Sulforaphane Protects against High Cholesterol-Induced Mitochondrial Bioenergetics Impairments, Inflammation, and Oxidative Stress and Preserves Pancreatic β-Cells Function

Figure 1

SFN improves mitochondrial bioenergetics in Min6 cells exposed to cholesterol. Min6 cells were incubated with 320 µM of cholesterol and/or 2 or 10 µM of SFN or ES. Mitochondrial functions with SFN (a) or ES (b) treatment were measured in the form of OCR and expressed as nmol of oxygen consumed/min/mg of protein using the analyzer in cells treated for 6 h with vehicle (black solid circle) or with 320 µM cholesterol (chol) (red solid diamond), 2 µM SFN (green solid triangle), 10 µM SFN (blue solid square), 2 µM SFN + 320 µM chol (green vacant triangle), 10 µM SFN + 320 µM chol (blue vacant square), 2 µM ES (violet solid triangle), 10 µM ES (orange solid triangle), 2 µM ES + 320 µM chol (violet vacant triangle), and 10 µM ES + 320 µM chol (orange vacant triangle). (c) Basal respiration and (d) maximal respiration stimulated with 1.5 μM FCCP (State 3u) are shown. (e) ATP turnover was calculated as basal respiration minus respiration induced with 2 μM oligomycin (State 4o). (f) Coupling efficiency was calculated as the ratio of basal respiration minus State 4o relative to basal respiration. (g) Spare capacity was calculated as maximal respiration minus basal respiration. (h) Proton leak was calculated as State 4o minus nonmitochondrial OCR induced with 1 μM antimycin/rotenone. Control cells were not treated with cholesterol. All values are expressed as mean ± SEM, from three independent culture preparations, each treatment performed in quadruplicate. All two-ways ANOVAs and Bonferroni posttest. Values with different superscript letters indicate significant differences between groups. Chol: cholesterol; SFN: sulforaphane; ES: 3,4-dihydroxyphenylacetic acid; and OCR: oxygen consumption rate.

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