The second reference (below) has not yet been presented or publicized. However, I think it is important to recognize its integration with results of the 2007 study.

It seems likely that pheromones are stimulating restoration of the GnRH neuronal system both in males and in females. This would help to explain many reports of age-related health issues that go beyond mere sexual concerns--if a mammalian model is extended to humans.

Mak, G. K., Enwere, E. K., Gregg, C., Pakarainen, T., Poutanen, M., Huhtaniemi, I., et al. (2007). Male pheromone-stimulated neurogenesis in the adult female brain: possible role in mating behavior. Nat Neurosci, 1, 1.

ROCHESTER, J. R., CHUNG, W. C. G., & Tsai, P. (2009). Restoration of the GnRH system in aging male transgenic animals paired with females Paper presented at the Society for Neuroscience, Chicago, IL.

James V. Kohl
http://www.pheromones.com