Journal: Redox Biology
Article Title: Schaftoside improves HFpEF through regulation the autophagy-lysosome pathway by allosterically targeting CaMKII-δ
doi: 10.1016/j.redox.2024.103424
Figure Lengend Snippet: Schaftoside enhanced lysosome autophagy. (A) TEM images showed that SS promoted the formation of autolysosome in myocardial tissue. The down panels showed the enlarged images of selected areas defined by red boxes in the up panels. Yellow arrow: autolysosomes. Quantification of autolysosomes in TEM images (3–4 samples per group, n = 6 images). (B) Co-staining of heart sections with cTnl (red),Lamp1 antibody (green) and nuclei (DAPI, stain, blue) by immunofluorescence ( n = 6). (C) Lamp1, P62 and LC3 protein levels in myocardial tissue from mice of different groups tested by Western blot analysis ( n = 3). (D) TEM images showing that SS (80 ng/mL) promoted the formation of autophagosome in NMCM cells; The down panels show the enlarged images of selected areas defined by red boxes in the left panels. Yellow arrow: lysosomes. Quantification of autolysosomes in TEM images (3 samples per group, n = 5 images). (E) Immunofluorescence images showed that SS improved lysosomal function inhibited by AngII in NMCM cells. Lamp1 antibodies (green) and nucleus (DAPI, blue) ( n = 3). (F) Lamp1 protein levels in NMCM cells from SS tested by Western blot analysis ( n = 4). (G, H) Determination of lysosomal pH in cardiomyocytes using the ratiometric dye LysoSensor Yellow/Blue DND-160, followed by quantification of fluorescence signals. Acidic organelles predominantly exhibit yellow fluorescence (pH∼4.5), while less acidic organelles display more blue fluorescence (pH∼6) ( n = 3). (I, J) Cells were transfected with mRFP-GFP-LC3 adenovirus for 48 h. Autophagosomes are expressed as yellow puncta, and autolysosomes are expressed as red puncta ( n = 4); Scale bar = 50 μm. (K) Baf-A1 (100 nM), which disrupted autophagosome-lysosome fusion and the acidification of autolysosomes, inhibited the reduction of LC3II levels triggered by SS in cardiomyocytes. All graphs show mean ± SEM. Statistical analysis was performed using ordinary-one way ANOVA. ∗ P < 0.05, ∗∗ P < 0.01, ∗∗∗ P < 0.001, ∗∗∗∗ P < 0.0001. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)
Article Snippet: Next, the membranes were blocked with 5 % skimmed milk for 1 h. They were probed with primary antibodies against CaMKII-δ, p -CaMKII-δ and Lamp1 (Invitrogen, CA, USA), P62 and LC3 (CST, MA, USA), AKT and p -AKT (Abclonal, Wuhan, China), diluted at 1:1000 in primary antibody dilution buffer at 4 °C overnight.
Techniques: Staining, Immunofluorescence, Western Blot, Fluorescence, Transfection