Journal: Alzheimer's & Dementia
Article Title: Endothelial NAD + depletion drives vascular senescence and neuroinflammation via mtDNA‐cGAS/STING‐CD38 signaling in Alzheimer's disease
doi: 10.1002/alz.71423
Figure Lengend Snippet: NAD + supplementation suppresses cGAS/STING pathway activation in cerebral endothelial cells of APP/PS1 mice. (A) Heatmap of differentially expressed key cGAS/STING pathway‐related genes (such as Cgas , Sting1 , Irf3 ) identified by RNA‐seq of cerebral vessel‐enriched fractions from APPtg and APPtg + NR mice ( n = 3 per group). (B, C) Representative western blot image (B) and densitometric quantification of cGAS, STING, phospho‐TBK1 Ser172 (p‐TBK1), and phospho‐IRF3 Ser396 (p‐IRF3) in cerebral vessel‐enriched fractions from APPwt, APPtg, and APPtg + NR mice (C; n = 6 per group). (D–G) Representative immunofluorescence images of hippocampus and cortex from APPtg and APPtg + NR mice showing CD31 (green) co‐stained with STING (D, red) or cGAS (F, red); quantification of STING (E) and cGAS (G) fluorescence intensity within CD31 + cerebral vessels were shown ( n = 5 or 6 mice per group); nuclei were counterstained with DAPI (blue). (H) qPCR analysis of SASP genes ( Il6 , Tnf , Il1b , Cxcl10 , Cxcl2 ) in cerebral vessel‐enriched fractions from APPtg and APPtg + NR mice ( n = 5 per group). (I) ELISA quantification of IL‐6, TNF‐α, and IL‐1β in the culture supernatants of bEnd.3 endothelial cells treated with vehicle control, NR, Aβ, or Aβ + NR ( n = 6 per group). (J) SA‐β‐galactosidase staining of bEnd.3 endothelial cells transfected with control siRNA (si‐Ctrl), Cgas siRNA (si‐ Cgas ), or Sting1 siRNA (si‐ Sting ) followed by Aβ stimulation or vehicle control; representative images show SA‐β‐gal + cells indicated by white arrows, with enlarged insets provided; the percentage of SA‐β‐gal + cells were quantified ( n = 5 per group). Data are presented as mean ± SEM. Statistical analyses were performed using one‐way ANOVA followed by Tukey's multiple comparisons test (C, E, G, I, J) or unpaired two‐tailed Student's t ‐test (H). p ‐values are indicated in the figure.
Article Snippet: For IL‐6 pathway analysis, BV‐2 microglia were incubated with 10 ng/ml anti‐mouse IL‐6 neutralizing antibody (α‐IL‐6; R&D systems, #MAB406) or anti‐mouse IL‐6Rα blocking antibody (α‐IL‐6R; R&D systems, #AF1830) in CM‐containing medium from bEnd.3 cultures.
Techniques: Activation Assay, RNA Sequencing, Western Blot, Immunofluorescence, Staining, Fluorescence, Enzyme-linked Immunosorbent Assay, Control, Transfection, Two Tailed Test