Expression Of Matrix Metallopeptidase Research Articles

Silencing of Epidermal Growth Factor-like Domain 8 Promotes Proliferation and Cancer Aggressiveness in Human Ovarian Cancer Cells by Activating ERK/MAPK Signaling Cascades.

Ovarian cancer (OC) is the second most common female reproductive cancer and the most lethal gynecological malignancy worldwide. Most human OCs are characterized by high rates of drug resistance and metastasis, leading to poor prognosis. Improving the outcomes of patients with relapsed and treatment-resistant OC remains a challenge. This study aimed to investigate the role of epidermal growth factor-like domain 8 (EGFL8) in human OC by examining the effects of siRNA-mediated EGFL8 knockdown on cancer progression. EGFL8 knockdown in human OC cells promoted aggressive traits associated with cancer progression, including enhanced proliferation, colony formation, migration, invasion, chemoresistance, and reduced apoptosis. Additionally, knockdown upregulated the expression of epithelial-mesenchymal transition (EMT) markers (Snail, Twist1, Zeb1, Zeb2, and vimentin) and cancer stem cell biomarkers (Oct4, Sox2, Nanog, KLF4, and ALDH1A1), and increased the expression of matrix metallopeptidases (MMP-2 and MMP-9), drug resistance genes (MDR1 and MRP1), and Notch1. Low EGFL8 expression also correlated with poor prognosis in human OC. Overall, this study provides crucial evidence that EGFL8 inhibits the proliferation and cancer aggressiveness of human OC cells by suppressing ERK/MAPK signaling. Therefore, EGFL8 may serve as a valuable prognostic biomarker and a potential target for developing novel human OC therapies.

Long-term hypoxic atmosphere enhances the stemness, immunoregulatory functions, and therapeutic application of human umbilical cord mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are usually cultured in a normoxic atmosphere (21%) in vitro, while the oxygen concentrations in human tissues and organs are 1% to 10% when the cells are transplanted in vivo. However, the impact of hypoxia on MSCs has not been deeply studied, especially its translational application. In the present study, we investigated the characterizations of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) in hypoxic (1%) and normoxic (21%) atmospheres with a long-term culture from primary to 30 generations, respectively. The comparison between both atmospheres systematically analyzed the biological functions of MSCs, mainly including stemness maintenance, immune regulation, and resistance to chondrocyte apoptosis, and studied their joint function and anti-inflammatory effects in osteoarthritis (OA) rats constructed by collagenase II. We observed that long-term hypoxic culture surpassed normoxic atmosphere during hUC-MSCs culture in respect of promoting proliferation, anti-tumorigenicity, maintaining normal karyotype and stemness, inhibiting senescence, and improving immunoregulatory function and the role of anti-apoptosis in chondrocytes. Furthermore, we demonstrated that the transplantation of long-term hypoxic hUC-MSCs (Hy-MSCs) had a better therapeutic effect on OA rats compared with the hUC-MSCs cultured in the normoxic atmosphere (No-MSCs) in terms of the improved function and swelling recovery in the joints, and substantially inhibited the secretion of pro-inflammatory factors, which effectively alleviated cartilage damage by reducing the expression of matrix metallopeptidase 13 (MMP-13). Our results demonstrate that Hy-MSCs possess immense potential for clinical applications via promoting stemness maintenance and enhancing immunoregulatory function.

Attenuating Cartilage Degeneration in a Low Mechanical Compression Rat Model Through Intra-Articular Injections of Allogeneic Bone Marrow-Derived Mesenchymal Stem Cells.

Mechanical stimulation significantly contributes to posttraumatic osteoarthritis (PTOA), a condition that impedes patient recovery following intra-articular injury. Effective treatment options for compression-induced injuries are limited. Bone marrow-derived mesenchymal stem cell (BMSC) implantation has emerged as a potential therapeutic breakthrough for joint diseases. The aim of this study was to attenuate the progression of PTOA induced by cyclic loading and demonstrate the potential effectiveness of BMSCs in a rat model of low mechanical compression. Using a rat model of compression-induced articular cartilage injury, assessments were conducted 2, 4, and 8 weeks after cyclic compressive loading. The expression of matrix metallopeptidase 13, transforming growth factor-beta 3 (TGF-β3), insulin-like growth factor 1 (IGF-1), and cleaved caspase-3 was evaluated through immunohistochemistry to investigate the mechanistic aspects underlying the prevention of compression-induced injury following BMSCs treatment. Intra-articular injections of BMSCs significantly improved scores in the OARSI (Osteoarthritis Research Society International) Osteoarthritis Cartilage Histopathology Assessment System and Histological-Histochemical Grading System. This treatment showed positive outcomes in maintaining high relative cell density and reducing proteoglycan loss after cyclic compression-induced injury. The expression patterns of IGF-1 and TGF-β3 provide valuable insights into the presence and distribution of these growth factors in healthy and injured cartilage. These findings highlight the efficacy of BMSCs treatment in attenuating the advancement of compression-induced injuries, albeit within a limited timeframe.

