Acteoside inhibits inflammatory response via JAK/STAT signaling pathway in osteoarthritic rats

Mechanisms and applications of the regenerative capacity of platelets-based therapy in knee osteoarthritis

Osteoarthritis (OA) is the most prevalent joint disease in the elderly population and its substantial morbidity and disability impose a heavy economic burden on patients and society. Knee osteoarthritis (KOA) is the most common subtype of OA, which is characterized by damage to progressive articular cartilage, synovitis, and subchondral bone sclerosis. Most current treatments for OA are palliative, primarily aim at symptom management, and do not prevent the progression of the disease or restore degraded cartilage. The activation of α-granules in platelets releases various growth factors that are involved in multiple stages of tissue repair, suggesting potential for disease modification. In recent years, platelet-based therapies, such as platelet-rich plasma, platelet-rich fibrin, and platelet lysates, have emerged as promising regenerative treatments for KOA, but their related effects and mechanisms are still unclear. Therefore, this review aims to summarize the biological characteristics and functions of platelets, classify the products of platelet-based therapy and related preparation methods. Moreover, we summarize the basic research of platelet-based regeneration strategies for KOA and discuss the cellular effects and molecular mechanisms. Further, we describe the general clinical application of platelet-based therapy in the treatment of KOA and the results of the meta-analysis of randomized controlled trials.

METTL14-mediated lncRNA-FAS-AS1 promotes osteoarthritis progression by up-regulating ADAM8

BACKGROUND

Osteoarthritis (OA) is a prevalent degenerative disease. We explored the role and regulatory mechanisms of lncRNA-FAS-AS1 in OA progression.

METHODS

We exposed human immortalized chondrocytes to IL-1β for 24 h to induce an OA cell model. The target molecule levels were assessed using western blot and quantitative real-time PCR (RT-qPCR). Cell viability and apoptosis were measured using CCK-8 and flow cytometry. The m6A modification of FAS-AS1 was determined using MeRIP. We examined the binding relationships between FAS-AS1, Fragile X mental retardation 1 (FMR1), and A disintegrin and metalloproteinase 8 (ADAM8) using RIP and RNA pull-down. The OA animal model was established by separating the medial collateral ligament and medial meniscus. Safranin-O staining and Mankin's scale were employed to evaluate pathological changes within the cartilage.

RESULTS

FAS-AS1, METTL14, and ADAM8 were upregulated, and the JAK/STAT3 signaling pathway was activated in OA mice and IL-1β-induced chondrocytes. FAS-AS1 knockdown inhibited extracellular matrix degradation in IL-1β-induced chondrocytes; however, ADAM8 overexpression reversed this effect. FAS-AS1 maintained the stability of ADAM8 mRNA by recruiting FMR1. METTL14 knockdown repressed FAS-AS1 expression in an m6A-dependent manner. FAS-AS1 overexpression reversed the inhibitory effects of METTL14 knockdown on JAK/STAT3 signaling and cartilage damage in the OA model both in vitro and in vivo.

CONCLUSION

METTL14-mediated FAS-AS1 promotes OA progression through the FMR1/ADAM8/JAK/STAT3 axis.

The involvement of signaling pathways in the pathogenesis of osteoarthritis: An update

Osteoarthritis (OA) is one of the most common disabling pathologies, characterized by joint pain and reduced function, significantly worsening the quality of life. Even if important progresses have been made in OA research, little is yet known about the precise cellular and molecular mechanisms underlying OA. Understanding dysregulated signaling networks and their crosstalk in OA may offer a strong opportunity for the development of combined targeted therapies. Hence, this review highlights the recent findings on the main pathways involved in OA development, including Wnt, Notch, Hedgehog, MAPK, AMPK, and JAK/STAT, providing insights on current targeted therapies in OA patients' management.

The translational potential of this article

The identification of key signaling pathways involved in OA development and the investigation of their signaling crosstalk could pave the way for more effective treatments and improved management of OA patients in the future.

The effects of acteoside on locomotor recovery after spinal cord injury - The role of autophagy and apoptosis signaling pathway

In the current study, we investigated the effects of acteoside as a phenylpropanoid glycoside on interaction with neurons to assesses locomotor recovery after spinal cord injury (SCI) in rats by focusing on evaluating the factors involved in autophagy, apoptosis, inflammation and oxidative stress processes. 49 Spargue-Dawley rats were prepared and divided into seven healthy and SCI groups receiving different concentrations of acteoside. After 28 days of disease induction and treatment with acteoside, a BBB score test was used to evaluate locomotor activity. Then, by preparing spinal cord cell homogenates, the expression levels of MAP1LC3A, MAP-2, glial fibrillary acidic protein (GFAP), Nrf2, Keap-1, Caspase 3 (Casp3), Bax, Bcl-2, TNF-a, IL-1B, reactive oxygen species (ROS), and malondialdehyde (MDA) were measured. Improvement of locomotor activity in SCI rats receiving acteoside was observed two weeks after the beginning of the experiment and continued until the fourth week. Both MAP1LC3A and MAP-2 were significantly up-regulated in SCI rats treated with acteoside compared to untreated SCI rats, and GFAP levels were significantly decreased in these animals. Pro-apoptotic proteins Bax and Casp3 and anti-apoptotic protein Bcl-2 were down-regulated and up-regulated, respectively, in SCI rats receiving acteoside. In addition, a significant downregulation of iNOS, TNF-α, and IL-1β and a decrease in contents of both ROS and MDA as well as increases in Nrf2 and Keap-1 were seen in rats receiving acteoside. Furthermore, acteoside strongly interacted with MAP1LC3A, TNF-α, and Casp3 targets with binding affinities of -8.3 kcal/mol, -8.3 kcal/mol, and -8.5 kcal/mol, respectively, determined by molecular docking studies. In general, it can be concluded that acteoside has protective effects in SCI and can be considered as an adjuvant therapy in the treatment of this disease. However, more studies, especially clinical studies, are needed in this field.

Network pharmacological study and in vitro studies validation-Molecular dynamics simulation of Cistanche deserticola in promoting periodontitis and bone remodeling

OBJECTIVE

Periodontitis is a chronic infectious disease, characterized by loss of alveolar bone and supporting tissues. Cistanche deserticola(Cd), a local medicinal herb in Xinjiang, possesses favorable biological characteristics and potential applications. Our aim is to investigate the remodeling properties of Cd extract and elucidate the specific mechanisms underlying its therapeutic effects on periodontitis, by employing a combination of basic experimental and network pharmacology approaches.

