Dutasteride-mediated morphological changes in the genitourinary tract associated with altered expression patterns of the androgen and estrogen receptors in male rats.

We evaluated the effects of dutasteride on the genitourinary tract using fifteen 8-week-old male Sprague-Dawley rats. Animals were divided into three groups comprising five animals each and treated as follows. Group A was a control group, members of Group B received oral administration of dutasteride 0.1 mg/kg/day from the age of 8 to 16 weeks, and members of Group C were castrated at the age of 8 weeks. All rats were killed at the age of 16 weeks for the sample collection of blood, bladder, prostate, seminal vesicles, and penis. Then, we evaluated the pathological examination for evaluating the tissue fibrosis and hormonal receptor expression. The results showed that the mean size of the prostate and seminal vesicles was smaller in Group B and Group C than in Group A. Serum and tissue concentrations of both testosterone and dihydrotestosterone were remarkably reduced in serum and all tissues in Group C compared with Group A. On the other hand, in Group B, only dihydrotestosterone was reduced in serum and penis. Histopathological examination revealed that Group C showed statistically significant histological changes, such as an increase in fibrotic tissue in the bladder, prostate, and penis. Similarly, Group B showed fibrotic changes in the prostate and penis compared with the Group A. Immunofluorescent staining revealed that the androgen receptor was more strongly expressed than the estrogen receptor beta in Group A. On the other hand, in Group C, weak expression of the androgen receptor and strong expression of the estrogen receptor beta was noted. In Group B, these changes were noted in the prostate and penis. These findings suggest that dutasteride cause morphological changes not only in prostate but also in penis. These changes are associated with altered expression patterns of androgen receptor and estrogen receptor.

Effects of dutasteride on serum free-testosterone and clinical significance of testosterone changes.

Sixty-two patients with benign prostate hyperplasia (BPH) who were being treated with dutasteride participated in this study. Prostate volume, uroflowmetry, blood tests, the International Prostate Symptom Score (IPSS) and International Index of Erectile Function (IIEF-5) were determined before and 1, 3 and 12 months after the treatment with dutasteride. Patients were divided into two groups based on changes in serum testosterone after 1 month: Group A (>20% increase; n = 33) or Group B (<20% increase; n = 29). Serum free-testosterone levels were 20.4% higher after 1 month and remained constant thereafter. When Groups A and B were compared, baseline free-testosterone levels were significantly lower in Group A, IPSS QOL was significantly better in Group A at 3 and 12 months, and no significant differences were observed in uroflowmetry, prostate volume, IPSS or IIEF-5. A univariate analysis identified serum free-testosterone levels and the IPSS storage symptom subscore as significant factors influencing IPSS QOL at 12 months, and only the IPSS storage symptom subscore appeared to be independently related to IPSS QOL. These results indicate that dutasteride increases serum free-testosterone levels in BPH patients, particularly with low baseline free-testosterone levels, and the increase in free-testosterone may have further add-on impacts on their urinary tract symptoms.

Seminal level of clusterin in infertile men as a significant biomarker reflecting spermatogenesis.

The objective of this study was to assess the impact of seminal clusterin level on spermatogenesis in infertile men. This study included 89 men who visited our clinic due to infertility, consisting of 28, 33, and 28 diagnosed with normospermia, oligozoospermia and nonobstructive azoospermia (NOA) respectively. The seminal clusterin concentrations measured by enzyme-linked immunosorbent assay were 47.9, 28.2 and 18.4 ng ml-1 in men with normospermia, oligozoospermia and NOA, respectively, with significant differences among these three groups (P < 0.01). Microdissection testicular sperm extraction (MD-TESE) was performed in the 28 men with NOA, and spermatozoon was successfully retrieved from 9. There was a significant correlation between seminal clusterin level and testicular clusterin protein expression evaluated by immunohistochemical staining in these men with NOA (P = 0.026). Of several parameters available before MD-TESE, the univariate analysis identified serum follicle-stimulating hormone (FSH) level <10 IU ml-1 and seminal clusterin level ≥18 ng ml-1 as significant predictors of sperm retrieval, and of these, only serum FSH level <10 IU ml-1 was shown to be independently associated with sperm retrieval in the multivariate analysis. Accordingly, it might be worthy to further evaluate the significance of seminal clusterin level as a biomarker for the assessment of spermatogenic status in infertile men.

Prospective assessment of health-related quality of life in men with late-onset hypogonadism who received testosterone replacement therapy.

The objective of this study was to characterise the status of health-related quality of life (HRQOL) in Japanese men with late-onset hypogonadism (LOH) treated with testosterone replacement therapy (TRT). HRQOL in 69 consecutive Japanese men with LOH undergoing TRT for at least 6 months was prospectively evaluated before and 6 months after the initiation of TRT using the Medical Outcomes Study 8-Item Short-Form Health Survey (SF-8). All eight-scale scores except for bodily pain (BP) in the 69 patients at 6 months after the introduction of TRT significantly improved compared with those before TRT; however, all scale scores except for BP in the 69 patients were significantly inferior to those in age-matched Japanese controls irrespective of the timing of SF-8. Multivariate analyses of several parameters revealed that both age and Aging Male Symptom (AMS) score had an independent impact on mental health (MH), despite the lack of an independent association between any score and the remaining factors examined. TRT appeared to significantly improve the status of HRQOL in men with LOH; however, even after the introduction of TRT, HRQOL associated with MH remained significantly impaired in elderly men and/or those with a high AMS score.