Time trajectories and within-subject correlations of matrix metalloproteinases 3, 8, 9, 10, 12, and 13 serum levels and their ability to predict mortality in polytraumatized patients: a pilot study

BACKGROUND

Managing polytrauma victims poses a significant challenge to clinicians since applying the same therapy to patients with similar injury patterns may result in different outcomes. Using serum biomarkers hopefully allows for treating each multiple injured in the best possible individual way. Since matrix metalloproteinases (MMPs) play pivotal roles in various physiological processes, they might be a reliable tool in polytrauma care.

METHODS

We evaluated 24 blunt polytrauma survivors and 12 fatalities (mean age, 44.2 years, mean ISS, 45) who were directly admitted to our Level I trauma center and stayed at the intensive care unit for at least one night. We determined their MMP3, MMP8, MMP9, MMP10, MMP12, and MMP13 serum levels at admission (day 0) and on days 1, 3, 5, 7, and 10.

RESULTS

Median MMP8, MMP9, and MMP12 levels immediately rose after the polytrauma occurred; however, they significantly decreased from admission to day 1 and significantly increased from day 1 to day 10, showing similar time trajectories and (very) strong correlations between each two of the three enzyme levels assessed at the same measurement point. For a two-day lag, autocorrelations were significant for MMP8 (- 0.512) and MMP9 (- 0.302) and for cross-correlations between MMP8 and MMP9 (- 0.439), MMP8 and MMP12 (- 0.416), and MMP9 and MMP12 (- 0.307). Moreover, median MMP3, MMP10, and MMP13 levels significantly increased from admission to day 3 and significantly decreased from day 3 to day 10, showing similar time trajectories and an (almost) strong association between every 2 levels until day 7. Significant cross-correlations were detected between MMP3 and MMP10 (0.414) and MMP13 and MMP10 (0.362). Finally, the MMP10 day 0 level was identified as a predictor for in-hospital mortality. Any increase of the MMP10 level by 200 pg/mL decreased the odds of dying by 28.5%.

CONCLUSIONS

The time trajectories of the highly varying individual MMP levels elucidate the involvement of these enzymes in the endogenous defense response following polytrauma. Similar time courses of MMP levels might indicate similar injury causes, whereas lead-lag effects reveal causative relations between several enzyme pairs. Finally, MMP10 abundantly released into circulation after polytrauma might have a protective effect against dying.

Periodontitis exacerbation during pregnancy in mice: Role of macrophage migration inhibitory factor as a key inductor

OBJECTIVE

The present study was designed to investigate the role of macrophage migration inhibitory factor (MIF) in the exacerbation of pregestational periodontal disease (PGPD).

BACKGROUND

Periodontitis (PT) is a severe stage of periodontal disease characterized by inflammation of the supporting tissues of the teeth, which usually worsens during pregnancy. MIF is a proinflammatory cytokine that is significantly elevated in periodontitis, both at the beginning and at the end of pregnancy. Although periodontitis usually presents with greater severity during pregnancy, the participation of MIF in the evolution of periodontitis has not been established.

METHODS

To analyze the relevance of MIF in the exacerbation of PGPD, we employed a model of PGPD in WT and Mif-/- mice, both with a BALB/c genetic background. PT was induced with nylon suture ligatures placed supramarginally around the second upper right molar. For PGPD, PT was induced 2 weeks before mating. We evaluated histological changes and performed histometric analysis of the clinical attachment loss, relative expression of MMP-2 and MMP-13 by immunofluorescence, and relative expression of the cytokines mif, tnf-α, ifn-γ, and il-17 by quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTS

Our data revealed that periodontal tissue from PGPD WT mice produced a twofold increase in MIF compared with PT WT mice. Moreover, the evolution of periodontitis in Mif-/- mice was less severe than in PGDP WT mice. Periodontal tissue from Mif-/- mice with PGPD produced 80% less TNF-α and no IFN-γ, as well as 50% lower expression of matrix metalloproteinase (MMP)-2 and 25% less MMP-13 compared to WT PGDP mice.

CONCLUSIONS

Our study suggests that MIF plays an important role in the exacerbation of periodontitis during pregnancy and that MIF is partially responsible for the inflammation associated with the severity of periodontitis during pregnancy.

The complement factor H-related protein-5 (CFHR5) exacerbates pathological bone formation in ankylosing spondylitis

Ankylosing spondylitis (AS) is a chronic inflammatory disease, characterized by excessive new bone formation. We previously reported that the complement factor H-related protein-5 (CFHR5), a member of the human factor H protein family, is significantly elevated in patients with AS compared to other rheumatic diseases. However, the pathophysiological mechanism underlying new bone formation by CFHR5 is not fully understood. In this study, we revealed that CFHR5 and proinflammatory cytokines (TNF, IL-6, IL-17A, and IL-23) were elevated in the AS group compared to the HC group. Correlation analysis revealed that CFHR5 levels were not significantly associated with proinflammatory cytokines, while CFHR5 levels in AS were only positively correlated with the high CRP group. Notably, treatment with soluble CFHR5 has no effect on clinical arthritis scores and thickness at hind paw in curdlan-injected SKG, but significantly increased the ectopic bone formation at the calcaneus and tibia bones of the ankle as revealed by micro-CT image and quantification. Basal CFHR5 expression was upregulated in AS-osteoprogenitors compared to control cells. Also, treatment with CFHR5 remarkedly induced bone mineralization status of AS-osteoprogenitors during osteogenic differentiation accompanied by MMP13 expression. We provide the first evidence demonstrating that CFHR5 can exacerbate the pathological bone formation of AS. Therapeutic modulation of CFHR5 could be promising for future treatment of AS. KEY MESSAGES: Serum level of CFHR5 is elevated and positively correlated with high CRP group of AS patients. Recombinant CFHR5 protein contributes to pathological bone formation in in vivo model of AS. CFHR5 is highly expressed in AS-osteoprogenitors compared to disease control. Recombinant CFHR5 protein increased bone mineralization accompanied by MMP13 in vitro model of AS.

CXCL8, MMP12, and MMP13 are common biomarkers of periodontitis and oral squamous cell carcinoma

OBJECTIVE

To analysis the relationship between periodontitis (PD) and oral squamous cell carcinoma (OSCC) by bioinformatic analysis.

MATERIALS AND METHODS

We analyzed the gene expression profiles of PD (GSE16134) from the Gene Expression Omnibus (GEO) database and OSCC samples from TCGA-HNSC (head and neck squamous cell carcinoma) and identified common differentially expressed genes (DEGs) in PD and OSCC. Then, functional annotation and signaling pathway enrichment, protein interaction network construction, and hub gene identification were performed. Subsequently, the function and signaling pathway enrichment of hub genes, miRNA interaction, and transcription factor interaction analyses were carried out. We analyzed GSE10334 and GSE30784 as validation datasets, and performed qRT-PCR experiments simultaneously for validation, and obtained 4 hub genes. Finally, immune infiltration analysis and clinical correlation analysis of 4 hub genes and related miRNAs were performed.

RESULTS

We identified 31 DEGs (16 up-regulated and 15 down-regulated). Four hub genes were obtained by qRT-PCR and validation dataset analysis, including IL-1β, CXCL8, MMP12, and MMP13. The expression levels of them were all significantly upregulated in both diseases. The functions of these genes focus on three areas: neutrophil chemotaxis, migration, and CXCR chemokine receptor binding. Key pathways include IL-17 signaling pathway, chemokine signaling pathway, and cytokine-cytokine receptor interactions pathway. Immune infiltration analysis showed that the expressions of 4 hub genes were closely related to a variety of immune cells. ROC curve analysis indicated that AUCs of 4 hub genes are all greater than 0.7, among which MMP12 and MMP13 were greater than 0.9. Kaplan-Meier survival analysis indicated that worse OS was strongly correlated with CXCL8 and MMP13 high-expression groups. MMP12 low-expression group was strongly associated with worse OS. The results of multivariate Cox regression analysis showed that age, N stage, CXCL8, MMP12, and MMP13 were independent prognostic factors for OS. We also identified 3 miRNAs, including hsa-miR-19b-3p, hsa-miR-181b-2-3p, and hsa-miR-495-3p, that were closely related to 4 hub genes. Hsa-miR-495-3p is closely related to the diagnosis and prognosis of OSCC.

CONCLUSIONS

We identified 4 hub genes between PD and OSCC, including IL-1β, CXCL8, MMP12, and MMP13. These genes may mediate the co-morbid process of PD and OSCC through inflammation-related pathways such as the IL-17 signaling pathway. It is worth noting that CXCL8, MMP12, and MMP13 have great significance in the diagnosis and prognosis of OSCC.

Identification and Verification of Novel Biomarkers Involving Rheumatoid Arthritis with Multimachine Learning Algorithms: An In Silicon and In Vivo Study

Background

Rheumatoid arthritis (RA) remains one of the most prevalent chronic joint diseases. However, due to the heterogeneity among RA patients, there are still no robust diagnostic and therapeutic biomarkers for the diagnosis and treatment of RA.

Methods

We retrieved RA-related and pan-cancer information datasets from the Gene Expression Omnibus and The Cancer Genome Atlas databases, respectively. Six gene expression profiles and corresponding clinical information of GSE12021, GSE29746, GSE55235, GSE55457, GSE77298, and GSE89408 were adopted to perform differential expression gene analysis, enrichment, and immune component difference analyses of RA. Four machine learning algorithms, including LASSO, RF, XGBoost, and SVM, were used to identify RA-related biomarkers. Unsupervised cluster analysis was also used to decipher the heterogeneity of RA. A four-signature-based nomogram was constructed and verified to specifically diagnose RA and osteoarthritis (OA) from normal tissues. Consequently, RA-HFLS cell was utilized to investigate the biological role of CRTAM in RA. In addition, comparisons of diagnostic efficacy and biological roles among CRTAM and other classic biomarkers of RA were also performed.

Results

Immune and stromal components were highly enriched in RA. Chemokine- and Th cell-related signatures were significantly activated in RA tissues. Four promising and novel biomarkers, including CRTAM, PTTG1IP, ITGB2, and MMP13, were identified and verified, which could be treated as novel treatment and diagnostic targets for RA. Nomograms based on the four signatures might aid in distinguishing and diagnosing RA, which reached a satisfactory performance in both training (AUC = 0.894) and testing (AUC = 0.843) cohorts. Two distinct subtypes of RA patients were identified, which further verified that these four signatures might be involved in the immune infiltration process. Furthermore, knockdown of CRTAM could significantly suppress the proliferation and invasion ability of RA cell line and thus could be treated as a novel therapeutic target. CRTAM owned a great diagnostic performance for RA than previous biomarkers including MMP3, S100A8, S100A9, IL6, COMP, LAG3, and ENTPD1. Mechanically, CRTAM could also be involved in the progression through immune dysfunction, fatty acid metabolism, and genomic instability across several cancer subtypes.

Conclusion

CRTAM, PTTG1IP, ITGB2, and MMP13 were highly expressed in RA tissues and might function as pivotal diagnostic and treatment targets by deteriorating the immune dysfunction state. In addition, CRTAM might fuel cancer progression through immune signals, especially among RA patients.

Mechanism of pro-MMP9 activation in co-culture of pro-inflammatory macrophages and cardiomyocytes

OBJECTIVE

A wide range of cardiac diseases is associated with inflammation. "Inflamed" heart tissue is infiltrated with pro-inflammatory macrophages which extensively secrete matrix metalloproteinase 9 (MMP9), a regulator of extracellular matrix turnover. As MMP9 is released from macrophages in a latent form, it requires activation. The present study addresses the role of cardiomyocytes in the course of this activation process.

