Much is said about the influence of maternal diet on the health and metabolism of children and it is common for women to change their eating habits during pregnancy and lactation periods.
Now, a study published in the journal Food Research International suggests that the quality of what parents consume should also be observed, as it can influence the gut-brain axis of the offspring, a system that connects the two organs and is related to metabolic problems, including obesity.
The research work, funded by Fapesp through two projects (19/09724-8 and 17/09646-1), analyzed and measured proteins and other factors related to energy homeostasis in rats (maintenance of the balance between supplied and dissipated energy) , inflammatory processes and metabolic diseases in male offspring and found alterations that can program susceptibility to diseases.
At the beginning of the experiment, the scientists induced both maternal and paternal obesity in rodents through a diet high in lipids and carbohydrates (containing lard and condensed milk). For males, hypercaloric food was provided during the ten weeks prior to mating and, for females, throughout pregnancy and lactation.
Then, the offspring was evaluated in two moments. In the first, blood and tissue analyzes were performed shortly after lactation (21 days of life). The tests were repeated at the beginning of adult life (90 days of life). We analyzed the expression of genes coding for proteins involved in the signaling pathway mediated by the TLR4 receptor (which acts on the activation of the innate immune response), factor ZO1 (related to intestinal permeability), orexigenic neuropeptides (appetite stimulants) and the leptin receptor (involved in the regulation of energy homeostasis).
The concentration of lipopolysaccharides (LPS) was also observed in the blood, molecules from the membrane of gram negative bacteria rich in endotoxins and which, when they escape from the intestine, trigger an inflammatory process; ghrelin, a hormone produced in the stomach and intestine, responsible for the feeling of hunger; of neuropeptide Y, involved in physiological processes in the central and peripheral nervous systems.
And the levels of certain bacteria in the intestinal microbiota, such as Bifidobacterium and Lactobacillus, were also evaluated.
“In cases of paternal diet rich in fats and sugars, we found important changes in the offspring soon after lactation, such as the increase in the serum concentration of lipopolysaccharides, which was positively associated with the activation of inflammatory pathways in the hypothalamus [região cerebral envolvida no controle do apetite]”, says Luciana Pellegrini Pisani, professor at the Department of Biosciences at Unifesp (Federal University of São Paulo), Baixada Santista campus, and study advisor.
“We also had a decrease in ZO1, which is associated with increased intestinal permeability, leading to greater translocation of lipopolysaccharides. [escape de LPS para fora do intestino]
In addition, in both moments, changes were found in factors associated with energy homeostasis. The researcher cites the increase in the inflammatory process, adiposity, in addition to weight gain associated with the increase in neuropeptide Y and the decrease in ghrelin and GLP1, a hormone in the gastrointestinal tract that acts in the regulation of appetite.
“The most interesting thing, however, was that in the 90-day-old offspring there was a change in adiposity and parameters of hunger and satiety control, regardless of the diet itself”, says Pisani. “That is, even with a balanced diet, we observed an increase in adiposity and changes in parameters related to energy homeostasis, and this increases the probability of developing metabolic diseases linked to obesity in adulthood.”
Maternal induced obesity resulted in increased neuropeptide Y and fecal reduction of Bifidobacterium and Lactobacillus in adult offspring.
The combined effect of parental hypercaloric diet showed an increase in neuropeptide Y at weaning and a lower content of Bifidobacterium and Lactobacillus in the adult offspring. These results led to the conclusion that the feeding of both parents can modulate the bacteria in the intestinal microbiota of the offspring and program their susceptibility to metabolic diseases.
Prospects
“Do these discoveries mean that, at birth, the offspring is already condemned to suffer metabolic problems? No, although there is a greater propensity, it is possible to reduce these deleterious effects with reprogramming through a change in lifestyle, that is, practice of physical activity, adequate food intake, balanced and without severe restrictions or drastic increases”, says Pisani.
“The study opens up the possibility that, from the moment there is a planning for pregnancy, there will also be a change in both the future mother's and the future father's lifestyle – which will make a big difference in the lives of children for generations .”
Still according to the researcher, the next steps are to expand the studies related to energy homeostasis and the intestine-brain action, analyzing other tissues and including female offspring, in which a different response has already been observed with regard to metabolic parameters associated with insulin resistance and the inflammatory process.