Intestinal Peyer’s patch-immunomodulating glucomannans from rhizomes of Anemarrhena asphodeloides Bunge

• Published in: Phytochemistry (Oxford) Vol. 96; pp. 337 - 346
• Main Authors: Kiyohara, Hiroaki, Matsuzaki, Toshiake, Yamada, Haruki
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.12.2013
• Subjects: Anemarrhena - chemistry; Anemarrhena asphodeloides Bunge; Animals; beta-mannosidase; Female; fractionation; Humans; immunoglobulin E; interferon-gamma; interleukin-10; Interleukin-6; Intestines - chemistry; Japan; konjac mannan; lymphocytes; Mannans - chemistry; Mannans - isolation & purification; Mannans - pharmacology; medicinal plants; Mice; Mice, Inbred BALB C; oligosaccharides; oral administration; ovalbumin; Peyer's Patches - drug effects; Peyer's Patches - immunology; Peyer’s patches; Plants, Medicinal - chemistry; Plants, Medicinal - drug effects; Rhizome - chemistry; rhizomes; screening; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; β-d-(1 → 4)-Glucomannan; Anemarrhena asphodeloides Bunge; Peyer’s patches; β-d-(1→4)-Glucomannan
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/j.phytochem.2013.09.013

Immunomodulating glucomannans against immunocompetent cells of intestinal Peyer’s patches were isolated from rhizomes of Anemarrhena asphgodeloides, and shown to possess characteristic carbohydrate sequences comprising β-d-Man and β-d-Glc, which are not in the inactive konjac glucomannan. •The crude polysaccharide fraction from Anemarrhena asphgodeloides modulated cytokine production of Peyer’s patch immunocompetent cells.•It also suppressed IgE induction against ingested food antigen.•Glucomannans in the crude polysaccharide fraction were found to be Peyer’s patch-immunomodulating.•Active glucomannans comprised endo-β-d-(1→4)-mannanase-resistant oligosaccharide sequences, and were not in inactive konjac glucomannan. During screening for intestinal Peyer’s patch-immunomodulating polysaccharides from plant resources including medicinal herbs, a potent modulating activity was observed in a crude polysaccharide fraction (AS-1) from the rhizome of Anemarrhena asphodeloides Bunge. Oral administration of AS-1 (100mg/kg/day) to aged BALB/c mice enhanced productions of IL-10, IFN-γ and IL-6 from Peyer’s patch immunocompetent cells, and its oral administration to ovalbumin (OVA)-fed B10.A mice led to significant suppression on induction of OVA-specific IgE in systemic immune system. Further fractionation of the polysaccharides in the crude polysaccharide fraction, AS-1, yielded 4 polysaccharide fractions that were potently active, and contained glucomannans. Treatment of these polysaccharide fractions with endo-β-d-(1→4)-mannanase significantly decreased their activities. Mannanase digestion of the active glucomannan gave both long and short hexosyl-oligosaccharides, whereas konjac glucomannan, which was inactive, released short oligosaccharides. Structural analysis indicates that the long oligosaccharides from the active glucomannan contain mannanase-resistant complex structure comprising β-d-Man and β-d-Glc.