Erinacine C Activates Transcription from a Consensus ETS DNA Binding Site in Astrocytic Cells in Addition to NGF Induction

Abstract

Medicinal mushrooms of the genus Hericium are known to produce secondary metabolites with homeostatic properties for the central nervous system. We and others have recently demonstrated that among these metabolites cyathane diterpenoids and in particular erinacine C possess potent neurotrophin inducing properties in astrocytic cells. Yet, the signaling events downstream of erinacine C induced neurotrophin acitivity in neural-like adrenal phaeochromocytoma cells (PC12) cells have remained elusive. Similar, signaling events activated by erinacine C in astrocytic cells are unknown. Using a combination of genetic and pharmacological inhibitors we show that erinacine C induced neurotrophic activity mediates PC12 cell differentiation via the TrkA receptor and likely its associated PLCγ-, PI3K-, and MAPK/ERK pathways. Furthermore, a small library of transcriptional activation reporters revealed that erinacine C induces transcriptional activation mediated by DNA consensus binding sites of selected conserved transcription factor families. Among these, transcription is activated from an ETS consensus in a concentration dependent manner. Interestingly, induced ETS-consensus transcription occurs in parallel and independent of neurotrophin induction. This finding helps to explain the many pleiotropic functions of cyathane diterpenoids. Moreover, our studies provide genetic access to cyathane diterpenoid functions in astrocytic cells and help to mechanistically understand the action of cyathanes in glial cells.

Neurotrophic and immunomodulatory lanostane triterpenoids from wood-inhabiting Basidiomycota

“…According to [23], cyathane diterpenes isolated from the submerged cultures of H. erinaceus and H. flagellum were found to act on 1321N1 cells by increasing the transcription of either bdnf or ngf . Similarly, a study by [11] reported that erinacine C influenced the expression in these astrocytic cells on the transcriptional level, probably including also factors that regulate ngf expression. In the present study, we clearly demonstrated that the triterpenoids increases ngf and bdnf synthesis in 1321N1 cells.…”

“…As control, serum-reduced medium supplemented with 0.5% DMSO was used. Cells were incubated for 48 h [11,23]. Total RNA was extracted using the NucleoSpin R RNA Plus kit (Macherey-Nagel GmbH& Co KG, Germany) followed by further purification (NucleoSpin R RNA Clean-up kit) according to the manufacturer’s protocol.…”

“…BIO- 72005 (Bioline)). The following PCR primers were used for amplifying specific cDNA fragments: gapdh (sense 5’-ACCACAGTCCATGCCATCAC-3’; antisense: 5‘- TCCACCACCCTGTTGCTGTA-3’ 451 bp), ngf (sense: 5‘- CCAAGGGAGCAGTTTCTATCCTGG-3’; antisense 5‘- GGCAGTTGTCAAGGGAATGCTGAAGTT-3’ 189 bp) and bdnf (sense: 5’- TAACGGCGGCAGACAAAAAGA-3’; antisense: 5’-GAAGTATTGCTTCAGTTGGCCT-3‘; 101 bp) [11]. The PCR reactions were performed in a 10 μL volume containing cDNA template (2 μL), SensiFast ™ SYBR No-Rox One-step Mix (5 μL), primers (400 nM; 0.4 μL), Reverse transcriptase (0.1 μL), RiboSafe RNase Inhibitor (0.2 μL) and Rnase free water (1.9 μL).…”

“…The metabolites from Antrodia sp. MUCL 56049 included tumulosic acid or (3β,16α)dihydroxy-24-methylenelanost-8-en-21-oic acid (8) [18], polyporenic acid C or 16α-hydroxy-24-methylene-3-oxolanosta-7,9(11)-dien-21-oic acid (9) [19], 16α-hydroxyeburiconic acid or16α -hydroxy-24-methylene-3-oxolanost-8-en-21-oic acid (10) [19], dehydrotumulosic acid or (3β,16α)-dihydroxy-24-methylene-lanosta-7,9(11)-dien-21-oic acid (11) [20], and pachymic acid or 3β-acetyloxy-16α-hydroxy-24-methylene-lanost-8-en-21-oic acid (12) [21].…”

“…These metabolites are preferred due to the ability to stimulate the production of neurotrophins, in addition to exerting antioxidative and anti-inflammatory properties, which provides neuroprotective action. Several studies showed that metabolites from Hericium erinaceus demonstrated neuritogenic properties in neuronal cells, which may be useful in the management of NDDs [6,11].…”