Pregnant mums who exercise may reduce diabetes risk in offspring with obese fathers

Victoria University preclinical research suggests that women who exercise before and during pregnancy can overcome the risk of their child developing diabetes that comes from having an obese father.

Exercise metabolism researchers Professor Glenn McConell and Dr Filippe Falcao-Tebas found that pregnant mothers who exercise can ‘reprogram’ the low insulin sensitivity and increased likelihood of diabetes that offspring of obese fathers are born with.

While it is well known that children of overweight mothers have an increased risk of diabetes, this study is the first to consider if mothers who exercise while pregnant can break a cycle of metabolic dysfunction caused by unhealthy fathers.

“We know that diet-induced obesity can affect sperm, but no study has looked at how a mum’s physical activity during the crucial gestation time can help fix a father’s bad input,” Professor McConell said.

The study involved healthy female rats breeding with male rats fed an obesity-inducing high-fat diet. One group of mums-to-be performed moderate exercise on a rodent treadmill five times a week for up to one hour, before and during gestation. Another control group remained sedentary.

Adult offspring were assessed for their responsiveness to glucose and insulin, their skeletal muscle glucose-handling, and the structure of their pancreas – the organ that produces the hormone insulin, which maintains healthy blood sugar levels.

The results showed offspring of obese fathers and sedentary mothers had low insulin sensitivity in skeletal muscle and low insulin secretion compared to the offspring whose mothers exercised.

The findings, likely to be relevant to humans, build on growing evidence suggesting that factors before and during pregnancy can affect the risk of chronic disease in offspring.

“The study provides preclinical evidence of strategies that could be used to prevent chronic diseases, and is a strong basis for further human studies, and, ultimately, the modification of public health policies,” said Professor McConell.

Dr Falcao-Tebas of Monash University conducted the research at VU under Professor McConell’s supervision as part of his PhD. He said the next step aims to use epigenetics – the study of mechanisms that later switch genes on and off – to investigate the skeletal muscle and pancreas genes of offspring born to exercising mothers.

The study, Maternal exercise attenuates the lower skeletal muscle glucose uptake and insulin secretion caused by paternal obesity in female adult rat offspring, has been peer-reviewed and accepted for publication by The Journal of Physiology.