How much do you know about caloric restriction and life span extension?

6 Questions

What is the percentage of caloric restriction that results in mice living about 30% longer than normal?

30% fewer calories

What organisms have shown an increase in lifespan with caloric restriction?

All organisms tested so far

What is epigenetics and how does it influence development and aging?

Epigenetics is the study of changes in gene expression that do not involve alterations to the DNA sequence. Epigenetic changes can influence many aspects of development and have been hypothesized to be involved in the regulation of aging.

What is the role of the SIR2 gene in the longevity effects of caloric restriction?

It plays a role

What are some advantages and drawbacks of using epigenetic treatments to control aging?

Epigenetic treatments have the advantage of being reversible and relatively stable, but they may also control large segments of the genome and must be used with great care.

What are some epigenetic factors that may affect aging?

Epigenetic changes may affect the structure of chromatin, histones, the positions of nucleosomes, and regulation of telomere length.

Study Notes

Caloric Restriction and Life Span Extension: Exploring the Science

Limiting food intake increases life span in all organisms tested so far.
Calorie restriction was first noted in yeast but also works in Caenorhabditis elegans and Drosophila melanogaster.
Mice consistently fed 30% fewer calories live about 30% longer than normal.
Caloric intake must be extremely restricted to have any effect in humans.
Short periods of extreme calorie restriction, such as a day of fasting, have shown benefits.
Time-restricted feeding or intermittent fasting, which involves eating only during an eight- or ten-hour period each day, might stave off high cholesterol, diabetes, and obesity.
Researchers are exploring whether the benefits of time-restricted eating might apply to humans as well as mice.
A related topic for investigation is whether long bouts of exercise may also extend life span.
Researchers have looked at the genetic basis of cell signaling pathways, such as the insulin/insulin-like growth factor (IGF-1) that operates in the IIS signaling pathway.
The SIR2 gene in yeast plays a role in the longevity effects of caloric restriction.
Sirtuins, the proteins encoded by SIR2 and its analogs, modify histones and other proteins and regulate important biological processes such as apoptosis, adipocyte and muscle cell differentiation, energy expenditure, and telomere length regulation.
Mitochondrial dysfunction has been implicated in a number of age-related diseases, including Alzheimer’s disease.