METHODS

Firstly, UHPLC-QTOF-MS analysis was conducted on Cd extract to identify its main components, with several compounds were identified by standard. Subsequently, in vitro studies were performed using the Cd extract on MC3T3-E1 cells. Cell proliferation viability was assessed using CCK-8 and apoptosis assays, while ALP and ARS staining and quantitative experiments, qRT-PCR, and Western blot assays were employed to evaluate the osteogenic differentiation capability. Network pharmacology analysis was then carried out using the identified compounds to establish a database of Cd components and targets, along with a database of periodontitis. The intersection of these databases revealed the network relationship between Cd components-mapped genes-signaling pathways. KEGG/GO pathway analysis of the targets was performed to filter potential enriched pathways. PPI/CytoHubba protein interaction network analysis was utilized to identify hub genes. Molecular docking and molecular dynamics simulations were employed to analyze the docking and interaction between core gene and Cd components.

RESULTS

We detected 38 major components in the Cd extract, with Echinacoside, Acteoside, Tubuloside A, and Cistanoside A undergoing standard substance verification. In vitro studies indicated that the Cd, at concentrations below 100 μg/ mL, did not affect cell proliferation and inhibited apoptosis. Osteogenesis assays demonstrated that Cd at concentrations of 1 μg/ mL, 10 μg/ mL, and 100 μg/ mL significantly promoted the osteogenic differentiation ability of MC3T3-E1 cells. It also notably upregulated the mRNA and protein levels of Alp, Bmp2, Runx2, and Opn, and the optimal concentration was 10 μg/mL. Network pharmacology results revealed the network relationship between Cd's components, crossed targets and signaling pathways. Combined with KEGG/GO pathway analysis and PPI/CytoHubba protein interaction network analysis. The key pathway and hub genes of Cd regulating periodontitis are both related to hypoxia pathway and HIF-1α. Molecular docking results showed a strong binding affinity between Cd compounds and hub genes, and molecular dynamics simulation results indicated the stability of the complexes formed between HIF-1α and several Cd compounds.

CONCLUSION

Cistanche deserticola exhibits a notable capacity to promote bone regeneration, and its mechanism of action in regulating periodontitis is associated with the hypoxia signaling pathway. HIF-1α may serve as a potential core gene. Future research will focus on exploring the mechanism of Cd in intervene periodontitis and promoting bone remodeling in hypoxic environment.

The Function and Mechanism of Anti-Inflammatory Factor Metrnl Prevents the Progression of Inflammatory-Mediated Pathological Bone Osteolytic Diseases

Metrnl, recently identified as an adipokine, is a secreted protein notably expressed in white adipose tissue, barrier tissues, and activated macrophages. This adipokine plays a pivotal role in counteracting obesity-induced insulin resistance. It enhances adipose tissue functionality by promoting adipocyte differentiation, activating metabolic pathways, and exerting anti-inflammatory effects. Extensive research has identified Metrnl as a key player in modulating inflammatory responses and as an integral regulator of muscle regeneration. These findings position Metrnl as a promising biomarker and potential therapeutic target in treating inflammation-associated pathologies. Despite this, the specific anti-inflammatory mechanisms of Metrnl in immune-mediated osteolysis and arthritis remain elusive, warranting further investigation. In this review, we will briefly elaborate on the role of Metrnl in anti-inflammation function in inflammation-related osteolysis, arthritis, and pathological bone resorption, which could facilitate Metrnl's clinical application as a novel therapeutic strategy to prevent bone loss. While the pathogenesis of elbow stiffness remains elusive, current literature suggests that Metrnl likely exerts a pivotal role in its development.

Actoeside mitigated the renal proximal tubule cells damage triggered by high glucose through miR-766/VCAM1/NF-κB signalling pathway

CONTEXT

Diabetic nephropathy (DN) triggered by diabetes mellitus is one of the primary causes of end-stage renal failure worldwide.

OBJECTIVE

This study intends to explore the function and potential mechanism of actoeside on renal proximal tubule (HK-2) cells damage induced by high-glucose (HG).

METHODS

The DN model was established in HK-2 cells with 30 mM HG treatment. The viability, apoptosis and inflammation of HK-2 cells were analysed severally via CCK-8, flow cytomery and ELISA. The key factors related to NF-κB were detected by western blotting.

RESULTS

Actoeside attenuated the HG-induced HK-2 cells damage. The differentially expression of miR-766 and VCAM1 in DN patients was reversed by actoeside. Moreover, the increased phosphorylation levels of p65 NF-κB/IκBα induced by HG were attenuated by actoeside.

CONCLUSIONS

Actoeside promoted the growth and repressed the apoptosis and inflammation of HK-2 cells via miR-766/VCAM1/NF-κB signalling pathway, affording a promising idea for the treatment of DN.

IL-17 in osteoarthritis: A narrative review

Osteoarthritis (OA) is a painful joint disease that is common among the middle-aged and elderly populations, with an increasing prevalence. Therapeutic options for OA are limited, and the pathogenic mechanism of OA remains unclear. The roles of cytokines and signaling pathways in the development of OA is a current research hot spot. Interleukin (IL)-17 is a pleiotropic inflammatory cytokine produced mainly by T helper 17 cells that has established roles in host defense, tissue repair, lymphoid tissue metabolism, tumor progression, and pathological processes of immune diseases, and studies in recent years have identified an important role for IL-17 in the progression of OA. This narrative review focuses on the mechanisms by which IL-17 contributes to articular cartilage degeneration and synovial inflammation in OA and discusses how IL-17 and the IL-17 signaling pathway affect the pathological process of OA. Additionally, therapeutic targets that have been proposed in recent years based on IL-17 and its pathway in OA are summarized as well as recent advances in the study of IL-17 pathway inhibitors and the potential challenges of their use for OA treatment.

Beyond mechanical loading: The metabolic contribution of obesity in osteoarthritis unveils novel therapeutic targets

Osteoarthritis (OA) is a prevalent progressive disease that frequently coexists with obesity. For several decades, OA was thought to be the result of ageing and mechanical stress on cartilage. Researchers' perspective has been greatly transformed when cumulative findings emphasized the role of adipose tissue in the diseases. Nowadays, the metabolic effect of obesity on cartilage tissue has become an integral part of obesity research; hoping to discover a disease-modifying drug for OA. Recently, several adipokines have been reported to be associated with OA. Particularly, metrnl (meteorin-like) and retinol-binding protein 4 (RBP4) have been recognized as emerging adipokines that can mediate OA pathogenesis. Accordingly, in this review, we will summarize the latest findings concerned with the metabolic contribution of obesity in OA pathogenesis, with particular emphasis on dyslipidemia, insulin resistance and adipokines. Additionally, we will discuss the most recent adipokines that have been reported to play a role in this context. Careful consideration of these molecular mechanisms interrelated with obesity and OA will undoubtedly unveil new avenues for OA treatment.

