Harnessing ferroptosis for enhanced sarcoma treatment: mechanisms, progress and prospects.

Sarcoma is a malignant tumor that originates from mesenchymal tissue. The common treatment for sarcoma is surgery supplemented with radiotherapy and chemotherapy. However, patients have a 5-year survival rate of only approximately 60%, and sarcoma cells are highly resistant to chemotherapy. Ferroptosis is an iron-dependent nonapoptotic type of regulated programmed cell death that is closely related to the pathophysiological processes underlying tumorigenesis, neurological diseases and other conditions. Moreover, ferroptosis is mediated via multiple regulatory pathways that may be targets for disease therapy. Recent studies have shown that the induction of ferroptosis is an effective way to kill sarcoma cells and reduce their resistance to chemotherapeutic drugs. Moreover, ferroptosis-related genes are related to the immune system, and their expression can be used to predict sarcoma prognosis. In this review, we describe the molecular mechanism underlying ferroptosis in detail, systematically summarize recent research progress with respect to ferroptosis application as a sarcoma treatment in various contexts, and point out gaps in the theoretical research on ferroptosis, challenges to its clinical application, potential resolutions of these challenges to promote ferroptosis as an efficient, reliable and novel method of clinical sarcoma treatment.

MiR-181a-5p promotes osteogenesis by targeting BMP3.

High-throughput microRNA (miRNA) sequencing of osteoporosis was analyzed from the Gene Expression Omnibus (GEO) database to investigate specific microRNAs that control osteogenesis. MiR-181a-5p was differentially expressed among healthy subjects and those with osteoporosis. Inhibitors and mimics were transfected into cells to modulate miR-181a-5p levels to examine the role in MC3T3-E1 functions. Alkaline phosphatase (ALP) staining and Alizarin Red S (ARS) staining were used for morphological detection, and proteins of ALP and Runt-related transcription factor 2 (RUNX2), as osteogenesis markers, were detected. During the osteogenic differentiation of MC3T3-E1, the transcription level of miR-181a-5p was significantly increased. The inhibition of miR-181a-5p suppressed MC3T3-E1 osteogenic differentiation, whereas its overexpression functioned oppositely. Consistently, the miR-181a-5p antagomir aggravated osteoporosis in old mice. Additionally, we predicted potential target genes via TargetScan and miRDB and identified bone morphogenetic protein 3 (BMP3) as the target gene. Moreover, the reduced expression of miR-181a-5p was validated in our hospitalized osteoporotic patients. These findings have substantial implications for the strategies targeting miR-181a-5p to prevent osteoporosis and potential related fractures.

Cimifugin Suppresses NF-κB Signaling to Prevent Osteoclastogenesis and Periprosthetic Osteolysis.

Background: Aseptic loosening of prosthesis (ALP) is one of the most common long-term complications of knee and hip arthroplasty. Wear particle-induced osteoclastogenesis and subsequent periprosthetic osteolysis account for the morbidity of ALP. Here, we investigate the potential of cimifugin (CIM), a natural extract from Cimicifuga racemosa and Saposhnikovia divaricata, as a bone-protective drug in the treatment of ALP. Method: First, we performed cell viability and osteoclast formation assays to assess the effect of noncytotoxic CIM on osteoclast differentiation in vitro. Bone slice resorption and F-actin ring immunofluorescence assays were adopted to assess the effects of CIM on bone-resorption function. Then, quantitative real-time polymerase chain reaction (qRT-PCR) analysis was performed to further assess the repressive effects of CIM on osteoclastogenesis at the gene expression level. To elucidate the mechanisms underlying the above findings, Western blot and luciferase reporter gene assays were used to assess the regulatory effects of CIM on the NF-κB and MAPK signaling pathways. Moreover, a Ti particle-induced murine calvarial osteolysis model and subsequent histomorphometric analysis via micro-CT and immunohistochemical staining were used to elucidate the effect of CIM on periprosthetic osteolysis in vivo. Result: CIM dose-dependently inhibited both bone marrow-derived macrophage (BMM)- and RAW264.7 cell-derived osteoclastogenesis and bone resorption pit formation in vitro, which was further supported by the reduced expression of F-actin and osteoclast-specific genes. According to the Western blot analysis, inhibition of IκBα phosphorylation in the NF-κB signaling pathway, not the phosphorylation of MAPKs, was responsible for the suppressive effect of CIM on osteoclastogenesis. Animal experiments demonstrated that CIM alleviated Ti particle-induced bone erosion and osteoclast accumulation in murine calvaria. Conclusion: The current study suggested for the first time that CIM can inhibit RANKL-induced osetoclastogenesis by suppressing the NF-κB signaling pathway in vitro and prevent periprosthetic osteolysis in vivo. These findings suggest the potential of CIM as a therapeutic in ALP.

