title: SJSZ glycoprotein (38 kDa) inhibits cell cycle and oxidative stress in N-methyl-N'-nitro-N-nitrosoguanidine-induced ICR mice.
abstract: The initiation stage of liver cancer is closely related to abnormal cell proliferation as observed for other types of carcinogenesis. Recently, we isolated a glycoprotein from Styrax japonica Siebold et al Zuccarini (SJSZ glycoprotein), which consists of a carbohydrate moiety (52.64%) and a protein moiety (47.36%). In this study, the antitumoric mechanism of SJSZ glycoprotein during the initiation stage in N-Methyl-N`-nitro-N-nitrosoguanidine (MNNG; 40 mg/kg, BW)-induced ICR was investigated. First, we evaluated the activities of lactate dehydrogenase (LDH), alanine aminotransferase (ALT), thiobarbituric acid-reactive substances (TBARS), and activities of antioxidative enzymes [superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT)] in mouse liver tissue and serum. The alpha-fetoprotein (AFP), cell cycle-related factors [cyclin D1/ cyclin dependent kinase (CDK) 4], cell cycle inhibitors (CKIs; p53, p21, and p27), and proliferating cell nuclear antigen (PCNA) were then assessed using Western Blot analysis. The results of this analysis showed that the SJSZ glycoprotein (10 mg/kg, BW) decreased the levels of LDH, ALT, TBARS, and the expression of AFP but it increased the activity of hepatic anti-oxidant enzymes (SOD, GPx and CAT). In addition, the SJSZ glycoprotein (10 mg/kg, BW)was shown to decrease the expression of cyclin D1/CDK4 and PCNA and increase the expression of CKIs (p53, p21, and p27). The results in this study indicate that the SJSZ glycoprotein displays anti-oxidative stress and anti-cell proliferation activity in MNNG induced ICR.
authors.affiliation: Molecular Biochemistry Laboratory, Biotechnology Research Institute & Center for the Control of Animal Hazards Using Biotechnology (BK21), Chonnam National University, Gwang-ju, South Korea.
authors.forename: Jin
authors.initials: J
authors.lastname: Lee
authors.forename: Kye-Taek
authors.initials: KT
authors.lastname: Lim
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005978:Glutathione / Q000378:metabolism; D006023:Glycoproteins / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D008297:Male; D008769:Methylnitronitrosoguanidine / Q000494:pharmacology; D051379:Mice; D008813:Mice, Inbred ICR; D018384:Oxidative Stress / Q000187:drug effects*; D010940:Plant Proteins / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D013329:Structure-Activity Relationship; D032362:Styrax / Q000737:chemistry
chemical_list: D000975:Antioxidants; D006023:Glycoproteins; D010940:Plant Proteins; D018809:Proliferating Cell Nuclear Antigen; D008769:Methylnitronitrosoguanidine; D005978:Glutathione