Influência da pasteurização em micro-vesículas de amostras de leite materno humano

Abstract

The present study aimed to analyze breast milk after pasteurization to check the effects of this process on the exosomes of human breast milk. Exosomes are nanovesicles from 30 to 100nm, containing miRNAs, that are present in biological fluids, like breast milk, which contains more of this particles. By breastfeeding the exosomes are transported to the body of the infant, donate their RNA to other cells and, thus, affect the production of protein of the receiving cell and provide immunological simulation and tolerance. This is a survey in which 8 samples were used from voluntary lactating, from 26 to 35 years old with babies from 3 weeks to 7 months. The samples were divided in two smaller with equal sizes, and one of them was subjected to pasteurization recommended by the Ministry of Health of Brazil (62.5 º C for 30 minutes). The methodology used for the purification of exosomes was dubble centrifugation, followed by filtration and ultracentrifugation and the quantification was done by qNano. For protein analysis was used Qubit for the quantifation and electrophoresis to process them in an acrylamide gel. From the results obtained in the quantification of exosomes by qNano, the pasteurized samples have larger amount of these particles, but the size range is smaller and more homogeneous. According to the quantification of protein, pasteurized samples also showed higher protein content, but in the resulting protein electrophoresis gel was observed bigger protein bands and traces of the same. This indicates that these samples have protein fragments. Thus, it is concluded that pasteurization causes the release of protein fragments and particles, interfering the results obtained on this study.