Flavonoids are the active component of the Herba Epimedii (H. Epimedii), which is commonly used in Asia. This study is to investigate the effect of H. Epimedii on bone repair after anti-infection treatment in vivo. The bioactive-composition group of H. Epimedii (BCGE) contained four flavonoids with the total content of 43.34%. Rabbits with chronic osteomyelitis in response to injection with Staphylococcus aureus were treated with BCGE of 242.70 mg/kg/day intragastrically after vancomycin-calcium sulphate treatment. Micro-computerd tomography (CT), morphology, blood biochemistry and osteocalcin levels were assessed for effect evaluation. In addition, the rat calvarial osteoblasts infected with S. aureus were treated with vancomycin and BCGE. Cell viability, alkaline phosphatase activity, bone morphogenetic protein 2, Runt-related transcription factor 2, osteoprotegerin, receptor activator of nuclear factor-κB ligand mRNA levels and protein expression were assessed. Our results indicated that BCGE promoted bone repair via increasing the bone mass, the volume of bone, promoting osteocalcin secretion after vancomycin-calcium sulfate treatment. BCGE enhanced the cell proliferation, by regulating bone morphogenetic protein 2, runt-related transcription factor 2, and osteoprotegerin/receptor activator of nuclear factor κ-B ligand mRNA and protein expression to maintain the balance between bone formation and bone resorption. Therefore, BCGE is a potential adjuvant herbal remedy for the post-infection treatment of chronic osteomyelitis. Copyright © 2016 John Wiley & Sons, Ltd.

Vancomycin is an effective antibiotic for treatment of bone infection caused by Staphylococcus aureus, however, a high local concentration of vancomycin might induce a delay in bone union. Icariin has been reported to suppress osteoclastogenes and promote osteogenesis. Our study aimed to investigate the effect of icariin on bone repair after anti-infection treatment in vivo and to explore the resisting effect of icariin on rat calvarial osteoblasts (ROBs) inhibited with high doses of vancomycin. Rabbits with bone infection of S. aureus were treated with implanted vancomycin-calcium sulfate (VCS) and icariin at 10.86 mg/kg/day for consecutive 8 weeks. Micro-CT, morphology, blood biochemistry were evaluated. In addition, ROBs were treated with vancomycin and icariin at different doses. Cell proliferation and differentiation capabilities, BMP2, Runx2, OPG, RANKL mRNA levels and protein expression were assessed. The results indicated that high dose of vancomycin significantly decreased bone mass and inhibited osteocalcin secretion; icariin increased these indicators compared with the single vancomycin treatment. Over 0.1 mg/mL of vancomycin inhibited the proliferation and differentiation of ROBs, while icariin resisted the inhibition of vancomycin by regulating cell cycle and promoting the Alkaline phosphatase (ALP) activity. Moreover, icariin promote bone formation by up-regulating BMP2/Runx2 and OPG/RANKL pathways. Icariin exhibited osteoplastic properties on osteoblasts that had been inhibited with high doses of vancomycin. Therefore, icariin is helpful for post-infection treatment of bone infection.

No abstract

Chronic osteomyelitis is primarily caused by infection with Staphylococcus aureus (S. aureus). Antibiotics are commonly administered; however, it is a challenge to promote bone healing. The aim of this study was to investigate the in vitro effects of alkaloids from the herbal remedy Sophora flavescens (ASF) on rat calvarial osteoblasts (ROBs) infected with S. aureus and healthy osteoclasts. Cell proliferation and alkaline phosphatase, interleukin-6, and tumour necrosis factor-α activity was measured in infected ROBs; tartrate-resistant acid phosphatase was evaluated in osteoclasts via enzyme-linked immunosorbent assay. The mRNA and protein expression levels of bone morphogenetic protein 2, runt-related transcription factor 2, osteoprotegerin, and receptor activator of nuclear factor kappa-B ligand were assessed in infected ROBs through reverse transcription-polymerase chain reaction and western blotting analysis, respectively. Results indicated that ASF increased the viability of uninfected ROBs and infected ROBs treated with vancomycin via regulation of bone morphogenetic protein 2, runt-related transcription factor, osteoprotegerin, and receptor activator of nuclear factor kappa-B ligand mRNA and protein expression levels. In addition, the secretion of the inflammatory factor tumour necrosis factor-α was decreased and alkaline phosphatase activity was increased, inhibiting the viability of osteoclasts and tartrate-resistant acid phosphatase activity. Therefore, the herbal remedy ASF has potential as a new treatment for chronic osteomyelitis.

Two new triterpenoid saponins, namely caraganoside C (1) and caraganoside D (2), were isolated from the seeds of Caragana microphylla. Their structures were elucidated on the basis of spectroscopic analyses, including homo- and hetero-nuclear correlation NMR experiments (COSY, HSQC and HMBC). Both 1 and 2 exhibited moderate inhibitory activity against NO production in LPS-stimulated RAW264.7 cells with IC(50) values of 26.4 μM and 32.2 μM, respectively. In addition, 1 showed weak cytotoxicity against MCF-7, HL-60, HCT116, and A549 cell lines.