1: Int Immunopharmacol. 2007 Dec 5;7(12):1497-506. Epub 2007 Jul 17.

Dietary supplementation with laminarin, a fermentable marine beta (1-3) glucan,
protects against hepatotoxicity induced by LPS in rat by modulating immune
response in the hepatic tissue.

Neyrinck AM, Mouson A, Delzenne NM.

Unit of Pharmacokinetics, Metabolism, Nutrition and Toxicology, School of
Pharmacy, Université catholique de Louvain, Brussels, Belgium.

We tested the hypothesis that laminarin (LAM), a beta (1-3) polysaccharide
extracted from brown algae, can modulate the response to a systemic inflammation.
Male Wistar rats (n=7 per group) were fed a standard diet (control) or a diet
supplemented with LAM for 25 days (5% during 4 days followed by 10% during 21
days). Thereafter, Escherichia coli lipopolysaccharides (LPS; 10 mg/kg i.p.) were
injected and the animals were sacrificed 24 h after LPS challenge. The
hypothermia, hyperglycemia and hypertriglyceridemia occurring early after LPS
administration were less pronounced in LAM-treated rats than in controls. The
increase in serum alanine aminotransferase (ALT), aspartate aminotransferase
(AST) and lactate dehydrogenase (LDH) activities - reflecting hepatic alterations
- was lessened after LPS injection in LAM-treated rats compared to control rats. 
LAM treatment decreased serum monocytes number, nitrite (NO(2)) and tumor
necrosis factor-alpha (TNF-alpha). LAM also modulated intra-hepatic immune cells:
it lowered the occurrence of peroxidase-positive cells (corresponding to
monocytes/neutrophils) and, in contrast, it increased the number of ED2-positive 
cells, corresponding to resident hepatic macrophages, i.e. Kupffer cells. In
conclusion, the hepatoprotective effect of marine beta (1-3) glucan during
endotoxic shock may be linked to its immunomodulatory properties. We propose that
both lower recruitment of inflammatory cells inside the liver tissue and lower
secretion of inflammatory mediators play a role in the tissue protective effect
of LAM. These effects could be due to a direct effect of beta-glucan on immune
cells, or to an indirect effect through their dietary fibre properties
(fermentation in the gut).

PMID: 17920526 [PubMed - in process]

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