METHODS AND RESULTS

In mono- and co-cultures of pro-inflammatory rat macrophages (bone marrow-derived and peritoneal) and cardiomyocytes (H9C2 cell line) gelatin zymography demonstrated that activated macrophages robustly secreted latent pro-MMP9, whereas cardiomyocytes could not produce the enzyme. Co-culturing of the two cell species was critical for pro-MMP9 activation and was also accompanied by processing of cardiomyocyte-secreted pro-MMP2. A cascade of pro-MMP9 activation was initiated on macrophage membrane with pro-MMP2 cleavage. Namely, pro-inflammatory macrophages expressed an active membrane type 1 MMP (MT1MMP), which activated pro-MMP2, which in turn converted pro-MMP9. Downregulation of MT1MMP in macrophages by siRNA abolished activation of both pro-MMP2 and pro-MMP9 in co-culture. In addition, both cell species secreted MMP13 as a further pro-MMP9 activator. In co-culture, activation of pro-MMP13 occurred on membranes of macrophages and was enhanced in presence of active MMP2. Using incubations with recombinant MMPs and isolated macrophage membranes, we demonstrated that while both MMP2 and MMP13 individually had the ability to activate pro-MMP9, their combined action provided a synergistic effect.

CONCLUSION

Activation of pro-MMP9 in a co-culture of pro-inflammatory macrophages and cardiomyocytes was the result of a complex interaction of several MMPs on the cell membrane and in the extracellular space. Both cell types contributed critically to pro-MMP9 processing.

TGF-β1 Inhibits Osteoclast Differentiation and Abnormal Angiogenesis in Intervertebral Disc Degeneration: Evidence from RNA Sequencing and Animal Studies

OBJECTIVE

Mechanisms involved in developing intervertebral disc degeneration (IDD) are poorly understood, thus making developing effective therapies difficult. This study aimed to suggest a possible molecular mechanism, based on transcriptome sequencing-identified transforming growth factor (TGF-β), underlying the effects on bone homeostasis in IDD.

METHODS

A mouse model for IDD was established. Transcriptome sequencing of nucleus pulposus tissue from mice (n = 3) identified differentially expressed mRNAs and key genes impacting bone homeostasis. A protein-protein interaction network pinpointed core genes. GO and KEGG analysis revealed gene functions. Expression levels of TGF-β1, tartrate-resistant acid phosphatase (TRAP), and cathepsin K (CTSK) were measured. Micro-CT evaluated vertebral structures and vascular imaging. Western Blot measured expression levels of Vegf, Opn, MMP3, and MMP13. Safranin O-Fast Green and TRAP staining were performed on intervertebral discs and endplates.

RESULTS

Transcriptomic analysis found 1790 differentially expressed mRNAs in IDD mice. Twenty-eight genes related to bone homeostasis in IDD were identified. TGF-β1 was confirmed as the core gene. GO and KEGG showed TGF-β1 regulates osteoclast markers like CTSK and TRAP through pathways including NF-κB and MAPK. Experimental validation revealed lower TGF-β1 expression in IDD mice than controls, and increased TRAP and CTSK expression. Micro-CT showed decreased bone mass and intervertebral disc space in IDD mice. Vascular imaging showed increased vascular volume in IDD cartilaginous endplates. Western blot displayed increased VEGF and OPN levels, but decreased MMP3 and MMP13 in IDD mice. Safranin O-fast green staining revealed severe IDD degeneration. However, TGF-β1 injection improved bone parameters in IDD mice. In vitro experiments confirmed TGF-β1 inhibits bone marrow macrophages differentiation into osteoclasts.

CONCLUSION

From our data, we conclude that TGF-β1 repressed osteoclast differentiation and aberrant bone-associated angiogenesis in cartilage endplates (EPs) to alleviate IDD, which may be instrumental for the therapeutic targeting of IDD.

Hsa_circ_0004662 Accelerates the Progression of Osteoarthritis via the microRNA-424-5p/VEGFA Axis

OBJECTIVE

Circular RNAs (circRNAs) have been extensively implicated in osteoarthritis (OA) progression. Therefore, this study explores the impact of hsa_circ_0004662 on OA progression and the related molecular mechanism.

METHODS

Human articular chondrocyte injury was induced by IL-1β to construct the OA model in vitro. Hsa_circ_0004662 and microRNA (miR)-424-5p expression in chondrocytes was evaluated with qRT-PCR. Vascular endothelial growth factors A (VEGFA) expression was examined with qRT-PCR and western blot after hsa_circ_0004662 knockdown or miR-424-5p overexpression in chondrocytes. Subsequent to loss- and gain-of-function assays in IL-1β-induced chondrocytes, the proliferation and apoptosis of chondrocytes were assessed with CCK-8 assay and flow cytometry, respectively. The expression of MMP13, Aggrecan, and apoptosis-related proteins Bax and Bcl-2 was measured with western blot. The binding of miR-424-5p to hsa_circ_0004662 and VEGFA was assessed with a dual-luciferase reporter gene assay.

RESULTS

Hsa_circ_0004662 was up-regulated, but miR-424-5p was down-regulated in IL-1β-induced chondrocytes. Mechanistically, both hsa_circ_0004662 and VEGFA bound to miR-424-5p, and hsa_circ_0004662 enhanced VEGFA expression by downregulating miR-424-5p. Hsa_circ_0004662 knockdown elevated cell proliferation, decreased apoptosis and MMP13 and Bax expression, and increased Aggrecan and Bcl- 2 expression in IL-1β-induced chondrocytes, which was counteracted by further miR- 424-5p down-regulation or VEGFA overexpression.

CONCLUSION

Hsa_circ_0004662 facilitates OA progression via the miR-424-5p/ VEGFA axis.

Multidimensional analysis to elucidate the possible mechanism of bone metastasis in breast cancer

BACKGROUND

Breast cancer (BC) patients tend to suffer from distant metastasis, especially bone metastasis.

METHODS

All the analysis based on open-accessed data was performed in R software, dependent on multiple algorithms and packages. The RNA levels of specific genes were detected using quantitative Real-time PCR as a method of detecting the RNA levels. To assess the ability of BC cells to proliferate, we utilized the CCK8 test, colony formation, and the 5-Ethynyl-20-deoxyuridine assay. BC cells were evaluated for invasion and migration by using Transwell assays and wound healing assays.

RESULTS

In our study, we identified the molecules involved in BC bone metastasis based on the data from multiple BC cohorts. Then, we comprehensively investigated the effect pattern and underlying biological role of these molecules. We found that in the identified molecules, the EMP1, ACKR3, ITGA10, MMP13, COL11A1, and THY1 were significantly correlated with patient prognosis and mainly expressed in CAFs. Therefore, we explored the CAFs in the BC microenvironment. Results showed that CAFs could activate multiple carcinogenic pathways and most of these pathways play an important role in cancer metastasis. Meanwhile, we noticed the interaction between CAFs and malignant, endothelial, and M2 macrophage cells. Moreover, we found that CAFs could induce the remodeling of the BC microenvironment and promote the malignant behavior of BC cells. Then, we identified MMP13 for further analysis. It was found that MMP13 can enhance the malignant phenotype of BC cells. Meanwhile, biological enrichment and immune infiltration analysis were conducted to present the effect pattern of MMP13 in BC.

CONCLUSIONS

Our result can improve the understanding of researchers on the underlying mechanisms of BC bone metastasis.

Battling colorectal cancer via s-triazine-based MMP-10/13 inhibitors armed with electrophilic warheads for concomitant ferroptosis induction; the first-in-class dual-acting agents

There is an increasing interest in halting CRC by combining ferroptosis with other forms of tumor cell death. However, ferroptosis induction is seldom studied in tandem with inhibiting MMPs. A combination that is expected to enhance the therapeutic outcome based on mechanistic ferroptosis studies highlighting the interplay with MMPs, especially MMP-13 associated with CRC metastasis and poor prognosis. Herein, we report new hybrid triazines capable of simultaneous MMP-10/13 inhibition and ferroptosis induction bridging the gap between their anticancer potentials. The MMP-10/13 inhibitory component of the scaffold was based on the non-hydroxamate model inhibitors. s-Triazine was rationalized as the core inspired by altretamine, an FDA-approved ferroptosis inducer. The ferroptosis pharmacophores were then installed as Michael acceptors via triazole-based spacers. The electrophilic reactivity was tuned by incorporating cyano and/or substituted phenyl groups influencing their electronic and steric properties and enriching the SAR study. Initial screening revealed the outstanding cytotoxicity profiles of the nitrophenyl-tethered chalcone 5e and the cyanoacrylohydrazides bearing p-fluorophenyl 9b and p-bromophenyl 9d appendages. 9b and 9d surpassed NNGH against MMP-10 and -13, especially 9d (IC50 = 0.16 μM). Ferroptosis studies proved that 9d depleted GSH in HCT-116 cells by a relative fold decrement of 0.81 with modest direct GPX4 inhibition, thus inducing lipid peroxidation, the hallmark of ferroptosis, by 1.32 relative fold increment. Docking presumed that 9d could bind to the MMP-10 S1' pocket and active site His221, extend through the MMP-13 hydrophobic pocket, and interact covalently with the GPX4 catalytic selenocysteine. 9d complexed with ferrous oxide nanoparticles was 7.5 folds more cytotoxic than its free precursor against HCT-116 cells. The complex-induced intracellular iron overload, depleted GSH with a relative fold decrement of 0.12, consequently triggering lipid peroxidation and ferroptosis by a 3.94 relative fold increment. Collectively, 9d could be a lead for tuning MMPs selectivity and ferroptosis induction potential to maximize the benefit of such a combination.

[Effect of ultrasonic curettage combined with sodium hyaluronate gel on chronic periodontitis and its effect on inflammatory factors hs-CRP, MCP-1 and MMP-13 in gingival crevicular fluid]

PURPOSE

To investigate the effect of ultrasonic curettage combined with sodium hyaluronate gel in the treatment of chronic periodontitis (CP) and the effect on inflammatory factor hypersensitive C-reactive protein (hs-CRP), monocyte chemotactic protein 1 (MCP-1) and matrix metalloproteinase 13 (MMP-13) in gingival crevicular fluid.

METHODS

A total of 102 patients with CP from October 2021 to October 2022 were selected, divided into experimental group (n=51) and control group (n=51) by random number table method. The control group received ultrasonic subgingival curetage, and the experimental group received sodium hyaluronate gel adjuvant therapy on the basis of the control group. The periodontal rehabilitation indexes, clinical efficacy and the changes of gingival crevicular fluid hs-CRP, MCP-1 and MMP-13 were compared between the two groups. The periodontal pathogens, bone metabolism indexes and the occurrence of adverse events during treatment were compared between the two groups. The data were statistically analyzed using SPSS 22.0 software package.

