The Immunostimulating Role of Lichen Polysaccharides: A Review

Abstract

The immune system has capacity to suppress the development or progression of various malignancies including cancer. Research on the immunomodulating properties of polysaccharides obtained from plants, microorganisms, marine organisms, and fungi is growing rapidly. Among the various potential sources, lichens, symbiotic systems involving a fungus and an alga and/or a cyanobacterium, show promise as a potential source of immunomodulating compounds. It is well known that lichens produce an abundance of structurally diverse polysaccharides. However, only a limited number of studies have explored the immunostimulating properties of lichen polysaccharides. Published studies have shown that some lichen polysaccharides enhance production of nitrous oxide (NO) by macrophages and also alter the production levels of various proinflammatory and antiinflammatory cytokines (IL-10, IL-12, IL-1β, TNF-α, and IFN-α/β) by macrophages and dendritic cells. Although there are only a limited number of studies examining the role of lichen polysaccharides, all results suggest that lichen polysaccharides can induce immunomodulatory responses in macrophages and dendritic cells. Thus, a detailed evaluation of immunomodulatory capacity of lichen polysaccharides could provide a unique opportunity for the discovery of novel therapeutic agents.

Application of immunostimulants in aquaculture: current knowledge and future perspectives

“…Immunostimulants are of great interest in health care and have become one of the most active areas of applied medical research. Immunostimulants, which can promote and induce a strong defence response in the host, include polysaccharides, hormones, vitamins, different components of bacteria, biologically active materials, Chinese herbs and synthetic drugs (Mohapatra, Chakraborty, Kumar, DeBoeck & Mohanta ; Buchmann ; Kasahara & Sutoh ; Song, Beck, Kim, Park, Kim, Kim & Ringø ; Shrestha, St Clair & O’ Neill ; Masahiro ). Immunostimulants are critical in eliciting immune responses capable of providing complete protection against certain pathogens.…”

Lichens as a source of chemical compounds with anti-inflammatory activity

“…The published studies have shown that some lichen polysaccharides demonstrate the anti-inflammatory effect due to alteration of the production levels of various cytokines by macrophages [19]. Omarsdottir et al [20] examined the influence the lichen polysaccharides (Pc-1, Pc-2, Pc-3 and Pc-4, isolated from Peltigera canina) on cytokine production by rat peritoneal macrophages and rat spleen cells.…”

Likenlerin doğal insektisit olarak kullanımı

“…It has been found that some lichens have antitumor activity through components such as polysaccharide, glucan and glycoprotein. Antimicrobial activities against different bacterial species were identified in lichens where many antibiotic substances were detected (Shrestha and St. Clair, 2013;Shrestha et al, 2015).…”