POSTOPERATIVE CHANGES OF SPERM CHROMATIN HETEROGENEITY, USING ACRIDINE ORANGE STAINING, IN VARICOCELE PATIENTS

The effect of varicocele on sperm morphology and DNA maturity: does acridine orange staining facilitate diagnosis?

OBJECTIVE

The aim of this study was to determine whether Acridine Orange (AO) can be used as a routine procedure in a physician's office to detect sperm deoxyribonucleic acid (DNA) fragmentation in patients with varicoceles.

MATERIAL AND METHODS

Forty-five patients with a mean age of 30.4 years, who had been diagnosed with varicoceles by physical examination and 30 healthy males with a mean age of 28.3 years and without any signs of varicoceles were included in this study. Doppler Ultrasonography was performed to each individual in addition to physical examination. Semen analyses were performed by the same biologist. Sperm morphology was evaluated according to the World Health Organization (WHO) criteria and Kruger's strict criteria. After routine semen analysis, the samples were fixed separately for further examination with AO staining.

RESULTS

In routine semen analyses, total sperm count, total motile sperm count, and fast direct forward motile and direct forward motile sperm counts were significantly lower in patients with varicoceles, and the immotile sperm count was significantly higher in patients with varicoceles compared to the control group. Kruger's examination revealed a lower sperm count with normal morphology in patients with varicoceles. After AO staining, the ratio of spermatozoa demonstrating red and green coloration were 6.5±11.0% and 93.5±11.0%, respectively in the varicocele group and 1.0±1.0% and 99.0±1.0%, respectively in the control group (p<0.001).

CONCLUSION

Semen analysis using AO staining can be performed under a clinician's office conditions with a fluorescent microscope without any additional equipment. Further studies are needed to validate the AO staining with more extensively used and well-known methods. Therefore, AO staining can be used as a simple and reliable method that can be performed daily in a physician's office in infertility and andrology clinics.

mir-34b/c and mir-449a/b/c are required for spermatogenesis, but not for the first cleavage division in mice

Mammalian sperm are carriers of not only the paternal genome, but also the paternal epigenome in the forms of DNA methylation, retained histones and noncoding RNAs. Although paternal DNA methylation and histone retention sites have been correlated with protein-coding genes that are critical for preimplantation embryonic development, physiological evidence of an essential role of these epigenetic marks in fertilization and early development remains lacking. Two miRNA clusters consisting of five miRNAs (miR-34b/c and miR-449a/b/c) are present in sperm, but absent in oocytes, and miR-34c has been reported to be essential for the first cleavage division in vitro. Here, we show that both miR-34b/c- and miR-449-null male mice displayed normal fertility, and that intracytoplasmic injection of either miR-34b/c- or miR-449-null sperm led to normal fertilization, normal preimplantation development and normal birth rate. However, miR-34b/c and miR-449 double knockout (miR-dKO) males were infertile due to severe spermatogenic disruptions and oligo-astheno-teratozoospermia. Injection of miR-dKO sperm into wild-type oocytes led to a block at the two-pronucleus to zygote transition, whereas normal preimplantation development and healthy pups were obtained through injection of miR-dKO round spermatids. Our data demonstrate that miR-34b/c and miR-449a/b/c are essential for normal spermatogenesis and male fertility, but their presence in sperm is dispensable for fertilization and preimplantation development.

Analysis of inter-examination differences in sperm nuclear vacuoles among male patients with infertility

We analyzed the inter-examination differences in sperm nuclear vacuoles among male patients with infertility. We enrolled 56 male patients with infertility who underwent multiple semen analyses and high-magnification observation of the sperm head. A total of 162 ejaculates were evaluated. The average patient age was 34.5 years. Following the conventional semen analysis, the nuclear vacuoles in motile spermatozoa were evaluated at 3700-6150 × magnification on an inverted microscope equipped with differential interference contrast optics. A large sperm nuclear vacuole (LNV) was defined as one or more vacuoles with a maximum diameter exhibiting > 50% width of the sperm head. We compared the differences in the proportion of spermatozoa with LNVs between two consecutive semen samples before treatment. Treatment-related differences in the number of LNVs were also analyzed. Student's t-test was used to perform the statistical analyses. No differences were observed in any semen parameters between the first and second ejaculates. On high-magnification microscopy, the proportion of spermatozoa with LNVs was 23.5% and 29.4% (p = 0.0220) in the first and second ejaculates, respectively in 33 patients. Among the 18 patients who underwent varicocele repair using a microsurgical subinguinal approach, the proportion of spermatozoa with LNVs at baseline, three, and six months after surgery was 27.7%, 12.0% (p = 0.0132 versus baseline), and 10.3% (p = 0.0226 versus baseline), respectively. After three months of medical treatment for male infertility in 28 patients, the proportion of spermatozoa with LNVs slightly decreased from 33.3% to 28.6% (p = 0.1276); however, it was not statistically significant. In conclusion, when multiple ejaculates were obtained, in the subset of male patients with infertility, the proportion of spermatozoa with LNVs could be different. The number of LNVs decreased following varicocele repair.