RIP1 inhibition reduces chondrocyte apoptosis through downregulating nuclear factor-kappa B signaling in a mouse osteoarthritis model.

Excessive chondrocyte death is a critical player in the process of osteoarthritis (OA). The present study was aimed to study the role of receptor-interacting serine/threonine kinase (RIP) 1-mediated signaling for programmed cell death in OA. In the present study, RIP1 protein expression was evaluated in mouse OA cartilage and cultured primary murine chondrocytes exposed to tumor necrosis factor-alpha (TNF-α). Protein expression involved in necroptosis and apoptosis and chondrocyte-derived extracellular matrix were examined. Inhibition of RIP1 was conducted using the RNAi technique and pharmacological inhibition. Western blot, immunohistochemistry, and immunofluorescence examination were applied. The protein presence of RIP1, but not RIP3, was increased in the mouse OA tissue and cultured chondrocytes exposed to TNF-α. Knockdown of RIP1 increased protein expression of collagen II and sex-determining region Y-box transcription factor 9, and reduced protein expression of matrix metallopeptidases 13 and a disintegrin and metalloproteinase with thrombospondin motifs 5. Inhibition of RIP1 reduced the phosphorylated NF-κB signals, decreased cell apoptosis, and restored extracellular matrix expression in cultured chondrocytes. Both RNAi and pharmacological inhibition of RIP1 decelerated the progress of OA in mice. RIP1 regulates chondrocyte apoptosis through NF-κB signaling. Inhibition of RIP1 provides a novel therapeutic approach for OA therapy.

Curcumin Inhibits Vasculogenic Mimicry via Regulating ETS-1 in Renal Cell Carcinoma.

Metastatic renal cell carcinoma (RCC) poses a huge challenge once it has become resistant to targeted therapy. Vasculogenic mimicry (VM) is a novel blood supply system formed by tumor cells that can circumvent molecular targeted therapies. As one of the herbal remedies, curcumin has been demonstrated to play antineoplastic effects in many different types of human cancers; however, its function and mechanism of targeting VM in RCC remains unknown. Here, in the work, we explored the role of curcumin and its molecular mechanism in the regulation of VM formation in RCC. RNA-sequencing analysis, immunoblotting, and immunohistochemistry were used to detect E Twenty Six-1(ETS-1), vascular endothelial Cadherin (VE-Cadherin), and matrix metallopeptidase 9 (MMP9) expressions in RCC cells and tissues. RNA sequencing was used to screen the differential expressed genes. Plasmid transfections were used to transiently knock down or overexpress ETS-1. VM formation was determined by tube formation assay and animal experiments. CD31-PAS double staining was used to label the VM channels in patients and xenograft samples. Our results demonstrated that VM was positively correlated with RCC grades and stages using clinical patient samples. Curcumin inhibited VM formation in dose and time-dependent manner in vitro. Using RNA-sequencing analysis, we discovered ETS-1 as a potential transcriptional factor regulating VM formation. Knocking down or overexpression of ETS-1 decreased or increased the VM formation, respectively and regulated the expression of VE-Cadherin and MMP9. Curcumin could inhibit VM formation by suppressing ETS-1, VE-Cadherin, and MMP9 expression both in vitro and in vivo. Our finding might indicate that curcumin could inhibit VM by regulating ETS-1, VE-Cadherin, and MMP9 expression in RCC cell lines. Curcumin could be considered as a potential anti-cancer compound by inhibiting VM in RCC progression.

SIRT2 Alleviates Inflammatory Response, Apoptosis, and ECM Degradation in Osteoarthritic Chondrocytes by Stabilizing PCK1.

