,每组6只。Ⅰ组(正常对照组)、Ⅱ组(模型组)给予1ml生理盐水、Ⅲ~Ⅵ组(低、中、高大豆黄酮组及阳性对照组)分别给予2、20、100mg/kg大豆黄酮及0.1mg/kg己烯雌酚灌胃,1次/d,连续90d。从第91d开始,Ⅱ~Ⅵ组分别皮下注射丙酸睾酮(7.5mg/kg,1次/d,连续10d)诱导前列腺增生。观测各组大鼠前列腺湿重、前列腺指数;HE染色观察前列腺组织变化情况;免疫组化方法检测大鼠前列腺内雌激素受体α、β(ERα、ERβ)表达的变化。结果:与模型组相比,低、中、高大豆黄酮组及阳性对照组的前列腺湿重与前列腺指数均有显著降低(P<0.05或P<0.01)。中、高剂量大豆黄酮组大鼠前列腺增生减轻更明显,表现为上皮变薄,腺腔内分泌物明显减少,间质减少。ERα在模型组的表达与其余各组无明显差异;ERβ在各剂量大豆黄酮组与模型组相比明显减少。结论:大豆黄酮对睾酮诱导的前列腺增生有一定预防作用。     

NAD(P)H‐quinone oxidoreductase 1 silencing aggravates hormone‐induced prostatic hyperplasia in mice

NAD(P)H‐quinone oxidoreductase 1 (NQO1) is a highly inducible flavoprotein known to involve in various cellular defence mechanisms. In this study, we explored whether NQO1 deletion affects hormone‐induced prostatic hyperplasia. Testosterone propionate (3 mg/kg, IP) was injected into wild‐type (WT) and NOQ1 knockout C57BL/6 mice (NQO1^?/?) for 14 consecutive days, and the samples were collected for biological and histochemical studies. The testosterone‐treated NQO1^?/? showed about 140% higher prostate weight than the testosterone‐treated WT, with enhanced connective tissue and hyperplastic glands formations. However, increased dihydrotestosterone level after testosterone treatment was not significantly different between the WT and NQO1^?/?. In contrast, the enhanced nuclear expression of proliferating cell nuclear antigen in NQO1^?/? prostate confirmed aggravated prostatic hyperplasia in NQO1^?/?. Moreover, the expression of heat shock protein (HSP) 90‐α was markedly increased in the NQO1^?/?, and this was supported by increased testosterone‐induced nuclear androgen receptor expression in NQO1‐silenced LNCaP cells. Testosterone‐induced prostate‐specific antigen expression was not reversed in NOQ1‐silenced cells after finasteride treatment. Although the exact role of NQO1 in prostatic hyperplasia remains unclear, the hyperplasia exacerbation due to NQO1 deletion might be independent of type 2 5α‐reductase and might be related to enhanced androgen receptor affinity due to enhanced HSP90‐α expression.     

Antagonistic effect of Lepidium meyenii (red maca) on prostatic hyperplasia in adult mice

The plants from the Lepidium gender have demonstrated to have effect on the size of the prostate. Lepidium meyenii (Maca) is a Peruvian plant that grows exclusively over 4000 m above sea level. The present study was designed to determine the effect of red maca (RM) in the prostate hyperplasia induced with testosterone enanthate (TE) in adult mice. Prostate hyperplasia was induced by administering TE, and then these animals ( n  = 6, each group) were treated with RM or Finasteride (positive control) for 21 days. There was an additional group without prostate hyperplasia (vehicle). Mice were killed on days 7, 14 and 21 after treatment with RM. Testosterone and oestradiol levels were measured on the last day of treatment. Prostatic stroma, epithelium and acini were measured histologically. RM reduced prostate weight at 21 days of treatment. Weights of seminal vesicles, testis and epididymis were not affected by RM treatment. The reduction in prostate size by RM was 1.59 times. Histological analysis showed that TE increased 2-fold the acinar area, effect prevented in the groups receiving TE + RM for 14 ( P  < 0.05) and 21 ( P  < 0.05) days and the group receiving TE + Finasteride for 21 days ( P  < 0.05). TE increased prostatic stroma area and this effect was prevented by treatment with RM since 7 days of treatment or Finasteride. The reduction in prostatic stroma area by RM was 1.42 times. RM has an anti-hyperplastic effect on the prostate of adult mice when hyperplasia was induced with TE acting first at prostatic stromal level.     

