Flavonoids of HerbaEpimediiEnhances Bone Repair in a Rabbit Model of Chronic Osteomyelitis During Post-infection Treatment and Stimulates Osteoblast Proliferation inVitro

Application of hydrophobic eutectic solvent in efficient biotransformation of total flavonoids of Herba Epimedii

Icaritin, a hydrolysate from total flavonoids of Epimedii (TFE), which has better anti-hepatoma activity than its glycosylated form. In this work, immobilized enzymes 4LP-Tpebgl3@Na-Y and DtRha@ES-107 were used to hydrolyze TFE to prepare icaritin. Five different hydrophobic deep eutectic solvents (HDES) were prepared and the most ideal HDES was successfully selected, which was composed of dodecyl alcohol and thymol with the molar ratio of 2:1. The relative enzyme activity of 4LP-Tpebgl3@Na-Y and DtRha@ES-107 was about 102.4 % and 112.5 %, respectively. In addition, the thermal and binding stability of 4LP-Tpebgl3@Na-Y and DtRha@ES-107 in HDES was not affected negatively. In the biphasic system composed of 50 % (v/v) HDES and Na2HPO4-citric acid buffer (50 mM, pH 5.5), 4LP-Tpebgl3@Na-Y (1.0 U/mL) and TFE (1 g/L) were reacted at 80 °C for 1 h, and then reacted with DtRha@ES-107 (20 U/mL) at 80 °C for 2 h. Finally, TFE was completely converted to 301.8 mg/L icaritin (0.82 mM). After 10 cycles, 4LP-Tpebgl3@Na-Y/DtRha@ES-107 still maintained 84.1 % original activity. In this study, we developed an efficient methodology for icaritin preparation through the integration of enzymatic catalysis and adsorption separation, presenting a viable approach for large-scale, cost-effective production of icaritin.

Epimedium-Curculigo herb pair enhances bone repair with infected bone defects and regulates osteoblasts through LncRNA MALAT1/miR-34a-5p/SMAD2 axis

Infected bone defects (IBDs) are the common condition in the clinical practice of orthopaedics. Although surgery and anti-infective medicine are the firstly chosen treatments, in many cases, patients experience a prolonged bone union process after anti-infective treatment. Epimedium-Curculigo herb pair (ECP) has been proved to be effective for bone repair. However, the mechanisms of ECP in IBDs are insufficiency. In this study, Effect of ECP in IBDs was verified by micro-CT and histological examination. Qualitative and quantitative analysis of the main components in ECP containing medicated serum (ECP-CS) were performed. The network pharmacological approaches were then applied to predict potential pathways for ECP associated with bone repair. In addition, the mechanism of ECP regulating LncRNA MALAT1/miRNA-34a-5p/SMAD2 signalling axis was evaluated by molecular biology experiments. In vivo experiments indicated that ECP could significantly promote bone repair. The results of the chemical components analysis and the pathway identification revealed that TGF-β signalling pathway was related to ECP. The results of in vitro experiments indicated that ECP-CS could reverse the damage caused by LPS through inhibiting the expressions of LncRNA MALAT1 and SMAD2, and improving the expressions of miR-34a-5p, ALP, RUNX2 and Collagen type І in osteoblasts significantly. This research showed that ECP could regulate the TGF-β/SMADs signalling pathway to promote bone repair. Meanwhile, ECP could alleviate LPS-induced bone loss by modulating the signalling axis of LncRNA MALAT1/miRNA-34a-5p/ SMAD2 in IBDs.

Unveiling the Therapeutic Potential of Herba Epimedii: Enhancing Bone Healing Through Cytoskeletal Regulation of RhoA/Rock1 Pathway

Herba Epimedii is widely used to promote bone healing, and their active ingredients are total flavonoids of Epimedium (TFE). Ras homolog gene family member A / Rho-associated protein kinase (RhoA/Rock), an important pathway regulating the cytoskeleton, has been proven to affect bone formation. However, whether TFE promotes bone healing via this pathway remains unclear. In this study, the therapeutic effects of TFE were estimated using micro-computed tomography and hematoxylin and eosin staining of pathological sections. F-actin in osteoblasts was stained to investigate the protective effects of TFE on the cytoskeleton. Its regulatory effects on the RhoA/Rock1 pathway were explored using RT-qPCR and Western blot analysis. Besides, flow cytometry, alkaline phosphatase and nodule calcification staining were performed to evaluate the effects on osteogenesis. The bone healing in rats was improved, the cytoskeletal damage in osteoblasts was reduced, the RhoA/Rock1 pathway was downregulated, and osteogenesis was enhanced after TFE treatment. Thus, TFE can promote bone formation at least partially by regulating the expression of key genes and proteins in the cytoskeleton. The findings of this study provided evidence for clinical applications and would contribute to a better understanding of Epimedium's mechanisms in treating bone defects.

