Polyphenol-rich foods: study unveils new function in the brain

26-Jul-2024

A team of scientists from the Molecular Nutrition and Health group at NOVA Medical School discovered that a group of polyphenol metabolites derived from our diet (i.e. fruits like berries) not only can reach the brain but also improve the blood-brain barrier properties. These findings show that we are another step closer to understanding the molecular mechanisms behind the benefits of polyphenol-rich foods to brain health.

In previous studies, the NOVA Medical School research group found, in humans, the same group of polyphenol metabolites as abundant in the bloodstream after the intake of a polyphenol-rich meal (i.e. berry mixture puree). Moreover, using simple cell models (namely neurons and microglia cells), they discovered that these metabolites hold strong neuroprotective and anti-inflammatory effects, as well as some hints regarding their capacity to cross the blood-brain barrier and reach the brain. However, their true in vitro and in vivo brain accessibility remained to be unveiled.

The study now published at the scientific journal Food and Function and led by Inês Figueira, post-doc researcher, showed that polyphenol metabolites are in fact brain accessible, a phenomenon which happens almost immediately and during relatively short periods of time (within second to minutes time window), both using cell models of the barrier and upon injection in rats. Surprisingly, the team also found these compounds can improve the barrier properties and tightness, an essential feature to prevent harmful substances from entering the brain.

Although further work is still needed, these discoveries may help to develop preventive or even therapeutic applications in the scope of neurodegenerative diseases like Parkinson and Alzheimer, namely in prevention or in the initial stages of disease progression.