It has been reported that Sirtuin 2 (SIRT2) prevents phosphoenolpyruvate carboxykinase 1 (PCK1) degradation, which can be involved in aging-induced osteoarthritis (OA), but the molecular mechanism of SIRT2/PCK1 in chondrocytes has not been clarified. Therefore, this study aims to explore the mechanism of SIRT2/PCK1 in chondrocyte inflammation. To establish the OA model in vitro, chondrocytes cultured with interleukin-1β (IL-1β, 10 ng/mL) and manipulation of SIRT2 and PCK1 expression in the constructed cells to elucidate the interaction between the two genes. 1,9-Dimethyl-Methylene Blue (DMMB) was used to detect cellular glycosaminoglycan (GAG) content. Inflammatory factor levels were assessed using Enzyme-linked Immunosorbent Assay (ELISA). Apoptosis was detected by osmotic dye. The expression of B-cell lymphoma-2 (Bcl-2), Bcl-2 Associated X (Bax), Wnt Family Member 1 (Wnt1), catenin Beta 1 (β-catenin), Aggrecan, Collagen II, matrix metallopeptidase 13 (MMP-13) proteins in cells were analyzed using Western blot. PCK1 gained lower expressions in OA cell models. Overexpression of PCK1 or SIRT2 in the IL-1β chondrocyte model of inflammation promoted GAG content, inhibited apoptosis and Wnt/β-catenin protein expression, and lowered the levels of inflammatory factors. PCK1 silencing was proved to have the opposite effect. SIRT2 overexpression rescued the increased inflammation, MMP-13 expression, and apoptosis and the decreased Aggrecan and Collagen II expression caused by PCK1 silencing. PCK1 silencing also reversed the positive effects of SIRT2 overexpression on chondrocytes. SIRT2 inhibits articular chondrocyte extracellular matrix (ECM) degradation, inflammatory factor expression, and apoptosis via PCK1.

Actinidia chinensis polysaccharide interferes with the epithelial-mesenchymal transition of gastric cancer by regulating the nuclear transcription factor-κB pathway to inhibit invasion and metastasis.

To investigate the mechanisms of the effect of Actinidia chinensis polysaccharide (ACPS) on the invasion and metastasis of gastric cancer cells. BGC-823-Luc gastric cancer cells stably transfected with a luciferase gene were used to establish an insitutransplanted tumor mouse model. A live mouse imaging system was used to observe tumor growth, and hematoxylin and eosin staining was applied to analyze tissue histopathology. Transwell and scratch wound assays were performed to examine the invasive and migratory ability of BGC-823 cells. Immunofluorescence, confocal microscopy, immunohistochemistry, and Western blot assays were used to analyze the expressions of the nuclear transcription factor-κB (NF-κB) signaling pathway and epithelial-mesenchymal transition (EMT)-related proteins. ACPS significantly inhibited the growth of subcutaneously transplanted BGC-823-Luc gastric cancer tumors in nude mice and reduced inflammatory cell infiltration in tumor tissues. ACPS inhibited Epidermal Growth Factor-induced invasion, migration, and morphological changes in the cytoskeleton of BGC-823 cells. ACPS inhibited gastric cancer EMT and decreased the expression of matrix metallopeptidase 9, N-cadherin and p-NF-κB p65 in transplanted tumor tissues. ACPS inhibited the expression of matrix metalloproteinases and vascular adhesion factors in BGC-823 cells, promoted p65-NF-κB nuclear translocation, and regulated proteins associated with the NF-κB p65 pathway. ACPS inhibited gastric cancer invasion and metastasis both in vivo and in vitro, which evidenced the inhibition of gastric cancer EMT viaregulating the NF-κB inflammatory pathway.

Effect of Linggui Zhugan Decoction on myocardial fibrosis and Lats1/Yap signaling pathway in mice after myocardial infraction