Protective effects of Fumaria parviflora L. on lead‐induced testicular toxicity in male rats

In recent years, the clinical importance of herbal drugs has received considerable attention in reducing free radical‐induced tissue injury. Oxidative stress has been proposed as a possible mechanism involved in lead toxicity that causes reproductive system failure in both human and animals. Fumaria parviflora L., a traditional herb, has been used to cure various ailments in Persian folk medicine. This study was carried out to investigate whether ethanolic extract of F. parviflora leaves could protect the male rats against lead‐induced testicular oxidative stress. Adult Wistar rats were treated with 0.1% lead acetate in drinking water with or without 200 mg kg day^?1 F. parviflora extract via gavage for 70 days. Lead acetate treatment resulted in significant reduction in testis weight, seminiferous tubules diameter, epididymal sperm count, serum testosterone level, testicular content of superoxide dismutase (SOD) and glutathione peroxidase (GPx). Moreover, significant elevation was observed in content of malondialdehyde (MDA) in lead‐treated rats. However, co‐administration of F. parviflora extract showed a significant increase in selected reproductive parameters in lead‐treated rats. The results indicated that ethanolic extract of F. parviflora leaves has a potential to restore the suppressed reproduction associated with lead exposure and prevented lead‐induced testicular toxicity in male Wistar rats.     

Isoflavones and their effects on the onset of puberty in male Wistar rats

This study was performed to determine how two of the most important isoflavones, genistein and daidzein, affect the gonadal axis in male prepuberal rats. One hundred and seventy‐five prepuberal male Wistar rats were allocated into seven groups: one control group and six experimental groups that were orally administered a high or low dose of genistein, daidzein or a mixture of both. Testosterone determination was assayed by EIA. The testes and body weights were measured, and the histology of the epididymis with the sperm content and epididymal sperm count were evaluated. In the control group, we observed an increase in the serum testosterone levels (>2.5 ng ml^?1) at the third week (52 days), which corresponded to the onset of puberty in these rats. The same increase in serum testosterone levels was observed at the fourth week in rats that received low doses of isoflavones; therefore, we concluded that the onset of puberty was delayed. At high doses, there was no significant increase in testosterone levels, which could be related to the fact that these male rats did not reach puberty. These findings were supported by the results obtained from the analysis of the epididymal content as well as the testes/body weight ratio.     

Effect of two different extracts of red maca in male rats with testosterone-induced prostatic hyperplasia

Aim： To determine the effect of two different extracts of red maca in male rats. Methods： Prostatic hyperplasia was induced in male rats with testosterone enanthate （TE）. The study comprised six groups： one control group （group 1）, one group treated with TE （group 2）, two groups treated with TE and aqueous extract of red maca （groups 3 and 4）, one group treated with hydroalcoholic extract of red maca （group 5） and one group treated with finasteride （0.1 mg, group 6）. Differences in the aqueous extract dependent on the length of time of boiling, whether for 2 or 3 hours, for groups 3 and 4 was assessed. Extracts of red maca contained 0.1 mg of benzylglucosinolate. Thereafter, a doseresponse effect of different doses of benzylglucosinolates （0.02-0.08 mg） in red maca extracts was assessed. Results： Prostate weight was similar in rats treated with freeze-dried aqueous extract of red maca prepared after 2 and 3 hours of boiling. Freeze-dried aqueous extract of red maca, hydroalcoholic extract of red maca and finasteride reduced prostate weight in rats with prostatic hyperplasia. No difference was observed between the data obtained from aqueous extract or hydroalcoholic extract of red maca. A dose dependent reduction of prostate weight was observed with the increase of the dose of benzylglucosinolates in red maca extracts. Conclusion： The present study showed that hydroalcoholic or aqueous extract of red maca containing 0.1 mg of benzylglucosinolate can reduce prostate size in male rats in which prostatic hyperplasia had been induced by TE.     

