Cryptotanshinone protects against IL-1β-induced inflammation in human osteoarthritis chondrocytes and ameliorates the progression of osteoarthritis in mice

Progress in regulating inflammatory biomaterials for intervertebral disc regeneration

Intervertebral disc degeneration (IVDD) is rising worldwide and leading to significant health issues and financial strain for patients. Traditional treatments for IVDD can alleviate pain but do not reverse disease progression, and surgical removal of the damaged disc may be required for advanced disease. The inflammatory microenvironment is a key driver in the development of disc degeneration. Suitable anti-inflammatory substances are critical for controlling inflammation in IVDD. Several treatment options, including glucocorticoids, non-steroidal anti-inflammatory drugs, and biotherapy, are being studied for their potential to reduce inflammation. However, anti-inflammatories often have a short half-life when applied directly and are quickly excreted, thus limiting their therapeutic effects. Biomaterial-based platforms are being explored as anti-inflammation therapeutic strategies for IVDD treatment. This review introduces the pathophysiology of IVDD and discusses anti-inflammatory therapeutics and the components of these unique biomaterial platforms as comprehensive treatment systems. We discuss the strengths, shortcomings, and development prospects for various biomaterials platforms used to modulate the inflammatory microenvironment, thus providing guidance for future breakthroughs in IVDD treatment.

Revisiting prostaglandin E2: A promising therapeutic target for osteoarthritis

Osteoarthritis (OA) is a complex disease characterized by cartilage degeneration and persistent pain. Prostaglandin E2 (PGE2) plays a significant role in OA inflammation and pain. Recent studies have revealed the significant role of PGE2-mediated skeletal interoception in the progression of OA, providing new insights into the pathogenesis and treatment of OA. This aspect also deserves special attention in this review. Additionally, PGE2 is directly involved in pathologic processes including aberrant subchondral bone remodeling, cartilage degeneration, and synovial inflammation. Therefore, celecoxib, a commonly used drug to alleviate inflammatory pain through inhibiting PGE2, serves not only as an analgesic for OA but also as a potential disease-modifying drug. This review provides a comprehensive overview of the discovery history, synthesis and release pathways, and common physiological roles of PGE2. We discuss the roles of PGE2 and celecoxib in OA and pain from skeletal interoception and multiple perspectives. The purpose of this review is to highlight PGE2-mediated skeletal interoception and refresh our understanding of celecoxib in the pathogenesis and treatment of OA.

Natural products in osteoarthritis treatment: bridging basic research to clinical applications

Osteoarthritis (OA) is the most prevalent degenerative musculoskeletal disease, severely impacting the function of patients and potentially leading to disability, especially among the elderly population. Natural products (NPs), obtained from components or metabolites of plants, animals, microorganisms etc., have gained significant attention as important conservative treatments for various diseases. Recently, NPs have been well studied in preclinical and clinical researches, showing promising potential in the treatment of OA. In this review, we summed up the main signaling pathways affected by NPs in OA treatment, including NF-κB, MAPKs, PI3K/AKT, SIRT1, and other pathways, which are related to inflammation, anabolism and catabolism, and cell death. In addition, we described the therapeutic effects of NPs in different OA animal models and the current clinical studies in OA patients. At last, we discussed the potential research directions including in-depth analysis of the mechanisms and new application strategies of NPs for the OA treatment, so as to promote the basic research and clinical transformation in the future. We hope that this review may allow us to get a better understanding about the potential bioeffects and mechanisms of NPs in OA therapy, and ultimately improve the effectiveness of NPs-based clinical conservative treatment for OA patients.

Expanding the therapeutic potential of Salvia miltiorrhiza: a review of its pharmacological applications in musculoskeletal diseases

Salvia miltiorrhiz, commonly known as "Danshen" in Chinese medicine, has longstanding history of application in cardiovascular and cerebrovascular diseases. Renowned for its diverse therapeutic properties, including promoting blood circulation, removing blood stasis, calming the mind, tonifying the blood, and benefiting the "Qi", recent studies have revealed its significant positive effects on bone metabolism. This potential has garnered attention for its promising role in treating musculoskeletal disorders. Consequently, there is a high anticipation for a comprehensive review of the potential of Salvia miltiorrhiza in the treatment of various musculoskeletal diseases, effectively introducing an established traditional Chinese medicine into a burgeoning field.

AIM OF THE REVIEW

Musculoskeletal diseases (MSDs) present significant challenges to healthcare systems worldwide. Previous studies have demonstrated the high efficacy and prospects of Salvia miltiorrhiza and its active ingredients for treatment of MSDs. This review aims to illuminate the newfound applications of Salvia miltiorrhiza and its active ingredients in the treatment of various MSDs, effectively bridging the gap between an established medicine and an emerging field.

METHODS

In this review, previous studies related to Salvia miltiorrhiza and its active ingredients on the treatment of MSD were collected, the specific active ingredients of Salvia miltiorrhiza were summarized, the effects of Salvia miltiorrhiza and its active ingredients for the treatment of MSDs, as well as their potential molecular mechanisms were reviewed and discussed.

RESULTS

Based on previous publications, Salvianolic acid A, salvianolic acid B, tanshinone IIA are the representative active ingredients of Salvia miltiorrhiza. Their application has shown significant beneficial outcomes in osteoporosis, fractures, and arthritis. Salvia miltiorrhiza and its active ingredients protect against MSDs by regulating different signaling pathways, including ROS, Wnt, MAPK, and NF-κB signaling.

CONCLUSION

Salvia miltiorrhiza and its active ingredients demonstrate promising potential for bone diseases and have been explored across a wide variety of MSDs. Further exploration of Salvia miltiorrhiza's pharmacological applications in MSDs holds great promise for advancing therapeutic interventions and improving the lives of patients suffering from these diseases.

Network pharmacology identification and in vivo validation of key pharmacological pathways of Qin Jiao for gout and arthritis

Context: Gout is a chronic disease that imposes a huge financial and health burden on patients, which might diminish quality of life. Qin Jiao, a perennial herb found in northwestern China and Japan, is commonly used for treating various ailments.Objective: This study investigates the effects of Qin Jiao on gout and joint inflammation and elucidates its potential mechanism for gouty arthritis.Materials and methods: Study 1, a literature review was conducted using PubMed, Web of Science, and CNKI to assess the applications of Qin Jiao in arthritis treatment. Study 2 was performed to discover the component targets and gouty disease targets via TCMSP, OMIM, GeneCards and DRUGBANK, and network pharmacology analysis. Study 3, male Sprague-Dawley (SD) rats were divided into normal, model, colchicine, Qin Jiao low-dose (QJL), and Qin Jiao high-dose group (QJH), oral gavage for 40 d. Serum, synovial fluid, and synovial membrane tissue were collected to measure the expression levels of IL-1β, IL-6, and STAT3.Results: The research also identified potential targets and pharmacological pathways of Qin Jiao for gout treatment. In vivo study demonstrated Qin Jiao can reduce IL-1β levels in serum and ankle flushing fluid. ELISA analysis confirmed that Qin Jiao significantly reduces the protein expression of IL-6 and STAT3.Discussion and conclusion: Qin Jiao exerts anti-inflammatory effects on gouty arthritis by modulating the IL-6/STAT3 pathway. This study provides a biological basis for the use of Qin Jiao in treating arthritis-related diseases and offers experimental evidence for potential future drug development.

