Abstract: Pharmaceutical compositions comprising a bromodomain and extraterminal domain (BET) inhibitor, methods, and systems for screening candidate substances or compounds thereof, for the prevention and/or treatment of age-related diseases, conditions, or disorders to a subject in need thereof. The invention also provides pharmaceutical compositions for treating or preventing an aging or age-related disease, condition, or disorder comprising a BET inhibitor and a pharmaceutically acceptable carrier.

Abstract: A method and system for screening candidate substances or compositions thereof, where mammalian cells containing a stain or detectable marker are introduced into the yolk sac of a fertilized egg, embryo, or larvae of a transparent and/or translucent fish model. The method and system may also be employed to identify detectable marker genes, marker proteins, or marker metabolites in the transplanted mammalian cells, where the marker may indicate, e.g., cellular senescence, non-senescence, excessive or abnormal proliferation, damaged DNA. Methods of treating a subject suffering from a disease, disorder, or condition resulting from cellular senescence, excessive or abnormal proliferation, or damaged DNA using the candidate substances or compositions thereof are provided.