Journal: Circulation research
Article Title: Altered Smooth Muscle Cell Histone Acetylome by the SPHK2/S1P Axis Promotes Pulmonary Hypertension
doi: 10.1161/CIRCRESAHA.123.322740
Figure Lengend Snippet: (A) RNA-seq data of SPHK2, KLF4 and AIMP1 in iPAH: PASMCs and non-iPAH:PASMCs in log2-fold of count per million (cpm). Following two-way ANOVA, Sidak’s multiple comparisons test for logarithmic values, n=4. (B) Representative immunoblot probed for KLF4, SPHK2, tubulin, Ac-H3K9 and total histone H3 in whole cell lysates of non: iPAH or iPAH PASMCs with scramble or SPHK2 siRNA transfection and, quantification of (C) Ac-H3K9/total histone H3 and, (D) KLF4/Tubulin, n=3 (E) KLF4 expression levels normalized against 18S rRNA in non: iPAH or iPAH PASMCs with scramble or SPHK2 siRNA transfection, n=4. (F) Cell proliferation rate of non: iPAH or iPAH PASMC with or without iSPHK2 pretreatment for 24 hours, n=4. (G) The proposed model: Endothelial monocyte activating polypeptide II (EMAP II) plays a key role in reawakening pluripotency factor, KLF4 in human pulmonary artery smooth muscle cells (PASMCs) through stimulation of the nuclear SPHK2/S1P epigenetic modulating axis, suggesting that cooperation between SPHK2 and EMAP II could be a major driving force for epigenetic-mediated vascular PASMCs reprogramming and remodeling in PH. Ablation of SPHK2 expression confers protection against PH by rescuing the global and local transcription machinery from histone acetylation and activation of the pluripotency factor, KLF4. P values are calculated using Kruskal-Wallis against iPAH or Kolmogorov-Smirnov non-parametric test if not mentioned otherwise, and results are shown as median and inter-quartile range.
Article Snippet: Primary human PASMCs (hPASMCs), pulmonary microvascular endothelial cells (hPMVECs) purchased from Lonza (Walkersville, MD) and iPAH: PASMCs were cultured in complete growth medium or conditioned media in a humidified atmosphere or 1% O 2 with 5% CO 2 at 37° C. For all studies, passages 5–10 were used for hPASMCs and hPMVECs.
Techniques: RNA Sequencing, Western Blot, Transfection, Expressing, Activation Assay