SARS-CoV-2 infection as a model to study the effect of cinnamaldehyde as adjuvant therapy for viral pneumonia

BACKGROUND

The recent pandemic outbursts, due to SARS-CoV-2, have highlighted once more the central role of the inflammatory process in the propagation of viral infection. The main consequence of COVID-19 is the induction of a diffuse pro-inflammatory state, also defined as a cytokine storm, which affects different organs, but mostly the lungs. We aimed to prove the efficacy of cinnamaldehyde, the active compound of cinnamon, as an anti-inflammatory compound, able to reduce SARS-CoV-2 induced cytokine storm.

RESULTS

We enrolled 53 COVID-19 patients hospitalized for respiratory failure. The cohort was composed by 39 males and 13 females, aged 65.0 ± 9.8 years. We reported that COVID-19 patients have significantly higher IL-1β and IL-6 plasma levels compared to non-COVID-19 pneumonia patients. In addition, human mononuclear cells (PBMCs) isolated from SARS-CoV-2 infected patients are significantly more prone to release pro-inflammatory cytokines upon stimuli. We demonstrated, using in vitro cell models, that macrophages are responsible for mediating the pro-inflammatory cytokine storm while lung cells support SARS-CoV-2 replication upon viral infection. In this context, cinnamaldehyde administration significantly reduces SARS-CoV-2-related inflammation by inhibiting NLRP3 mediated IL-1β release in both PBMCs and THP-1 macrophages, as well as viral replication in CaLu-3 epithelial cells. Lastly, aerosol-administered cinnamaldehyde was able to significantly reduce IL-1β release in an in vivo lung-inflammatory model.

CONCLUSION

The obtained results suggest the possible use of cinnamaldehyde as a co-adjuvant preventive treatment for COVID-19 disease together with vaccination, but also as a promising dietary supplement to reduce, more broadly, viral induced inflammation.

Tanshinone IIA and Cryptotanshinone Counteract Inflammation by Regulating Gene and miRNA Expression in Human SGBS Adipocytes

Inflammation of the adipose tissue contributes to the onset and progression of several chronic obesity-related diseases. The two most important lipophilic diterpenoid compounds found in the root of Salvia milthorrhiza Bunge (also called Danshen), tanshinone IIA (TIIA) and cryptotanshinone (CRY), have many favorable pharmacological effects. However, their roles in obesity-associated adipocyte inflammation and related sub-networks have not been fully elucidated. In the present study, we investigated the gene, miRNAs and protein expression profile of prototypical obesity-associated dysfunction markers in inflamed human adipocytes treated with TIIA and CRY. The results showed that TIIA and CRY prevented tumor necrosis factor (TNF)-α induced inflammatory response in adipocytes, by counter-regulating the pattern of secreted cytokines/chemokines associated with adipocyte inflammation (CCL2/MCP-1, CXCL10/IP-10, CCL5/RANTES, CXCL1/GRO-α, IL-6, IL-8, MIF and PAI-1/Serpin E1) via the modulation of gene expression (as demonstrated for CCL2/MCP-1, CXCL10/IP-10, CCL5/RANTES, CXCL1/GRO-α, and IL-8), as well as related miRNA expression (miR-126-3p, miR-223-3p, miR-124-3p, miR-155-5p, and miR-132-3p), and by attenuating monocyte recruitment. This is the first demonstration of a beneficial effect by TIIA and CRY on adipocyte dysfunction associated with obesity development and complications, offering a new outlook for the prevention and/or treatment of metabolic diseases.

Fermented jellyfish (Rhopilema esculentum) collagen enhances antioxidant activity and cartilage protection on surgically induced osteoarthritis in obese rats

Collagen has been considered a key treatment option in preventing damage to the articular cartilage over time and supporting the healing process, following the onset of osteoarthritis (OA). This study aimed to investigate the effect of collagen fermented from jellyfish (FJC) by Bacillus subtilis natto on anterior cruciate ligament transection with medial meniscectomy (ACLT + MMx)-induced knee OA in high-fat diet (HFD)-induced obesity in rats. The male Sprague-Dawley rats were fed an HFD for 6 weeks before ACLT + MMx surgery, after which they were administered a daily oral gavage of saline (control, OA, and OBOA), either with FJC (20 mg/kg, 40 mg/kg, and 100 mg/kg body weight) or glucosamine sulfate as a positive control (GS; 200 mg/kg body weight) for 6 weeks. Treatment with FJC decreased the fat weight, triglyceride, and total cholesterol levels in obese rats. Additionally, FJC downregulated the expression of some proinflammatory cytokines, including tumor necrosis factor-α, cyclooxygenase-2, and nitric oxide; suppressed leptin and adiponectin expression; and attenuated cartilage degradation. It also decreased the activities of matrix metalloproteinase (MMP)-1 and MMP-3. These results demonstrated that FJC showed a protective effect on articular cartilage and also suppressed the degradation of cartilage in an animal OA model, suggesting its potential efficacy as a promising candidate for OA treatment.

Radix Salvia miltiorrhiza for Ankylosing Spondylitis: Determining Potential Inflammatory Molecular Targets and Mechanism Using Network Pharmacology

Radix Salvia miltiorrhiza (RSM) is widely used for the clinical improvement of inflammatory diseases. However, the actions of RSM in the treatment of ankylosing spondylitis (AS) have not been fully explored. Therefore, this study was designed to use retrospective clinical data mining approach to understand the effects of RSM on AS-related immuno-inflammatory processes, use network pharmacology to predict therapeutic targets of RSM, and to further investigate the pharmacological molecular mechanism in vitro. RSM treatment has a long-term correlation with the improvement of AS-related immuno-inflammatory indicators through computational models. We established protein-protein interaction networks, conducted KEGG analysis to enrich significant TNF pathways, and finally obtained three core targets of RSM in the treatment of AS, namely, prostaglandin endoperoxide synthase 2 (PTGS2), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha). Screening of RSM active ingredients with node degree greater than 20 yielded cryptotanshinone and tanshinone IIA, and previous studies have reported their anti-inflammatory effects. In vitro, both cryptotanshinone and tanshinone IIA significantly inhibited the expressions of PTGS2, IL-6, and TNF-α in peripheral blood mononuclear cells in AS patients. In conclusion, cryptotanshinone and tanshinone IIA, which are the active components of RSM, may inhibit the activation of TNF signaling pathway in AS patients by downregulating the expression of PTGS2, IL-6, and TNF-α. These findings illustrate that RSM may be a promising therapeutic candidate for AS, but further validation is required.

Tamquam alter idem: formal similarities in a subset of reports on anti-inflammatory compounds in the years 2008–2019

A literature search on the in vitro testing of anti-inflammatory compounds of natural origin revealed a considerable number of studies adopting a similar template for data reporting in the years up to 2019. Sixty-five such reports appear to have been published between the years 2008 and 2019. Interestingly, this format template was clearly recognizable by a few hallmarks, such as a precise way of plotting cell viability data, extremely consistent endpoints, and the way these were graphically represented. In some instances the similarities extended to some textual features, such as in the case of figure legends. The similarity was so high that chance can be excluded and these studies can be safely assumed to have intentionally followed a template. By 2020, however, no new reports following this format have been published. Although a consistent and reproducible formatting for data reporting may improve report readability, this phenomenon should also be closely scrutinized to assess the rationale why it occurred, the validity of the endpoints that were chosen and why it was then abandoned. The present report reviewed the mean features of this format, traced its origin and its evolution over time, while discussing the limitations of this model.

