Journal of Oral Tissue Engineering

Influence of Adipocytokines on Differentiation of Pro-osteoblastic Cells

Aiko KAMADA1, Takashi IKEO1, Yoshihiro YOSHIKAWA1, Eisuke DOMAE1, Seiji GODA1, Isao TAMURA1, Hirotaka KON-I2, Joji OKAZAKI3, Akiyo KAWAMOTO3, Yutaka KOMASA3, Isumi TODA4 and Fumihiko SUWA4

1Department of Biochemistry, 2Division for Interdisciplinary Dentistry for Postgraduate Trainee, 3Department of Geriatric Dentistry, 4Department of Anatomy, Osaka Dental University, Osaka, Japan.

J Oral Tissue Engin 2008;6(1): 17-23

Full Text. DOI

Adipocytokines are a group of adipocyte-derived biologically active molecules, including adiponectin, leptin, tumor necrosis factor-α (TNF-α), resistin. A proteolytic cleavage product of adiponectin/Acrp30, gAcrp30, is found to circulate in plasma and to have a three-dimensional structure similar to that of TNF-α. In this study, we demonstrated the expression of adiponectin receptors in cultured pro-osteoblastic cells, and investigated the influences of gAcrp30 and TNF-α on osteoblast differentiation.
RT-PCR analysis demonstrated the expression of transcripts for both adiponectin receptors, AdipoR1 and AdipoR2, in murine pro-osteoblastic cell line, MC3T3-E1. Both gAcrp30 and TNF-α suppressed mRNA levels of type I collagen and RANKL compared with time-matched controls. Interestingly, gAcrp30 had no significant influence on the promotion of osteocalcin expression induced by the stimulation of ascorbic acid and β-glycerophosphate, although TNF-α inhibited the increase of osteocalcin expression.
These results indicated that adiponectin may not affect osteoblast differentiation but may suppress osteoclastogenesis in an endocrine manner, while TNF-α may inhibit the differentiation of pro-osteoblastic cells.

Key words: adiponectin, TNF-α, osteoblast