Fig. 6: Overexpression of Nqo1 enhances mitochondrial biogenesis in vitro and in vivo.

a mRNA level of Park2 and Nqo1 in eWAT of WT and Ob/+ mice (n = 6 mice for each group, except one sample in Ob/+ group with undetectable Nqo1 gene expression) [Unpaired Student’s t test two-tailed. For Nqo1 WT vs. Ob/+, p = 0.0276, 95%CI = −0.1921 to 2.596, R squared = 0.4334]. b western blot analysis of Nqo1 in eWAT of WT and Ob/+ mice (n = 6 mice for each group). c Oil Red O staining and the quantification of Oil Red O in differentiated 3T3-L1 Control (Scr) and Nqo1^OE adipocytes (n = 9 biological replicate, scale bars = 200 μm) [Unpaired Student’s t test two-tailed. p < 0.0001, 95%CI = −0.3572 to −0.2469, R squared = 0.8939]. d mRNA level of mitochondrial and related genes in the differentiated 3T3-L1 Control (Scr) and Nqo1^OE adipocytes (n = 3 biological replicate) [Unpaired Student’s t test two-tailed. For Pgc1α, p = 0.0030, 95%CI = 1.988–5.001, R squared = 0.9120; for mtNd1, p = 0.0333, 95%CI = 00.09336–1.359, R squared = 0.7175; for mtNd4 p = 0.0341, 95%CI = 0.06033–0.9301, R squared = 0.7142; for mtNd4l, p = 0.0362, 95%CI = 0.05190–0.9380, R squared = 0.7063]. e Western blot and densitometry analysis of Pgc1α and OXPHOS proteins (normalized to Hsp90 or GAPDH) in the differentiated 3T3-L1 Control (Scr) and Nqo1^OE adipocytes (n = 3 biological replicate) [Unpaired Student’s t test two-tailed. For Pgc1α, p = 0.0475, 95%CI = 0.01028–1.129, R squared = 0.6665; for mtCo1, p = 0.0120, 95%CI = 0.1436–0.6442, R squared = 0.8267]. f mtDNA content of the differentiated 3T3-L1 Control (Scr) and Nqo1^OE adipocytes (n = 3 biological replicate) [Unpaired Student’s t test two-tailed. p = 0.0108, 95%CI = 0.2180–0.9195, R squared = 0.8351]. g Mitochondrial oxygen consumption rate of the differentiated 3T3-L1 Control (Scr) and Nqo1^OE adipocytes (n = 5 biological replicate). [Unpaired Student’s t test two-tailed. For 31 min Control (Scr) vs. Nqo1^OE, p = 0.0278, 95%CI = 00.7418–9.814, R squared = 0.4737; For 43 min Control (Scr) vs. Nqo1^OE, p = 0.0200, 95%CI = 1.247–10.99, R squared = 0.5119]. h Experimental design for AAV8 injection in HFD-fed male WT mice. Created with BioRender.com. i Western blot and densitometry analysis of Nqo1 and Pgc1α proteins (normalized to Actin) in eWAT of AAV8-Control or AAV8-Nqo1 injected mice (n = 7 mice per group) [Paired Student’s t test two-tailed, t = 3.058. For Nqo1, p = 0.0223, 95%CI = 0.1673–1.508, R squared = 0.6091]. j H&E-stained sections of the eWAT from AAV8-Control or AAV8-Nqo1 injected mice; scale bars = 50 μm; The dot graph on the right is the quantified adipocyte area from H&E-stained sections of the eWAT from HFD-fed Control f/f and Parkin^Adi mice (n = 6 mice for AAV8-Control group, n = 7 for AAV8-Nqo1 group, total1603-1932 adipocytes) [Unpaired Student’s t test two-tailed. p = 0.0296, 95%CI = −9156 to −476.6, R squared = 0.001345]. k Western blot and densitometry analysis of OXPHOS protein levels (normalized to Hsp90) in eWAT of AAV-Control or AAV8-Nqo1 injected mice (n = 5 mice per group) [Paired Student’s t test two-tailed. For Sdhb, t = 3.916, p = 0.0173, 95%CI = 0.1716–1.008, R squared = 0.7931; for Ndufb8, t = 2.886, p = 0.0447, 95%CI = 0.03842–1.988, R squared = 0.6755]. l mtDNA content of the eWAT from AAV8-Control or AAV8-Nqo1 injected mice (n = 5 mice per group) [Paired Student’s t test two-tailed. t = 4.023, p = 0.0158, 95%CI = 0.1896–1.034, R squared = 0.8018]. m Heatmap of mtDNA encoded genes from RNA sequencing results in AAV8-Control or AAV8-Nqo1 injected eWAT (n = 3 mice per group). Data are presented as mean ± SEM. AU = arbitrary units. Oligo = oligomycin, FCCP = trifluoromethoxy carbonylcyanide phenylhydrazone, R/A = rotenone/antimycin a. * p < 0.05, *** p < 0.001. Source data are provided as a Source Data file.