C-Phycocyanin Protects Against Low Fertility Through Inhibiting Reactive Oxygen Species In Aging Mice

Women over 30 have higher rates of infertility. For some reasons, such as environmental degradation or life stress, many female postpone childbearing age and a great proportion of the aged female become infertile. The reduction in quantity and deterioration in quality of oocytes is universal over the age of forty. In addition, poor oocyte quality is characterized by anomalies in the meiotic spindle, chromosome misalignment, oxidative stress, gene expression change, shortened telomeres and loss of cohesion. Oxidative stress occurs due to gradual accumulation of damage by free radicals that are generated during normal metabolism, and has been considered as one major mechanism underlying organism aging. Germ cells initiate meiosis and arrest at the dictyate stage of prophase I in the fetal ovary and the post-natal germ cells remain arrested for weeks to months in mice, and for 10-50 years in women. During this prolonged interval, reactive oxygen species (ROS) accumulates and negatively affects oocyte quality and quantity. ROS has a negative effect from oocyte maturation to fertilization, embryo development and pregnancy, and ROS is associated with the age-related decline in reproduction. Reducing oxidative stress by antioxidant supplementation could potentially reduce ROS-induced damage, thus maintaining oocyte and follicle number and quality. C-phycocyanin is a major biliprotein in Spirulina platensis that possesses antioxidant and radical-scavenging properties.Our results showed administration of PC could prevent oocyte fragmentation and aneuploidy, maintaining the integrity of cytoskeleton. Moreover, the expression of antioxidant genes, activity of SOD and MDA as well as distribution of mitochondria can be reversed by PC. PC exerted its benefit via inhibiting the production of ROS and subsequent eliminating apoptosis. Finally, significant increase of little size was observed after PC administration in D-galactose-induced aging mice.Our study demonstrates for the first time that D-galactose-induced impaired female reproductive capability can be partially rescued by PC through an antioxidant mechanism.