Proteome alterations of cortex and hippocampus tissues in mice subjected to vitamin A depletion

Vitamin A regulates the development and maintenance of the central nervous system. Studies of vitamin A depletion (VAD) and mutations of retinoid receptors in rodents have revealed a dysfunction of motor and cognitive abilities. However, the molecular mechanisms underlying these behavioral changes are not well understood. In this study, VAD mice were examined and abnormal motor behavior related to psychosis symptoms was found. With the use of two-dimensional gel electrophoresis (2-DE), two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) and mass spectrometric (MS) technologies, 44 and 23 altered protein spots were identified in the cortex and hippocampus, respectively, in VAD mice. By Western blot, the up-regulation of mitogen-activated protein kinase 1 (MAPK1) and proteasome subunit beta type 2 (PSMB2) in the cortex and that of dihydropyrimidinase-related protein 2 (DPYSL2) and PSMB2 in the hippocampus were observed in VAD mice. Bioinformatic analysis using DAVID revealed that altered proteins induced by VAD showed significant enrichment of (i) glycolysis, cytoskeleton, mitochondrion and glutamate metabolism in the cortex; and (ii) actin binding, dopamine receptor signaling and transmission of nerve impulse in the hippocampus. The up-regulations of DPYSL2, MAPK1 and PSMB2 may indicate the activated neuronal defensive mechanism in VAD brain regions, which may underlie the VAD-related psychosis behavior.