RESULTS

After treatment, the sulcus bleeding index (SBI), gingival index (GI), plaque index (PLI), periodontal pocket depth (PD) and attachment level (AL) of the two groups were significantly lower than before treatment (P＜0.05), and even significantly lower(P＜0.05) in the experimental group. Total effective rate of the experimental group was significantly higher than that of the control group(P＜0.05). hs-CRP, MCP-1 and MMP-13 in both groups after treatment were significantly lower than before treatment(P＜0.05), and hs-CRP, MCP-1 and MMP-13 in the experimental group after treatment were significantly lower than those in the control group(P＜0.05). The detection rates of Porphyromonas gingivalis, Forsetanella and Treponema dentalis were significantly lower in both groups after treatment than before treatment (P＜0.05), and the detection rates of the above indexes in the experimental group after treatment were significantly lower than those in the control group(P＜0.05). After treatment, the C-terminal peptide(CTX) of type Ⅰ collagen was significantly lower than that before treatment, and bone gla protein(BGP) was significantly higher than that before treatment(P＜0.05). The CTX and BGP of the experimental group were significantly lower than that of the control group and significantly higher than that of the control group(P＜0.05). There was no significant difference in the incidence of total adverse reactions between the two groups(P＞0.05). CONCLUSIONS：Ultrasonic curettage combined with sodium hyaluronate gel in the treatment of CP can promote periodontal tissue rehabilitation, enhance short-term efficacy, inhibit synthesis of inflammatory factors in gingival crevicular fluid, kill periodontal pathogens, regulate bone metabolism, and is safe and reliable.

Presence of host and bacterial-derived collagenolytic proteases in carious dentin: a systematic review of ex vivo studies

Introduction and aim

The presence of host collagenases in the degradation of the protein matrix at later stages of carious dentin lesions development, as well as the potential involvement of bacterial collagenases, have been suggested but lack conclusive evidence. This study aims to conduct a systematic review to comprehensively assess the profile of host and bacterial-derived collagenolytic proteases in both root and coronal dentin carious lesions.

Methods

The search was performed in eight databases and the grey literature. Studies evaluating ex vivo dentin, extracted teeth, or biofilms from natural caries lesions were included. The methodological quality of studies was assessed using the Joanna Briggs Institute tool. Synthesis of the results and the certainty of evidence were performed following the Synthesis without Meta-analysis (SWiM) checklist and GRADE approach for narrative synthesis, respectively.

Results

From 935 recovered articles, 18 were included. Although the evidence was very uncertain, it was possible to suggest that 1) MMP-2, MMP-9, MMP-13, and CT-B may be increased in carious dentin when compared to sound dentin; 2) there is no difference in MMP-2 presence, while MMP-13 may be increased in root when compared to coronal carious dentin; 3) there is no difference of MMP-2 and MMP-9 expression/activity before and after cavity sealing; 4) MMP-8 may be increased in the dentin before cavity sealing compared to dentin after cavity sealing; 5) there is no difference of MMP-20 in irradiated vs. non-irradiated carious dentin. MMP-20 probably reduces in carious outer dentin when compared to carious inner dentin (moderate certainty). Genes encoding bacterial collagenolytic proteases and protein-degrading bacteria were detected in coronal and root carious lesions.

Conclusion

Trends in the direction of the effect were observed for some collagenolytic proteases in carious dentin, which may represent a potential target for the development of new treatments. (Protocol register-PROSPERO: CRD42020213141).

[Emodin alleviates joint inflammation and bone erosion in rats with collagen-induced arthritis by inhibiting ferroptosis and degrading matrix metalloproteinases]

OBJECTIVE

To investigate the osteoprotective mechanism of emodin in light of the ferroptosis signaling pathway in a rat model of rheumatoid arthritis.

METHODS

SD rat models of collagen-induced arthritis (CIA) were treated with methotrexate or low or high doses of emodin, and the changes in arthritis scores and toe volume were recorded. model of CIA rats. Malondialdehyde (MDA) content in the joint cartilage was determined, and ankle joint tissue pathologies were observed using caffein solid green staining and hematoxylin-spermine red staining. MMP3 and MMP13 expressions in the ankle joint tissues were detected using immunohistochemistry, and Western blotting was used to detect the protein expressions of ACSL4, SLC7A11, GPX4, and FTH1.

RESULTS

Compared with the normal control rats, the CIA rats showed significantly increased arthritis score index with obvious toe swelling (P<0.05), rough cartilage surface, and loss and irregular aligment of chondrocytes. The rat models also showed significantly increased MDA and ACSL4 contents, lowered SLC7A11, GPX4, and FTH1 contents (P<0.05), and decreased expressions of MMP3 and MMP13 in the ankle joint (P<0.05). The rat models treated with either methotrexate or emodin (40 and 80 mg/kg) had significantly reduced arthritis score index and toe swelling with smooth cartilage surface and neat arrangement of the chondrocytes. The treatments with methotrexate and emodin both decreased the contents of MDA and ACSL4 and increased the contents of SLC7A11, GPX4, and FTH1 in the joint tissues (P<0.05).

CONCLUSION

Emodin can effectively control joint inflammation and improve joint bone erosion in CIA rats possibly by inhibiting the ferroptosis signaling pathways and reducing the expressions of MMP3 and MMP13.

Ecliptasaponin A attenuates renal fibrosis by regulating the extracellular matrix of renal tubular cells

Renal fibrosis is the most common manifestation of end-stage renal disease (ESRD), including diabetic kidney disease (DKD), but there is no effective treatment in renal fibrosis. Natural products are a rich source of clinical drug research and have been used in the clinical research of various diseases. In this study, we searched for traditional Chinese medicine monomers that attenuate fibrosis and assessed their effect on the fibrosis marker connective tissue growth factor (CTGF) in cells which we found ecliptasaponin A. Subsequently, we evaluated the effect of ecliptasaponin A on renal fibrosis in the classic renal fibrosis unilateral ureteral obstruction (UUO) mouse model and found that ecliptasaponin A could reduce the renal collagen fiber deposition and renal extracellular matrix (ECM) protein expression in UUO mice. In vitro, ecliptasaponin A can inhibit ECM protein expression in human kidney-2 (HK-2) cells induced by transforming growth factor-beta1 (TGFβ1). To further clarify the mechanism of ecliptasaponin A in attenuating renal fibrosis, we performed transcriptome sequencing of HK-2 cells treated with TGFβ1 and ecliptasaponin A. The functions and pathways were mainly enriched in the extracellular matrix and TGFβ signalling pathway. Matrix metalloproteinase 10 (MMP10) and matrix metalloproteinase 13 (MMP13) are the main differentially expressed genes in extracellular matrix regulation. Then, we measured MMP10 and MMP13 in the cells and found that ecliptasaponin A had a significant inhibitory effect on MMP13 expression but not on MMP10 expression. Furthermore, we overexpressed MMP13 in HK-2 cells treated with TGFβ1 and found that MMP13 promoted HK-2 cell injury. Our findings suggest that ecliptasaponin A can attenuate renal fibrosis, which may provide a new method for treating renal fibrosis clinically.

A novel immune-related prognostic signature based on Chemoradiotherapy sensitivity predicts long-term survival in patients with esophageal squamous cell carcinoma

Background

There is a heterogenous clinical response following chemoradiotherapy (CRT) in esophageal squamous cell carcinoma (ESCC). Therefore, we aimed to study signaling pathway genes that affect CRT sensitivity and prognosis.

Methods

Gene expression analyses were performed in the GEO and TCGA datasets. A immunohistochemistry (IHC) analysis was performed in pretreatment biopsies.

Results

MMP13 was found to be highly expressed in the "Pathologic Complete Response (pCR)" and "Complete Remission (CR)" and "Alive" groups. Th17 cells and MMP9/13 showed a negative correlation in immune infiltration analysis. In GSEA analysis, IL-4 and IL-13 signaling pathways were highly enriched in patients exhibiting high MMP expression in pCR and CR groups. IHC results suggested higher MMP13 & IL-4 and lower IL-17A & RORC expression in the CR group compared to the 0.70, and the model could well distinguish high-risk and low-risk subgroups.

Conclusion

The above results may provide guidance for developing novel treatment and prognostic strategies in ESCC patients.

[Injectable hydrogel microspheres experimental research for the treatment of osteoarthritis]

Objective

To prepare a novel hyaluronic acid methacrylate (HAMA) hydrogel microspheres loaded polyhedral oligomeric silsesquioxane-diclofenac sodium (POSS-DS) patricles, then investigate its physicochemical characteristics and in vitro and in vivo biological properties.

Methods

Using sulfhydryl POSS (POSS-SH) as a nano-construction platform, polyethylene glycol and DS were chemically linked through the "click chemistry" method to construct functional nanoparticle POSS-DS. The composition was analyzed by nuclear magnetic resonance spectroscopy and the morphology was characterized by transmission electron microscopy. In order to achieve drug sustained release, POSS-DS was encapsulated in HAMA, and hybrid hydrogel microspheres were prepared by microfluidic technology, namely HAMA@POSS-DS. The morphology of the hybrid hydrogel microspheres was characterized by optical microscope and scanning electron microscope. The in vitro degradation and drug release efficiency were observed. Cell counting kit 8 (CCK-8) and live/dead staining were used to detect the effect on chondrocyte proliferation. Moreover, a chondrocyte inflammation model was constructed and cultured with HAMA@POSS-DS. The relevant inflammatory indicators, including collagen type Ⅱ, aggrecan (AGG), matrix metalloproteinase 13 (MMP-13), recombinant A disintegrin and metalloproteinase with thrombospondin 5 (Adamts5), and recombinant tachykinin precursor 1 (TAC1) were detected by immunofluorescence staining and real-time fluorescence quantitative PCR, with normal cultured chondrocytes and the chondrocyte inflammation model without treatment as control group and blank group respectively to further evaluate their anti-inflammatory activity. Finally, by constructing a rat model of knee osteoarthritis, the effectiveness of HAMA@POSS-DS on osteoarthritis was evaluated by X-ray film and Micro-CT examination.

Results

The overall particle size of POSS-DS nanoparticles was uniform with a diameter of about 100 nm. HAMA@POSS-DS hydrogel microspheres were opaque spheres with a diameter of about 100 μm and a spherical porous structure. The degradation period was 9 weeks, during which the loaded POSS-DS nanoparticles were slowly released. CCK-8 and live/dead staining showed no obvious cytotoxicity at HAMA@POSS-DS, and POSS-DS released by HAMA@POSS-DS significantly promoted cell proliferation (P<0.05). In the chondrocyte anti-inflammatory experiment, the relative expression of collagen type Ⅱ mRNA in HAMA@POSS-DS group was significantly higher than that in control group and blank group (P<0.05). The relative expression level of AGG mRNA was significantly higher than that of blank group (P<0.05). The relative expressions of MMP-13, Adamts5, and TAC1 mRNA in HAMA@POSS-DS group were significantly lower than those in blank group (P<0.05). In vivo experiments showed that the joint space width decreased after operation in rats with osteoarthritis, but HAMA@POSS-DS delayed the process of joint space narrowing and significantly improved the periarticular osteophytosis (P<0.05).

Conclusion

HAMA@POSS-DS can effectively regulate the local inflammatory microenvironment and significantly promote chondrocyte proliferation, which is conducive to promoting cartilage regeneration and repair in osteoarthritis.

