Danshensu inhibits the IL-1β-induced inflammatory response in chondrocytes and osteoarthritis possibly via suppressing NF-κB signaling pathway

LncRNA NKILA attenuates the progression of osteoarthritis through the targeted inhibition of the NF-κB pathway

BACKGROUND

Interleukin-1β (IL-1β) plays a crucial role in cartilage degeneration by inducing inflammatory cascades in chondrocytes, impairing their normal biological functions. Long non-coding RNA NKILA (lncRNA NKILA) has been implicated in osteoarthritis (OA), but its specific molecular mechanisms remain unclear. This study aims to elucidate the function and molecular regulatory mechanism of lncRNA NKILA in articular chondrocytes under IL-1β stimulation.

METHODS

Primary human articular chondrocytes were cultured to investigate the effects of IL-1β on chondrocyte proliferation, apoptosis, and extracellular matrix metabolism. We employed Reverse Transcription Quantitative Polymerase Chain Reaction (RT-qPCR), western blot, flow cytometry, immunofluorescence, and nuclear mass separation assays to explore the interaction between lncRNA NKILA and the NFκB signaling pathway. Additionally, animal experiments were conducted to evaluate the therapeutic potential of modulating lncRNA NKILA expression in vivo.

RESULTS

IL-1β treatment led to decreased chondrocyte proliferation and increased apoptosis. Our study demonstrated that IL-1β downregulates lncRNA NKILA, which weakens its inhibitory effect on the NFκB (Nuclear Factor Kappa B) signaling pathway. This downregulation results in increased NFκB activity and exacerbates chondrocyte degeneration. Notably, the upregulation of lncRNA NKILA significantly alleviated OA symptoms, indicating that NKILA could be a promising therapeutic target.

CONCLUSION

IL-1β reduces lncRNA NKILA expression, weakening its inhibition of NFκB signaling and promoting articular chondrocyte degeneration. Enhancing lncRNA NKILA expression offers a promising approach to mitigating OA, suggesting that NKILA could serve as a potential therapeutic target for OA treatment.

Rosmarinic acid promotes cartilage regeneration through Sox9 induction via NF-κB pathway inhibition in mouse osteoarthritis progression

Background

The natural polyphenolic compound known as Rosmarinic acid (RosA) can be found in various plants. Although its potential health benefits have been extensively studied, its effect on osteoarthritis (OA) progression and cartilage regeneration function still needs to be fully elucidated in OA animal models. This study elucidated the effect of RosA on OA progression and cartilage regeneration.

Methods

In vitro assessments were conducted using RT-PCR, qRT-PCR, Western blotting, and ELISA to measure the effects of RosA. The molecular mechanisms of RosA were determined by analyzing the translocation of p65 into the nucleus using immunocytochemistry (ICC). Histological analysis of cartilage explant was performed using alcian blue staining and immunohistochemistry (IHC). For in vivo analysis, the destabilization of the medial meniscus (DMM)-induced OA mouse model was utilized to evaluate cartilage destruction through Safranin-O staining. The expression of catabolic and anabolic factors in mice knee joints was quantified by immunohistochemistry.

Results

The expression of catabolic factors in chondrocytes was significantly impeded by RosA. It also suppressed the NF-κB signaling pathway by decreasing phosphorylation of p65 and reducing degradation of IκB protein. In ex vivo experiments, RosA protected sulfated proteoglycan erosion triggered by IL-1β and suppressed the catabolic factors in cartilage explant. RosA treatment in animal models resulted in preventing cartilage destruction and reducing catabolic factors in the cartilage. RosA was also found to promote the expression of Sox9, Col2a1, and Acan in vitro, ex vivo, and in vivo analyses.

Conclusions

RosA attenuated the OA progression by suppressing the catabolic factors expression. These effects were facilitated through the suppression of the NF-κB signaling pathway. Additionally, it promotes cartilage regeneration by inducing anabolic factors. Therefore, RosA shows potential as an effective therapeutic agent for treating OA.

Effects of herbal wet compresses on pain intensity, inflammatory factor levels, and quality of life in patients with pain

OBJECTIVE

To investigate the pharmacological mechanisms and clinical effects of Traditional Chinese Medicine (TCM) wet compresses on pain, inflammation, and quality of life in patients with soft tissue injuries.

METHODS

First, the network pharmacology of the active ingredients from TCM wet compresses were identified using the TCMSP (Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform) database (Common monkshood mother root, Two-toothed achyranthes root, Sour orange, Garden balsam stem, Safflower, Ground beetle, Zingiber, Haichow elsholtzia herb). Relevant targets for soft tissue injuries were obtained from GeneCards, revealing 20 key therapeutic targets. Pathway clustering highlighted inflammation-related pathways. Then we conducted clinical investigation by retrospectively analyzing the data of 80 patients with soft tissue injury treated in our hospital from January 2023 to December 2023. The data from healthy subjects who had physical examination in our hospital during the same period served as the control group (n=40). According to the treatment plan, the patients were divided into study group A (n=40, external treatment with Voltaalin ointment), and study group B (n=40, treatment with TCM wet compress). Pain intensity, inflammatory factor levels, and quality of life of the patients between the two groups were compared.

RESULTS

Analysis of TCM wet compresses revealed 86 active ingredients and 259 intersecting targets, with key ingredients including sitogluside, beta-sitosterol, and quercetin. Key targets included IL-6, IL-1B, TNF, CXCL8, and IL10. Clinically, both patient groups showed significant reductions in pain and inflammatory markers, with greater improvements in study group B. In addition, quality of life improved notably post-treatment in study group B.

CONCLUSION

TCM wet compress patches are effective in reducing pain, modulating inflammation, and improving the quality of life in patients with soft tissue injury. These findings support TCM wet compresses as a promising alternative treatment.

SNORC knockdown alleviates inflammation, autophagy defect and matrix degradation of chondrocytes in osteoarthritis development

Excessive inflammation and autophagy defect of chondrocytes play important roles in the pathological process of osteoarthritis (OA). The present study aimed to clarify the roles of small novel rich in cartilage (SNORC) in these pathological changes of chondrocytes in OA. Bioinformatics analysis of GEO dataset GSE207881 displayed that SNORC was a potential biomarker for OA. As confirmed by quantitative real-time PCR, immunohistochemical staining and western blotting, SNORC was significantly up-regulated in cartilage of OA rat model and interleukin (IL)-1β-stimulated primary rat articular chondrocytes in contrast to their corresponding normal control. Knocking down SNORC in IL-1β-induced chondrocytes obviously suppressed the production of nitric oxide (NO), IL-6, tumor necrosis factor (TNF)-α and prostaglandin E2 (PGE2) to alleviate inflammation, and reduced the protein levels of a disintegrin and metalloproteinase with thrombospondin 5 (ADAMTS5) and matrix metallopeptidase (MMP)13 and elevated collagen type 2 alpha 1 (COL2A1) level to improve matrix degradation. Down-regulation of SNORC increased Beclin1 expression and LC3II/LC3I ratio, but suppressed p62 expression to restore impaired autophagy in IL-1β-induced chondrocytes. Moreover, down-regulating SNORC mitigated mitochondrial dysfunction and apoptosis in IL-1β-stimulated chondrocytes. Mechanically, SNORC simultaneously activated the phosphatidylinositol-3-kinase/serine threonine kinase (PI3K/AKT) and c-Jun N-terminal kinase (JNK)/c-Jun signaling pathway in the IL-1β-induced chondrocyte, while re-activating the PI3K and JNK signals abolished the suppressive effect of down-regulating SNORC on IL-1β-induced chondrocyte damage. In a word, SNORC knockdown alleviates inflammation, matrix degradation, autophagy defect and excessive apoptosis of chondrocytes during OA development via suppressing the PI3K and JNK signaling pathway.

