Journal: Clinical and Translational Medicine
Article Title: Macrophage‐derived galectin‐3 contributes to pyroptosis, apoptosis and necroptosis through TLR4/MyD88/NF‐κB/NLRP3 during atherosclerosis
doi: 10.1002/ctm2.70637
Figure Lengend Snippet: Silencing galectin‐3 downregulated TLR4/MyD88/NF‐kB expression and attenuated ox‐LDL induced pyroptotic, apoptotic, and necroptotic cell death in macrophages. (A) Electron microscopy ultrastructural analysis of control and ox‐LDL‐induced macrophages. Control macrophages have a normal‐looking cellular structure, whereas ox‐LDL‐induced macrophages show loss of cell plasma integrity, chromatin condensation or fragmentation, and electron‐light zone. Scale bar: 2.5 µm. (B) Confocal microscopy with double immunofluorescence staining for caspase‐3 (red) and RIPK3 (green) in macrophages show the colocalisation of apoptotic and necroptotic components. Confocal microscopy analysis of double immunofluorescence labelling is indicative of overlapping expression of caspase‐3 (red) and GSDMD (green) in macrophages. Scale bar: 25 µm. (C) Representative Western blots and relative quantitative analysis of galectin‐3 in control macrophages and cells treated with ox‐LDL, ox‐LDL plus siControl RNA, and ox‐LDL plus siGalectin‐3 RNA. (D and E) Flow cytometry (E) and quantification analysis (F) with annexin V/PI double staining show that ox‐LDL increased the percentage of apoptotic cells in macrophages, which is alleviated by silencing galectin‐3. (F–H) Flow cytometry (F) and quantification analysis (G) with PI/Hoechst staining (H) show that ox‐LDL enhanced PI uptake in macrophages, which is markedly blocked by silencing galectin‐3. Scale bar: 50 µm. (I) Silencing galectin‐3 abrogated LDH release in macrophages ignited by ox‐LDL. (J) Ox‐LDL induced the accumulation of intracellular lipid droplets in macrophages, which are potently reversed by silencing galectin‐3. Scale bar: 50 µm. (K) Representative Western blots and relative quantitative analysis of NLRP3, GSDMD and GSDMD‐N in control macrophages and cells treated with ox‐LDL, ox‐LDL plus siControl RNA, and ox‐LDL plus siGalectin‐3 RNA. (L) Representative Western blots and relative quantitative analysis of caspase‐3, cleaved caspase‐3, caspase‐8 and cleaved caspase‐8 in control macrophages and cells treated with ox‐LDL, ox‐LDL plus siControl RNA, and ox‐LDL plus siGalectin‐3 RNA. (M and N) Representative Western blots and relative quantitative analysis of RIPK3, MLKL and phospho‐MLKL in control macrophages and cells treated with ox‐LDL, ox‐LDL plus siControl RNA, and ox‐LDL plus siGalectin‐3 RNA. (O) Ox‐LDL treatment promotes the release of proinflammatory cytokines (TNF‐1α, IL‐1β, IL‐18 and IL‐6) from macrophages, which is markedly rescued by silencing galectin‐3. (P and Q) Representative Western blots and relative quantitative analysis of TLR4, MyD88, NF‐kB and phospho‐NF‐kB in control macrophages and cells treated with ox‐LDL, ox‐LDL plus siControl RNA, and ox‐LDL plus siGalectin‐3 RNA. (R) Cell lysates from ox‐LDL‐treated macrophages are immunoprecipitated with anti‐TLR4 or anti‐MyD88 antibodies, and blotted with anti‐TLR4 or anti‐MyD88 antibodies. Data are derived from three to five independent experiments. * p ˂.05, ** p ˂.01, *** p ˂.001 by Student's t test. ns: not significant.
Article Snippet: Galectin‐3 deficiency suppressed pyroptosis, apoptosis and necroptosis in macrophages and migrated the progression of inflammation and atherosclerosis.
Techniques: Expressing, Electron Microscopy, Control, Clinical Proteomics, Confocal Microscopy, Double Immunofluorescence Staining, Immunofluorescence, Western Blot, Flow Cytometry, Double Staining, Staining, Immunoprecipitation, Derivative Assay