Luisa Maria Cion conducted an interesting study showing that long-term lactating rodent pups are less likely to become obese during adulthood, even when they are exposed to a high-fat diet. Published in the journal Nature Metabolism, the results of this study, carried out between various organizational centers, such as the Santiago de Compostela Health Research Institute (IDIS) and the CIBER for Physiopathology of Obesity and Nutrition (CIBROBN), may represent an important milestone. Huh. In the prevention and treatment of obesity, as Luisa Maria Cione explains.
Last week you published a study in the journal Nature Metabolism explaining why prolonged breastfeeding is a protective factor for obesity in adulthood. How did you get this union?Previously, there were already studies in humans that related longer breast-feeding with a lower risk of obesity and other related pathologies, but it is true that there are other studies that have not been able to find this relationship, and this would be because Because obesity is multifactorial. There are some known as ‘confounding factors’ that affect body composition, such as the mother’s own body composition, the habits of the mother and child, genetics, exercise… all these factors affect breastfeeding. Making it difficult to directly relate obesity to the nursing mother. To achieve this, for this study we designed an animal model in which all these confounding factors are controlled for: all animals have the same genetic background, their mothers have the same weight, and they are of normal weight. within, they all have the same diet, they move within the same space … After controlling for these confounding factors, we only breastfed a few of them for a longer period of time and compared them with those of people who had a standard breastfeeding period.
What you have discovered is the mechanism that interferes with the obesity protection of long-term breastfeeding. Which one is that?Yes, the interesting thing about this study is that we found the mechanism involved in this protective factor. We observed that long-term overfeeding modulates various systems at the level of peripheral tissues, such as liver or adipose tissue, and also the brain. Specifically, in the Nature article, we remarked that prolonged breast-feeding increases the production of a protein called FGF21 in the liver. This protein is able to reach the brain, activate the dopaminergic system and act on a very specific area of the brain that is related to body weight, it causes activity in brown adipose tissue and animals burn more energy. Thus, even if they ate the same, animals in which this mechanism was activated, despite eating a diet rich in fat, burned more fat and had less body weight and less obesity.
Animals that had this mechanism activated, despite eating a diet rich in fat, burned more fat and had less body weight and less obesity
How long did you breastfeed in this study?We applied the animal model and, if it was to breastfeed normally for the past three weeks, we extended it for another week, leaving the animals with their mothers for four weeks. With just one week, we saw that the effects of this protein last into adulthood. Although it is difficult to extrapolate, we roughly calculate that one week in these animals is equivalent to breastfeeding for about three months in humans. Of course, this is just a calculation, studies in humans would need to be replicated to verify this and give more accurate data. In fact, we are already starting studies with the pediatric unit of the clinical hospital in Santiago.
Can it be said on the basis of this study that if we had higher breastfeeding rates for a longer period of time, there would be less number of obese adults?We cannot say that babies who have been breastfed for a long time will be safe from obesity because, as I told you in the beginning, obesity is influenced by many other factors, but we can say that we have According to the data extracted from our study and if we manage to extrapolate them to humans, they will have a low risk of suffering from obesity. That’s the idea we believe we should stick with, that longer-term breastfeeding lowers the risk of obesity.
We want to show in preclinical studies whether we can reverse obesity with any of the proteins we found
If tested in humans, what could this discovery mean for the knowledge and treatment of obesity?If it is confirmed that this is the mechanism that also intervenes in humans, it could serve, on the one hand, from a preventive point of view, to assess which babies, based on the type and length of breastfeeding Will be more vulnerable, suffer from obesity in future. And on the other hand, it may lead to treatment against obesity.
Using the FGF21 protein?Yes, that’s what we want to test in preclinical studies, if treatments based on this protein, or other candidates we have, can serve as therapeutic targets for treating obesity in adulthood. For example, another possibility would be how to reap the benefits of this physiological process in children who, for whatever reason, cannot feed breast milk or continue to breastfeed. This could be, for example, enriching powdered milk with nutritional supplements…
What is the next step?Following the findings in animal models, we wish to continue this line of research and we already have candidates for continuing studies with humans. In addition, we also wish to initiate preclinical studies in adult obese animals to see if we can reverse obesity by administering any of the proteins found in animal studies. Because it’s not just this protein, FGF21, we have over 100 proteins that could have this effect and that we want to test, but we need funding for that.
What other research do you do at CIBEROBN on breastfeeding or obesity?In the group we have different lines of research. Breastfeeding is one of them, but we also work a lot on the relationship between peripheral organs, such as the gastrointestinal tract, liver, adipose tissue … and the brain, and how energy balance and body weight are regulated by the relationship. between the peripheral organs and the central nervous system… The aim of these studies is to discover potential therapeutic targets against obesity.