Long noncoding RNA PVT1 promotes chondrocyte extracellular matrix degradation by acting as a sponge for miR-140 in IL-1β-stimulated chondrocytes

Background

Osteoarthritis (OA) is a common degenerative joint disease, and chondrocyte extracellular matrix (ECM) degradation is one vital pathological feature of OA. Long noncoding RNA (lncRNA), a new kind of gene regulator, plays an important role in pathogenesis of many diseases like OA. Recent studies have confirmed that lncRNA plasmacytoma variant translocation 1 (PVT1) expression was upregulated in OA patients; however, its effect on ECM degradation remained unknown.

Methods

Cartilage tissue samples were obtained from 6 OA patients admitted in Guangdong Second Traditional Chinese Medicine Hospital. Chondrocytes were isolated and cultured from the collected cartilage tissue. Plasmid construction, RNA interference, cell transfection, fluorescence in situ hybridization (FISH), and pull-down assay were carried out during the research.

Results

In this study, PVT1 expression was significantly increased in chondrocytes stimulated by interleukin-1β (IL-1β). In addition, inhibition of PVT1 significantly downregulated the increased expressions of ADAM metallopeptidase with thrombospondin type 1 motif-5 (ADAMTS-5) and matrix metalloproteinase-13 (MMP-13) induced by IL-1β. Further investigation revealed that PVT1 was an endogenous sponge RNA, which directly bound to miR-140 and inhibited miR-140 expression.

Conclusion

To sum up, this study showed that PVT1 promoted expressions of ADAMTS-5 and MMP-13 as a competing endogenous RNA (ceRNA) of miR-140 in OA, which eventually led to aggravation of ECM degradation, thus providing a new and promising strategy for the treatment of OA.

Cryptotanshinone Suppressed Postmenopausal Osteoporosis by Preventing RANKL-Mediated Osteoclastogenesis against Kidney Injury

Background

Cryptotanshinone (CPT), an active component extracted from the root of Salvia miltiorrhiza Bunge, exhibits extensive favorable bioactive properties including anti-inflammatory, antioxidative, antibacterial, and antitumor effects. This study aims to investigate the effects of CPT on osteogenesis and explore related mechanisms both in vivo and in vitro.

Methods

In the in vivo experiment, ovariectomized (OVX) female rats were intragastrically administered with CPT at doses of 10 mg/kg and 20 mg/kg for 13 consecutive weeks. Dual-energy X-ray absorptiometry was employed to detect bone mineral density (BMD). ELISA assay was leveraged to detect the biochemical parameters such as BUN and creatinine in the kidney samples. Bone and kidney sections were dyed by H&E and Masson staining kits. In the in vitro experiment, the RAW 264.7 cells were stimulated through the receptor activation of the nuclear factor kappa B ligand (RANKL) to establish an osteoclast differentiation model, and CPT's protective effect against bone loss was evaluated. Differentiated osteoclasts were determined by TRAP staining. While, osteoclast-marker proteins such as NFATc1, c-Fos, and cathepsin K were identified by Western blot.

Results

The results from in vivo experiments revealed that CPT could elevate bone mass and increase bone formation markers in OVX rats. Intriguingly, CPT administration noticeably ameliorated the kidney injury in OVX rats by suppressing BUN and restoring creatinine levels. Furthermore, the results from in vitro experiments suggested that CPT downregulated the protein expression of osteoclast-associated genes such as cathepsin K, c-Fos, and NFATc1 which hinted the related potential mechanisms.

Conclusion

The evidence from in vivo and in vitro experiments suggested that CPT exerted antiosteoclastogenic effects by inhibiting the activation of osteoclast differentiation followed by suppressing the protein expressions of cathepsin K, c-Fos, and NFATc1 in osteoclast precursors, and it exhibited protective effects against kidney damage, which highlighted its advantage in clinical application.

Vicenin 3 ameliorates ECM degradation by regulating the MAPK pathway in SW1353 chondrocytes

Aberrant destruction of the articular extracellular matrix (ECM) has been considered to be one of the pathological features of osteoarthritis (OA) which results in chondrocyte changes and articular cartilage degeneration. The MAPK signaling pathway serves a key role by releasing cartilage-degrading enzymes from OA chondrocytes. However, the use of MAPK inhibitors for OA is hindered by their potential long-term toxicity. Vicenin 3 is one of the major components of the Jian-Gu injection which is effective in the clinical treatment of OA. However, its potential impact on OA remain poorly understood. Therefore, the present study aimed to assess the effects of vicenin 3 on interleukin (IL)-1β-treated SW1353 chondrocytes, which mimic the microenvironment of OA. These chondrocytes were pretreated with vicenin 3 (0, 5 and 20 µM) for 1 h and subsequently stimulated with IL-1β (10 ng/ml) for 24 h. Nitric oxide (NO) production was measured using the Griess reaction, whereas the production of prostaglandin E2 (PGE2), matrix metalloproteinases (MMPs), A disintegrin-like and metalloproteinase with thrombospondin motifs (ADAMTSs), collagen type II and aggrecan were measured using ELISA. The mRNA expression of MMPs and ADAMTSs were measured using reverse transcription-quantitative PCR. The protein expression levels of MAPK were measured using western blotting. Vicenin 3 was found to significantly inhibit IL-1β-induced production of NO and PGE. Increments in the expression levels of MMP-1, MMP-3, MMP-13, ADAMTS-4 and ADAMTS-5 induced by IL-1β, in addition to the IL-1β-induced degradation of collagen type II and aggrecan, were all reversed by vicenin 3 treatment. Furthermore, vicenin 3 suppressed IL-1β-stimulated MAPK activation, an effect that was similar to that exerted by SB203580, a well-known p38 MAPK inhibitor. In conclusion, vicenin 3 may confer therapeutic potential similar to that of the p38 MAPK inhibitor for the treatment of OA.

Study on the Mechanism of Salvia miltiorrhiza in the Treatment of Traumatic Bone Defects

Traumatic bone defect is one of the major orthopedic diseases in clinics, and its incidence is increasing year by year. And repairing traumatic bone defects is a very difficult problem in clinics at present. The surface of medical titanium-based alloy has good biological properties, and its implant has a certain role in promoting bone in bone tissue. However, titanium-based materials are biologically inert and have no biological activity. As a traditional Chinese medicine, Salvia miltiorrhiza has the efficacy of treating bone diseases and promoting bone healing. The curative effect can be better exerted by loading the traditional Chinese medicine active compound Salvia miltiorrhiza on the surface of the titanium implant in a certain way. At present, due to the complex chemical composition of Salvia miltiorrhiza, the mechanism of its use for the treatment of traumatic bone defects is still unclear. Therefore, in this study, we mainly discussed the potential target and mechanism of Salvia miltiorrhiza in the treatment of traumatic bone defects through network pharmacology, which may provide a scientific basis for the treatment of traumatic bone defects with Salvia miltiorrhiza loaded on the surface of medical titanium-based alloy. We screened out effective compounds and targets of Salvia miltiorrhiza and targets related to traumatic bone defects with the help of relevant databases. The targets of Salvia miltiorrhiza for traumatic bone defects were analyzed by STRING and GeneCards databases, and the results were visualized by constructing a compound-target network, protein-protein interaction network, and compound-target-disease network with Cytoscape 3.7.1 analysis software. Finally, the selected core targets carried out GO and KEGG enrichment. The results showed that 60 main active components were screened from Salvia miltiorrhiza Bunge, which could act on 149 targets. There were 33 active components and 70 targets related to traumatic bone defects, respectively. The core targets of Salvia miltiorrhiza in the treatment of traumatic bone defects were MAPK1, MAPK10, MAPK14, TGFB1, and TNF. The results of enrichment analysis showed that Salvia miltiorrhiza might treat traumatic bone defects through an osteogenic differentiation pathway.

