journal

The 'beneficial' adipokines in reproduction and fertility

D B Campos^1,2, M-F Palin³, V Bordignon⁴ and B D Murphy¹

1. ¹Faculté de médecine vétérinaire, Centre de recherche en reproduction animale, Université de Montréal, Québec, Canada
2. ²Faculdade de Medicina Veterinária e Zootecnia, Departamento de Cirurgia, Universidade de São Paulo, Sao Paolo, Brasil
3. ³Dairy and Swine Research and Development Center, Agriculture and Agri-Food Canada, Lennoxville, Québec, Canada
4. ⁴Department of Animal Science, McGill University, Québec, Canada

Correspondence: Dr BD Murphy, Faculté de médecine vétérinaire, Centre de recherche en reproduction animale, Université de Montréal, CP 5000, 3200 rue Sicotte, St-Hyacinthe, Québec, Canada J2S7C6. E-mail: bruce.d.murphy@umontreal.ca

Received 8 April 2007; Revised 29 May 2007; Accepted 16 July 2007; Published online 9 October 2007.

Abstract

The objective of this study was to review the available information on the signaling proteins produced by adipose tissue in the context of their role in regulating reproductive processes, including ovarian and uterine function. It is well known that both obesity and excessive leanness are associated with reproductive dysfunction. Adipokines are cytokines predominately or exclusively expressed by adipose tissue that circulate and affect target tissues. Four known adipokines, adiponectin, visfatin/PBEF, omentin and vaspin, all increase tissue sensitivity to insulin, and are thus described as 'beneficial'. There is strong support for a role for adiponectin in the function of the ovary and placenta. There is evidence for direct effects of this adipokine on the late stages of folliculogenesis, and additive interactions of adiponectin with insulin and gonadotropins in inducing periovulatory changes in ovarian follicles. In addition, clinical and genomic studies associate hypoadiponectinemia with obesity-related reproductive disorders, including the polycystic ovarian syndrome. The roles for visfatin/PBEF, omentin and vaspin in reproduction remain to be established. The conclusion thus drawn is that the expression of insulin-sensitizing adipokines varies with adipose abundance. These adipokines have demonstrated both the potential effects on ovarian function and the possible effects on the formation of the placenta, acting through multiple mechanisms.

Keywords:

adipokines, adiponectin, insulin sensitivity, ovary, uterus, placenta