Pleurotus nebrodensis polysaccharide (PN-S) enhances the immunity of immunosuppressed mice / 中国天然药物

In the present study, the effects of Pleurotus nebrodensis polysaccharide (PN-S) on the immune functions of immunosuppressed mice were determined. The immunosuppressed mouse model was established by treating the mice with cyclophosphamide (40 mg/kg/2d, CY) through intraperitoneal injection. The results showed that PN-S administration significantly reversed the CY-induced weight loss, increased the thymic and splenic indices, and promoted proliferation of T lymphocyte, B lymphocyte, and macrophages. PN-S also enhanced the activity of natural killer cells and increased the immunoglobulin M (IgM) and immunoglobulin G (IgG) levels in the serum. In addition, PN-S treatment significantly increased the phagocytic activity of mouse peritoneal macrophages. PN-S also increased the levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interferon-γ (INF-γ), and nitric oxide (NOS) in splenocytes. qRT-PCR results also indicated that PN-S increased the mRNA expression of IL-6, TNF-α, INF-γ, and nitric oxide synthase (iNOS) in the splenocytes. These results suggest that PN-S treatment enhances the immune function of immunosuppressed mice. This study may provide a basis for the application of this fungus in adjacent immunopotentiating therapy against cancer and in the treatment of chemotherapy-induced immunosuppression.

Study Progress of Cu,Zn Superoxide Dismutas——From Gene to Function / 现代生物医学进展

Superoxide Dismutase (SOD)(EC 1.15.1.1)is a metalloenzyme that is found in almost all organisms and catalyzes the dismutation of superoxide anion radical to hydrogen peroxide and molecular oxygen. Three unique and highly compartmentalized mammalian SOD have been biochemically and molecularly characterized to date: Cu, Zn superoxide dismutase (CuZnSOD, SOD1), MnSOD (Manganese Superoxide Dismutase, SOD2)and EC-SOD (Extracellular Superoxide Dismutase, SOD3). Cu, Zn superoxide dismutase (CuZnSOD, SOD1)is a copper and zinc-containing homodimer that is found almost exclusively in intracellular cytoplasmic spaces. CuZnSOD is widely distributed and comprises about 90% of the total SOD. Cytoplasmic and periplasmic SOD exists as dimers,whereas chloroplastic and extracellular enzymes exist as tetramers. Structure supports independent functional evolution in prokaryotes and eukaryotes. CuZnSOD are thought to protect the brain, lungs, and other tissues from oxidative stress. This paper reviewed the gene, molecular and chemical structure and biological function of CuZnSOD.

Study Progress of Cu,Zn Superoxide Dismutas——From Gene to Function / 现代生物医学进展

Superoxide Dismutase (SOD)(EC 1.15.1.1)is a metalloenzyme that is found in almost all organisms and catalyzes the dismutation of superoxide anion radical to hydrogen peroxide and molecular oxygen. Three unique and highly compartmentalized mammalian SOD have been biochemically and molecularly characterized to date: Cu, Zn superoxide dismutase (CuZnSOD, SOD1), MnSOD (Manganese Superoxide Dismutase, SOD2)and EC-SOD (Extracellular Superoxide Dismutase, SOD3). Cu, Zn superoxide dismutase (CuZnSOD, SOD1)is a copper and zinc-containing homodimer that is found almost exclusively in intracellular cytoplasmic spaces. CuZnSOD is widely distributed and comprises about 90% of the total SOD. Cytoplasmic and periplasmic SOD exists as dimers,whereas chloroplastic and extracellular enzymes exist as tetramers. Structure supports independent functional evolution in prokaryotes and eukaryotes. CuZnSOD are thought to protect the brain, lungs, and other tissues from oxidative stress. This paper reviewed the gene, molecular and chemical structure and biological function of CuZnSOD.