HPLC combined with chemometrics for quality control of Huamoyan Granules or Capsules

Objective

Huamaoyan Granules (HMYG) and Huamaoyan Capsules (HMYC) are Chinese patent medicines with different dosage forms of the same prescription. Due to the different preparation process, the chemical composition of these Chinese patent medicines varies greatly among different forms, but there were few studies on the difference comparison and quality control of them. In order to improve the effectiveness and safety in its clinical application, an idea combining high performance liquid chromatography (HPLC) and chemometrics was put forward to study the quality control of Chinese patent medicines in different dosage forms of the same prescription.

Methods

The differential markers of HMYG and HMYC were explored based on HPLC fingerprint and chemometrics including orthogonal projections to latent structures-discriminant analysis (OPLS-DA), principal component analysis (PCA), and hierarchical cluster analysis (HCA). Finally, the quantitative analysis method of related components was established by HPLC.

Results

A quality control method for HMYG and HMYC was established. Firstly, the chemical components of HMYG and HMYC were systematically analyzed by HPLC fingerprinting. Further exploration showed that there were 20 characteristic peaks and 57 common peaks. Then, the potential differential markers between HMYG and HMYC were explored by chemometrics, and the differential markers were screened after intersection with the 20 characteristic peaks. Finally, HPLC quantitative analysis methods for nine components were established, including seven differential markers (neochlorogenic acid, protocatechualdehyde, chlorogenic acid, cryptochlorogenic acid, caffeic acid, rosmarinic acid and salvianolic acid A). The results of HPLC quantitative analysis showed that the contents of eight components in HMYG and HMYC samples were significantly different. According to the above results, the differential markers between HMYG and HMYC screened based on HPLC fingerprint and chemometrics can effectively characterize the differences between the two dosage forms.

Conclusion

The present work provides a rapid and effective method for routine quality evaluation and control of HMYG and HMYC. This work also provides feasible methods for the quality evaluation and control of Chinese patent medicines with different dosage forms of the same prescription.

Yishen Tongbi decoction attenuates inflammation and bone destruction in rheumatoid arthritis by regulating JAK/STAT3/SOCS3 pathway

Background

Yishen-Tongbi Decoction (YSTB), a traditional Chinese prescription, has been used to improve syndromes of rheumatoid arthritis (RA) for many years. Previous research has shown that YSTB has anti-inflammatory and analgesic properties. However, the underlying molecular mechanism of the anti-RA effects of YSTB remains unclear.

Purpose and study design

The purpose of this research was to investigate how YSTB affected mice with collagen-induced arthritis (CIA) and RAW264.7 cells induced with lipopolysaccharide (LPS).

Results

The findings show that YSTB could significantly improve the clinical arthritic symptoms of CIA mice (mitigate paw swelling, arthritis score, thymus and spleen indices, augment body weight), downregulated expression of pro-inflammatory cytokines like tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), IL-6 and IL-17, while upregulated the level of anti-inflammatory like IL-10 and transforming growth factor-β (TGF-β). Meanwhile, YSTB inhibits bone erosion and reduces inflammatory cell infiltration, synovial proliferation, and joint destruction in CIA mice. In addition, we found that YSTB was able to suppress the LPS-induced inflammation of RAW264.7 cells, which was ascribed to the suppression of nitric oxide (NO) production and reactive oxygen species formation (ROS). YSTB also inhibited the production of inducible nitric oxide synthase and reduced the releases of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 in LPS-induced RAW264.7 cells. Furthermore, the phosphorylation expression of JAK2, JAK3, STAT3, p38, ERK and p65 protein could be suppressed by YSTB, while the expression of SOCS3 could be activated.

Conclusion

Taken together, YSTB possesses anti-inflammatory and prevention bone destruction effects in RA disease by regulating the JAK/STAT3/SOCS3 signaling pathway.

LncRNA SNHG1 overexpression alleviates osteoarthritis via activating PI3K/Akt signal pathway and suppressing autophagy

We hereby intend to further explore and confirm the underlying mechanism of Small nucleolar RNA Host Gene 1 (SNHG1) in osteoarthritis (OA). For in vitro assays, OA was induced in primary chondrocytes with interleukin-1β (IL-1β) treatment; while for in vivo tests, OA model was established in mice using the destabilization of the medial meniscus (DMM) method. Cell viability and apoptosis were assessed with MTT and flow cytometry assays, respectively. Cartilage tissue was stained by Safranin-O/Fast Green Staining. The mRNA and protein levels were separately determined via quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. SNHG1 overexpression promoted the viability yet inhibited the apoptosis of chondrocytes injured by IL-1β. Moreover, the overexpression of SNHG1 promoted B-cell lymphoma-2 (Bcl-2) expression and activated phosphoinositol-3 kinase (PI3K)/protein kinase B (Akt) pathway but suppressed the process of autophagy, which led to down-regulation of light chain 3 (LC3)-II/I level and up-regulation of P62 level. However, rapamycin (RAPA, an autophagy activator) and LY294002 (a PI3K inhibitor) reversed the effects of SNHG1 overexpression on the viability and apoptosis of chondrocytes as well as on the proteins related to PI3K/Akt pathway and autophagy. In OA-modeled mice, SNHG1 overexpression prevented the loss of chondrocytes via the activation of PI3K/Akt pathway and the suppression of autophagy. SNHG1 overexpression might inhibit the apoptosis of chondrocytes by promoting PI3K/Akt pathway and inhibiting autophagy.

The antagonism mechanism of astilbin against cadmium-induced injury in chicken lungs via Treg/Th1 balance signaling pathway

The purpose of this study was to investigate the effect of Treg/Th1 imbalance in cadmium-induced lung injury and the potential protective effect of astilbin against cadmium-induced lung injury in chicken. Cadmium exposure significantly decreased T-AOC and GSH-Px levels and SOD activity in the chicken lung tissues. In contrast, it significantly increased the MDA and NO levels. These results indicate that cadmium triggers oxidative stress in lungs. Histopathological analysis revealed that cadmium exposure further induced infiltration of lymphocytes in the chicken lungs, indicating that cadmium causes pulmonary damage. Further analysis revealed that cadmium decreased the expression of IL-4 and IL-10 but increased those of IL-17, Foxp3, TNF-α, and TGF-β, indicating that the exposure of cadmium induced the imbalance of Treg/Th1. Moreover, cadmium adversely affected chicken lung function by activating the NF-kB pathway and inducing expression of genes downstream to these pathways (COX-2, iNOS), associated with inflammatory injury in the lung tissue. Astilbin reduced cadmium-induced oxidative stress and inflammation in the lungs by increasing antioxidant enzyme activities and restoring Treg/Th1 balance. In conclusion, our results suggest that astilbin treatment alleviated the effects of cadmium-mediated lung injury in chickens by restoring the Treg/Th1 balance.

Potential therapeutic strategies for osteoarthritis via CRISPR/Cas9 mediated gene editing

Osteoarthritis (OA) is an incapacitating and one of the most common physically degenerative conditions with an assorted etiology and a highly complicated molecular mechanism that to date lacks an efficient treatment. The capacity to design biological networks and accurately modify existing genomic sites holds an apt potential for applications across medical and biotechnological sciences. One of these highly specific genomes editing technologies is the CRISPR/Cas9 mechanism, referred to as the clustered regularly interspaced short palindromic repeats, which is a defense mechanism constituted by CRISPR associated protein 9 (Cas9) directed by small non-coding RNAs (sncRNA) that bind to target DNA through Watson-Crick base pairing rules where subsequent repair of the target DNA is initiated. Up-to-date research has established the effectiveness of the CRISPR/Cas9 mechanism in targeting the genetic and epigenetic alterations in OA by suppressing or deleting gene expressions and eventually distributing distinctive anti-arthritic properties in both in vitro and in vivo osteoarthritic models. This review aims to epitomize the role of this high-throughput and multiplexed gene editing method as an analogous therapeutic strategy that could greatly facilitate the clinical development of OA-related treatments since it's reportedly an easy, minimally invasive technique, and a comparatively less painful method for osteoarthritic patients.

