Inhibition of angiogenesis by arsenic trioxide via TSP-1-TGF-β1-CTGF-VEGF functional module in rheumatoid arthritis

The protective effect of natural medicines in rheumatoid arthritis via inhibit angiogenesis

Rheumatoid arthritis is a chronic immunological disease leading to the progressive bone and joint destruction. Angiogenesis, accompanied by synovial hyperplasia and inflammation underlies joint destruction. Delaying or even blocking synovial angiogenesis has emerged as an important target of RA treatment. Natural medicines has a long history of treating RA, and numerous reports have suggested that natural medicines have a strong inhibitory activity on synovial angiogenesis, thereby improving the progression of RA. Natural medicines could regulate the following signaling pathways: HIF/VEGF/ANG, PI3K/Akt pathway, MAPKs pathway, NF-κB pathway, PPARγ pathway, JAK2/STAT3 pathway, etc., thereby inhibiting angiogenesis. Tripterygium wilfordii Hook. f. (TwHF), sinomenine, and total glucoside of Paeonia lactiflora Pall. Are currently the most representative of all natural products worthy of development and utilization. In this paper, the main factors affecting angiogenesis were discussed and different types of natural medicines that inhibit angiogenesis were systematically summarized. Their specific anti-angiogenesis mechanisms are also reviewed which aiming to provide new perspective and options for the management of RA by targeting angiogenesis.

Overlapping approach Proton Pump Inhibitors/Nux vomica-Heel as new intervention for gastro-esophageal reflux management: Delphi consensus study

BACKGROUND

Gastro-esophageal reflux disease (GERD) may affect the upper digestive tract; up to 20% of population in Western nations are affected by GERD. Antacids, histamine H2-receptor antagonists, and Proton Pump Inhibitors (PPIs) are considered the referring medications for GERD. Nevertheless, PPIs must be managed carefully because their use, especially chronic, could be linked with some adverse effects. An effective and safe alternative pharmacological tool for GERD is needed. After the identification of potentially new medications to flank PPIs, it is mandatory to revise and improve good clinical practices even through a consensus process.

AIM

To optimize diagnosis and treatment guidelines for GERD through a consensus based on Delphi method.

METHODS

The availability of clinical studies describing the action of the multicomponent/multitarget medication Nux vomica-Heel, subject of the consensus, is the basic prerequisite for the consensus itself. A modified Delphi process was used to reach a consensus among a panel of Italian GERD specialists on the overlapping approach PPIs/Nux vomica-Heel as a new intervention model for the management of GERD. The Voting Consensus group was composed of 49 Italian Medical Doctors with different specializations: Gastroenterology, otolaryngology, geriatrics, and general medicine. A scientific committee analyzed the literature, determined areas that required investigation (in agreement with the multiple-choice questionnaire results), and identified two topics of interest: (1) GERD disease; and (2) GERD treatment. Statements for each of these topics were then formulated and validated. The Delphi process involved two rounds of questioning submitted to the panel experts using an online platform.

RESULTS

According to their routinary GERD practice and current clinical evidence, the panel members provided feedback to each questionnaire statement. The experts evaluated 15 statements and reached consensus on all 15. The statements regarding the GERD disease showed high levels of agreement, with consensus ranging from 70% to 92%. The statements regarding the GERD treatment also showed very high levels of agreement, with consensus ranging from 90% to 100%. This Delphi process was able to reach consensus among physicians in relevant aspects of GERD management, such as the adoption of a new approach to treat patients with GERD based on the overlapping between PPIs and Nux vomica-Heel. The consensus was unanimous among the physicians with different specializations, underlying the uniqueness of the agreement reached to identify in the overlapping approach between PPIs and Nux vomica-Heel a new intervention model for GERD management. The results support that an effective approach to deprescribe PPIs through a progressive decalage timetable (reducing PPIs administration to as-needed use), should be considered.

CONCLUSION

Nux vomica-Heel appears to be a valid opportunity for GERD treatment to favor the deprescription of PPIs and to maintain low disease activity together with the symptomatology remission.

BzATP reverses ferroptosis-induced gut microbiota disorders in collagen-induced arthritis mice

Recent studies suggested that altered gut microbiota may be related to the pathogenesis of rheumatoid arthritis (RA), albeit the exact mechanisms are unknown. In this study, we aimed to discover the particular mechanism of RA treatment by microbiota by investigating the effects of ferroptosis on gut microbiota and its metabolites in collagen-induced arthritis (CIA) mice. Mice were divided into five groups: control, CIA, erastin, BzATP, and BzATP + erastin group. We performed 16S rDNA sequencing and metabolomics analysis on mouse feces and found that erastin and BzATP altered the microbiota and metabolites. The findings demonstrated that the microbiota was significantly disturbed at the phylum (Proteobacteria, Firmicutes, and Bacteroidota) and genus level (Lachnospiraceae_NK4A136, Lactobacillus, and Bifidobacterium) in the CIA group, and erastin exacerbated this disturbance. Unexpectedly, BzATP treatment could repair the disruptive effects of erastin. Additionally, there were significant variations in metabolites between each group. Erastin worsened metabolite abnormalities in CIA mice, while BzATP mitigated them, consistent with the microbiota results. These findings provide novel perspectives and insights into the therapy of RA.

SMSCs-derived sEV overexpressing miR-433-3p inhibits angiogenesis induced by sEV released from synoviocytes under triggering of ferroptosis

BACKGROUND

Ferroptosis is characterized by accumulation of lipid peroxides that leads to oxidative stress. In progressive rheumatoid arthritis (RA), fibroblast-like synoviocytes (FLS) suffered from oxidative stress induced by generation of excess reactive oxygen species (ROS) and survived from elevated lipid oxidation. However the phenomenon of abnormal synovial fibroblasts proliferation under ferroptotic stress remain to be explained and the effects of this event on disease progression of RA need to be investigated.

