Pregnancy, extra virgin olive oil and low birth weight fetuses

In a recent study, the effects caused by maternal intake of an antioxidant substance present in virgin olive oil on the hippocampus of fetal pigs with weight values ​​below normal have been analyzed and compared.

The research team, made up of experts from the Zaidín Experimental Station, a center of the Higher Council for Scientific Research (CSIC) in Granada, in collaboration with the Comparative Physiology Laboratory of the National Institute for Agricultural and Food Research and Technology (INIA) of the CSIC, the Department of Biochemistry and Molecular Biology of the Autonomous University of Barcelona (UAB) and the Department of Animal Production and Health of the Cardenal Herrera University, in Spain, has demonstrated the neuroprotective effects of a natural antioxidant substance abundant in the oil. of virgin olive in low weight porcine fetuses.

Specifically, this scientific team has observed that supplementing the maternal diet with said substance during the last two thirds of pregnancy improves the brain development of fetuses affected by retarded intrauterine growth; that is, they present weight values ​​below normal.

Previous studies carried out by this same group of experts showed the effectiveness of this substance as a neuronal protector in different parts of the brain. Specifically, researchers have been able to observe that it acts on the hippocampus, an area involved in memory, learning, moods, stress and cognition. It also affects the amygdala, an almond-shaped area responsible for processing and storing emotional reactions, essential for survival; and in the prefrontal cut, linked to executive functions such as planning or memory.

Called hydroxytyrosol, this natural antioxidant is found in its pure state in the form of a transparent and odorless liquid in the olive tree, mainly in olives. This substance is one of the most abundant compounds in extra virgin olive oil and is responsible for giving this food its bitter taste. However, it is not found in the rest of the oils because it is removed with refining.

In the new study, the research team has deepened the knowledge of the effect of hydroxytyrosol on the set of proteins that are translated in the hippocampus of fetuses affected by retarded intrauterine growth. “With this study, we seek to identify the molecular mechanisms that modulate the neuroprotective effects of this substance at the brain level,” explains researcher Consolación García-Contreras, from the Zaidín Experimental Station, to the Discover Foundation.

Consolation Garcia-Contreras. (Photo: Discover Foundation)

To do this, they carried out a proteomic study, that is, they determined and quantified all the proteins that were being translated in this area of ​​the brain in fetuses whose mothers had been supplemented with hydroxytyrosol and in fetuses whose mothers had not received the supplement.

The objective of this comparison was focused on evaluating possible changes in terms of abundance. “We identified almost 6,000 proteins, a complete map that we were breaking down with a very restrictive statistical program to check which of them appeared differentially expressed in the two groups studied,” explains García-Contreras.

The results obtained showed that the consumption of hydroxytyrosol barely influenced the amount of proteins that were being produced in the hippocampus between the fetuses of untreated mothers and the fetuses from mothers who received a supplement of this compound in their diet. “The consumption of this molecule prevents oxidative processes at the neuronal level, but not through changes in protein levels”, clarifies the author of the study.

However, they observed differences in abundance of 11 proteins between both groups. Of all of them, three proteins with neuroprotective functions were more abundant in the group of treated fetuses.

One of them acts as a messenger of brain signals. “This protein prevents the incorporation of toxic metabolites into the nervous system. Its absence is related to the loss of cognitive function and aging”, points out García-Contreras.

Another of the most abundant proteins repairs abnormal structures that prevent other peptides from joining the protein chain and performing their function. “In fetuses whose mothers took hydroxytyrosol, there were more of these proteins. The lack of them or a low availability of them causes this cycle to break and as a consequence different diseases related to a protein malformation can arise ”, points out the expert.

The third of these proteins is related to cognitive function. “If their presence is low, there are more chances of suffering from stress and anxiety,” says García-Contreras.

To obtain these conclusions, the experts carried out an experimental design in which two groups were included: on the one hand, a group of Iberian sows that were given the hydroxytyrosol supplement during the last two thirds of gestation, and a group ( “control”) which was not included.

Feeding was restricted to 50% of their daily needs in both groups to ensure the appearance of fetuses with retarded intrauterine growth and, thus, to be able to verify the effectiveness or otherwise of hydroxytyrosol.

Retarded intrauterine growth is mainly caused by a deficit in the supply of nutrients and/or oxygen to the fetus due to inadequate maternal nutrition (excess or deficiency), or by placental insufficiency unrelated to maternal nutrition.

With this model of feeding in pregnant sows, the experts ensured the appearance of fetuses affected by retarded intrauterine growth characterized, among many other disorders, by presenting inadequate brain development. “If we transfer it to human medicine, these fetuses will give rise to babies with a low birth weight, a disorder associated with a higher incidence of neonatal mortality and morbidity, as well as a greater propensity to suffer from metabolic and cardiovascular diseases in adult life,” he adds. the expert.

The study is titled “Polyphenols and IUGR Pregnancies: Effects of the Antioxidant Hydroxytyrosol on the Hippocampus Proteome in a Porcine Model. And it has been published in the academic journal Antioxidants. (Source: Discover Foundation)