Hederagenin Suppresses Inflammation and Cartilage Degradation to Ameliorate the Progression of Osteoarthritis: An In vivo and In vitro Study

Osteoarthritis (OA), a common degenerative joint disease, is characterized by the progressive degradation of articular cartilage and inflammation. Hederagenin (HE) is a pentacyclic triterpenoid saponin extracted from many herb plants. It has anti-inflammatory, anti-lipid peroxidative, anti-cancer, and neuroprotective activities. However, its effect on OA has not been investigated. Our study found that HE may be a potential anti-OA drug. In vitro, HE could suppress extracellular matrix (ECM) degradation via up-regulating aggrecan and Collagen II levels as well as downregulating MMPs and ADAMTS5 levels. It could also reduce proinflammatory and inflammatory cytokines or enzymes production, including TNF-α, IL-6, iNOS, COX-2, NO, and PGE₂. Besides, HE markedly reduced IL-1β-induced C28/I2 cell apoptosis and ROS accumulation. Mechanistically, HE exerted chondroprotective and anti-inflammatory effects by partly inhibiting JAK2/STAT3/MAPK signalling pathway and the crosstalk of the two pathways. Also, HE exhibited anti-apoptotic and anti-oxidative effect via targeting Keap1-Nrf2/HO-1/ROS/Bax/Bcl-2 axis. In vivo, HE significantly reduced monosodium iodoacetate (MIA) induced cartilage destruction of rats with a lower OARSI score and inflammatory cytokine levels, further demonstrating its protective effects in OA progression. These results suggest that HE is a potential compound for the development of drugs to treat OA.

Mechanisms by which kidney-tonifying Chinese herbs inhibit osteoclastogenesis: Emphasis on immune cells

The immune system plays a crucial role in regulating osteoclast formation and function and has significance for the occurrence and development of immune-mediated bone diseases. Kidney-tonifying Chinese herbs, based on the theory of traditional Chinese medicine (TCM) to unify the kidney and strengthen the bone, have been widely used in the prevention and treatment of bone diseases. The common botanical drugs are tonifying kidney-yang and nourishing kidney-yin herbs, which are divided into two parts: one is the compound prescription of TCM, and the other is the single preparation of TCM and its active ingredients. These botanical drugs regulate osteoclastogenesis directly and indirectly by immune cells, however, we have limited information on the differences between the two botanical drugs in osteoimmunology. In this review, the mechanism by which kidney-tonifying Chinese herbs inhibiting osteoclastogenesis was investigated, emphasizing the immune response. The differences in the mechanism of action between tonifying kidney-yang herbs and nourishing kidney-yin herbs were analysed, and the therapeutic value for immune-mediated bone diseases was evaluated.

Phytochemicals, Biological Activities, Molecular Mechanisms, and Future Prospects of Plantago asiatica L

Plantago asiatica L. has been used as a vegetable and nutritious food in Asia for thousands of years. According to recent phytochemical and pharmacological research, the active compositions of the plant contribute to various health benefits, such as antioxidant, anti-inflammatory, antibacterial, antiviral, and anticancer. This article reviews the 87 components of the plant and their structures, as well as their biological activities and molecular research progress, in detail. This review provides valuable reference material for further study, production, and application of P. asiatica, as well as its components in functional foods and therapeutic agents.

Perturbations in Neuroinflammatory Pathways Are Associated With a Worst Pain Profile in Oncology Patients Receiving Chemotherapy

Unrelieved pain occurs in 55% of cancer patients. Identification of molecular mechanisms for pain may provide insights into therapeutic targets. Purpose was to evaluate for perturbations in neuroinflammatory pathways between oncology patients with and without severe pain. Worst pain severity was rated using a 0 to 10 numeric rating scale six times over two cycles of chemotherapy. Latent profile analysis was used to identify subgroups of patients with distinct pain profiles. Pathway impact analyses were performed in two independent samples using gene expression data obtained from RNA sequencing (n = 192) and microarray (n = 197) technologies. Fisher's combined probability test was used to identify significantly perturbed pathways between None versus the Severe pain classes. In the RNA sequencing and microarray samples, 62.5% and 56.3% of patients were in the Severe pain class, respectively. Nine perturbed pathways were related to neuroinflammatory mechanisms (i.e., retrograde endocannabinoid signaling, gamma-aminobutyric acid synapse, glutamatergic synapse, Janus kinase-signal transducer and activator of transcription signaling, phagosome, complement and coagulation cascades, cytokine-cytokine receptor interaction, chemokine signaling, calcium signaling). First study to identify perturbations in neuroinflammatory pathways associated with severe pain in oncology outpatients. Findings suggest that complex neuroimmune interactions are involved in the maintenance of chronic pain conditions. Perspective: In this study that compared oncology patients with none versus severe pain, nine perturbed neuroinflammatory pathways were identified. Findings suggest that complex neuroimmune interactions are involved in the maintenance of persistent pain conditions.

Acteoside alleviates dextran sulphate sodium‑induced ulcerative colitis via regulation of the HO‑1/HMGB1 signaling pathway

Ulcerative colitis (UC) is a significant burden on human health, and the elucidation of the mechanism by which it develops has potential for the prevention and treatment of UC. It has been reported that acteoside (ACT) exhibits strong anti‑inflammatory activity. In the present study, it was hypothesized that ACT may exert a protective effect against UC. The effects of ACT on inflammation, oxidative stress and apoptosis were evaluated using dextran sulphate sodium (DSS)‑treated mice and DSS‑treated human colorectal adenocarcinoma Caco‑2 cells, which have an epithelial morphology. The results demonstrated that the ACT‑treated mice with DSS‑induced UC exhibited significantly reduced colon inflammation, as demonstrated by a reversal in body weight loss, colon shortening, disease activity index score, inflammation, oxidative stress and colonic barrier dysfunction. Further in vivo experiments demonstrated that ACT inhibited DSS‑induced apoptosis in colon tissues, as demonstrated by the results of the TUNEL assay and the altered protein expression levels of Bax, cleaved caspase‑3 and Bcl‑2. Furthermore, DSS significantly stimulated the protein expression levels of high mobility group box 1 protein (HMGB1), which serves a central role in the initiation and progression of UC, an effect which was markedly inhibited by ACT. Finally, DSS significantly decreased the protein expression levels of heme oxygenase‑1 (HO‑1) in colon tissues and the effect of ACT on GSH, apoptotic proteins and HMGB1 was markedly attenuated in the presence of the HO‑1 inhibitor tin protoporphyrin. In conclusion, ACT ameliorated colon inflammation through HMGB1 inhibition in a HO‑1‑dependent manner.

