Fig. 1

Baicalein interferes mitochondrial OXPHOS in a mPTP dependent manner and inhibits replication of SARS-CoV-2/VSV. a Baicalein structure. b RT-qPCR assays for SARS-CoV-2 RNA amplification in medium of Vero E6 cells show Baicalein inhibits SARS-CoV-2 replication. Mean ± sd; n = 3. c quantification of images (as of Fig. S1d) for VSV-GFP replication at different M.O.I. in the presence of increasing dose of Baicalein. d RT-qPCR assays show Baicalein dose dependently inhibits VSV RNA amplification in Vero E6 cells. Mean ± sd; n = 3. e Western blot shows Baicalein dose dependently blocks VSV-G protein expression in VSV-GFP infected Vero E6 cells. f Graph shows OCR measured by seahorse analyzer. OCR inhibition of Vero E6 cells by different dose of Baicalein (18 min), Oligomycin A (Oligo, 36 min) Fccp (54 min) and Rotenone/Antimycin A (Rot/AA, 72 min). n = 3; mean ± s.e.m. g Quantification of relative proton leakage from seahorse analyzer data as in f. h Western blot shows enhanced induction of ATF4 by Baicalein in the presence of mPTP inhibitor, CsA. i Quantification of flow cytometry data for TMRE signal (as in Supplementary Fig. S4a) indicates increased TMRE signal by VSV-GFP infection in Vero E6 cells. No significant difference of TMRE signal between VSV-GFP infected or none infected cells in the presence of mPTP inhibitor, CsA. j Representative image for VSV–GFP replication at different M.O.I. in the presence of CsA or not. k Quantification of j. l RT-qPCR assays for SARS-CoV-2 RNA amplification in medium of Vero E6 cells treated as indicated. Mean ± SD; n = 3. m Quantification of images (as in Fig. S4f) for VSV-GFP replication in Vero E6 cells treated as indicated. MOI multiplicity of infection; *p < 0.05; **p < 0.01