METHODS

FLS from RA patients (RA-FLS) were stimulated with LPS as an inflammatory model in vitro, and simultaneously treated with ferroptosis inducer Erastin/RSL3 or inhibitor ferrostatin-1. Besides, small extracellular vesicles (sEV) from the supernatant of RA-FLS culture under Erastin/RSL3 management were isolated. The degree of ferroptosis in cells were evaluated by Lipid-ROS detection via flowcytometry and ferroptosis marker protein expression determined by western bloting. The expression of core component of ESCRT-III CHMP4A and CHMP5 was determined by western bloting, and knockdown of CHMP4A was further performed to detect the influence of ESCRT-III complex on ferroptosis as well as LPS/Erastin induced sEV (LPS/Erastin-sEV) releasing. Moreover, miR-433-3p level in the isolated sEV was evaluated by RT-qPCR and interaction of miR-433-3p with FOXO1/VEGF axis were evaluated. MiR-433-3p was overexpressed in synovial mesenchymal stem cells (SMSCs) via miR-433-3p mimics transfection. RA-FLS was co-cultured with human dermal microvascular endothelial cells (HDMECs). LPS/Erastin-sEV or sEV derived from miR-433-3p-overexpressing SMSCs (miR-433-3p-SMSCs-sEV) were added to the co-culture system, and supernatants from co-culture without sEV were given to HDMECs. Angiogenic activity of HDMECs were identified by transwell test and endothelial tube formation analysis. Erastin-sEV and miR-433-3p-SMSCs-sEV were also administrated in collagen-induced arthritis (CIA) mouse model respectively, and progression of arthritis were evaluated.

RESULTS

Ferroptosis of RA-FLS was triggered by LPS/Erastin and accompanied with increased expression of ESCRT-III core components as well as elevated release of sEV from RA-FLS. HDMECs' migration and tube formation in vitro was significantly induced/suppressed by supernatants from co-culture under management of Erastin-sEV/miR-433-3p-SMSCs-sEV due to varied VEGF expression regulated by miR-433-3p targeting FOXO1. MiR-433-3p-SMSCs-sEV could inhibit the Erastin-sEV promoted VEGF expression and mitigated arthritis severity.

CONCLUSION

Erastin-sEV could aggravate synovial angiogenesis and promote arthritis progression. Administration of miR-433-3p-SMSCs-sEV may be a potential novel therapeutic method as significant antagonism to Erastin-sEV for RA treatment.

Identification of ferroptosis related markers by integrated bioinformatics analysis and In vitro model experiments in rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is an autoimmune disease characterized by destructive and symmetrical joint diseases and synovitis. This research attempted to explore the mechanisms involving ferroptosis in RA, and find the biological markers by integrated analysis.

METHODS

Gene expression data (GSE55235 and GSE55457) of synovial tissues from healthy and RA individuals were downloaded. By filtering the differentially expressed genes (DEGs) and intersecting them with the 484 ferroptosis-related genes (FRGs), the overlapping genes were identified. After the enrichment analysis, the machine learning-based approaches were introduced to screen the potential biomarkers, which were further validated in other two datasets (GSE77298 and GSE93272) and cell samples. Besides, we also analyze the infiltrating immune cells in RA and their correlation with the biomarkers.

RESULTS

With the criteria, 635 DEGs in RA were included, and 29 of them overlapped in the reported 484 FRGs. The enrichments of the 29 differentially expressed ferroptosis-related genes indicated that they may involve in the FoxO signaling pathway and inherited metabolic disorder. RRM2, validating by the external datasets and western blot, were identified as the biomarker with the high diagnostic value, whose associated immune cells, such as Neutrophils and Macrophages M1, were also further evaluated.

CONCLUSION

We preliminary explored the mechanisms between ferroptosis and RA. These results may help us better comprehend the pathophysiological changes of RA in basic research, and provide new evidences for the clinical transformation.

Parthenolide and arsenic trioxide co-trigger autophagy-accompanied apoptosis in hepatocellular carcinoma cells

Although arsenic trioxide (ATO) shows a strong anti-tumor effect in the treatment of acute promyelocytic leukemia, it does not benefit patients with hepatocellular carcinoma (HCC). Thus, combination therapy is proposed to enhance the efficacy of ATO. Parthenolide (PTL), a natural compound, selectively eradicates cancer cells and cancer stem cells with no toxicity to normal cells. In this study, we chose PTL and ATO in combination and found that nontoxic dosage of PTL and ATO co-treatment can synergistically inhibit the in vitro and in vivo proliferation activity of HCC cells through suppressing stemness and self-renewal ability and inducing mitochondria-dependent apoptosis. More importantly, USP7-HUWE1-p53 pathway is involved in PTL enhancing ATO-induced apoptosis of HCC cell lines. Meanwhile, accompanied by induction of apoptosis, PTL and ATO evoke autophagic activity via inhibiting PI3K/Akt/mTOR pathway, and consciously controlling autophagy can improve the anti-HCC efficacy of a combination of PTL and ATO. In short, our conclusion represents a novel promising approach to the treatment of HCC.

Potential predictive and therapeutic applications of small extracellular vesicles-derived circPARD3B in osteoarthritis

Background: Heterogeneous phenotypes that display distinct common characteristics of osteoarthritis (OA) are not well defined and will be helpful in identifying more customized therapeutic options for OA. Circular RNAs (circRNAs) have attracted more and more attention due to their role in the progression of OA. Investigating the role of circRNAs in the pathogenesis of OA will contribute to the phenotyping of OA and to individualized treatment.

Methods: Small extracellular vesicles (sEV) were isolated from serum samples from patients with OA of different stages and sEV-derived circPARD3B was determined using RT-qPCR analysis. CircPARD3B expression in a stimulated coculture that included OA fibroblast-like synoviocytes (OA-FLS) as well as human dermal microvascular endothelial cells (HDMECs), plus the effects of circPARD3B on the expression of vascular endothelial growth factor (VEGF) long with angiogenic activity, were evaluated in vitro. Based on bioinformatics analysis and luciferase reporter assay (LRA), MiR-326 and sirtuin 1 (SIRT1) were found to be interactive partners of circPARD3B. Mesenchymal stem cells (SMSCs) overexpressing circPARD3B were constructed and SMSCs-derived sEV with overexpressed circPARD3B (OE-circPARD3B-SMSCs-sEV) were obtained to explore the effect of the intervention of circPARD3B combined with SMSCs-sEV-based therapy in vitro and in a OA model induced by collagenase in vivo.

Results: Serum sEV-linked circPARD3B was indentified to be significantly decreased in the inflammatory phenotype of OA. Overexpression of circPARD3B was found to inhibit the expression of VEGF, as well as the angiogenesis induced by VEGF in a IL-1β stimulated the co-culture of OA-FLS as well as HDMECs. CircPARD3B is directly bound to miR-326. SIRT1 was considered a novel miR-326 target gene. OE-circPARD3B-SMSCs-sEV significantly reduced VEGF expression in coculture of OA-FLS and HDMECs. Injection of OE-circPARD3B-SMSCs-sEV could also reduce synovial VEGF; additionally, it could further ameliorate OA in the mouse model of OA in vivo.

