title: [Effects of naringin on proliferation, differentiation and maturation of rat calvarial osteoblasts in vitro].
abstract: OBJECTIVE
  To investigate the effects of naringin on the proliferation, differention and maturaion of rat calvarial osteoblasts (ROB).
  
  
  METHODS
  Segregated neonatal SD rat skull, enzyme digestion to obtain ROB. The culture medium was replaced every three days. Serial subcultivation proceeded when cells covered with 80% culture dish. Naringin supplemented into the culture at 1 x 10(-4), 1 x 10(-5), 1 x 10(-6), 1 x 10(-7) mol x L(-1) respectively. MTT method was adopted in proliferation analysis and the activity of ALP was examined after induced 9 days. Search the best concentration and supplemented into the medium, then the osteogenic differentiation markers including the secretion amount of osteocalcin, osteopontin and bone morphogenetic protein-2 were compared between the naringin-supplemented group and the control. Total RNA was isolated and the mRNA level of bFGF, IGF-1, Runx-2, Osterix, ERa and ERbeta was investigated by Real time RT-PCR. Total protein also was isolated and the expression ERa, ERbeta and collagen I was examined by Western blot. After the addition of ICI 182.780, an inhibitor of the estrogen signal pathway, these index also was examined and the changes were compared.
  
  
  RESULTS
  The ROB proliferation was motivated by naringin dose-dependently. And it evidently leads to osteogenic process and maturation. 1 x 10(-5) mol x L(-1) is the best concentration. Naringin improved the secretion of osteocalcin, osteopontin, bone morphogenetic protein-2 and collagen I significantly. Besides, it can also enhanced the mRNA level of bFGF, IGF-1, Runx-2, Osterix, ERalpha and ERbeta. While all these effects can be restrained by ICI 182.780.
  
  
  CONCLUSIONS
  The naringin with final concentration of 1 x 10(-5) mol x L(-1) enhances the osteogenic differentiation and maturation of ROB significantly, while the promoting effects vanished after the addition of ICI 182.780. These results suggesting that naringin is one of the phytoestrogens and have the activity of bone formation may via estrogen signal pathway, it can be developed into a new drug for osteoporosis therapy.
authors.affiliation: Key Laboratory for Space Bioscience and Biotechnology, College of Life Science, Northwestern Polytechnical University, Xi'an 710072, China. zhaiyk1984@163.com
authors.forename: Yuan-Kun
authors.initials: YK
authors.lastname: Zhai
authors.forename: Yin-Bo
authors.initials: YB
authors.lastname: Niu
authors.forename: Ya-Lei
authors.initials: YL
authors.lastname: Pan
authors.forename: Chen-Rui
authors.initials: CR
authors.lastname: Li
authors.forename: Xiang-Long
authors.initials: XL
authors.lastname: Wu
authors.forename: Qi-Bing
authors.initials: QB
authors.lastname: Mei
mesh_terms: D000469:Alkaline Phosphatase / Q000235:genetics / Q000378:metabolism; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D044950:Flavanones / Q000494:pharmacology*; D007334:Insulin-Like Growth Factor I / Q000235:genetics / Q000378:metabolism; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D015675:Osteocalcin / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012886:Skull / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism
chemical_list: D004365:Drugs, Chinese Herbal; D044950:Flavanones; D015675:Osteocalcin; D007334:Insulin-Like Growth Factor I; D000469:Alkaline Phosphatase; C005274:naringin