Microplastics on beaches and mangrove sediments along the coast of South China.

Accumulation of microplastics (MPs) data on a global scale is key to supporting plastic waste management for protecting ecosystems. To respond this call, a sampling campaign was conducted in the summer and winter seasons of 2018 to collect beach and mangrove sediment samples from 32 sites along the coastline of South China. The MPs concentrations in the intertidal zone along the coast of South China were comparable to those in other regions around the world. Polystyrene foams and fibers were the most abundant debris in the 0.2-5 mm and 0.02-2 mm MPs, respectively. Principal component and correlation analyses indicated that the abundances of MPs were related to wind direction, wastewater discharge amount, and tourist and fishing activities. Risk assessments suggested that potential ecological risks induced by MPs on beaches and mangrove forest along the coast of South China should not be overlooked.

MicroRNA-9 facilitates hypoxia-induced injury and apoptosis in H9c2 cells via targeting CDK8.

Hypoxia plays an important role in many heart diseases. MicroRNA-9 (miR-9) has been reported to be involved in hypoxia-induced cell proliferation, injury and apoptosis in cardiomyocytes. However, the underlying mechanism still remains poorly understood. The expression levels of miR-9 and cyclin-dependent kinase 8 (CDK8) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The relative protein expression was measured by Western blot. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT), lactate dehydrogenase (LDH) measurement, flow cytometry assays were conducted to detect cell proliferation, the release of LDH and cell apoptosis, respectively. The potential relationship between miR-9 and CDK8 was predicted by online database, and confirmed by dual-luciferase reporter assay. We found that miR-9 was increased, while CDK8 was decreased in hypoxia-treated H9c2 cells. miR-9 down-regulation or CDK8 up-regulation promoted cell proliferation, while repressed cell damage and apoptosis in hypoxia-induced H9c2 cells. Moreover, CDK8 was identified to be target of miR-9, and CDK8 knockdown could reverse the effects of miR-9 inhibitor on cell proliferation, damage and apoptosis in hypoxia-treated H9c2 cells. Besides, miR-9 could regulate the Wnt/b-catenin pathway by targeting CDK8 in hypoxic-induced H9c2 cells. In conclusion, miR-9 repressed cell proliferation and promoted cell damage and apoptosis by binding to CDK8 through the Wnt/ ß-catenin pathway in hypoxic-induced H9c2 cells, which provided a new direction for further studying the treatment of hypoxia-aroused heart diseases.

Mesenchymal Stem Cells: A New Choice for Nonsurgical Treatment of OA? Results from a Bayesian Network Meta-Analysis.

