Repositori URV

Identifier: TDX:1004

Handle: https://hdl.handle.net/20.500.11797/TDX1004

Authors:
Beltrán Debón, Raúl

Abstract:
Obesity is perhaps the most common disease worldwide. The WHO qualify it as a pandemic disease. The excess of energy ingested is stored in adipose tissue, specifically designed to perform this function. But too much can be therefore, that adipose tissue is overwhelmed and must derive the excess of fat to other tissues such as liver, pancreas and muscle, which are not prepared for this purpose. The concomitant cellular stress generated, is accompanied by an altered metabolic and inflammatory response in multiple cell types. On the other hand, a moderate cell stress is normal, and does not have to be harmful. For example, exercise can cause a significant stress in some cell types, but not for that isunhealthy. Some molecules that can produce cellular stress, such as toxic, have similar behavior. Used at very low doses, can provide beneficial effects, it is what is known as hormesis. Plants synthesize different types of molecules to defend against the stress of drought or pests among other attacks. When humans eat plants, are able to benefit this stress experienced by plants by using the synthesized compounds. The idea that a specie will take advantage of the stress of another specie, is what the hypothesis of xenohormesistry to explain. Polyphenols are a class of hermetic compounds. In this Thesis we have developed analytical techniques for the characterization of the compounds present in aqueous extracts of plants and assessed the biological effects of consumption of polyphenol-rich aqueous extracts from Hibiscus sabdariffa and Aspalathuslinearis (rooibos).