In vitro characterization of iridoid and phenylethanoid glycosides from Cistanche phelypaea for nutraceutical and pharmacological applications

"Desert hyacinths" are a remarkable group of parasitic plants belonging to genus Cistanche, including more than 20 accepted species typically occurring in deserts or coastal dunes parasitizing roots of shrubs. Several Cistanche species have long been a source of traditional herbal medicine or food, being C. deserticola and C. tubulosa the most used in China. This manuscript reports the isolation and identification of some phenylethanoid and iridoid glycosides, obtained from the hydroalcoholic extract of C. phelypaea collected in Spain. The present study aims to characterize the antioxidant activity of C. phelypaea metabolites in the light of their application in nutraceutical and cosmeceutical industries and the effect of acetoside, the most abundant metabolite in C. phelypaea extract, on human keratinocyte and pluripotent stem cell proliferation and differentiation. Our study demonstrated that acetoside, besides its strong antioxidant potential, can preserve the proliferative potential of human basal keratinocytes and the stemness of mesenchymal progenitors necessary for tissue morphogenesis and renewal. Therefore, acetoside can be of practical relevance for the clinical application of human stem cell cultures in tissue engineering and regenerative medicine.

Acteoside attenuates acute lung injury following administration of cobra venom factor to mice

Background

Acteoside, a water-soluble active constituent of diverse valuable medicinal vegetation, has shown strong anti-inflammatory property. However, studies on the anti-inflammatory property of acteoside in complement-induced acute lung injury (ALI) are limited. Therefore, this study aims to evaluate the anti-inflammatory activity of acteoside in cobra venom factor (CVF)-stimulated human microvascular endothelial cells (HMEC) and in ALI mice model.

Methods

In this study, we investigated the effects of acteoside (20, 10, and 5 μg/mL) in vitro in CVF induced HMECs and the activity of acteoside (100, 50, and 20 mg/kg/day bodyweight) in vivo in CVF induced ALI mice. Each eight male mice were orally administered acteoside or the positive drug PDTC (100 mg/kg/day) for 7 days before CVF (35 μg/kg) injection. After injection for 1 h, the pharmacological effects of acteoside were investigated by spectrophotometry, pathological examination, enzyme-linked immunosorbent assay, and immunohistochemistry.

Results

In vitro, acteoside (20, 10, and 5 μg/mL) reduced the protein expression of adhesion molecules and pro-inflammatory cytokines and transcriptional activity of NF-κB (P < 0.01). In vivo studies showed that acteoside dose-dependently alleviated lung histopathologic lesion, inhibited the production of the protein content of BALF, leukocyte cell number, lung MPO activity, and expression levels of IL-6, TNF-α, and ICAM-1, and suppressed the C5b-9 deposition and NF-κB activation in CVF-induced acute lung inflammation in mice (P < 0.05, 0.01).

Conclusion

This study demonstrates that acteoside exerts strong anti-inflammatory activities in the CVF-induced acute lung inflammation model and suggests that acteoside is a potential therapeutic agent for complement-related inflammatory diseases.

The pharmacokinetic property and pharmacological activity of acteoside: A review

Acteoside (AC), a phenylpropanoid glycoside isolated from many dicotyledonous plants, has been demonstrated various pharmacological activities, including anti-oxidation, anti-inflammation, anti-cancer, neuroprotection, cardiovascular protection, anti-diabetes, bone and cartilage protection, hepatoprotection, and anti-microorganism. However, AC has a poor bioavailability, which can be potentially improved by different strategies. The health-promoting characteristics of AC can be attributed to its mediation in many signaling pathways, such as MAPK, NF-κB, PI3K/AKT, TGFβ/Smad, and AMPK/mTOR. Interestingly, docking simulation study indicates that AC can be an effective candidate to inhibit the activity of SARS-CoV2 main protease and protect against COVID-19. Many clinical trials for AC have been investigated, and it shows great potentials in drug development.

Pedicularis resupinata Extract Prevents Depressive-like Behavior in Repeated Corticosterone-Induced Depression in Mice: A Preliminary Study

Excessive corticosterone (CORT), resulting from a dysregulated hypothalamic–pituitary–adrenal (HPA) axis, is associated with cognitive impairment and behavioral changes, including depression. In Korean oriental medicine, Pedicularis resupinata is used for the treatment of inflammatory diseases such as rheumatoid arthritis. However, the antidepressant properties of P. resupinata have not been well characterized. Here, the antidepressant-like effects of P. resupinata extract (PRE) were evaluated in terms of CORT-induced depression using in vivo models. HPLC confirmed that acteoside, a phenylethanoid glycoside, was the main compound from PRE. Male ICR mice (8 weeks old) were injected with CORT (40 mg/kg, i.p.) and orally administered PRE daily (30, 100, and 300 mg/kg) for 21 consecutive days. Depressive-like behaviors were evaluated using the open-field test, sucrose preference test, passive avoidance test, tail suspension test, and forced swim test. Treatment with a high dose of PRE significantly alleviated CORT-induced, depressive-like behaviors in mice. Additionally, repeated CORT injection markedly reduced brain-derived neurotrophic factor levels, whereas total glucocorticoid receptor (GR) and GR phosphorylation at serine 211 were significantly increased in the mice hippocampus but improved by PRE treatment. Thus, our findings suggest that PRE has potential antidepressant-like effects in CORT-induced, depressive-like behavior in mice.

