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bioRxiv · 10.1101/2021.02.19.431856

Messages From the Small Intestine Carried by Extracellular Vesicles in Prediabetes: a Proteomic Portrait

Ferreira, I.·de Oliveira, R. M.·Carvalho, A. S.·Beck, H. C.·Matthiesen, R.·Silva, B. C.·Macedo, M. P.
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Abstract

Extracellular vesicles (EVs) mediate communication in physiological and pathological conditions. In the pathogenesis of type 2 diabetes, inter-organ communication plays an important role in its progress and metabolic surgery leads to its remission. Moreover, gut dysbiosis is emerging as a diabetogenic factor. However, it remains unclear how gut senses metabolic alterations and whether this is transmitted to other tissues via EVs. Using a diet induced-prediabetic mouse model, we observed that protein packaging in gut derived EVs (GDE), specifically small intestine, is increased in prediabetes. Proteins related to lipid metabolism and to oxidative stress management were more abundant in prediabetic GDE compared to healthy controls. On the other hand, proteins related to glycolytic activity, as well as those responsible for the degradation of polyubiquitinated composites, were depleted in prediabetic GDE. Together, our findings show that protein packaging in GDE is markedly modified during prediabetes pathogenesis. Thus, suggesting that prediabetic alterations in small intestine are translated into modified GDE proteome, which are dispersed into the circulation where they can interact with and influence the metabolic status of other tissues. This study highlights the importance of the small intestine as a tissue that propagates prediabetic metabolic dysfunction throughout the body and the importance of GDE as the messenger.

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Ferreira, I., de Oliveira, R. M., Carvalho, A. S., Beck, H. C., Matthiesen, R., Silva, B. C., Macedo, M. P.. 2021-02-19. Messages From the Small Intestine Carried by Extracellular Vesicles in Prediabetes: a Proteomic Portrait. https://doi.org/10.1101/2021.02.19.431856

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