Immunoblotting membrane

Streptozotocin (STZ), NADH, NAD⁺, ATP, cytochrome c, antimycin A, sodium cyanide, decylubiquinol, n-dodecyl-beta-D-maltoside, sodium succinate, nitro blue tetrazolium (NBT) tablets, EDTA, dimethyl sulfoxide, dichlorophenolindophenol (DCPIP), NADPH, glucose-6-phosphate, and metformin hydrochloride were purchased form Sigma (St. Louis, MO). Lead nitrate, tricine, amino- N- caproic acid, Tris base, and Bis-tris were obtained from VWR International. Serva blue G-250 was purchased from Serva (Heidelberg, Germany). Coomassie brilliant blue G-250, SDS-PAGE protein standard markers, ECL Western blot detection kit, and immunoblotting membrane were purchased from Bio-Rad (Richmond, CA).

Biotin-linked aldehyde reactive probe ARP) for protein carbonyl assay was from Cayman Chemical (Ann Arbor, MI). Dihydrolipoamide was synthesized from lipoamide in our own laboratory using sodium borohydride as previously described [29] , [30] . ε-amino-N-caproic acid was obtained from MP Biochemicals. Acrylamide/bisacrylamide, ammonium persulfate, Bradford protein assay solution, coomassie brilliant blue (CBB) R-250, immunoblotting membrane, and an ECL immunochemical detection kit were from Bio-Rad laboratories (Richmond, CA, USA). NADH, BSA, lipoamide, EDTA, ATP, and NBT chloride tablets were obtained from Sigma (St. Louis, MO, USA). Serva Blue G was purchased from Serva (Heidelberg, Germany). Anti-PARP antibody was purchased from Trevigen (Gaithers burg, MD). Anti-NQO1 antibodies were from Sigma. Rabbit anti-DLDH polyclonal antibodies (IgG) and goat anti-rabbit IgG conjugated with horseradish peroxidase were purchased from US Biological (Swampscott, MA, USA) and Invitrogen (San Diego, CA, USA), respectively. Other antibodies were from Abcam (Cambridge, MA).