Adriamycin induces H2AX phosphorylation in human spermatozoa

Aim： To investigate whether adriamycin induces DNA damage and the formation of γH2AX （the phosphorylated form of histone H2AX） foci in mature spermatozoa. Methods： Human spermatozoa were treated with adriamycin at different concentrations, γH2AX was analyzed by immunofluorescent staining and flow cytometry and doublestrand breaks （DSB） were detected by the comet assay. Results： The neutral comet assay revealed that the treatment with adriamycin at 2 μg/mL for different times （0.5, 2, 8 and 24 h）, or for 8 h at different concentrations （0,4, 2 and 10 μg/mL）, induced significant DSB in spermatozoa. Immunofluorent staining and flow cytometry showed that the expression of γH2AX was increased in a dose-dependent and time-dependant manner after the treatment of adriamycin. Adriamycin also induced the concurrent appearance of DNA maintenance/repair proteins RAD50 and 53BP 1 with γH2AX in spermatozoa. Wortmannin, an inhibitor of the phosphatidylinositol 3-kinase （PI3K） family, abolished the co-appearance of these two proteins with γH2AX. Conclusion： Human mature spermatozoa have the same response to DSB-induced H2AX phosphorylation and subsequent recruitment of DNA maintenance/ repair proteins as somatic cells.

Preimplantation genetic testing guidelines of International Society of Reproductive Genetics

The International Society of Reproductive Genetics(ISRG)assembled a workgroup made up of clinicians,clinical laboratory directors,and scientists for the purpose of creating the guidelines for preimplantation genetic testing(PGT).The most up-to-date information and clinical insights for the optimal PGT practice were incorporated in these guidelines.Recommendations are provided for embryologists,medical geneticists,clinical laboratorians,and other healthcare providers to improve the wellbeing of patients seeking assisted reproductive treatment and their offspring.

Review:Mitochondrial functions on oocytes and preimplantation embryos

Oocyte quality has long been considered as a main limiting factor for in vitro fertilization(IVF) . In the past decade,extensive observations demonstrated that the mitochondrion plays a vital role in the oocyte cytoplasm,for it can provide adenosine triphosphate(ATP) for fertilization and preimplantation embryo development and also act as stores of intracellular calcium and proapoptotic factors. During the oocyte maturation,mitochondria are characterized by distinct changes of their distribution pattern from being homogeneous to heterogeneous,which is correlated with the cumulus apoptosis. Oocyte quality decreases with the increasing maternal age. Recent studies have shown that low quality oocytes have some age-related dysfunctions,which include the decrease in mitochondrial membrane potential,increase of mitochondrial DNA(mtDNA) damages,chromosomal aneuploidies,the incidence of apoptosis,and changes in mitochondrial gene expression. All these dysfunctions may cause a high level of developmental retardation and arrest of preimplantation embryos. It has been suggested that these mitochondrial changes may arise from excessive reactive oxygen species(ROS) that is closely associated with the oxidative energy production or calcium overload,which may trigger permeability transition pore opening and subsequent apoptosis. Therefore,mitochondria can be seen as signs for oocyte quality evaluation,and it is possible that the oocyte quality can be improved by enhancing the physical function of mitochondria. Here we reviewed recent advances in mitochondrial functions on oocytes.

Different sperm sources and parameters can influence intracytoplasmic sperm injection outcomes before embryo implantation

To evaluate the effects of sperm with different parameters and sources on the outcomes of intracytoplasmic sperm injection (ICSI), 1972 ICSI cycles were analyzed retrospectively. Groups 1 to 5 were composed of cycles using ejaculated sperm and were grouped according to sperm quantity, quality, and morphology into normal (288 cycles), or mild (329 cycles), moderate (522 cycles), severe (332 cycles), and extremely severe (171 cycles) oligozoospermia and/or asthenozoospermia and/or teratozoospermia (OAT) groups. Group 6 was composed of 250 cycles using testicular or epididymal sperm, and Group 7 consisted of 80 cycles using frozen-thawed sperm. We found that fertilization rates were gradually reduced from Groups 1 to 6, and reached statistical difference in Groups 5 and 6 (P<0.05). The high-quality embryo rate was higher in Group 1 than in Groups 2, 3, 5, 6, and 7 (P<0.05). No statistical differences were observed in the rates of embryo cleavage, clinical pregnancy, miscarriage, live-birth, premature birth, low birth weight, weeks of premature birth, average birth weight, or sex ratio for all seven groups (P>0.05). A total of nine cases of malformation were observed, with a malformation rate of 1.25% (9/719). In conclusion, different sperm sources and parameters can affect ICSI outcomes before embryo implantation. A full assessment of offspring malformation will require further study using a larger sample size.

Basonuclin 1 deficiency causes testicular premature aging: BNC1 cooperates with TAF7L to regulate spermatogenesis

Basonuclin(BNC1)is expressed primarily in proliferative keratinocytes and gametogenic cells.However,its roles in spermatogenesis and testicular aging were not dear.Previously we discovered a heterozygous BNC1 truncation mutation in a premature ovarian insufficiency pedigree.In this study,we found that male mice carrying the truncation mutation exhibited progressively fertility loss and testicular premature aging.Genome-wide expression profiling and direct binding studies(by chromatin immunoprecipitation sequencing)with BNC1 in mouse testis identified several spermatogenesis-specific gene promoters targeted by BNC1 including kelch-like family member 10(Klhl1O),testis expressed 14(Tex14)9 and spermatogenesis and centriole associated 1(Spatcl).Moreover,biochemical analysis showed that BNC1 was associated with TATA-box binding protein-associated factor 7 like(TAF7L),a germ cell-specific paralogue of the transcription factor IID subunit TAF7,both in vitro and in testis,suggesting that BNC1 might directly cooperate with TAF7L to regulate spermatogenesis.The truncation mutation disabled nuclear translocation of the BNC1/TAF7L complex,thus,disturbing expression of related genes and leading to testicular premature aging.Similarly,expressions of Y-box-binding protein 2(YBX2),outer dense fiber of sperm tails 1(ODfl),and glyceraldehyde-3-phosphate dehydrogenase,spermatogenic(GAPDHS)were significantly decreased in the testis of men with non-obstructive azoospermia.The present study adds to the understanding of the physiology of male reproductive aging and the mechanism of spermatogenic failure in infertile men.

Application and Challenge of Preimplantation Genetic Testing in Reproductive Medicine

There has been a very rapid development in the area of preimplantation genetic testing(PGT)since the first baby applied PGT technology in the world was born in the last 30 years.As an alternative treatment of prenatal diagnosis,the transfer of the fetus with normal testing result has benefited many families.PGT is mainly classified into PGT for aneuploidies(PGT-A),PGT for chromosomal structural rearrangement(PGT-SR),and PGT for monogenic/single-gene defects(PGT-M).Here,we reviewed the application,development,limitations,and challenges of the current PGT in reproductive medicine.