EZH2 upregulates the expression of MAPK1 to promote intervertebral disc degeneration via suppression of miR-129-5p

BACKGROUND

This study was designed to verify whether enhancer of zeste homolog 2 (EZH2) affects intervertebral disc degeneration (IVDD) development through regulation of microRNA (miR)-129-5p/MAPK1.

METHODS

Initially, we collected lumbar nucleus pulposus (NP) tissue samples from patients with juvenile idiopathic scoliosis (n = 14) and IVDD (n = 34). We measured the expression of related genes in clinical IVDD tissues and a lipopolysaccharide (LPS)-induced NP cell model. After loss- and gain- function assays, NP cell proliferation and senescence were examined. The targeting relationship between miR-129-5p and MAPK1 was explored by dual luciferase reporter gene and RIP assays. The enrichment of EZH2 and H3K27me3 in miR-129-5p promoter was verified by ChIP. Finally, an IVDD rat model was established to test the effects of transduction with lentiviral vector carrying miR-129-5p agomir and/or oe-EZH2 in vivo.

RESULTS

miR-129-5p was underexpressed, and EZH2 and MAPK1 levels are overexpressed in lumbar nucleus pulposus from human IVDD patients and in LPS-induced NP cells. miR-129-5p overexpression or silencing of MAPK1 promoted proliferation of NP cells, while inhibiting their senescence. EZH2 inhibited miR-129-5p through H3K27me3 modification in the miR-129-5p promoter. miR-129-5p could targeted the downregulation of MAPK1 expression. EZH2 overexpression increased the release of inflammatory factors and cell senescence factors, which was reversed by miR-129-5p agomir in vivo.

CONCLUSIONS

Taken together, EZH2 inhibits miR-129-5p through H3K27me3 modification, which upregulates MAPK1, thereby promoting the development of IVDD.

[Mechanism and material basis of Lianhua Qingwen capsule for improving clinical cure rate of COVID-19: a study based on network pharmacology and molecular docking technology]

OBJECTIVE

To explore the potential targets, signal pathways and biological functions that mediate the effect of Lianhua Qingwen capsule in improving clinical cure rate of COVID-19 in light of network pharmacology and molecular docking technology.

METHODS

TCMSP, Target, Prediction, CooLGeN, GeneCards, DAVID and other databases were searched for the active components and their target proteins from 13 herbs including Forsythia, Honeysuckle and roasted Ephedra used in Lianhua Qingwen capsule. The common target proteins, signal pathways and biological functions shared by these components and the clinical manifestations of COVID-19 (fever, cough, and fatigue) were identified to construct the network consisting of the component drugs in Lianhua Qingwen capsule, the active ingredients of, their targets of action, and the biological functions involved using Gephi software.

RESULTS

A total 160 active components including MOL000522, and MOL003283, MOL003365, MOL003006, MOL003014 in 13 component drugs in Lianhua Qingwen capsule produced therapeutic effects against COVID-19 through 57 target proteins including MAPK1, IL6, HSP90AA1, TNF, and CCL2, involving 35 signaling pathways including NOD-like receptor signaling pathway and Toll-like receptor signaling pathway. The results of molecular docking showed that 83 chemical components had total scores no less than 5.0 for docking with 12 target proteins (including MAPK1, IL6, and HSP90AA1) with high binding activities to form stable conformations. The binding of MOL000522, MOL004989, and MOL003330 with MAPK1; MOL001495 and MOL001494 with NLRP3; MOL004908, MOL004863 and MOL004806 with HSP90AA1; MOL001749 with TLR9; and MOL001495 with AKT1 all had total scores exceeding 9.0.

CONCLUSIONS

Lianhua Qingwen capsule contains multiple effective ingredients to improve clinical cure rate of COVID-19, and its therapeutic effect is mediated by multiple protein targets, signal pathways and biological functions.

Expression of Inflammatory and Cell Death Program Genes and Comet DNA Damage Assay Induced by Escherichia coli in Layer Hens

Modern methods of industrial poultry and egg production systems involve stressful practices that stimulate Escherichia coli (E. coli) activity causing endotoxic shock. This investigation was conducted to evaluate the expression of pro-inflammatory cytokines and cell death program genes and DNA damage induced by E. coli in the brain and liver tissues of laying hens. A total of two hundred and ten H&N brown layer hens with 20 week age, were used in this research. First, preliminary experiments were designed (60 hens in total) to establish the optimal exposure dose of E. coli and to determine the nearest time of notable response to be used in the remainder studies of this research. At 35-wk of age, 150 hens were randomly assigned into 2 groups with 3 replicates of 25 birds each; the first group was injected in the brachial wing vein with 10⁷E. coli colony/hen, while the second group was injected with saline and served as a control. The body temperature and plasma corticosterone concentration were measured 3 hr after injection. Specimens of liver and brain were obtained from each group and the gene expression of p38 mitogen-activated protein kinase, interlukin-1β (IL-1β), tumor necrosis factor alpha (TNF-α), Bax, and caspase-3 genes were measured by quantitative real-time PCR. DNA damage in the brain and liver tissues were also measured by comet assay. Hens treated with E. coli showed significant (P<0.05) increase of body temperature and plasma corticosterone (42.6°C and 14.5 ng/ml, respectively) compared to the control group (41.1°C and 5.5 ng/ml, respectively). Additional remarkable over-inflammation gene expression of p38, IL-1β and TNF-α.genes were also detected in the brain (2.2-fold, 2.0-fold and 3.3-fold, respectively) and the liver (2.1-fold, 1.9-fold and 3.0-fold, respectively) tissues of the infected chickens. It is also important to note that hens injected with E. coli showed an increase in DNA damage in the brain and liver cells (P<0.05). These results were synchronized with activating cell death program since our data showed significant high expression of Bax gene by 2.8- and 2.7-fold and caspase-3 gene by 2.5- and 2.7-fold in the brain and liver tissues of infected chickens, respectively (P<0.05). In conclusion, the current study indicates that E. coli injection induces inflammatory physiological response and triggers cell death program in the brain and liver. Our results provide more understanding to endotoxic shock by E. coli in chickens at cellular level. Further studies are required to confirm if such responses are destructive or protective to set the means through which a chicken mounts a successful defense against avian pathogenic E. coli.