This study aims to investigate the effects of Linggui Zhugan Decoction(LGZGD) on myocardial fibrosis(MF) and the Lats1/Yap signaling pathway in mice after myocardial infarction(MI), exploring its role and mechanism in inhibiting MF. The MI-induced ischemic mouse model was established by left anterior descending coronary artery ligation, followed by continuous intervention for six weeks. Doppler ultrasound imaging-system of small animals was used to detect left ventricular ejection fraction(LVEF), left ventricular fractional shortening(LVFS), left ventricular internal diameter at end-systole(LVIDs), and left ventricular internal diameter at end-diastole(LVIDd). Pathological changes in myocardial tissue were observed by HE and Masson staining. Serum levels of creatine kinase isoenzyme MB(CK-MB) and lactate dehydrogenase(LDH) were detected by using ELISA. Myocardial tissue mRNA levels of Lats1, Yap, and connective tissue growth factor(CTGF) were determined by RT-qPCR. Protein expression of alpha-smooth muscle actin(α-SMA), collagen Ⅰ(Col Ⅰ), collagen Ⅲ(Col Ⅲ), tissue inhibitor of metal protease 1(TIMP1), matrix metallopeptidase 2(MMP2), Yap, p-Yap, and n-Yap was determined by Western blot. Compared with the sham group, the model group showed significantly decreased LVEF and LVFS levels, increased LVIDd and LVIDs levels(P<0.01), disordered arrangement of myocardial cells, partial fracture of myocardial fibers, and massive deposition of collagen fibers. Moreover, serum levels of CK-MB and LDH were significantly increased(P<0.01), while myocardial tissue mRNA levels of Lats1 were significantly decreased(P<0.01), and mRNA levels of Yap and CTGF were significantly increased(P<0.01). Protein expression of α-SMA, Col Ⅰ, Col Ⅲ, MMP2, Yap, and n-Yap was significantly increased(P<0.01), while protein expression of Lats1, TIMP1, p-Yap, and the ratio of p-Yap/Yap were significantly decreased(P<0.01). Compared with the model group, after intervention with LGZGD(9.36 g·kg~(-1)), mice showed significantly increased LVEF and LVFS levels, decreased LVIDd and LVIDs levels(P<0.01), more orderly arrangement of myocardial cells, significantly reduced myocardial fiber fracture and collagen fiber deposition. Serum levels of CK-MB and LDH were significantly decreased(P<0.01), while myocardial tissue mRNA levels of Lats1 were significantly increased(P<0.01), and mRNA levels of Yap and CTGF were significantly decreased(P<0.01). Protein expression of α-SMA, Col Ⅰ, Col Ⅲ, MMP2, Yap, and n-Yap was significantly decreased(P<0.01), while protein expression of Lats1, TIMP1, p-Yap, and the ratio of p-Yap/Yap were significantly increased(P<0.01). LGZGD can inhibit MF in mice after MI and improve mouse cardiac function, which is closely related to the activation of the Lats1/Yap signaling pathway.

Abstract Tu102: The Role of the β IV -spectrin/STAT3 Complex in Regulating Ischemic Cardiac Remodeling

Adverse fibrotic remodeling contributes to high morbidity and mortality in patients following myocardial infarction (MI). The healing process after MI requires necrotic tissue to be cleared and replaced with fibrosis, which is driven by the coordinated effort of several distinct cardiac cell populations, including macrophages and cardiac fibroblasts (CFs). While previous studies have focused on identifying the stimuli that drives fibrotic remodeling in the infarcted myocardium, the contribution of specific cell populations to the signaling cascade and the manner of how these communication networks are tuned in response to chronic stress remains unclear. Prior work has identified a role for the cytoskeletal protein, β IV -spectrin, in coordinating the activity of the transcription factor, STAT3, with implications for CF activation and profibrotic signaling. Specifically, it was found that mice expressing truncated β IV -spectrin ( qv 3J ) are resistant to cardiac fibrosis in the setting of chronic pressure overload, with maintained β IV -spectrin expression and STAT3 localization/activity in CFs. Further, β IV -spectrin deficiency causes increased secretion of profibrotic and proinflammatory factors, including matrix metallopeptidases (MMPs). Therefore, we hypothesized that stress-induced loss of β IV -spectrin and subsequent dysregulation of STAT3 signaling in CFs proximal to the infarct promotes fibroblast activation, an important first step in repairing the infarct region. In this study, we subjected WT and qv 3J mice to permanent ligation of the left anterior descending artery and assessed cardiac function and survival through 28 days. A subset of mice were sacrificed at 7 days for histology, qPCR, and flow cytometry. Compared to WT, qv 3J mice showed a significant decrease in 28-day survival with increased mortality in the first week post-MI. Autopsy identified increased incidence of cardiac rupture in qv 3J animals. Immunohistochemistry revealed impaired scar formation at 7 days post-MI in qv 3J compared to WT. Quantitative PCR showed altered expression of matrix metallopeptidases (MMPs 3, 8, 9, and 14) in the qv 3J hearts at day 7. MMP activity was assessed in whole heart lysates using gelatin-zymography. Collagen uptake was assessed in CFs and bone marrow-derived macrophages isolated from WT and qv 3J mice. Our work identifies a novel role of the spectrin-based pathway in facilitating fibrotic remodeling in response to ischemic stress.

Silencing SPP1 in M2 macrophages inhibits the progression of castration-resistant prostate cancer via the MMP9/TGFβ1 axis.

