SP1 and UTE1 Decoy ODNs inhibit activation and proliferation of hepatic stellate cells by targeting tissue inhibitors of metalloproteinase 1

Analysis of key genes and related transcription factors in liver fibrosis based on bioinformatic technology

OBJECTIVE

To analyze differentially expressed genes (DEGs) related to liver fibrosis, and clarify the key genes and the possible targets in the progression of liver fibrosis.

METHODS

Using microarray datasets, GSE38199 was extracted from Gene Expression Omnibus (GEO), and a bioinformatics method was performed to find DEGs and transcription factors related to liver fibrosis.

RESULTS

A total of 58 DEGs were screened out according to GEO2R online analysis tool, which included 49 up-regulated and 9 down-regulated genes. These DEGs were mainly involved in formation with the extracellular region and extracellular exosome through gene ontology (GO) enrichment analysis. Kyoto Encyclopedia of Gene and Genome (KEGG) pathway enrichment analysis showed that DEGs mainly participated in the PI3K-Akt signaling pathway, focal adhesion, ECM-receptor interaction, and metabolic pathways. Based on the results of the Protein-Protein Interaction (PPI) network and Molecular Complex Detection (MCODE) analysis, 9 key genes (COL1A1, FBN1, BGN, COL6A3, MMP2, FBLN5, LUM, PDGFRB, LOXL1) were screened out. A total of 30 transcription factors were found according to these 9 key genes, of which 4 transcription factors (Stat3, Trp53, NF-κB1, Sp1) were enriched.

CONCLUSION

Stat3, Trp53, NF-κB1, and Sp1 were all related to the development of liver fibrosis, and FBLN5 might be a target for liver fibrosis.

Class C1 decoy oligodeoxynucleotide inhibits profibrotic genes expression in rat hepatic stellate cells

The aim of the present study was to investigate whether class C1 decoy oligodeoxynucleotides (ODNs) can inhibit the expression of pro‑fibrotic genes associated with rat hepatic stellate cell (HSC) activation and hepatic fibrosis. Luciferase reporter assays were performed to test the promoter activities of transforming growth factor (TGF)‑β and its downstream target genes following transfection of decoy ODNs and plasmids into HSC‑T6 cells, and western blot assays were performed to measure the protein expression of those genes following decoy ODN transfection. Class C1 decoy ODNs were confirmed to inhibit the promoter activity of TGF‑β and its downstream target genes, such as type 1 collagen (COLI)α1, tissue inhibitor of metalloproteinases (TIMP)1 and α‑smooth muscle actin by Gaussia luciferase reporter assay, and to further downregulate the expression of TGF‑β, SMAD3, COLIα1 and TIMP1 by western blotting in activated HSC‑T6 cells. In conclusion, class C1 decoy ODNs inhibited pro‑fibrotic gene expression in rat HSCS by downregulating TGF‑β signaling.

Transcription Factor Sp1 Regulates the Expression of Calcium Channel α2δ-1 Subunit in Neuropathic Pain

High voltage-activated (HVA) Ca²⁺ (Ca_V) channels are oligomeric complexes formed by an ion-conducting main subunit (Cavα₁) and at least two auxiliary subunits (Cavβ and Ca_Vα₂δ). It has been reported that the expression of Ca_Vα₂δ1 increases in the dorsal root ganglia (DRGs) of animals with mechanical allodynia, and that the transcription factor Sp1 regulates the expression of the auxiliary subunit. Hence, the main aim of this work was to investigate the role of Sp1 as a molecular determinant of the exacerbated expression of Ca_Vα₂δ-1 in the nerve ligation-induced model of mechanical allodynia. Our results show that ligation of L5/L6 spinal nerves (SNL) produced allodynia and increased the expression of Sp1 and Ca_Vα₂δ-1 in the DRGs. Interestingly, intrathecal administration of the Sp1 inhibitor mithramycin A (Mth) prevented allodynia and decreased the expression of Sp1 and Ca_Vα₂δ-1. Likewise, electrophysiological recordings showed that incubation with Mth decreased Ca²⁺ current density in the DRG neurons, acting mostly on HVA channels. These results suggest that L5/L6 SNL produces mechanical allodynia and increases the expression of the transcription factor Sp1 and the subunit Ca_Vα₂δ-1 in the DRGs, while Mth decreases mechanical allodynia and Ca²⁺ currents through HVA channels in sensory neurons by reducing the functional expression of the Ca_Vα₂δ-1 subunit.