Effects of Acanthus ebracteatus Vahl. extract and verbascoside on human dermal papilla and murine macrophage

Androgenic alopecia is a common type of hair loss, usually caused by testosterone metabolism generating dihydrotestosterone and hair follicular micro-inflammation. These processes induce dermal papilla cells to undergo apoptosis. Currently approved effective medications for alopecia are Finasteride, an oral 5α-reductase inhibitor, Minoxidil, a topical hair growth promoter, and Diclofenac, an anti-inflammatory agent, all of which, however, have several adverse side effects. In our study, we showed the bioactivity of Acanthus ebracteatus Vahl. (AE) extract performed by 95% ethanol, and verbascoside (VB), a biomarker of AE extract. Both AE extract and VB were studied for their effects on dermal papilla cell viability and the cell cycle by using MTT assay and flow cytometry. The effect of an anti-inflammatory activity of AE extract and VB on IL-1β, NO, and TNF-α, released from LPS induced RAW 264.7 cells, and IL-1α and IL-6 released from irradiated dermal papilla cells were detected using ELISA technique. The preventive effect on dermal papilla cell apoptosis induced by testosterone was determined by MTT assay. In controlled in vitro assays it was found that AE extract and VB at various concentrations induced dermal papilla cell proliferation which was indicated by an increase in the number of cells in the S and G2/M phases of the cell cycle. AE extract at 250 µg/mL concentration or VB at 62.50 µg/mL concentration prevented cell apoptosis induced by testosterone at a statistically significant level. In addition, both AE extract and VB greatly inhibited the release of pro-inflammatory cytokines from RAW 264.7 and dermal papilla cells. The release of IL-1β, TNF-α, and NO from RAW 264.7 cells, as well as IL-1α and IL-6 from dermal papilla cells, was also diminished by AE extract 250 µg/mL and VB 125 µg/mL. Our results indicate that AE extract and VB are promising ingredients for anti-hair loss applications. However, further clinical study is necessary to evaluate the effectiveness of AE extract and VB as treatment for actual hair loss.

The potential roles of JAK/STAT signaling in the progression of osteoarthritis

Osteoarthritis (OA) is an age-related chronic progressive degenerative disease that induces persistent pain and disabilities. The development of OA is a complex process, and the risk factors are various, including aging, genetics, trauma and altered biomechanics. Inflammation and immunity play an important role in the pathogenesis of OA. JAK/STAT pathway is one of the most prominent intracellular signaling pathways, regulating cell proliferation, differentiation, and apoptosis. Inflammatory factors can act as the initiators of JAK/STAT pathway, which is implicated in the pathophysiological activity of chondrocyte. In this article, we provide a review on the importance of JAK/STAT pathway in the pathological development of OA. Potentially, JAK/STAT pathway becomes a therapeutic target for managing OA.

Silencing of TLR7 protects against lipopolysaccharide-induced chondrocyte apoptosis and injury by blocking the p21-mediated JAK2/STAT3 pathway

Involvement of toll-like receptor 7 (TLR7) in the immune response has been reported in diverse inflammatory diseases. However, the role of TLR7 in the pathogenesis of osteoarthritis (OA) is poorly understood. In this study, we sought to investigate the contribution of TLR7 in regulating chondrocyte apoptosis, inflammation, and degradation of the extracellula matrix (ECM), and its underlying mechanisms. We found that TLR7 expression was increased in cartilage tissues of OA patients and in lipopolysaccharide (LPS)-induced chondrocytes. Silencing of TLR7 alleviated LPS-induced chondrocyte apoptosis, inflammation, and ECM degradation. Mechanistically, TLR7 silencing inhibited the JAK2/STAT3 signaling pathway by inducing p21 expression. Moreover, p21 knockdown and colivein (an activator of JAK2/STAT3 signaling) partially rescued the suppressive role of TLR7 silencing on chondrocyte apoptosis, the inflammatory response, and ECM underproduction. Taken together, our data revealed that knockdown of TLR7 attenuated chondrocyte apoptosis and injury by blocking the p21-mediated JAK2/STAT3 pathway, suggesting that TLR7 may be a therapeutic target in OA.

Applications of bioactive compounds extracted from olive industry wastes: A review

The wastes generated during the olive oil extraction process, even if presenting a negative impact for the environment, contain several bioactive compounds that have considerable health benefits. After suitable extraction and purification, these compounds can be used as food antioxidants or as active ingredients in nutraceutical and cosmetic products due to their interesting technological and pharmaceutical properties. The aim of this review, after presenting general applications of the different types of wastes generated from this industry, is to focus on the olive pomace produced by the two-phase system and to explore the challenging applications of the main individual compounds present in this waste. Hydroxytyrosol, tyrosol, oleuropein, oleuropein aglycone, and verbascoside are the most abundant bioactive compounds present in olive pomace. Besides their antioxidant activity, these compounds also demonstrated other biological properties such as antimicrobial, anticancer, or anti-inflammatory, thus being used in formulations to produce pharmaceutical and cosmetic products or in the fortification of food. Nevertheless, it is mandatory to involve both industries and researchers to create strategies to valorize these byproducts while maintaining environmental sustainability.

Injectable hydrogel mediated delivery of gene-engineered adipose-derived stem cells for enhanced osteoarthritis treatment

Osteoarthritis (OA), a chronic and degenerative joint disease, remains a challenge in treatment due to the lack of disease-modifying therapies. As a promising therapeutic agent, adipose-derived stem cells (ADSCs) have an effective anti-inflammatory and chondroprotective paracrine effect that can be enhanced by genetic modification. Unfortunately, direct cell delivery without matrix support often results in poor viability of therapeutic cells. Herein, a hydrogel implant approach that enabled intra-articular delivery of gene-engineered ADSCs was developed for improved therapeutic outcomes in a surgically induced rat OA model. An injectable extracellular matrix (ECM)-mimicking hydrogel was prepared as the carrier for cell delivery, providing a favorable microenvironment for ADSC spreading and proliferation. The ECM-mimicking hydrogel could reduce cell death during and post injection. Additionally, ADSCs were genetically modified to overexpress transforming growth factor-β1 (TGF-β1), one of the paracrine factors that exert an anti-inflammatory and pro-anabolic effect. The gene-engineered ADSCs overexpressing TGF-β1 (T-ADSCs) had an enhanced paracrine effect on OA-like chondrocytes, which effectively decreased the expression of tumor necrosis factor-alpha and increased the expression of collagen II and aggrecan. In a surgically induced rat OA model, intra-articular injection of the T-ADSC-loaded hydrogel markedly reduced cartilage degeneration, joint inflammation, and the loss of the subchondral bone. Taken together, this study provides a potential biomaterial strategy for enhanced OA treatment by delivering the gene-engineered ADSCs within an ECM-mimicking hydrogel.

