Polysaccharides of Dendrobium officinale inhibit TNF-α-induced apoptosis in A-253 cell line
- 1.1k Downloads
Our previous study demonstrated that polysaccharides of Dendrobium officinale Kimura et Migo (DP) were capable of enhancing immunomodulation in an experimental model of Sjögren’s syndrome, a chronic autoimmune disease mainly affecting the salivary glands. In the present study, we further investigated the protective effect of DP on a human salivary gland cell line A-253 against tumor necrosis factor (TNF)-α-induced apoptosis.
TNF-α (100 U/ml) was used as the stimulus for treating the A-253 cells to induce cellular apoptosis. Nuclear factor-kappa B (NF-κB, p65), phosphorylation of mitogen-activated protein kinases (MAPK), reactive oxygen species (ROS) generation, mitochondrial membrane potential and proapoptotic proteins were examined. A-253 cells were pre-treated with DP for 12 h before TNF-α stimulation.
We observed translocation of NF-κB into the nuclei, prolonged MAPK, excessive ROS generation and strongly decreased mitochondrial membrane potential, and subsequently cytochrome C release and caspase-3 activation. However, pre-treatment with DP significantly inhibited the TNF-α-induced apoptotic factors.
Our data suggested the inhibitory effect of DP on TNF-α-induced apoptosis in a human salivary gland cell line. This inhibition indicated potential inference of DP in the initial plasma membrane-bound complex of TNF-α and its receptors.
KeywordsTNF-α A-253 Polysaccharides Dendrobium officinale Apoptosis
This work was supported by grants (Project No. 20730472 and Project No. 201011159206) from the University of Hong Kong.
- 4.Yukawa T, Ohba H, Cameron K, Chase M (1996) Chloroplast DNA phylogeny of subtribe Dendrobiinae (Orchidaceae): Insights from a combined analysis based on rbcL sequences and restriction site variation. J Plant Res 109:169–176.Google Scholar
- 8.Lin X, Sze SC-W, Tong Y, Zhang Z, Feng Y, Chen JP, et al. Protective effect of Dendrobium officinale polysaccharides on experimental Sjogren’s syndrome. J Compl Integr Med. 2010;7:1–14.Google Scholar
- 44.Vanden Berghe W, Plaisance S, Boone E, De Bosscher K, Schmitz ML, Fiers W, et al. p38 and extracellular signal-regulated kinase mitogen-activated protein kinase pathways are required for nuclear factor-kappaB p65 transactivation mediated by tumor necrosis factor. J Biol Chem. 1998;273:3285–90.PubMedCrossRefGoogle Scholar
- 45.Van Lint J, Agostinis P, Vandevoorde V, Haegeman G, Fiers W, Merlevede W, et al. Tumor necrosis factor stimulates multiple serine/threonine protein kinases in Swiss 3T3 and L929 cells. Implication of casein kinase-2 and extracellular signal-regulated kinases in the tumor necrosis factor signal transduction pathway. J Biol Chem. 1992;267:25916–21.PubMedGoogle Scholar