In Vitro Evaluation of the Anti-Inflammatory Effect of KMUP-1 and In Vivo Analysis of Its Therapeutic Potential in Osteoarthritis

Osteoarthritis is a degenerative arthropathy that is mainly characterized by dysregulation of inflammatory responses. KMUP-1, a derived chemical synthetic of xanthine, has been shown to have anti-inflammatory and antioxidant properties. Here, we aimed to investigate the in vitro anti-inflammatory and in vivo anti-osteoarthritis effects of KMUP-1. Protein and gene expressions of inflammation markers were determined by ELISA, Western blotting and microarray, respectively. RAW264.7 mouse macrophages were cultured and pretreated with KMUP-1 (1, 5, 10 μM). The productions of TNF-α, IL-6, MMP-2 and MMP- 9 were reduced by KMUP-1 pretreatment in LPS-induced inflammation of RAW264.7 cells. The expressions of iNOS, TNF-α, COX-2, MMP-2 and MMP-9 were also inhibited by KMUP-1 pretreatment. The gene expression levels of TNF and COX families were also downregulated. In addition, KMUP-1 suppressed the activations of ERK, JNK and p38 as well as phosphorylation of IκBα/NF-κB signaling pathways. Furthermore, SIRT1 inhibitor attenuated the inhibitory effect of KMUP-1 in LPS-induced NF-κB activation. In vivo study showed that KMUP-1 reduced mechanical hyperalgesia in monoiodoacetic acid (MIA)-induced rats OA. Additionally, KMUP-1 pretreatment reduced the serum levels of TNF-α and IL-6 in MIA-injected rats. Moreover, macroscopic and histological observation showed that KMUP-1 reduced articular cartilage erosion in rats. Our results demonstrated that KMUP-1 inhibited the inflammatory responses and restored SIRT1 in vitro, alleviated joint-related pain and cartilage destruction in vivo. Taken together, KMUP-1 has the potential to improve MIA-induced articular cartilage degradation by inhibiting the levels and expression of inflammatory mediators suggesting that KMUP-1 might be a potential therapeutic agent for OA.

Quantitative proteomics reveal the protective effects of EDS against osteoarthritis via attenuating inflammation and modulating immune response

ETHNOPHARMACOLOGICAL RELEVANCE

Epimedium brevicornu Maxim, Dioscorea nipponica Makino, and Salvia miltiorrhiza Bunge formula (EDS) are three traditional Chinese medicines commonly combined and used to treat osteoarthritis (OA). However, the mechanism of its therapeutic effect on OA is still unclear.

AIM OF THE STUDY

The aim of this study was to investigate the potential anti osteoarthritis mechanism of EDS in the treatment of OA rats' model by quantitative proteomics.

MATERIALS AND METHODS

A papain-induced rat OA model was established, and then EDS was intragastrically administered for 28 days. A label-free quantification proteomics was performed to evaluate the holistic efficacy of EDS against OA and identify the possible protein profiles mechanisms. The expression levels of critical changed proteins were validated by RT-qPCR and Western blotting. The effects of EDS were then assessed by evaluating pathologic changes in the affected knee joint and measuring pressure pain threshold, acoustic reflex threshold, angle of joint curvature.

RESULTS

Proteomics analysis showed that 62 proteins were significantly upregulated and 208 proteins were downregulated in OA group compared to control group. The changed proteins were involved in activation of humoral immunity response, complement cascade activation, leukocyte mediated immunity, acute inflammatory response, endocytosis regulation, and proteolysis regulation. The EDS treatment partially restored the protein profile changes. The protective effects of EDS on pathologic changes in OA rats' knee joint and pain threshold assessment were consisted with the proteomics results.

CONCLUSIONS

The results suggest that EDS exerted synergistic therapeutic efficacies to against OA through suppressing inflammation, modulating the immune system, relieving joint pain, and attenuating cartilage degradation.

Cryptotanshinone interferes with chondrocyte apoptosis in osteoarthritis by inhibiting the expression of miR‑574‑5p

Chondrocyte apoptosis is an important factor in the development and progression of osteoarthritis (OA). Cryptotanshinone (CTS) can inhibit chondrocyte apoptosis, but the specific mechanism remains unknown. The aim of the present study was to explore how CTS may affect chondrocyte apoptosis. Reverse transcription-quantitative PCR and western blotting were used to validate microRNA (miR)-574-5p, YY1-associated factor 2 (YAF2), Bcl-2 and Bax expression levels. H&E, Safranin O and TUNEL staining assays were used to evaluate the apoptosis of arthritic chondrocytes in vivo. A Cell Counting Kit-8 assay and flow cytometry were performed to detect cell proliferation and apoptosis of chondrocytes in vitro. The methylation level of the miR-574-5p promoter was measured via methylation specific PCR. The degree of chondrocyte apoptosis and the expression levels of YAF2 and Bcl-2 were decreased in the mice with OA, and were increased in the OA + CTS mice, while the expression levels of miR-574-5p and Bax showed opposite changes. Furthermore, the degree of chondrocyte apoptosis and the expression levels of the aforementioned key factors in chondrocytes were consistent with those observed in vivo. The methylation degree of the miR-574-5p promoter was increased by the addition of CTS, and was reduced after the addition of a methylation inhibitor, 5-aza-CdR, indicating that CTS could regulate the methylation of miR-574-5p promoter. The present study suggested that CTS could downregulate the expression of miR-574-5p by regulating its methylation, and thus, could improve YAF2 expression and affect chondrocyte apoptosis.

High expression of MAPK-14 promoting the death of chondrocytes is an important signal of osteoarthritis process

Background

Osteoarthritis (OA) is one of the most common degenerative diseases worldwide. Many researchers are studying the pathogenesis of OA, however, it is still unclear.

Methods

Screening and validation of OA relevant hub genes are an important part of exploring their potential molecular mechanism. Therefore, this study aims to explore and verify the mechanisms of hub genes in the OA by bioinformatics, qPCR, fluorescence and propidium iodide staining.

Results

Microarray datasets GSE43923, GSE55457 and GSE12021 were collected in the Gene Expression Omnibus (GEO), including 45 samples, which divided into 23 osteoarthritis knee joint samples and 22 samples of normal knee joint. Thereafter, 265 differentiallyexpressedgenes (DEGs) were identified in all, which divided into 199 upregulated genes and 66 downregulated genes. The hub genes MAPK-14, PTPRC, PTPN12 were upregulated, while B9D1 was downregulated. In order to further confirm the expression of screening differential genes in human chondrocytes, the human chondrocytes were extracted from a joint replacement surgery and stained with toluidine blue for identification. Compared with normal chondrocytes, OA chondrocytes had high expression of COL I protein and low expression of COL II protein. The expression levels of MAPK-14, PTPRC and PTPN12 in OA chondrocytes were significantly higher than the expression levels of B9D1 in normal chondrocytes. Moreover, the inflammatory necrosis of OA chondrocytes was increased compared with the normal chondrocytes by propidium iodide staining.

Conclusions

The high expression of MAPK-14 works as a promoter of chondrocytes death and an important signal of the osteoarthritis process.

A comparison of the efficacy and safety of traditional Chinese medicine external treatment for the knee osteoarthritis: A protocol for systematic review and network meta-analysis

BACKGROUND

Knee osteoarthritis (KOA), also known as degenerative osteoarthritis, is a common and frequently occurring disease in orthopedics with cartilage degeneration as the pathogenic cause and articular bone hyperplasia as the sign. Many studies have confirmed that KOA can be effectively treated by traditional Chinese medicine (TCM) external treatment. So we take advantage of the method of network meta-analysis to systematically compare the efficacy and safety of different types of TCM external treatment for the KOA.