Protective effects of Artocarpus altilis (Moraceae) on cadmium‐induced changes in sperm characteristics and testicular oxidative damage in rats

Cadmium (Cd) is a major environmental toxicant and an endocrine disruptor. We investigated the protective effects of methanol extract of Artocarpus altilis (AA) against Cd‐induced testicular damage in rats while quercetin (Que) served as standard. The total flavonoids and phenolic contents (TFC and TPC), 2, 2‐diphenyl‐1‐picrylhydrazyl (DPPH) and hydroxyl (OH) radicals scavenging activities of AA were determined. In vivo, thirty male Wistar rats were assigned to six groups and orally treated with corn oil (control), Cd alone, Cd+Que, Cd+AA, Que and AA alone. Que and AA were given at doses of 25 and 200 mg kg^?1, respectively, for 3 weeks and challenged with two doses of Cd (1.5 mg kg^?1). Results showed that TFC and TPC of AA increased with increase in concentration. AA scavenged DPPH and OH radicals in a dose‐dependent manner. Administration of Cd significantly increased the relative weight of testis of rats. Lipid peroxidation was significantly increased while antioxidant parameters decreased in testis of Cd‐treated rats. Also, Cd‐treated rats had significantly reduced sperm count, motility, sialic acid, luteinising hormone and testosterone relative to controls. Pre‐treatment with AA or Que significantly attenuated the biochemical alterations observed in Cd‐treated rats. Overall, AA protects against Cd‐induced testicular damage via antioxidative mechanism.     

Protective effect of Zingiber officinale extract on rat testis after cyclophosphamide treatment

Decreasing the side effects of chemotherapy in testis has been the subjects of many studies. In this study, the protective effects of Zingiber officinale extract on rat testis were investigated after chemotherapy with cyclophosphamide. Histological and biochemical parameters were compared in cyclophosphamide‐treated rats with or without ginger extract intake. Wistar male rats were randomly divided into four groups each 10. The control group received a single injection of 1 ml isotonic saline intraperitoneally. The Cyclophosphamide (CP) group received a single dose of cyclophosphamide (100 mg kg^?1 BW) intraperitoneally. CP + 300 and CP + 600 groups received orally 300 or 600 mg of ginger extract, respectively, for a period of 6 weeks after cyclophosphamide injection. The morphologic and histological structure of the testis was compared in different groups of the rats. Also, factors like malondialdehyde, reactive oxygen species, total antioxidant capacity and testosterone level were assessed in blood serum as well. Our results showed that although ginger extract could not change testis weight, malondialdehyde (MDA) and ROS, but antioxidant and testosterone levels in serum were increased significantly. Also, an obvious improved histological change was seen in CP + 300 and CP + 600 groups in comparison with CP group. These protective effects of ginger on rat testis after cyclophosphamide treatment could be attributed to the higher serum level of antioxidants.     

Recovery of lead‐induced suppressed reproduction in male rats by testosterone

The objective of the present study was to investigate the effects of testosterone in recuperation of lead‐induced suppressed reproduction in adult male rats. Lead acetate was administered orally to adult male rats (95 ± 5 days) at dosage level of 0.05 and 0.15% for 55 days through drinking water and injected intraperitoneally with either testoviron depot at a dose of 4.16 mg kg^?1 body weight or vehicle alone on days 1, 7 and 14 respectively. At the end of treatment, control and treated males were cohabited with untreated normal‐cycling females. After cohabitation for 5 days, all the male rats were killed and weights of reproductive organs were determined. Significant increase in the indices of testis, epididymis, seminal vesicles, vas deferens and prostate glands was observed in testosterone (T)‐treated rats when compared to those of lead‐exposed rats. Testosterone treatment significantly increased epididymal sperm count, motile spermatozoa, viable spermatozoa and HOS tail‐coiled spermatozoa and also the activity levels of testicular 3β‐ and 17β‐hydroxysteroid dehydrogenases when compared to those of lead‐exposed males. From the results, it can be hypothesised that supplementation of testosterone mitigated lead‐induced suppressed reproduction in male rats.     

