Protein network changes in different time points of human lactation

Introduction: Human milk is a rich source of bioactive proteins that supports the growth and immunological defences (1) of the newborn. There are several proteomic studies about human milk whey proteins(2j and fat globule proteins(3) during the lactation period , but at the moment there are no protein interaction data from all human milk proteins expressed in lactation period. In the present study we analyzed protein expression and the associated protein network at several time point in lactation period; i, 7, 15, 30 and 60 days from partum. Eighteen mothers for each time point with fixed criteria of recruitment were included in study. Methods: Samples were subjected to 1-DE and 2-DE and all proteins were separated from each experimental condition were identified by UPLC MS/MS. Biological networks were generated with STRING. Results: STRING analysis highlighted several GO-biological processes and GO-molecular functions mainly involved in defense response to bacteria and enzymatic activities. Classification of proteins and generation of biological networks were done . Conclusion: Present study provides the first evidence for protein network modulation in different stages of human lactation. Results indicated several possible biological processes and molecular functions modulated in each stage. Proteomic and bioinformatics investigations are necessary to well describe network role in modulation of nutraceutical and nutritional characteristics of human milk.