Conclusion: Serum sEV circPARD3B is a potential biomarker that enables the identification of the inflammatory phenotype of patients with OA. Correspondingly, intracellular transfer of circPARD3B through OE-circPARD3B-SMSCs-sEV could postpone disease progression through a functional module regulated angiogenesis of circPARD3B-miR-326-SIRT1, providing a novel therapeutic strategy for OA.

Arsenic trioxide modulates the composition and metabolic function of the gut microbiota in a mouse model of rheumatoid arthritis

The mechanism of rheumatoid arthritis (RA) has been widely investigated, and studies on the use of arsenic trioxide (ATO) in the treatment of RA have been reported in recent years. However, the exact mechanism of action of ATO in RA remains unclear. This study explores alterations in the gut microbiota and metabolism during ATO treatment in a mouse model of RA and provides an integrative analysis of the biomechanism. The purpose of this study was to verify whether ATO can alleviate RA by altering the gut microbiota. In this study, the mice were randomly divided into four different groups: the normal control (NC) group, the collagen-induced arthritis (CIA) group, the ATO 1.0 mg/kg/day group, and the ATO 2.0 mg/kg/day group. Fecal samples were collected. Through 16S rDNA gene sequencing and metabolomic analysis, the effect of ATO on the composition and metabolites of gut microbiota in CIA mice was investigated. The results showed that compared with NC mice, CIA mice showed differences at both the phylum level (Firmicutes and Bacteroidetes) and the genus level (Muribaculaceae_unclassified and Alistipes). Meanwhile, many metabolites were significantly changed between the two groups, including benzoic acid and (s)-2-acetolactate. However, these alterations were partially reversed in ATO-treated CIA mice. These results indicated that ATO treatment modulated gut microbiota disorder and improved fecal metabolite abnormalities. In conclusion, this study provided important evidence for alterations of the gut microbiota and metabolites and the role of these alterations in a potential novel mechanism of ATO treatment in RA.

NR4A1-3 nuclear receptor activity and immune cell dysregulation in rheumatic diseases

The development and progression of immune-mediated rheumatic disease (IMRD) involves dysfunction of innate and adaptive immune cell populations leading to altered responses including inflammasome activation, dysregulated cytokine networks, increased immune cell numbers and multifaceted cell-cell communication. Several rheumatic diseases are further characterized by the presence of autoantibodies, immune complex mediated complement activation and the deficit of peripheral immune tolerance due to reduced regulatory T-lymphocyte cell function. Ultimately, in rheumatic disease the loss in cellular and tissue homeostasis culminates in the advancement of chronic inflammation. The three members of the NR4A subfamily of nuclear receptors are immediate early genes, and act as potent transcriptional responders to changes in the cellular and tissue microenvironment. Subfamily members are rapidly expressed in diseases characterized by inflammation and function to control the differentiation and activity of innate and adaptive immune cells in a cell-type and cell-context specific manner. Rheumatic disease including rheumatoid-, psoriatic-, osteo-arthritis and systemic sclerosis display altered NR4A1-3 activity in controlling immune cell migration and function, production of paracrine signaling molecules, synovial tissue hyperplasia, and regulating cartilage turn-over in vivo. Additionally, NR4A1-3 activities mediate cytokine, prostanoid and growth factor signaling to control angiogenesis, modulate the regulatory functions of mesenchymal stromal cells, alter the activation status of dendritic cells, influence the generation of peripheral myeloid and T-lymphocyte lineages and promote the maintenance of functional regulatory T-cells. Further reports uncover the potential of moderating NR4A 1-3 receptors as therapeutic targets in altering immune tolerance, pathological angiogenesis and controlling inflammation in several models of disease.

Transcriptomic profiling revealed the role of apigenin-4'-O-α-L-rhamnoside in inhibiting the activation of rheumatoid arthritis fibroblast-like synoviocytes via MAPK signaling pathway

BACKGROUND

Activated fibroblast-like synoviocyte (FLS) played a significant role in the pathogenesis and progression of rheumatoid arthritis (RA). Apigenin-4'-O-α-L-rhamnoside showed remarkable effects against RA, however, no relevant studies on pharmacology of apigenin-4'-O-α-L-rhamnoside yet, the effects and underlying molecular mechanism of apigenin-4'-O-α-L-rhamnoside on RA are still unclear.

PURPOSE

This study aimed to investigate the therapeutic effects and mechanisms of apigenin-4'-O-α-L-rhamnoside on RA-FLS cells by transcriptomic analysis.

METHODS

In vitro, RA-FLS cell viability and migration were measured by CCK-8 and scratch assays, respectively. The effects of apigenin-4'-O-α-L-rhamnoside on inflammatory levels of MMP-1, MMP-3, RANKL and TNF-α in RA-FLS cells were detected using ELISA kits. High-throughput transcriptome analysis was performed to screen the key genes and related pathways of apigenin-4'-O-α-L-rhamnoside inhibit RA-FLSs, and the result of which were validated by RT-qPCR and western blot. Furthermore, in vivo, we also evaluated the effects of apigenin-4'-O-α-L-rhamnoside in rat with CIA.

RESULTS

Apigenin-4'-O-α-L-rhamnoside significantly suppressed RA-FLS migration, exerted remarkable inhibiting effects on the expression levels on MMP-1, MMP3, RANKL and TNF-α in RA-FLS cells. It seemed that MAPK signaling pathway might be closely related to the pathogenesis of RA by down-regulated relevant core targets (MAPK1, HRAS, ATF-2, p38 and JNK). Moreover, apigenin-4'-O-α-L-rhamnoside attenuated the severity of arthritis in CIA rat.

CONCLUSION

Apigenin-4'-O-α-L-rhamnoside inhibited pro-inflammatory cytokine, chemokine and MMPs factors production of RA-FLS by targeting the MAPK signaling pathway, which provided a scientific basis for potential application in the treatment of RA.

Geniposide alleviates VEGF-induced angiogenesis by inhibiting VEGFR2/PKC/ERK1/2-mediated SphK1 translocation

BACKGROUND

Rheumatoid arthritis (RA) is an angiogenesis-dependent disease caused by the imbalance of pro- and anti-angiogenic factors. More effective strategies to block synovial angiogenesis in RA should be studied. Geniposide (GE), a natural product isolated from the fruit of Gardenia jasminoides Ellis (GJ), is reported to have anti-inflammatory, anti-angiogenic and other pharmacological effects. However, the underlying mechanism through which GE affects synovial angiogenesis in RA remains unclear.

PURPOSE

In this research, we aimed to elucidate the effect and potential mechanisms of GE on angiogenesis in RA.