A systematic review of traditional uses, phytochemistry, pharmacology and toxicity of Epimedium koreanum Nakai

ETHNOPHARMACOLOGICAL RELEVANCE

Epimedium koreanum Nakai (E. koreanum), a member of the genus Epimedium in the family Berberidaceae, is a well-known and well-liked traditional herb used as a "kidney tonic". For thousands of years, it has been utilized for renal yang deficiency, impotence, spermatorrhea, impotence, weakness of tendons and bones, rheumatic paralysis and discomfort, numbness, and constriction.

AIM OF THE STUDY

The paper aims to comprehensively in-depth, and methodically review the most recent research on the traditional uses, phytochemistry, pharmacology, and toxicity of E. koreanum.

MATERIALS AND METHODS

Scientific databases including Web of Science, PubMed, Google Scholar, Elsevier, Springer, ScienceDirect, Baidu Scholar, and CNKI and medicine books in China were searched for relevant information on E. koreanum.

RESULTS

In traditional uses, E. koreanum is frequently used to treat various diseases like erectile dysfunction, infertility, rheumatoid arthritis, osteoporosis, asthma, kidney-yang deficiency syndrome, etc. To date, more than 379 compounds have been discovered from various parts of E. koreanum, including flavonoids, lignans, organic acids, terpenoids, hydrocarbons, dihydrophenanthrene derivatives, alkaloids, and others. Research has revealed that the compounds and crude extracts have a wide range of pharmacological effects on the reproductive, cardiovascular, and nervous systems, as well as anti-osteoporosis, anti-tumor, antioxidant, anti-inflammatory, immunomodulatory, hepatoprotective, and antiviral properties. Besides, the crude extracts show potential hepatotoxicity.

CONCLUSION

Based on recent domestic and international research investigations, E. koreanum contains a wealth of chemical components with pronounced pharmacological activities. Its traditional uses are numerous, and the majority of these traditional uses have been supported by contemporary pharmacological investigations. Crude extracts, on the other hand, can result in hepatotoxicity. Therefore, additional in vivo and in vitro experimental research on the pharmacology and toxicology of E. koreanum are required in the future to assess its safety and efficacy. This will give a firmer scientific foundation for its safe application and the development of new drugs in the future.

Injectable rBMSCs-laden hydrogel microspheres loaded with naringin for osteomyelitis treatment

Osteomyelitis, caused by purulent bacteria invading bone tissue, often occurs in long bones and seriously affects the physical and mental health and working ability of patients; it can even endanger life. However, due to bone cavity structure, osteomyelitis tends to occur inside the bone and thus lacks an effective treatment; anti-inflammatory treatment and repair of bone defects are necessary. Here, we developed injectable hydrogel microspheres loaded with naringin and bone marrow mesenchymal stem cells, which have anti-inflammatory and osteogenic properties. These homogeneous microspheres, ranging from 200 to 1000μm, can be rapidly fabricated using an electro-assisted bio-fabrication method. Interestingly, it was found that microspheres with relatively small diameters (200μm) were more conducive to the initial cell attachment, growth, spread, and later osteogenic differentiation. The developed microspheres can effectively treat tibial osteomyelitis in rats within six weeks, proving their prospects for clinical application.

Network Pharmacology-Based Analysis on Lonicera japonica for Chronic Osteomyelitis Treatment

MATERIALS AND METHODS

Active compounds of LJP were examined established on the analysis platform, Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. DrugBank identified drug targets and annotated them on UniPort and GeneCards. Besides, the COM-related genes were identified on GeneCards. The network of the drug, main active compounds, targets, and diseases was built utilizing Cytoscape. STRING was utilized to build the protein-protein interaction network. Moreover, the KEGG and GO pathway enrichment analysis were applied to analyze biological function.

