Figure 1
Pioglitazone (PGZ) treatment alleviates sepsis-induced acute lung injury (ALI) in mice. A, Analysis of the 7-day survival rate in the sham group, PGZ group, ALI group, and ALI/PGZ group of mice. B, H&E staining was used to detect pathological changes in the lung tissues. Scale bar, 50 μm. Red arrows indicate interstitial thickening, pulmonary edema, and blood cell exudation, and black arrows indicate inflammatory cells infiltration. C, Wet/dry (W/D) weight ratio in lung tissues. A total of five mice were included in each experimental group. The data are reported as means±SD of five independent experiments. ANOVA was performed followed by Tukey's range test for post hoc comparisons between groups. ***P<0.001 ALI and ALI/PGZ groups vs sham group. ###P<0.001 ALI and ALI/PGZ groups vs PGZ group. ΔΔP<0.01 ALI/PGZ group vs ALI group.
Figure 2
Pioglitazone (PGZ) treatment upregulates peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) expression in the lung tissues. A and B, The expression levels of PGC-1α were detected by qRT-PCR (A) and western blot (B) in the lung tissues of the sham group, PGZ group, acute lung injury (ALI) group, and ALI/PGZ group of mice. A total of five mice were included in each experimental group. The data are reported as means±SD of five independent experiments. ANOVA was performed followed by Tukey's range test for post hoc comparisons between groups. *P<0.05, **P<0.01, ***P<0.001 PGZ, ALI, or ALI/PGZ groups vs sham group. ###P<0.001 ALI or ALI/PGZ groups vs PGZ group. ΔΔP<0.01 ALI/PGZ group vs ALI group.
Figure 3
Pioglitazone (PGZ) treatment reduces the inflammatory factors expression in the lung tissues of acute lung injury (ALI) mice. The levels of tumor necrosis factor (TNF)-α (A), interleukin (IL)-1β (B), IL-6 (C), and IL-10 (D) were detected by ELISA in in the lung tissues of the sham group, PGZ group, ALI group, and ALI/PGZ group of mice. A total of five mice were included in each experimental group. The data are reported as means±SD of five independent experiments. ANOVA was performed followed by Tukey's range test for post hoc comparisons between groups. *P<0.05 **P<0.01, ***P<0.001 ALI or ALI/PGZ groups vs sham group. ##P<0.01, ###P<0.001 ALI or ALI/PGZ groups vs PGZ group. ΔP<0.01, ΔΔP<0.01, ΔΔΔP<0.001 ALI/PGZ group vs ALI group.
Figure 4
Pioglitazone (PGZ) treatment upregulates peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) to prevent lipopolysaccharide (LPS)-stimulated macrophage M1 polarization. The expression levels of PGC-1α were detected by qRT-PCR (A) and western blot (B) in the blank, LPS, and PGZ groups of MH-S cells. C, The expression levels of iNOS, MHC-II, Arg1, and CD206 were detected by qRT-PCR in the blank, LPS, and PGZ groups of MH-S cells. *P<0.05, **P<0.01, ***P<0.001 LPS or PGZ groups vs blank group. ###P<0.001 PGZ group vs LPS group. The expression levels of PGC-1α were detected by qRT-PCR (D) and western blot (E) in the LPS, negative control (NC), and siPGC-1α groups of MH-S cells. F, The expression levels of iNOS, MHC-II, Arg1, and CD206 were detected by qRT-PCR in the LPS, NC, and siPGC-1α groups of MH-S cells. The data are reported as means±SD of three independent experiments. ANOVA was performed followed by Tukey's range test for post hoc comparisons between groups. *P<0.05, **P<0.01, ***P<0.001 NC or siPGC-1α groups vs LPS group. ##P<0.01, ###P<0.001 siPGC-1α group vs NC group.
Figure 5
Pioglitazone (PGZ) treatment upregulated peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) to modulate the expression of PPARγ and protect mitochondrial content and function. A, The quantitative analysis of mtDNA copy number were detected by qRT-PCR in the blank, lipopolysaccharide (LPS), PGZ, negative control (NC), and siPGC-1α groups of MH-S cells. B, The cellular reactive oxygen species (ROS) levels were detected by DHE staining in the blank, LPS, PGZ, NC, and siPGC-1α groups of MH-S cells. Scale bar, 50 μm. Right panel, the semi-quantification analysis of fluorescence intensity of DHE staining (three independent experiments). C, The expression levels of PPARγ and mitochondrial biogenesis-related proteins NRF1, NRF2, and mtTFA were detected by western blot in the blank, LPS, PGZ, NC, and siPGC-1α groups of MH-S cells. Right panel, graphs depict quantitative analysis of PPARγ, NRF1, NRF2, and mtTFA protein band densities (3 independent experiments). D, The relative mtDNA copy number was detected by qRT-PCR in the lung tissues of the sham group, PGZ group, acute lung injury (ALI) group, and ALI/PGZ group of mice. E, The cellular ROS levels were detected by DHE staining in the lung tissues of the sham group, PGZ group, ALI group, and ALI/PGZ group of mice. Scale bar, 50 μm. Right panel, the semi-quantification analysis of fluorescence intensity of DHE staining in the lung tissues. A total of five mice were included in each experimental group (five independent experiments). F, The expression levels of PPARγ and mitochondrial biogenesis-related proteins NRF1, NRF2, and mtTFA were detected by western blot in the lung tissues of the sham group, PGZ group, ALI group, and ALI/PGZ group of mice. Right panel, graphs depict quantitative analysis of protein band densities. A total of five mice were included in each experimental group (five independent experiments). ANOVA was performed followed by Tukey's range test for post hoc comparisons between groups. A-C, *P<0.05; **P<0.01; ***P<0.001 LPS, PGZ, NC, or siPGC-1α groups vs blank group. #P<0.05; ###P<0.001 PGZ, NC, or siPGC-1α groups vs LPS group. ΔΔΔP<0.01 PGZ or NC groups vs siPGC-1α group. D-F, *P<0.05; **P<0.01; ***P<0.001 ALI or ALI/PGZ groups vs sham group. #P<0.05; ##P<0.01; ###P<0.001 ALI or ALI/PGZ groups vs PGZ group. ΔΔΔP<0.01 ALI/PGZ group vs ALI group.