Inhibition of cc chemokine receptor 10 ameliorates osteoarthritis via inhibition of the phosphoinositide-3-kinase/Akt/mammalian target of rapamycin pathway

BACKGROUND

Osteoarthritis (OA) is a joint disease characterized by inflammation and progressive cartilage degradation. Chondrocyte apoptosis is the most common pathological feature of OA. Interleukin-1β (IL-1β), a major inflammatory cytokine that promotes cartilage degradation in OA, often stimulates primary human chondrocytes in vitro to establish an in vitro OA model. Moreover, IL-1β is involved in OA pathogenesis by stimulating the phosphoinositide-3-kinase (PI3K)/Akt and mitogen-activated protein kinases pathways. The G-protein-coupled receptor, cc chemokine receptor 10 (CCR10), plays a vital role in the occurrence and development of various malignant tumors. However, the mechanism underlying the role of CCR10 in the pathogenesis of OA remains unclear. We aimed to evaluate the protective effect of CCR10 on IL-1β-stimulated CHON-001 cells and elucidate the underlying mechanism.

METHODS

The CHON-001 cells were transfected with a control small interfering RNA (siRNA) or CCR10-siRNA for 24 h, and stimulated with 10 ng/mL IL-1β for 12 h to construct an OA model in vitro. The levels of CCR10, cleaved-caspase-3, MMP-3, MMP-13, Collagen II, Aggrecan, p-PI3K, PI3K, p-Akt, Akt, phosphorylated-mammalian target of rapamycin (p-mTOR), and mTOR were detected using quantitative reverse transcription polymerase chain reaction and western blotting. Viability, cytotoxicity, and apoptosis of CHON-001 cells were assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, lactate dehydrogenase assay (LDH), and flow cytometry analysis, respectively. Inflammatory cytokines (TNF-α, IL-6, and IL-8) were assessed using enzyme-linked immunosorbent assay.

RESULTS

Level of CCR10 was substantially higher in the IL-1β-stimulated CHON-001 cells than that in the control group, whereas CCR10 was down-regulated in the CCR10-siRNA transfected CHON-001 cells compared to that in the control-siRNA group. Notably, CCR10 inhibition alleviated IL-1β-induced inflammatory injury in the CHON-001 cells, as verified by enhanced cell viability, inhibited LDH release, reduced apoptotic cells, and cleaved-caspase-3 expression. Meanwhile, IL-1β induced the release of tumor necrosis factor alpha, IL-6, and IL-8, increase of MMP-3 and MMP-13, and decrease of Collagen II and Aggrecan in the CHON-001 cells, which were reversed by CCR10-siRNA. However, these effects were reversed upon PI3K agonist 740Y-P treatment. Further, IL-1β-induced PI3K/Akt/mTOR signaling pathway activation was inhibited by CCR10-siRNA, which was increased by 740Y-P treatment.

CONCLUSION

Inhibition of CCR10 alleviates IL-1β-induced chondrocytes injury via PI3K/Akt/mTOR pathway inhibition, suggesting that CCR10 might be a promising target for novel OA therapeutic strategies.

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.

Protective effect of Danshensu against neurotoxicity induced by monosodium glutamate in adult mice and their offspring

Excessive neuronal excitation by glutamate is a well-established cause of neurotoxicity, leading to severe impairment of brain function. Excitotoxicity is a key factor in numerous neurodegenerative conditions. In this study, we investigated the neuroprotective effects of Danshensu (DSS) against monosodium glutamate (MSG)-induced neurotoxicity in adult mice and their offspring. We randomly divided one hundred 8-week-old Kunming mice (equal number of males and females) into a control group and an experimental group. The experimental group was further subdivided into various treatment groups, including MSG gavage treatment, bwbw DSS treatment group 1 (bwbw DSS treatment group 2, a drug control group, and a normal control group (receiving an equal volume of physiological saline for ten consecutive days). Additionally, another one hundred healthy 8-week-old Kunming mice were similarly divided into groups and treated. These mice were paired randomly (one male and one female) and pregnant females were housed separately to obtain offspring. Subsequently, we conducted histological and behavioral analyses on adult mice and their offspring. MSG treatment induced significant cellular edema and hippocampal damage in both the treated mice and their offspring. However, varying doses of DSS effectively counteracted the neurotoxic effects of MSG, with no adverse impact on brain tissue structure or neural function in either adult mice or their offspring. Behavioral experiments further confirmed that DSS exerted a substantial protective effect against MSG-induced impairment of learning and memory in the treated adult mice and their offspring, in addition to mitigating central nervous system overexcitation and inhibiting exploratory behavior. In conclusion, DSS exerts significant protective effects against MSG-induced neurotoxicity in both adult mice and their offspring.

Network pharmacology integrated with experimental validation revealed the mechanism of Fengshi Gutong Capsule in the treatment of osteoarthritis

ETHNOPHARMACOLOGICAL RELEVANCE

Fengshi Gutong Capsule (FSGTC) is a commonly used Chinese medicine for the treatment of joint pain caused by osteoarthritis (OA). However, the mechanism of action of FSGTC for OA remains unclear.

AIM OF THE STUDY

This study aimed to explore the alleviating effects and potential mechanisms of action of FSGTC for OA through data mining, network pharmacology, and in vitro experiments.

MATERIALS AND METHODS

High-performance liquid chromatography (HPLC) was performed to establish the fingerprints of FSGTC and detect the components of FSGTC absorbed in the blood. The effects of FSGTC on inflammation, immunity, and liver and kidney functions in patients with OA were evaluated by mining clinical data. The potential targets and pathways of FSGTC were screened using network pharmacology. Subsequently, CCK-8 assay, flow cytometry, western blotting, RT-qPCR, ELISA, and immunofluorescence were performed in IL-1β-stimulated chondrocytes for further validation.

RESULTS

Eighty-seven common peaks and 10 components were identified using the HPLC fingerprints of 12 batches of samples, and the similarity was in the range of 0.973-0.998. Retrospective clinical analysis demonstrated a significant reduction in inflammatory response levels among patients with OA who received FSGTC treatment. Network pharmacology analysis revealed that FSGTC potentially targeted processes related to inflammation, oxidative stress, and apoptosis. The phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT), The nuclear factor-κB (NF-κB), and janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathways were predicted to be the main pathways involved in the therapeutic effects of FSGTC in OA. In vitro, FSGTC-containing serum aided the proliferation of chondrocytes stimulated by IL-1β, while concurrently mitigating apoptosis, suppressing the expression of inflammatory cytokines and oxidative molecules, and inhibiting the degradation of the chondrocyte extracellular matrix (ECM).

CONCLUSIONS

FSGTC alleviates the inflammatory response in patients with OA. This therapeutic effect was attributed to its anti-inflammatory and antioxidant properties, and its ability to promote IL-1β-induced chondrocyte proliferation, inhibit apoptosis, and prevent the degradation of extracellular matrix. These favorable results were associated with the inhibition of the PI3K/AKT, NF-κB, and JAK2/STAT3 signaling pathways.

