Pleiotropic Effects of Biguanides on Mitochondrial Reactive Oxygen Species Production

Figure 1

Characterization of brown adipose tissue (BAT) mitochondria. (a) SDS-PAGE and Western blot analysis of mitochondrial respiratory chain complexes in BAT and liver homogenates by polyclonal antibodies against mGPDH and VDAC and monoclonal antibodies against representative subunits of NDH (subunit NDUFA9), SDH (subunit SDHA), complex III (subunit UCQRC2), and actin. Two protein concentrations were loaded as indicated, representative image of three biological replicates. (b) Enzyme activities of mitochondrial dehydrogenases in mitochondria isolated from the BAT and liver. Activities were determined as rates of CoQ₁ reduction using respective substrates. Results are means ± SEM from three independent measurements. (c) Representative quality control curve of O₂ consumption and (d) representative trace of Δψ_m measurement in isolated BAT mitochondria. The following compounds were added: 10 mM glycerophosphate (GP), 0.3% BSA, 1 mM GDP, 1 mM ADP, 1 μM oligomycin (oligo), and 1 μM carbonyl cyanide-p-trifluoromethoxyphenylhydrazone (FCCP).

(a)

(b)

(c)

(d)