Journal: Frontiers in Immunology
Article Title: GDF15 orchestrates mitochondrial-immune crosstalk via SMAD7-HIF-1α-PKM2 cascade to attenuate septic liver injury
doi: 10.3389/fimmu.2025.1712741
Figure Lengend Snippet: HIF-1α and PKM2 are critical effectors of GDF15-driven mitochondrial protection and anti-inflammatory responses. (A) HIF-1α inhibition by BAY 87-2243 (5 μM, 24 h). β-actin: loading control.(Pharmacological HIF-1α blockade.) (B) PKM2 inhibition by Shikonin (2 μM, 24 h). β-actin: loading control.(PKM2 activity suppression.) (C) UQCRC1 recovery in LPS-injured macrophages treated with: GDF15 overexpression, HIF-1α inhibitor (BAY), or PKM2 inhibitor (Shikonin). β-actin: loading control.(Mitochondrial complex III rescue via HIF-1α/PKM2 inhibition mirrors GDF15 effects.) (D) Inflammatory (TNF-α, IL-6) and metabolic (lactate) markers in cell supernatant (n = 5). Study groups and individual replicates are identified in the figure key. ***p < 0.001.(HIF-1α/PKM2 targeting replicates GDF15-mediated anti-inflammatory and metabolic homeostasis.) (E) UQCRC1 expression under GDF15 loss-of-function: si-GDF15 alone vs. combined with BAY 87–2243 or Shikonin. β-actin: loading control. Study groups and individual replicates are identified in the figure key.(Mitochondrial rescue in GDF15-deficient macrophages requires HIF-1α/PKM2 inhibition.) (F) Supernatant cytokines and lactate in si-GDF15 macrophages with/without inhibitors (n = 5). ***p < 0.001. (Inflammation reversal in GDF15-knockdown macrophages depends on HIF-1α/PKM2 blockade.).
Article Snippet: Proteins (30 μg/lane) were separated on 10% SDS-PAGE gels, transferred to PVDF membranes (Millipore, IPVH00010), and probed with the following primary antibodies: rabbit anti-mouse UQCRC1 (Proteintech, Cat. No. 21705-1-AP, 1:1000), rabbit anti-mouse GDF15 (Proteintech, Cat. No. 27455-1-AP, 1:1000), rabbit anti-mouse HIF-1α (Proteintech, Cat. No. 20960-1-AP, 1:1000), rabbit anti-mouse SMAD7 (Proteintech, Cat. No. 725840-1-AP, 1:1000), mouse anti-mouse PKM2 (Proteintech, Cat. No. 60268-1-Ig, 1:1000), rabbit anti-mouse H3 (Proteintech, Cat. No. 17168-1-AP, 1:5000) and mouse anti-mouse β-actin (Proteintech, Cat. No. 66009-1-Ig, 1:5000).
Techniques: Inhibition, Control, Activity Assay, Over Expression, Expressing, Knockdown