Reagents and animals

LPS, MPS, and PDTC were purchased from Sigma–Aldrich (St. Louis, MO, USA). Antibodies of TLR4, total NF-κB-p65, anti-OPG, anti-Runx2, PPARγ, and anti glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were obtained from Cell Signaling Technology, Inc.(Danvers, MA, USA). The enzyme-linked immunosorbent assay (ELISA) kits for the determination of IL-6, IL-10, and TNF-α were produced by Nanjing KeyGEN Biotech. Co., Ltd. (Nanjing, China). NFATc1,Wnt3a, and β-catenin antibody and isotype IgG control antibody were obtained from Santa Cruz Biotechnology(Santa Cruz, CA, USA).

Eighty adult male Sprague–Dawley (SD) rats (aged 10–12 weeks, weighing 270–330 g) were purchased from the Experimental Animals Center of Xi’an Jiaotong University. All rats were housed in a light controlled environment (12 h light–dark cycles) under standard temperature (22 ± 3 °C) and a relatively suitable humidity (50% ± 15%). The environment was also equipped with an air-filtering system. The cages and water were sterilized, and the animals were allowed activity freely. Standard rodent chow and water ad libitum were provided. All animal experiment procedures were approved under the guidelines of the Laboratory Animal Research Committee and conducted in accordance with the accepted policies of our university and Chinese animal care authorities, in addition to the National Institute of Health Guide for the Care and Use of Laboratory Animals.