MATERIALS AND METHODS

Synovial angiogenesis in patients with RA and a rat model of adjuvant arthritis (AA) was detected by hematoxylin and eosin (HE) staining, immunohistochemistry (IHC), and western blottiing. The biological functions of vascular endothelial cells (VECs) and sphingosine kinase 1 (SphK1) translocation were checked by CCK-8, EdU, Transwell, tube formation, co-immunoprecipitation assays, and laser scanning confocal microscopy. The effect of the SphK1 gene on angiogenesis was assessed by transfection of SphK1-siRNA in cells and mices. The effect of GE on VEGF-induced angiogenesis was measured by Matrigel plug assay in a mouse model of AA.

RESULTS

GE effectively inhibited synovial angiogenesis and alleviated the disease process. SphK1, as a new regulatory molecule, has a potentially important relationship in regulating VEGF/VEGFR2 and S1P/S1PR1 signals. SphK1 translocation was activated via the VEGFR2/PKC/ERK1/2 pathway and was closely linked to the biological function of VECs. GE significantly reduced SphK1 translocation, thereby ameliorating the abnormal biological function of VECs. Furthermore, after transfection of SphK1 siRNA in VECs and C57BL/6 mice, silencing SphK1 caused effectively attenuation of VEGF-induced VEC biological functions and angiogenesis. In vivo, the Matrigel plug experiment indicated that GE significantly inhibited pericyte coverage, basement membrane formation, vascular permeability, and fibrinogen deposition.

CONCLUSIONS

Our findings suggest that GE inhibited VEGF-induced VEC biological functions and angiogenesis by reducing SphK1 translocation. Generally, studies have revealed that GE down-regulated VEGFR2/PKC/ERK1/2-mediated SphK1 translocation and inhibited S1P/S1PR1 signaling activation, thereby alleviating VEGF-stimulated angiogenesis. The above evidences indicated that angiogenesis inhibition may provide a new direction for RA treatment.

Therapeutic Potential of Exosomal circRNA Derived from Synovial Mesenchymal Cells via Targeting circEDIL3/miR-485-3p/PIAS3/STAT3/VEGF Functional Module in Rheumatoid Arthritis

Background

Synovial inflammation and its associated activation of angiogenesis play critical roles in rheumatoid arthritis (RA). Exosomes, as carriers of genetic information including circular RNAs (circRNAs), have been explored as delivery vehicles for therapeutic molecules. However, the effects of synovial mesenchymal stem cells (SMSCs)-derived exosomal circRNAs and their mechanisms of action in RA progression remain unclear.

Methods

SMSCs-derived exosomes (SMSCs-Exos) were administered to a co-culture of RA fibroblast-like synoviocytes (RA-FLS) and human dermal microvascular endothelial cells (HDMECs) in vitro as well as to a collagen-induced arthritis (CIA) mouse model in vivo. Their effects on VEGF expression and angiogenic activity in vitro and the therapeutic efficacy in vivo were evaluated. Exosomes from circEDIL3-overexpressing SMSCs (Ad-circEDIL3-SMSCs-Exos) were used to further determine the role of circEDIL3 in SMSCs-Exo-based therapy.

Results

Both SMSCs-Exos and Ad-circEDIL3-SMSCs-Exos significantly downregulated the expression of VEGF induced by the IL-6/sIL-6R complex in the supernatants of RA-FLS and HDMECs co-culture as well as in the cell lysate of co-cultured RA-FLS, and the extent of reduction was more pronounced in the latter. Subsequent experiments showed that angiogenic activity was significantly downregulated by SMSCs-Exos and Ad-circEDIL3-SMSCs-Exos due to reduced VEGF expression. CircEDIL3 functioned as a sponge for miR-485-3p, which targeted PIAS3. PIAS3 is known to suppress STAT3 activity and reduce downstream VEGF. Injection of SMSCs-Exos or Ad-circEDIL3-SMSCs-Exos reduced synovial VEGF and consequently ameliorated arthritis severity in the CIA mouse model.

Conclusion

The intracellular transfer of circEDIL3 by SMSCs-Exos may be a potential novel therapeutic strategy for RA.

Angiogenesis is Inhibited by Arsenic Trioxide Through Downregulation of the CircHIPK3/miR-149-5p/FOXO1/VEGF Functional Module in Rheumatoid Arthritis

Angiogenesis is a crucial event in the pathogenesis of rheumatoid arthritis (RA). Arsenic trioxide (ATO, As₂O₃) has been reported to inhibit synovial angiogenesis via the vascular endothelial growth factor (VEGF)-centered functional module. However, the exact mechanisms of ATO on VEGF modulation remain unclear. Circular RNAs (circRNAs) are emerging as important regulators in RA, and the detailed mechanisms remain largely unknown. Here, we reported a circRNA (circHIPK3), the expression of which was significantly increased in RA fibroblast-like synoviocytes (RA-FLS) after TNF-α induction. Moreover, VEGF content in the supernatants of a RA-FLS and human dermal microvascular endothelial cell (HDMEC) co-culture as well as in RA-FLS co-cultured was significantly elevated in accordance with circHIPK3 levels. This increased VEGF expression may significantly upregulate endothelial tube formation and transwell migration, as well as microvessel sprouting in the ex vivo aortic ring assay. CircHIPK3 was further illustrated to be a sponge for the forkhead box transcription factor O1 (FOXO1)-targeting miR-149-5p, leading to the changing expression of the downstream VEGF. These networked factors mainly form a functional module regulating angiogenesis in RA-FLS, and the expression of this functional module could be significantly downregulated by ATO with a consistently reduced vascularity in vitro. In the collagen-induced arthritis (CIA) mice model, an intra-articular injection of the adeno-associated virus-si-circHIPK3 or ATO was demonstrated to alleviate the synovial VEGF expression and arthritis severity respectively. Thus, we elucidate a previously unknown mechanism between circRNAs and RA, and ATO has a significant protective effect on RA-FLS and CIA synovium via its inhibition of the angiogenic functional module of circHIPK3/miR-149-5p/FOXO1/VEGF, suggesting great potential for the combination therapy of ATO with circHIPK3 silencing.

