Characterization of Circulating Pro- and Anti-Geronic Proteins and Peptides (R01)

Funding Agency:
National Institutes of Health

The goal of this FOA is to advance research on the underlying basis for the transfer (or transposition) of aging phenotypes observed between young and old rodents and discovered through heterochronic parabiosis. Examples of transposed phenotypes include reversal of cardiac hypertrophy, partial restoration of cognitive function, improved vascularization, and repair of skeletal muscle after cryo-injury (anti-geronic transposition), or as accelerated loss of cognitive function and neurogenesis (pro-geronic transposition). Other transposed phenotypes, as revealed solely through heterochronic parabiosis, may also be reported in the literature. There are also reports of candidate factors found in circulation that might be causally related to the transposition of these aging phenotypes; these are termed "circulating geronic factors" for purposes of this FOA. To date, these are proteins and peptides that pass between the young and old mice joined by parabiosis, due to anastomosis of their circulatory systems. Based on these novel findings and this novel experimental paradigm, the specific objective of this FOA is to test whether these candidate geronic factors are necessary for the transposition of aging phenotypes. The focus is on phenotypes transposed in heterochronic parabiosis and the candidate factors which are present and functional at physiological concentrations in circulation.

The outcome of research supported by this FOA should yield an improved understanding of the reversal or promotion of aging phenotypes that are affected by circulating geronic factors in the heterochronic parabiosis model system, and to narrow the range of candidate geronic factors through rigorous validation based on heterochronic parabiosis.


  • Letter of Intent Due Date(s): January 2, 2017
  • Application Due Date(s): February 2, 2017

RFA-AG-17-002 Expiration Date February 3, 2017

Agency Website



Amount Description

Application budgets are limited to a maximum of $350,000 per year direct costs.

The scope of the proposed project should determine the project period. The maximum project period is 4 years.

Funding Type





Environmental & Life Sciences
Medical - Basic Science
Medical - Clinical Science
Medical - Translational

External Deadline

February 2, 2017