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bioRxiv · 10.1101/2021.09.10.459820

High-fat diet feeding reduces the expression of Rab3a, Rab3gap1, and Rab3Gap2 genes that are pivotal to neuronal exocytosis.

Ferrreira, L. A.·Martins, F. V.·Freitas, M. L.·Oliveira, L. R.·Castro Junior, C. J.·Jehee, F. S.·Bosco, A. A.·Fernandes, K. S.
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Abstract

The Rab3A and Rab3gaps are essential to the Ca+2-dependent neuronal exocytosis in the hypothalamus. The arcuate nucleus of the hypothalamus (ARC) controls food intake and energy expenditure. We have earlier described that the high-fat diet (HFD) feeding induces an obesity phenotype with high leptin production and alteration of proteins related to endosome sorting, and ubiquitination in the ARC of mice. In this study, real-time PCR data analysis revealed that HFD feeding decreases significantly Rab3a, Rab3gap1, and Rab3gap2 transcript levels in the ARC when compared to the group receiving a control diet. The decrease of Rab3gap1/2 transcript levels in the ARC was strongly associated with an increase in plasma leptin. Altogether, our studies demonstrate that HFD feeding could be altering the general network of endosome compartmentalization in the ARC of mice, contributing to a failure in exocytosis and receptor recycling. Graphical abstract O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

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Ferrreira, L. A., Martins, F. V., Freitas, M. L., Oliveira, L. R., Castro Junior, C. J., Jehee, F. S., Bosco, A. A., Fernandes, K. S.. 2021-09-11. High-fat diet feeding reduces the expression of Rab3a, Rab3gap1, and Rab3Gap2 genes that are pivotal to neuronal exocytosis.. https://doi.org/10.1101/2021.09.10.459820

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