Anti-Inflammatory Activity of the Wild Mushroom, Echinodontium tinctorium, in RAW264.7 Macrophage Cells and Mouse Microcirculation

Abstract

The aim of this study was to investigate the anti-inflammatory activity of a previously un-studied wild mushroom, Echinodontium tinctorium, collected from the forests of north-central British Columbia. The lipopolysaccharide (LPS)-induced RAW264.7 macrophage model was used to study the in vitro anti-inflammatory activity. The crude alkaline extract demonstrated potent anti-inflammatory activity, and was further purified using a “bio-activity-guided-purification” approach. The size-exclusion and ion-exchange chromatography yielded a water-soluble anti-inflammatory polysaccharide (AIPetinc). AIPetinc has an average molecular weight of 5 kDa, and is a heteroglucan composed of mainly glucose (88.6%) with a small amount of galactose (4.0%), mannose (4.4%), fucose (0.7%), and xylose (2.3%). In in vivo settings, AIPetinc restored the histamine-induced inflammatory event in mouse gluteus maximus muscle, thus confirming its anti-inflammatory activity in an animal model. This study constitutes the first report on the bioactivity of Echinodontium tinctorium, and highlights the potential medicinal benefits of fungi from the wild forests of northern British Columbia. Furthermore, it also reiterates the need to explore natural resources for alternative treatment to modern world diseases.

Medicinal Properties and Bioactive Compounds from Wild Mushrooms Native to North America

“…Whether it be Hericium sp. which is found growing on hardwood and coniferous trees that contains a number of small molecules with antibacterial properties [ 17 ] or Echinodontium tinctorium which is native to BC commonly found growing as a woody conk on true firs with anti-inflammatory compound in its fruiting bodies [ 18 ]. Others include Cortinarius armillatus which grows in moist coniferous forests and contains orellanine, a potential toxin against renal carcinoma [ 19 , 20 ].…”

“…Some of the important medicinal benefits reported include antimicrobial, antioxidant, anticancer, immune system enhancer, antiviral, anti-hyperlipidemia, radical scavenger, anti-parasitic and anti-inflammatory [ 42 ]. Amongst these, the most common medicinal properties reported from mushrooms native to North America are anti-cancer, immuno-stimulatory, anti-inflammatory, antimicrobial and antioxidant as shown in Table 1 [ 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 41 ].…”

“…A limited number of anti-inflammatory compounds have been isolated from mushrooms native to North America. A 5 kDa polysaccharide isolated from the NaOH extract of North American mushroom E. tinctorium was able to induce anti-inflammatory response in Raw264.7 macrophage cells [ 18 ]. A polysaccharide called CDP from Gymnopus dryophilus [ 31 ], and CDP-like polysaccharides from L. edodes and Marasmius oreades [ 32 ], can inhibit nitric oxide production in Raw264.7 macrophage cells.…”

“…Currently, there are very limited studies examining the anti-inflammatory potential of North American mushrooms using animal models. In one study, the polysaccharide AIPetinc isolated from E. tinctorium showed anti-inflammatory activity on histamine-induced inflammatory mouse microcirculation model ( n = 10 mice) [ 18 ]. An intra-vital mouse model was used to determine acetylcholine-induced vasodilation, which is one of the events in inflammation.…”

Editorial to Special Issue—Anti-Inflammatory Activity of Natural Products

“…Not only plants may possess anti-inflammatory properties, wild mushrooms, such as Echinodontium tinctorium, also was reported as possessing this activity [20]. A water soluble polysaccharide (AIPetinc) obtained from this mushroom with an average molecular weight of 5kDa and mainly constituted by glucose and with small percentages of galactose, mannose, fucose and xylose was able to restore the histamine-induced inflammatory process in mouse gluteus maximus muscle [20].…”