ABSTRACT
BACKGROUND: Echinococcus multilocularis is the causative agent of human hepatic alveolar echinococcosis (AE). AE can cause damage to several organs, primarily the liver, and have severe outcomes, such as hepatic failure and encephalopathy. The main purpose of this study was to explore the interactions between hepatic stellate cells (HSCs) and E. multilocularis protoscoleces (PSCs). The results of this study provide an experimental basis for further examination of the pathogenesis of hepatic fibrosis due to AE infection. METHODS: We investigated the role of Echinococcus multilocularis (Echinococcus genus) PSCs in hepatic fibrosis by examining structural changes and measuring hepatic fibrosis-related protein levels in cocultures of PSCs and human HSCs. Structural changes were detected by transmission electron microscopy (TEM), and levels of the hepatic fibrosis-related proteins collagen I (Col-I), alpha-smooth muscle actin (α-SMA) and osteopontin (OPN) were measured by western blotting and enzyme-linked immunosorbent assay (ELISA). RESULTS: Under coculture (1) both PSCs and HSCs exhibited morphological changes, as observed by TEM; (2) Col-I, α-SMA, and OPN expression levels, which were determined by western blotting and ELISA, significantly increased after 3 days of incubation. CONCLUSIONS: The results of this study provide insights into the molecular mechanisms of AE-induced hepatic fibrosis.
Subject(s)
Actins/analysis , Collagen/analysis , Echinococcosis, Hepatic/parasitology , Echinococcus multilocularis/ultrastructure , Liver Cirrhosis/parasitology , Osteopontin/analysis , Animals , Coculture Techniques , Echinococcosis, Hepatic/complications , Echinococcus multilocularis/metabolism , Gerbillinae , Hepatic Stellate Cells/parasitology , Hepatic Stellate Cells/ultrastructure , Humans , Liver/parasitology , Liver/pathology , Liver Cirrhosis/etiology , Liver Cirrhosis/pathology , Male , Microscopy, Electron, TransmissionABSTRACT
Glycogen synthase kinase-3 (GSK3), a cytoplasmic serine/threonine-protein kinase involved in a large number of key cellular processes, is a little-known signaling molecule in virus study. In this study, a GSK3 protein which was highly similar to GSK3ß homologs from other species in Litopenaeus vannamei (designated as LvGSK3ß) was obtained. LvGSK3ß was expressed constitutively in the healthy L. vannamei, at the highest level in the intestine and the lowest level in the eyestalk. White spot syndrome virus (WSSV) reduced LvGSK3ß expression was in immune tissues including the hemocyte, intestine, gill and hepatopancreas. The inhibition of LvGSK3ß resulted in significantly higher survival rates of L. vannamei during WSSV infection than the control group, and significantly lower WSSV viral loads in LvGSK3ß-inhibited L. vannamei were observed. Knockdown of LvGSK3ß by RNAi resulted in increases in the expression of LvDorsal and several NF-κB driven antimicrobial peptide (AMP) genes (including ALF, PEN and crustin), but a decrease in LvCactus expression. Accordingly, overexpression of LvGSK3ß could reduce the promoter activity of LvDorsal and several AMPs, while the promoter activity of LvCactus was increased. Electrophoretic mobility shift assays (EMSA) showed that LvDorsal could bind to the promoter of LvGSK3ß. The interaction between LvGSK3ß and LvDorsal or LvCactus was confirmed using co-immunoprecipitation (Co-IP) assays. In addition, the expression of LvGSK3ß was dramatically reduced by knockdown of LvDorsal. In summary, the results presented in this study indicated that LvGSK3ß had a negative effect on L. vannamei by mediating a feedback regulation of the NF-κB pathway when it is infected by WSSV.
Subject(s)
Arthropod Proteins/metabolism , Glycogen Synthase Kinase 3 beta/metabolism , NF-kappa B/metabolism , Penaeidae/virology , White spot syndrome virus 1/pathogenicity , Animals , Binding Sites , DNA-Binding Proteins/metabolism , Gene Expression Regulation , Glycogen Synthase Kinase 3 beta/genetics , Host-Pathogen Interactions , Penaeidae/enzymology , Penaeidae/genetics , Promoter Regions, Genetic , Signal TransductionABSTRACT
MicroRNAs belong to a newly identified class of small non-coding RNAs that have been widely implicated in the fine-tuning of many physiological processes such as the pathogenesis of type 2 diabetes (T2D) and obesity. Microarray studies have highlighted an altered profile of miRNA expression in insulin target tissues in diabetic and obese models. Emerging evidences suggest that miRNAs play significant roles in insulin production, secretion and actions, as well as in diverse aspects of glucose homeostasis and adipocyte differentiation. The identification of tissue-specific miRNAs implicated in T2D and obesity might be useful for the future development of effective strategies for early diagnosis and therapeutic intervention of obesity-related medical complications.