title: Curcumin Upregulates Antioxidant Defense, Lon Protease, and Heat-Shock Protein 70 Under Hyperglycemic Conditions in Human Hepatoma Cells.
abstract: Sirtuin 3 (SIRT3) regulates mitochondrial antioxidant (AO) defense and improves mitochondrial disorders. Curcumin protects mitochondria; however, the mechanisms need investigation. We postulated that curcumin increases AO defense under hyperglycemic conditions in HepG2 cells through SIRT3-mediated mechanisms. Cell viability was determined in HepG2 cells cultured with 5 mM glucose, 19.9 mM mannitol, vehicle control, 10 mM glucose, and 30 mM glucose in the absence or presence of curcumin for 24 h. SIRT3, nuclear factor-kappa B (NF-κB), heat-shock protein 70 (Hsp70), and Lon protein expressions were determined using western blot. Transcript levels of SIRT3, peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), cAMP response element-binding protein (CREB), glutathione peroxidase 1 (GPx1), and superoxide dismutase 2 (SOD2) were measured by quantitative polymerase chain reaction. Cell viability, SIRT3 protein expression, transcript levels of SIRT3, PGC-1α, CREB, GPx1, and SOD2 and protein expressions of NF-κB, Lon, and Hsp70 were significantly increased in the curcumin-treated hyperglycemic groups. Since curcumin and SIRT3 both improve mitochondrial function and AO defense, SIRT3 may be involved in the protective effects of curcumin.
authors.affiliation: Discipline of Medical Biochemistry, School of Laboratory Medicine and Medical Sciences, Howard College, University of KwaZulu-Natal , Durban, South Africa .
authors.forename: Shivona
authors.initials: S
authors.lastname: Gounden
authors.affiliation: Discipline of Medical Biochemistry, School of Laboratory Medicine and Medical Sciences, Howard College, University of KwaZulu-Natal , Durban, South Africa .
authors.forename: Anil
authors.initials: A
authors.lastname: Chuturgoon
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D006528:Carcinoma, Hepatocellular / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D003474:Curcumin / Q000494:pharmacology*; D005979:Glutathione Peroxidase / Q000235:genetics / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008113:Liver Neoplasms / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha / Q000235:genetics / Q000378:metabolism; D049070:Protease La / Q000235:genetics / Q000378:metabolism*; D056566:Sirtuin 3 / Q000235:genetics / Q000378:metabolism; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation; D000094765:Glutathione Peroxidase GPX1; D000099156:Superoxide Dismutase 2
chemical_list: D000975:Antioxidants; D003474:Curcumin; D005979:Glutathione Peroxidase; D018840:HSP70 Heat-Shock Proteins; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; D049070:Protease La; D056566:Sirtuin 3; D013482:Superoxide Dismutase; D000094765:Glutathione Peroxidase GPX1; D000099156:Superoxide Dismutase 2; C486497:PPARGC1A protein, human; C466093:SIRT3 protein, human; C000722067:GPX1 protein, human
keywords: Lon protease; SIRT3; curcumin; hyperglycemia; mitochondria