Harpagide inhibits the TNF-α-induced inflammatory response in rat articular chondrocytes by the glycolytic pathways for alleviating osteoarthritis

Osteoarthritis (OA) causes severe and functional dysfunction due to abnormal inflammation. The objective of this study was to evaluate the effect of Harpagide (HPG) on TNF-α-induced inflammation in vitro and in vivo. The effect of HPG on the proliferation of rat chondrocytes was studied. The anti-inflammatory effect of HPG and its molecular mechanisms were elucidated by qPCR, Western blotting, flow cytometry, metabolome analysis in vitro. In addition, the OA rat model was established, and the effect of HPG on OA was verified in vivo. We revealed 10 μM HPG demonstrated biocompatibility. The results demonstrated that HPG restored the upregulation of MMP-13, COX2, IL-1β and IL-6 induced by TNF-α. Moreover, HPG reversed TNF-α induced degradation of the extracellular matrix of chondrocytes. TNF-α treatment induced down-regulation of the mRNA/protein levels of proliferative markers Bcl2, CDK1 and Cyclin D1 were also recovered. HPG can inhibit TNF-α-induced inflammatory response through glycolytic metabolic pathways. HPG can restore TNF-α-induced upregulation of GRP78/IRE1α, and downregulation of AMPK proteins. In vivo experiments demonstrated that after HPG treatment, the appearance and physiological structure of articular cartilage were more integrated with highly organized chondrocytes and rich cartilage matrix compared with OA group. Finally, the molecular docking of HPG and selected key factors in glycolysis results showed that HPG had good binding potential with PFKM, PFKP, PFKFB3, PKM, HK2, and PFKL. In conclusion, the results shown HPG protects and activates chondrocytes, inhibits TNF-α-induced inflammatory response by glycolysis pathway in rat articular chondrocytes, and plays a role in the treatment of OA.

Danggui-Shaoyao-San (DSS) ameliorates the progression of osteoarthritis via suppressing the NF-κB signaling pathway: an in vitro and in vivo study combined with bioinformatics analysis

BACKGROUND

Osteoarthritis (OA) is a common chronic age-related joint disease characterized primarily by inflammation of synovial membrane and degeneration of articular cartilage. Accumulating evidence has demonstrated that Danggui-Shaoyao-San (DSS) exerts significant anti-inflammatory effects, suggesting that it may play an important role in the treatment of knee osteoarthritis (KOA).

METHODS

In the present study, DSS was prepared and analyzed by high-performance liquid chromatography (HPLC). Bioinformatics analyses were carried out to uncover the functions and possible molecular mechanisms by which DSS against KOA. Furthermore, the protective effects of DSS on lipopolysaccharide (LPS)-induced rat chondrocytes and cartilage degeneration in a rat OA model were investigated in vivo and in vitro.

RESULTS

In total, 114 targets of DSS were identified, of which 60 candidate targets were related to KOA. The target enrichment analysis suggested that the NF-κB signaling pathway may be an effective mechanism of DSS. In vitro, we found that DSS significantly inhibited LPS-induced upregulation of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-6 (IL-6), matrix metalloproteinase-3 (MMP3), and matrix metalloproteinase-13 (MMP13). Meanwhile, the degradation of collagen II was also reversed by DSS. Mechanistically, DSS dramatically suppressed LPS-induced activation of the nuclear factor kappa B (NF-κB) signaling pathway. In vivo, DSS treatment prevented cartilage degeneration in a rat OA model.

CONCLUSIONS

DSS could ameliorate the progression of OA through suppressing the NF-κB signaling pathway. Our findings indicate that DSS may be a promising therapeutic approach for the treatment of KOA.

Dangui Huoxue Preparation (DHP) Ameliorates Skin Fibrosis, Inflammation, and Vasculopathy in the Bleomycin-Induced Murine Model of Systemic Sclerosis

Systemic sclerosis (SSc) is an immune-mediated rheumatic disease that is characterized by fibrosis of the skin and internal organs and vasculopathy with poor prognosis. Dangui Huoxue Preparation (DHP) is a clinically effective traditional Chinese herbal formula for the treatment of SSc in the hospital. This study aims to investigate the therapeutic effects and underlying molecular mechanisms of DHP in the treatment of SSc. SSc mice models are induced by bleomycin (BLM). Tissues of DHP group, normal control group, and positive control drug Sanqi Tongshu Capsule (STC) group are collected for inflammation, fibrosis, and vasculopathy. Also, the human dermal fibroblasts (HDF) stimulated with TGF-β1 are analyzed for in vitro study. The expression levels of MCP-1, IFN-γ, IL-1β, IL-10, Fizz1, iNOS, and IL12p40, and the mRNA levels of Col1a1, Col1a2, Col3a1, and Col5a1 are significantly decreased in all DHP groups and STC group compare with those in the BLM group. The main drug of DHP inhibits the proliferation and migration of HDF, reduces Ctgf, Itgb3, Itgb5 expression, and also inhibits the Smad3 pathway. In conclusion, DHP can ameliorate SSc skin inflammation, fibrosis, and vasculopathy, possibly suppressing the TGF-β1/Smad3 signaling pathway through extracellular and intracellular mechanisms.

PLXNC1 interference alleviates the inflammatory injury, apoptosis and extracellular matrix degradation of IL-1β-exposed chondrocytes via suppressing GRP78 expression

BACKGROUND

Osteoarthritis (OA) is a frequently encountered debilitating joint disorder. Whether plexin C1 (PLXNC1) is implicated in OA is far from being investigated despite its well-documented pro-inflammatory property in human diseases. The goal of this study is to expound the specific role of PLXNC1 in OA and elaborate the probable action mechanism.

METHODS

Firstly, PLXNC1 expression in the cartilage tissues of patients with OA was examined with GEO database. In interleukin-1beta (IL-1β)-induced OA cell model, RT-qPCR and western blotting tested the expression of PLXNC1, glucose-regulating protein 78 (GRP78) and extracellular matrix (ECM) degradation-related factors. Cell viability and inflammation were respectively judged by CCK-8 assay and RT-qPCR. TUNEL and western blotting estimated cell apoptosis. The potential binding between PLXNC1 and GRP78 was corroborated by Co-IP assay. Western blotting also tested the expression of endoplasmic reticulum stress (ERS)-associated proteins.

RESULTS

As it turned out, PLXNC1 expression was elevated in the cartilage tissues of patients with OA and IL-1β-treated chondrocytes. When PLXNC1 was depleted, the viability injury, inflammation, apoptosis and ECM degradation of chondrocytes exposed to IL-1β were obstructed. Besides, GRP78 bond to PLXNC1 in IL-1β-treated chondrocytes. The ascending GRP78 expression in the chondrocytes exposed to IL-1β was depleted after PLXNC1 was silenced. Meanwhile, the impacts of PLXNC1 deficiency on the viability, inflammatory response, apoptosis, ECM degradation as well as ERS in IL-1β-exposed chondrocytes were abolished by GRP78 up-regulation.

CONCLUSION

In summary, PLXNC1 silencing might interact with and down-regulate GRP78 to mitigate the apoptosis, inflammation, and ECM degradation of IL-1β-insulted chondrocytes in OA.

Ubiquitin-specific peptidase 25 exacerbated osteoarthritis progression through facilitating TXNIP ubiquitination and NLRP3 inflammasome activation

Several members of the ubiquitin-specific proteases (USPs) family have been revealed to regulate the progression of osteoarthritis (OA). The current study aimed to investigate the role and the underlying mechanism of USP25 in IL-1β-induced chondrocytes and OA rat model. It was discovered that IL-1β stimulation upregulated USP25, increased ROS level, and suppressed cell viability in rat chondrocytes. Besides, USP25 knockdown alleviated IL-1β-induced injury by decreasing ROS level, attenuating pyroptosis, and downregulating the expression of IL-18, NLRP3, GSDMD-N, active caspase-1, MMP-3, and MMP-13. Furthermore, we discovered that USP25 affected the IL-1β-induced injury in chondrocytes in a ROS-dependent manner. Moreover, USP25 was revealed to interact with TXNIP, and USP25 knockdown increased the ubiquitination of TXNIP. The pro-OA effect of USP25 abundance could be overturned by TXNIP suppression in IL-1β-induced chondrocytes. Finally, in vivo experiment results showed that USP25 inhibition alleviated cartilage destruction in OA rats. In conclusion, we demonstrated that USP25 stimulated the overproduction of ROS to activate the NLRP3 inflammasome via regulating TXNIP, resulting in increased pyroptosis and inflammation in OA.

