Impact of Seasonal rhythms on gut microbiota: influence on proanthocyanidins functionality in obesity

Identifier:  TDX:3935

Handle: https://hdl.handle.net/20.500.11797/TDX3935

Authors:  Arreaza Gil, Verónica

Abstract:
Biological rhythms are crucial to adjust the physiological and metabolic processes of the organism to the time of day (circadian rhythms) or year (seasonal rhythms). This synchronization is orchestrated by external signals (Zeitgeber), being the light the most important one. In this context, the gut microbiota, which plays an important role to maintaining the homeostasis of the organism, can be modulated by changes in the light length of the day (photoperiod). This fact is of great relevance due to the gut microbiota is involved in the metabolism of bioactive compounds, such as proanthocyanidins (PAs), which are the most abundant polyphenols in western diet. In fact, these compounds have shown beneficial effects on metabolic disorders such as obesity. Therefore, the functionality of these PAs could be influenced by the time of the year or even the day in which they are administered. Hence, this thesis aims to study the relationship between seasonal rhythms, which have been less studied than circadian rhythms, gut microbiota, and their impact on the functionality of PAs in obesity. To do this, we studied the influence of seasonal rhythms on gut microbiota composition and other physiological parameters in healthy and cafeteria-induced obese Fischer 344 rats, and evaluated the effect of PAs administration in different conditions of gut microbiota dysbiosis. The results showed that seasonal rhythms alter the composition of the gut microbiota, which was associated with changes in weight, glucose tolerance, and levels of oxylipins (inflammatory mediators).