Journal: Redox Biology
Article Title: Prophylactic C-terminal occludin–derived peptide attenuates LPS-induced airway inflammation via barrier preservation and mitochondrial ROS regulation
doi: 10.1016/j.redox.2026.104119
Figure Lengend Snippet: The peptide regulates mitochondrial dysfunction and ROS production by inhibiting LPS-induced p38 activation. (A) The BEAS-2b cells were treated with wild-type occludin peptide (pepWT OCLN) or mutant occludin peptide (pepMut OCLN) and incubated with LPS for 15, 30 min. The phospho-specific and total antibodies were assessed by Western blot analysis. β-actin was used as a loading control. (B) The BEAS-2b cells were transfected with p38 overexpression construct (WT p38) or siRNA-p38 for 24 h and incubated with LPS for 4 h siRNA-scramble was used as a negative control. The proinflammatory cytokine transcripts were assessed by qRT-PCR. ∗ p < 0.05 compared with control; ∗∗ p < 0.05 compared with LPS treatment; ∗∗∗ p < 0.05 compared with WT p38-transfected cells. (C) The mitochondrial membrane potential of LPS-induced BEAS-2b cells treated with either WT OCLN peptide or mut peptide was stained with JC-1 dye. Images are representative results of 3 independent experiments. (D) The mitochondria fission was stained using phospho-Drp1 antibody and visualized. The fluorescence intensity was analyzed and statistically evaluated (right panel). ∗ p < 0.05 compared with control; ∗∗ p < 0.05 compared with LPS treatment; ∗∗∗ p < 0.05 compared with WT OCLN peptide-treated transfectants. (E) After the BEAS-2b cells were harvested, cell lysates were used for MTT assay. (F) After mitochondria from the cells was isolated, the mitochondria lysates were used for mtROS measurement. ∗ p < 0.05 compared with control; ∗∗ p < 0.05 compared with LPS only; ∗∗∗ p < 0.05 compared with LPS- and WT occludin peptide-treated cells. All data shown are representative of three independent experiments.
Article Snippet: Proteome Profiler Human Cytokine Array kit was purchased from R&D Systems (cat no. ARY005B, USA).
Techniques: Activation Assay, Mutagenesis, Incubation, Western Blot, Control, Transfection, Over Expression, Construct, Negative Control, Quantitative RT-PCR, Membrane, Staining, Fluorescence, MTT Assay, Isolation