Journal: Nature Communications
Article Title: PRDX1 promotes testosterone synthesis and attenuates aging via redox regulation of ATG4B to modulate lipophagy
doi: 10.1038/s41467-025-65328-4
Figure Lengend Snippet: a WB analyses of autophagy-related proteins in negative control (NC) and PRDX1 knockdown (KD) TM3 cells. The relative levels of LC3 and p62 were showed. b WB analyses of LC3 and p62 levels in cells after indicated treatments for 8 h. The relative levels of LC3 and p62 were showed. 3-MA (3-methyladenine, 10 mM), CQ (chloroquine, 20 μM), PA (pepstatin A,10 μg/mL), LP (leupeptin, 100 μM), Rapa (rapamycin, 10 nM). c WB analyses of LC3 and p62 levels in cells after treatment with gradient H O for 1 h. The relative levels of LC3 and p62 were showed. d – f Co-immunofluorescence of LC3 (green) and LAMP1 (red), a lysosome marker, in cells with or without H O treatment (100 μM, 1 h). Nuclei were stained with DAPI (blue). Relative intensity within the indicated area outlined in ( d ) was measured and the values indicate percentages of colocalizing signals ( e ). A.U., arbitrary units. Pearson’s colocalization coefficients were determined ( f ). n = 5 for each group. g , h LC3-GFP-RFP dual-fluorescence assay showing autophagic flux. Cells were transfected with lentivirus harboring LC3-GFP-RFP. The ratio of RFP + GFP + (presents autophagysome) to RFP + GFP - (presents autolysosome) was calculated and showed in ( h ). n = 5 for each group. i , j Proteinase K and Triton X-100 assay to examine the integrity of autophagosome membrane. Quantification of p62 level was showed in ( j ). n = 5 for each group. k – m Co-fluorescence of BODIPY 493/503 (green) and LC3 (red). Relative intensity within the indicated area outlined in ( k ) was measured and the values indicate percentages of overlapping signals ( l ). A.U., arbitrary units. Pearson’s colocalization coefficients were determined ( m ). n = 5 for each group. n – p Co-fluorescence of BODIPY 493/503 (green) and LysoTracker (red). Relative intensity within the indicated area outlined in ( n ) was measured and the values indicate percentages of colocalizing signals ( o ). A.U. arbitrary units. Pearson’s colocalization coefficients were determined ( p ). n = 5 for each group. q , r Lipoprotein uptake and degradation assay. Dil-HDL was added into media for 2 h and then withdrew for 8 h. Live-cell images were captured at indicated time-points. Average Dil-HDL intensity (red) per cell was measured and the curves were showed in ( r ). n = 5 for each group. s Time-lapse imaging of contacts between lipoproteins (Dil-HDL, red) and autophagic vacuoles (LC3, green). In NC group, lipoproteins were quickly degraded (white arrowheads), while in KD group, they kept steady (blue arrowheads). See Supplementary Movies and . t Time-lapse imaging of contacts between autophagic vacuoles (LC3, green) and lysosome (LysoTracker, red). In NC cells, LC3 puncta frequently contacted with lysosomes and then disappeared (gray arrowheads), with new LC3 puncta approaching lysosomes (cyan arrowheads). While in KD cells, a majority of LC3 puncta did not associated with lysosomes and remained visible (pink arrowheads), and even those having contacts with lysosomes kept visible (yellow arrowheads). See Supplementary Movies and . n = 50 cells examined over 5 independent experiments. *** P < 0.001. n.s. not significant. All values represent Mean ± SEM. Data in ( h ) were analyzed by chi-square test, those in ( m ) and ( p ) were analyzed by t -test, and others by two-way ANOVA followed by the Dunnett test for between-group differences. Scale bars = 5 μm in ( d ), ( k ) and ( n ), 100 μm in ( g ), 10 μm in ( q ), 1 μm in ( s ) and ( t ).
Article Snippet: The aged Ctrl and Prdx1 -cKO mice (19 months old) were intraperitoneally injected with ebselen (20 mg/kg/day; HY-13750, MedChemExpress, Elizabeth, NJ, USA.) once daily for 1 month.
Techniques: Negative Control, Knockdown, Immunofluorescence, Marker, Staining, Fluorescence, Transfection, Membrane, Degradation Assay, Imaging