The studies show that SIR2 has anti-ageing properties and can combat ageing and age-related diseases, but it works only on a low-calorie diet. The gene is found in living organisms, including human beings. The findings have been published in the January editions of Cell Reports and Molecular and Cellular Biology.
A low-calorie diet positively impacts this gene in the human body, which subsequently provides protection from diseases like diabetes, obesity, cancer, Alzheimer's, Parkinson's and cardiovascular diseases, and promotes "healthy ageing", says the study.
The gene has been at the centre of a global controversy for many years, with one school of scientists saying it extends lifespans, while another school disagrees. The arguments questioned the relevance of expensive drugs to mimic the effect of this gene to defy ageing and age-related diseases. The new study shows SIR2 has anti-ageing properties.
"Our study resolves the hotly debated controversy about the role of SIR2 as a longevity gene. We have found that it may slow down the ageing process, but it may not directly increase the number of years one lives. We found a low-calorie intake has a significant impact on SIR2 protein and helps the body combat age-related diseases," said Dr Ullas Kolthur from TIFR's Department of Biological Sciences, and principal investigator of the study.
In a liver equivalent tissue, the gene helps in achieving metabolic and energy balance, and mediates beneficial effects throughout the body. The study, however, showed that high-calorie food adversely impacted the gene, and it was not able to protect the body from a series of diseases associated with old age and bad eating habits.