OBJECTIVE: Osteoarthritis (OA) is the most common degenerative joint disease, causing joint pain, stiffness, and even disability. Guidelines recommend intra-articular injections as an alternative treatment to relieve OA symptoms for patients who demonstrate poor tolerability or compliance to oral administration of drugs. Mesenchymal stem cells (MSCs) are a potential treatment for of OA. We conducted this network meta-analysis to comprehensively compare the efficacy and safety between hyaluronic acid (HA), corticosteroids (GCs), platelet-rich plasma (PRP), and MSCs. DESIGN: Systematic review and Bayesian network meta-analysis. Data Sources. Relevant studies, published from January 2000 to January 2020, in the PubMed, Cochrane library, EMBASE, and CKNI databases. METHODS: Bayesian network and conventional meta-analyses were conducted. Pain relief, functional improvement, improvement in joint stiffness, and risk of adverse effects (AEs) were assessed. RESULTS: Twenty-five articles with 4642 patients were included. Overall, MSC therapy was the most effective treatment for pain relief (standardized mean difference compared with placebo = 3.61, 95% CI [1.87 to 5.35]). Both MSC and PRP therapies improved every symptom of OA effectively and have an advantage over HA and GCs which are recommended by guidelines. MSCs, PRP, HA, and GCs are tolerated well for patients in long-term treatment of OA compared with placebo. CONCLUSIONS: The results show that MSCs relieve pain, stiffness, and dysfunction due to OA better than PRP, HA, and GCs and are not statistically correlated with greater safety concerns. More high-quality trials are needed to reconfirm the findings of this study, however, standardization of preparation of MSCs and PRP should be investigated in the future.

Is Lutikizumab, an Anti-Interleukin-1α/ß Dual Variable Domain Immunoglobulin, efficacious for Osteoarthritis? Results from a bayesian network meta-analysis.

OBJECTIVE: Most guidelines recommend the use of nonsteroidal anti-inflammatory drugs (NSAIDs), duloxetine, and tramadol for the nonoperative treatment of osteoarthritis (OA), but the use of them is limited by the tolerability and safety concerns. Lutikizumab is a novel anti-IL-1α/ß dual variable domain immunoglobulin that can simultaneously bind and inhibit IL-1α and IL-1ß to relieve the pain and dysfunction symptoms. We conducted this network meta-analysis to comprehensively compare the clinical efficacy and safety of lutikizumab with other drugs recommended by guidelines. METHODS: We conducted a Bayesian network and conventional meta-analyses to compare the efficacy and safety of lutikizumab with other traditional drugs. All eligible randomized clinical trials, in PubMed, CNKI, EMBASE, and Web of Science databases, from January 2000 to January 2020, were included. The Cochrane risk of the bias assessment tool was used for quality assessment. Pain relief, function improvement, and risk of adverse effects (AEs) were compared in this study. RESULTS: 24 articles with 11858 patients were included. Duloxetine (DUL) had the largest effect for pain relief (4.76, 95% CI [2.35 to 7.17]), and selective cox-2 inhibitors (SCI) were the most efficacious treatment for physical function improvement (SMD 3.94, 95% CI [2.48 to 5.40]). Lutikizumab showed no benefit compared with placebo for both pain relief (SMD 1.11, 95% CI [-2.29 to 4.52]) and function improvement (SMD 0.992, 95% CI [-0.433 to 4.25]). Lutikizumab and all other drugs are of favorable tolerance for patients in the treatment of OA compared with placebo. CONCLUSIONS: Lutikizumab, the new anti-Interleukin-1α/ß dual variable domain immunoglobulin, showed no improvement in pain or function when compared with placebo. Selective cox-2 inhibitors and duloxetine remain the most effective and safest treatment for OA. More high-quality trials are still needed to reconfirm the findings of this study.

Downregulation of microRNA-29b by DNMT3B decelerates chondrocyte apoptosis and the progression of osteoarthritis via PTHLH/CDK4/RUNX2 axis.