Human umbilical cord mesenchymal stem cells-derived exosomes exert anti-inflammatory effects on osteoarthritis chondrocytes

Inflammation of chondrocytes plays a critical role in the occurrence and development of osteoarthritis (OA). Recent evidence indicated exosomes derived from mesenchymal stem cells (MSCs-Exos) exhibit excellent anti-inflammatory ability in many troublesome inflammatory diseases including OA. In the present study, we aimed to explore the role of human umbilical cord-derived MSCs-Exos (hUC-MSCs-Exos) in treating the inflammation of chondrocytes and its related mechanisms. Ultracentrifugation was applied to isolate hUC-MSCs-Exos from the culture supernatant of hUC-MSCs. Two OA-like in vitro inflammation models of human articular chondrocytes induced with interleukin 1β (IL-1β) and co-incubation with macrophage utilizing transwell cell culture inserts were both used to evaluate the anti-inflammatory effects of hUC-MSCs-Exos. The mRNA sequencing of chondrocytes after treatment and microRNA (miRNA) sequencing of hUC-MSCs-Exos were detected and analyzed for possible mechanism analysis. The results of the study confirmed that hUC-MSCs-Exos had a reversed effect of IL-1β on chondrocytes in the expression of collagen type II alpha 1 (COL2A1) and matrix metalloproteinase 13 (MMP13). The addition of hUC-MSCs-Exos to M1 macrophages in the upper chamber showed down-regulation of IL-1β and tumor necrosis factor α (TNF-α), up-regulation of IL-10 and arginase1 (ARG1), and reversed the gene and protein expression of COL2A1 and MMP13 of the chondrocytes seeded in the lower chamber. The results of this study confirmed the anti-inflammatory effects of hUC-MSCs-Exos in the human articular chondrocytes inflammation model. hUC-MSCs-Exos may be used as a potential cell-free treatment strategy for chondrocyte inflammation in OA.

Sodium Danshensu stabilizes atherosclerotic vulnerable plaques by targeting IKKβ mediated inflammation in macrophages

BACKGROUND

The primary cause of acute cardiovascular events with high mortality is the rupture of atherosclerotic plaque followed by thrombosis. Sodium Danshensu (SDSS) has shown potential in inhibiting the inflammatory response in macrophages and preventing early plaque formation in atherosclerotic mice. However, the specific targets and detailed mechanism of action of SDSS are still unclear.

OBJECTIVE

This study aims to investigate the efficacy and mechanism of SDSS in inhibiting inflammation in macrophages and stabilizing vulnerable plaques in atherosclerosis (AS).

MATERIALS AND METHODS

The efficacy of SDSS in stabilizing vulnerable plaques was demonstrated using various techniques such as ultrasound, Oil Red O staining, HE staining, Masson staining, immunohistochemistry, and lipid analysis in ApoE-/- mice. Subsequently, IKKβ was identified as a potential target of SDSS through protein microarray, network pharmacology analysis, and molecular docking. Additionally, ELISA, RT-qPCR, Western blotting, and immunofluorescence were employed to measure the levels of inflammatory cytokines, IKKβ, and NF-κB pathway-related targets, thereby confirming the mechanism of SDSS in treating AS both in vivo and in vitro. Finally, the impact of SDSS was observed in the presence of an IKKβ-specific inhibitor.

RESULTS

Initially, the administration of SDSS led to a decrease in the formation and area of aortic plaque, while also stabilizing vulnerable plaques in ApoE-/- mice. Furthermore, it was identified that IKKβ serves as the primary binding target of SDSS. Additionally, both in vivo and in vitro experiments demonstrated that SDSS effectively inhibits the NF-κB pathway by targeting IKKβ. Lastly, the combined use of the IKKβ-specific inhibitor IMD-0354 further enhanced the beneficial effects of SDSS.

CONCLUSIONS

SDSS stabilized vulnerable plaques and suppressed inflammatory responses by inhibiting the NF-κB pathway through its targeting of IKKβ.

Pelargonidin ameliorates inflammatory response and cartilage degeneration in osteoarthritis via suppressing the NF-κB pathway

Pelargonidin (PG), a derivative of anthocyanins, has anti-oxidant and anti-inflammatory properties. Herein, the protective effect and the mechanism of PG in counteract the osteoarthritis (OA) progression were needed to further evaluate. In the current study, C57BL/6 mice was induced by destabilization of medial meniscus (DMM) surgery to establish the OA model. Primary chondrocytes were acquired from the knee cartilage of newborn mice. Then, PG was administrated to OA mice and IL-1β-stimulated chondrocytes to evaluate its protective effects, respectively. Results uncovered that no conspicuous cytotoxic effects were observed when chondrocytes were treated with PG at a concentration lower than 40 μM for 24-72h. Thus, 10 μM, 20 μM, and 40 μM PG were chosen for subsequent experiments in vitro. Then, we observed that 10, 20, and 40 μM PG reduced the levels of IL-6, TNF-α, COX-2 and iNOS in chondrocytes. In line, PG inhibited the IL-1β-induced ECM catabolism in chondrocytes, as evidenced by deepening toluidine blue staining, increased expression of Collagen II, and decreased expressions of ADAMTS5 and MMP13. Moreover, PG also reduced the IL-1β-stimulated p-p65 overexpression and nuclear translocation of p65 in chondrocytes. In vivo, Safranin O/Fast green and HE staining showed that articular cartilage surface morphology was basically smooth and complete after PG treatment for 8 weeks. Similarly, OARSI scores and MMP13 expression were apparently decreased, whereas Aggrecan expression was elevated in PG-treated mice 8 weeks after DMM surgery. In conclusion, PG can effectively ameliorate inflammatory reactions and cartilage degeneration via suppressing the NF-κB pathway, thereby restraining the OA progression.

Extracts of Oldenlandia diffusa protects chondrocytes via inhibiting apoptosis and associated inflammatory response in osteoarthritis

ETHNOPHARMACOLOGICAL RELEVANCE

Osteoarthritis (OA) is a type of joint disorder that is marked by the gradual breakdown of cartilage and persistent inflammation of the synovial membrane, and is a leading cause of disability among elderly people worldwide. Oldenlandia diffusa (OD) is a member of the Rubiaceae family, and various researches have revealed that it possesses antioxidant, anti-inflammatory, and anti-tumor properties.Extracts of Oldenlandia diffusa is commonly used in traditional oriental medicine to treat various illnesses, including inflammation and cancer.

AIM OF THE STUDY

This study is aimed at investigating the anti-inflammatory and anti-apoptosis effects of OD and its potential mechanisms on IL-1β-induced mouse chondrocytes, as well as its characteristics in a mouse osteoarthritis model.

MATERIALS AND METHODS

In this study, the key targets and potential pathways of OD were determined through network pharmacology analysis and molecular docking. The potential mechanism of OD in osteoarthritis was verified by in vitro and in vivo studies.

RESULTS

The results of network pharmacology showed that Bax, Bcl2, CASP3, and JUN are key candidate targets of OD for the treatment of osteoarthritis. There is a strong correlation between apoptosis and both OA and OD. Additionally, molecular docking results show that β-sitosterol in OD can strongly bind with CASP3 and PTGS2. In vitro experiments showed that OD pretreatment inhibited the expression of pro-inflammatory factors induced by IL-1β, such as COX2, iNOS, IL-6, TNF-α, and PGE2. Furthermore, OD reversed IL-1β-mediated degradation of collagen II and aggrecan within the extracellular matrix (ECM). The protective effect of OD can be attributed to its inhibition of the MAPK pathway and inhibition of chondrocyte apoptosis. Additionally, it was found that OD can alleviate cartilage degradation in a mouse model of knee osteoarthritis.

CONCLUSION

Our study showed that β-sitosterol, one of the active components of OD, could alleviate the inflammation and cartilage degeneration of OA by inhibiting chondrocyte apoptosis and MAPK pathway.

Research progress and hot spot analysis related to oxidative stress and osteoarthritis: a bibliometric analysis

BACKGROUND

Osteoarthritis, a common degenerative osteochondral disease, has a close relationship between its mechanism of occurrence and oxidative stress. However, there are relatively few relevant studies in this field, and a more mature research system has not yet been formed.