RESULTS

23 active compounds of LJP were screened, and 204 drug targets and 686 COM-related genes were identified. Forty-five intersection genes were overlapped from 204 drug targets and 686 COM-related genes. The drug-active compounds-target protein-diseases network was established based on 23 active compounds of LJP and 45 intersection genes. Moreover, the interaction of 45 intersection genes was explored by the PPI network, and the drug-active compounds-target protein-diseases network was formed grounded by 23 active compounds of LJP, 45 intersection genes, and PPI network. The KEGG and GO pathway enrichment analysis specified that 45 intersection genes primarily enriched in immune-related pathways and oxidative stress-related pathways.

CONCLUSIONS

In the research done, the main active compounds of LJP and drug targets in the treatment of COM were identified. Our findings might provide the ingredient option of LJP and drug targets of LJP in COM treatment.

MRI Manifestations and Diagnostic Value of Chronic Osteomyelitis

If chronic osteomyelitis is not treated promptly and thoroughly, the wound will not heal for a long time, and the affected limb will be dysfunctional or disabled. In severe cases, it may even require amputation. In this article, a total of 50 patients with chronic osteomyelitis who meet the inclusion criteria were selected from January 2019 to March 2020 and were divided into two groups based on patient compliance, namely, a treatment group and a control group. The results of this group of studies showed that osteomyelitis is mostly manifested as limited diffusion, showing high signal on DWI, and ADC value is significantly higher than that of normal bone area. The normal bone area did not show obvious focal abnormal signals on the conventional MRI image. The ADC value of the measured patient's osteomyelitis area was compared with the ADC value of the normal bone area. The ADC value was significantly higher than that of the normal bone area, and the difference was statistically significant. Studies have shown that membrane induction technology is superior to the bone handling group in terms of limb function scores and results satisfaction in the treatment of chronic osteomyelitis bone defects. Membrane induction technology has a low complication rate, a small number of X-ray examinations, a short healing time, and a high functional score. However, bone handling technology has a long treatment process, long fixation time and healing time, nail channel infection, joint stiffness, nerve damage, and many other complications.

Anti-Inflammatory and Chondroprotective Effects of Vanillic Acid and Epimedin C in Human Osteoarthritic Chondrocytes

In osteoarthritis (OA), inhibition of excessively expressed pro-inflammatory cytokines in the OA joint and increasing the anabolism for cartilage regeneration are necessary. In this ex-vivo study, we used an inflammatory model of human OA chondrocytes microtissues, consisting of treatment with cytokines (interleukin 1β (IL-1β)/tumor necrosis factor α (TNF-α)) with or without supplementation of six herbal compounds with previously identified chondroprotective effect. The compounds were assessed for their capacity to modulate the key catabolic and anabolic factors using several molecular analyses. We selectively investigated the mechanism of action of the two most potent compounds Vanillic acid (VA) and Epimedin C (Epi C). After identification of the anti-inflammatory and anabolic properties of VA and Epi C, the Ingenuity Pathway Analysis showed that in both treatment groups, osteoarthritic signaling pathways were inhibited. In the treatment group with VA, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling was inhibited by attenuation of the nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha (IκBα) phosphorylation. Epi C showed a significant anabolic effect by increasing the expression of collagenous and non-collagenous matrix proteins. In conclusion, VA, through inhibition of phosphorylation in NF-κB signaling pathway and Epi C, by increasing the expression of extracellular matrix components, showed significant anti-inflammatory and anabolic properties and might be potentially used in combination to treat or prevent joint OA.

Sustainable release of vancomycin from micro-arc oxidised 3D-printed porous Ti6Al4V for treating methicillin-resistant Staphylococcus aureus bone infection and enhancing osteogenesis in a rabbit tibia osteomyelitis model

Elimination of infection and enhancement of osteogenesis by orthopaedic implants are two critical factors in the treatment of complex bone infections. A prolonged and expensive procedure requiring two surgical steps and a 6-8-week period of joint immobilisation is utilised as a primary treatment for revision arthroplasty of an infected prosthesis, greatly affecting long-term patient care for the ageing population. Here, we evaluated the effects of vancomycin-loaded in micro-arc oxidised (MAO) three-dimensional (3D) printed porous Ti6Al4V scaffolds on osteogenesis. This system showed a high loading capacity and sustained vancomycin release kinetics, as demonstrated using high-performance liquid chromatography. In vivo, 0.1 mL of 10⁸ colony forming units (CFU) methicillin-resistant Staphylococcus aureus was injected into the tibias of rabbits to induce severe osteomyelitis. Physical, haematological, radiographic, microbiological, and histopathological analyses were performed to evaluate the effects of treatment. Rabbits with vancomycin-loaded in MAO scaffolds showed the inhibition of bone infection and enhancement of osteogenesis, resulting in better outcomes than in the other groups. Overall, these findings demonstrated the potential of this 3D printed porous Ti6Al4V, with good osteogenesis and sustained vancomycin release properties, for application in the treatment of complex bone infections.