Observation of spermatozoa by a high-magnification microscope

Semen analyses are the primary tool for evaluating male infertility, as semen parameters are useful for predicting potential fertility. In the field of assisted reproductive technology (ART), the single best motile spermatozoon should be selected, especially when performing intracytoplasmic sperm injection (ICSI). In this context, the motile sperm organelle morphology examination (MSOME) was developed as a method of assessing the detailed morphology of motile spermatozoa in real time at a magnification of up to 6,300× on a video system. The use of ICSI with MSOME-selected sperm is called intracytoplasmic morphologically selected sperm injection (IMSI). IMSI improves the outcomes of ICSI. MSOME can be also applied to evaluate male infertility. Among MSOME parameters, the presence of sperm nuclear vacuoles is the most important finding. Large sperm nuclear vacuoles (LNV) are related not only to poor ART outcomes, but also to poor semen quality and sperm DNA damage, such as DNA fragmentation and chromatin condensation failure. It has been suggested that sperm head vacuoles are produced at earlier stages of sperm maturation. It is possible that the number of LNV can be decreased by surgical or medical treatment for male infertility. Therefore, the level of LNV has the potential to be used as an alternative parameter of semen quality and a new tool for evaluating the therapeutic effects of treatment in male patients with infertility.

Testicular volume discrepancy is associated with decreased semen quality in infertile Japanese males with varicoceles

Purpose

We retrospectively reviewed infertile Japanese males for testicular volume discrepancies (D) and semen parameters to evaluate whether left grade II-III varicoceles (V) cause testicular damage.

Methods

Seventy-seven patients who had idiopathic male infertility and 88 who had V without other causes of infertility were examined. We excluded cases of azoospermia. Testicular volume was measured using a punched-out orchidometer. D was defined as a size difference of at least 3 ml. The frequency of D was compared between the patients with and without V. The semen parameters were reviewed in association with D and V.

Results

The mean left and right testicular volumes were 19.4 and 20.1 ml, respectively (p < 0.001). D with a smaller left testis was more common in V+ cases than in V- cases (26.1 vs. 13.0%, p = 0.0351). The sperm count and motility were also significantly lower (p = 0.0213 and p = 0.0217, respectively) in the D+ patients with a smaller left testicular volume.

Conclusions

In the patients with V, D was more common than in those without V. The semen parameters were worse if D was present in the patients with V. These results indicated that V could induce testicular atrophy and negatively affect semen quality. Therefore, the ipsilateral reduced testicular volume is considered to be a sign of persisting testicular damage by V.

Sperm chromatin condensation in infertile men with varicocele before and after surgical repair

OBJECTIVE

To assess sperm chromatin integrity in infertile men with varicocele before and after surgical repair.

DESIGN

Prospective.

SETTING

Academic setting.

PATIENT(S)

Seventy-two infertile men with varicocele compared with 20 healthy fertile men.

INTERVENTION(S)

History taking, genital examination, semen analysis, sperm chromatin condensation assessment by aniline blue stain before and 3 months after varicocelectomy.

MAIN OUTCOME MEASURE(S)

Stained sperm heads (abnormal chromatin condensation) before and 3 months after varicocelectomy.

RESULT(S)

The mean percentage of aniline blue-stained sperm heads was significantly higher in infertile men with varicocele compared with fertile controls. The mean percentage of stained sperm heads was significantly decreased in infertile men with varicocele 3 months after surgery compared with the preoperative data. There was a significant negative correlation between percentage of stained sperm heads and normal morphology where nonsignificant correlation was elicited regarding sperm count and sperm motility.

CONCLUSION(S)

There is a significant increase of abnormal sperm chromatin condensation in infertile men with varicocele that is markedly improved after varicocelectomy.