METHODS

By searching the Web of Science (WOS) database, we obtained 1 412 publications in the field of osteoarthritis and oxidative stress. The search results were then analyzed bibliometrically using Citespace and VOSviewer, including a study of publication trends in the field, analysis of core authors, analysis of countries and institutions with high contributions, analysis of core journals, and to identify research trends and hot spots in the field, we performed keyword clustering.

RESULTS

We collected 1 412 publications on the field of osteoarthritis and oxidative stress from 1998-2022. By analyzing the publication trends in the field, we noted an exponential increase in the number of publications per year since 2014. We then identified the core authors in the field (Blanco, Francisco J., Loeser, Richard F., Vaamonde-garcia, et.al) as well as the countries (China, USA, Italy et.al) and institutions (Xi An Jiao Tong Univ, Wenzhou Med Univ, Zhejiang Univ et.al). The OSTEOARTHRITIS AND CARTILAGE and INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES contain a large number of research papers in this field, and through keyword co-occurrence analysis, we counted 3 227 keywords appearing in the field of osteoarthritis and oxidative stress. These keywords were clustered into 9 groups, representing 9 different research hotspots.

CONCLUSIONS

Research in the field of osteoarthritis and oxidative stress has been developing since 1998 and is now maturing, but there is an urgent need to strengthen international academic exchanges and discuss the future focus of research development in the field of osteoarthritis and oxidative stress.

Dihydrocaffeic acid improves IL-1β-induced inflammation and cartilage degradation via inhibiting NF-κB and MAPK signalling pathways

Aims

Osteoarthritis (OA) is a prevalent joint disorder with inflammatory response and cartilage deterioration as its main features. Dihydrocaffeic acid (DHCA), a bioactive component extracted from natural plant (gynura bicolor), has demonstrated anti-inflammatory properties in various diseases. We aimed to explore the chondroprotective effect of DHCA on OA and its potential mechanism.

Methods

In vitro, interleukin-1 beta (IL-1β) was used to establish the mice OA chondrocytes. Cell counting kit-8 evaluated chondrocyte viability. Western blotting analyzed the expression levels of collagen II, aggrecan, SOX9, inducible nitric oxide synthase (iNOS), IL-6, matrix metalloproteinases (MMPs: MMP1, MMP3, and MMP13), and signalling molecules associated with nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways. Immunofluorescence analysis assessed the expression of aggrecan, collagen II, MMP13, and p-P65. In vivo, a destabilized medial meniscus (DMM) surgery was used to induce mice OA knee joints. After injection of DHCA or a vehicle into the injured joints, histological staining gauged the severity of cartilage damage.

Results

DHCA prevented iNOS and IL-6 from being upregulated by IL-1β. Moreover, the IL-1β-induced upregulation of MMPs could be inhibited by DHCA. Additionally, the administration of DHCA counteracted IL-1β-induced downregulation of aggrecan, collagen II, and SOX9. DHCA protected articular cartilage by blocking the NF-κB and MAPK pathways. Furthermore, DHCA mitigated the destruction of articular cartilage in vivo.

Conclusion

We present evidence that DHCA alleviates inflammation and cartilage degradation in OA chondrocytes via suppressing the NF-κB and MAPK pathways, indicating that DHCA may be a potential agent for OA treatment.

Cite this article: Bone Joint Res 2023;12(4):259–273.

Using Microphysiological System for the Development of Treatments for Joint Inflammation and Associated Cartilage Loss-A Pilot Study

Osteoarthritis (OA) is a painful and disabling joint disease affecting millions worldwide. The lack of clinically relevant models limits our ability to predict therapeutic outcomes prior to clinical trials, where most drugs fail. Therefore, there is a need for a model that accurately recapitulates the whole-joint disease nature of OA in humans. Emerging microphysiological systems provide a new opportunity. We recently established a miniature knee joint system, known as the miniJoint, in which human bone-marrow-derived mesenchymal stem cells (hBMSCs) were used to create an osteochondral complex, synovial-like fibrous tissue, and adipose tissue analogs. In this study, we explored the potential of the miniJoint in developing novel treatments for OA by testing the hypothesis that co-treatment with anti-inflammation and chondroinducing agents can suppress joint inflammation and associated cartilage degradation. Specifically, we created a "synovitis"-relevant OA model in the miniJoint by treating synovial-like tissues with interleukin-1β (IL-1β), and then a combined treatment of oligodeoxynucleotides (ODNs) suppressing the nuclear factor kappa beta (NF-κB) genetic pathway and bone morphogenic protein-7 (BMP-7) was introduced. The combined treatment with BMP-7 and ODNs reduced inflammation in the synovial-like fibrous tissue and showed an increase in glycosaminoglycan formation in the cartilage portion of the osteochondral complex. For the first time, this study demonstrated the potential of the miniJoint in developing disease-modifying OA drugs. The therapeutic efficacy of co-treatment with NF-κB ODNs and BMP-7 can be further validated in future clinical studies.

Air pollution exposure and auto-inflammatory and autoimmune diseases of the musculoskeletal system: a review of epidemiologic and mechanistic evidence

Auto-inflammatory and autoimmune diseases of the musculoskeletal system can be perceived as a spectrum of rheumatic diseases, with the joints and connective tissues are eroded severely that progressively develop chronic inflammation and lesion. A wide range of risk factors represented by genetic and environmental factors have been uncovered by population-based surveys and experimental studies. Lately, the exposure to air pollution has been found to be potentially involved in the mechanisms of occurrence or development of such diseases, principally manifest in oxidative stress, local and systemic inflammation, and epigenetic modifications, as well as the mitochondrial dysfunction, which has been reported to participate in the intermediate links. The lungs might serve as a starting area of air pollutants, which would cause oxidative stress-induced bronchial-associated lymphoid tissue (iBALT) to further to influence T, B cells, and the secretion of pro-inflammatory cytokines. The binding of aromatic hydrocarbon receptor (AhR) to the corresponding contaminant ligands tends to regulate the reaction of Th17 and Tregs. Furthermore, air pollution components might spur on immune and inflammatory responses by damaging mitochondria that could interact with and exacerbate oxidative stress and pro-inflammatory cytokines. In this review, we focused on the association between air pollution and typical auto-inflammatory and autoimmune diseases of the musculoskeletal system, mainly including osteoarthritis (OA), rheumatoid arthritis (RA), spondyloarthritis (SpA) and juvenile idiopathic arthritis (JIA), and aim to collate the mechanisms involved and the potential channels. A complete summary and in-depth understanding of the autoimmune and inflammatory effects of air pollution exposure should hopefully contribute new perspectives on how to formulate better public health policies to alleviate the adverse health effects of air pollutants.

Transcriptome profiling Revealed the potential mechanisms of Shen Lin Bai Zhu San n-butanol extract on DSS induced Colitis in Mice and LC-MS analysis

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic and recurrent inflammatory disorder in gastrointestinal tract. Shen Ling Bai Zhu San (SLBZS), which has a long history of use in Traditional Chinese Medicine (TCM), has been widely used to treat gastrointestinal diseases. The isolated fractions of TCM have also been proved to possess an important potential for treating diseases, which are due to their effective components.

PURPOSE

In this study, we examined the possibility that SLBZS and its isolated active fractions may prevent DSS-induced colitis, and investigated the potential mechanisms by regulating genetic profile of colon.

METHODS

Colitis mice were induced by 2.5% DSS for 7 days, and then SLBZS and different SLBZS extracts were administrated to protect the mice for 7 days. Body weight, diarrhea, bleeding in stool, colon length, spleen weight, cytokines of serum and colon and pathology of colon were assessed. The level of Ginsenoside Rg1, Re and Rb1 in different SLBZS extracts and qualitative analysis of n-butanol extract of SLBZS (S-Nb) was performed by HPLC and LC-MS, respectively. And the effects of S-Nb on the transcriptome in colitis were investigated.