The correlation between DNA methyltransferases (DNMTs) and microRNAs (miRNAs) has been well-established, but its interaction in osteoarthritis (OA) has been barely clarified. This study aimed to analyze the relationship between DNMT3B and miR-29b as well as their implications in OA. Our results revealed that DNMT3B was downregulated while miR-29b was upregulated in OA cartilage tissues relative to normal cartilage tissues. Hypermethylation of specific CpG sites in the miR-29b promoter region induced by DNMT3B contributed to downregulation of miR-29b in OA chondrocytes. Furthermore, luciferase activity determination demonstrated that miR-29b targeted and negatively regulated the parathyroid hormone-like hormone (PTHLH). Moreover, the PTHLH upregulation induced by miR-29b methylation led to the enhancement of chondrocyte growth and suppression of their apoptosis and extracellular matrix degradation, which was achieved by the upregulation cyclin-dependent kinase 4 (CDK4) expression. Co-IP suggested that CDK4 induced ubiquitination of RUNX2, which could be enhanced by DNMT3B. In the OA mouse model induced by destabilization of the medial meniscus, overexpression of DNMT3B was observed to downregulate the expression of RUNX2 whereby preventing OA-induced loss of chondrocytes. Hence, the DNMT3B/miR-29b/PTHLH/CDK4/RUNX2 axis was found to be involved in the apoptosis of chondrocytes induced by OA, highlighting a novel mechanism responsible for OA progression.

Tussilagone Inhibits Osteoclastogenesis and Periprosthetic Osteolysis by Suppressing the NF-κB and P38 MAPK Signaling Pathways.

BACKGROUND: Aseptic prosthetic loosening is one of the main factors causing poor prognosis of limb function after joint replacement and requires troublesome revisional surgery. It is featured by wear particle-induced periprosthetic osteolysis mediated by excessive osteoclasts activated in inflammatory cell context. Some natural compounds show antiosteoclast traits with high cost-efficiency and few side effects. Tussilagone (TUS), which is the main functional extract from Tussilago farfara generally used for relieving cough, asthma, and eliminating phlegm in traditional medicine has been proven to appease several RAW264.7-mediated inflammatory diseases via suppressing osteoclast-related signaling cascades. However, whether and how TUS can improve aseptic prosthetic loosening via modulating osteoclast-mediated bone resorption still needs to be answered. METHODS: We established a murine calvarial osteolysis model to detect the preventative effect of TUS on osteolysis in vivo. Micro-CT scanning and histomorphometric analysis were used to determine the variation of bone resorption and osteoclastogenesis. The anti-osteoclast-differentiation and anti-bone-resorption bioactivities of TUS in vitro were investigated using bone slice resorption pit evaluation, and interference caused by cytotoxicity of TUS was excluded according to the CCK-8 assay results. Quantitative polymerase chain reaction (qPCR) analysis was applied to prove the decreased expression of osteoclast-specific genes after TUS treatment. The inhibitory effect of TUS on NF-κB and p38 MAPK signaling pathways was testified by Western blot and NF-κB-linked luciferase reporter gene assay. RESULTS: TUS better protected bones against osteolysis in murine calvarial osteolysis model with reduced osteoclasts than those in the control group. In vitro studies also showed that TUS exerted antiosteoclastogenesis and anti-bone-resorption effects in both bone marrow macrophages (BMMs) and RAW264.7 cells, as evidenced by the decline of osteoclast-specific genes according to qPCR. Western blotting revealed that TUS treatment inhibited IκBα degradation and p38 phosphorylation. CONCLUSIONS: Collectively, our studies proved for the first time that TUS inhibits osteoclastogenesis by suppressing the NF-κB and p38 MAPK signaling pathways, therefore serving as a potential natural compound to treat periprosthetic osteolysis-induced aseptic prosthetic loosening.

lnc-SAMD14-4 can regulate expression of the COL1A1 and COL1A2 in human chondrocytes.

Osteoarthritis (OA) is the most common motor system disease in aging people, characterized by matrix degradation, chondrocyte death, and osteophyte formation. OA etiology is unclear, but long noncoding RNAs (lncRNAs) that participate in numerous pathological and physiological processes may be key regulators in the onset and development of OA. Because profiling of lncRNAs and their biological function in OA is not understood, we measured lncRNA and mRNA expression profiles using high-throughput microarray to study human knee OA. We identified 2,042 lncRNAs and 2,011 mRNAs that were significantly differentially expressed in OA compared to non-OA tissue (>2.0- or < - 2.0-fold change; p < 0.5), including 1,137 lncRNAs that were upregulated and 905 lncRNAs that were downregulated. Also, 1,386 mRNA were upregulated and 625 mRNAs were downregulated. QPCR was used to validate chip results. Gene Ontology analysis and the Kyoto Encyclopedia of Genes and Genomes was used to study the biological function enrichment of differentially expressed mRNA. Additionally, coding-non-coding gene co-expression (CNC) network construction was performed to explore the relevance of dysregulated lncRNAs and mRNAs. Finally, the gain/loss of function experiments of lnc-SAMD14-4 was implemented in IL-1ß-treated human chondrocytes. In general, this study provides a preliminary database for further exploring lncRNA-related mechnisms in OA.

