title: Saussurea tridactyla Sch. Bip.-derived polysaccharides and flavones reduce oxidative damage in ultraviolet B-irradiated HaCaT cells via a p38MAPK-independent mechanism.
abstract: OBJECTIVE
  To investigate whether Saussurea tridactyla Sch. Bip.-derived polysaccharides and flavones exert apoptosis-inhibiting effects in ultraviolet B (UVB)-irradiated HaCaT cells.
  
  
  METHODS
  We divided HaCaT cells into low radiation UVB and high radiation UVB groups. Low radiation UVB and high radiation UVB groups were further divided into a control group, UVB radiation group (UVB group), S. tridactyla Sch. Bip.-derived polysaccharides and flavones low-dose group, and S. tridactyla Sch. Bip.-derived polysaccharides and flavones high-dose group. Cell viability and morphology were assayed by MTT and trypan blue staining. Superoxide dismutase activity, glutathione content, malondialdehyde content, and catalase activity test kits were used to detect superoxide dismutase activity, glutathione content, malondialdehyde content, and catalase activity, respectively. Cell apoptosis, intracellular Ca(2+) levels, and mitochondrial membrane potential (Δψ) were detected by flow cytometry. Protein levels were analyzed by Western blotting and immunofluorescence.
  
  
  RESULTS
  S. tridactyla Sch. Bip.-derived polysaccharides and flavones were found to increase the absorbance of MTT, decrease cell death, alleviate the degree of cell edema, restore the cell morphology, reduce cell death fragments and chip phenomenon, increase superoxide dismutase activity, glutathione content, and catalase activity while decreasing the content of malondialdehyde, lowering the population of apoptotic cells, reducing the intracellular Ca(2+) fluorescence, increasing the mitochondrial membrane potential (Δψ), increasing the expressions of p-38, p-53, Bcl-2, and decreasing the expressions of Bax and active-caspase-3.
  
  
  CONCLUSIONS
  S. tridactyla Sch. Bip.-derived polysaccharides and flavones can reduce cell apoptosis to protect HaCaT cells from oxidative damage after UVB irradiation; however, this effect does not occur via the p38MAPK pathway.
authors: Department of Dermatology and Venereology, Affiliated Hospital of Qinghai University, Xining, People's Republic of China.
authors: Yan
authors: Y
authors: Guo
authors: Department of Anatomy, Qinghai University Medical College, Xining, People's Republic of China.
authors: Juan
authors: J
authors: Sun
authors: Department of Dermatology and Venereology, Affiliated Hospital of Qinghai University, Xining, People's Republic of China.
authors: Juan
authors: J
authors: Ye
authors: Department of Dermatology and Venereology, Affiliated Hospital of Qinghai University, Xining, People's Republic of China.
authors: Wenyu
authors: W
authors: Ma
authors: Department of Dermatology and Venereology, Affiliated Hospital of Qinghai University, Xining, People's Republic of China.
authors: Hualing
authors: H
authors: Yan
authors: Department of Dermatology and Venereology, Affiliated Hospital of Qinghai University, Xining, People's Republic of China.
authors: Gang
authors: G
authors: Wang
mesh_terms: D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects; D002118:Calcium / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D047309:Flavones / Q000302:isolation & purification / Q000494:pharmacology*; D005434:Flow Cytometry; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D008315:Malondialdehyde / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects / Q000528:radiation effects; D018384:Oxidative Stress / Q000187:drug effects* / Q000528:radiation effects; D011134:Polysaccharides / Q000302:isolation & purification / Q000494:pharmacology*; D011829:Radiation Dosage; D030441:Saussurea / Q000737:chemistry*; D013482:Superoxide Dismutase / Q000378:metabolism; D014466:Ultraviolet Rays / Q000009:adverse effects; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D047309:Flavones; D011134:Polysaccharides; D008315:Malondialdehyde; D002374:Catalase; D013482:Superoxide Dismutase; D048051:p38 Mitogen-Activated Protein Kinases; D005978:Glutathione; D002118:Calcium
keywords: Saussurea tridactyla Sch. Bip.-derived polysaccharides; flavones; oxidative damage; p38MAPK-independent mechanism