RESULTS

Our results showed that SLBZS and S-Nb significantly regained body weight, reduced DAI, splenomegaly and the length of colon and attenuated histological damage of the colon. Meanwhile, SLBZS and S-Nb markedly reduced the levels of TNF-α, IL-1β and IL-6 and increased the level of IL-10 in serum and colon. These effects may be associated with the high levels of Ginsenoside Rg1, Re and Rb1 and rich variety of compounds in S-Nb including 6 ginsenosides, glycyrrhizin, L-tryptophan, and so on. Transcriptome analysis revealed that S-Nb selectively regulated 103 differentially expressed genes (DEGs), 36 of which were changed in DSS-induced mice. And the genes of Per2, Per3, Npy and Serpina3m were closely related to colitis and also restored by S-Nb with different extent. Remarkably, these DEGs modulated the biological functions of colitis mice, including extracellular region, response to external stimulus, MAPK signaling pathway and arginine and proline metabolism.

CONCLUSIONS

These data indicated that SLBZS and S-Nb blunted DSS-induced colitis by modulating differentially expression gene profile and biological functions based on their ginsenosides and rich compounds.

Calycosin mitigates chondrocyte inflammation and apoptosis by inhibiting the PI3K/AKT and NF-κB pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Shaoyao Gancao Decoction (SG-Tang), originated from the Treatise on Febrile Diseases, is often used to treat OA pain symptoms. Whereas its efficacy has been verified by several clinical studies, the underlying mechanism remained unclear. Network pharmacology and UPLC-QTOF-MS analysis found that calycosin could be regarded as the active components of SG-Tang in treating OA. However, the effect of calycosin on cartilage destruction and the pathogenesis of OA are not known. Therefore, we evaluated the benefits of calycosin for OA and revealed the underlying mechanisms.

AIM OF STUDY

Using network pharmacology, UPLC-QTOF-MS analysis and experiments, the active components of SG-Tang were analyzed to explore their potential therapeutic mechanism in OA.

MATERIALS AND METHODS

The components of SG-Tang were detected by UPLC-QTOF-MS, and the possible active components and mechanism of SG-Tang in the treatment of OA were screened by network pharmacology. The OA mouse model was constructed by DMM. In total, 30 mice were randomly divided into three groups: Sham, DMM, and DMM + Calycosin. H&E, safranin O/fast green staining and the OARSI scores were used to evaluate joint injury in mice. In addition, OA models were established using chondrocytes treated with 10 ng/mL IL-1β. Treatment groups were treated with 100, 200 or 400 μM calycosin. CCK-8 assay was used for assessing the cytotoxic effects of calycosin. TUNEL staining and Western blotting were used to detect chondrocyte apoptosis. In addition, PI3K/Akt and NF-κB signaling pathway-related markers and cartilage matrix-related indicators were also detected.

RESULTS

In vivo studies showed that calycosin inhibited IL-1β-induced IL-6 and TNF-α production, as well as iNOS and COX-2 expression. Meanwhile, calycosin could inhibit IL-1β-induced degradation of cartilage matrix, including downregulation of MMP3, MMP-13, collagen II and aggrecan. NF-κB and PI3K/AKT were also inhibited by calycosin in OA chondrocytes. Furthermore, calycosin inhibited IL-1β-induced apoptosis in mouse chondrocytes. In a mouse model of OA, our results suggest that calycosin has a chondroprotective effect.

CONCLUSIONS

According to this study, calycosin may act as a protective agent against OA by inhibiting the PI3K/AKT and NF-κB pathways. Furthermore, this study suggested that calycosin is a potential candidate for the treatment of OA.

Shear-responsive boundary-lubricated hydrogels attenuate osteoarthritis

Lipid-based boundary layers formed on liposome-containing hydrogels can facilitate lubrication. However, these boundary layers can be damaged by shear, resulting in decreased lubrication. Here, a shear-responsive boundary-lubricated drug-loaded hydrogel is created by incorporating celecoxib (CLX)-loaded liposomes within dynamic covalent bond-based hyaluronic acid (HA) hydrogels (CLX@Lipo@HA-gel). The dynamic cross-linked network enables the hydrogel to get restructured in response to shear, and the HA matrix allows the accumulation of internal liposome microreservoirs on the sliding surfaces, which results in the formation of boundary layers to provide stable lubrication. Moreover, hydration shells formed surrounding the hydrogel can retard the degradation process, thus helping in sustaining lubrication. Furthermore, in vitro and in vivo experiments found that CLX@Lipo@HA-gels can maintain anabolic-catabolic balance, alleviate cartilage wear, and attenuate osteoarthritis progression by delivering CLX and shear-responsive boundary lubrication. Overall, CLX@Lipo@HA-gels can serve as shear-responsive boundary lubricants and drug-delivery vehicles to alleviate friction-related diseases like osteoarthritis.

Oxymatrine Protects Chondrocytes against IL-1β-triggered Apoptosis in Vitro and Inhibits Osteoarthritis in Mice Model

Background

Osteoarthritis (OA) is a multifactorial disease with various risk factors, resulting in the degeneration of articular cartilage and whole joints. However, to date, no effective disease-modifying therapy for OA has been developed. Oxymatrine (OMT) is associated with many pharmacological effects, including anti-inflammatory, antiapoptotic, and antioxidative properties. However, the role of OMT in OA remains unclear.

Materials and Methods

An IL-1β-induced chondrocyte model and anterior cruciate ligament transection (ACLT)-induced murine model of OA were constructed. The effect of OMT on chondrocyte viability was assessed using the CCK-8 assay. The protein level was assessed by Western blot analysis, and the apoptosis rate was assessed by flow cytometry in vitro and TUNEL staining in OA model mice. The effect of OMT on the degradation of articular cartilage in ACLT-induced OA mice was assessed by histological analysis.

Results

OMT at 0–2 mg/mL showed no conspicuous cytotoxicity on chondrocytes after 24 hours of incubation. OMT at 0.5, 1, and 2 mg/mL inhibited IL-1β-triggered apoptosis, upregulated MMP13, MMP9, and Col X, and upregulated Col II in chondrocytes in vitro. OMT represses the NF-κB signaling cascade in IL-1β-triggered chondrocytes in vitro. In an in vivo study, OMT decreased the apoptosis rate of chondrocytes and exerted a protective effect against the degradation of articular cartilage in ACLT-triggered OA mice.

Conclusion

OMT plays a protective role against chondrocyte injury induced by IL-1β in vitro or ACLT in vivo. OMT may play a role in chondrocytes during OA by inhibiting NF-κB signaling by decreasing the phosphorylation of p65 and IκB. OMT treatment may be a promising chondroprotective approach to delay OA cartilage progression.

Pyroptosisin periodontitis: From the intricate interaction with apoptosis, NETosis, and necroptosis to the therapeutic prospects

Periodontitis is highly prevalent worldwide. It is characterized by periodontal attachment and alveolar bone destruction, which not only leads to tooth loss but also results in the exacerbation of systematic diseases. As such, periodontitis has a significant negative impact on the daily lives of patients. Detailed exploration of the molecular mechanisms underlying the physiopathology of periodontitis may contribute to the development of new therapeutic strategies for periodontitis and the associated systematic diseases. Pyroptosis, as one of the inflammatory programmed cell death pathways, is implicated in the pathogenesis of periodontitis. Progress in the field of pyroptosis has greatly enhanced our understanding of its role in inflammatory diseases. This review first summarizes the mechanisms underlying the activation of pyroptosis in periodontitis and the pathological role of pyroptosis in the progression of periodontitis. Then, the crosstalk between pyroptosis with apoptosis, necroptosis, and NETosis in periodontitis is discussed. Moreover, pyroptosis, as a novel link that connects periodontitis with systemic disease, is also reviewed. Finally, the current challenges associated with pyroptosis as a potential therapeutic target for periodontitis are highlighted.