Baicalein Delays H2O2-Induced Astrocytic Senescence through Inhibition of Senescence-Associated Secretory Phenotype (SASP), Suppression of JAK2/STAT1/NF-κB Pathway, and Regulation of Leucine Metabolism

Baicalein is an active ingredient extracted from the dried roots of the Scutellaria baicalensis Georgi. It has been demonstrated to improve memory impairment in multiple animal models; however, the underlying mechanisms remain ambiguous. The accumulation of senescent astrocytes and senescence-associated secretory phenotype (SASP) secreted by senescent astrocytes has been deemed as potential contributors to neurodegenerative diseases. Therefore, this study explored the protective effects of baicalein against astrocyte senescence and investigated the molecular mechanisms and metabolic mechanisms of baicalein against astrocyte senescence. Our results demonstrated that treatment with baicalein protects T98G cells from H₂O₂-induced damage, delays cell senescence, inhibits the secretion of SASP (IL-6, IL-8, TNF-α, CXCL1, and MMP-1), and inhibits SASP-related pathways NF-κB and JAK2/STAT1. ¹H NMR metabolomics analysis and correlation analysis revealed that leucine was significantly correlated with SASP factors. Further study demonstrated that supplement with leucine could restrain SASP secretion, and baicalein could significantly increase leucine level through down-regulation of BCAT1 and up-regulation of SLC7A5 expression. The above results revealed that baicalein exerted protective and antisenescence effects in H₂O₂-induced T98G cells possibly through inhibition of SASP, suppression of JAK2/STAT1/NF-κB pathway, and regulation of leucine metabolism. Consistent results were obtained in primary astrocytes of newborn SD rats, which suggests that baicalein significantly increases viabilities, delays senescence, inhibits IL-6 secretion, and increases leucine level in H₂O₂-induced primary astrocytes.

Inhibitory activity of acteoside in melanoma via regulation of the ERβ-Ras/Raf1-STAT3 pathway

BACKGROUND

Melanoma is an aggressive cancer with a rapidly increasing incidence rate worldwide. Acteoside has been shown to have antitumor effects in multiple human cancers; however, the underlying function and mechanisms of acteoside in melanoma remain unclear.

PURPOSE

This study explored the inhibitory effect of acteoside on melanoma and the possible mechanisms.

METHODS

Acteoside (15 mg/kg, 30 mg/kg) was administered to mice daily for 21 days. ICI182,780 (0.5 mg/kg) was intraperitoneally injected 30 min before acteoside administration three times a week to evaluate whether the effects elicited by acteoside were mediated via the estrogen receptor. Tumor growth and metabolism, cardiac function, ROS and apoptosis levels in the spleen, serum inflammatory factors, and immune cells in the spleen were monitored. STAT3, p-STAT3, CD31, and survivin levels in tumor tissues were measured via immunofluorescence. Ras, Raf1, STAT3, p-STAT3, Bcl-2, Bax, cleaved caspase-3, and cleaved caspase-9 levels in tumor tissues were determined via Western Blotting.

RESULTS

The results showed that acteoside inhibited melanoma growth, alleviated inflammation levels in mice, attenuated ROS and apoptosis levels in the spleen, downregulated the levels of CD31, survivin, Ras, Raf1, p-STAT3, and Bcl-2, and upregulated the levels of ERβ, Bax, cleaved caspase-3, and cleaved caspase-9. Moreover, the effect of acteoside was blocked by ICI182,780.

CONCLUSION

Acteoside may promote the apoptosis of tumor cells by regulating the ERβ-Ras/Raf1-STAT3 signaling axis, thus inhibiting the occurrence and development of melanoma.

Knockdown of hsa_circ_0134111 alleviates the symptom of osteoarthritis via sponging microRNA-224-5p

The relevance of circular RNAs (circRNAs) has been indicated in the progression of various diseases. Nevertheless, the precise function of circRNAs in osteoarthritis (OA) remains to be established. Therefore, we aimed to investigate changes in the expression of a specific circRNA, hsa_circ_0134111 (circ_PDE1C) and predict its functions in OA. A rat model of OA was constructed to detect circ_PDE1C expression in knee joint tissues. Subsequently, CHON-001 chondrocytes were treated with IL-1β to mimic OA in vitro. circ_PDE1C was significantly overexpressed in knee cartilage tissues from OA patients relative to amputation patients. Knockdown of circ_PDE1C inhibited extracellular matrix (ECM) degradation and chondrocyte apoptosis. Furthermore, circ_PDE1C could target miR-224-5p, and miR-224-5p expressed poorly in knee cartilage tissues from OA patients. Overexpression of miR-224-5p inhibited ECM degradation and apoptosis in chondrocytes. miR-224-5p also targeted CCL2, which activated the JAK2/STAT signaling pathway, thereby promoting cartilage degradation and exacerbating the symptoms of OA patients. In conclusion, our findings underscore a novel role of circ_PDE1C in OA pathogenesis and suggest that targeting circ_PDE1C/miR-224-5p/CCL2 axis might provide an attractive approach for OA therapy.

Edible and Herbal Plants for the Prevention and Management of COVID-19

Background: The outbreak of the pandemic coronavirus disease 2019 (COVID-19) has now become a global pandemic spreading throughout the world. Unfortunately, due to the high infectiousness of the novel β-coronavirus, it is very likely to become an ordinary epidemic. The development of dietary supplements and functional foods might provide a strategy for the prevention and management of COVID-19. Scope and Approach: A great diversity of potential edible and medicinal plants and/or natural compounds showed potential benefits in managing SARS, which may also combat COVID-19. Moreover, many plants and compounds have currently been proposed to be protective against COVID-19. This information is based on data-driven approaches and computational chemical biology techniques. In this study, we review promising candidates of edible and medicinal plants for the prevention and management of COVID-19. We primarily focus on analyzing their underlying mechanisms. We aim to identify dietary supplements and functional foods that assist in managing this epidemic. Key findings and Conclusion: We infer that acetoside, glyasperin, isorhamnetin, and several flavonoid compounds may prevent and/or be effective in managing COVID-19 by targeting the viral infection, reducing the host cytokine storm, regulating the immune response, and providing organ protection. These bioactive dietary components (used either alone or in combination) might assist in the development of dietary supplements or functional foods for managing COVID-19.

