The study of the human aging process is an important but difficult one. Since the time it takes to study the lifespan of a human takes almost a decade, making progress in the field is difficult.
Studies have been done on other species that share certain attributes with humans, but the results are not always useful. Worms, mice and primates have been studied, and that information has been studied in conjunction with human aging. However, a new animal has surfaced that might be the ideal test subject.
Discovered in 1968, the turquoise killifish is native to East Africa. What makes the killifish unique is the length of its lifespan, or rather, the shortness of it. Killifish live in ponds that develop during East Africa’s rainy season. The eggs laid by the previous season’s killifish wait in suspended animation until the pond forms again. The killifish grows to its full size of 2.5 inches in only 40 days. In about four months, the killifish are born, grow to adulthood, mate and lay fertile eggs for next season, then die. This abbreviated lifespan is just one of the reasons the killifish is the ideal test subject for the study of human aging.
Though mice live only four years, there are still limits as to what can be learned from their aging process. Nematode worms are also used to study aging, but there are physical traits humans have that worms do not, such as bones, leaving more gaps in the research. This is where the accelerated life span of the killifish comes into play. The killifish has a lifespan of only four months, greatly increasing the amount of information that can be gathered about the aging process over the years. Unlike nematode worms, the killifish is an invertebrate, as well as sharing other physical characteristics that humans have. They have an adaptive immune system, blood, and even similar stem cell biology, making them an excellent candidate for human aging studies.
The short life span of the killifish means that scientists will be able to gather information much faster than with mice, and information more pertinent to humans than nematode worms. The prolific reproduction rate of the killifish means that researchers can raise and study hundreds of killifish offspring and their various genetic makeups over the course of only a few months. Not only is more efficient and productive research of the aging process made possible by the killifish, but the testing of anti-aging drugs can be done with a much faster conclusion than other methods. An anti-aging drug that adds two weeks to the life of a killifish could add years to a human life.
Anne Brunet and her colleagues at Stanford University are researchers that are on the edge of a major breakthrough in the study of human aging using killifish. Once they begin using killifish in multiple studies by multiple teams of researchers, the increase of information on the aging process will be greatly accelerated. Many are looking forward to the wealth of information that this new type of study will bring.
Photo credit: brian.gratwicke / Foter / CC BY