Cytoskeletal proteins: shaping progression of hepatitis C virus-induced liver disease

Overview of the compromised mucosal integrity in celiac disease

Intestinal epithelium is a dynamic cellular layer that lines the small-bowel and makes a relatively impenetrable barrier to macromolecules. Intestinal epithelial cell polarity is crucial in coordinating signalling pathways within cells and mainly regulated by three conserved polarity protein complexes, the Crumbs (Crb) complex, partitioning defective (PAR) complex, and Scribble (Scrib) complex. Polarity proteins regulate the proper establishment of the intercellular junctional complexes including tight junctions (TJs), adherence junctions (AJs), and desmosomes which hold epithelial cells together and play a major role in maintaining intestinal barrier integrity. Impaired intestinal epithelial cell polarity and barrier integrity result in irreversible immune responses, the host- microbial imbalance and intestinal inflammatory disorders. Disassembling the epithelial tight junction and augmented paracellular permeability is a conspicuous hallmark of celiac disease (CD) pathogenesis. There are several dietary components that can improve intestinal integrity and function. The aim of this review article is to summarize current information about the association of polarity proteins and AJC damages with pathogenesis of CD.

Potential roles of core and core+1 proteins during the chronic phase of hepatitis C virus infection

The HCV Core protein is a multifunctional protein that interacts with many viral and cellular proteins. In addition to the encapsidation of the viral genome, it can disturb various cellular pathways and impede antiviral cellular responses such as interferon (IFN) production. The Core protein can also disrupt the functions of immune cells against HCV. The Core protein helps viral infection persistency by interfering with apoptosis. The Core+1 protein plays a significant role in inducing chronic HCV infection through diverse mechanisms. We review some of the mechanisms by which Core and Core+1 proteins facilitate HCV infection to chronic infection. These proteins could be considered for designing more sufficient treatments and effective vaccines against HCV.

Effects and mechanism of siomycin A on the growth and apoptosis of MiaPaCa-2 cancer cells

Siomycin A is a type of thiopeptide antibiotic that is isolated from the fermentation products of an endophytic actinomycin, which is derived from the medicinal plant Acanthopanax senticosus. The present study investigated whether siomycin A has antitumor effects in vitro on a variety of cell lines. A Cell Counting Kit-8 assay was performed to detect the effects of siomycin A on cell viability; morphological changes in the MiaPaCa-2 cell line were analyzed using an inverted phase contrast microscope. A Transwell migration assay was applied to detect cell migration ability. The cytoskeleton was observed by laser confocal microscopy, and apoptosis was detected using flow cytometry. A western blot assay was used to detect the expression of matrix metalloproteinase (MMP)-2, MMP-9 and α-tubulin. The results revealed that siomycin A inhibited the proliferation of human tumor cell lines of different origins. As the concentration of siomycin A increased, the cell density decreased gradually and cells exhibited a morphological change from spindle to spherical shape. Furthermore, 24 h after administration, the cell migration ability was inhibited. The cytoskeleton complexity and morphological changes were increased after administration of siomycin A. The percentage of apoptotic cells was significantly increased and the expression levels of MMP-2, MMP-9 and α-tubulin were downregulated by siomycin A. Therefore, siomycin A was determined to effectively inhibit the proliferative ability of a variety of human tumor cell lines. Siomycin A was also determined to affect the cytoskeleton of tumor cells by downregulating the expression of α-tubulin protein.