Matrine inhibits synovial angiogenesis in collagen-induced arthritis rats by regulating HIF-VEGF-Ang and inhibiting the PI3K/Akt signaling pathway

Matrine (Mat) is an alkaloid of tetracycline quinazine, and previous studies have demonstrated its specific effect on relieving rheumatoid arthritis (RA). However, the effect of Mat on joint synovial angiogenesis in the pathogenesis of RA has not been elucidated. In this study, body weight, joint swelling, arthritis index (AI) score, histopathological changes, immunohistochemical, and western blot- were used in collagen-induced arthritis (CIA) rats to detect pro-inflammatory factors and, - expression levels of key cytokines and proteins along the hypoxia-inducible factor (HIF)-endothelial growth factor (VEGF)-angiopoietin (Ang) axis and VEGF-phosphoinositide 3-kinase (PI3K) / protein kinase B (Akt) pathway. In vitro experiments were conducted to observe the effect of Mat on the proliferation, migration and lumen formation of RA-fibroblast-like synovial cells (FLS) and human umbilical vein endothelial cells (HUVECs). Results showed that Mat reduced the degree of paw swelling and AI score in CIA rats, joint synovial tissue proliferation, inflammatory cell infiltration, and neovascularization; moreover, it down-regulated the expression levels of inflammatory factors interleukin-1β, interferon-γ, and pro-angiogenic factors VEGF, placental growth factor, HIF-α, Ang-1, Ang-2, Tie-2, and phosphorylation-Akt in the ankle joint of CIA rats. In addition, the in vitro experiments showed that Mat inhibited the proliferation and migration of RA-FLS and inhibited the proliferation and lumen formation of HUVECs. Therefore, Mat exerts an anti-angiogenesis effect by regulating the HIF-VEGF-Ang axis and inhibiting the PI3K/Akt signaling pathway. This inhibits the pathogenesis and improve the symptoms of RA, and may be offered as a candidate drug for the treatment of RA.

Angiogenesis as a potential treatment strategy for rheumatoid arthritis

Angiogenesis is an early and key event in the pathogenesis of rheumatoid arthritis (RA) and is crucial for the proliferation of synovial tissue and the formation of pannus. This process is regulated by both angiogenesis-stimulating factors and angiogenesis inhibitors, the basis for the "on-off hypothesis of angiogenesis." In RA, inflammation, immune imbalance, and hypoxia can further turn on the switch for blood vessel formation and induce angiogenesis. The new vasculature can recruit white blood cells, induce immune imbalance, and aggravate inflammation. At the same time, it also can provide oxygen and nutrients for the proliferating synovial tissue, which can accelerate the process of RA. The current therapies for RA mainly target the inflammatory response of autoimmune activation. Although these therapies have been greatly improved, there are still many patients whose RA is difficult to treat or who do not fully respond to treatment. Therefore, new innovative therapies are still urgently needed. This review covers the mechanism of synovial angiogenesis in RA, including the detailed process of angiogenesis and the relationship between inflammation, immune imbalance, hypoxia, and synovial angiogenesis, respectively. At the same time, in the context of the development of angiogenesis inhibition therapy for cancer, we also discuss similar treatment strategies for RA, especially the combination of targeted angiogenesis inhibition therapy and immunotherapy.

IL-34 affects fibroblast-like synoviocyte proliferation, apoptosis and function by regulating IL-17

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by proliferation and insufficient apoptosis of fibroblast-like synoviocytes (FLSs).The biology and functions of interleukin (IL)-34 are only beginning to be uncovered. We previously demonstrated IL-34 could upregulate the expression of IL-17 in RA patients. In this study, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry of Annexin V and PI staining were performed to assess cell proliferation and apoptosis progression in RA-FLSs after stimulated with increasing concentrations of IL-34, respectively. Inflammatory cytokines and angiogenic factors were measured using quantitative real-time PCR, Western blotting and ELISA. We explored the association between IL-34 and RA-FLS proliferation and apoptosis in the context of RA. Stimulating RA-FLSs with different concentrations of IL-34 significantly promoted the proliferation and inhibited the apoptosis of RA-FLSs in a concentration-dependent manner. Neutralization of IL-17 with the IL-17 inhibitor plumbagin (PB) reduced the effects of IL-34. Proinflammatory cytokine (IL-17A IL-6 and tumor necrosis factor-α, TNF-α) and angiogenic factor (vascular endothelial growth factor, VEGF and hypoxia-inducible factor-1α, HIF-1α) expression was markedly upregulated in RA-FLSs stimulated by IL-34. PB-mediated inhibition of IL-17A also decreased the expression of IL-6, TNF-α, HIF-1α and VEGF in RA-FLSs. Taken together, these findings suggest that targeting IL-34 production in RA-FLSs may be a therapeutic strategy for RA.

Geniposide downregulates the VEGF/SphK1/S1P pathway and alleviates angiogenesis in rheumatoid arthritis in vivo and in vitro

The VEGF/SphK1/S1P pathway is closely related to angiogenesis in rheumatoid arthritis (RA), but the precise underlying mechanisms are unclear at present. Here, we explored the involvement of the VEGF/SphK1/S1P cascade in RA models and determined the effects of GE intervention. Our results showed abnormal expression of proteins related to this pathway in RA synovial tissue. Treatment with GE effectively regulated the signal axis, inhibited angiogenesis, and alleviated RA symptoms. In vitro, TNF-ɑ enhanced the VEGF/SphK1/S1P pathway in a co-culture model of fibroblast-like synoviocytes (FLS) and vascular endothelial cells (VEC). GE induced downregulation of VEGF in FLS, restored the dynamic balance of pro-/antiangiogenic factors, and suppressed SphK1/S1P signaling in VEC, resulting in lower proliferation activity, migration ability, tube formation ability, and S1P secretion ability of VEC cells. Additionally, SphK1-specific small interfering RNA (siRNA) blocked the VEGF/SphK1/S1P cascade, which can effectively alleviate the stimulatory effect of FLS on VEC and further enhanced the therapeutic effect of GE. Taken together, our results demonstrate that GE suppresses the VEGF/SphK1/S1P pathway and alleviates the stimulation of VEC by FLS, thereby preventing angiogenesis and promoting therapeutic effects against RA.

Single Cell RNA-Seq Analysis Identifies Differentially Expressed Genes of Treg Cell in Early Treatment-Naive Rheumatoid Arthritis By Arsenic Trioxide

Objective: Early treatment-naïve rheumatoid arthritis (RA) has defective regulatory T (Treg) cells and increased inflammation response. In this study, we aim to illustrate the regulation of Treg cells in pathogenesis of early rheumatoid arthritis by arsenic trioxide (As₂O₃).

Methods: We studied the effects of As₂O₃ on gene expression in early treatment-naïve RA Treg cells with single cell RNA-seq (scRNA-seq). Treg cells were sorted from peripheral blood mononuclear cells (PBMCs) and purified by fluorescence-activated cell sorting (FACS) and cultured with or without As₂O₃ (at 0.1 µM) for 24 h. Total RNA was isolated and sequenced, and functional analysis was performed against the Gene Ontology (GO) database. Results for selected genes were confirmed with RT-qPCR.

