Exploring In Vitro Immunomodulatory Properties of Moss Atrichum undulatum Extracts

Bryophytes are rich sources of diverse secondary metabolites with a wide range of biological activities, including anti-inflammatory, antitumor and antimicrobial effects. The aim of this study was to investigate the chemical composition of extracts from two different genotypes (Serbian and Hungarian) of the axenic moss Atrichum undulatum and evaluate the immunomodulatory potential of the prepared extracts in vitro. Both genotypes of moss samples were cultivated in vitro and subsequently extracted in a Soxhlet apparatus with methanol or ethyl acetate. The highest concentration of total phenolic compounds was found in the methanolic extract of the Serbian genotype (54.25 mg GAE/g extract), while the ethyl acetate extract of the Hungarian genotype showed the highest concentration of phenolic acids (163.20 mg CAE/extract), flavonoids (35.57 mg QE/extract), and flavonols (2.25 mg QE/extract). The extracts showed anti-neuroinflammatory properties by reducing the production of reactive oxygen species, nitric oxide, and tumor necrosis factor alpha by lipopolysaccharide-stimulated microglial cells. Moreover, they mitigated the cytotoxic effects of the pro-inflammatory mediators produced by activated microglia on neurons. The data obtained suggest that extracts from A. undulatum moss have promising anti-neuroinflammatory and neuroprotective properties, making them interesting candidates for further research to combat neuroinflammation.