Sperm stimulants can improve fertilization rates in male-factor cases undergoing IVF to the same extent as micromanipulation by partial zona dissection (PZD) or subzonal sperm insemination (SUZI): a randomized controlled study

Is there a role for phosphodiesterase inhibitors in the treatment of male subfertility?

Intracytoplasmic sperm injection (ICSI) is frequently used to overcome severe deficits in semen quality. Concerns, however, are arising over its increasing use for non-male factor infertility. Moreover, increased risk of cardiovascular disease, congenital abnormalities, aneuploidies and childhood cancers have all been reported in the literature in relation to ICSI and it is possible that the quality of sperm chosen for injection may be an important factor in these unwanted outcomes. Given the wider adoption of ICSI to treat beyond the requirements of male infertility alone, research focussed on alternative methods to diagnose and treat the infertile couple is gaining increasing attention. This review focuses on the information available to date on the use of non-selective phosphodiesterase inhibitors (PDEI), specifically pentoxifylline (PF), caffeine (CF) and theophylline (TP) to stimulate sperm motility, thereby potentially reducing the need for ICSI in certain patient groups who may benefit from either expectant management or from a less stressful, minimally invasive and inexpensive treatment such as intrauterine insemination (IUI). The review focuses firstly on the mechanism of action of PDEI followed by treatment effects on sperm parameters such as motility and hyperactivated motility and sperm DNA integrity. Specific clinical implications are discussed that outline the potential role of PDEI in clinical practice and highlights areas in need of further research.

The Role of G22 A Adenosine Deaminase 1 Gene Polymorphism and the Activities of ADA Isoenzymes in Fertile and Infertile Men

OBJECTIVE

To evaluate frequency distribution of adenosine deaminase 1 (ADA1) G22 A alleles and genotypes in fertile and infertile men.

METHODS

In this study we evaluate frequency distribution of ADA1 G22 A alleles and genotypes in 200 fertile and 200 infertile men. The polymerase chain reaction-restriction fragment length polymorphism technique was used for determining ADA1 G22 A variants. In addition, ADA isoenzymes activities (ADA1 and ADA2) were measured using colorimetric method.

RESULTS

The frequency of GG genotype was significantly higher and GA genotype was lower in infertile males compared with fertile men (P = .048 and P = .045, respectively). However, there was not any noticeable difference in allele distribution between groups (P >.05). Based on logistic regression analysis, the GA genotype has a protective role and can decrease the risk of male infertility 1.7 times (P = .046). There were significantly higher activities of ADAT and its isoenzymes in infertile males compared with fertile men (P <.05). Also, the ADA1 activity with GG genotype was higher than GA carriers in all population (P = .001).

CONCLUSION

Our results revealed that the activity of ADA isoenzymes and distribution of ADA1 G22 A genotypes were different among fertile and infertile men and more likely the GA genotype, which had lower ADA1 activity and was higher in fertile men is a protective factor against infertility.

Phosphatidylinositol 3-kinase inhibition enhances human sperm motility and sperm-zona pellucida binding

Various signalling pathways are involved in the regulation of sperm motility, capacitation, acrosome reaction and sperm-zona binding. Recent data pointed out an important role for phosphatidylinositol 3-kinase (PI3K) in human sperm motility. However, no study as of yet has been carried out to determine the effect of sperm treatment with the PI3K inhibitor LY294002 on other sperm parameters. In the present study, we investigated the role of PI3K on human sperm motility, acrosome reaction and sperm-oocyte binding by using this inhibitor. We demonstrate that in vitro incubation of washed unselected spermatozoa with LY294002 increased the percentage motility and progressive motility in asthenozoospermia patients as evaluated by computer-aided sperm analysis. The compound furthermore did not influence the acrosome reaction, whilst it (further) slightly enhanced sperm-oocyte binding. Our results therefore imply that PI3K negatively affects sperm motility and oocyte binding and might suggest a possible therapeutic role for PI3K inhibitors in the treatment regime for asthenozoospermia.