Chorionic Gonadotropin and Its Receptor Are Both Expressed in Human Retina, Possible Implications in Normal and Pathological Conditions

PLoS One. 2012;7(12):e52567. doi: 10.1371/journal.pone.0052567. Epub 2012 Dec 19.

Abstract

Extra-gonadal role of gonadotropins has been re-evaluated over the last 20 years. In addition to pituitary secretion of luteinizing hormone (LH) and follicle stimulating hormone (FSH), the CNS has been clearly identified as a source of hCG acting locally to influence behaviour. Here we demonstrated that human retina is producing this gonadotropin that acts as a neuroactive molecule. Müller glial and retinal pigmented epithelial (RPE) cells are producing hCG that may affects neighbour cells expressing its receptor, namely cone photoreceptors. It was previously described that amacrine and retinal ganglion (RGC) cells are targets of the gonadotropin releasing hormone that control the secretion of all gonadotropins. Therefore our findings suggest that a complex neuroendocrine circuit exists in the retina, involving hCG secreting cells (glial and RPE), hCG targets (photoreceptors) and hCG-release controlling cells (amacrine and RGC). The exact physiological functions of this circuit have still to be identified, but the proliferation of photoreceptor-derived tumor induced by hCG demonstrated the need to control this neuroendocrine loop.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blotting, Western
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Chorionic Gonadotropin, beta Subunit, Human / genetics
  • Chorionic Gonadotropin, beta Subunit, Human / metabolism*
  • Chorionic Gonadotropin, beta Subunit, Human / pharmacology
  • Gene Expression Regulation
  • Humans
  • Protein Transport
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Receptors, LH / metabolism*
  • Retina / metabolism*
  • Retina / pathology*
  • Retinoblastoma / metabolism
  • Retinoblastoma / pathology

Substances

  • Chorionic Gonadotropin, beta Subunit, Human
  • RNA, Messenger
  • Receptors, LH

Grant support

This work was supported by the German foundation “Stifterverband für die Deutsche Wissenschaft” (to TC). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.