M2 macrophages can promote the progression of castration-resistant prostate cancer (CRPC), but the specific mechanism is still unclear. Therefore, we are preliminarily exploring the molecular mechanism by which M2 macrophages regulate the progression of CRPC. The genes positively correlated with CRPC and with the most significant differences in the GEO32269 dataset were obtained. Database and immunofluorescence experiments were used to validate the localization of secreted phosphoprotein 1 (SPP1) in localized prostate cancer (PCa), hormone-sensitive prostate cancer (HSPC), and CRPC tumor tissues. The function of SPP1 in M2 macrophages was verified through cell scratch, Transwell, and an orthotopic PCa model. PCa database and Western blot were used to verify the relationship between SPP1 and matrix metallopeptidase 9 (MMP9), as well as the ability of MMP9 in M2 macrophages to promote epithelial-mesenchymal transition (EMT) in PCa cells. The primary localization of SPP1 in prostate and CRPC tissues is in macrophages. Silencing SPP1 expression in M2 macrophages promotes their polarization towards the M1 phenotype and significantly inhibits the malignant progression of PCa in vitro and in vivo. SPP1 promotes the expression of MMP9 through the PI3K/AKT signaling pathway in M2 macrophages. Furthermore, MMP9 enhances the EMT and migratory capabilities of PC3 cells by activating the TGFβ signaling pathway. We have found that the high expression of SPP1 in M2 macrophages promotes the progression of CRPC through cell-cell interactions. These findings can contribute to the development of novel therapeutic approaches for combating this deadly disease.

Phagocytosis of aggrecan-positive perineuronal nets surrounding motor neurons by reactive microglia expressing MMP-9 in TDP-43Q331K ALS model mice

Perineuronal nets (PNNs) are extracellular matrix structures that surround excitable neurons and their proximal dendrites. PNNs play an important role in neuroprotection against oxidative stress. Oxidative stress within motor neurons can act as a trigger for neuronal death, and this has been implicated in motor neuron degeneration in amyotrophic lateral sclerosis (ALS). We therefore characterised PNNs around alpha motor neurons and the possible contributing cellular factors in the mutant TDP-43Q331K transgenic mouse, a slow onset ALS mouse model. PNNs around alpha motor neurons showed significant loss at mid-stage disease in TDP-43Q331K mice compared to wild type strain control mice. PNN loss coincided with an increased expression of matrix metallopeptidase-9 (MMP-9), an endopeptidase known to cleave PNNs, within the ventral horn. During mid-stage disease, increased numbers of microglia and astrocytes expressing MMP-9 were present in the ventral horn of TDP-43Q331K mice. In addition, TDP-43Q331K mice showed increased levels of aggrecan, a PNN component, in the ventral horn by microglia and astrocytes during this period. Elevated aggrecan levels within glia were accompanied by an increase in fractalkine expression, a chemotaxic protein responsible for the recruitment of microglia, in alpha motor neurons of onset and mid-stage TDP-43Q331K mice. Following PNN loss, alpha motor neurons in mid-stage TDP-43Q331K mice showed increased 3-nitrotyrosine expression, an indicator of protein oxidation. Together, our observations along with previous PNN research provide suggests a possible model whereby microglia and astrocytes expressing MMP-9 degrade PNNs surrounding alpha motor neurons in the TDP-43Q331K mouse. This loss of nets may expose alpha-motor neurons to oxidative damage leading to degeneration of the alpha motor neurons in the TDP-43Q331K ALS mouse model.

Ficus pumila fruit polysaccharide attenuate ovalbumin-induced allergic asthma in mice associated with changes in microbiota involving the lung-intestinal axis

Allergic asthma accounts for more than 50 percent of adult asthma in life. Glucocorticoids and leukotriene receptor antagonists are commonly used to treat asthma, but these drugs not only have high side effects but also cannot cure the disease. In contrast, natural active ingredients are relatively safe to the organism and show great potential for improving the organism. Polysaccharides, as the main active ingredient in aqueous extract, may be equally beneficial for biological activity. The aim of this study is to investigate the alleviating effect and mechanism of action of Ficus pumila fruit polysaccharide (FPP) and aqueous extract of Ficus pumila fruit (FPW) on mice with allergic asthma. The results showed that FPP and FPW could regulate the secretion of the cytokines IL-4, IL-5, IL-13, and IFN-γ. FPP and FPW also reduced the inflammation, mucus secretion, and collagen deposition in mouse lung tissue, and down-regulated the expression of matrix metallopeptidase-9 (MMP-9), tissue inhibitor of metalloproteinases-1 (TIMP-1), and α-smooth muscle actin (α-SMA) proteins. In addition, FPP and FPW modulated the intestinal microbiota by augmenting the alpha diversity and adjusting the taxonomic composition at the phylum and family levels, thereby ensured the sustenance of regular physiological processes in the body. This study demonstrated that FPP and FPW may attenuate asthma by inducing beneficial microbiota in the gut-lung axis and provide an effective basis for the future clinical treatment of allergic asthma with Ficus pumila and the development and utilization of new anti-asthma drugs.

