Connective Tissue Growth Factor Neutralization Aggravates the Psoriasis Skin Lesion: The Analysis of Psoriasis Model Mice and Patients

Construction of a three commitment points for S phase entry cell cycle model and immune-related ceRNA network to explore novel therapeutic options for psoriasis

While competing endogenous RNAs (ceRNAs) play pivotal roles in various diseases, the proliferation and differentiation of keratinocytes are becoming a research focus in psoriasis. Therefore, the three commitment points for S phase entry (CP1-3) cell cycle model has pointed to a new research direction in these areas. However, it is unclear what role ceRNA regulatory mechanisms play in the interaction between keratinocytes and the immune system in psoriasis. In addition, the ceRNA network-based screening of potential therapeutic agents for psoriasis has not been explored. Therefore, we used multiple bioinformatics approaches to construct a ceRNA network for psoriasis, identified CTGF as the hub gene, and constructed a ceRNA subnetwork, after which validation datasets authenticated the results' accuracy. Subsequently, we used multiple online databases and the single-sample gene-set enrichment analysis algorithm, including the CP1-3 cell cycle model, to explore the mechanisms accounting for the increased proliferation and differentiation of keratinocytes and the possible roles of the ceRNA subnetwork in psoriasis. Next, we performed cell cycle and cell trajectory analyses based on a single-cell RNA-seq dataset of psoriatic skin biopsies. We also used weighted gene co-expression network analysis and single-gene batch correlation analysis-based gene set enrichment analysis to explore the functions of CTGF. Finally, we used the Connectivity Map to identify MS-275 (entinostat) as a novel treatment for psoriasis, SwissTargetPrediction to predict drug targets, and molecular docking to investigate the minimum binding energy and binding sites of the drug to target proteins.

M2-polarized macrophages mediate wound healing by regulating connective tissue growth factor via AKT, ERK1/2, and STAT3 signaling pathways

BACKGROUND

Timely and sufficient M1 recruitment and M2 polarization are necessary for fibrosis during wound healing. The mechanism of how M2 mediates wound healing is worth exploring. Abnormally up-regulated connective tissue growth factor (CTGF) influences multiple organ fibrosis, including cardiac, pulmonary, hepatic, renal, and cutaneous fibrosis. Previous studies reported that M2 contributed to hepatic and renal fibrosis by secreting CTGF. It is worth discussing if M2 regulates fibrosis through secreting CTGF in wound healing.

METHODS AND RESULTS

We established the murine wound model and inhibited macrophages during proliferation phase with clodronate liposomes in vivo. Macrophages depletion led to down-regulation of wound healing rates, collagen deposition, as well as expression of collagen 1/3 and Ki67. M2 was induced by interleukin-4 (IL-4) and measured by flow cytometry in vitro. Secreted pro-fibrotic and anti-fibrotic factors were tested by enzyme-linked immunosorbent assay (ELISA). M2 was polarized, which producing more CTGF, transforming growth factor-beta1 (TGF-β1), and IL-6, as well as less tumor necrosis factor-α (TNF-α) and IL-10. M2 CTGF gene was blocked using siCTGF. Effects of M2 on fibroblasts activities were detected by cell counting kit 8 (CCK8) and cellular wound healing assay. Expressions of related signaling pathway were assessed by western blotting. Blockade of CTGF in M2 deactivated fibroblasts proliferation and migration by regulating AKT, ERK1/2, and STAT3 pathway. Recombinant CTGF restored these effects.

CONCLUSIONS

Our research, for the first time, indicated that M2 promoted wound healing by secreting CTGF, which further mediating proliferation and migration of fibroblasts via AKT, ERK1/2, and STAT3 pathway.

Transcriptomic profiles of human HaCaT cells in response to angelica polysaccharide

The aim of this study was to explore the anti-psoriatic effect and potential mechanism of Angelica polysaccharide (APS) on an in vitro HaCaT cell model. MTS assay was performed to determine whether APS has the ability to inhibit the proliferation of HaCaT cells. RNA-sequencing (RNA-seq) was performed to investigate the underlying mechanism of APS. Quantitative real-time PCR (qRT-PCR) was used to verify the accuracy of RNA-seq data. Our MTS assay results demonstrated that APS time- and concentration-dependently inhibits the proliferation of HaCaT cells. The anti-proliferation property of APS suggests that APS may have anti-psoriatic effect. In the RNA-seq part, comparison between the CK group (i.e., Control group) and ASP groups revealed dramatic differences [468 differentially expressed genes (DEGs) for CK group vs. ASP50 group; 563 DEGs for CK group vs. ASP100 group; 532 DEGs for CK group vs. ASP200 group]. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrich analysis performed on all DEGs failed to find any significant enriched GO terms or KEGG pathways to explain the anti-proliferative effect of APS. All DEGs were then classified into 20 expression profiles by trend analysis. Interestingly, cell proliferation-related GO terms were mostly dispersed in the profile 2 and 17. DEGs enriched in these terms were then analyzed. After literature retrieval, DEGs such as SERPINE1, SMAD6, CTGF, and TGF-β were suspected to closely relevant to the anti-proliferation effect of APS. qRT-PCR results showed similar expression trend with RNA-seq data for 8 out of 10 genes, indicating our sequence data are reliable.