METHODS

We will research on external treatment of KOA by traditional Chinese medicine using randomized controlled trials (RCTs) in search database (EMBASE, PubMed, Web of Science, Chinese National Knowledge Infrastructure [CNKI], Weipu database [VIP], Wanfang, and China BioMedical Literature [CBM]). The data and evidence obtained will be processed using Stata 15.0 and WinBUGS 1.4.3.

RESULTS

We will evaluate the efficacy and safety of traditional Chinese medicine external treatment for the knee osteoarthritis in this study.

CONCLUSION

This study will provide a new regimen for KOA treatment. It has extremely high reference value.

INPLASY REGISTRATION NUMBER

INPLASY2020120001.

DOI NUMBER

: 10.37766/inplasy2020.12.0001.

Mechanism of Salviae Miltiorrhizae Radix et Rhizoma in the Treatment of Knee Osteoarthritis Based on Network Pharmacology

Objective

The molecular mechanism of Salviae Miltiorrhizae Radix et Rhizoma (SMRR) in the treatment of knee osteoarthritis (KOA) was analyzed based on network pharmacology.

Methods

Active components and potential targets of SMRR were obtained from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform. KOA targets were obtained from the OMIM, DisGeNET, DrugBank, PharmGKB, and GeneCards Databases. The potential targets of SMRR in the treatment of KOA were identified by the Venn diagram. A protein-protein interaction network was generated with the STRING database. Visualization of the interactions in a potential pharmacodynamic component-target network was accomplished with Cytoscape software. The Database for Annotation, Visualization, and Integrated Discovery database and R software were used for Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway annotation analyses of common targets. Molecular docking of the potential leading components, as determined by efficacy with the core target molecules, was performed with Discovery Studio.

Results

Fifty-seven potential pharmacodynamic components and 58 potential targets of SMRR in the treatment of KOA were found. Bioinformatics analyses showed that the interleukin (IL)-17, hypoxia-inducible factor-1 (HIF-1), and tumor necrosis factor (TNF) signaling pathways, as well as the advanced glycation end product-receptor for advanced glycation end product signaling pathway in cases of diabetic complications, are related to the molecular mechanism of SMRR in the treatment of KOA. Molecular docking results showed that luteolin, tanshinone IIA, cryptotanshinone, and other components of SMRR had a strong affinity for MYC, signal transducer and activator of transcription 3, caspase-3 (CASP3), JUN, cyclin D1, prostaglandin endoperoxide synthase 2 (PTGS2), epidermal growth factor receptor (EGFR), mitogen-activated protein kinase 1 (MAPK1), protein kinase B, vascular endothelial growth factor A, and other targets.

Conclusion

SMRR indirectly regulates IL-17, HIF-1, TNF, and other signal transduction pathways by regulating the expression of proteins, including PTGS2, MAPK1, EGFR, and CASP3, thus playing a role in promoting chondrocyte proliferation, improving microcirculation, eliminating free radicals, and inhibiting inflammatory factors.

MMP-13 enzyme and pH responsive theranostic nanoplatform for osteoarthritis

Stimulus-responsive therapy permits precise control of therapeutic effect only at lesion of interest, which determines it a promising method for diagnosis and imaging-guided precision therapy. The acid environment and overexpressed matrix metalloproteinases-13 (MMP-13) are typical markers in osteoarthritis (OA), which enables the development of stimulus-responsive drug delivery system with high specificity for OA. We herein demonstrate a nano-micelle based stimuli-responsive theranostic strategy with reporting and drug release controlled by acidic pH and MMP-13 for OA therapy. Such nanoplatform is incorporated with a motif specifically targeting on cartilage, a motif responsive to matrix metalloproteinases-13 to specifically report OA condition and biodynamics of nano-micelles, an anti-inflammatory drug (e.g., psoralidin (PSO)) from traditional Chinese medicine, and a biocompatible polymeric skeleton for sustainable drug release in response to the acidic OA condition. The high effectiveness of this targeted precision therapy is demonstrated comprehensively by both in vitro and vivo evidences.

Cryptanshinone Inhibits the Glycolysis and Inhibits Cell Migration Through PKM2/β-Catenin Axis in Breast Cancer

Background

Breast cancer is one of the most prevalent gynecologic malignancies worldwide. Despite the high sensitivity in response to chemotherapy, drug resistance occurred frequently in clinical treatment. Cryptotanshinone (CTS) is a herbal medicine and has been identified as an anti-inflammatory and anti-oxidative drug.

Methods

In vitro assays, including the cell proliferation assay, colony formation assay, Western blot analysis, transwell migration/invasion assays, and cell scratch assay were used to explore the biological activities and working mechanism of CTS. Breast cancer cells were also transfected with PKM2 expressing vectors to define the molecular mechanisms involved in CTS-mediated anti-tumor activity.

Results

We found that CTS shows anti-proliferative effects and decreases the clonogenic ability of breast cancer cells. We also found that CTS inhibited the migration and invasion activity of MCF-7 and MDA-MB-231 cells by different analyzed methods. CTS also downregulated the levels of glycolysis-related proteins, such as PKM2, LDHA, and HK2. In addition, overexpression of PKM2 recovered CTS-mediated suppression of cell proliferation, colony formation, and cell mobility of breast cancer cells. We also found PKM2 was significantly overexpressed in tumor tissues and invasive ductal breast carcinoma compared to normal tissues and patients with high PKM2 expression had worse overall survival and metastasis-free survival outcomes.

Conclusion

CTS inhibited the proliferation, migration, and invasion of breast cancer cells. The involved mechanism may refer to the downregulation of the PKM2/β-catenin axis.

Recent advance in treatment of osteoarthritis by bioactive components from herbal medicine

Osteoarthritis (OA) is a common chronic articular degenerative disease, and characterized by articular cartilage degradation, synovial inflammation/immunity, and subchondral bone lesion, etc. The disease affects 2-6% of the population around the world, and its prevalence rises with age and exceeds 40% in people over 70. Recently, increasing interest has been devoted to the treatment or prevention of OA by herbal medicines. In this paper, the herbal compounds with anti-OA activities were reviewed, and the cheminformatics tools were used to predict their drug-likeness properties and pharmacokinetic parameters. A total of 43 herbal compounds were analyzed, which mainly target the damaged joints (e.g. cartilage, subchondral bone, and synovium, etc.) and circulatory system to improve the pathogenesis of OA. Through cheminformatics analysis, over half of these compounds have good drug-likeness properties, and the pharmacokinetic behavior of these components still needs to be further optimized, which is conducive to the enhancement in their drug-likeness properties. Most of the compounds can be an alternative and valuable source for anti-OA drug discovery, which may be worthy of further investigation and development.

