Vitamin C (ascorbic acid) is an essential nutrient of most living tissues. We established a strain of Gulo-/- mice with known deficiency, in which vitamin C intake can be controlled by diet, like humans, and investigated the differen- tially expressed proteins following treatments with Helicobacter pylori and diethylnitrosamine (DENA) in the liver of Gulo-/- mice using a proteomic approach. Expression of p53, 14-3-3ε and 14-3-3δ in Gulo-/- mice liver tissue was analyzed by immunohistochemistry. 2-DE maps constructed from Gulo-/- mice liver and differentially expressed proteins in liver tissue were identified by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF/MS). In Gulo- /- mice after H. Pylori infection, followed by treatment with DENA, no differences in p53, 14-3-3ε and 14-3-3δ were observed by immunohistochemistry. Proteome analyses us- ing MALDI-TOF/MS resulted in successful identification of 12 proteins (nine proteins were up-regulated and three were down-regulated). Specifically, peroxiredoxin-6 and Alpha-1-antitrypsin 1-4 were up-regulated in liver after H. Pylori infection followed by treatment with DENA. These results indicated that oral supplementation with vitamin C led to rescue of Gulo-/- mice from vitamin deficiency, and protected the liver from H.pylori infection and/or DENA ef- fect, and vitamin C also protected the liver against oxidative stress.

Fraxinus rhynchophylla (Oleaceae), a deciduous tree, is known to have properties that include anti-inflammatory, convergence, febricide, antiblenophthalmia, antidiarrhea, antileukorrhea, and so forth. In addition, it has been used for traditional herbal medicine in East Asian countries, including Korea. In this study, we investigated the antioxidant and anti-inflammatory effects of Fraxinus rhynchophylla ethanol extract (FRE) in lipopolysaccharide (LPS)-induced murine macrophage Raw 264.7 cells with FRE pretreatment. We performed DPPH-assay, Western blot, and Reverse Transcription-Polymerase Chain Reaction (RT-PCR). FRE showed 85% free radical scavenging activity at concentrations of 80 µg/ml. Results of this study also showed that FRE down-regulates Cox-2 and iNOS expression in mRNA and protein level. In conclusion, crude ethanol extract of Fraxinus rhynchophylla exhibited antioxidant and anti-inflammatory activities, and it may potentially provide a valuable source of natural herbal agent to inhibit inflammation.