Molecular Nutrition

Protective effect of β-(1,3 → 1,6)-d-glucan against irritant-induced gastric lesions

Ken-ichiro Tanaka^a1, Yuta Tanaka^a1, Toshio Suzuki^a2 and Tohru Mizushima^a1 c1

^a1 Graduate School of Medical and Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Kumamoto 862-0973, Japan

^a2 Research and Development, Daiso Company Limited, Amagasaki 660-0842, Japan

Abstract

β-(1,3)-d-Glucan with β-(1,6) branches has been reported to have various pharmacological activities, such as anti-tumour and anti-infection activities, which result from its immunomodulating effects. Gastric lesions result from an imbalance between aggressive and defensive factors. In the present study, we examined the effect of β-(1,3)-d-glucan with β-(1,6) branches isolated from Aureobasidium pullulans on the gastric ulcerogenic response in mice. Oral administration of β-glucan ameliorated gastric lesions induced by ethanol (EtOH) or HCl. This administration of β-glucan also suppressed EtOH-induced inflammatory responses, such as infiltration of neutrophils and expression of pro-inflammatory cytokines, chemokines and cell adhesion molecules (CAM) at the gastric mucosa. Of the various defensive factors, the levels of heat shock protein (HSP) 70 and mucin but not PGE₂ were increased by the administration of β-glucan. β-Glucan-dependent induction of the expression of HSP70 and mucin proteins and suppression of the expression of pro-inflammatory cytokines, chemokines and CAM were also observed in cultured cells in vitro. The results of the present study suggest that β-glucan protects the gastric mucosa from the formation of irritant-induced lesions by increasing the levels of defensive factors, such as HSP70 and mucin.

(Received August 17 2010)

(Revised November 18 2010)

(Accepted December 20 2010)

(Online publication March 29 2011)

Key Words:

• β-(1,3 → 1,6)-d-Glucan;
• Gastric lesions;
• Heat shock protein 70;
• Mucin;
• Ethanol

Correspondence:

^c1 Corresponding author: Dr T. Mizushima, email mizu@gpo.kumamoto-u.ac.jp

Footnotes

Abbreviations: CAM, cell adhesion molecule; EtOH, ethanol; HSF1, heat shock factor 1; HSP, heat shock protein; LMW β-glucan, low-molecular-weight β-(1,3 → 1,6)-d-glucan; MPO, myeloperoxidase