Jetlag increases the risk of liver cancer in the same way as obesity does, according to new research on mice.
The researchers exposed mice to a longer period of erratic circadian rhythm and noticed an increased risk that these animals would develop liver cell cancer.
They believe that irregular sleep and eating habits disturb the synchronization between the liver and the hypothalamus. This increases the rate of mutations in the liver cells, which in turn increases the risk of cancer.
“Liver cancer is on the rise worldwide, and in human studies, we’ve now seen that patients can progress from fatty liver disease to liver cancer without any middle steps such as cirrhosis,” says David Moore to Science Daily. He is a professor of molecular and cellular biology and led the study with Associate Professor Loning Fu, both at Baylor College of Medicine in Houston, Texas.
“We knew we needed an animal model to examine this connection, and studies in the Fu Lab found that chronically jet-lagged mice developed liver cancer in a very similar way as that described for obese humans.”
Besides liver cancer, the mice exposed to irregular sleeping patterns also developed a range of conditions, including skin disorders and neurodegeneration. These were not seen in control mice, which had regular light and dark cycles. All mice received a normal diet.
Previous studies have shown a weak association between shift working women and an increased risk of breast cancer, but this is the first time it has been seen that an organ can be affected directly by irregular sleep.
The study has been published in the journal Cancer Cell.
Kettner et al. Circadian Homeostasis Metabolism of Liver Suppresses Hepatocarcinogenesis. Cancer Cell. 2016 DOI: org / 10.1016 / j.ccell.2016.10.007