Alendronate treatment rescues the effects of compressive loading of TMJ in osteogenesis imperfecta mice

BackgroundOsteogenesis imperfecta (OI) is a genetic disorder of connective tissue caused by mutations associated with type I collagen, which results in defective extracellular matrix in temporomandibular joint (TMJ) cartilage and subchondral bone. TMJ is a fibrocartilaginous joint expressing type I collagen both in the cartilage and the subchondral bone. In the present study the effects of alendronate and altered loading of the TMJ was analyzed both in male and female OI mice.Materials and methodsForty-eight, 10-weeks-old male and female OI mice were divided into 3 groups: (1) Control group: unloaded group, (2) Saline + Loaded: Saline was injected for 2 weeks and then TMJ of mice was loaded for 5 days, (3) alendronate + loaded: alendronate was injected for 2 weeks and then TMJ of mice was loaded for 5 days. Mice in all the groups were euthanized 24-h after the final loading.ResultsAlendronate pretreatment led to significant increase in bone volume and tissue density. Histomorphometrically, alendronate treatment led to increase in mineralization, cartilage thickness and proteoglycan distribution. Increased mineralization paralleled decreased osteoclastic activity. Our immunohistochemistry revealed decreased expression of matrix metallopeptidase 13 and ADAM metallopeptidase with thrombospondin type 1 motif 5.ConclusionThe findings of this research support that alendronate prevented the detrimental effects of loading on the extracellular matrix of the TMJ cartilage and subchondral bone.

Arnicolide D Inhibits Oxidative Stress-induced Breast Cancer Cell Growth and Invasion through Apoptosis, Ferroptosis, and Parthanatos.

Breast cancer is the most common malignant tumor in women, and its pathogenesis is very complicated. More and more studies have found that Traditional Chinese Medicine plays an important role in tumor prevention. To investigate the mechanism of arnicolide D isolated from Centipeda minima in breast cancer. Cell Counting Kit-8 (CCK-8), western blot, RT-qPCR, ELISA, flow cytometry, and Transwell were used to detect the effect of arnicolide D on the biological function of breast cancer cells. Arnicolide D promoted reactive oxygen species (ROS) production and induced a decrease in mitochondrial membrane potential in breast cancer cells, thereby inhibiting cell viability and increasing lactate dehydrogenase (LDH) release. Arnicolide D activated the classical apoptosis pathway to induce cell apoptosis; it significantly promoted PARP-1 expression, enhanced the nuclear translocation of apoptosis-inducing factor (AIF), and reduced the expression of AIF in mitochondria, indicating that it can induce the occurrence of parthanatos in a ROS dependent manner. In addition, arnicolide D down-regulated glutathione peroxidase 4 (GPX4) expression and increased the accumulation of Fe2+ and malondialdehyde (MDA), thereby activating ferroptosis. Apoptosis inhibitor, ferroptosis inhibitor, PARP inhibitor, PARP-1 siRNA, AIF siRNA and GPX4 overexpression vector significantly attenuated the inhibitory effect of arnicolide D on cell viability and reduced LDH release, which indicates that arnicolide D inhibits breast cancer cell growth by inducing apoptosis, parthanatos and ferroptosis. Arnicolide D also reduced breast cancer cell invasion and inhibited the expression of matrix metallopeptidase (MMP)-2 and MMP-9. Arnicolide D can activate a variety of cell death modes by inducing oxidative stress, thereby inhibiting the growth and invasion of breast cancer cells, indicating that arnicolide D has a good anti-tumor effect.

Lnc-216 regulates the miR-143-5p /MMP2 signaling axis aggravates retinal endothelial cell dysfunction.

Diabetic retinopathy (DR) is a serious retinal vascular disease that affects many individuals in their prime working years. The present research aimed at whether and how LOC681216 (LNC-216) is involved in retinal vascular dysfunction under diabetic conditions. Rat retinal microvascular endothelial cells (RRMECs) treated with high glucose (HG) were used for functional analysis. Gene expression analysis was conducted using the Clariom D Affymetrix platform. The wound healing, transwell, and vascular tube formation assays were used to identify the migration, invasion, and tube formation capability of RRMECs. The dual-luciferase reporter confirmed the binding interaction between miR-143-5p and LNC-216 or matrix metallopeptidase 2 (MMP2). Lnc-216 was upregulated in RRMECs treated with HG. Lnc-216 knockdown markedly suppressed the tube formation, cell migration, and wound healing of cultured RRMECs under HG conditions. Mechanistically, Lnc-216 acted as a miR-143-5p sponge to affect the biological activity of miR-143-5p, which led to increased expression of matrix metallopeptidase 2 (MMP2). Lnc-216 attenuates diabetic retinal vascular dysfunction through the miR-143-5p/MMP2 axis, providing a potential therapeutic strategy for DR.

