Follicular Fluid Coenzyme Q10 Level in Women Undergoing Intracytoplasmic Sperm Injection

ICSI was first applied to human gametes in 1988, it was first used in cases of fertilization failure after standard IVF or when few sperm cells were available. The first pregnancies were reported in Belgium in 1992.It is a part of an in vitro fertilization (IVF) cycle and refers to a technique in which a single sperm is injected directly into the cytoplasm of a mature oocyte (Palermo et al.,1992).

Oocyte quality remains the most important issue during in vitro fertilization (IVF) cycles, it is affected mainly by age of woman and ovarian reserve (Trifunovic et al., 2004).

Oocyte maturation is a complex process including nuclear and cytoplasmic components. Mitochondria which is in the cytoplasm is the key regulator of energy production via oxidative phosphorylation process which is extremely important in oocyte maturation process. Any problem during oxidative phosphorylation might affect both the quality and DNA content of the oocytes (Ben-Meir et al., 2015).

Oxidative phosphorylation involves the action of the mitochondrial respiratory chain which consists of four complexes that are located in the inner mitochondrial membrane (May-Panloup et al., 2007). These are the NAD-linked dehydrogenase, Flavoproteins, Co-enzyme Q10, and cytochromes. Coenzyme Q10 (Ubiquinone) is structurally similar to vitamin E and vitamin K. It acts as a carrier of proton (H+) from flavoproteins to cytochrome (Bentinger et al., 2007).

Coenzyme Q10 is essential for stability and action of complex III (May-Panloup et al., 2007). It also participates in the transport of protons in the mitochondria to maintain the membrane potential and drive ATP formation through ATP synthetase so it has a critical role in cell growth and energy metabolism. One of the most important factors during oogenesis and oocyte maturation is energy consumption so CoQ10 was reported to improve development, hatching, cell proliferation, and ATP content of in vitro-produced bovine embryos (Gendelman et al., 2012; Stojkovic et al., 1999).