Astaxanthin: A Marine Drug That Ameliorates Cerebrovascular-Damage-Associated Alzheimer's Disease in a Zebrafish Model via the Inhibition of Matrix Metalloprotease-13

Alzheimer's disease (AD) is a major type of dementia disorder. Common cognitive changes occur as a result of cerebrovascular damage (CVD) via the disruption of matrix metalloproteinase-13 (MMP-13). In diabetic cases, the progress of vascular dementia is faster and the AD rate is higher. Patients with type 2 diabetes are known to have a higher risk of the factor for AD progression. Hence, this study is designed to investigate the role of astaxanthin (AST) in CVD-associated AD in zebrafish via the inhibition of MMP-13 activity. CVD was developed through the intraperitoneal and intracerebral injection of streptozotocin (STZ). The AST (10 and 20 mg/L), donepezil (1 mg/L), and MMP-13 inhibitor (i.e., CL-82198; 10 μM) were exposed for 21 consecutive days in CVD animals. The cognitive changes in zebrafish were evaluated through light and dark chamber tests, a color recognition test, and a T-maze test. The biomarkers of AD pathology were assessed via the estimation of the cerebral extravasation of Evans blue, tissue nitrite, amyloid beta-peptide aggregation, MMP-13 activity, and acetylcholinesterase activity. The results revealed that exposure to AST leads to ameliorative behavioral and biochemical changes. Hence, AST can be used for the management of AD due to its multi-targeted actions, including MMP-13 inhibition.

The checkpoint inhibitor PD-1H/VISTA controls osteoclast-mediated multiple myeloma bone disease

Multiple myeloma bone disease is characterized by the development of osteolytic bone lesions. Recent work identified matrix metalloproteinase 13 as a myeloma-derived fusogen that induces osteoclast activation independent of its proteolytic activity. We now identify programmed death-1 homolog, PD-1H, as the bona fide MMP-13 receptor on osteoclasts. Silencing PD-1H or using Pd-1h^-/- bone marrow cells abrogates the MMP-13-enhanced osteoclast fusion and bone-resorptive activity. Further, PD-1H interacts with the actin cytoskeleton and plays a necessary role in supporting c-Src activation and sealing zone formation. The critical role of PD-1H in myeloma lytic bone lesions was confirmed using a Pd-1h^-/- myeloma bone disease mouse model wherein myeloma cells injected into Pd-1h^-/-Rag2^-/- results in attenuated bone destruction. Our findings identify a role of PD-1H in bone biology independent of its known immunoregulatory functions and suggest that targeting the MMP-13/PD-1H axis may represent a potential approach for the treatment of myeloma associated osteolysis.

In vitro and in vivo anti-osteoarthritis effects of tradition Chinese prescription Ji-Ming-San

ETHNOPHARMACOLOGICAL RELEVANCE

Ji-Ming-Shan (JMS) is a traditional herbal prescription consisting of seven herbs including Areca cathechu Burm.f., Citrus reticulata Blanco, Chaenomeles speciosa (Sweet) Nakai, Euodia ruticarpa (A. Juss.) Benth., Perilla frutescens (L.) Britton, Zingiber officinale Roscoe, Platycodon grandiflorus (Jacq.). It was first recorded during the Song dynasty and has been used extensively for protection against rheumatism, treatment of swelling of tendons, relief from foot pain, gout and diuresis and other forms of inflammation.

AIM OF THE STUDY

The aim of this study is to evaluate the anti-inflammatory and anti-osteoarthritis activity of JMS extracts with the use of different cell lines (RAW 264.7 cells, SW1353 cells and primary cultured rat chondrocytes). MIA-induced rat animal models were used to assess the anti-osteoarthritis activity of the extract.

MATERIALS AND METHODS

This study investigated the anti-inflammatory activity of JMS-95E on LPS-induced RAW 264.7 macrophages and IL-1β-stimulated chondrocytes. For the in vivo study, male Wistar rats were used and they were randomly assigned in different groups: blank, control, positive control and three different JMS-95E treatment groups (200, 400, 800 mg/kg/d). Paw edema, hind-limb weight bearing, serum inflammatory cytokines including hematoxylin and eosin (HE) staining experiments were used to assess the efficacy of the extract in the rat model.

RESULT

JMS 95% ethanol extract (JMS-95E, marker substance: narirutin (5.10 mg/g) and hesperidin (11.33 mg/g) has been identified in the extract using high pressure liquid chromatography. For in vitro assays, JMS-95E did not exhibit cytotoxicity and was able to downregulate the protein expression of iNOS, COX-2 and MMP-13. The production of inflammatory mediators such as NO and PGE₂ were also reduced with an increase in dose-dependent manner in various cell lines. Inhibitory activity on the key enzyme xanthine oxidase was also observed in this study. In rat animal models, JMS-95E reduced the inflammatory responses such as acute swelling, chondrocyte degradation and pain section of paw edema in rat model. Molecular marker studies of inflammation demonstrated that JMS-95E significantly decrease PGE₂ expression in MIA model.

CONCLUSION

JMS-95E inhibited the inflammatory pathway leading to the production or expression levels of NO, iNOS, COX-2 and PGE₂ in macrophage cells. In primary cultured rat chondrocytes iNOS and SW1353 MMP-13 expression were downregulated after JMS-95E treatment. For the in vivo study JMS-95E significantly reduced the paw volume of carrageenan-induced rat paw edema through each dose and significantly inhibited paw volume, counterweight the distribution of hind-paw weight bearing through the MIA model which means JMS-95E could promote recovery of the acute swelling and chondrocyte degradation of the ankle joints. The above results provided the multiple mechanism of JMS-95E in OA treatment of the scientific founding which supported the description of JMS in traditional use.

Profiling of Multiple Matrix Metalloproteinases Activities in the Progression of Osteosarcoma by Peptide Microarray-Based Fluorescence Assay on Polymer Brush-Coated Zinc Oxide Nanorod Substrate

Peptide microarray provides the ability to miniaturize, parallelize, and automate high-throughput screening substrate specificities of enzymes, profiling of multiple enzyme activities, discovery of disease biomarkers, and development of drugs. Matrix metalloproteinases (MMPs) are demonstrated as important biomarkers of tumor invasion and metastasis. Herein, a peptide microarray-based fluorescence assay is proposed to profile multiple MMPs (MMP-1, MMP-2, MMP-3, MMP-7, MMP-9, and MMP-13) activities in the culture medium of four human osteosarcoma (OS) cells and in the progression of OS by using the mouse-bearing xenograft OSs including U-2OS and Saos-2 human. This method has excellent selectivity and sensitivity, which enables to detect the activities of cellular secreted MMP-1, MMP-2, MMP-3, MMP-7, MMP-9, and MMP-13 with limit of detection downs to 10 pM, 30 pM, 113 pM, 13 pM, 93 pM, and 12 pM, respectively. Furthermore, it is demonstrated that the activity pattern of MMPs is serum closely relevant to the disease progression and type of tumor.

Peptide Array-Based In Situ Fluorescence Assay for Profiling Multiple Matrix Metalloproteinase Activities

Peptide array-based in situ fluorescence assay is a reliable and efficient technique for high-throughput profiling and localization of enzyme activity. Here, peptide array is fabricated by spotting five specific MMPs (MMP-2, MMP-3, MMP-7, MMP-9, and MMP-14) peptide substrates containing FAM/Dabcyl fluorescent resonance energy transfer (FRET) pair on the surface of cell monolayers or tissue sections. MMP activities are determined in situ by the fluorescence intensity of stained cells/tissues due to the cellular internalization of hydrolyzed peptide fragments with FAM moieties. Identification of MMP expression patterns of cells, highly sensitive determination of MMP activities in cell monolayer (as low as hundreds of cells per square centimeter), and evaluation of inhibition potencies of six compounds toward five MMPs are achieved by this method. Five MMP activities in the localized parts of 32 thyroid tissues are also well profiled without separation or extraction procedures.

Ershiwuwei Lvxue Pill alleviates rheumatoid arthritis by different pathways and produces changes in the gut microbiota

BACKGROUND

Rheumatoid arthritis (RA) is a systemic autoimmune disease that often results in joint destruction. Ershiwuwei Lvxue Pill (ELP), a prescription of Tibetan medicine, has been used for centuries for the clinical treatment of RA in Tibet, China. In a previous study, we reported that ELP could ameliorate RA symptoms in CIA rats by inhibiting the inflammatory response and inducing apoptosis in synovial tissues. It is still needed further to clarify the mechanisms of action of ELP in mitigating RA.

PURPOSE

In this study, we aim to elucidate the mechanism of action of ELP to improve RA joint damage and explore the changes in the intestinal flora and host metabolites.

METHODS

Firstly, we analyzed the main absorbed constituents of ELP in the serum of rats by ultra-performance liquid chromatography quadrupole-time-flight mass spectrometry (UPLC-Q-TOF/MS). Then, we verified the alleviating effects of ELP on cartilage injury and bone erosion as well as the inflammatory response in CIA rats by microCT, H&E staining, safranin-O staining, and ELISA. Moreover, we investigated the main factors that mediate joint damage, including the production of matrix metalloproteinases (MMPs) and osteoclast activity in the ankle of rats by immunohistochemistry and tartrate-resistant acid phosphatase (TRAP) staining. Further, we explored the molecular mechanisms of the MMPs production and osteoclast activity in CIA rats treated with ELP through various experiments such as ELISA, qRT-PCR, western blotting, and immunofluorescence assay. Besides, we investigated gut microbiota composition by 16S rDNA sequencing and serum metabolites through untargeted metabolomics. In addition, we analyzed the correlation between gut microbiota and metabolites by Spearman correlation analysis.

RESULTS

In this study, we identified 20 compounds from rat serum samples, which could be the ELP components that improve RA. Moreover, we found that ELP could alleviate cartilage and bone injury by reducing MMP-1, MMP-3, and MMP-13 expression and osteoclast activity in CIA rats. Further studies demonstrated that ELP could reduce joint damage by inhibiting osteoprotegerin (OPG)/receptor activator for nuclear factor-κB ligand (RANKL) /nuclear factor-κB (NF-κB) and extracellular signal-regulated kinase (ERK)/c-Jun N-terminal kinases (JNK) signal pathways. The 16S rDNA sequencing analysis indicated that there was a significant difference in the gut microbiota composition between the normal and CIA rats, and these differences were changed after ELP administration. ELP could alter the gut microbiota by increasing the abundance of the genus Lactobacillus and decreasing the abundance of Dorea, [Eubacterium]_ventriosum_group, Anaerostipes, Collinsella, Coprococcus_1, Ruminiclostridium_5, Ruminococcus_1, Family_XIII_UCG-001, Butyricicoccus, Erysipelotrichaceae_UCG-003, Lachnoclostridium, Faecalibacterium, Lachnospiraceae_UCG-010, Roseburia, Rs-E47_termite_group_norank, Treponema_2 genera. Non-targeted metabolomics analysis showed that ELP reduced arachidonic acid levels. The serum arachidonic acid level was significantly correlated with the abundance of 41 genera, particularly Collinsella and Lactobacillus.

CONCLUSION

Our study shows that ELP can improve RA joint damage by inhibiting MMPs production and osteoclast activity, and regulating intestinal flora and host metabolites, which provides a novel insight into the ELP in alleviating RA.

Rongjin Niantong Fang ameliorates cartilage degeneration by regulating the SDF-1/CXCR4-p38MAPK signalling pathway

CONTEXT

Rongjin Niantong Fang (RJNTF) is a Traditional Chinese Medicine formulation with a good therapeutic effect on osteoarthritis (OA). However, the underlying mechanisms remain unclear.

OBJECTIVE

This study investigates whether RJNTF could delay OA cartilage degeneration by regulating the SDF-1/CXCR4-p38MAPK signalling pathway.