Targeted delivery of hesperetin to cartilage attenuates osteoarthritis by bimodal imaging with Gd2(CO3)3@PDA nanoparticles via TLR-2/NF-κB/Akt signaling.

The progressive degeneration of cartilage marks the advancement of osteoarthritis (OA), which requires specific targeted treatment for effective cartilage repair. However, there is still no efficient cartilage delivery system or novel magnetic resonance (MR) contrast agent (CA). Herein, we report the synthesis of a novel class of MR CA, Gd2(CO3)3-based nanoparticles (NPs), from a simpler and "greener" approach than previous ones. After the coating of polydopamine (PDA) onto the Gd2(CO3)3 core, we further anchored a cartilage-targeting peptide and loaded hesperetin (Hes) into NPs (Hes-Gd2(CO3)3@PDA-PEG-DWpeptide, HGdPDW), showing excellent cartilage affinity and MR suitability. Additionally, the synthesized HGdPDW exerted significant protective effects against IL-1ß stimulation, as shown by the decreased apoptosis and inflammation and increased maturation of chondrocytes in vitro. More importantly, RNA-seq analyses showed the significant reduction of TLR-2 in IL-1ß-treated chondrocytes, and this reduction was followed by the inactivation of NF-κB/Akt signaling, leading to the protective effect of HGdPDW. By the establishment of anterior cruciate ligament transection (ACLT) OA mice, the bimodal MRI/IVIS imaging demonstrated the effective cartilage-binding ability of HGdPDW in OA knees with low cytotoxicity, which alleviated the gradual degeneration of articular cartilage in vivo by inhibiting TLR-2 in chondrocytes. Taken together, these results suggest that HGdPDW could target cartilage effectively, thereby protecting chondrocytes from apoptosis and inflammation via TLR-2/NF-κB/Akt signaling. We hope this new class of MRI CA could be applied in not only other fields using MRI technology but also the treatment of general cartilage-related diseases; this application will undoubtedly extend the treatment of OA clinically.

A Novel Peptide from Vespa ducalis Induces Apoptosis in Osteosarcoma Cells by Activating the p38 MAPK and JNK Signaling Pathways.

Osteosarcoma (OS) is a typical bone cancer, and most frequently used cancer treatments for OS are limited due to severe drug-related toxicities. Wasp venoms contain functional components that may offer pharmaceutical components for the treatment of cancers. This study aimed to isolate and characterize a novel peptide (venom anti-cancer peptide 1, VACP1) derived from the wasp venom of Vespa ducalis SMITH. Toxins from Vespa ducalis crude venom were separated by gel filtration and purified by C18 reverse-phase HPLC. As examined by Edman degradation, the amino acid sequence of VACP1 is AQKWLKYWKADKVKGFGRKIKKIWFG. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays revealed that VACP1 inhibited the cell proliferation of MG-63, U-2 OS and Saos-2 cells. Furthermore, annexin V and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) staining revealed that VACP1 could induce the apoptosis of OS cell lines. In addition, VACP1 increased the protein levels of cleaved poly ADP-ribose polymerase (PARP), caspase 3, but decreased B-cell lymphoma 2 (Bcl-2). Apoptotic signaling pathway screening in MG-63 cells via an antibody array revealed that VACP1 activated the p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) pathways. The present study demonstrates that VACP1 potently suppressed cell proliferation and induced the cell apoptosis of OS cells by inducing the activation of the p38 MAPK and JNK signaling pathways, suggesting that VACP1 is a promising agent for OS therapy.

