Intracellular GSH regulates the ability of cells to undergo apoptosis

that a subgroup of AD LCLs will demonstrate abnormal reserve capacity when exposed to increasing concentrations of ROS. We further hypothesized that this subgroup of AD LCLs will be more vulnerable to ROS and will exhibit an increase in intracellular and intramitochondrial mechanisms to compensate for increased ROS. To this end we measured glycolysis as representative of intracellular compensatory mechanisms and cellular UCP2 content and function as a representation of intramitochondrial compensatory mechanisms. For the first time, we demonstrate atypical changes in mitochondrial respiration when exposed to ROS in a subgroup of AD LCLs, and that this atypical AD subgroup exhibits higher UCP2 content. Methods Lymphoblastoid Cell Lines and Culture Conditions Twenty five LCLs derived from white males diagnosed with AD chosen from pedigrees with at least 1 affected male sibling were obtained from the Autism Genetic Resource Exchange or the National Institutes of Mental Health center for collaborative genomic studies on mental disorders. Thirteen age-matched control LCLs derived from healthy 6099352 white male donors with no documented behavioral or neurological disorder or first-degree relative with a medical disorder that could involve abnormal mitochondrial function were obtained from Coriell Cell Repository. Due to low availability of control LCLs from children with no documented neurological disorders, we paired a single control LCL line with 1, 2 or, in one case, 3 AD LCL lines. On average, cells were studied at passage 12, with a maximum passage 23428871 of 15. Genomic stability is very high at this low passage number. Cells were maintained in RPMI 1640 culture medium with 15% FBS and 1% penicillin/streptomycin in a humidified incubator at 37uC with 5% CO2. Seahorse Assay We used the state-of-the-art Seahorse Extracellular Flux 96 Analyzer, to measure the oxygen consumption rate, an indicator of mitochondrial respiration, and the extracellular acidification rate, an indicator of glycolysis, in real-time in live intact LCLs. Inhibition of UCP2 To determine the effects of UCP2 inhibition on mitochondrial respiration in the AD LCLs, we treated the LCLs with genipin, an extract from Gardenai jasminoides, and a known UCP2 inhibitor. For these experiments, LCLs were cultured with 50 mM SNDX-275 web genipin for 24 h prior to the Seahorse assay. Titrations were performed to determine the optimal dose of genipin to alter proton leak respiration without significantly affecting cell viability. 11 mM glucose, 2 mM L-glutamax, and 1 mM sodium pyruvate). Cells were plated with at least 4 replicate wells for each treatment group. Titrations were performed to determine the optimal concentrations of oligomycin, FCCP, antimycin A and rotenone. Immunoblot Analysis LCLs were lysed using RIPA lysis buffer containing 1% NP40, 0.1% SDS, 1% PMSF, 1% protease inhibitor cocktail and 1% sodium orthovanadate. Protein concentration was determined using a BCA Protein Assay Kit, and lysates were prepared with 4X Laemmli Sample Buffer and 5% beta-mercaptoethanol. Samples were boiled for 5 min and cooled on ice for 5 min, and 50 mg of protein per lane was electrophoresed on a 10% polyacrylamide gel and transferred to a 0.45 mM PVDF membrane. Transfer efficiency was tested by Ponceau S staining of gels. Membranes were probed overnight at 4uC with goat anti-UCP2 after blocking with 2% non-fat milk. For detection, the membranes were incubated with donkey anti-goat-HRP and the blots were Redox Challethat a subgroup of AD LCLs will demonstrate abnormal reserve capacity when exposed to increasing concentrations of ROS. We further hypothesized that this subgroup of AD LCLs will be more vulnerable to ROS and will exhibit an increase in intracellular and intramitochondrial mechanisms to compensate for increased ROS. To this end we measured glycolysis as representative of intracellular compensatory mechanisms and cellular UCP2 content and function as a representation of intramitochondrial compensatory mechanisms. For the first time, we demonstrate atypical changes in mitochondrial respiration when exposed to ROS in a subgroup of AD LCLs, and that this atypical AD subgroup exhibits higher UCP2 content. Methods Lymphoblastoid Cell Lines and Culture Conditions Twenty five LCLs derived from white males diagnosed with AD chosen from pedigrees with at least 1 affected male sibling were obtained from the Autism Genetic Resource Exchange or the National Institutes of Mental Health center for collaborative genomic studies on mental disorders. Thirteen age-matched control LCLs derived from healthy white male donors with no documented behavioral or neurological disorder or first-degree relative with a medical disorder that could involve abnormal mitochondrial function were obtained from Coriell Cell Repository. Due to low availability of control LCLs from children with no documented neurological disorders, we paired a single control LCL line with 1, 2 or, in one case, 3 AD LCL lines. On average, cells were studied at 7190624 passage 12, with a maximum passage of 15. Genomic stability is very high at this low passage number. Cells were maintained in RPMI 1640 culture medium with 15% FBS and 1% penicillin/streptomycin in a humidified incubator at 37uC with 5% CO2. Seahorse Assay We used the state-of-the-art Seahorse Extracellular Flux 96 Analyzer, to measure the oxygen consumption rate, an indicator of mitochondrial respiration, and the extracellular acidification rate, an indicator of glycolysis, in real-time in live intact LCLs. Inhibition of UCP2 To determine the effects of UCP2 inhibition on mitochondrial respiration in the AD LCLs, we treated the LCLs with genipin, an extract from Gardenai jasminoides, and a known UCP2 inhibitor. For these experiments, LCLs were cultured with 50 mM genipin for 24 h prior to the Seahorse assay. Titrations were performed to determine the optimal dose of genipin to alter proton leak respiration without significantly affecting cell viability. 11 mM glucose, 2 mM L-glutamax, and 1 mM sodium pyruvate). Cells were plated with at least 4 replicate wells for each treatment group. Titrations were performed to determine the optimal concentrations of oligomycin, FCCP, antimycin A and rotenone. Immunoblot Analysis LCLs were lysed using RIPA lysis buffer containing 1% NP40, 0.1% SDS, 1% PMSF, 1% protease inhibitor cocktail and 1% sodium orthovanadate. Protein concentration was determined using a BCA Protein Assay Kit, and lysates were prepared with 4X Laemmli Sample Buffer and 5% beta-mercaptoethanol. Samples were boiled for 5 min and cooled on ice for 5 min, and 50 mg of protein per lane was electrophoresed on a 10% polyacrylamide gel and transferred to a 0.45 1417961 mM PVDF membrane. Transfer efficiency was tested by Ponceau S staining of gels. Membranes were probed overnight at 4uC with goat anti-UCP2 after blocking with 2% non-fat milk. For detection, the membranes were incubated with donkey anti-goat-HRP and the blots were Redox Challe

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