Effect of red maca (Lepidium meyenii) on prostate zinc levels in rats with testosterone-induced prostatic hyperplasia

Lepidium meyenii (maca) is a plant that grows exclusively above 4000 m in the Peruvian central Andes. Red maca (RM) extract significantly reduced prostate size in rats with benign prostatic hyperplasia (BPH) induced by testosterone enanthate (TE). Zinc is an important regulator of prostate function. This study aimed to determine the effect of RM on prostate zinc levels in rats with BPH induced by TE. Also, the study attempted to determine the best marker for the effect of RM on sex accessory glands. Rats treated with RM extract from day 1 to day 14 reversed the effect of TE administration on prostate weight and zinc levels. However, RM administered from day 7 to day 14 did not reduce the effect of TE on all studied variables. Finasteride (FN) reduced prostate, seminal vesicle and preputial gland weights in rats treated with TE. Although RM and FN reduced prostate zinc levels, the greatest effect was observed in TE-treated rats with RM from day 1 to day 14. In addition, prostate weight and zinc levels showed the higher diagnosis values than preputial and seminal vesicle weights. In conclusion, RM administered from day 1 to day 14 reduced prostate size and zinc levels in rats where prostatic hyperplasia was induced with TE. Also, this experimental model could be used as accurately assay to determine the effect of maca obtained under different conditions and/or the effect of different products based on maca.     

Effects of Melandrium firmum methanolic extract on testosterone-induced benign prostatic hyperplasia in Wistar rats

Benign prostatic hyperplasia (BPH) is an age-related disease of unknown aetiology characterized by prostatic enlargement coincident with distinct alterations in tissue histomorphology. Instead of therapeutic agents that can cause severe side effects, plant extracts are frequently used to treat BPH. In this study, we investigated whether the Melandrium firmum methanolic extract (MFME) improves BPH, using the testosterone propionate (TP)-induced BPH rat model. Castration was performed via the scrotal route under sodium pentobarbital anaesthesia. BPH in castrated rats was generated via daily subcutaneous injections of TP (3 mg kg(-1)) dissolved in corn oil, for 4 weeks. MFME was administered daily by oral gavage at a dose of 200 mg kg(-1) for 4 weeks, along with the TP injections. The control group received injections of corn oil subcutaneously. At the scheduled termination of the experiment, all rats were killed and their prostates weighed; the relative prostate weight (prostate/body weight ratio) was calculated, and histomorphological changes in the prostate were examined. Additionally, we measured the levels of testosterone and dihydrotestosterone (DHT) in the serum and the prostate. Experimentally induced BPH led to marked decreases in the relative prostate weight and the DHT levels in the serum and the prostate. Histologically, BPH was evident in the ventral lobe of the prostate, and MFME treatment suppressed the severity of the lesions. These results indicate that MFME effectively inhibits the development of BPH induced by testosterone in a rat model. Further studies will be needed to identify the compound(s) responsibility for inducing the protective effect against BPH and determine its mechanism of action.     

红三叶异黄酮对大鼠前列腺增生的抑制作用

目的 观察红三叶异黄酮对雌/雄激素协同作用诱导的大鼠前列腺增生的影响.方法 应用雌/雄激素协同作用诱导大鼠前列腺增生方法建立前列腺增生模型,设立阴性对照组、增生模型组、保列治阳性对照组及红三叶异黄酮实验组.饲养28 d后称取各组大鼠前列腺的湿重、计算前列腺指数;HPIAS-1000图形图像分析系统观察各组大鼠前列腺组织形态学改变.结果 (1)红三叶异黄酮组大鼠前列腺湿重(780.31±47.10)及前列腺指数(1.79±0.12)显著低于模型组(1371.10±99.60;2.04±0.13)(P<0.01),但前列腺湿重(780.31±47.10)与保列治对照组(780.50±33.99)差异无统计学意义(P>0.05);(2)形态学结果显示红三叶异黄酮组大鼠增生前列腺组织受到抑制.结论 红三叶异黄酮能显著抑制大鼠的前列腺增生.     

