Fig. 2

In vitro reduction in viral replication and proinflammatory cytokines through lipolysis inhibition. a, b Reduction in SARS-CoV-2 genome copy number and infectious progeny production by treatment of SARS-CoV-2-infected Vero E6 cells (MOI = 0.1 FFU) with atglistatin or CAY10499 at 20 µM. c, d Reduction in IAV genome copy number and infectious progeny production by treatment of IAV-infected A549 cells (MOI = 1 FFU) with 20 µM atglistatin or CAY10499 at 20 µM. e, f Inhibition of FFA and glycerol release from LDs by the treatment with 20 µM atglistatin or CAY10499 in SARS-CoV-2-infected Vero E6 cells at an MOI of 0.1 (e) or IAV-infected A549 cells at an MOI of 1 (f). g Retention of LDs (green) with corresponding inhibition of SARS-CoV-2 replication (red) by the treatment of virus-infected cells (MOI = 0.1 FFU) with 20 µM atglistatin or CAY10499. h Graphical representation of LC-MS data. Reduction in palmitic and oleic acids by treatment of IAV-infected A549 cells (MOI = 1 FFU) with 20 µM atglistatin or CAY10499 at 20 µM. i–l Increase in viral genome copy numbers and progeny numbers of IAV and SARS-CoV-2 through individual supplementation of exogenous palmitic, oleic, or linoleic acids in the above FFA-deprived condition. m Representative western blot. Reduction in IAV HA protein levels in knockdown conditions of ATGL and/or HSL in A549 cells infected with IAV PR8 strain (MOI = 1 FFU) or mock-infected controls. n (upper panels) Retention of LDs (green) with corresponding inhibition of IAV replication (red) by knockdown of ATGL and/or HSL in IAV-infected A549 cells (MOI = 1 FFU). Lower panels: reduction in pHSL (S563) level by knockdown of ATGL and/or HSL, resulting in the retention of LDs (green). o, p Reduction in IAV genome copy numbers and infectious progeny production in IAV-infected A549 cells (MOI = 1 FFU) by knockdown of ATGL and/or HSL. All data in the graphs are presented as arithmetic means ± SD from four independent experiments. *P < 0.05; **P < 0.01; ***P < 0.001, ****P < 0.0001, one-way analysis of variance with Tukey’s correction for multiple comparisons. Scale bars = 50 µm