101. Leprdb/db Mice with Senescence Marker Protein-30 Knockout (Leprdb/dbSmp30Y/−) Exhibit Increases in Small Dense-LDL and Severe Fatty Liver Despite Being Fed a Standard Diet
- Author
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Naoto Nakamura, Goji Hasegawa, Hiroshi Okada, Jo Kitawaki, Naoki Maruyama, Michiaki Fukui, Morio Sawada, Takeshi Okanoue, Takafumi Senmaru, Akihito Ishigami, Yoshitaka Kondo, Akiko Amano, Hiroshi Obayashi, and Yuki Kishimoto
- Subjects
CD36 Antigens ,Male ,Animal Nutrition ,Mouse ,lcsh:Medicine ,Gene Expression ,Nonalcoholic Steatohepatitis ,Severity of Illness Index ,Biochemistry ,Pathogenesis ,Mice ,Oxidative Damage ,chemistry.chemical_compound ,Non-alcoholic Fatty Liver Disease ,Molecular Cell Biology ,Basic Cancer Research ,Nonalcoholic fatty liver disease ,lcsh:Science ,Receptor ,Animal Management ,Multidisciplinary ,Liver Diseases ,Fatty liver ,Intracellular Signaling Peptides and Proteins ,Agriculture ,Animal Models ,Endoplasmic Reticulum Stress ,Signaling Cascades ,Liver ,Oncology ,Receptors, Leptin ,Medicine ,Signal Transduction ,Research Article ,Senescence ,medicine.medical_specialty ,Clinical Research Design ,Lipoproteins ,Transgene ,Mice, Transgenic ,Gastroenterology and Hepatology ,Biology ,Diet, High-Fat ,Stress Signaling Cascade ,Molecular Genetics ,Model Organisms ,Internal medicine ,Genetics ,medicine ,Animals ,PPAR alpha ,Animal Models of Disease ,Nutrition ,Inflammation ,Cholesterol ,lcsh:R ,Calcium-Binding Proteins ,Cholesterol, HDL ,Immunity ,Proteins ,Computational Biology ,Cholesterol, LDL ,Lipid Metabolism ,medicine.disease ,Dietary Fats ,Metabolism ,Endocrinology ,Gene Expression Regulation ,Receptors, LDL ,chemistry ,Apoptosis ,lcsh:Q ,Clinical Immunology - Abstract
BACKGROUND/AIMS: The senescence marker protein-30 (SMP30) is a 34 kDa protein originally identified in rat liver that shows decreased levels with age. Several functional studies using SMP30 knockout (Smp30(Y/-) ) mice established that SMP30 functions as an antioxidant and protects against apoptosis. To address the potential role of SMP30 in nonalcoholic fatty liver disease (NAFLD) pathogenesis, we established Smp30(Y/-) mice on a Lepr(db/db) background (Lepr(db/db)Smp30(Y/-) mice). RESEARCH DESIGN/PRINCIPAL FINDINGS: Male Lepr(db/db)Smp30(Y/-) mice were fed a standard diet (340 kcal/100 g, fat 5.6%) for 16 weeks whereupon the lipid/lipoprotein profiles, hepatic expression of genes related to lipid metabolism and endoplasmic reticulum stress markers were analyzed by HPLC, quantitative RT-PCR and western blotting, respectively. Changes in the liver at a histological level were also investigated. The amount of SMP30 mRNA and protein in livers was decreased in Lepr(db/db)Smp30(Y/+) mice compared with Lepr(db/+)Smp30(Y/+) mice. Compared with Lepr(db/db)Smp30(Y/+) mice, 24 week old Lepr(db/db)Smp30(Y/-) mice showed: i) increased small dense LDL-cho and decreased HDL-cho levels; ii) fatty liver accompanied by numerous inflammatory cells and increased oxidative stress; iii) decreased mRNA expression of genes involved in fatty acid oxidation (PPARα) and lipoprotein uptake (LDLR and VLDLR) but increased CD36 levels; and iv) increased endoplasmic reticulum stress. CONCLUSION: Our data strongly suggest that SMP30 is closely associated with NAFLD pathogenesis, and might be a possible therapeutic target for NAFLD.
- Published
- 2013