MATERIALS AND METHODS

The Sprague-Dawley (SD) rats were used to establish the OA model by a modified Hulth's method. SD rats were divided into three groups (n = 10): blank group, model group (0.9% saline, 10 mL/kg/day), and treatment group (RJNTF, 4.5 g/kg/day). After 12 weeks of treatment, each group was analysed by H&E, Safranine-O solid green, ELISA, Immunohistochemistry, and Western blot. An in vitro model was induced with 100 ng/mL SDF-1 by ELISA, the blank group, model group, RJNTF group, and inhibitor group with intervention for 12 h, each group was analysed by Immunofluorescence staining and Western blot.

RESULTS

SDF-1 content in the synovium was reduced in RJNTF treatment group compared to non-treatment model group (788.10 vs. 867.32 pg/mL) and down-regulation of CXCR4, MMP-3, MMP-9, MMP-13 protein expression, along with p38 protein phosphorylated were observed in RJNTF treatment group. In vitro results showed that RJNTF (IC₅₀ = 8.925 mg/mL) intervention could down-regulate SDF-1 induced CXCR4 and p38 protein phosphorylated and reduce the synthesis of MMP-3, MMP-9, and MMP-13 proteins of chondrocytes from SD rat cartilage tissues.

DISCUSSION AND CONCLUSION

RJNTF alleviates OA cartilage damage by SDF-1/CXCR4-p38MAPK signalling pathway inhibition. Our ongoing research focuses on Whether RJNTF treats OA through alternative pathways.

Discovery of Phenolic Matrix Metalloproteinase Inhibitors by Peptide Microarray for Osteosarcoma Treatment

Because of the abnormal upregulation of matrix metalloproteinase (MMP) activities in tumors, MMP inhibitors (MMPIs) are validated anticancer drug candidates. We identified several MMPIs including mangiferin as an MMP-9 inhibitor with a half maximal inhibitory concentration (IC₅₀) value of 250 nM, isosilybin as an MMP-13 inhibitor with an IC₅₀ value of 250 nM, and isoliquiritigenin as a broad-spectrum MMPI (with IC₅₀ values of 16 nM for MMP-1, 10 nM for MMP-2, 81 nM for MMP-3, 8 nM for MMP-7, 10 nM for MMP-9, and 14 nM for MMP-13) through studying the interactions of 6 MMPs secreted by U-2OS cells with 51 phenolic natural products on the peptide microarray platform. In addition, the inhibitory mechanisms of as-discovered MMPIs were evaluated by a molecular docking simulation. The antitumor efficiencies of MMPIs were demonstrated by both a cell scratch test and growth suppression of mouse-born OS tumors. The results of the cell scratch test suggested that isoliquiritigenin significantly inhibited the migration of U-2OS cells. In addition, administration of isoliquiritigenin significantly reduced the tumor size (by about 80%) and prolonged the survival time (by more than 70 days). This study suggests that the discovery of MMPIs from phenolic natural products is a meaningful way to screen anticancer agents.

Risk Factors for Pulmonary Metastasis in Differentiated Thyroid Carcinoma Patients and the Significance of Changes in Matrix Metalloproteinase 13 and microRNA-142 Levels

This work aims to explore the risk factors of lung metastasis (LM) in differentiated thyroid cancer (DTC) (LM-DTC) and the effect of treatment and to detect the relationship between LM-DTC and the levels of matrix metalloproteinase-13 (MMP-13) and micro ribonucleic acid (RNA)-142 (miR-142) in peripheral blood. The data of 420 patients with DTC who are admitted from March 2020 to December 2021 are collected and divided into a non-metastasis group (non-LM group) of 400 cases and metastasis group (LM group) of 20 cases according whether the mung metastasis is found. In addition, risk factors of LM-DTC are analysed and compared. The results of multivariate logistic analysis show that age, disease course, and imaging timing are independent influencing factors of the radionuclide treatment effect. Follicular carcinoma, abnormal expressions of MMP-13, and miR-142 can increase the risk of LM-DTC. MMP-13 and miR-142 can be undertaken as auxiliary diagnostic biological indicators.

Gastrocnemius Muscle Injury Is the Condition to Induce Cartilage Degeneration of the Rabbit Tibiofemoral Joint: A New Perspective

The knee osteoarthritis is a common joint disease that causes pain and inconvenience. Clinically, patients with knee osteoarthritis often have response points on the gastrocnemius. Gastrocnemius plays an essential role in stabilizing joints and changing gait and pace, which also has a close relationship with the knee joint. The objective of this study is to determine changes in the tibiofemoral joint after medial and lateral gastrocnemius injury. Rabbits were divided into a medial gastrocnemius injury group, a lateral gastrocnemius injury group, and a control group with two intervals: 6 and 8 weeks after modeling of the semisevered gastrocnemius. The gastrocnemius was weighed and sectioned for histology. The joint space and subchondral bone were observed using X-ray and microcomputed tomography. The cartilage was observed histologically using Safranin O fast green and Masson and immunohistochemically using antibodies to collagen type II, matrix metalloproteinase 13, and integrin beta1. Results showed muscle fiber atrophy, and fibrotic changes occurred after gastrocnemius semidissociation. After gastrocnemius injury, the femoral condyle of the tibiofemoral joint produced abnormal sclerosis and bone degeneration. The pathological changes of cartilage included disordered or reduced cell alignment, cartilage matrix loss, and collagen loss due to decreased collagen type II and increased matrix metalloproteinase 13 activity. The increase of integrin beta1 in the injured group may be related to mechanical conduction process. The results suggest that gastrocnemius injury is an essential factor in tibiofemoral arthritis.

WISP-2 modulates the induction of inflammatory mediators and cartilage catabolism in chondrocytes

Wnt-1 inducible signaling pathway protein 2 (WISP-2/CCN5) is a recently identified adipokine that has been described as an important mediator of canonical Wnt activation in adipogenic precursor cells. In osteoarthritis (OA), the most common form of arthritis, chondrocytes exhibit aberrant and increased production of pro-inflammatory mediators and matrix degrading enzymes such as IL-1β and MMP-13. Although recent evidence suggests a role for Wnt signaling in OA physiopathology, little is known about the involvement of WISP-2 in cartilage degradation. In the present study, we determined the expression of WISP-2 in healthy and OA human chondrocytes. WISP-2 expression is modulated along chondrocyte differentiation and downregulated at the onset of hypertrophy by inflammatory mediators. We also investigated the effect of WISP-2 on cartilage catabolism and performed WISP-2 loss-of-function experiments using RNA interference technology in human T/C-28a2 immortalized chondrocytes. We demonstrated that recombinant human WISP-2 protein reduced IL-1β-mediated chondrocyte catabolism, that IL-1β and WNT/b-catenin signaling pathways are involved in rhWISP-2 protein and IL-1β effects in human chondrocytes, and that WISP-2 has a regulatory role in attenuating the catabolic effects of IL-1β in chondrocytes. Gene silencing of WISP-2 increased the induction of the catabolic markers MMP-13 and ADAMTS-5 and the inflammatory mediators IL-6 and IL-8 triggered by IL-1β in human primary OA chondrocytes in a Wnt/β-catenin dependent manner. In conclusion, here we have shown for the first time that WISP-2 may have relevant roles in modulating the turnover of extracellular matrix in the cartilage and that its downregulation may detrimentally alter the inflammatory environment in OA cartilage. We also proved the participation of Wnt/β-catenin signaling pathway in these processes. Thus, targeting WISP-2 might represent a potential therapeutical approach for degenerative and/or inflammatory diseases of musculoskeletal system, such as osteoarthritis.

Lin28a induces SOX9 and chondrocyte reprogramming via HMGA2 and blunts cartilage loss in mice

Articular cartilage has low regenerative capacity despite permanent stress. Irreversible cartilage lesions characterize osteoarthritis (OA); this is not followed by tissue repair. Lin28a, an RNA binding protein, is detected in damaged cartilage in humans and mice. We investigated the role of LIN28a in cartilage physiology and in osteoarthritis. Lin28a-inducible conditional cartilage deletion up-regulated Mmp13 in intact mice and exacerbated the cartilage destruction in OA mice. Lin28a-specific cartilage overexpression protected mice against cartilage breakdown, stimulated chondrocyte proliferation and the expression of Prg4 and Sox9, and down-regulated Mmp13. Lin28a overexpression inhibited Let-7b and Let-7c miRNA levels while RNA-sequencing analysis revealed five genes of transcriptional factors regulated by Let-7. Moreover, Lin28a overexpression up-regulated HMGA2 and activated SOX9 transcription, a factor required for chondrocyte reprogramming. HMGA2 siRNA knockdown inhibited the cartilage protective effect of Lin28a overexpression. This study provides insights into a new pathway including the Lin28a-Let7 axis, thus promoting chondrocyte anabolism in injured cartilage in mice.

Pre-Clinical Study: Immunohistochemical evaluation of matrix metalloproteinase-13 on rabbit (Oryctolagus cuniculus) socket healing after application of platelet-rich fibrin with and without hydroxyapatite

Background: Tissue engineering technology has been used globally and proven to accelerate wound healing. This study aimed to analyse the effect of adding hydroxyapatite (HA) as a scaffold to platelet-rich fibrin (PRF) as a growth factor in accelerating the wound healing process as seen from the expression of matrix metalloproteinase-13 (MMP-13). Methods: This research is an animal experiment conducted on 18 rabbits (Oryctolagus cuniculus). Rabbits were randomly divided into the following three groups of treatment: (G1) the application of PRF group, (G2) the application of PRF+HA group and (C) the control group without any application. Furthermore, each treatment group was split randomly into three groups of observation time. Periodontal tissue biopsy was performed to analyse the histopathological features that were examined on the basis of the level of MMP-13 immunoexpression. Results: MMP-13 immunoexpression in the PRF+HA group showed better histoscore results, indicating a substantial reduction in MMP-13 values compared with other groups. The healing process was shown to increase with increasing observation time (p<0.05), and the PRF+HA group outperformed the PRF and control groups. On day 3, MMP-13 exhibited a dark brown colour of Immunohistochemistry (IHC), which indicated an increase in the expression value of MMP-13 in the early stages of healing, namely, inflammation. On day 14, light brown IHC was seen, especially in group 2, as a reference that the remodeling process had begun. Conclusions: This study indicates that the administration of PRF and HA was capable of reducing the MMP-13 expression that significantly accelerates the socket healing process. Hydroxyapatite is an alloplastic material that has inherent bioactive properties that support osteoconduction, can bind MMPs, and showed faster healing results based on the observation time as documented by immunohistochemistry.

Acute Physiological Effects of Continuous Versus Intermittent Walking During Golf in Individuals With Knee Osteoarthritis: A Pilot Study

OBJECTIVE

The aim of the study was to compare the acute effects of walking the golf course versus using a golf cart during a round of golf on biological markers of joint disease, joint pain, and cardiovascular parameters in individuals with knee osteoarthritis.

METHODS

Participants with knee OA (n = 10) older than 50 yrs were recruited for this crossover designed study in which they completed two 18-hole rounds of golf: (1) walking the course and (2) using a golf cart. Five control participants (n = 5) performed the walking condition only. Step count, heart rate, rating of perceived exertion and pain using the Numeric Pain Rating Scale were measured during the round. Serum was collected at baseline, 9th hole (halfway), and 18th hole (completion) and tested for biomarkers associated with tissue turnover (cartilage oligomeric matrix protein), inflammation (tumor necrosis factor α, interleukin 1β, interleukin 6), and degradative enzyme production (matrix metalloproteinase 3, matrix metalloproteinase 13).

