New aspect on the regulation of in vitro oocyte maturation: role of the obesity, neuropeptides and adipokines.

Oocyte quality determinants and nuclear and cytoplasmic maturation establish essential processes for fertilization and further development of the conceptus. Moreover, female fertility is strongly dependent on the metabolic status of the organism. Numerous sources indicate that obesity impairs ovarian function including oocyte physiology by inhibiting nuclear maturation, stimulating lipotoxicity and inflammation, enabling cumulus cells apoptosis, promoting reactive oxygen species formation and ultimately imposing pathogenic effects on mitochondria leading to infertility. Whereas, the number of overweight and obese individuals has reached alarming levels over the past decades, what is more, by 2030, the prevalence of overweight and obesity might reach 65.3% in adults in China and 78% in the USA. Thus, relationships between reproduction and metabolism are being intensively studied to prevent obesity-induced infertility. The metabolic markers of oocyte condition and function are adipokines and neuropeptides, which regulate food intake, lipid and glucose metabolism, insulin resistance and impart significant influences on reproduction. Thus, in this review, we focus on interrelationships between obesity, oocyte maturation and the role of selected neuropeptides and adipokines including leptin, adiponectin, kisspeptin, nesfatin-1, phoenixin, visfatin, chemerin and vaspin.