Inhibition of UV-induced immune suppression and interleukin-10 production by plant oligosaccharides and polysaccharides

• Published in: Photochemistry and photobiology 1999-02, Vol.69 (2), p.141-147
• Main Authors: Strickland, F M, Darvill, A, Albersheim, P, Eberhard, S, Pauly, M, Pelley, R P
• Format: Article
• Language: English
• Subjects: Administration, Topical; Aloe; Animals; Calcium-Calmodulin-Dependent Protein Kinases - metabolism; Carbohydrate Sequence; Female; Glucans; Hypersensitivity, Delayed - immunology; Interleukin-1 - biosynthesis; JNK Mitogen-Activated Protein Kinases; Mice; Mice, Inbred BALB C; Mice, Inbred C3H; Mitogen-Activated Protein Kinases; Molecular Sequence Data; p38 Mitogen-Activated Protein Kinases; Plants, Medicinal; Polysaccharides - pharmacology; Seeds; Skin - drug effects; Skin - radiation effects; T-Lymphocytes - drug effects; T-Lymphocytes - immunology; T-Lymphocytes - radiation effects; Ultraviolet Rays; Xylans
• ISSN: 0031-8655; 1751-1097
• DOI: 10.1562/0031-8655(1999)069<0141:iouiis>2.3.co;2

Application of Aloe barbadensis poly/oligosaccharides to UV-irradiated skin prevents photosuppression of delayed-type hypersensitivity (DTH) responses in mice. We tested the hypothesis that these carbohydrates belong to a family of biologically active, plant-derived polysaccharides that can regulate responses to injury in animal tissues. C3H mice were exposed to 5 kJ/m2 UVB from unfiltered FS40 sunlamps and treated with between 1 pg and 10 micrograms tamarind xyloglucans or control polysaccharides methylcellulose or dextran in saline. The mice were sensitized 3 days later with Candida albicans. Tamarind xyloglucans and purified Aloe poly/oligosaccharides prevented suppression of DTH responses in vivo and reduced the amount of interleukin (IL)-10 observed in UV-irradiated murine epidermis. Tamarind xyloglucans were immunoprotective at low picogram doses. In contrast, the control polysaccharides methylcellulose and dextran had no effect on immune suppression or cutaneous IL-10 at any dose. Tamarind xyloglucans and Aloe poly/oligosaccharides also prevented suppression of immune responses to alloantigen in mice exposed to 30 kJ/m2 UVB radiation. To assess the effect of the carbohydrates on keratinocytes, murine Pam212 cells were exposed to 300 J/m2 UVB radiation and treated for 1 h with tamarind xyloglucans or Aloe poly/oligosaccharides. Treatment of keratinocytes with immunoprotective carbohydrates reduced IL-10 production by approximately 50% compared with the cells treated with UV radiation alone and completely blocked suppressive activity of the culture supernatants in vivo. The tamarind xyloglucans also blocked UV-activated phosphorylation of SAPK/JNK protein but had no effect on p38 phosphorylation. These results indicate that animals, like plants, may use carbohydrates to regulate responses to environmental stimuli.