RESULTS

In knee OA participants, walking the course was associated with significantly higher step count and duration of moderate/vigorous physical activity (72.2% vs. 32.6% of the round) but did lead to a significant increase in knee joint pain (P < 0.05). Both conditions caused cartilage oligomeric matrix protein and matrix metalloproteinase 13 concentration increases from baseline to completion (P < 0.05), but inflammatory markers (tumor necrosis factor α, interleukin 6, and interleukin 1β, P < 0.05) only increased when walking the course. Biomarker concentrations did not increase in control participants.

CONCLUSIONS

Walking the course optimizes the duration of moderate/vigorous activity during a round of golf, but the golf cart is a beneficial option in those with exacerbated joint pain and inflammation that would otherwise limit participation.

[Mechanism of microRNA-100-5p on mammalian target of rapamycin in temporomandibular arthritis]

PURPOSE

To investigate the mechanism of microRNA-100-5p (miR-100-5p) on mammalian target (mTOR) of rapamycin in temporomandibular arthritis.

METHODS

Sixty SD rats were randomly divided into group A, group B, group C, group D, and group E, with 12 rats in each group. Rat models of temporomandibular arthritis were prepared by injecting sodium iodoacetate solution into the bilateral spaces of temporomandibular joint. After establishment, group C was injected pcDNA3.1-miR-100-5p recombinant plasmid, group D was injected mTOR inhibitor rapamycin, group E was injected with pcDNA3.1-miR-100-5p recombinant plasmid and rapamycin, and group A was injected same amount of normal saline in the same way. Various indexes were observed in each group, including morphological changes of temporomandibular joint tissues, matrix metalloproteinase-3 (MMP-3), MMP-1, MMP-13, interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), miR-100-5p, mTOR expression. The data were processed using SPSS 22.0 software package.

RESULTS

In group B, the structure of temporomandibular joint was fuzzy, with synovial hyperplasia, vascular dilatation, clustered cells and a large amount of inflammatory infiltration. Histopathological changes of temporomandibular joint in each interventional group were improved to different degrees compared with group B, among which group E showed the most obvious improvement. The levels of MMP-3, MMP-1, MMP-13, IL-6, IL-1β and TNF-α in group B were significantly higher than those in group A(P＜0.05). The levels of MMP-3, MMP-1, MMP-13, IL-6, IL-1β and TNF-α in group C, group D and group E were significantly lower than those in group B(P＜0.05). The levels of MMP-3, MMP-1, MMP-13, IL-6, IL-1β and TNF-α in group D were not significantly different from those in group C (P＜0.05). The levels of MMP-3, MMP-1, MMP-13, IL-6, IL-1β and TNF-α in group E were significantly lower than those in group D (P＜0.05). The expression level of miR-100-5p in group E was significantly higher than that in group B (P＜0.05). The expression level of mTOR protein in group E was significantly lower than that in group B (P＜0.05).

CONCLUSIONS

MicroRNA-100-5p may alleviate temporomandibular arthritis by down-regulating the expression of mTOR.

miR-125a-5p-abundant exosomes derived from mesenchymal stem cells suppress chondrocyte degeneration via targeting E2F2 in traumatic osteoarthritis

miRNAs are broad participants in vertebrate biological processes, and they are also the major players in pathological processes. miR-125a-5p was recently found a modulator in the progression of osteoarthritis (OA). Our study was aimed to explore the role and underlying mechanisms of miR-125a-5p-abundant exosomes derived from mesenchymal stem cells (MSC) on OA progression. We separated bone marrow mesenchymal stem cells (BMSCs) as well as the exosomes from traumatic OA patients. The immunofluorescence and cartilage staining were implemented for the observation and the assessment on endocytosis of chondrocytes and exosomal miR-125a-5p efficacy to cartilage degradation. Dual luciferase reporter assay was performed to verified the relationship between miR-125a-5p and E2F2. Then, the function of exosomal miR-125a-5p were examined on chondrocyte degeneration in vitro and in vivo. Our findings indicated that E2F2 expression was elevated while the miR-125a-5p was down in traumatic OA cartilage tissue, showing a negative correlation of the former and the latter. miR-125a-5p targets E2F2 in traumatic OA cartilage tissue and leads to the down-expression of E2F2. The E2F2 expression in chondrocytes was decreased after internalization of exosomes. We additionally found that BMSCs-derived exosomes were rich in miR-125a-5p content and chondrocytes can have it internalized. miR-125a-5p is endowed with a trait of accelerating chondrocytes migration, which is going along with the up-expressions of Collagen II, aggrecan and SOX9 and the down-expression of MMP-13 in vitro. Besides that, the mice model with post-traumatic OA turned out that exosomal miR-125a-5p might beget an alleviation in chondrocyte extracellular matrix degradation. All these outcomes revealed that BMSCs-derived exosomal miR-125a-5p is a positive regulator for chondrocyte migration and inhibit cartilage degeneration We thus were reasonable to believe that transferring of exosomal miR-125a-5p is a prospective strategy for OA treatment.

The potential value of diagnostic and predictive serum biomarkers for preeclampsia

BACKGROUND

Preeclampsia (PE), one of the classes of hypertensive pregnancy disorders, is one of the three causes of maternal morbidity and mortality worldwide. The angiogenic and anti-angiogenic factors are useful markers in predicting and diagnosing PE.

AIM

This study aims to detect and measure the serum level of some biomarkers [hypoxia-inducible factor-1 subunit alpha (HIF-1A), vascular endothelial growth factor (VEGF), interferon-gamma-inducible protein of 10 kDa (IP-10), matrix metalloproteinase-13 (MMP-13)] in patients with PE and their correlation with the severity of the disease, to find a good predictor for PE.

PATIENTS, MATERIALS AND METHODS

This prospective study aims to monitor 48 pregnant women who address obstetric consultation and who present risk factors for PE, and a control group with characteristics similar to the study group. Patients were divided into three groups: Group I (n=15) including normal pregnant (NP) women with blood pressure <140∕90 mmHg, without proteinuria, Group II (n=18) including patients with mild PE (MildPE), Group III (n=15) including patients with severe PE (SeverePE). The analysis of serum biomarkers was based on a quantitative sandwich enzyme-linked immunosorbent assay (ELISA), according to the manufacturer's instructions.

RESULTS

In our study, we found that all biomarkers investigated have higher concentrations in the serum of patients with SeverePE and MildPE than those in the control subjects (Group I, NP), the concentrations were increasing along with the disease activity. The means concentrations of HIF-1A, VEGF, IP-10, MMP-13, better correlated with indices in SeverePE group than in MildPE group. We found that VEGF was the biomarker that best correlates with indices that assess the severity of PE. The best separation of patients with SeverePE from those with MildPE can be done with the help of MMP-13 (82% accuracy), followed by VEGF (80.40% accuracy) and the least good detection being done by dosing IP-10.

CONCLUSIONS

We can say that, due to high specificity diagnostic accuracy, determination of serum concentrations of MMP-13 and VEGF, could be useful in the diagnosis and distinguishing of patients with SeverePE and may prove useful in the monitoring of the disease course.

Targeting Dysregulation of Metalloproteinase Activity in Osteoarthritis

Metalloproteinases were first identified as collagen cleaving enzymes and are now appreciated to play important roles in a wide variety of biological processes. The aberrant activity and dysregulation of the metalloproteinase family are linked to numerous diseases including cardiovascular and pulmonary diseases, chronic wounds, cancer, fibrosis and arthritis. Osteoarthritis (OA) is the most prevalent age-related joint disorder that causes pain and disability, but there are no disease-modifying drugs available. The hallmark of OA is loss of articular cartilage and elevated activities of matrix-degrading metalloproteinases are responsible. These enzymes do not exist in isolation and their activity is tightly regulated by a number of processes, such as transcription, proteolytic activation, interaction with their inhibitors, cell surface and extracellular matrix molecules, and endocytic clearance from the extracellular milieu. Here, we describe the functions and roles of metalloproteinase family in OA pathogenesis. We highlight recent studies that have illustrated novel mechanisms regulating their extracellular activity and impairment of such regulations that lead to the development of OA. We also discuss how to stop or slow down the degenerative processes by targeting aberrant metalloproteinase activity, which may in future become therapeutic interventions for the disease.

miR‑654‑5p inhibits autophagy by targeting ATG7 via mTOR signaling in intervertebral disc degeneration

Intervertebral disc degeneration (IDD) is a common chronic disease characterized by the loss of extracellular matrix (ECM) in the nucleus pulposus (NP). Accumulating evidence has revealed that abnormal expression of microRNAs (miRs) is closely associated with IDD development. The present study aimed to investigate the precise role and possible mechanism underlying the effects of miR‑654‑5p in the pathogenesis of IDD. NP cells were isolated from patients with IDD. Monodansylcadaverine staining was conducted to reveal cell autophagy, while western blotting was performed to detect the expression of ECM‑related proteins in NP cells. Luciferase reporter and RNA immunoprecipitation assays were conducted to identify the binding between RNAs. The results demonstrated that miR‑654‑5p was significantly upregulated in degenerated NP tissues from patients with IDD and high miR‑654‑5p expression was positively associated with disc degeneration grade. Functional assays suggested that miR‑654‑5p facilitated ECM degradation by increasing the expression levels of MMP‑3, MMP‑9 and MMP‑13, as well as decreasing collagen I, collagen II, SOX9 and aggrecan expression by inhibiting autophagy. Furthermore, autophagy‑related gene 7 (ATG7) was verified as a direct downstream target gene of miR‑654‑5p. miR‑654‑5p could bind to the 3' untranslated region of ATG7 to inhibit its mRNA expression and further reduce its translation. Notably, ATG7 knockdown abrogated the effects of the miR‑654‑5p inhibitor on ECM degradation and autophagy regulation. Furthermore, miR‑654‑5p inhibited autophagy in NP cells by increasing the protein expression levels of phosphorylated (p)‑PI3K, p‑AKT and p‑mTOR in an ATG7‑dependent manner. In conclusion, the results of the present study revealed that miR‑654‑5p may enhance ECM degradation via inhibition of autophagy by targeting ATG7 to activate the PI3K/AKT/mTOR signaling pathway. These findings may provide novel insights into the treatment of IDD.

Matrix Metalloproteinase 13 Inhibitors for Modulation of Osteoclastogenesis: Enhancement of Solubility and Stability

Matrix metalloproteinase 13 (MMP-13) activity has been correlated to breast cancer bone metastasis. It has been proposed that MMP-13 contributes to bone metastasis through the promotion of osteoclastogenesis. To explore the mechanisms of MMP-13 action, we previously described a highly efficacious and selective MMP-13 inhibitor, RF036. Unfortunately, further pursuit of RF036 as a probe of MMP-13 in vitro and in vivo activities was not practical due to the limited solubility and stability of the inhibitor. Our new study has explored replacing the RF036 backbone sulfur atom and terminal methyl group to create inhibitors with more favorable pharmacokinetic properties. One compound, designated inhibitor 3, in which the backbone sulfur and terminal methyl group of RF036 were replaced by nitrogen and oxetane, respectively, had comparable activity, selectivity, and membrane permeability to RF036, while exhibiting greatly enhanced solubility and stability. Inhibitor 3 effectively inhibited MMP-13-mediated osteoclastogenesis but spared collagenolysis, and thus represents a next-generation MMP-13 probe applicable for in vivo studies of breast cancer metastasis.

