Research advances in the structures and biological activities of secondary metabolites from Talaromyces

The genus Talaromyces belongs to the phylum Ascomycota of the kingdom Fungi. Studies have shown that Talaromyces species yield many kinds of secondary metabolites, including esters, terpenes, steroids, alkaloids, polyketides, and anthraquinones, some of which have biological activities such as anti-inflammatory, bacteriostatic, and antitumor activities. The chemical constituents of fungi belonging to the genus Talaromyces that have been studied by researchers over the past several years, as well as their biological activities, are reviewed here to provide a reference for the development of high-value natural products and innovative uses of these resources.

N-Acetyldopamine Dimer Attenuates DSS-Induced Ulcerative Colitis by Suppressing NF-κB and MAPK Pathways

Ulcerative Colitis (UC) is a major form of chronic inflammatory bowel disease of the colonic mucosa and exhibits progressive morbidity. There is still a substantial need of small molecules with greater efficacy and safety for UC treatment. Here, we report a N-acetyldopamine dimer (NADD) elucidated (2R,3S)-2-(3′,4′-dihydroxyphenyl)-3-acetylamino-7-(N-acetyl-2″-aminoethyl)-1,4-benzodioxane, which is derived from traditional Chinese medicine Isaria cicadae, exhibits significant therapeutic efficacy against dextran sulfate sodium (DSS)-induced UC. Functionally, NADD treatment effectively relieves UC symptoms, including weight loss, colon length shortening, colonic tissue damage and expression of pro-inflammatory factors in pre-clinical models. Mechanistically, NADD treatment significantly inhibits the expression of genes in inflammation related NF-κB and MAPK signaling pathways by transcriptome analysis and western blot, which indicates that NADD inhibits the inflammation in UC might through these two pathways. Overall, this study identifies an effective small molecule for UC therapy.

Aureonitol Analogues and Orsellinic Acid Esters Isolated from Chaetomium elatum and Their Antineuroinflammatory Activity

Overexpression of various pro-inflammatory factors in microglial cells tends to induce neurodegenerative diseases, for which there is no effective therapy available. Aureonitol (1) and seven analogues, including six previously undescribed [elatumenol A-F (2-4, 6-8, respectively)], along with two new orsellinic acid esters [elatumone A and B (9 and 10)], were isolated from Chaetomium elatum. The structures of the compounds were established through comprehensive analysis of spectroscopic data, including high-resolution mass spectra and one- and two-dimensional NMR, and absolute configurations determined by the Mosher method, dimolybdenum tetraacetate-induced circular dichroism, and theoretical calculations including electronic circular dichroism and NMR. Metabolites 3, 4, 7, and 8 exhibited antineuroinflammatory activity by attenuating the production of inflammatory mediators, such as nitric oxide, interleukin-6, interleukin-1β, tumor necrosis factor-α, and reactive oxygen species. Western blot results indicated 8 decreases the level of inducible nitric oxide synthase and cyclooxygenase-2 and suppresses the expression of Toll-like receptor 4 and nuclear factor kappa-B (NF-κB) as well as the phosphorylation of the inhibitor of NF-κB and p38 mitogen-activated protein kinases in lipopolysaccharide-activated BV-2 microglial cells.