Genotype distribution of T cell receptor β gene in Indonesian nasopharyngeal carcinoma patients.

Background: Nasopharyngeal carcinoma (NPC) is a multifactorial genetic disease, characteristically endemic and shows considerable differences in its geographical distribution. Besides infection with EBV, genetic factors such as polymorphisms of TCR-β gene contribute to the incidence of NPC. This study investigates the association of TCR-β gene polymorphisms with individual susceptibility to develop NPC in Indonesian ethnic groups. Methods: The study was carried out by the PCR-RFLP method using Bgl II restriction enzyme to digest TCR-β gene. The PCR-RFLP analysis of TCR-β gene was used to determine allotypes of TCR-β gene in NPC patients and control among ethnic Chinese and indigenous groups in the population of Indonesia. Results: The results indicate that the distribution of TCR-β gene allotypes between NPC patients and controls are not significantly different (p > 0.05); however, the frequency of A allele tends to increase in NPC patients. The distribution of TCR-β gene allotypes between Chinese ethnic group was not signifi cantly different from indigenous groups (p > 0.05). Conclusion: The distribution of TCR-β gene allele between NPC group and control groups showed no difference. The distribution of TCR-β gene between ethnic Chinese and indigenous groups showed no difference. Polymorphisms of TCR-β gene are not associated with NPC and ethnic groups in Indonesian population.

Polyclonal VDAC3 antibody decreases human sperm motility: a novel approach to male contraception.

Background: Voltage dependent anion channels (VDAC) mediate transport of anions, cations and ATP which play an important role in sperm motility. This study was aimed to examine the effect of polyclonal VDAC3 antiserum to human sperm motility. Methods: Polyclonal VDAC3 antiserum used in this study was produced in rabbits by immunization of VDAC3-specific synthetic peptides. Preimmunserum was collected before immunization and used for control experiment. Recognition of VDAC3 antiserum to antigen in human sperm was performed by western blot. Thirty sperm samples obtained from fertile men which had high quality of sperm motility were washed and collected by Percoll gradient. Sperm motility was assessed by means of evaluation of sperm velocity (seconds per 0.1 mm distance) and the number of unmoved sperm (million per ml) which were observed 0 minute, 30 minutes and 60 minutes after addition of VDAC3 antiserum and preimmunserum as a control. Both data were analyzed by SPSS 13.0 software. Results: VDAC3 antiserum recognized VDAC3 protein in human sperm. Statistical analysis demonstrated that there were increasing numbers of unmoved spermatozoa after addition of anti-VDAC3 antiserum in vitro for 60 minutes observation compared with preimmunserum (control). We found also that sperm velocity decreased signifi cantly after giving anti-VDAC3 antiserum in vitro for 0 minute, 30 minutes, and 60 minutes compared with pre-immunee serum (control). Conclusion: VDAC3 antiserum can decrease motility of human sperm. and may provide a novel principle of male contraception in the future.

Testosterone undecanoate and depo medroxyprogesterone acetate induced azoospermia through increased expression of spermatogenic cell caspase 3.

The administration of a combination of testosterone undecanoate (TU, a long-acting androgen) and depo-medroxyprogesterone acetate (DMPA) were investigated in term of suppression of rat sperm concentration in vivo to azoospermia through increasing activity of spermatogenic cell caspase 3. Adult Sprague Dawley rats received TU and DMPA of 2.5 mg and 1.25 mg, respectively, a regimen known to rapidly reduce intra testicular testosterone and to produce azoospermia within 12 weeks. Caspase 3 positive sperm cells increased compared with control levels during 6 weeks post-injection and increased further through 60 weeks. Immunohistochemistry for caspase 3 revealed that spermatocytes represented the predominant caspase 3 positive germ cells. Modest immunoreactivity for caspase-3 was localized to nuclear region of the germ cells of control and treated testes. Immunohistochemistry study revealed significantly increased caspase-3 expression in nuclei of germ cells during administration of TU+DMPA to rats. Additionally, the caspase 3 content was significantly increased in germ cells during rats were administered TU+DMPA (453.90±84.88 cells/200 seminiferous tubules) and caspase 3 significant increase in immunoreactivity was localized to the nuclei of spermatogonia, spermatocytes, and spermatids. Taken together, these results indicated that azoospermia due to reduced intratesticular testosterone concentration was caspase-3 activation dependent and suggested that the increase in active caspase-3 in the nucleus may be involved in the induction of decreased sperm production.

The association of CAG repeat length polymorphisms of androgen receptor gene and spermatogenesis impairment in several Indonesian men.

Spermatogenesis impairment is the main cause of infertility in men. Androgen is believed to play a critical role in regulating spermatogenesis. Androgen acts by binding to the androgen receptor (AR) which is a protein regulator of DNA transcription. Exon 1 of AR gene contains a CAG repeat length polymorphism and it is believed to interfere AR function. This study includes DNA isolation from peripheral blood and amplification of CAG repeat fragments by PCR method. CAG repeat lengths were determined by electrophoresis on 6% denaturing gel polyacrylamide. We found that the mean CAG repeat lengths were 24,3 ± 3,4 in oligozoospermic/azoospermic men and 22,7 ± 2,7 in normozoospermic men. The difference in CAG repeat length between the two groups was statistically significant (p = 0,031, t-test). Nevertheless, there was no correlation between CAG repeat lengths and sperms concentration (rs = -0,038; p = 0,775). This result suggest that the expansion of CAG repeat length was not the main cause of spermatogenesis impairment.

Single nucleotide polymorphisms of follicle-stimulating hormone receptor promoter and their impacts to the promoter activities.

Women of reproductive ages are varies in their responses to exogenous FSH stimulations. The difference of FSHR genotype due to the polymorphisms in exon 10 is one of its significant factors. To know further whether the core promoter of FSHR is also polymorphic and to know whether those polymorphisms influence the promoter activity, we did polymorphism screening of FSHR promoter to 262 women undergoing IVF/ICSI, followed by functional study to know the impact of polymorphisms to the promoter activity. This study indicated that the core promoter of human FSHR is polymorphic. We found five SNPs at positions –29, –37, –114, –123 and –138 in addition to the variety number of adenines. Polymorphism at position –123 significantly decreased the promoter activity, in contrast, polymorphism at position –37 and –138 significantly increased the promoter activity, whereas polymorphism at position –29, –114 and short adenines stretch did not significantly influence the promoter activity. The differences of the promoter activities due to polymorphisms might change the ovarian sensitivity to FSH.