WNT16 is upregulated early in mouse TMJ osteoarthritis and protects fibrochondrocytes against IL-1β induced inflammatory response by regulation of RUNX2/MMP13 cascade

WNT16 has been shown to play important roles in joint formation, bone homeostasis and knee joint osteoarthritis. However, whether WNT16 has any effect during temporomandibular joint osteoarthritis (TMJOA) is still unknown. Here, we first established a surgically induced TMJOA model by performing partial discectomy in discs of TMJ in mice. Further, we investigated the role of WNT16 during the initiation and progression of TMJOA. Our results showed that WNT16 expression is upregulated early at 4 weeks after initiation of osteoarthritis by partial discectomy in mouse TMJ cartilage, but decreased after 12 weeks post-surgery. Further cellular and molecular analyses revealed that WNT16 signals via both the canonical WNT/β-catenin and non-canonical WNT/JNK-cJUN pathways, upregulates the expression of Lubricin and SOX9, and protects against IL-1β induced inflammatory response by regulation of RUNX2/MMP13 cascade in fibrochondrocytes. In conclusion, WNT16 may play an important role in the early stage of TMJOA by regulating cartilage anabolic and catabolic factors, and may serve as novel therapeutic targets for TMJOA.

Nuclear Stiffness Decreases with Disruption of the Extracellular Matrix in Living Tissues

Reciprocal interactions between the cell nucleus and the extracellular matrix lead to macroscale tissue phenotype changes. However, little is known about how the extracellular matrix environment affects gene expression and cellular phenotype in the native tissue environment. Here, it is hypothesized that enzymatic disruption of the tissue matrix results in a softer tissue, affecting the stiffness of embedded cell and nuclear structures. The aim is to directly measure nuclear mechanics without perturbing the native tissue structure to better understand nuclear interplay with the cell and tissue microenvironments. To accomplish this, an atomic force microscopy needle-tip probe technique that probes nuclear stiffness in cultured cells to measure the nuclear envelope and cell membrane stiffness within native tissue is expanded. This technique is validated by imaging needle penetration and subsequent repair of the plasma and nuclear membranes of HeLa cells stably expressing the membrane repair protein CHMP4B-GFP. In the native tissue environment ex vivo, it is found that while enzymatic degradation of viable cartilage tissues with collagenase 3 (MMP-13) and aggrecanase-1 (ADAMTS-4) decreased tissue matrix stiffness, cell and nuclear membrane stiffness is also decreased. Finally, the capability for cell and nucleus elastography using the AFM needle-tip technique is demonstrated. These results demonstrate disruption of the native tissue environment that propagates to the plasma membrane and interior nuclear envelope structures of viable cells.

Molecular docking study of flavonoid compounds for possible matrix metalloproteinase-13 inhibition

OBJECTIVES

Matrix metalloproteinase-13 (MMP-13) has been reported to be involved in different biological processes such as degradation of extracellular matrix proteins, activating or degrading some significant regulatory proteins, wound healing, tissue remodeling, cartilage degradation, bone development, bone mineralization, ossification, cell migration, and tumor cell invasion. Further, MMP-13 participates in many oral diseases such as tooth decay, gingivitis, and degradation of enamel and tissue around the implant. In addition, inhibition of MMP-13 has shown therapeutic properties for Alzheimer's disease (AD). We performed molecular docking to assess the binding affinity of 29 flavonoid compounds with the MMP-13. Additionally, pharmacokinetic and toxicity characteristics of the top-ranked flavonoids were studied. The current study also intended to identify the most important amino acids involved in the inhibition of MMP-13 based on topological feature (degree) in the ligand-amino acid network for MMP-13.

METHODS

Molecular docking and network analysis were studied using AutoDock and Cytoscape software, respectively. Pharmacokinetic and toxicity characteristics of compounds were predicted using bioinformatics web tools.

RESULTS

The results revealed that nine of the studied flavonoids had considerable estimated free energy of binding and inhibition constant: Rutin, nicotiflorin, orientin, vitexin, apigenin-7-glucoside, quercitrin, isoquercitrin, quercitrin-3-rhamnoside, and vicenin-2. Proline-242 was found to be the most important amino acid inhibiting the enzyme.

CONCLUSIONS

The results of the current study may be helpful in the prevention and therapeutic procedures of many disorders such as cancer, tooth caries, and AD. Nevertheless, validation tests are required in the future.

Cleavage by MMP-13 renders VWF unable to bind to collagen but increases its platelet reactivity

BACKGROUND

Atherosclerotic plaque rupture and subsequent thrombosis underpin thrombotic syndromes. Under inflammatory conditions in the unstable plaque, perturbed endothelial cells secrete von Willebrand Factor (VWF) which, via its interaction with GpIbα, enables platelet rolling across and adherence to the damaged endothelium. Following plaque rupture, VWF and platelets are exposed to subendothelial collagen, which supports stable platelet adhesion, activation, and aggregation. Plaque-derived matrix metalloproteinase (MMP)-13 is also released into the surrounding lumen where it may interact with VWF, collagen, and platelets.

OBJECTIVES

We sought to discover whether MMP-13 can cleave VWF and whether this might regulate its interaction with both collagen and platelets.

METHODS

We have used platelet adhesion assays and whole blood flow experiments to assess the effects of VWF cleavage by MMP-13 on platelet adhesion and thrombus formation.

RESULTS

Unlike the shear-dependent cleavage of VWF by a disintegrin and metalloprotease with thrombospondin motif member 13 (ADAMTS13), MMP-13 is able to cleave VWF under static conditions. Following cleavage by MMP-13, immobilized VWF cannot bind to collagen but interacts more strongly with platelets, supporting slower platelet rolling in whole blood under shear. Compared with intact VWF, the interaction of cleaved VWF with platelets results in greater GpIbα upregulation and P-selectin expression, and the thrombi formed on cleaved VWF-collagen co-coatings are larger and more contractile than platelet aggregates on intact VWF-collagen co-coatings or on collagen alone.

CONCLUSIONS

Our data suggest a VWF-mediated role for MMP-13 in the recruitment of platelets to the site of vascular injury and may provide new insights into the association of MMP-13 in atherothrombotic and stroke pathologies.

Investigation of the efficacy of daidzein in experimental knee osteoarthritis-induced with monosodium iodoacetate in rats

BACKGROUND

Osteoarthritis (OA) is a degenerative chronic illness that most frequently occurs in the knee joint. Daidzein (DZ) an isoflavone has anti-inflammatory and antioxidant activity. The aim of this study was to evaluate the effectiveness of DZ as a treatment for experimental knee OA (KOA) in rats.

METHOD

An experimental KOA model was induced by monosodium iodoacetate (MIA) in rats. Thereafter, 49 Wistar albino male rats (250-300 g, 12-16 weeks old) were randomly divided into 7 groups: C (healthy control); DC (KOA + saline); hyaluronic acid (HA); HA+ intraarticular (ia) DZ; oral (po) DZ; ia DZ; HA + po DZ groups. DZ and/or HA were administered intraarticularly to the rats as 50 μL on days 1, 7, 14, and 21. Alternatively, the DZ was administered orally as 0.5 mL twice daily for 21 days. After the treatment, rats were sacrificed by decapitation under general anesthesia. Serum samples were analyzed to determine the total oxidant status (TOS) and total antioxidant status (TAS) and the levels of TNF-α, IL-1β, MMP-13, and DZ. Knee joint samples underwent histopathological examination, and TNF-α, IL-1β, NOS2, and MMP-13 were analyzed with immunohistochemical methods.

RESULTS

HA, DZ, and DZ + HA effectively reduced the levels of TNF-α, IL-1β, and MMP-13 in the serum of the DC group (p < 0.001). In groups that received HA, DZ, or DZ + HA, the serum TAS increased compared with the DC group (p < 0.05). When the DZ + HA combination was used, a more pronounced reduction in the levels of TNFα, NOS2, IL-1β, and MMP-13 was observed in knee joints. In addition, the cracks on the cartilage surface and fibrillation were completely improved in the groups that received HA, DZ, or DZ + HA compared with the DC group.

CONCLUSION

DZ had anti-inflammatory and antioxidant effects in a rat OA model. Therefore, DZ, as monotherapy or especially in combination with HA, may be a promising and beneficial therapy for OA. Key Points •DZ has been shown to reduce TNF-α, IL-1β, and MMP-13 both in serum and in tissue samples taken from the knee-joints. •The cracks on the cartilage surface and fibrillation in KOA were completely improved by using DZ and DZ + HA combination. •DZ may be useful to eliminate/reduce/ameliorate inflammation and oxidative damage in the pathogenesis of KOA. •DZ, alone or in combination with HA, may be a promising natural compound with beneficial effects in the treatment of KOA.

Dexmedetomidine inhibits the NF-κB pathway and NLRP3 inflammasome to attenuate papain-induced osteoarthritis in rats

Context: Dexmedetomidine (Dex) has been reported to have an anti-inflammatory effect. However, its role on osteoarthritis (OA) has not been explored. Objective: This study investigates the effect of Dex on OA rat model induced by papain. Materials and methods: The OA Wistar rat model was induced by intraluminal injection of 20 mL of papain mixed solution (4% papain 0.2 mL mixed with 0.03 mol L^-1 l-cysteine 0.1 mL) into the right knee joint. Two weeks after papain injection, OA rats were treated by intra-articular injection of Dex (5, 10, or 20 μg kg^-1) into the right knee (once a day, continuously for 4 weeks). Articular cartilage tissue was obtained after Dex treatment was completed. Results: The gait behavior scores (2.83 ± 0.49), PWMT (15.2 ± 1.78) and PTWL (14.81 ± 0.92) in H-DEX group were higher than that of OA group, while Mankin score (5.5 ± 0.81) was decreased (p < 0.05). Compared with the OA group, the IL-1β (153.11 ± 16.05 pg mg^-1), IL-18 (3.71 ± 0.7 pg mg^-1), IL-6 (14.15 ± 1.94 pg/mg) and TNF-α (40.45 ± 10.28 pg mg^-1) levels in H-DEX group were decreased (p < 0.05). MMP-13, NLRP3, and caspase-1 p10 expression in Dex groups were significantly lower than that of OA group (p < 0.05), while collagen II was increased (p < 0.05). p65 in the nucleus of Dex groups was significantly down-regulated than that of OA group (p < 0.05). Discussion and Conclusions: Dex can improve pain symptoms and cartilage tissue damage of OA rats, which may be related to its inhibition of the activation of NF-κB and NLRP3 inflammasome.

Novel Pituitary Actions of Epidermal Growth Factor: Receptor Specificity and Signal Transduction for UTS1, EGR1, and MMP13 Regulation by EGF

Epidermal growth factor (EGF) is a member of the EGF-like ligands family, which plays a vital role in cell proliferation, differentiation, and folliculogenesis through binding with EGF receptors, including ErbB1 (EGFR/HER1), ErbB2 (HER2), ErbB3 (HER3), and ErbB4 (HER4). In mammals, many functional roles of EGF have been reported in the ovaries and breasts. However, little is known about the functions of EGF in the pituitary, especially in teleost. In this study, using grass carp pituitary cells as the model, we try to examine the direct pituitary actions of EGF in teleost. Firstly, transcriptomic analysis showed that 599 different expressed genes (DEGs) between the control and EGF-treatment group were mainly involved in cell proliferation, cell migration, signal transduction, and transcriptional regulation. Then, we further confirmed that EGF could significantly induce UTS1, EGR1, and MMP13 mRNA expression in a time-and dose-dependent manner. The stimulatory actions of EGF on UTS1 and EGR1 mRNA expression were mediated by the MEK_1/2/ERK_1/2 and PI₃K/AKT/mTOR pathways coupled with both ErbB1 and ErbB2 in grass carp pituitary cells. The receptor specificity and signal transductions for the corresponding responses on MMP13 mRNA expression were also similar, except that the ErbB2 and PI₃K/AKT/mTOR pathway were not involved. As we know, MMP13 could release EGF from HB-EGF. Interestingly, our data also showed that the MMPs inhibitor BB94 could suppress EGF-induced UTS1 and EGR1 mRNA expression. These results, taken together, suggest that the stimulatory actions of EGF on UTS1 and EGR1 mRNA expression could be enhanced by EGF-induced MMP13 expression in the pituitary.

