Potential role of p53 protein as a novelbiomarker of sperm quality, able to predict thesuccess of ART techniques. EcoFoodFertility Project

Introduction: Protein p53 is well known as “The guardian of genome”; it changes its concentration in human spermatozoa DNAin relation to the damage of the latter. It has been suggested thatthe role of the p53 ancestral gene was to ensure the integrity ofthe genomic germline and the fidelity of the evelopment process.The aim of this study is to evaluate if different concentrations of p53 protein in human spermatozoa could influence embryo quality and pregnancy rate and possibly representing a potential predictive marker of sperm quality for successful fertilization .Methods: From July 2013 to June 2017 we have examinatedretrospectively 79 couples with 2-5 years of infertility history.Males had an average age of 27 ± 7,5 years, sperm concentrationof 33,8 ± 6,2 mil/ml, progressive motility of 41,4 ± 8,3 and a typical morphology of 16,5 ± 3,5 according to Kruger’s method. We have divided the couples on the basis of p53 levels: Group A:0,35–1,65 ng/mil (21 males); Group B: 1,66–3,57 ng/mil (32 males);Group C: 3,58–14,53 ng/mil (26 males). We have evaluated thenumber of embryos at stage of 6–8 cells, btained at the third dayof embryo development, in these three different group. In order toevaluate the concentration of p53 protein, we first proceeded toa DNA extraction with forensic method and then to a quantification p53 protein with ELISA-immunoenzymatic assay, expressedin ng/million of spermatozoa.Results: We have observed different percentage of embryo development at stage of 6-8 cells in the third day and different pregnancy rate (PR):Group A: 101 embryos at 6-8 cells/ 147 total number of obtained embryos in this group (68,4%) and PR = 52,38%.Group B: 128/240 (53,5%); PR = 37,50%; Group C: 79/216 (36,1%);PR = 7,69%. These results support the hypothesis that an high con-centration of p53 in human sperm DNA is associated to a low percentage of embryos able to reach the stage of 6-8 cells in the third day of development and also to a lower pregnancy rate. So p53 levels can be considered as a predictive value to embryo development and pregnancy rate.Conclusions: Protein p53 is a sequence-specific transcriptionfactor that responds to a wide variety of stress signals (environ-mental insults and bad lifestyle) as we are investigating within theecofoodfertility project. Particularly quantitative research of p53could be considered as a novel biomarker of sperm quality, able topredict the success of ART echniques, and could open a new roadfor infertility diagnosis.