RESUMO
BACKGROUND: Oxidative/nitrosative stress in the oocyte microenvironment could have an impact on intracytoplasmic sperm injection (ICSI) outcomes. The presence of reactive oxygen species (ROS) and reactive nitrogen species (RNS) can stimulate the secretion of pro-inflammatory cytokines, leading to chronic inflammation and potentially affecting embryo as well as oocyte quality. This study aimed to examine the relationship of lipid peroxidation [measured by the malondialdehyde (MDA) assay] with protein carbonyl [measured by the 2,4 dinitrophenylhydrazine (DNPH) assay] levels in cumulus cells (CCs), as well as nitric oxide (NO), peroxynitrite (ONOO-), and C-reactive protein (CRP) levels in follicular fluid (FF). The potential relationship of these levels with ICSI outcome was also evaluated. MATERIALS AND METHODS: In this prospective study, 63 FF samples and their corresponding CCs were collected for ICSI procedures. Spectrophotometry was used to assess levels of DNPH, MDA, NO, and ONOO-. CRP levels were evaluated using an immunoturbidimetric assay. RESULTS: The patients under 37 years with normal ovarian reserve had significantly lower levels of MDA, DNPH, NO, ONOO-, and CRP compared to those over 37 years. Additionally, we observed higher levels of MDA, DNPH, NO, ONOO-, and CRP in the group with an oocyte maturity rate of less than 60%. No significant difference was observed between the DNPH levels and factors such as infertility duration, embryo quality, pregnancy, or the number of retrieved oocytes. A higher level of MDA, NO, ONOO-, and CRP was found to be significantly related to the lower number of retrieved oocytes, longer periods of infertility, poor embryo quality, and negative pregnancy outcomes. CONCLUSION: Oxidative/nitrosative stress, linking to inflammation in the oocyte microenvironment, can be considered as a potentially useful biomarker for assessing the development and competence of oocytes and embryos and predicting ICSI outcomes.
RESUMO
OBJECTIVE: To compare the degree of efficiency between density gradient centrifugation (DGC) method and an extended horizontal swim-up (SU) method. METHODS: A total of 97 couples undergoing in vitro fertilization were enrolled in the study. Semen samples were divided into three aliquots and treated using DGC, extended horizontal SU, and combined methods. DNA fragmentation and chromatin decondensation were detected in native semen samples and their three corresponding aliquots. The corresponding mature oocytes of each semen sample were divided into two sibling cultures. The first sibling culture was microinjected with semen pellets from DGC, and the second sibling culture was microinjected with semen pellets from the combination of both methods. Fertilization rate and embryonic development were assessed at day 3. RESULTS: DNA fragmentation and chromatin decondensation was significantly low in DGC and extended horizontal SU samples; however, the rates of DNA fragmentation and chromatin decondensation were significantly lower in extended horizontal SU samples than in DGC samples. The lowest rates of DNA fragmentation and chromatin decondensation corresponded to the samples treated with both methods. The highest rates of DNA fragmentation and chromatin decondensation corresponded to the samples treated with DGC. No significant difference was found in the fertilization rate or day 3 embryos between sibling cultures. CONCLUSION: The combination of DGC and the extended horizontal SU techniques is best for giving the lowest rates of sperm DNA fragmentation and chromatin decondensation.