Targeting nerve growth factor-mediated osteosarcoma metastasis: mechanistic insights and therapeutic opportunities using larotrectinib

Osteosarcoma (OS) therapy presents numerous challenges, due largely to a low survival rate following metastasis onset. Nerve growth factor (NGF) has been implicated in the metastasis and progression of various cancers; however, the mechanism by which NGF promotes metastasis in osteosarcoma has yet to be elucidated. This study investigated the influence of NGF on the migration and metastasis of osteosarcoma patients (88 cases) as well as the underlying molecular mechanisms, based on RNA-sequencing and gene expression data from a public database (TARGET-OS). In osteosarcoma patients, the expression of NGF was significantly higher than that of other growth factors. This observation was confirmed in bone tissue arrays from 91 osteosarcoma patients, in which the expression levels of NGF and matrix metallopeptidase-2 (MMP-2) protein were significantly higher than in normal bone, and strongly correlated with tumor stage. In summary, NGF is positively correlated with MMP-2 in human osteosarcoma tissue and NGF promotes osteosarcoma cell metastasis by upregulating MMP-2 expression. In cellular experiments using human osteosarcoma cells (143B and MG63), NGF upregulated MMP-2 expression and promoted wound healing, cell migration, and cell invasion. Pre-treatment with MEK and ERK inhibitors or siRNA attenuated the effects of NGF on cell migration and invasion. Stimulation with NGF was shown to promote phosphorylation along the MEK/ERK signaling pathway and decrease the expression of microRNA-92a-1-5p (miR-92a-1-5p). In in vivo experiments involving an orthotopic mouse model, the overexpression of NGF enhanced the effects of NGF on lung metastasis. Note that larotrectinib (a tropomyosin kinase receptor) strongly inhibited the effect of NGF on lung metastasis. In conclusion, it appears that NGF promotes MMP-2-dependent cell migration by inhibiting the effects of miR-92a-1-5p via the MEK/ERK signaling cascade. Larotrectinib emerged as a potential drug for the treatment of NGF-mediated metastasis in osteosarcoma.

Perineuronal nets are phagocytosed by MMP-9 expressing microglia and astrocytes in the SOD1G93A ALS mouse model.

Perineuronal nets (PNNs) are an extracellular matrix structure that encases excitable neurons. PNNs play a role in neuroprotection against oxidative stress. Oxidative stress within motor neurons can trigger neuronal death, which has been implicated in amyotrophic lateral sclerosis (ALS). We investigated the spatio-temporal timeline of PNN breakdown and the contributing cellular factors in the SOD1G93A strain, a fast-onset ALS mouse model. This was conducted at the presymptomatic (P30), onset (P70), mid-stage (P130), and end-stage disease (P150) using immunofluorescent microscopy, as this characterisation has not been conducted in the SOD1G93A strain. We observed a significant breakdown of PNNs around α-motor neurons in the ventral horn of onset and mid-stage disease SOD1G93A mice compared with wild-type controls. This was observed with increased numbers of microglia expressing matrix metallopeptidase-9 (MMP-9), an endopeptidase that degrades PNNs. Microglia also engulfed PNN components in the SOD1G93A mouse. Further increases in microglia and astrocyte number, MMP-9 expression, and engulfment of PNN components by glia were observed in mid-stage SOD1G93A mice. This was observed with increased expression of fractalkine, a signal for microglia engulfment, within α-motor neurons of SOD1G93A mice. Following PNN breakdown, α-motor neurons of onset and mid-stage SOD1G93A mice showed increased expression of 3-nitrotyrosine, a marker for protein oxidation, which could render them vulnerable to death. Our observations suggest that increased numbers of MMP-9 expressing glia and their subsequent engulfment of PNNs around α-motor neurons render these neurons sensitive to oxidative damage and eventual death in the SOD1G93A ALS model mouse.

MicroRNA 429 regulates MMPs expression by modulating TIMP2 expression in colon cancer cells and inflammatory colitis.

