Can we use incubators with atmospheric oxygen tension in the first phase of in vitro fertilization? A retrospective analysis

Tang

Journal Cellular Physiology

et al. 2021

195

112

In a healthy body, reactive oxygen species (ROS) and antioxidants remain balanced. When the balance is broken toward an overabundance of ROS, oxidative stress appears and may lead to oocyte aging. Oocyte aging is mainly reflected as the gradual decrease of oocyte quantity and quality. Here, we aim to review the relationship between oxidative stress and oocyte aging. First, we introduced that the defective mitochondria, the age‐related ovarian aging, the repeated ovulation, and the high‐oxygen environment were the ovarian sources of ROS in vivo and in vitro. And we also introduced other sources of ROS accumulation in ovaries, such as overweight and unhealthy lifestyles. Then, we figured that oxidative stress may act as the “initiator” for oocyte aging and reproductive pathology, which specifically causes follicular abnormally atresia, abnormal meiosis, lower fertilization rate, delayed embryonic development, and reproductive disease, including polycystic ovary syndrome and ovary endometriosis cyst. Finally, we discussed current strategies for delaying oocyte aging. We introduced three autophagy antioxidant pathways like Beclin‐VPS34‐Atg14, adenosine 5‘‐monophosphate (AMP)‐activated protein kinase/mammalian target of rapamycin (AMPK/mTOR), and p62‐Keap1‐Nrf2. And we also describe the different antioxidants used to combat oocyte aging. In addition, the hypoxic (5% O2) culture environment for oocytes avoiding oxidative stress in vitro. So, this review not only contribute to our general understanding of oxidative stress and oocyte aging but also lay the foundations for the therapies to treat premature ovarian failure and oocyte aging in women.

Section: Sources Of Reactive Oxygen Species In Vivo and In Vitromentioning

confidence: 99%

Section: The Strategy For Preventing or Delaying Oxidative Stress In Oocytesmentioning

confidence: 99%

Oxidative stress in oocyte aging and female reproduction

Tang

Journal Cellular Physiology

et al. 2021

195

112

“…A damaged biomolecule system including oxidized proteins, changed membrane lipid composition as well as impaired DNA,all together, triggers a series downstream cascades and ultimately impact on oocyte meiosis, follicular atresia, GC apoptosis as well as other cell activities, moreover, together with additional affected mechanism associated with mitochondria injury, telomere shortening and apoptosis (reviewed by [80][81][82]). Besides for natural ovarian aging process, the oocytes might encounter another circumstance with more sever threat caused by ROS, which is ubiquitous in IVF (in vitro fertilization), where the oocyte has to experience a set of operation in a hyperoxia environment (with a 5% CO2 and 20% O2 atmosphere at assisted reproduction laboratories) before returning to human uterus (with a 2%-8% oxygen tension) [83]. Cultivated in such a hyperoxia environment might induce oxygen toxicity that is able to drive cytoplasmic aberrations including aggregation of cytoskeleton components and endoplasmic reticulum condensates, which should be avoid to the greatest extent to maintain embryo quality [84].…”

Section: Oxidative Stress Caused By Ros and Agesmentioning

confidence: 99%

Mechanisms of ovarian aging in women: a review

Xiang

2023

J Ovarian Res

Ovarian aging is a natural and physiological aging process characterized by loss of quantity and quality of oocyte or follicular pool. As it is generally accepted that women are born with a finite follicle pool that will go through constant decline without renewing, which, together with decreased oocyte quality, makes a severe situation for women who is of advanced age but desperate for a healthy baby. The aim of our review was to investigate mechanisms leading to ovarian aging by discussing both extra- and intra- ovarian factors and to identify genetic characteristics of ovarian aging. The mechanisms were identified as both extra-ovarian alternation of hypothalamic–pituitary-ovarian axis and intra-ovarian alternation of ovary itself, including telomere, mitochondria, oxidative stress, DNA damage, protein homeostasis, aneuploidy, apoptosis and autophagy. Moreover, here we reviewed related Genome-wide association studies (GWAS studies) from 2009 to 2021 and next generation sequencing (NGS) studies of primary ovarian insufficiency (POI) in order to describe genetic characteristics of ovarian aging. It is reasonable to wish more reliable anti-aging interventions for ovarian aging as the exploration of mechanisms and genetics being progressing.

“…In a total of n = 402 ART cycles, Guarneri et al specifically evaluated the use of two different oxygen concentrations (atmospheric versus low oxygen) during oocyte culture from recovery until decumulation on day 1, followed by use of low oxygen concentration (5%) until transfer. Interestingly, cumulus-intact oocytes cultured in atmospheric oxygen tension for ~20 h for c-IVF resulted in a comparable number of transferred/vitrified embryos from the inseminated oocytes, cumulative clinical pregnancy rate and cumulative live birth rate per cycle compared to the oocytes cultured under 5% oxygen level from gamete retrieval to embryo transfer [ 53 ]. Although evidence-based data strongly indicate that culturing embryos in low oxygen concentration improves embryo utilization rate and increases the chance of pregnancy [ 50 , 54 ], the potential antioxidant activity of the cumulus cells present during the first step of c-IVF needs to be further investigated.…”

Section: Conventional Ivf: Technical Detailsmentioning

confidence: 99%

Opportunities and Limits of Conventional IVF versus ICSI: It Is Time to Come off the Fence

Balli

Cecchele²,

Pisaturo³

et al. 2022

JCM

Self Cite

Conventional IVF (c-IVF) is one of the most practiced assisted reproductive technology (ART) approaches used worldwide. However, in the last years, the number of c-IVF procedures has dropped dramatically in favor of intracytoplasmic sperm injection (ICSI) in cases of non-male-related infertility. In this review, we have outlined advantages and disadvantages associated with c-IVF, highlighting the essential steps governing its success, its limitations, the methodology differences among laboratories and the technical progress. In addition, we have debated recent insights into fundamental questions, including indications regarding maternal age, decreased ovarian reserve, endometriosis, autoimmunity, single oocyte retrieval-cases as well as preimplantation genetic testing cycles. The “overuse” of ICSI procedures in several clinical situations of ART has been critically discussed. These insights will provide a framework for a better understanding of opportunities associated with human c-IVF and for best practice guidelines applicability in the reproductive medicine field.