acid-phosphatase and naringin

To discuss the effect of Drynariae Rhizoma's naringin on osteoclasts induced by mouse monocyte RAW264.7.. RAW264.7 cells were induced by 100 μg x L(-1) nuclear factor-κB receptor activator ligand (RANKL) and became mature osteoclasts, which were identified through TRAP specific staining and bone resorption. MTT method was sued to screen and inhibit and the highest concentration of osteoclasts. After being cultured with the screened medium containing naringin for 5 days, positive TRAP cell counting and bone absorption area analysis were adopted to observe the effect of naringin on the formation of osteoclast sells and the bone absorption function. The osteoclast proliferation was measured by flow cytometry. The effects of RANK, TRAP, MMP-9, NFATc1 and C-fos mRNA expressions on nuclear factor-κB were detected by RT-PCR.. Naringin could inhibit osteoclast differentiation, bone absorption function and proliferation activity of osteoclasts, significantly down-regulate RANK, TRAP, MMP-9 and NFATc1 mRNA expressions in the osteoclast differentiation process, and up-regulate the C-fos mRNA expression.. Naringin could inhibit osteoclast differentiation, proliferation and bone absorption function. Its mechanism may be achieved by inhibiting the specific gene expression during the osteoclast differentiation process.

Topics: Acid Phosphatase; Animals; Cell Differentiation; Cell Proliferation; Cells, Cultured; Flavanones; Isoenzymes; Matrix Metalloproteinase 9; Mice; NFATC Transcription Factors; Osteoclasts; Tartrate-Resistant Acid Phosphatase

Wear debris associated periprosthetic osteolysis represents a major pathological process associated with the aseptic loosening of joint prostheses. Naringin is a major flavonoid identified in grapefruit. Studies have shown that naringin possesses many pharmacological properties including effects on bone metabolism. The current study evaluated the influence of naringin on wear debris induced osteoclastic bone resorption both in vitro and in vivo. The osteoclast precursor cell line RAW 264.7 was cultured and stimulated with polymethylmethacrylate (PMMA) particles followed by treatment with naringin at several doses. Tartrate resistant acid phosphatase (TRAP), calcium release, and gene expression profiles of TRAP, cathepsin K, and receptor activator of nuclear factor-kappa B were sequentially evaluated. PMMA challenged murine air pouch and the load bearing tibia titanium pin-implantation mouse models were used to evaluate the effects of naringin in controlling PMMA induced bone resorption. Histological analyses and biomechanical pullout tests were performed following the animal experimentation. The in vitro data clearly demonstrated the inhibitory effects of naringin in PMMA induced osteoclastogenesis. The naringin dose of 10 μg/mL exhibited the most significant influence on the suppression of TRAP activities. Naringin treatment also markedly decreased calcium release in the stimulated cell culture medium. The short-term air pouch mouse study revealed that local injection of naringin ameliorated the PMMA induced inflammatory tissue response and subsequent bone resorption. The long-term tibia pin-implantation mouse model study suggested that daily oral gavage of naringin at 300 mg/kg dosage for 30 days significantly alleviated the periprosthetic bone resorption. A significant increase of periprosthetic bone volume and regaining of the pin stability were found in naringin treated mice. Overall, this study suggests that naringin may serve as a potential therapeutic agent to treat wear debris associated osteolysis.

Topics: Acid Phosphatase; Animals; Bone Resorption; Calcium; Cells, Cultured; Female; Flavanones; Isoenzymes; Mice; Mice, Inbred BALB C; Osteoclasts; Osteogenesis; Osteolysis; Polymethyl Methacrylate; Tartrate-Resistant Acid Phosphatase

Riboflavin-binding protein (RBP) from chicken egg, which was recently reported to be a selective sweet inhibitor for protein sweeteners, was also found to be a bitter inhibitor. RBP elicited broadly tuned inhibition of various bitter substances including quinine-HCl, naringin, theobromine, caffeine, glycyl-L-phenylalanine (Gly-Phe), and denatonium benzoate, whereas several other proteins, such as ovalbumin (OVA) and beta-lactoglobulin, were ineffective in reducing bitterness of these same compounds. Both the bitter tastes of quinine and caffeine were reduced following an oral prerinse with RBP. It was found that RBP binds to quinine but not to caffeine, theobromine, naringin, and Gly-Phe. However, the binding of RBP to quinine was probably not responsible for the bitter inhibition because OVA bound to quinine as well as RBP. Based on these results, it is suggested that the bitter inhibitory effect of RBP is the consequence of its ability to interact with taste receptors rather than because it interacts with the bitter tastants themselves. RBP may have practical uses in reducing bitterness of foods and pharmaceuticals. It may also prove a useful tool in studies of mechanisms of bitter taste.

Topics: Acid Phosphatase; Adult; Caffeine; Dipeptides; Egg White; Egg Yolk; Female; Flavanones; Humans; Lactoglobulins; Male; Membrane Transport Proteins; Ovalbumin; Protein Binding; Quaternary Ammonium Compounds; Quinine; Receptors, G-Protein-Coupled; Serum Albumin, Bovine; Taste; Theobromine