Fig 2: Establishment of pulmonary arterial hypertension mouse model. (A) Schematic illustration of pulmonary arterial hypertension mouse model. (B–D) RVSP, RV/(LV + S), and RV/body weight at 3 weeks after chronic hypoxia exposure (n = 5 each). (E,F) Relative mRNA expression of PARM1 and CCDC80 normalized to a β-actin internal control (n = 5 each). Data are shown as mean ± SEM. * p < 0.05 vs. CON group (student’s t-test). CON, control mice without pulmonary arterial hypertension; HYPO, hypoxia; RVSP, right ventricle systolic pressure; RV, right ventricle; LV, left ventricle. S, septum.

Fig 3: PARM1 siRNA exhibited the anti-proliferation effects in PDGF/hypoxia-treated PASMCs. (A–G) Representative Western blots and quantification of PARM1, p-AKT(T308), p-AKT(S473), AKT, p-FOXO3A(S253), p-FOXO3A(S294), FOXO3A, and PCNA in cultured PASMCs under control or PDGF (30 ng/mL) conditions, plus treatment with si-RNA targeting PARM1 (si-PARM1) or negative control siRNA (si-NC). Equal protein loading was confirmed using an anti-β-actin antibody. (H–N) Representative Western blots and quantification of PARM1, p-AKT(T308), p-AKT(S473), AKT, p-FOXO3A(S253), p-FOXO3A(S294), FOXO3A, and PCNA in cultured PASMCs under control or hypoxia (1% O2) conditions, plus treatment with si-PARM1 or si-NC. Equal protein loading was confirmed using an anti-β-actin antibody. (O,Q) Representative EdU incorporation assay and quantification of the ratio of PASMCs incorporated with EdU under the control or PDGF (30 ng/mL) condition plus treatment with si-PARM1 or si-NC, in which nuclei stained with 1 X Hoechst 33342 (blue) and incorporated EdU merged with 1× Hoechst 33342 are shown in green (n = 3 random microscopic visions; Scale bar, 50 μm). (P,R) Representative EdU incorporation assay and quantification of the ratio of PASMCs incorporated with EdU under the control or hypoxia (1% O2) conditions, plus treatment with si-PARM1 or si-NC, in which nuclei stained with 1× Hoechst 33342 (blue) and incorporated EdU merged with 1× Hoechst 33342 are shown in green (n = 3 random microscopic visions; Scale bar, 50 μm). Data are shown as mean ± SEM; * p < 0.05 vs. CON group; # p < 0.05 vs. the CON + SiNC group; & p < 0.05 vs. the HYPO/PDGF + SiNC group; $ p < 0.05 vs. the HYPO/PDGF + SiNC group (student’s t-test). HYPO, hypoxia; PDGF, PDGF-BB.

Fig 4: Schematic illustration shows PARM1 promoting proliferation in the pulmonary arterial hypertension via the AKT/FOXO3A pathway in PASMC. P signifies phosphorylation.

Fig 5: Validation of the screened hub gene in hypoxia-induced PAH mouse model. (A,H,I) Representative Western blots and analysis of PARM1 and PCNA expression in mouse lung. Equal protein loading was confirmed using an anti-β-actin antibody (n = 5 each). (B) Linear regression analysis of the association between PARM1 and PCNA expression in mouse lung. (C–G) Representative Western blots and analysis of p-AKT(T308)/AKT ratio; p-AKT(S473)/AKT ratio; p-FOXO3A(S253)/FOXO3A ratio; p-FOXO3A(S294)/FOXO3A ratio in mouse lung. Data are shown as mean ± SEM (n = 5 each); * p < 0.05 vs. CON group; ns represents “not significant” (student’s t-test).