Anti-ganglioside GD2 monoclonal antibody synergizes with cisplatin to induce endoplasmic reticulum-associated apoptosis in osteosarcoma cells.

Cisplatin is an effective chemotherapeutic agent for osteosarcoma (OS) and has been shown to induce endoplasmic reticulum (ER) stress-associated apoptosis in human cancer cells. Ganglioside GD2-specific antibodies can inhibit tumor cell viability without involvement of the immune system. A recent study has shown that antiGD2 monoclonal antibody (mAb) 14G2a effectively inhibits the viability and invasiveness of human OS cells. In this study, we explored the effect of anti-GD2 mAb and cisplatin alone and in combination on ER stress-associated apoptosis in osteosarcoma cells. MG-63 and Saos-2 human OS cells were treated with cisplatin and/or an-GD2 mAb 14G2a for 48 hours. Cisplatin and 14G2a dose-dependently induced apoptosis in MG-63 and Saos-2 cells. They in combination induced 70%-77% of apoptosis in MG-63 cells and 79%-85% of apoptosis in Saos-2 cells, exhibiting a synergistic effect stronger than addition of their individual effects over the control level. Showing no significant effect on the expression of protein kinase RNA-like ER kinase (PERK), cisplatin and 14G2a exhibited a marked synergistic effect on inducing phosphorylation/activation of PERK, phosphorylation/inactivation of eukaryotic translation initiation factor 2α (eIF2α), expression of CHOP, in parallel to inducing the caspase-3 activity and apoptosis in MG-63 and Saos-2 cells. The effects were abolished by lentivirus-mediated knockdown of PERK. Particularly, PERK knockdown abolished 63% and 65% of the combined apoptotic effect of cisplatin and 14G2a on MG-63 and Saos-2 cells, respectively. In conclusion, this study provides the first evidence supporting that cisplatin and 14G2a synergize to induce ER stress-associated apoptosis in human OS cells through activating the PERK ER stress pathway by synergistically inducing phosphorylation/activation of PERK. Our findings add new insights into the pharmacologic effects of anti-GD2 mAb in anticancer treatment and suggest that cisplatin plus anti-GD2 mAb could be a new effective therapeutic strategy for OS.

Application of Long Noncoding RNAs in Osteosarcoma: Biomarkers and Therapeutic Targets.

Osteosarcoma is the most common primary bone malignancy in children and adolescents. Although improvements in therapeutic strategies were achieved, the outcome remains poor for most patients with metastatic or recurrent osteosarcoma. Therefore, it is imperative to identify novel and effective prognostic biomarker and therapeutic targets for the disease. Long noncoding RNAs (lncRNAs) are a novel class of RNA molecules defined as transcripts >200 nucleotides that lack protein coding potential. Many lncRNAs are deregulated in cancer and are important regulators for malignancies. Nine lncRNAs (91H, BCAR4, FGFR3-AS1, HIF2PUT, HOTTIP, HULC, MALAT-1, TUG1, UCA1) are upregulated and considered oncogenic for osteosarcoma. Loc285194 and MEG3 are two lncRNAs downregulated and as tumor suppressor for the disease. Moreover, the expressions of LINC00161 and ODRUL are associated with chemo-resistance of osteosarcoma. The mechanisms for these lncRNAs in regulating development of osteosarcoma are diverse, e.g. ceRNA, Wnt/ß-catenin pathway, etc. The lncRNAs identified may serve as potential biomarkers or therapeutic targets for osteosarcoma.

Long non-coding RNA HOTAIR promotes expression of ADAMTS-5 in human osteoarthritic articular chondrocytes.

