Project description:Fomitiporia species have aroused the interest of numerous investigations that reveal their biological activity and medicinal potential. The present investigation shows the antioxi-dant, anticancer, and immunomodulatory activity of acidic polysaccharides obtained from the fungus Fomitiporia chilensis. The acidic polysaccharides were obtained for acidic precipitation with 2% O-N-cetyl pyridinium bromide. Chemical analysis was performed by FT-IR and GC-MS methods. The antioxidant capacity of acidic polysaccharides from F. chilensis was evaluated by the scavenging of free radicals with the ABTS and DPPH as-says. Macrophages proliferation and cytokine production assays were used to determine the immunomodulatory capacity of the polysaccharides. Anti-tumor and cytotoxicity ac-tivity was evaluated with MTT assay in the U-937, HTC-116, and HGF-1 cell lines. The ef-fect of polysaccharides on the cell cycle of the HCT-116 cell line was determined for flow cytometry. Fourier Transform-infrared characterization revealed characteristic absorption peaks for polysaccharides, whereas the GC-MS analysis detected three peak correspond-ing to D-galactose, galacturonic acid and D-glucose. The TNF-α proliferation was in-creased when the cell was treated with 2 mg/mL polysaccharides, whereas the IL-6 con-centration was increased with all polysaccharide concentrations evaluated. The cell cycle analysis of HTC-116 treated with polysaccharides evidenced that the acidic polysaccha-rides from F. chilensis induce an increase in the G0/G1 cell cycle phase, incrementing the apoptotic cell percentage. A proteomic analysis suggested some of the molecular mecha-nisms involved in their antioxidant and cellular detoxifying effects and justified their tra-ditional use in heart diseases.
Project description:Nested parasitic chains are common schemes in nature, not limited to cellular organisms. Some giant viruses infecting protists are hyperparasitized by smaller viruses named virophages. Both can carry episomal plasmid-like DNA molecules known as transpovirons in their particles. They all share common transcriptional regulatory elements dictating the expression of their genes, which are transcribed within viral factories built by giant viruses in the host cytoplasm. This suggests close but as yet undetermined interactions between their respective transcriptional networks. Here, we studied the protein content of Megavirus chilensis virions produced in Acanthamoeba castellanii cells co-infected or not with the virophage Zamilon vitis.