Inhibition of GAB2 expression has a protective effect on osteoarthritis:An in vitro and in vivo study

Osteoarthritis is a chronic age-related degenerative disease associated with varying degrees of pain and joint mobility disorders. Grb2-associated-Binding protein-2 (GAB2) is an intermediate molecule that plays a role downstream in a variety of signaling pathways, such as inflammatory signaling pathways. The role of GAB2 in the pathogenesis of OA has not been fully studied. In this study, we found that GAB2 expression was elevated in chondrocytes after constructing in vivo and in vitro models of OA. Inhibition of GAB2 by siRNA decreased the expression of MMP3, MMP13, iNOS, COX2, p62, and increased the expression of COL2, SOX9, ATG7, Beclin-1 and LC3II/LC3I. Furthermore, inhibition of GAB2 expression inhibited interleukin-1β (IL-1β) -induced mitogen-activated protein kinase (MAPK) and nuclear factor κB (NF-κB) signaling. In vivo studies, we found that reduced GAB2 expression effectively delayed cartilage destruction in a mouse model of OA induced by destabilisation of the medial meniscus (DMM). In conclusion, our study demonstrates that GAB2 is a potential therapeutic target for OA.

Anti-Inflammatory Effect of Sulfated Polysaccharides Isolated from Codium fragile In Vitro in RAW 264.7 Macrophages and In Vivo in Zebrafish

In this study, the anti-inflammatory activity of sulfated polysaccharides isolated from the green seaweed Codium fragile (CFCE-PS) was investigated in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and zebrafish. The results demonstrated that CFCE-PS significantly increased the viability of LPS-induced RAW 264.7 cells in a concentration-dependent manner. CFCE-PS remarkably and concentration-dependently reduced the levels of inflammatory molecules including prostaglandin E₂, nitric oxide (NO), interleukin-1 beta, tumor necrosis factor-alpha, and interleukin-6 in LPS-stimulated RAW 264.7 cells. In addition, in vivo test results indicated that CFCE-PS effectively reduced reactive oxygen species, cell death, and NO levels in LPS-stimulated zebrafish. Thus, these results indicate that CFCE-PS possesses in vitro and in vivo anti-inflammatory activities and suggest it is a potential ingredient in the functional food and pharmaceutical industries.

Bioinformatics-Led Discovery of Osteoarthritis Biomarkers and Inflammatory Infiltrates

The molecular mechanisms of osteoarthritis, the most common chronic disease, remain unexplained. This study aimed to use bioinformatic methods to identify the key biomarkers and immune infiltration in osteoarthritis. Gene expression profiles (GSE55235, GSE55457, GSE77298, and GSE82107) were selected from the Gene Expression Omnibus database. A protein-protein interaction network was created, and functional enrichment analysis and genomic enrichment analysis were performed using the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genome (KEGG) databases. Immune cell infiltration between osteoarthritic tissues and control tissues was analyzed using the CIBERSORT method. Identify immune patterns using the ConsensusClusterPlus package in R software using a consistent clustering approach. Molecular biological investigations were performed to discover the important genes in cartilage cells. A total of 105 differentially expressed genes were identified. Differentially expressed genes were enriched in immunological response, chemokine-mediated signaling pathway, and inflammatory response revealed by the analysis of GO and KEGG databases. Two distinct immune patterns (ClusterA and ClusterB) were identified using the ConsensusClusterPlus. Cluster A patients had significantly lower resting dendritic cells, M2 macrophages, resting mast cells, activated natural killer cells and regulatory T cells than Cluster B patients. The expression levels of TCA1, TLR7, MMP9, CXCL10, CXCL13, HLA-DRA, and ADIPOQSPP1 were significantly higher in the IL-1β-induced group than in the osteoarthritis group in an in vitro qPCR experiment. Explaining the differences in immune infiltration between osteoarthritic tissues and normal tissues will contribute to the understanding of the development of osteoarthritis.

Harpagophytum procumbens Root Extract Mediates Anti-Inflammatory Effects in Osteoarthritis Synoviocytes through CB2 Activation

The endocannabinoid system is involved in the nociceptive and anti-inflammatory pathways, and a lowered expression of CB2 receptors has been associated with inflammatory conditions, such as osteoarthritis (OA). This suggests that CB2 modulators could be novel therapeutic tools to treat OA. In the present study, the involvement of Harpagophytum procumbens root extract, a common ingredient of nutraceuticals used to treat joint disorders, in CB2 modulation has been evaluated. Moreover, to clarify the effects of the pure single components, the bioactive constituent, harpagoside, and the main volatile compounds were studied alone or in a reconstituted mixture. Human fibroblast-like synoviocytes, extracted by joints of patients, who underwent a total knee replacement, were treated with an H. procumbens root extract dissolved in DMSO (HPE_DMSO). The effectiveness of HPE_DMSO to affect CB2 pathways was studied by analyzing the modulation of cAMP, the activation of PKA and ERK MAP kinase, and the modulation of MMP-13 production. HPE_DMSO was able to inhibit the cAMP production and MAP kinase activation and to down-regulate the MMP-13 production. Pure compounds were less effective than the whole phytocomplex, thus suggesting the involvement of synergistic interactions. Present findings encourage further mechanistic studies and support the scientific basis of the use of H. procumbens in joint disorders.

Oroxin B alleviates osteoarthritis through anti-inflammation and inhibition of PI3K/AKT/mTOR signaling pathway and enhancement of autophagy

BACKGROUND

Osteoarthritis (OA) is a common aging-related degenerative joint disease with chronic inflammation as its possible pathogenesis. Oroxin B (OB), a flavonoid isolated from traditional Chinese herbal medicine, possesses anti-inflammation properties which may be involved in regulating the pathogenesis of OA, but its mechanism has not been elucidated. Our study was the first to explore the potential chondroprotective effect and elucidate the underlying mechanism of OB in OA.

METHODS

In vitro, primary mice chondrocytes were stimulated with IL-1β along with or without the administration of OB or autophagy inhibitor 3-methyladenine (3-MA). Cell viability assay was measured with a cell counting kit-8 (CCK-8). The phenotypes of anabolic-related (Aggrecan and Collagen II), catabolic-related (MMP3, MMP13, and ADAMTS5), inflammation-related (iNOS, COX-2, TNF-α, IL-6, and IL-1β), and markers of related signaling pathways in chondrocytes with different treatment were detected through western blot, RT-qPCR, and immunofluorescent staining. In vivo, the destabilized medial meniscus (DMM) operation was performed to establish the OA mice model. After knee intra-articular injection with OB for 8 weeks, the mice's knee joints were obtained for subsequent histological staining and analysis.

RESULTS

OB reversed the expression level of anabolic-related proteins (Aggrecan and Collagen II) and catabolic-related (MMP3, MMP13, and ADAMTS5) in IL-1β-induced chondrocytes. Mechanistically, OB suppressed the inflammatory response stimulated by IL-1β, as the inflammation-related (iNOS, COX-2, TNF-α, IL-6, and IL-1β) markers were downregulated after the administration of OB in IL-1β-induced chondrocytes. Besides, the activation of PI3K/AKT/mTOR signaling pathway induced by IL-1β could be inhibited by OB. Additionally, the autophagy process impaired by IL-1β could be rescued by OB. What's more, the introduction of 3-MA to specifically inhibit the autophagic process impairs the protective effect of OB on cartilage. In vivo, histological staining revealed that intra-articular injection of OB attenuated the cartilage degradation, as well as reversed the expression level of anabolic and catabolic-related proteins such as Aggrecan, Collagen II, and MMP13 induced in DMM-induced OA models.

CONCLUSIONS

The study verified that OB exhibited the chondroprotective effect by anti-inflammatory, inhibiting the PI3K/AKT/mTOR signaling pathway, and enhancing the autophagy process, indicating that OB might be a promising agent for the treatment of OA.