Pharmacological effects of the lipidosterolic extract of Serenoa repens (Permixon) on rat prostate hyperplasia induced by hyperprolactinemia: comparison with finasteride

BACKGROUND: The growth of the prostate gland is mainly dependent on androgens. Other hormones, like prolactin (PRL), also influence prostate development. Our purpose was to analyze and compare the effects of two drugs (5alpha-reductase inhibitor) used in the therapy of benign prostatic hyperplasia: lipidosterolic extract of Serenoa repens (LSESR), and finasteride in an in vivo model of rat prostate hyperplasia induced by hyperprolactinemia. METHODS: Hyperprolactinemia was induced by 30 daily injections of sulpiride. Wistar rats received daily gavages of LSESR or finasteride. We used the following groups: control, castrated, castrated with a substitute testosterone (T), or 5alpha-dihydrotestosterone (DHT) implant. RESULTS: Hyperprolactinemia increases the wet weight and induces hyperplasia in the lateral prostate (LP). Unlike finasteride, LSESR significantly reduced LP growth and hyperplasia in castrated, DHT-implanted, and sulpiride-treated rats. CONCLUSIONS: Finasteride was only capable of inhibiting the effect of androgens on rat prostate enlargement. LSESR inhibited not only the androgenic but also the trophic effect of PRL in rat LP hyperplasia.     

Effect of androgen deprivation on the expression of aquaporins in rat prostate and seminal vesicles

The aim of this study was to investigate the level of secretions of prostate and seminal vesicles and its association with the expression of AQP0, 1, 4, 5, 6 and 8 in castrated rats. Eight‐week‐old male Sprague‐Dawley (SD) rats (n = 18) were randomly divided into control group, castrated rats group and castrated followed testosterone replacement group. Four weeks after surgery, the secretions and expression of AQP0, 1, 4, 5, 6 and 8 of prostate and seminal vesicles were determined. Serum testosterone was significantly lower in castrated groups than in control and testosterone replacement groups (P < 0.05). The level of prostate and seminal vesicle secretions and the expressions of AQP0, 1, 4, 5, 6 and 8 in prostate and seminal vesicles were significantly lower in castrated group than in control and castrated followed testosterone replacement groups (P < 0.05). The decreased prostatic and seminal vesicle secretions in castrated rats may be related to the decrease in AQP0, 1, 4, 5, 6 and 8 in prostatic tissue and seminal vesicles.     

Antiandrogenic activities of Glycyrrhiza glabra in male rats

Abnormal levels of androgens cause many diseases like benign prostatic hyperplasia and hormone dependent cancers. Although the reduction in serum testosterone (T) by Glycyrrhiza glabra has been reported, its effects on seminal vesicle (SV) and prostate tissues have never been reported. This study was carried out to investigate different aspects of antiandrogenic properties of this plant. Immature male rats were divided into five groups ( n  = 7): castrated rats without any treatment received only vehicle; castrated rats plus T replacement; three castrated groups with T replacement plus various doses of G. glabra extract (75, 150 and 300 mg/kg). All of the injections were carried out once daily in subcutaneous manner for 7 days. On the eighth day, blood samples were collected for total T measurement. Ventral prostate (VP), SV and levator ani muscle were dissected and weighed. Slides prepared from prostate were assessed histologically. The variation in the relative and absolute volume of the prostate tissue compartments was determined. Those receiving the doses of 150 and 300 mg/kg showed a significant reduction ( p  <   0.05) in prostate weight, total T and VP epithelium/stroma ratio (V/V). These results in SV and levator ani were shown in response to 300 mg/kg of extract. Increasing in T metabolism, down-regulation of androgen receptors or activation of oestrogen receptors could be involved mechanisms. This study showed that alcoholic extract of G. glabra has antiandrogenic properties.     

Gallic acid protects against cyclophosphamide‐induced toxicity in testis and epididymis of rats