Acteoside Counteracts Interleukin-1β-Induced Catabolic Processes through the Modulation of Mitogen-Activated Protein Kinases and the NFκB Cellular Signaling Pathway

Osteoarthritis (OA) is the most common degenerative joint disease with chronic joint pain caused by progressive degeneration of articular cartilage at synovial joints. Acteoside, a caffeoylphenylethanoid glycoside, has various biological activities such as antimicrobial, anti-inflammatory, anticancer, antioxidative, cytoprotective, and neuroprotective effect. Further, oral administration of acteoside at high dosage does not cause genotoxicity. Therefore, the aim of present study is to verify the anticatabolic effects of acteoside against osteoarthritis and its anticatabolic signaling pathway. Acteoside did not decrease the viabilities of mouse fibroblast L929 cells used as normal cells and primary rat chondrocytes. Acteoside counteracted the IL-1β-induced proteoglycan loss in the chondrocytes and articular cartilage through suppressing the expression and activation of cartilage-degrading enzyme such as matrix metalloproteinase- (MMP-) 13, MMP-1, and MMP-3. Furthermore, acteoside suppressed the expression of inflammatory mediators such as inducible nitric oxide synthase, cyclooxygenase-2, nitric oxide, and prostaglandin E2 in the primary rat chondrocytes treated with IL-1β. Subsequently, the expression of proinflammatory cytokines was decreased by acteoside in the primary rat chondrocytes treated with IL-1β. Moreover, acteoside suppressed not only the phosphorylation of mitogen-activated protein kinases in primary rat chondrocytes treated with IL-1β but also the translocation of NFκB from the cytosol to the nucleus through suppression of its phosphorylation. Oral administration of 5 and 10 mg/kg acteoside attenuated the progressive degeneration of articular cartilage in the osteoarthritic mouse model generated by destabilization of the medial meniscus. Our findings indicate that acteoside is a promising potential anticatabolic agent or supplement to attenuate or prevent progressive degeneration of articular cartilage.

From Pathogenesis to Therapy in Knee Osteoarthritis: Bench-to-Bedside

Osteoarthritis (OA) is currently the most widespread musculoskeletal condition and primarily affects weight-bearing joints such as the knees and hips. Importantly, knee OA remains a multifactorial whole-joint disease, the appearance and progression of which involves the alteration of articular cartilage as well as the synovium, subchondral bone, ligaments, and muscles through intricate pathomechanisms. Whereas it was initially depicted as a predominantly aging-related and mechanically driven condition given its clear association with old age, high body mass index (BMI), and joint malalignment, more recent research identified and described a plethora of further factors contributing to knee OA pathogenesis. However, the pathogenic intricacies between the molecular pathways involved in OA prompted the study of certain drugs for more than one therapeutic target (amelioration of cartilage and bone changes, and synovial inflammation). Most clinical studies regarding knee OA focus mainly on improvement in pain and joint function and thus do not provide sufficient evidence on the possible disease-modifying properties of the tested drugs. Currently, there is an unmet need for further research regarding OA pathogenesis as well as the introduction and exhaustive testing of potential disease-modifying pharmacotherapies in order to structure an effective treatment plan for these patients.

FOXM1 activates JAK1/STAT3 pathway in human osteoarthritis cartilage cell inflammatory reaction

Osteoarthritis (OA), the most prevalent form of arthritis disease, is characterized by destruction of articular cartilage, osteophyte development, and sclerosis of subchondral bone. Transcription factors Janus kinase 1/signal transducer and activator of transcription 3 (JAK1/STAT3) and Forkhead box M1 (FOXM1) are key mediators of this inflammatory reaction. In this study, we investigated the interaction between JAK1/STAT3 and FOXM1 in OA. Inflammation is related to the cartilage damage, and lipopolysaccharides (LPS) are a major pro-inflammatory inducer, so LPS was utilized to stimulate chondrocytes and establish a cell-based OA model. We found LPS treatment caused a generation of inflammatory cell factors (IL-1β, IL-6, and TNF-α), and upregulation of inducible nitric oxide synthases (iNOS), cyclooxygenase-2 (COX-2), nitric oxide (NO), prostaglandin E2 (PGE2) and other inflammatory mediators. Cell viability of chondrocytes was impaired with LPS stimulation, along with an upregulation of JAK1 expression, and phosphorylation and nuclear accumulation of STAT3. The administration of STAT3 inhibitor WP1066, which abated activation and nuclear location of STAT3, depleted the effect of LPS on inflammation and cell death. Co-immunoprecipitation showed that STAT3 was able to bind to FOXM1, and deactivation of STAT3 resulted in the downregulation of FOXM1. Moreover, FOXM1 silencing inhibited the generation of inflammatory cytokines induced by LPS, and the attenuation of cell survival. These findings indicated that the interaction between JAK1/STAT3 and FOXM1 may play a key role in OA pathogenic studies, and suggest the JAK1/STAT3 pathway may be a potential target for OA therapy.

Parathyroid hormone (1-34) ameliorates cartilage degeneration and subchondral bone deterioration in collagenase-induced osteoarthritis model in mice

Aims

Parathyroid hormone (PTH) (1-34) exhibits potential in preventing degeneration in both cartilage and subchondral bone in osteoarthritis (OA) development. We assessed the effects of PTH (1-34) at different concentrations on bone and cartilage metabolism in a collagenase-induced mouse model of OA and examined whether PTH (1-34) affects the JAK2/STAT3 signalling pathway in this process.

Methods

Collagenase-induced OA was established in C57Bl/6 mice. Therapy with PTH (1-34) (10 μg/kg/day or 40 μg/kg/day) was initiated immediately after surgery and continued for six weeks. Cartilage pathology was evaluated by gross visual, histology, and immunohistochemical assessments. Cell apoptosis was analyzed by TUNEL staining. Microcomputed tomography (micro-CT) was used to evaluate the bone mass and the microarchitecture in subchondral bone.

Results

Enhanced matrix catabolism, increased apoptosis of chondrocytes in cartilage, and overexpressed JAK2/STAT3 and p-JAK2/p-STAT3 were observed in cartilage in this model. All of these changes were prevented by PTH (1-34) treatment, with no significant difference between the low-dose and high-dose groups. Micro-CT analysis indicated that bone mineral density (BMD), bone volume/trabecular volume (BV/TV), and trabecular thickness (Tb.Th) levels were significantly lower in the OA group than those in the Sham, PTH 10 μg, and PTH 40 μg groups, but these parameters were significantly higher in the PTH 40 μg group than in the PTH 10 μg group.

Conclusion

Intermittent administration of PTH (1-34) exhibits protective effects on both cartilage and subchondral bone in a dose-dependent manner on the latter in a collagenase-induced OA mouse model, which may be involved in regulating the JAK2/STAT3 signalling pathway.

Cite this article: Bone Joint Res 2020;9(10):675–688.