Antagonism of GPR4 with NE 52-QQ57 and the Suppression of AGE-Induced Degradation of Type II Collagen in Human Chondrocytes

Osteoarthritis (OA) is a common degenerative joint disease for which an effective therapeutic strategy has not yet been established. AGEs are widely recognized as a contributor to OA pathogenesis. GPR4, a recently discovered proton-sensing transmembrane receptor, has been shown to possess a wide range of physiological functions. However, the potential role of this receptor in chondrocytes and the pathogenesis of OA is unclear. In the present study, we investigated the potential of GPR4 to modulate the effects of advanced glycation end products (AGEs) in SW1353 human chondrocytes. First, we demonstrate that GPR4 is fairly expressed in SW1353 chondrocytes and that exposure to AGEs increases the expression of this transmembrane receptor. Second, we found that antagonism of GPR4 with NE 52-QQ57 significantly inhibited the AGE-induced increased expression of several key inflammatory cytokines and signaling molecules, including tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, inducible nitric oxide synthase (iNOS), nitric oxide (NO), cyclooxygenase 2 (COX2), and prostaglandin E₂ (PGE₂). We also found that antagonisn of GPR4 had a remarkable ability to rescue type II collagen from AGE-induced degradation by inhibiting the expression of matrix metalloproteinase (MMP)-3 and MMP-13. As a key pro-inflammatory signaling pathway, we further tested the effect of GPR4 antagonism on the activation of nuclear factor-κB (NF-κB) and found that NF-κB activation was indeed suppressed, thereby indicating that the NF-κB signaling pathway may mediate the effects of GPR4 antagonism described above. These findings provide a basis for further research into the role of GPR4 -mediated signaling in OA.

Tougu Xiaotong capsules may inhibit p38 MAPK pathway-mediated inflammation: In vivo and in vitro verification

ETHNOPHARMACOLOGICAL RELEVANCE

Tougu Xiaotong capsules (TXC) are an herbal compound commonly used to treat osteoarthritis (OA) in China.

AIM OF THE STUDY

We attempted to verify TXC's therapeutic effects and mechanisms related to the p38 mitogen-activated protein kinase (MAPK) pathway in vivo and in vitro.

MATERIALS AND METHODS

TXC's therapeutic effects were assessed by observing cartilage degeneration and inflammatory factors in a modified Hulth's model (in vivo) and a lipopolysaccharides (LPS)-exposed cellular model (in vitro). The expression of biomarkers related to p38 MAPK pathway-mediated inflammation was also investigated.

RESULTS

TXC treatment reversed cartilage degeneration related biomarkers (ADAMTS 4, ADAMTS 5, Col I, Col V, MMP 3, MMP 9, and MMP 13) and inflammation factors (IL-1β, TNF-α, and IL-6) in both the animal and cellular OA models. Expression of p-p38 MAPK was downregulated following TXC administration, and changes to microRNAs in the cellular models were recovered. These results indicated that the p38 MAPK pathway-related mechanism may involve therapeutic effects of TXC.

CONCLUSIONS

This study verified TXC's efficacy to treat OA in vivo and in vitro and suggests that p38 MAPK pathway-related mechanisms may be involved in TXC's therapeutic effects.

Sinomenine Attenuates Cartilage Degeneration by Regulating miR-223-3p/NLRP3 Inflammasome Signaling

Sinomenine (SIN) has been shown to protect against IL-1β-induced chondrocyte apoptosis in vitro. However, the role of SIN in the anterior cruciate ligament transection (ACLT)-induced osteoarthritis (OA) mouse model and its underlying molecular mechanisms remain unclear. In the present study, the protective effect of SIN on ACLT-induced articular cartilage degeneration and IL-1β-induced chondrocyte apoptosis miR-223-3p/NLRP3 signaling regulation was investigated. Safranin O staining was performed to evaluate the pathological changes of articular cartilage. Chondrocyte apoptosis was measured with Annexin V-fluorescein isothiocyanate/polyimide (annexin V-FITC/PI) staining using flow cytometry. Gene and protein expression were detected by RT-qPCR and Western blotting, respectively. SIN administration markedly improved articular cartilage degradation in mice undergoing ACLT surgery. In addition, SIN treatment downregulated the levels of inflammatory cytokines and the protein expression of NLRP3 inflammasome components and upregulated the expression of miR-223-3p in OA mice and IL-1β-stimulated chondrocytes. In vitro, we found that NLRP3 was a direct target of miR-223-3p, and overexpression of miR-223-3p blocked IL-1β-induced apoptosis and the inflammatory response in chondrocytes. These findings indicate that miR-223-3p/NLRP3 signaling could be used as a potential target of SIN for the treatment of OA.

A network pharmacology approach to investigate the anti-inflammatory mechanism of effective ingredients from Salvia miltiorrhiza

Salvia miltiorrhiza, known as Danshen in Chinese, has been widely used to treat cardiovascular diseases in China. Tanshinone I (Tan I) and cryptotanshinone (CST) are the lipid-soluble and effective components from Salvia miltiorrhiza. However, the molecular mechanism of Tan I and CST for treating inflammation is still not known. Therefore, this study was designed to use network pharmacology-based strategy to predict therapeutic targets of Tan I and CST against inflammation, and further to investigate the pharmacological molecular mechanism in vitro. Inflammation targets were identified and followed by acquisition of verified targets of Tan I and CST. After constructing target-functional protein interaction network of Tan I and CST against inflammation, the core therapeutic targets of Tan I and CST against inflammation were obtained. Further, pathway enrichment analyses were performed on core therapeutic targets to evaluate key signaling pathways of Tan I and CST against inflammation. As revealed in network pharmacology analysis, 8 key hub targets for Tan I and CST against inflammation were identified, respectively: JUN, VEGFA, IL-6, TNF, MAPK8, CXCL8, and PTGS2 for Tan I, while STAT3, AKT1, CCND1, MAPK14, VEGFA, ESR1, MAPK8 and AR for CST. Pathway enrichment analysis by DAVID database indicated that Tan I and CST principally regulated the inflammation-associated pathway, such as TLR, JAK-STAT signaling pathway, focal adhesion, apoptosis, mTOR signaling pathway. In vitro, we found that both Tan I and CST exerts significantly effect on LPS stimulated NO secretion and iNOS expression in macrophages. Taken together, our data elucidate that anti-inflammatory pharmacological activities of Tan I and CST may be predominantly related to inhibition of TLR signaling pathway and regulating iNOS synthesis. These findings highlight the predicted therapeutic targets may be potential targets of Tan I and CST for anti-inflammation treatment.

Reversal of Epithelial-Mesenchymal Transition by Natural Anti-Inflammatory and Pro-Resolving Lipids

Epithelial mesenchymal transition (EMT) is a key process in the progression of malignant cancer. Therefore, blocking the EMT can be a critical fast track for the development of anticancer drugs. In this paper, we update recent research output of EMT and we explore suppression of EMT by natural anti-inflammatory compounds and pro-resolving lipids.

Cryptotanshinone attenuates allergic airway inflammation through negative regulation of NF-κB and p38 MAPK

This study is to determine the role and mechanism of cryptotanshinone (CTS) in allergic airway inflammation. Asthma induced by OVA was established in BALB/c mice. We found increased airway hyperresponsiveness (AHR), increased inflammatory cell infiltration, elevated levels of TNF-α, interleukin-1β (IL-1β), IL-4, IL-5, IL-6 and IL-13, decreased interferon gamma (IFN-γ) in lung tissue, increased content of total immunoglobulin E (IgE), OVA specific IgE, Eotaxin, ICAM-1, VCAM-1, nuclear factor-kappaB (NF-κB) and phosphorylation of p38 MAPK in lung tissue. However, the administration of CTS significantly decreased AHR in asthmatic mice, reduced inflammation around the bronchioles and inflammatory cells around airway, regulated cytokine production, reduced the total IgE and OVA-specific IgE levels, and inhibited NF-κB activation and p38 MAPK phosphorylation. In vitro experiments in 16 HBE cells revealed that CTS attenuated CAM-1 and IL-6 expression. These results indicate that CTS alleviates allergic airway inflammation by modulating p38 MAPK phosphorylation and NF-κB activation.