The effects of morin on bone regeneration to accelerate healing in bone defects in mice

Restoring bone defects are the major challenge facing clinical trial therapy, particularly skull related problems. Morin, a naturally occurring compound, has pro-osteogenesis. This research focuses on assessing the role of morin for its pro-osteogenesis activities. We utilized in vivo and in vitro models to investigate the molecular-level mechanisms of morin's osteoblastic biological activity. The effectiveness of morin on pro-osteogenesis (100 mg/kg/day) was assessed by monitoring modifications in the bone histomorphometry score, the development of immature osteoblasts from mesenchymal stems cells and improvements in the expression of pro-osteogenic cytokines in skull defected (SD) mice. Quantitative-PCR, Western blot analysis, and immunofluorescence were studied to investigate the signaling pathways. Morin has a substantial in vivo pro-osteogenesis effect which can facilitate the development of osteoblasts, the production of osteoblast related marker genes, and in vitro protein markers for osteoblasts. From a molecular biology standpoint, morin contributes to the development of osteoblasts and stimulation of the Wnt pathway with the activation and translocation of β-catenin nuclei. Our findings from the study revealed that morin may be a beneficial substitute for helping regenerate bone defects.

Comparative In Vitro Evaluation of Antibacterial and Osteogenic Activity of Polysaccharide and Flavonoid Fractions Isolated from the leaves of Saussurea controversa

The osteogenic, cytotoxic, and antibacterial activities of polysaccharide (PS-SC) and flavonoid (F-SC) fractions isolated from the leaves extract of Saussurea controversa were studied in vitro. F-SC consists of the five quercetin glycosides in the ratio 2:8:10:1:4, which were isolated from the leaves extract of S. controversa and have been characterized previously. PS-SC was first isolated from the leaves extract of S. controversa and has been described. PS-SC consists in 30 compounds is characterized by a high degree of heterogeneity with a heterogeneity index of 19.74. The Mw and Mn of PS-SC were 108.6 and 5.5 kDa, respectively. Structural fragments are represented by galactose, arabinose, xylose, glucose, uronic acids, mannose, and rhamnose in a 10.1:3.3:2.2:2.1:1.7:0.9:0.5 molar ratio. F-SC as compared with PS-SC showed in vitro microbicidal (50 g/L) and better bacteriostatic (6.25 g/L versus 25 g/L of PS-SC) effects against the 24-h growth of Staphylococcus aureus strain 209 P and a 21-day absence of cytotoxicity on human adipose-derived multipotent mesenchymal stromal cells (hAMMSCs). Both fractions (PS-SC>F-SC) at doses of 10-50 mg/L stimulated differentiation of hAMMSCs into secreting osteoblasts accompanied by local mineralization of extracellular matrix. These fractions of S. controversa and especially F-SC, might be promising peroral drugs in the complex treatment of bone fractures and for prophylaxis of their infectious complications.

Chelidonic Acid and Its Derivatives from Saussurea Controversa: Isolation, Structural Elucidation and Influence on the Osteogenic Differentiation of Multipotent Mesenchymal Stromal Cells In Vitro

4-oxo-4H-pyran-2.6-dicarboxylic acid (chelidonic acid, ChA) in the native state and in the complex with calcium [Ca(ChA)(H₂O)₃], named saucalchelin (CaChA), was isolated from the extract of Saussurea controversa leaves for the first time for the Asteraceae family. The structure of ChA was determined by NMR, MS and confirmed by X-ray analysis of its monomethyl ester, and CaChA was described by IR, ICP-MS, CHN analysis. The yield of ChA and CaChA was 45 mg/g and 70 mg/g of extract, respectively. The osteogenic activity of ChA, n-monobutyl ester of chelidonic acid, and CaChA has been studied in vitro in a 21-day culture of human adipose-derived multipotent mesenchymal stromal cells (hAMMSCs) in a standard nutrient medium without osteogenic supplements. CaChA significantly stimulated the growth of cell mass and differentiation of hAMMSCs into osteoblasts with subsequent mineralization of the culture and it may be a promising substance for accelerating bone tissue regeneration and engineering.

