Integrated Proteomic Analysis Reveals a Substantial Enrichment of Protein Trafficking Processes in Hippocampus Tissue after Hypoxic Stress

Acute and chronic hypoxic episodes of the brain have been generally recognized as a common denominator of several neuropathologies of which cerebral ischemic stroke represents one of the leading causes of mortality and morbidity. In an attempt to clarify the plethora of molecular events elicited by ischemic or hypoxic stress, several studies have reported before on large-scale expression analysis; however, only a minority have put focus on proteome based changes. To further enrich our knowledge, we investigated the differences in protein levels following prolonged exposure of mice to global hypoxic stress in the hippocampus, one of the most susceptible regions of the brain. This was accomplished using the conventional 2-DE approach and peptide-centered quantitative methionyl-COFRADIC. Together both methods resulted in the identification of 110 unique hypoxia regulated proteins, and 34 posthypoxic reoxygenation regulated proteins based on 2-DE analysis alone. The integration and comparison of the implicated biological functions with other large-scale analyses of similar hypoxia and ischemic stroke models gave an overall resemblance of implicated biological processes apart from model specific alterations in distribution. Nevertheless, further examination of the data clearly depicted a substantial enrichment of protein trafficking and targeting processes in our data which could be related to synaptic plasticity and remodeling events.