How Fasting Can Improve Overall Health and Protect Against Aging-Associated Diseases

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.

“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.”

Schematic overview of the interplay between the central and peripheral circadian clocks. Waves symbolises circadian regulation. RHT: retinohypothalamic tract; SCN: suprachiasmatic nucleus; sPVZ: subparaventricular zone; POA: preoptic area; BNST: bed nucleus of the stria terminalis; ARC: arcuate nucleus; DMH: dorsomedial hypothalamus; PVN: paraventricular nucleus; ACTH: adrenocorticotropic hormone; HMGCoAR: HMG-CoA Reductase; FAS: Fatty Acid Synthase; ACC: acetyl-CoA carboxylase; ApoAIV: apolipoprotein AIV; FABP4: fatty-acid-binding-protein 4; CYP7A1: cholesterol-7α-hydroxylase; DGAT2: diacylglycerol acyltransferase 2; MTP: microsomal triglyceride transfer protein; SCD-1: stearoyl-CoA desaturase-1; NPC1L1: Niemann-Pick C1-like 1.

Credit: Gnocchi D, Pedrelli M, Hurt-Camejo E, Parini P. Lipids around the Clock: Focus on Circadian Rhythms and Lipid Metabolism. Graham A, ed. Biology. 2015;4(1):104-132. doi:10.3390/biology4010104. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4381220/ Wikimedia Commons