Accumulating evidence indicated that inhibiting the expression of a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-5 ameliorate cartilage degradation, suggesting ADAMTS-5 as an effective target for treating osteoarthritis (OA). A recent study has identified long noncoding RNA (lncRNA) HOTAIR and ADAMTS-5 as the most up-regulated lncRNA and the most upregulated gene, respectively, in human OA cartilage compared with normal cartilage. In the present study, we explored the regulatory effect of HOTAIR on the expression of ADAMTS-5 as well as the underlying mechanisms in human normal and OA articular chondrocytes. We found that human OA articular chondrocytes had significantly higher basal expression levels of HOTAIR and ADAMTS-5 than normal articular chondrocytes. Tumor necrosis factor (TNF)-α significantly enhanced the basal expression of HOTAIR and ADAMTS-5 in OA but not in normal articular chondrocytes. Lentiviral overexpression and knockdown of HOTAIR markedly increased and decreased the expression of ADAMTS-5, respectively, in OA but not in normal articular chondrocytes in the presence or absence of TNF-α. Neither overexpression/ knockdown of HOTAIR nor TNF-α showed a significant effect on the ADAMTS-5 gene promoter in OA articular chondrocytes. Although HOTAIR showed no significant effect on the stability of ADAMTS-5 mRNA in normal articular chondrocytes, HOTAIR overexpression and knockdown respectively increased and decreased the ADAMTS-5 mRNA stability in OA articular chondrocytes. TNF-α enhanced the protective effect of HOTAIR on the ADAMTS-5 mRNA stability. In conclusion, this study provides the first evidence supporting that HOTAIR strongly promotes the expression of ADAMTS-5 by increasing its mRNA stability in human OA articular chondrocytes; this effect is enhanced by TNF-α. It adds new insights into the pathogenesis of OA and suggests that HOTAIR could be a new therapeutic target for ADAMTS-5 inhibition in human OA cartilage.

Finite element prediction of contact pressures in cam-type femoroacetabular impingement with varied alpha angles.

Three dimensional finite element models of cam-type FAI with alpha angles of 60°, 70°, 80°, and 90° were created to investigate the cartilage contact mechanics in daily activities. Intra-articular cartilage contact pressures during routine daily activities were assessed and cross-compared with a normal control hip. Alpha angles and hip range of motion were found to have a combined influence on the cartilage contact mechanics in hips with cam-type FAI, thereby resulting in abnormally high pressures and driving the cartilage damage. In particular, alpha angles of 80° or greater contribute to substantial pressure increase under certain types of daily activities.

Osthole ameliorates acute myocardial infarction in rats by decreasing the expression of inflammatory-related cytokines, diminishing MMP-2 expression and activating p-ERK.

Osthole, the active constituent of Cnidium monnieri extracts, has been shown to have a diverse range of pharmacological properties. In the present study, we aimed to evaluate the cardioprotective effects of osthole in a rat model of acute myocardial infarction (AMI). The rats with AMI were treated with 1, 3 and 10 mg/kg of osthole or the vehicle for 4 weeks. The infarct size of the rats with AMI was measured, and casein kinase (CK), the MB isoenzyme of creatine kinase (CK-MB), lactate dehydrogenase (LDH) and cardiac troponin T (cTnT) activities in the rats with AMI were analyzed using commercially available kits. The nuclear factor-κB (NF-κB), tumor necrosis factor­α (TNF-α), interleukin (IL)-1ß and IL-6 levels in whole blood from rats with AMI were also detected using commercially available kits. The levels of Toll-like receptors 2/4 (TLR2/4) and nucleotide-binding oligomerization domain-containing protein 1/2 (NOD1/2) were also detected by RT-qPCR. Moreover, the protein expression levels of endothelial nitric oxide synthase (eNOS) and mitogen-activated protein kinase (MAPK) cascades, including extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38, cyclooxygenase-2 (COX-2), as well as matrix metalloproteinase-2 (MMP-2) were all assayed by western blot analysis. Our results revealed that osthole markedly reduced the infarct size, and the levels of CK, CK-MB, LDH and cTnT in the rats with AMI, and that these cardioprotective effects may be associated with the inhibition of inflammatory reactions, the reduction in MMP-2 activity and the activation of MAPK cascades.