Isolation of bioactive components with soluble epoxide hydrolase inhibitory activity from Stachys sieboldii MiQ. by ultrasonic-assisted extraction optimized using response surface methodology

Stachys sieboldii MiQ (SSM) is an important food and medicinal herb in Korea, used to improve memory of patients with senile dementia and cardiovascular diseases. However, little information on bioactive components from SSM or standardized extraction methods for these components is available. This study isolated and purified major components from SSM for the first time, and assessed their ability to inhibit soluble epoxide hydrolase (sEH). The results showed that acteoside is the most potent inhibitor of sEH, with an IC₅₀ of 33.5 ± 0.5 μM. Additional active components, including harpagide, tryptophan, and 8-acetate-harpagide, along with acteoside, were tentatively identified using high-performance liquid chromatography photodiode array tandem mass spectrometry (HPLC-PDA-MS/MS) and quantified using an ultraviolet detector at 210 nm. Further, an ultrasonic-assisted extraction technique for extraction of four bioactive compounds in SSM was developed and optimized using response surface methodology (RSM). The optimal extraction conditions were: extraction time, 30.46 minutes; extraction temperature, 67.95 °C, and methanol concentration 53.85%. The prediction model of RSM was validated with laboratory experiments. The similarity between predicted and actual values was 97.84%. The extraction method is thus a rapid, environment-friendly, energy-saving method can be applied to extract bioactive components from SSM in large quantities.

The emerging role of lncRNAs in chondrocytes from osteoarthritis patients

Long non-coding RNAs (lncRNAs) play important roles in many physiological and pathological processes, including osteoarthritis (OA). Recent studies have demonstrated that lncRNAs are involved in the pathogenesis of OA by affecting various essential cellular features of chondrocytes, such as proliferation, apoptosis, inflammation, and degradation of the extracellular matrix (ECM). However, there are only a limited number of studies in this area, indicating that the role of lncRNAs in OA may have been overlooked. The aim of this literature review is to summarize the versatile roles and molecular mechanisms of lncRNAs in chondrocytes involved in OA. At the end of this article, the function of the lncRNA HOX transcript antisense RNA (HOTAIR) in chondrocytes in OA is highlighted. Because lncRNAs affect proliferation, apoptosis, inflammatory responses, and ECM degradation by chondrocytes in OA, they may serve as potential biomarkers or therapeutic targets for the diagnosis or treatment of OA. The specific role and related mechanisms of lncRNAs in OA warrants further investigation.

Inhibition of GPR17 with pranlukast protects against TNF-α-induced loss of type II collagen in ATDC5 cells

Osteoarthritis (OA) is a common joint disease affecting millions of elderly people worldwide. However, the mechanism of OA is complicated and remains poorly understood. Thus, a safe and effective therapeutic strategy has yet to be developed. G protein-coupled receptor 17 (GPR17) is an orphan receptor that is widely distributed in the central nervous system (CNS). GPR17 has become a target for the treatment of inflammation in brain diseases. In this study, we demonstrate that GPR17 is expressed in ATDC5 cells and is increased in response to TNF-α exposure. We also found that antagonism of GPR17 with pranlukast significantly inhibited oxidative stress by downregulating the intracellular level of reactive oxygen species (ROS) and increasing the activity of super oxide dismutase (SOD) against TNF-α. Interestingly, treatment with pranlukast prevented TNF-α-induced reduction of type II collagen. Additionally, knockdown of GPR17 with siRNA ameliorated TNF-α-induced loss of type II collagen, suggesting the importance of the role of GPR17 in mediating the impairment of type II collagen. Blockage of GPR17 with pranlukast suppressed the expression of matrix metalloproteinases 3 (MMP-3) and matrix metalloproteinases 13 (MMP-13), which contribute to the degradation of type II collagen. Pranlukast also prevented the activation of the JAK2/STAT1/IRF-1 signaling pathway, thereby suppressing the expression of pro-inflammatory cytokines and enzymes. Furthermore, pranlukast rescued TNF-α-induced reduced SOX-9 expression. Together, our data indicate that GPR17 might be a potential target for the treatment of OA.

Protective effect of Ganoderic acid A on adjuvant-induced arthritis

The purpose of the experiment was to explore the effect of Ganoderic acid A (GAA) on adjuvant-induced arthritis in rats. In this study, the rat model of collagen-induced rheumatoid arthritis (CIA) was established with type II collagen plus Freund's complete adjuvant. Arthritis index, joint pathology, toe swelling, hemorheology, synovial cell apoptosis, related cytokines and JAK3/STAT3 and nuclear factor-κB (NF-κB) signaling pathway were measured in rats. We found that GAA can significantly inhibit the arthritis index, improve joint pathology, reduce toe swelling, improve blood rheology, improve synovial cell apoptosis, and restore related cytokine negative regulation JAK3/STAT3 and NF-κB signaling pathways. In conclusion, GAA has an obvious therapeutic effect on joint inflammation of toes in CIA model rats, which may be due to the regulation of JAK3/STAT3 and NF-κB signaling pathway.

Mitochondrial dependent pathway is involved in the protective effects of carboxymethylated chitosan on nitric oxide-induced apoptosis in chondrocytes

Background

Chondrocyte apoptosis activated by the mitochondrial dependent pathway serves a crucial role in cartilage degeneration of osteoarthritis (OA). In the present study, the protective effects of CMCS against sodium nitroprusside (SNP)-induced chondrocyte apoptosis were evaluated and the underlying molecular mechanisms were elucidated.

Methods

Chondrocytes were isolated from articular cartilage of SD rats and identified by type II collagen immunohistochemistry. The chondrocytes stimulated with or without SNP to induce apoptosis, were treated by CMCS for various concentrations. The cell viability were determined by MTT and LDH assays. Cell apoptotic ratio was determined by Annexin V-FITC/PI staining. Mitochondrial membrane potential (ΔΨm) was detected by using Rhodamine123 (Rho123) staining. To understand the mechanism, the mRNA expression levels of Bcl-2, Bax, cytochrome c (Cyt c) and cleaved caspase-3 were detected by real-time PCR and western blot analysis, respectively.

Results

It was shown using the MTT and LDH assays that CMCS protected the viability of chondrocyte against SNP damage. Annexin V-FITC/PI and Rho123 staining showed that CMCS not only inhibited the cell apoptosis but also restored the reduction of the ΔΨm in chondrocytes. In SNP-induced chondrocytes, CMCS down-regulated the expression of Bax, Cyt c and cleaved caspase-3 but upregulated the expression of Bcl-2, as shown by real-time PCR and western blot.

Conclusions

Taken together, these results indicated that CMCS has the protective effect on chondrocytes against SNP-induced apoptosis, at least partly, via inhibiting the mitochondrial dependent apoptotic pathway. Thus, CMCS may be potentially used as a biological agent for prevention and treatment of OA.