Maternal Diet Programs Metabolism in Offspring
Thursday, October 28, 2010
Regular readers will recall the many posts on the issue of intra-uterine epigenetic programming, that is now believed by many to be one of the key drivers of the childhood obesity epidemic.
As more and more human and experimental evidence for this hypothesis accumulates, it is becoming increasingly evident that the intra-uterine environment may play a central role in determining the future risk of obesity in offspring (even much later in life).
This notion is further supported by an interesting study by Ricardo Orozco-Solís and colleagues from the Université de Nantes, France, published in the latest issue of PLoS One, showing that in rats, maternal nutrition during pregnancy is linked to long-lasting changes in nutrient sensing and energy homeostasis in the hypothalamus (the brain centre that regulates eating behaviours).
In this study, the researchers analyzed the profile of the hypothalamus transcriptome (the sum of all genes expressed as RNAs) in 180 days-old rats born to dams fed either a control (200 g/kg) or a low-protein (80 g/kg) diet through pregnancy and lactation.
From the almost 30,000 examined genes, around 700 were up-regulated and 300 down-regulated by early protein restriction.
Most interestingly, the researchers found that perinatal protein restriction permanently altered the expression of two gene clusters regulating a large number of common cellular processes.
While the first gene cluster includes several gate keeper genes regulating insulin signaling and nutrient sensing, the second cluster represents a functional network of nuclear receptors and co-regulators of transcription involved in the detection and use of lipid nutrients as fuel. This network also links temporal and nutritional cues to metabolism through their tight interaction with the circadian clock (in this context readers may recall the recent posts on the link between sleep and obesity).
As pointed out by the authors, these findings clearly show that (protein-) malnutrition during pregnancy and lactation may play a key role in epigenetically programming hypothalamic circuits regulating energy homeostasis.
As blogged before, the key to preventing childhood obesity may well lie in ensuring maternal nutrition and healthy body weights – once born, as with the proverbial horses, the kids may be out of the barn!
AMS
Hamilton, Ontario
Orozco-Solís R, Matos RJ, Guzmán-Quevedo O, Lopes de Souza S, Bihouée A, Houlgatte R, Manhães de Castro R, & Bolaños-Jiménez F (2010). Nutritional programming in the rat is linked to long-lasting changes in nutrient sensing and energy homeostasis in the hypothalamus. PloS one, 5 (10) PMID: 20975839
Thursday, October 28, 2010
I totally agree with the evidence given and recently we have submited a project of similar kind where we are going to challenge 4 different strains of rats with differing percent of fat per kg body weight to obeso genic diets and follow the epigenitic changes that can occur in them.The survival instinct for the fetus might have switched on the fat hording capacityin the offspring in earlier times ,million years back at a time when famine was the order of the day.In recent times, the pregnant mothers gorging on proceesed food(calorie dense, but nutritionally deficient) are sending the same signal to fortuses , who then switch on (methylation) the obesity gene , anticipating a hostile nutient defecint world out side.. the reason for such massive epidemic of obesity in affluent ( enrgy dense ) world today can certainly be attributed to our over dependence on processed food and lack of adequate physcial excersise to counter the accumulated exceess calories in the body interms of fat..
Friday, October 29, 2010
I wonder what you mean by malnutrition. Most westerners do not suffer from malnutrition in the sense that they don’t starve. Even those who eat who eat a lot of “processed food” probably have better nutrition than most of the world’s population. I have read a study about epigenetics that looked at the descendants of Dutch people who starved during the second world war, and those descendants were more prone to have lower birth weights and obesity. I am not clear how this happens when there is an abundance of food.
Saturday, October 30, 2010
@jennifer: Mal-nutrition simply means bad or poor nutrition. Of course Westerners do not lack calories, but they lack many important nutrients. Very few meet their needs for many vitamins, iron, protein and other important nutrients. So this post is not just about starvation, but really about poor nutrition that can influence the developing fetus in the womb.
AMS