title: Time-course effect of high-glucose-induced reactive oxygen species on mitochondrial biogenesis and function in human renal mesangial cells.
abstract: The present study investigated the time-course effect of high-glucose-induced reactive oxygen species (ROS) on mitochondrial biogenesis and function in human renal mesangial cells and the effect of direct inhibition of ROS on mitochondria. The cells were cultured for 1, 4, and 7 days in normal glucose or high glucose in the presence and absence of Mn(III)tetrakis(4-benzoic acid)porphyrin chloride (MnTBAP) or catalase. Mitochondrial ROS production was assessed by confocal microscope. mtDNA copy number and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α), nuclear respiratory factors 1 (NRF-1), and mitochondrial transcription factor A (TFAM) transcripts were analyzed by real-time PCR. PGC-1α, NRF-1, and TFAM proteins were analyzed by Western blotting. Mitochondrial function was determined by assessing mitochondrial membrane potential and adenosine triphosphate (ATP) levels. High glucose induced significant increases in mitochondrial superoxide and hydrogen peroxide (H2 O2 ) at day 1, which remained significantly elevated at days 4 and 7. The copy number of mtDNA and expression of PGC-1α, NRF-1, and TFAM were significantly increased at 1 day in high glucose but were significantly decreased at 4 and 7 days. A progressive decrease in mitochondrial membrane potential was observed at 1, 4, and 7 days in high glucose, and this was associated with decreased ATP levels. Treatment of cells with MnTBAP or catalase during high-glucose incubation attenuated ROS production and reversed the alterations in mitochondrial biogenesis and function. Increased mitochondrial biogenesis in human renal mesangial cells may be an early adaptive response to high-glucose-induced ROS, and prolonged ROS production induced by chronic high glucose decreased mitochondrial biogenesis and impaired mitochondrial function. Protection of mitochondria from high-glucose-induced ROS may provide a potential approach to retard the development and progression of diabetic nephropathy.
authors.affiliation: Department of Molecular Medicine/Al-Jawhara Centre for Molecular Medicine, Genetics and Inherited Disorders, College of Medicine and Medical Sciences, Arabian Gulf University, Salmaniya Avenue, Road 2904, Building 293, Block 329, Manama, Kingdom of Bahrain.
authors.forename: Ghada
authors.initials: G
authors.lastname: Al-Kafaji
authors.affiliation: Department of Biochemistry, College of Medicine and Medical Sciences, Arabian Gulf University, Manama, Kingdom of Bahrain.
authors.forename: Mohamed Abdalla
authors.initials: MA
authors.lastname: Sabry
authors.affiliation: Department of Molecular Medicine/Al-Jawhara Centre for Molecular Medicine, Genetics and Inherited Disorders, College of Medicine and Medical Sciences, Arabian Gulf University, Salmaniya Avenue, Road 2904, Building 293, Block 329, Manama, Kingdom of Bahrain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Skrypnyk
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D002478:Cells, Cultured; D056915:DNA Copy Number Variations; D004272:DNA, Mitochondrial / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D005947:Glucose / Q000008:administration & dosage* / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial; D050527:Mesangial Cells / Q000166:cytology / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000378:metabolism; D001678:Organelle Biogenesis; D018384:Oxidative Stress / Q000502:physiology; D047495:PPAR gamma / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D013481:Superoxides / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D004272:DNA, Mitochondrial; D004268:DNA-Binding Proteins; D024101:Mitochondrial Proteins; D047495:PPAR gamma; D017382:Reactive Oxygen Species; D014157:Transcription Factors; C422562:mitochondrial transcription factor A; D013481:Superoxides; D000255:Adenosine Triphosphate; D006861:Hydrogen Peroxide; D005947:Glucose
keywords: catalase; diabetic nephropathy; high glucose; manganese superoxide dismutase; mitochondrial dysfunction; reactive oxygen species