In a previous study, we found that the expression of microRNA 429 (MIR429) was decreased in dextran sodium sulfate (DSS)-induced mouse colitis tissues. In this study, we aimed to investigate the interaction of MIR429 with TIMP metallopeptidase inhibitor 2 (TIMP2), one of its candidate target genes, in human colorectal cancer (CRC) cells and DSS-induced mouse colitis tissues. A luciferase reporter system was used to confirm the effect of MIR429 on TIMP2 expression. The expression levels of MIR429 and target genes in cells or tissues were evaluated through quantitative RT-PCR, western blotting, or immunohistochemistry. We found that the expression level of MIR429 was downregulated in human CRC tissues, and also showed that TIMP2 is a direct target gene of MIR429 in CRC cell lines. Furthermore, MIR429 regulate TIMP2-mediated matrix metallopeptidases (MMPs) expression in CRC cells. We also generated cell lines stably expressing MIR429 in CRC cell lines and showed that MIR429 regulates the expression of MMPs by mediating TIMP2 expression. In addition to human CRC tissues, we found that TIMP2 was highly expressed in mouse colitis tissues and human ulcerative colitis (UC) tissues. Our findings suggest that the expression of endogenous MIR429 was reduced in human CRC tissues and colitis, leading to upregulation of its target gene TIMP2. The upregulation of TIMP2 by decreased MIR429 expression in CRC tissues and inflamed tissues suggests that it may affect extracellular matrix (ECM) remodeling through downregulation of MMPs. Therefore, MIR429 may have therapeutic value for human CRC and colitis.

BAG3 promotes proliferation and migration of arterial smooth muscle cells by regulating STAT3 phosphorylation in diabetic vascular remodeling

BackgroundDiabetic vascular remodeling is the most important pathological basis of diabetic cardiovascular complications. The accumulation of advanced glycation end products (AGEs) caused by elevated blood glucose promotes the proliferation and migration of vascular smooth muscle cells (VSMCs), leading to arterial wall thickening and ultimately vascular remodeling. Therefore, the excessive proliferation and migration of VSMCs is considered as an important therapeutic target for vascular remodeling in diabetes mellitus. However, due to the lack of breakthrough in experiments, there is currently no effective treatment for the excessive proliferation and migration of VSMCs in diabetic patients. Bcl-2-associated athanogene 3 (BAG3) protein is a multifunctional protein highly expressed in skeletal muscle and myocardium. Previous research has confirmed that BAG3 can not only regulate cell survival and apoptosis, but also affect cell proliferation and migration. Since the excessive proliferation and migration of VSMCs is an important pathogenesis of vascular remodeling in diabetes, the role of BAG3 in the excessive proliferation and migration of VSMCs and its molecular mechanism deserve further investigation.MethodsIn this study, BAG3 gene was manipulated in smooth muscle to acquire SM22αCre; BAG3FL/FL mice and streptozotocin (STZ) was used to simulate diabetes. Expression of proteins and aortic thickness of mice were detected by immunofluorescence, ultrasound and hematoxylin-eosin (HE) staining. Using human aorta smooth muscle cell line (HASMC), cell viability was measured by CCK-8 and proliferation was measured by colony formation experiment. Migration was detected by transwell, scratch experiments and Phalloidin staining. Western Blot was used to detect protein expression and Co-Immunoprecipitation (Co-IP) was used to detect protein interaction.ResultsIn diabetic vascular remodeling, AGEs could promote the interaction between BAG3 and signal transducer and activator of transcription 3 (STAT3), leading to the enhanced interaction between STAT3 and Janus kinase 2 (JAK2) and reduced interaction between STAT3 and extracellular signal-regulated kinase 1/2 (ERK1/2), resulting in accumulated p-STAT3(705) and reduced p-STAT3(727). Subsequently, the expression of matrix metallopeptidase 2 (MMP2) is upregulated, thus promoting the migration of VSMCs.ConclusionsBAG3 upregulates the expression of MMP2 by increasing p-STAT3(705) and decreasing p-STAT3(727) levels, thereby promoting vascular remodeling in diabetes. This provides a new orientation for the prevention and treatment of diabetic vascular remodeling.

Glioblastoma U-87 cell electrotaxis is hindered by doxycycline with a concomitant reduction in the matrix metallopeptidase-9 expression

Electric fields (EF) play an essential role in cancer cell migration. Numerous cancer cell types exhibit electrotaxis under direct current electric fields (dcEF) of physiological electric field strength (EFs). This study investigated the effects of doxycycline on the electrotactic responses of U87 cells. After EF stimulation, U87 cells migrated toward the cathode, whereas doxycycline-treated U87 cells exhibited enhanced cell mobility but hindered cathodal migration. We further investigated the expression of the metastasis-correlated proteins matrix metallopeptidase-2 (MMP-2) and MMP-9 in U87 cells. The levels of MMP-2 in the cells were not altered under EF or doxycycline stimulation. In contrast, the EF stimulation greatly enhanced the levels of MMP-9 and then repressed in doxycycline-cotreated cells, accompanied by reduced cathodal migration. Our results demonstrated that an antibiotic at a non-toxic concentration could suppress the enhanced cell migration accelerated by EF of physiological strength. This finding may be applied as an anti-metastatic treatment for cancers.