title: The protective effect of Rhizoma Dioscoreae extract against alveolar bone loss in ovariectomized rats via regulating Wnt and p38 MAPK signaling.
abstract: OBJECTIVE
  The aim of this study was to evaluate the osteoprotective effect of aqueous Rhizoma Dioscoreae extract (RDE) on the alveolar bone of rats with ovariectomy-induced bone loss.
  
  
  METHODS
  Female Wistar rats were subjected to either ovariectomy or a sham operation (SHAM). The ovariectomized (OVX) rats were treated with vehicle (OVX) or RDE by oral gavage or with 17β-estradiol (E2) subcutaneously. After treatments, the bone mineral density (BMD), the three-dimensional bone architecture of the alveolar bone and the plasma biomarkers of bone turnover were analyzed to assess bone metabolism, and the histomorphometry of the alveolar bone was observed. Microarrays were used to evaluate gene expression profiles in alveolar bone from RDE-treated and OVX rats. The differential expression of genes was further analyzed using Ingenuity Pathway Analysis (IPA). The key findings were verified using real-time quantitative RT-PCR (qRT-PCR).
  
  
  RESULTS
  Our results showed that RDE inhibited alveolar bone loss in OVX rats. Compared to the OVX rats, the RDE-treated rats showed upregulated expression levels of 207 genes and downregulated expression levels of 176 genes in the alveolar bone. The IPA showed that several genes had the potential to code for proteins that were involved in the Wnt/β-catenin signaling pathway (Wnt7a, Fzd2, Tcf3, Spp1, Frzb, Sfrp2 and Sfrp4) and the p38 MAPK signaling pathway (Il1rn and Mapk14).
  
  
  CONCLUSIONS
  These experiments revealed that RDE could inhibit ovariectomy-induced alveolar bone loss in rats. The mechanism of this anti-osteopenic effect in alveolar bone may be involved in the reduced abnormal bone remodeling, which is associated with the modulation of the Wnt/β-catenin and the p38 MAPK signaling pathways via gene regulation.
authors.affiliation: Institute of Basic Theory, China Academy of Chinese Medical Sciences, Beijing 100700, China. zzgtcm@163.com.
authors.forename: Zhiguo
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Institute of Basic Theory, China Academy of Chinese Medical Sciences, Beijing 100700, China. xlh891201@sina.com.
authors.forename: Lihua
authors.initials: L
authors.lastname: Xiang
authors.affiliation: Institute of Basic Theory, China Academy of Chinese Medical Sciences, Beijing 100700, China. abai2000_0@163.com.
authors.forename: Dong
authors.initials: D
authors.lastname: Bai
authors.affiliation: Institute of Basic Theory, China Academy of Chinese Medical Sciences, Beijing 100700, China. wangwenlai666@163.com.
authors.forename: Wenlai
authors.initials: W
authors.lastname: Wang
authors.affiliation: Institute of Basic Theory, China Academy of Chinese Medical Sciences, Beijing 100700, China. lei_ruo@163.com.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Institute of Basic Theory, China Academy of Chinese Medical Sciences, Beijing 100700, China. jh-p@163.com.
authors.forename: Jinghua
authors.initials: J
authors.lastname: Pan
authors.affiliation: Institute of Basic Theory, China Academy of Chinese Medical Sciences, Beijing 100700, China. liuhong@163.com.
authors.forename: Hong
authors.initials: H
authors.lastname: Liu
authors.affiliation: Institute of Basic Theory, China Academy of Chinese Medical Sciences, Beijing 100700, China. wangshaojun@163.com.
authors.forename: Shaojun
authors.initials: S
authors.lastname: Wang
authors.affiliation: School of Pharmaceutical Science, Dalian University of Technology, Dalian 116024, China. gxiao@creighton.edu.
authors.forename: Gary Guishan
authors.initials: GG
authors.lastname: Xiao
authors.affiliation: Institute of Basic Theory, China Academy of Chinese Medical Sciences, Beijing 100700, China. judahong@sohu.com.
authors.forename: Dahong
authors.initials: D
authors.lastname: Ju
mesh_terms: D016301:Alveolar Bone Loss / Q000188:drug therapy*; D000818:Animals; D015415:Biomarkers / Q000097:blood; D015519:Bone Density / Q000187:drug effects; D001851:Bone Diseases, Metabolic / Q000188:drug therapy / Q000209:etiology; D016723:Bone Remodeling / Q000187:drug effects; D024042:Collagen Type I / Q000097:blood; D027742:Dioscorea / Q000737:chemistry*; D015536:Down-Regulation; D004958:Estradiol / Q000097:blood / Q000494:pharmacology; D005260:Female; D020935:MAP Kinase Signaling System; D010052:Ovariectomy; D010446:Peptide Fragments / Q000097:blood; D010936:Plant Extracts / Q000494:pharmacology*; D011347:Procollagen / Q000097:blood; D051381:Rats; D017208:Rats, Wistar; D027343:Rhizome / Q000737:chemistry; D015398:Signal Transduction; D015854:Up-Regulation; D051153:Wnt Proteins / Q000235:genetics / Q000378:metabolism; D060449:Wnt Signaling Pathway; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism
chemical_list: D015415:Biomarkers; D024042:Collagen Type I; C495268:Ctnnb1 protein, rat; D010446:Peptide Fragments; D010936:Plant Extracts; D011347:Procollagen; D051153:Wnt Proteins; D051176:beta Catenin; C047202:procollagen Type I N-terminal peptide; D004958:Estradiol; D048051:p38 Mitogen-Activated Protein Kinases