Cryptotanshinone Attenuates Inflammatory Response of Microglial Cells via the Nrf2/HO-1 Pathway

Cryptotanshinone (CTN), a monomer compound extracted from the dried roots and rhizomes of Salvia miltiorrhiza Bge, has a variety of pharmacological effects. However, little research has been done on the mechanism of CTN in attenuating neuroinflammation. The present study aimed to investigate whether CTN can ameliorate neuroinflammation induced by lipopolysaccharide (LPS) through the Nrf2/heme-oxygenase 1 (HO-1) signaling pathway in BV-2 microglial cells. We found that CTN attenuated the upregulated expression of inducible nitric oxide synthase, cyclooxygenase 2, NOD-like receptor pyrin domains-3, and nitric oxide induced by LPS in microglial cells. In addition, it curtailed the increased release of pro-inflammatory cytokines such as interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α in LPS-activated microglial cells. Furthermore, CTN significantly increased the levels of NF-κB, Nrf2, HO-1, and Akt proteins. We demonstrated that the anti-inflammatory action of CTN in BV-2 microglial cells was partially through the activation of the Nrf2/HO-1 pathway, which was regulated by the PI3K/Akt signaling pathway. Taken together, our results indicated that CTN downregulated the production and release of proinflammatory mediators in BV-2 microglial cells through activating the Nrf2/HO-1 pathway and subsequently protected neurons from inflammatory injury.

Protective Effects of Sweroside on IL-1β-Induced Inflammation in Rat Articular Chondrocytes Through Suppression of NF-κB and mTORC1 Signaling Pathway

Sweroside (SW), as a bioactive herbal ingredient, has anti-inflammatory effects. Protective effects of SW on IL-1β-stimulated articular chondrocytes, however, has not been fully understood. This study was to explore the anti-inflammatory effects and further to investigate the possible mechanism underlying SW effect on IL-1β-stimulated rat articular chondrocytes. Rat articular chondrocytes were cultured with or without SW for 1 h, and then stimulated with IL-1β for 24 h. ELISA analysis was used to measure the production of NO and PGE2. Western blot was to detect the expression of iNOS and COX-2. Furthermore, the mRNA expression of MMP-1, MMP3, MMP13, and ADAMTS-5 were measured by q-PCR. These results demonstrated that SW significantly inhibited IL-1β-induced NO and PGE2 production, as well as MMP-1, MMP3, MMP13, and ADAMTS-5 mRNA expression. Moreover, SW also suppressed IL-1β-induced NF-κB activation and iκ-B degradation, S6K1 and S6 phosphorylation. In conclusion, these results strongly demonstrated that the anti-inflammatory activity of SW is in part mediated by suppressing NF-κB and mTORC1 signaling, which was expected to be a promising drug target of osteoarthritis therapy.

Artesunate alleviates interleukin‑1β‑induced inflammatory response and apoptosis by inhibiting the NF‑κB signaling pathway in chondrocyte‑like ATDC5 cells, and delays the progression of osteoarthritis in a mouse model

Osteoarthritis (OA) is a progressive and degenerative joint disorder that is highly prevalent worldwide and for which there is currently no effective medical therapy. Artesunate (ART), a natural compound used to treat malaria, possesses diverse biological properties, including the regulation of inflammation and apoptosis in various cells; however, its role in OA remains unclear. The aim of the present study was to investigate the effects of ART on interleukin (IL)‑1β‑induced chondrocyte‑like ATDC5 cells and in an OA mouse model. The results revealed that ART dose‑dependently relieved the inhibitory effect of IL‑1β on cell viability. Moreover, ART significantly reduced the overexpression of matrix metalloproteinase (MMP)‑3, MMP‑13, a disintegrin and metalloproteinase with thrombospondin motifs‑5 and cyclooxygenase‑2 at both the gene and protein levels in chondrocyte‑like ATDC5 cells stimulated by IL‑1β. Furthermore, ART decreased the expression of pro‑apoptotic Bax, cleaved caspase‑3 and cleaved caspase‑7 in a dose‑dependent manner, and increased the expression of the anti‑apoptotic factor Bcl‑2. These changes were mediated by the inhibitory effect of ART on the nuclear factor‑κB signaling pathway, defined as repression of the phosphorylation of IκBα and p65, and improved redistribution of p65. Additionally, ART blocked the advancement of the calcified cartilage zone and the loss of proteoglycan, and lowered histological scoring of OA in a mouse model. Taken together, these results indicate that ART may be of value as a therapeutic agent for OA.

Astragaloside inhibits IL-1β-induced inflammatory response in human osteoarthritis chondrocytes and ameliorates the progression of osteoarthritis in mice

Background: Osteoarthritis (OA) is a chronic joint-degeneration disease and accounts for the most frequent arthritis in aging people. OA is characterized by the degeneration of articular cartilage, subchondral bone sclerosis and synovitis. Inflammation as an important role in OA progression, in that anti-inflammatory agents could effectively inhibit the development of OA with minimal side effects, therefore developing a nature anti-inflammatory compound will be a promising therapy for treating OA. Methods: We treated patient-derived chondrocytes and mouse models of OA with astragaloside, an effective component of astragalus membranaceus, and measured its effect on pro-inflammatory cytokines and OA progression in mice. Results: In vitro, astragaloside induced a dose-dependent inhibition of IL-1β-induced the production of inflammatory factors, including interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), nitric oxide (NO), prostaglandin E2 (PGE2), expression of MMP 13 and ADAMTS-5, and the activation of NF-κB signaling. In vivo, astragaloside ameliorate the degeneration of cartilage in mouse model of OA. Conclusion: Astragaloside potentially serve as a promising and effective therapeutic agent for treating OA patients.

Cryptotanshinone inhibits RANKL-induced osteoclastogenesis by regulating ERK and NF-κB signaling pathways

Osteoporosis (OS) is one of the most common healthy problems characterized by low bone mass. Osteoclast, the primary bone-resorbing cell, is responsible for destructive bone diseases including osteoporosis (OS). Cryptotanshinone (CTS), an active component extracted from the root of Salvia miltiorrhiza bunge, has been shown to prevent the destruction of cartilage and the thickening of subchondral bone in mice osteoarthritis models. However, its molecular mechanism in osteoclastogenesis needs to be determined. The aim of the current study was to explore the effect of CTS on osteoclastogenesis and further evaluate the underlying mechanism. Our results showed that CTS inhibited receptor activator of NF-κB ligand (RANKL)-induced the increase in tartrate-resistant acid phosphatase (TRAP) activity in bone marrow-derived macrophages (BMMs). In addition, the expressions of osteoclastogenesis-related marker proteins and nuclear factor of activated T-cells (NFAT) activation were suppressed by CTS treatment in BMMs. Furthermore, CTS attenuated RANKL-induced ERK phosphorylation and NF-κB activation in BMMs. These findings indicated that CTS inhibited RANKL-induced osteoclastogenesis by inhibiting ERK phosphorylation and NF-κB activation in BMMs. Thus, CTS may function as an inhibitor of osteoclastogenesis and may be considered as an alternative medicine for the prevention and treatment of OS.