Results: As₂O₃ exerts no significant effect on CD4⁺ T-cell apoptosis under physical condition, and selectively modulate ^CD4+ T cells toward Treg cells not Th17 cells under special polarizing stimulators. As₂O₃ increased the expression of 200 and reduced that of 272 genes with fold change (FC) 2.0 or greater. Several genes associated with inflammation, Treg-cell activation and differentiation as well as glucose and amino acids metabolism were among the most strongly affected genes. GO function analysis identified top ten ranked significant biological process (BPs), molecular functions (MFs), and cell components (CCs) in treatment and nontreatment Treg cells. In GO analysis, genes involved in the immunoregulation, cell apoptosis and cycle, inflammation, and cellular metabolism were enriched among the significantly affected genes. The KEGG pathway enrichment analysis identified the forkhead box O (FoxO) signal pathway, apoptosis, cytokine–cytokine receptor interaction, cell cycle, nuclear factor-kappa B (NF-κB) signaling pathway, tumor necrosis factor α (TNF-α), p53 signaling pathway, and phosphatidylinositol 3′-kinase (PI3K)-Akt signaling pathway were involved in the pathogenesis of early treatment-naïve RA.

Conclusion: This is the first study investigating the genome-wide effects of As₂O₃ on the gene expression of treatment-naïve Treg cells. In addition to clear anti-inflammatory and immunoregulation effects, As₂O₃ affect amino acids and glucose metabolism in Treg cells, an observation that might be particularly important in the metabolic phenotype of treatment-naïve RA.

Comparative transcriptomics and network pharmacology analysis to identify the potential mechanism of celastrol against osteoarthritis

INTRODUCTION

Celastrol is a promising therapeutic agent for the treatment of osteoarthritis (OA). However, the mechanism of action of celastrol is unclear. This study was aiming to identify the potential function of celastrol on OA and determine its underlying mechanism.

METHOD

Celastrol targets were collected from web database searches and literature review, while pathogenic OA targets were obtained from Online Mendelian Inheritance in Man (OMIM) and GeneCards databases. Transcriptomics data was sequenced using an Illumina HiSeq 4000 platform. Celastrol-OA overlapping genes were then identified followed by prediction of the potential function and signaling pathways associated with celastrol using gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. A celastrol-target network was constructed to identify the candidate core targets of celastrol. The predictions were then validated by performing molecular docking and molecular dynamics simulation studies.

RESULTS

In total, 96 genes were identified as the putative celastrol targets for treatment of OA. These genes were possibly involved in cell phenotype changes including response to lipopolysaccharide and oxidative stress as well as in cell apoptosis and aging. The genes also induced the mTOR pathway and AGE-RAGE signaling pathway at the intracellular level. Additionally, results indicated that 13 core targets including mTOR, TP53, MMP9, EGFR, CCND1, MAPK1, STAT3, VEGFA, CASP3, TNF, MYC, ESR1, and PTEN were likely direct targets of celastrol in OA. Finally, mTOR was determined as the most likely therapeutic target of celastrol in OA.

CONCLUSION

This study provides a basic understanding and novel insight into the potential mechanism of celastrol against OA. Key Points • Our study provides a strong indication that further study of celastrol therapy in OA is required. • mTOR is the most likely therapeutic target of celastrol in OA.

Antiangiogenic effect of arsenic trioxide in HUVECs by FoxO3a-regulated autophagy

Arsenic trioxide (ATO) has been shown to have antitumor effect in different tumors, although the underlying mechanisms are not fully understood. Autophagy plays a critical role in tumorigenesis and cancer therapy and has been found to be activated by ATO in different cells. However, the role of autophagy in the antitumor effect of ATO has not yet been elucidated. In this study, we investigated the role of autophagy in the antiangiogenic effect of ATO in human umbilical vein endothelial cells (HUVECs) in vitro and its underlying mechanism. Our data showed that ATO suppresses angiogenesis and induces autophagy in HUVECs through upregulation of forkhead box protein O3 (FoxO3a). Co-incubated with autophagy inhibitor or knockdown of FoxO3a effectively inhibited ATO-induced autophagy and reversed the antiangiogenic effect of ATO, indicating that ATO-induced autophagy plays an antiangiogenic role in HUVECs. Our results highlight the importance of autophagy in the antiangiogenic effect of ATO and provide an improved understanding of the function of ATO.

Traditional and modern management strategies for rheumatoid arthritis

Rheumatoid arthritis (RA) is a serious disorder of the joints affecting 1 or 2% of the population aged between 20 and 50 years worldwide. RA is the foremost cause of disability in developing and Western populations. It is an autoimmune disease-causing inflammation and pain involving synovial joints. Pro-inflammatory markers, including cytokines, such as interleukin -1 (IL-1), IL-6, IL-7, IL-8, and tumor necrosis factor-α (TNF-α) are involved in RA. RA treatment involves TNF-α blockade, B cell therapy, IL-1 and IL-6 blockade, and angiogenesis inhibition. Synthetic drugs available for the treatment of RA include disease-modifying anti-rheumatic drugs (DMARD), such as cyclophosphamide, sulfasalazine, methotrexate, nonsteroidal anti-inflammatory drugs (NSAIDs), and intramuscular gold. These agents induce adverse hepatorenal effects, hypertension, and gastric ulcers. We found that patients diagnosed with chronic pain, as in RA, and those refractory to contemporary management are most likely to seek traditional medicine. Approximately 60-90% of patients with arthritis use traditional medicines. Therefore, the efficacy and safety of these traditional medicines need to be established. The treatment for RA entails a comprehensive multidisciplinary strategy to reduce pain and inflammation and to restore the activity of joints. The potential medicinal plants exhibiting anti-arthritic and anti-rheumatic pharmacological activity are reviewed here.

miR-296-5p inhibits IL-1β-induced apoptosis and cartilage degradation in human chondrocytes by directly targeting TGF-β1/CTGF/p38MAPK pathway

Osteoarthritis (OA) is characterized by apoptosis of chondrocytes and an imbalance of extracellular matrix (ECM) synthesis and catabolism. Emerging evidence has demonstrated that miRNAs are involved in OA pathologies, but the role of miR-296-5p in OA remains unclear. The present study proposes to reveal the functions and mechanisms of miR-296-5p in a cell model of OA. In this study, human chondrocytes were treated with 5 ml interleukin-1 beta (IL-1β) to induce apoptosis and cartilage degradation. Our results showed that miR-296-5p was downregulated in chondrocytes stimulated with IL-1β. Overexpressed miR-296-5p enhanced cell proliferation and inhibited apoptosis and matrix degrading enzyme expression in response to IL-1β stimulation, and knockdown of miR-296-5p showed the opposite effect. Further, we found that miR-296-5p directly targeted the 3'-untranslated region (3'-UTR) of TGF-β1 mRNA, and miR-296-5p inactivated the TGF-β1/CTGF/p38MAPK signaling pathway. Overexpression of TGF-β1 alleviated the inhibition of miR-296-5p on chondrocyte apoptosis and cartilage degradation. In conclusion, miR-296-5p inhibited the progression of OA through the CTGF/p38MAPK pathway by directly targeting TGF-β1.

