Planta Med 2008; 74 - PA182
DOI: 10.1055/s-0028-1084180

Stimulation of TNF- α secretion by Polysaccharide Krestin, a Trametes versicolor mushroom extract, is toll-like receptor 4-dependent and dectin-1 independent

L Price 1, C Wenner 1, D Sloper 2, J Slaton 2, J Novack 1
  • 1Bastyr University, Department of Basic Sciences, School of Natural Health Sciences, Kenmore, WA 98028, United States
  • 2Department of Urologic Surgery, University of Minnesota, Minneapolis MN 55455, United States, University of Minnesota Minneapolis, MN Veterans Administration Medical Center Minneapolis, MN 55417, United States

The effects of mycological extracts on inflammatory cytokine secretion in J774A.1 mouse macrophage cell cultures (wild type peritoneal macrophages and TLR4-deficient mice (C57B1/6 TLR4 (-/-)) involving the pathogen-associated molecular pattern recognition (PAMP) receptors TLR-4 and dectin-1 were investigated [1]. Trametes versicolor extract Polysaccharide Krestin (PSK), an extract from Ganoderma lucidum, also known as Reishi, or the secreted polysaccharide scleroglucan from Sclerotium rolfsi all induced TNF-α secretion in J774A.1 cell cultures. TLR-4 blocking antibodies inhibited PSK- and Reishi-induced TNF-α secretion, but not scleroglucan-induced secretion in both J774A.1 cells and primary splenocytes from C57Bl/6 mice. Conversely, dectin-1 blocking antibody inhibited scleroglucan- but not PSK- and Reishi-induced TNF-α secretion. PSK induced TNF-α and IL-6 secretion in wild type but not in TLR4 deficient macrophages (C57B1/6TLR4-/-). Thus, PSK requires TLR-4 receptors for induction of TNF-α and IL-6 inflammatory cytokines, similar to reported Reishi polysaccharide effects [2]. The receptor-mediated differences in signaling for TNF-α secretion between scleroglucan, PSK and Reishi mushroom extracts may be due to conformational differences in β-D-glucans and/or other non-glucan constituents that can activate TLR-4.

References: 1. Werling, D. et al (2003) Vet. Immunol. Immunopathol. 91:1–12

2. Hsu, HY et al. (2004)J. of Immun. 173:5989–5999