Maternal exercise during pregnancy reduces risk of mammary tumorigenesis in rat offspring

Abstract

Breast cancer is the most common cancer among women. Emerging research indicates that modifying lifestyle factors during pregnancy may convey long-term health benefits to offspring. This study was designed to determine whether maternal exercise during pregnancy leads to reduced mammary tumorigenesis in female offspring. Pregnant rats were randomly assigned to exercised and sedentary groups, with the exercised group having free access to a running wheel and the sedentary group housed with a locked wheel during pregnancy. Female pups from exercised or sedentary dams were weaned at 21 days of age and fed a high fat diet without access to a running wheel. At 6 weeks, all pups were injected with the carcinogen N-methyl-N-nitrosourea (MNU). Mammary tumor development in all pups was monitored for 15 weeks. Pups from exercised dams had a substantially lower tumor incidence (42.9%) compared to pups from sedentary dams (100%). Neither tumor latency nor histological grade differed between the two groups. These data are the first to demonstrate that exercise during pregnancy potentiates reduced tumorigenesis in offspring. This study provides an important foundation towards developing more effective modes of behavior modification for cancer prevention.

Impact of Maternal Exercise during Pregnancy on Offspring Chronic Disease Susceptibility

“…Therefore, these preliminary data suggest that maternal exercise can reduce offspring mammary cancer risk (6). Camarillo et al hypothesized that maternal metabolism or factors released into the maternal circulation in response to exercise could lead to programming changes in the offspring, however, there is currently no data to support this claim (6). Future work should seek to elucidate the mechanisms by which protective effects of maternal exercise during pregnancy on offspring breast cancer risk occurs.…”

“…Mammary tumor development in all pups was monitored for 15 weeks. These data revealed that offspring from mothers who exercise during pregnancy have a mammary tumor incidence of 42.9% compared to 100% incidence in sedentary offspring (6). Therefore, these preliminary data suggest that maternal exercise can reduce offspring mammary cancer risk (6).…”

“…These data revealed that offspring from mothers who exercise during pregnancy have a mammary tumor incidence of 42.9% compared to 100% incidence in sedentary offspring (6). Therefore, these preliminary data suggest that maternal exercise can reduce offspring mammary cancer risk (6). Camarillo et al hypothesized that maternal metabolism or factors released into the maternal circulation in response to exercise could lead to programming changes in the offspring, however, there is currently no data to support this claim (6).…”

“…We hypothesized that maternal exercise during pregnancy would decrease the risk of breast cancer in offspring. Female rats were divided into two experimental groups during pregnancy: sedentary and voluntary wheel exercise (6). After weaning, female offspring from both sedentary and exercise mothers were fed a high fat diet.…”

Homage to the ‘H’ in developmental origins of health and disease

“…Ovarian weight was greater in light but not heavy neonates from exercised gilts Maternal exercise increased labeling index in heavy compared with light offspring in fetal but not neonatal or adolescent ovaries 60 Female Sprague Dawley rats Maternal exercise throughout pregnancy Pups from exercised dams had reduced mammary tumor incident after being placed at weaning on a HFD and exposed at 6 weeks of age to the carcinogen, N-methyl-N-nitrosourea…”