Restricted Expression of the Human DAZ Protein in Premeiotic Germ Cells William J. Huang1,2, Yi-Wen Lin3,4, Kuang-Nan Hsiao3, Karyn S. Eilber5,9, Eduardo C. Salido6,7 and Pauline H. Yen3,4,8,10
1 Department of Urology, School of Medicine; National Yang-Ming University, Taipei 11221, Taiwan
2 Division of Urology, Department of Surgery, Taipei Veterans General Hospital Taipei 11217, Taiwan
3 Institute of Biomedical Sciences, Academia Sinica, 128 Academia Road, Section 2, Taipei 11529, Taiwan
4 Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 11490, Taiwan
5 Division of Urology, Department of Surgery, Harbor-UCLA Medical Center, Torrance, CA 90505, USA
6 CIBERER, Hospital Universitario de Canaries Spain;
7 Department of Pathology, Universidad de La Laguna, E-38071 Tenerife, Spain
8 Division of Medical Genetics, Harbor-UCLA Medical Center, Torrance, CA 90505, USA
9 Present address: Century Urology Medical Group, 2080 Century Park East, Suite 1407, Los Angeles, CA 90067, USA
BACKGROUND: The role of the Y-chromosome encoded Deleted in Azoospermia (DAZ) gene family in spermatogenesis remains unclear. The ability of men without the DAZ gene to produce sperm as well as the lack of selective pressure on DAZ exon sequences during evolution cast doubts on its functional significance. Most men have four DAZ genes encoding protein isoforms that differ significantly in size. However, the published Western blots showed only a single “DAZ” band, raising the possibility that not all four DAZ genes are expressed. METHODS: RT-PCR, Western blotting, and immunostaining were used to study the expression of the 4 DAZ genes and the autosomal DAZL gene in human testes and in tissue culture cells.
RESULTS: RNA transcripts of all 4 DAZ genes were found in the testis, but at much lower levels than that of the DAZL transcripts. Expression in cultured somatic cells showed that DAZ transcripts encoding multiple DAZ repeats were translated inefficiently. No DAZ proteins could be unambiguously identified on Western blots when the testicular samples from three patients without the DAZ genes were used as negative controls. Nonetheless, low levels of DAZ were detected in the cytoplasm of spermatogonia by immunostaining.
CONCLUSION: The expression of the DAZ proteins is restricted to the spermatogonia in adult human testes and suggests a premeiotic role for the DAZ proteins.
男性學論文獎基礎組
2007 BJU International 100, 1116-1120
The Associations among eNOS G894T Gene Polymorphism, Erectile Dysfunction and Related Risk Factors
1 Department of Urology, Kaohsiung Medical University Hospital,
2 Department of Urology, Kaohsiung Municipal Hsiao-Kang Hospital,
3 Department of Microbiology, Kaohsiung Medical University, Kaohsiung, Taiwan
Objective: To investigate the possible correlations among eNOS G894T polymorphisms, erectile dysfunction and related risk factors in the Taiwanese population.
Materials and Methods: Included in our study were 151 patients with erectile dysfunction (ED) and 77 healthy controls. All subjects had complete collections of clinical histories and laboratory data about ED. International index of erectile function 5 (IIEF-5) was used to assess their erectile conditions. The eNOS G894T polymorphisms were determined using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.
Results: A total of 228 subjects were enrolled in our study with a mean age of 58.6±9.7 years. In a univariate analysis, our data showed that age, serum testosterone level and the prevalence of diabetes mellitus (DM) and hypertension were significantly different between ED patients and healthy controls (p<0.01). In multiple logistic regression analysis, the results showed that DM, age and hypogonadism were three independent risk factors for ED (p=0.018, p=0.046 and p=0.016, respectively). The prevalence of ED in T allele carriers (GT/TT) was significantly higher than G allele carriers (GG) (80.0% vs 63.3%, p=0.04). Also the eNOS 894T allele carriers had significantly lower IIEF-5 score than eNOS 894G allele carriers (13.2±5.3 vs 15.7±6.1, p=0.01) and it was associated with increment of T allele number (11.0±5.6 vs 13.6±5.2 vs 15.7±6.1, p=0.03).
Conclusion: Our results indicated that DM, age and hypoganadism are the three significant independent risk factors for ED. Also, in the Taiwanese population, the eNOS 894T allele carriers are at a higher risk for ED in prevalence and severity and this may be a factor of genetic susceptibility.
輝瑞論文獎臨床組
Adult Urology, p 677-680
Relationship between Serum Testosteroneand Measures of Benign Prostatic Hyperplasia in Aging Males
1 Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan;
2 Department of Urology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
Objectives: Previous studies of the associations of serum testosterone levels and measures of benign prostatic hyperplasia (BPH) have not been consistently reported and have focused on a predominately white population. This study was conducted to evaluate the relationships between serum testosterone levels and measures of BPH in the aging male population of Taiwan.
Methods: A free health screening for aging men (≥ 45 years old) was conducted in Kaohsiung Medical University Hospital in August 2004. Clinical conditions of BPH were assessed by digital rectal examination, serum PSA level, International Prostate Symptom Score (IPSS) and transrectal ultrasonography. Serum testosterone levels (total-, free-, bioavailable-) were also evaluated. Subjects also completed a health and demographics questionnaire, and received a detailed physical examination.
Results: The final study population consisted of 148 patients with a mean age of 59.8 years. Age was positively correlated with prostate volume (r=0.309, P<0.001), IPSS (r=0.162, P=0.029) and the level of serum PSA (r=0.382, P<0.001). Serum testosterone levels (total-, free-, bioavailable-) were not significantly correlated with prostate volume and IPSS. In the multivariable linear regression analysis, only age was still significantly correlated with prostate volume (P<0.001).
Conclusions: In our study, serum testosterone levels in aging males were not correlated with the measures of BPH, including prostate volume and IPSS, whether total testosterone, free testosterone or bioavailable testosterone was used. Age was correlated with the measures of BPH, especially with prostate volume. Further large studies may be needed to confirm these preliminary results.
男性學論文獎
