RESUMO
Using the concepts and methods of epigenetics and metabolomics, to investigate the overall action molecular mechanism of Chrysanthemi indici C (CIC), the anti-hepatitis B virus (HBV) active extracts from Flos chrysanthemi indici. The inhibitory effects of CIC on proliferation and hepatitis B surface antigen (HBsAg), hepatitis B envelope antigen (HBeAg) and HBV-DNA of HepG2.2.15 cells were detected by CCK-8 and antigen kit. The DNA methyltransferases (DNMTs)/ten-eleven-translocation-2 (TET2) equilibrium was detected by ELISA. Illumina 850K methylation chip, pyrosequencing and qPCR were used to determine the action pathway and target of CIC by GO and KEGG analysis. Cell metabolites were extracted with 80% methanol, and the changes of differential metabolites, differential metabolic pathways and cell microenvironment were detected by LC-MS and other metabolomics methods. The results showed that CIC could inhibit the proliferation, HBsAg, HBeAg and HBV-DNA of HepG2.2.15 cells obviously, down-regulate DNA methyltransferase 1 (DNMT1), DNA methyltransferase 3a (DNMT3a) and DNA methyltransferase 3b (DNMT3b), up-regulate TET2, and restore the balance of DNMTs/TET2. The action targets of CIC were phospholipase C gamma 2 (PLCG2), phosphoinositide-3-kinase regulatory subunit 3 (PIK3R3), 1-acylglycerol-3-phosphate O-acyltransferase 2 (AGPAT2), 5-hydroxytryptamine receptor 2B (HTR2B), nerve growth factor (NGF), mainly involved in lipid metabolism, inflammation mediated regulation of transient receptor potential (TRP), phospholipase D signaling and advanced glycation end product-receptor for AGE (AGE-RAGE) signaling in diabetic complications pathways. CIC could significantly affect fatty acid metabolism and had great influence on phenolic acid, alkaloid and lipid metabolites in cell microenvironment. These results suggest that the action mechanism of CIC may be the synergistic action of multiple pathways and multiple targets, including related inflammatory pathways, immune pathways and lipid metabolism, through regulating epigenetic expression balance and restoring the balance of cell microenvironment.
RESUMO
Increasing evidence suggests that cytokines and chemokines play crucial roles in chronic itch. In the present study, we evaluated the roles of tumor necrosis factor-alpha (TNF-α) and its receptors TNF receptor subtype-1 (TNFR1) and TNFR2 in acute and chronic itch in mice. Compared to wild-type (WT) mice, TNFR1-knockout (TNFR1-KO) and TNFR1/R2 double-KO (DKO), but not TNFR2-KO mice, exhibited reduced acute itch induced by compound 48/80 and chloroquine (CQ). Application of the TNF-synthesis inhibitor thalidomide and the TNF-α antagonist etanercept dose-dependently suppressed acute itch. Intradermal injection of TNF-α was not sufficient to evoke scratching, but potentiated itch induced by compound 48/80, but not CQ. In addition, compound 48/80 induced TNF-α mRNA expression in the skin, while CQ induced its expression in the dorsal root ganglia (DRG) and spinal cord. Furthermore, chronic itch induced by dry skin was reduced by administration of thalidomide and etanercept and in TNFR1/R2 DKO mice. Dry skin induced TNF-α expression in the skin, DRG, and spinal cord and TNFR1 expression only in the spinal cord. Thus, our findings suggest that TNF-α/TNFR1 signaling is required for the full expression of acute and chronic itch via peripheral and central mechanisms, and targeting TNFR1 may be beneficial for chronic itch treatment.