B7-H3 modulates endothelial cell angiogenesis through the VEGF cytokine

B7-H3 is a cell surface molecule in the immunoglobulin superfamily that has been shown to perform both immunological and non-immunological functions. It has also been found that vascular endothelial growth factor (VEGF) is an important molecule in the modulation of endothelial cell behavior. In this study, we analyzed the serum expression of B7-H3 in 113 rheumatoid arthritis and systemic lupus erythematous patients using the ELISA and found a positive correlation between B7-H3 and VEGF. Next, we investigated the involvement of B7-H3 in angiogenesis using human umbilical vein endothelial cells (HUVECs) with transient knockdown of B7-H3 and an in vivo Matrigel model. Data from the in vitro experiments showed that B7-H3 increased cell proliferation, migration, and tube formation, and correlated with the expression of VEGF. Furthermore, B7-H3 affected the formation of functional vascular networks in Matrigel plugs, which were dissected from mice injected with different HUVECs. Our data suggest that B7-H3 promotes angiogenesis through the enhancement of VEGF secretion. This is the first study proposing a significant role for B7-H3 in the promotion of angiogenesis and may provide further understanding of this gene's biological function.

Potential molecular mechanisms underlying the effect of arsenic on angiogenesis

Arsenic is a potent chemotherapeutic drug that is applied as a treatment for cancer; it exerts its functions through multiple pathways, including angiogenesis inhibition. As angiogenesis is a critical component of the progression of many diseases, arsenic is a feasible treatment option for patients with other angiogenic diseases, including rheumatoid arthritis and psoriasis, among others. However, arsenic is also a well-known carcinogen, demonstrating a pro-angiogenesis effect. This review will focus on the dual effects of arsenic on neovascularization and the relevant mechanisms underlying these effects, aiming to provide a rational understanding of arsenic treatment. In particular, we expect to provide a comprehensive overview of the current knowledge of the mechanisms by which arsenic influences angiogenesis.

Data on arsenic trioxide modulates Treg/Th17/Th1/Th2 cells in treatment-naïve rheumatoid arthritis patients and collagen-induced arthritis model mice

In this article, we share the raw protein and mRNA data obtained from basal and stimulated human peripheral blood mononuclear cells (PBMCs) derived from 15 individual treatment-naïve rheumatoid arthritis (RA) patients and synovial fluid mononuclear cells (SFMCs). In treatment-naïve RA patients, PBMCs were treated with a gradient of concentrations of As₂O₃ (0, 0.1, 0.5, 1.0, 2.0, 4.0 μM) for 48 hours. We found that 2.0 μM As₂O₃ promoted the apoptosis of PBMCs significantly, and 0.5 μM As₂O₃ was the lowest and effective concentration that contributed to Treg cell generation but it prevented Th17 cell differentiation, as assessed by flow cytometry. Furthermore, As₂O₃ decreased the transcription factor STAT3 mRNA expression of Th17 cells but increased the transcription factor Foxp3 of Treg cells. In synovial fluid from RA patients, consistent with PBMCs, As₂O₃ inhibited Th17 cell differentiation but promoted Treg cell generation. In an animal experiment, we analyzed the body-weight of mice as the indicator of As₂O₃ toxicity and calculated the spleen index. As₂O₃ significantly decreased the hematoxylin and eosin score in Type II collagen-induced arthritis in mice. Furthermore, As₂O₃ downregulated the frequency of Th1 but upregulated Th2 cells. For more insight please see Arsenic trioxide improves Treg and Th17 balance by modulating STAT3 in treatment-naive rheumatoid arthritis patients [1].

Transforming growth factor β signaling pathway: A promising therapeutic target for cancer

Transforming growth factor β (TGF-β) is part of the transforming growth factor β superfamily which is involved in many physiological processes and closely related to the carcinogenesis. Here, we discuss the TGF-β structure, function, and its canonical Smads signaling pathway. Importantly, TGF-β has been proved that it plays both tumor suppressor as well as an activator role in tumor progression. In an early stage, TGF-β inhibits cell proliferation and is involved in cell apoptosis. In an advanced tumor, TGF-β signaling pathway induces tumor invasion and metastasis through promoting angiogenesis, epithelial-mesenchymal transition, and immune escape. Furthermore, we are centered on updated research results into the inhibitors as drugs which have been studied in preclinical or clinical trials in tumor carcinogenesis to prevent the TGF-β synthesis and block its signaling pathways such as antibodies, antisense molecules, and small-molecule tyrosine kinase inhibitors. Thus, it is highlighting the crucial role of TGF-β in tumor therapy and may provide opportunities for the new antitumor strategies in patients with cancer.

Arsenic Trioxide in Synergy with Vitamin D Rescues the Defective VDR-PPAR-γ Functional Module of Autophagy in Rheumatoid Arthritis

Dysregulated autophagy leads to autoimmune diseases including rheumatoid arthritis (RA). Arsenic trioxide (ATO) is a single agent used for the treatment of acute promyelocytic leukemia and is highly promising for other malignancies but is also attractive for RA, although its relationship with autophagy remains to be further clarified and its application optimized. For the first time, we report a defective functional module of autophagy comprising the Vitamin D receptor (VDR), PPAR-γ, microtubule-associated protein 1 light-chain 3 (LC3), and p62 which appears in RA synovial fibroblasts. ATO alleviated RA symptoms by boosting effective autophagic flux through significantly downregulating p62, the inflammation and catabolism protein. Importantly, low-dose ATO synergizes with Vitamin D in RA treatment.

Sinomenine mitigates collagen-induced arthritis mice by inhibiting angiogenesis

OBJECTIVE

The objective of the present study is to investigate the inhibitory effects of sinomenine (SIN) on angiogenesis in a collagen-induced arthritis (CIA) mouse model.