The protective role of gallic acid (GA) on reproductive toxicity induced by cyclophosphamide (CPA), an antineoplastic drug, was investigated in male Wistar rats. Sixty rats were grouped into 10 rats per group. Group 1 (control) received distilled water. Rats in groups 2 and 3 received GA alone at 60 and 120 mg kg^?1 for 14 consecutive days, respectively. Group 4 received a single intraperitoneal dose of CPA at 200 mg kg^?1 on day 1. Groups 5 and 6 received a single dose of CPA (200 mg kg^?1) intraperitoneally on day 1 followed by treatment with GA at 60 and 120 mg kg^?1 for 14 consecutive days, respectively. In testes and epididymis of the treated rats, CPA administration resulted in significant elevation (P < 0.05) in malondialdehyde (MDA), nitrite and hydrogen peroxide levels. There was a significant decrease in the activities of superoxide dismutase and glutathione‐S‐transferase. Furthermore, there were significant reductions in plasma luteinising hormone (LH), follicle stimulation hormone (FSH) and testosterone levels, which were accompanied by significant decrease in sperm motility and viability in CPA‐treated rats. Histological examination revealed marked testicular and epididymal atrophy in CPA alone treated rats and these aberrations were reversed by GA. In conclusion, GA has capacity to protect against reproductive toxicity induced by cyclophosphamide.     

Effect of etodolac hydrazone,a new compound synthesised from etodolac,on spermatozoon quality,testicular lipid peroxidation,apoptosis and spermatozoon DNA integrity

The aim of this study was to investigate the effect of etodolac hydrazone (EH), a new compound synthesised from etodolac, on spermatozoon quality, testicular lipid peroxidation, apoptosis and spermatozoon DNA integrity in rats. Group 1 (n = 8) received 1 ml dimethyl sulfoxide (DMSO) daily (Control); group 2 (n = 8) was treated with 5 mg kg^?1 day^?1 EH, dissolved in 1 ml DMSO (EH‐5); and group 3 (n = 8) was treated with 10 mg kg^?1 day^?1 EH, dissolved in 1 ml DMSO (EH‐10). All administrations were performed by gavage and maintained for 8 weeks. Both doses of EH administration caused significant decreases in absolute and relative weights of testis, whole epididymis, right cauda epididymis, and spermatozoon motility, spermatozoon count in comparison with the control group. Only 10 mg kg^?1 day^?1 EH administration caused significant decreases in absolute and relative weights of seminal vesicles and serum testosterone level, and significant increases in testicular lipid peroxidation level, and numbers of TUNEL+ apoptotic germ cells and spermatozoa with damaged DNA along with some histopathological damages when compared to the control group. However, body and ventral prostate weight, and testicular antioxidant markers (glutathione, glutathione‐peroxidase and catalase), were unaffected significantly by both doses of EH administration. In conclusion, two different doses of EH, in particular its high dose, damage to testicular spermatogenic cells and spermatozoon DNA and, it decreases spermatozoon motility, count and testosterone level in healthy rats.     

A selective alpha1A-adrenoceptor antagonist inhibits detrusor overactivity in a rat model of benign prostatic hyperplasia

PURPOSE: Alpha(1)-adrenoceptor antagonists relax the obstructed prostatic urethra and suppress the irritative symptoms frequently observed in patients with benign prostatic hyperplasia. We investigated the effects of 3 alpha(1)-adrenoceptor antagonists on urodynamics in rats with hormone induced benign prostatic hyperplasia to determine which alpha(1)-adrenoceptor subtype selective antagonists would suppress irritative symptoms. MATERIALS AND METHODS: Rats were treated with testosterone and 17beta-estradiol by weekly intramuscular injections. After 4 weeks a pressure flow study was done and the effects of the alpha(1)-adrenoceptor antagonists KMD-3213 silodosin, tamsulosin and prazosin on urodynamics were compared. We especially investigated the involvement of the bladder and prostatic urethra to clarify the mechanism of detrusor overactivity expression. RESULTS: Hormone treatment induced benign prostatic hyperplasia and resulted in detrusor overactivity, as determined by cystometry. Baseline perfusion urethral pressure and the phenylephrine induced increase in it were significantly higher in rats with vs without benign prostatic hyperplasia. Cystometry in hormone treated female rats did not show detrusor overactivity. KMD-3213 decreased detrusor overactivity, similar to other alpha(1)-adrenoceptor antagonists. CONCLUSIONS: These results suggest that an excessive response to sympathetic nerve stimulation, which is mainly mediated via alpha(1A)-adrenoceptor, in the hypertrophied prostate gives rise to detrusor overactivity. Furthermore, the alpha(1A)-adrenoceptor selective antagonist KMD-3213 would be suitable for improving irritative symptoms in patients with benign prostatic hyperplasia.