PUBLICATION

Anthocyanin-enriched polyphenols from Hibiscus syriacus L. (Malvaceae) exert anti-osteoporosis effects by inhibiting GSK-3β and subsequently activating β-catenin

Authors
Karunarathne, W.A.H.M., Molagoda, I.M.N., Lee, K.T., Choi, Y.H., Jin, C.Y., Kim, G.Y.
ID
ZDB-PUB-210831-18
Date
2021
Source
Phytomedicine : international journal of phytotherapy and phytopharmacology   91: 153721 (Journal)
Registered Authors
Keywords
Anthocyanin, GSK-3β, Osteoblast differentiation, Osteogenesis, Osteoporosis, β-catenin
MeSH Terms
  • Animals
  • Anthocyanins*/pharmacology
  • Glycogen Synthase Kinase 3 beta
  • Hibiscus*/chemistry
  • Molecular Docking Simulation
  • Osteoblasts/metabolism
  • Osteogenesis/drug effects*
  • Osteoporosis*/drug therapy
  • Polyphenols*/pharmacology
  • Wnt Signaling Pathway
  • Zebrafish/metabolism
  • beta Catenin/metabolism
PubMed
34461423 Full text @ Phytomedicine
Abstract
The bark and petal of Hibiscus syriacus L. (Malvaceae) have been used to relieve pain in traditional Korean medicine. Recently, we identified anthocyanin-enriched polyphenols from the petal of H. syriacus L. (AHs) and determined its anti-melanogenic, anti-inflammatory, and anti-oxidative properties. Nevertheless, the osteogenic potential of AHs remains unknown.
This study was aimed to investigating the effect of AHs on osteoblast differentiation and osteogenesis in osteoblastic cell lines and zebrafish larvae. Furthermore, we investigated whether AHs ameliorates prednisolone (PDS)-induced osteoporosis.
Cell viability was assessed by cellular morphology, MTT assay, and flow cytometry analysis, and osteoblast differentiation was measured alizarin red staining, alkaline phosphatase (ALP) activity, and osteoblast-specific marker expression. Osteogenic and anti-osteoporotic effects of AHs were determined in zebrafish larvae.
AHs enhanced calcification and ALP activity concomitant with the increased expression of osterix (OSX), runt-related transcription factor 2 (RUNX2), and ALP in MC3T3-E1 preosteoblast and MG-63 osteosarcoma cells. Additionally, AHs accelerated vertebral formation and mineralization in zebrafish larvae, concurrent with the increased expression of OSX, RUNX2a, and ALP. Furthermore, PDS-induced loss of osteogenic activity and vertebral formation were restored by treatment with AHs, accompanied by a significant recovery of calcification, ALP activity, and osteogenic marker expression. Molecular docking studies showed that 16 components in AHs fit to glucagon synthase kinase-3β (GSK-3β); particularly, isovitexin-4'-O-glucoside most strongly binds to the peptide backbone of GSK-3β at GLY47(O), GLY47(N), and ASN361(O), with a binding score of -7.3. Subsequently, AHs phosphorylated GSK-3β at SER9 (an inactive form) and released β-catenin into the nucleus. Pretreatment with FH535, a Wnt/β-catenin inhibitor, significantly inhibited AH-induced vertebral formation in zebrafish larvae.
AHs stimulate osteogenic activities through the inhibition of GSK-3β and subsequent activation of β-catenin, leading to anti-osteoporosis effects.
Genes / Markers
Figures
Show all Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping