Ethyl Acetate Fraction of Aqueous Extract of Lentinula edodes Inhibits Osteoclastogenesis by Suppressing NFATc1 Expression

Abstract

Bone tissue is continuously remodeled by the coordinated action of osteoclasts and osteoblasts. Nuclear factor-activated T cells c1 (NFATc1) is a well-known transcription factor for osteoclastogenesis and transcriptionally activated by the c-Fos and nuclear factor-kappa B (NF-κB) signaling pathways in response to receptor activation of NF-κB ligand (RANKL). Since excessive RANKL signaling causes an increase of osteoclast formation and bone resorption, inhibition of RANKL or its signaling pathway is an attractive therapeutic approach to the treatment of pathologic bone loss. In this study, we show that an ethyl acetate fraction (LEA) from the shiitake mushroom, Lentinula edodes, inhibited RANKL-induced osteoclast differentiation by blocking the NFATc1 signaling pathway. We found that the water extract and its subsequent ethyl acetate fraction of L. edodes significantly suppressed osteoclast formation. Comparative transcriptome analysis revealed that LEA specifically downregulated a set of RANKL target genes, including Nfatc1. Next, we found that LEA suppresses Nfatc1 expression mainly through the inhibition of the transactivity of p65 and NFATc1. Moreover, treatment of LEA rescued an osteoporotic phenotype in a zebrafish model of glucocorticoid-induced osteoporosis. Collectively, our findings define an undocumented role of the shiitake mushroom extract in regulating bone development.

Transcriptome Analysis Reveals That Abeliophyllum distichum Nakai Extract Inhibits RANKL-Mediated Osteoclastogenensis Mainly through Suppressing Nfatc1 Expression

“…Osteoclast precursor (OCP) cells were generated as described previously [ 18 ]. Briefly, bone marrow cells were isolated from 6–7-week-old ICR male mouse with α-minimum essential medium (α-MEM) supplemented with 10% FBS and M-CSF (5 ng/mL).…”

“…mRNA-Seq reads were aligned to reference mouse genome (mm10 assembly) using TopHat. HOMER program was used to analyze RNA-seq data performed as described [ 18 ]. The cut-off parameters were set at fold change ≥ 2 and FDR < 0.05 (Benjamin-Hochberg).…”

“…Whole-mount skeletal staining on zebrafish larvae was performed as described [ 18 ]. The larvae at 13 dpf were fixed in 10% neutral buffered formalin, and rinsed with tap water several times.…”

Predicting the targets of IRF8 and NFATc1 during osteoclast differentiation using the machine learning method framework cTAP

“…For example, in case of GSE142866 in Table 3 4. Overall, total 16 CPs, 8 CPs for OCU and 8 CPs for OCD, were produced from the 11 studies including GSE111237 [33], GSE142866 [34], GSE149887 [35], GSE152986 [36], GSE17563 [1], GSE20850 [37], GSE30160 , GSE37219 [38], GSE57468 [39], GSE76988 [40], GSE72846 [41] and GSE135479 [42]. As noticeable, some studies include both OCU and OCD cases and some only one type.…”

Fish Models of Induced Osteoporosis

“…Other phenolic compounds, such as tanshinol ( Luo S. et al, 2016 ) and salvianolic acid B ( Luo S. Y. et al, 2016 ), were shown to have bone anabolic properties, and hydroxysafflor yellow A was found to have both bone anabolic and anti-resorptive properties ( Liu L. et al, 2018 ). The ability of alkaloids such as evodiamine ( Yin et al, 2019 ) to trigger bone remodeling and the capacity of fungal extracts—e.g., from shiitake mushroom ( Lee H. et al, 2020 ) and from Penicillium velutinum ( Chen et al, 2018 )—to successfully rescue OP phenotype was successfully demonstrated in the zebrafish GIOP model. Osteoactivity of the TMC formulations Xian-ling-gu-bao ( Wu et al, 2017 ) and Zuogui pill ( Yin et al, 2018 ), commonly used in Asiatic countries to treat primary OP, was also addressed in the zebrafish GIOP model, unveiling their potential to also counteract secondary forms of OP.…”