Combating diseases that are related to aging such as diabetes and cancer may in fact depend on scientists solving the mysteries regarding cellular and molecular processes that govern the process of aging. The fundamental theory remains that if ever the healthy part of a person’s life span can be prolonged, it may as a result postpone the onset of specific age-related diseases. In the quest to comprehend these molecular processes, the researchers of the University of Massachusetts Medical School have unveiled a crucial new DAF-16 isoform- DAF-16d/f- which works together with the other DAF-16 protein isoforms in order to control longevity.
The DAF-16, which forms part of the insulin signaling pathway, has a vital role to play in several of the biological processes in C. elegans, consisting of lipid metabolism, longevity, stress response and development, and is also the focal point of a complex network of proteins and genes. Studies that have been carried out in the past have identified the isoform, a varied kind of the same protein, DAF-16a as a regulator of longevity; hereditarily knocking down the DAF-16a shortens the life span of the C. elegans. In accordance to a recent study that appeared in the July issue of the online edition of Nature, Doctor Heidi A. Tissenbaum a PhD and an associate professor of molecular medicine along with his colleagues in the Program in Gene Function and Expression from the UMass Medical School, demonstrated that the isoform DAF-16d/f which has been recently found out, works in collaboration with DAF-16a in order to promote the lifespan of the organism.
Doctor Tissenbaum stated that up until now researchers have concentrated on the DAF-16b isoforms and DAF-16a. He explains that they have been able to demonstrate that DAF-16a along is not enough to regulate the life span. In order to progress, any further discussion regarding the aging process will need to take this new protein isoform into consideration.
Doctor Eun-soo Kwon, the lead author who is a post-doctoral fellow in the Tissenbaum laboratory, increased the expression of the DAF-16d/f and DAF-16a in C. elegans so as to the impact of the DAF-16d/f on life span. These researches have demonstrated that the worms which had overexpressed DAF-16d/f were the ones who lived longest. Extra experiments that have been carried out show that the worms which expressed DAF-16d/f showed more tolerance to heat stress during development and were able to store more fat.
The fact that the DAF-16 gene in the C. elegans is homologous to the FOXO gene found in mammals, it may offer indications regarding the issue of longevity in human beings. In accordance with Doctor Tissenbuam, the comprehension of molecular pathways of the DAF-16 as well as other genes will provide them with an insight into the process of aging both at the cellular and organism levels. He explains that as an individual age, when he reaches a certain point, something that triggers age related diseases occurs. If the researchers are successful to learn what these signals are, it will be possible to find a method to prolong the healthy portion of the individual’s lifespan as well as potentially postpone the onset of diseases that are related to aging like diabetes, cancer and Alzheimer’s.
Further investigation will look at whether a boost in life span is associated to the health of the worm. Tissenbaum said that it is possible that they are restoring life span, however they are not aware of the impacts of doing so. There is a need to see whether this increase in life span is of the healthy segment of the life span.
It should be noted that Sri Devi Narasimhan, a graduate student along with Dr. Kelvin Yen, a post doctoral colleague also made their contribution to this study.
Source: Science Daily and Escience News
Tue, Jul 13, 2010
Bioscience