METHODS

Arthritis assessments for all mice were recorded. The histopathological assessments were performed following haematoxylin and eosin (HE) staining. Immunohistochemistry and enzyme-linked immunosorbent assay (ELISA) analyses were used to detect the expression of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) and angiopoietin 1 (ANG-1) in the serum and in the membrane. Immunohistochemistry was employed to detect the synovium microvessel density (MVD).

RESULTS

Compared with the CIA model group, SIN significantly ameliorated swelling and erythema extension, decreased the arthritis index, reduced inflammation, cartilage damage and bone erosion, and lessened the number of CD31 positive cells on the synovium. Moreover, the levels of HIF-1α, VEGF and ANG-1 in the synovium and in the peripheral serum were increased in the untreated CIA model group but were significantly reduced in the 30 mg/kg, 100 mg/kg and 300 mg/kg SIN treatment groups.

CONCLUSION

SIN could mitigate CIA by inhibiting angiogenesis, and the mechanism may associate with the HIF-1α-VEGF-ANG-1 axis. Additionally, our study provides a referable experimental basis for the use of SIN for the treatment of rheumatoid arthritis.

Bi-directional regulation of TGF-β/Smad pathway by arsenic: A systemic review and meta-analysis of in vivo and in vitro studies

BACKGROUND

Arsenic exposure can cause fibrosis of organs including the liver, heart and lung. It was reported that TGF-β/Smad pathway played a crucial role in the process of fibrosis. However, the mechanism of arsenic-induced fibrosis through TGF-β/Smad signaling pathway has remained controversial.

OBJECTIVE

A systematic review and meta-analysis was performed to clarify the relationship between arsenic and TGF-β/Smad pathway, providing a theoretical basis of fibrosis process caused by arsenic.

METHODS

A meta-analysis was used to reveal a correlation between arsenic and fibrosis markers of TGF-β/Smad pathway, including 47 articles of both in vivo and in vitro studies. (Standardized Mean Difference) SMD was employed to compare and analyze the combined effects. When I2 > was 50%, random effect model was selected and subgroup analysis was used to explore the source of heterogeneity.

RESULTS

Arsenic exposure up-regulated the expression of TGF-β1, p-Smad2/3, α-SMA, Collagen1/3 and FN. The dose-response relationship showed that low dose (≤5 μmol/L) arsenic exposure up-regulated the expression of TGF-β1, whereas high doses had a tendency to down-regulate that of TGF-β1. Subgroup analysis showed that low or short-term arsenic exposure induced the expression of TGF-β1 and fibrosis markers.

CONCLUSION

The results indicated that arsenic activates the TGF-β/Smad pathway and induced fibrosis. The mechanism is related to the up-regulation of NADPH oxidase and ROS accumulation. However, high-dose arsenic exposure may inhibit this pathway.

Double-Sided Personality: Effects of Arsenic Trioxide on Inflammation

In 1992, arsenic trioxide (As₂O₃, ATO) was demonstrated to be an effective therapeutic agent against acute promyelocytic leukemia (APL), rekindling attention to ATO applications in U.S. Food and Drug Administration clinical trials for the treatment of cancers, such as leukemia, lymphomas, and solid tumors. ATO is a potent chemotherapeutic drug that can also be used to treat other diseases, such as autoimmune diseases, because it affects multiple pathways including apoptosis induction, differentiation stimulation, and proliferation inhibition. As inflammation is a critical component of disease progression, ATO is a feasible treatment option based on its ability to protect against inflammation. However, ATO is also a well-known carcinogen because of its pro-inflammatory effect. This review will focus on the double-sided effects of ATO on inflammation as well as the relevant mechanisms underlying these effects, aiming to provide a rational understanding of how ATO effects the immune system. We especially aim to provide a comprehensive overview of our current knowledge of how ATO influences inflammation.

The expressions of NGF and VEGF in the fracture tissues are closely associated with accelerated clavicle fracture healing in patients with traumatic brain injury

Background

Angiogenesis and bone formation are vital for fracture healing. Nerve growth factor (NGF) not only promotes neuronal survival but also enhances the proliferation and differentiation of osteoblasts. Vascular endothelial growth factor (VEGF) plays an important role in angiogenesis. However, the potential correlation of NGF and VEGF levels with fracture healing in patients with traumatic brain injury (TBI) remains unclear.

Methods

This study enrolled 22 patients with clavicle fracture and concomitant TBI (CFT group) and 25 patients with clavicle fracture alone (CF group). Serum NGF levels were measured with ELISA. The expressions of NGF, VEGF, and CD31 in callus tissues were measured with immunohistochemistry.

Results

The fracture healing time in CFT group (82.22±13.61 days) was significantly shorter than that in CF group (127±25.05 days; P<0.001). The expression of CD31, marker of blood vessels, in callus tissues of CFT group was higher compared with that of CF group. Serum NGF levels and the expression of NGF in callus tissues of CFT group were higher than those in CF group (P<0.01). The expressions of CD31, NGF, and VEGF are correlated with shorter fracture healing time.

Conclusion

The formation of blood vessels was increased in CFT group compared with CF group. NGF and VEGF levels were higher in CFT group than in CF group and correlated with shorter fracture healing time. Accelerated fracture healing in patients with TBI may be due to NGF- and VEGF-mediated angiogenesis at the fracture site.

Kaempferol inhibits the migration and invasion of rheumatoid arthritis fibroblast-like synoviocytes by blocking activation of the MAPK pathway

In rheumatoid arthritis (RA), fibroblast-like synoviocytes (FLSs) play an essential role in cartilage destruction. Aggressive migration and invasion by FLSs significantly affect RA pathology. Kaempferol has been shown to inhibit cancer cell migration and invasion. However, the effects of kaempferol on RA FLSs have not been investigated. Our study aimed to determine the effects of kaempferol on RA both in vitro and in vivo. In vitro, cell migration and invasion were measured using scratch assays and the Boyden chamber method, respectively. The cytoskeletal reorganization of RA FLSs was evaluated by immunofluorescence staining. Matrix metalloproteinase (MMP) levels were measured by real-time PCR, and protein expression levels were measured by western blotting. In vivo, the effects of kaempferol were evaluated in mice with CIA. The results showed that kaempferol reduced migration, invasion and MMP expression in RA FLSs. In addition, we demonstrated that kaempferol inhibited reorganization of the actin cytoskeleton during cell migration. Moreover, kaempferol dramatically suppressed tumor necrosis factor (TNF)-α-induced MAPK activation without affecting the expression of TNF-α receptors. We also demonstrated that kaempferol attenuated the severity of arthritis in mice with CIA. Taken together, these results suggested that kaempferol inhibits the migration and invasion of FLSs in RA by blocking MAPK pathway activation without affecting the expression of TNF-α receptors.