Animal models of orthopaedic infections. A review of rabbit models used to induce long bone bacterial infections

The development of infections is one of the main complications in orthopaedics, especially in the presence of implants for the osteosynthesis of compound fractures and joint prosthesis. Indeed, foreign materials and implants act as substrates for the adhesion and proliferation of bacterial strains able to produce biofilm, causing peri-implant osteomyelitis. The eradication of biofilm remains a great challenge for the host immune system, as well as for medical and surgical approaches, thus imposing the need for new prophylactic and/or therapeutic strategies in which animal models have an essential role. In vivo orthopaedic models have mainly been used to study the pathogenesis of infections, biofilm behaviour and the efficacy of antimicrobial strategies, to select diagnostic techniques and test the efficacy of novel materials or surface modifications to impede both the establishment of bone infections and the associated septic loosening of implants. Among several models of osteomyelitis and implant-related infections described in small rodents and large animals, the rabbit has been widely used as a reliable and reproducible model of orthopaedic infections. This review examines the relevance of rabbits for the development of clinically representative models by analysing the pros and cons of the different approaches published in the literature. This analysis will aid in increasing our knowledge concerning orthopaedic infections by using this species. This review will be a tool for researchers who need to approach pre-clinical studies in the field of bone infection and have to identify the most appropriate animal model to verify their scientific hypothesis.

Preparation of micro-cell membrane chromatographic columns with polyvinyl alcohol-modified polyether ether ketone tube as cellular membrane carrier

Cell membrane chromatography is a promising technique for screening active components from complex matrices. Unfortunately, the large consumption of cells and low resolutions of analytes limit the applications of this method. Herein, we report polyether ether ketone tube as a novel cellular membrane carrier for cell membrane chromatography. Its inner surface is firstly coated by polyvinyl alcohol and then cell membranes are physically adsorbed onto the polyvinyl alcohol layer. To verify this approach, osteoclast and osteoblast micro-column were prepared and characterized by calcitonin and verapamil, respectively. Comparing with common cell membrane chromatographic column, the micro-cell membrane chromatographic columns showed about 1000-fold decrease of cell consumption and satisfactory retention behavior. The developed column was applied to screen potential active components from Cortex Phellodendri Chinensis. A total of 18 components in Cortex Phellodendri Chinensis extract were observed as having retention property of osteoclast micro-cell membrane chromatographic column, while 10 components retained on osteoblast micro-cell membrane chromatographic column. The results of in vitro assay showed that berberine, obacunoic acid and phellodendrine had an obvious inhibitory effect on osteoclast differentiation and function. Berberine and tetrahydropalmatine increased the osteoblast proliferations and mineralized nodules density. This cell membrane/polyvinyl alcohol column can be applied to various biological chromatography models.

Effects of alkaloids from Sophora flavescens on osteoblasts infected with Staphylococcus aureus and osteoclasts

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.

Icariin Enhances Bone Repair in Rabbits with Bone Infection during Post-infection Treatment and Prevents Inhibition of Osteoblasts by Vancomycin

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.

Efficient induction of antimicrobial activity with vancomycin nanoparticle-loaded poly(trimethylene carbonate) localized drug delivery system

Surgery and the local placement of an antibiotic are the predominant therapies to treat chronic osteomyelitis. Vancomycin-loaded N-trimethyl chitosan nanoparticles (VCM/TMC NPs) as a potential drug delivery system have high intracellular penetration and effective intracellular antibacterial activity. This study investigated the effects of a biocompatible material, poly(trimethylene carbonate) (PTMC), to increase the sustained effectiveness of an intracellular antibiotic and its potential application in antibiotic delivery. VCM/TMC NP-PTMC was characterized using scanning electron microscopy and Fourier transform infrared spectroscopy to determine the morphology, stability and chemical interaction of the drug with the polymer. Further, the biodegradation, antibacterial activity, protein adsorption, cell proliferation and drug release characteristics were evaluated. In addition, a Staphylococcus aureus-induced osteomyelitis rabbit model was used to investigate the antibiotic activity and bone repair capability of VCM/TMC NP-PTMC. The results showed that the composite beads of VCM/TMC NPs followed a sustained and slow release pattern and had excellent antibacterial activity and a higher protein adsorption and cell proliferation rate than the VCM-PTMC in vitro. Furthermore, VCM/TMC NP-PTMC inhibits bacteria and promotes bone repair in vivo. Thus, VCM/TMC NP-PTMC might be beneficial in periodontal management to reduce the bacterial load at the infection site and promote bone repair.