Cryptotanshinone Attenuates Oxidative Stress and Inflammation through the Regulation of Nrf-2 and NF-κB in Mice with Unilateral Ureteral Obstruction

Oxidative stress and inflammatory responses are closely implicated in the progression of renal interstitial fibrosis, thereby leading to chronic kidney disease. Cryptotanshinone (CTS) is a natural compound involved in antioxidant and anti-inflammatory activities. We evaluated the effects of CTS on inflammation and oxidative stress in obstructed kidneys. Mice received gastric gavage of CTS from 7 days before unilateral ureteral obstruction operation to 1 week after surgery. Administration of CTS at 50 and 100 mg/kg/day significantly decreased collagen production, as shown by Masson staining. Immunohistochemistry staining and RT-PCR confirmed that CTS reduced extracellular matrix proteins, such as fibronectin and collagen-1, in the obstructed kidneys in a dose-dependent manner. Furthermore, immunohistochemistry staining indicated that CTS inhibited infiltration of the macrophage (CD68-positive) and lymphocyte (CD3-positive) cells, which were associated with the suppression of the nuclear factor-κB signalling activation. CTS increased superoxide dismutase, catalase and glutathione while decreased malondialdehyde production. More importantly, CTS activated Nrf-2 and HO-1 in the obstructed kidneys for 7 days. CTS could protect renal interstitial fibrosis by ameliorating inflammation and oxidative stress, which might be through the regulation of NF-κB and Nrf-2/HO-1 signalling pathways.

Anti-Inflammatory Effect of Geniposide on Osteoarthritis by Suppressing the Activation of p38 MAPK Signaling Pathway

It has been suggested that the activation of the p38 mitogen activated protein kinases (MAPKs) signaling pathway plays a significant role in the progression of OA by leading to the overexpression of proinflammatory cytokines, chemokines, and signaling enzymes in human osteoarthritis chondrocytes. However, most p38 MAPK inhibitors applied for OA have been thought to be limited due to their potential long-term toxicities. Geniposide (GE), an iridoid glycoside purified from the fruit of the herb, has been widely used in traditional medicine for the treatment of a variety of chronic inflammatory diseases. In this study, we evaluated the inhibition effect of geniposide on the inflammatory progression of the surgically induced osteoarthritis and whether the protective effect of geniposide on OA is related to the inhibition of the p38 MAPK signaling pathway. In vitro, geniposide attenuated the expression of inflammatory cytokines including interleukin-1 (IL-1), tumor necrosis factor (TNF-α), and nitric oxide (NO) production as well as matrix metalloproteinase- (MMP-) 13 in chondrocytes isolated from surgically induced rabbit osteoarthritis model. Additionally, geniposide markedly suppressed the expression of IL-1, TNF-α, NO, and MMP-13 in the synovial fluid from the rabbits with osteoarthritis. More importantly, our results clearly demonstrated that the inhibitory effect of geniposide on surgery-induced expression of inflammatory mediators in osteoarthritis was closely associated with the suppression of the p38 MAPK signaling pathways. Our study demonstrates that geniposide may have therapeutic potential to serve as an alternative agent for the p38 MAPK inhibition for the treatment of OA due to its inherent features of biological activities and low toxicity as a traditional Chinese medicine.

Cryptotanshinone Protects Cartilage against Developing Osteoarthritis through the miR-106a-5p/GLIS3 Axis

Cryptotanshinone (CTS) has emerged as an anti-inflammatory agent in osteoarthritis (OA). However, the molecular mechanism underlying its potent therapeutic effect on OA remains largely unknown. MicroRNAs (miRNAs) act as crucial regulators in maintaining cartilage homeostasis. To investigate whether CTS protects against developing OA through regulation of miRNAs, we examined the potential CTS-mediated miRNA molecules using microarray analysis. We found that CTS significantly promoted miR-106a-5p expression in chondrocytes. Using the OA mouse model created by anterior cruciate ligament transection, we revealed that intra-articular injection of miR-106a-5p agomir attenuated OA. In addition, miR-106a-5p inhibited GLI-similar 3 (GLIS3) production by directly targeting the 3′ untranslated region. CTS promoted miR-106a-5p expression through recruitment of a member of the paired box (PAX) family of transcription factors, PAX5, to the miR-106a-5p promoter. Inhibition of PAX5 mimicked the effect of miR-106a-5p and abolished the CTS ability to regulate miR-106a-5p expression. In OA patients, miR-106-5p is downregulated which is accompanied by downregulation of PAX5 and upregulation of GLIS3. Collectively, these data highlight that the PAX5/miR-106a-5p/GLIS3 axis acts as a novel pleiotropic regulator in CTS-mediated OA cartilage protection, suggesting that miR-106a-5p and PAX5 activation and GLIS3 inhibition might be useful and attractive for therapeutic strategies to treat OA patients.

miRNA‑27a regulates arthritis via PPARγ in vivo and in vitro

The present study investigated the role of microRNA (miR)‑27a in the development of arthritis and its mechanism of action. Initially, collagen was used to develop an in vivo rat model of arthritis. Changes in the miRs in the rats were analyzed. It was subsequently observed that miR‑27a expression was reduced in patients with arthritis, compared with the control group. In the present study an in vitro miR‑27a overexpression model of arthritis was established and it was observed that miR‑27a increased the proliferation of osteoblast‑like cells in vitro. miR‑27a overexpression promoted osteogenic differentiation, increased alkaline phosphatase (ALP) and osteoporosis (OST) content, induced insulin‑like growth factor binding protein-5 (IGFBP‑5) protein expression, reduced inflammation and suppressed peroxisome proliferator‑activated receptor γ (PPARγ) and matrix metalloproteinase-17 (MMP‑17) protein expression in arthritis. However, miR‑27a downregulation inhibited osteogenic differentiation, increased inflammation and PPARγ and MMP‑17 protein expression and suppressed ALP and OST content in an in vitro model of arthritis. The PPARγ inhibitor reduced the function of miR‑27a downregulation on arthritis. Therefore the results of the present study revealed that miR‑27a regulates arthritis via PPARγ.

Histone deacetylase-4 and histone deacetylase-8 regulate interleukin-1β-induced cartilage catabolic degradation through MAPK/JNK and ERK pathways

Interleukin-1β (IL-1β)-induced inflammatory response is associated with osteoarthritis (OA) and its development. Histone deacetylase (HDAC) may be involved in regulating this pathogenesis, but the mechanism has yet to be elucidated. The aim of the present study was to investigate the mechanism underlying the regulation of IL-1β-stimulated catabolic degradation of cartilage by HDAC. An in vitro model of OA was generated using rat articular chondrocytes (rACs) treated with IL-1β. The role of HDAC in IL-1β-induced gene expression was investigated using HDAC inhibitors and specific small interfering RNAs (siRNAs). The association of diverse mitogen-activated protein kinase (MAPK) pathways was examined. The IL-1β-induced expression of a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-4 and ADAMTS-5, and the production of collagen X and cyclo-oxygenase-2 in rACs was accompanied by the expression of HDAC4 and HDAC8, and were significantly downregulated by HDAC inhibitors and specific siRNAs. IL-1β-induced activation of extracellular signal-regulated kinase was downregulated by the HDAC inhibitor Trichostatin A, but not significantly by PCI-34051. The activation of c-Jun N-terminal kinase was observably downregulated by the latter, but only slightly by the former. These results suggest that HDAC4 and HDAC8 may serve as key upstream mediators of MAPK in regulating the IL-1β-induced cartilage catabolic and degradation. Therefore, inhibiting HDAC4 or HDAC8 or both may be a promising therapeutic strategy in preventing and treating OA.

Downregulating PI3K/Akt/NF-κB signaling with allicin for ameliorating the progression of osteoarthritis:in vitroandvivostudies

A schematic illustration of the potential protective effects of allicin on osteoarthritis development.