The metabolomic characterization of changes in human milk metabolites under different storage temperature and time

The metabolomic profile of human milk is not well characterized compared with other biological fluids like blood, saliva or urine. To date there is no extensive study to determine the ―normal range‖ of the metabolite profile for human milk. In situations where infants are unable to breastfeed, expressed breastmilk is the recommended alternative. This is of significant importance for pre-term infants where breastmilk has been shown to increase their survival rate. Thus, optimal storage time and temperature are required to maintain the nutritional and functional benefits of expressed milk, while preventing the growth of pathogenic bacteria and break down of essential metabolites. Through gas chromatography coupled with mass spectrometry (GC -MS), our study aims to unravel the ―normal range of the metabolomic profile for human milk. To test the suitability of GC-MS for this study, a pilot study was undertaken to determine the milk metabolite profile under different storage temperatures over a 24-hour period. Milk expressed from 5 individual mothers, between 3 to 7 months post-partum was collected, aliquoted, then stored immediately either at room temperature, 4°C, -20°C and -80°C before processing for GC-MS analysis. Initial results shows metabolite levels were found to vary over time at higher in contrast to lower temperature stored milk samples. This variation over time could be either positive or negative depending on the metabolite. Variation in the metabolomic profile of the milk when stored at room temperature suggests metabolic modification of the metabolomic profile of the milk occurred presumably due of the cytosolic enzymes escaping into milk during the secretory process. This pilot study shows that milk needs to be stored at -20°C to retain its metabolomic profile

Proteomic Approaches for Studying the Phases of Wound Healing

© 2009, Springer Berlin Heidelberg. Proteome level information is necessary to understand the function of specific cell types and their roles in health and disease. Proteomics is a rapidly developing field with a wide range of applications in wound healing. The ability to use proteomics to assess the wound healing process would have many benefits, including earlier evidence of healing and better understanding of how different treatments affect the wound at the protein level. The basis of what is known about the chronic wound proteome is based on results from a broad collection of studies utilizing a number of different proteomic techniques on fluids and tissues from wounds with different etiologies. The identification of biomarkers associated with healing or delayed healing in chronic wounds could have great significance in the use of current treatments, as well as in the development of new therapeutic interventions