Effects of Tumor Necrosis Factor Inhibitor on Stress-Shielded Tendons

Mechanical stress plays an important role in preserving the integrity of bone and ligament. Stress shielding reduces mechanical load on bone or tendons, resulting in tissue degradation. Previous studies showed that deterioration of the tendon structure during stress shielding is associated with elevated expression of tumor necrosis factor (TNF)-α. This study examined the therapeutic potential of the TNF inhibitor etanercept in preventing morphologic deterioration of the Achilles tendon after stress shielding. Rats (N=48) were exposed to stress shielding of the left Achilles tendon and treated with etanercept or phosphate-buffered saline for 2 or 4 weeks. The right Achilles tendons were used as controls. After 2 or 4 weeks, stress-shielded tendons appeared less smooth than control tendons, and the stress-shielded tendons formed adhesions with surrounding tissues. Transmission electron microscopy also showed disarray of the collagen fibrils and a significant increase in the number of small-diameter collagen fibrils. These changes were associated with increased expression of TNF-α, matrix metalloproteinase (MMP)-13, MMP-3, collagen I, and collagen III. Treatment with 2 weeks of etanercept injection reduced morphologic changes in collagen organization and structure induced by stress shielding. Etanercept treatment also attenuated upregulation of MMP-13, MMP-3, and collagen III levels. However, no significant difference was observed between the etanercept group and the phosphate-buffered saline group after 4 weeks of treatment. The current findings show that TNF-α inhibition can protect against the early stages of tendon tissue remodeling induced by stress shielding, but additional interventions may be necessary to prevent tendon degeneration with long-term stress shielding. [Orthopedics. 2017; 40(1):49-55.].

[Roles of biochemical factors in lateral compartment wear from varus knee osteoarthritis]

OBJECTIVE

To explore the roles of type II collagen C-terminal telopeptide (CTX-II), matrix metalloproteinase-13 (MMP-13) and interleukin-6 (IL-6) in lateral compartment wear in varus knee osteoarthritis.

METHODS

Prospective reviews were conducted for the clinical data of varus knee osteoarthritis patients with lateral compartment wear undergoing total knee arthropalsty from June 2013 to June 2014. The gross findings of lateral compartment articular cartilage were recorded intraoperatively. And the slices were evaluated histologically. Synovial fluid was obtained by arthrocentesis. An equal number of operative patients from varus knee osteoarthritis without lateral compartment wear during the same period were selected and matched with respects to age, varus, preoperative range of motion and radiological grade of knee arthrosis. Synovial fluid concentrations of CTX-II, MMP-13 and IL-6 were evaluated.

RESULTS

Histologic examination showed microscopic cartilage degeneration in both groups. The concentrations of CTX-II, IL-6 and MMP-13 in synovial fluid from lateral compartment wear group were (111.8±55.7) ng/L, (2.5±1.0) ng/L and (134.4±33.1) µg/L respectively. And there were no differences with control group (91.7±57.1) ng/L, (2.1±0.5) ng/L, (122.7±28.3) µg/L respectively.

CONCLUSION

The above biochemical factors may not play key roles in lateral compartment wear of varus knee osteoarthritis.

[EXPRESSIONS OF CARTILAGE DEGENERATIVE RELATED GENES AND microRNAs IN TORN MENISCUS]

OBJECTIVE

To investigate the expressions of cartilage degenerative related genes in meniscus, and to evaluate the potential effect of meniscal damage on cartilage degeneration, and to analyze the relationship between microRNAs (miRNAs) expression and cartilage degeneration.

METHODS

Meniscal tissue was collected from 5 patients undergoing partial meniscectomy between September 2012 and October 2013 (experimental group), and normally meniscal tissue without tearing from amputees was used as controls (control group). Pathological changes of menisci were observed; and real-time fluorescent quatitative PCR was performed to examine the relative expression levels of cartilage degenerative related genes and miRNAs: Aggrecan (ACAN), type X collagen (COL10A1), matrix metalloproteinases 13 (MMP-13), CCAAT enhancer binding protein β (CEBP-β), a disintegrin and metalloproteinase with thrombospondinmotif 5 (ADAMTS-5), miR-193b, miR-92a, and miR-455-3p in meniscus.

RESULTS

There were varying degrees of degenerative pathological changes in torn meniscus of experimental group. Compared with normal meniscus of control group, the expression of ACAN was decreased, while the expressions of COL10A1, CEBP-β, ADAMTS-5, and MMP-13 were increased in torn meniscus of experimental group; and significant difference was found (P < 0.05) except ACAN and MMP-13 (P > 0.05). The expressions of miR-92a, miR-455-3p, and miR-193b in torn meniscus of experimental group were significantly higher than those in normal meniscus of control group (P < 0.05).

CONCLUSION

Meniscal tissue has the intrinsic tendency of degeration after meniscus tear. The torn meniscus has greater stimulative impact on cartilage degeneration than normally morphological meniscus without tearing. The cartilage degenerative related miRNAs, including miR-193b, miR-92a, and miR-455-3p may contribute to the up-regulation of osteoarthritis.

[The invasion ability and expressions of matrix metalloproteinase-13 and calcium-binding protein S100A4 are inhibited by hyperthermia in human Tca8113 cells]

OBJECTIVE

To study the effect of hyperthermia on anti-invasion of Tca8113 and the expression change of matrix metalloproteinase-13 (MMP-13) and calcium-binding protein S100A4 (S100A4).

METHODS

Tca8113 cell pools were incubated at 43 degrees C for 0, 40, 80, 120 min, respectively, and at 37, 41, 43, 45 degrees C respectively for 80 min. The effect of high temperatures on the invasion ability of Tca8113 was measured in vitro. The slides of cells were made and incubated at 43 degrees C for 0, 40, 80, 120 min, respectively. Immunocytochemical method was employed for detecting the expression change of MMP-13 and S100A4 protein. Tca8113 cells were incubated at 43 degrees C for 0, 40, 80, 120 min respectively and at 37, 41, 43, 45 degrees C respectively for 80 min. Western blot method was conducted for detecting the expressionchange of MMP-13 and S100A4 protein.

RESULTS

As incubating time at higher temperature lasted, the proportion of the cells with invasion ability decreased. Except groups of 40 min and 80 min at 43 degrees C and 41, 43 degrees C for 80 min, the rest groups show significant statistic differences (P < 0.05). The expression intensity of MMP-13 and S100A4 proteins in Tca8113 cells would decrease as incubating time at higher temperature lasted. The content of MMP-13 and S100A4 proteins would decrease as incubating time at higher temperature lasted or incubating temperature increased. Except the groups of 40, 80 min at 43 degrees C and 41, 43 degrees C for 80 min, statistic differences were identified (P < 0.05).

CONCLUSION

The invasion of Tca8113 could be inhibited by hyperthermia. The mechanism of this effect may be due to protein expression inhibition of MMP-13 and S100A4.

Incorporation of vancomycin-supplemented bone allograftsRadiographical, histopathological and immunohistochemical study in pigs

We compared the incorporation of bone allografts with or without vancomycin in tibial defects of 18 pigs. High-quality radiographs, histological examination, immunological expression of metalloproteinase-13 (MMP-13) and transforming growth factor-beta 2 (TGFbeta2) indicated that there was no significant difference in bone allograft incorporation between up to 220 times the MIC (minimum inhibitory concentration) in bone allografts with 1 g of vancomycin in each 300 g of allograft or without this supplement.

The expression of collagenase 3 (MMP-13) mRNA in the synovial tissue is associated with histopathologic type II synovitis in rheumatoid arthritis

The histopathologic analysis of the synovial tissue is important to distinguish rheumatoid arthritis (RA) from other forms of synovitis and to provide information about prognosis and therapeutic strategies at early stages of the disease. In this context, the present study was performed to investigate the correlation between immunohistopathological and morphological features of synovitis and the expression of collagenase 3 (MMP-13) known to contribute significantly to cartilage degradation in RA. In the histopathologic scoring system used in this study, type I synovitis is characterized by B lymphocyte infiltration and an intact lining, and is only mild destructive to cartilage and bone. Type II shows marked diffuse infiltrations of macrophages and T lymphocytes, an ulcerated lining, fibrin exudation, and invasive growth into cartilage and bone tissue. Investigating 36 patients with RA, 21 patients (58%) were positive for the expression of collagenase 3 mRNA in the synovial tissue. Among these patients, 19 showed a histopathologic type II synovitis and only 2 patients had undifferentiated synovitis. In contrast, synovial tissue samples from patients without collagenase 3 mRNA expression were characterized in 6 cases by type I, in 5 cases by type II and in 4 cases by undifferentiated synovitis. The analysis of the clinical data revealed that RA patients with a histopathologic type II synovitis and synovial tissue collagenase 3 mRNA expression had elevated levels of systemic markers of inflammation and received stronger therapies. The data suggest, that collagenase 3 expression and the histopathologic type II synovitis are associated with a severe and destructive course of RA.

The signalling of AT2 and the influence on the collagen metabolism of AT2 receptor in adult rat cardiac fibroblasts

OBJECTIVES

Angiotensin (Ang) II exerts its roles on cardiac fibroblasts by two receptors: type I (AT1) and type 2 (AT2). The role of AT1 has been well known, but less is known about AT2. The present study was designed to explore signal pathways of AT2 and observe whether AT2 is involved in the collagen metabolism of cardiac fibroblasts.

METHODS AND RESULTS

Adult rat cardiac fibroblasts were extracted, cultured and treated with Ang-II alone, Ang-II plus losartan or PD123319. G protein-coupled receptors signalling pathway finder gene arrays were used to analyse expression changes of 96 genes associated with 11 signal pathways. With a 10-fold change in threshold, 7 genes were differentially expressed specific to AT1 blockade associated to 5 signal pathways including PKC, PLC, MAPK, NO/cGMP and NFkappaB; while 24 genes were specific to AT2 blockade related to 10 signal pathways including cAMP/PKA, Ca2+, PKC, PTK, MAPK, PI-3K, NO/cGMP, Rho, NFkappaB and JAK-STAT. RT-PCR were used to confirm the results of arrays and measure collagen (Col) I and tissue inhibitor of metalloproteinase (TIMP)-1 mRNA levels. AT2 blockade decreased Col I and TIMP-1 mRNA levels compared to the Ang II-treated group, which was similar with AT1 blockade.

CONCLUSION

In adult rat cardiac fibroblasts, AT2 was obviously distinct from AT1 in signalling responses. AT2 appeared to spread more widely than AT1. AT2 might be involved in the collagen metabolism of rat cardiac fibroblasts by regulating Col I and TIMP1 mRNA levels.