Protects
against aging-associated diseases
University
of California - Irvine
In
a University of California, Irvine-led study, researchers found evidence that
fasting affects circadian clocks in the liver and skeletal muscle, causing them
to rewire their metabolism, which can ultimately lead to improved health and
protection against aging-associated diseases. The study was published recently in Cell Reports.
The
circadian clock operates within the body and its organs as intrinsic
time-keeping machinery to preserve homeostasis in response to the changing
environment.
And, while food is known to influence clocks in peripheral tissues, it was unclear, until now, how the lack of food influences clock function and ultimately affects the body.
And, while food is known to influence clocks in peripheral tissues, it was unclear, until now, how the lack of food influences clock function and ultimately affects the body.
"We discovered fasting influences the circadian clock and fasting-driven cellular responses, which together work to achieve fasting-specific temporal gene regulation," said lead author Paolo Sassone-Corsi, Donald Bren Professor of Biological Chemistry at UCI's School of Medicine. "Skeletal muscle, for example, appears to be twice as responsive to fasting as the liver."
The
research was conducted using mice, which were subjected to 24-hour periods of
fasting. While fasting, researchers noted the mice exhibited a reduction in
oxygen consumption (VO2), respiratory exchange ratio (RER), and energy expenditure,
all of which were completely abolished by refeeding, which parallels results
observed in humans.
"The
reorganization of gene regulation by fasting could prime the genome to a more
permissive state to anticipate upcoming food intake and thereby drive a new
rhythmic cycle of gene expression. In other words, fasting is able to
essentially reprogram a variety of cellular responses. Therefore, optimal
fasting in a timed manner would be strategic to positively affect cellular
functions and ultimately benefiting health and protecting against
aging-associated diseases."
This
study opens new avenues of investigation that could ultimately lead to the
development of nutritional strategies to improve health in humans.
Sassone-Corsi
first showed the circadian rhythm-metabolism link some 10 years ago,
identifying the metabolic pathways through which circadian proteins sense
energy levels in cells.