MMP-9 Protein Expression Research Articles

A new animal model of lumbar disc degeneration in rabbits

BACKGROUND CONTEXTThere are many models of lumbar disc degeneration, but mechanical stress-induced lumbar disc degeneration is rare. Here we propose a mechanical stress-induced lumbar disc degeneration model to better understand the molecular mechanism of lumbar disc degeneration under stress stimulation. PURPOSETo design a new model of lumbar disc degeneration under mechanical stress. STUDY DESIGNThe anatomic approach of the oblique lateral approach to lumbar fusion surgery was used to design a longitudinal compression device across the vertebral body of the rabbit to impose longitudinal load on the lumbar disc. METHODSNew Zealand white rabbits (n=30) were used. Screws were used to cross the rabbits’ lumbar vertebral bodies, and both sides of the screws were pressurized. Continuous compression was then performed for 28 days. Adjacent unpressurized lumbar discs serve as controls for pressurized lumbar discs. At 28 days after surgery, micro-computed tomography (CT) and magnetic resonance imaging (MRI) were performed on the rabbits’ lumbar discs. After the imaging examination, lumbar disc samples were removed, Safranin-O fast green and immunofluorescence was performed to detect the expression level of intervertebral disc degeneration-related proteins. RESULTSThe CT results showed that the disc height did not decrease significantly after mechanical loading. The MRI results showed that the signals in the pressurized disc decreased 28 days after loading. The results of Safranin-O fast green showed that the cartilage component of the intervertebral disc after mechanical compression was significantly reduced. The immunofluorescence results showed that the expression of ADAMTS5 and MMP13 protein in the nucleus pulposus of the intervertebral disc after mechanical compression increased, while the expression of SOX9 decreased, and the difference was statistically significant. Aggrecan's protein expression decreased, but was not statistically significant. CONCLUSIONSThis study designed a reliable model of disc degeneration in rabbits. It is more likely to mimic disc compression in the human body. CLINICAL SIGNIFICANCEThis animal model can be used as a basic model to study the molecular physiological mechanisms of discogenic low back pain.

Exploring the Mechanisms of the Huangqin Qingfei Decoction in Pneumonia Treatment for Lipopolysaccharide-Induced Mouse Model: A Network Pharmacology Analysis and Experimental Validation

Objective: In this study, a network pharmacological approach, and in vivo validation experiments were used to screen the active components of the Huangqin Qingfei decoction (HQFD) for their therapeutic efficacy in pneumonia. Methods: The active ingredients and targets of the HQFD were retrieved from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform, while pneumonia-related targets were obtained from GeneCards, Online Mendelian Inheritance in Man, and the Therapeutic Target Database. A protein–protein interaction network was constructed to identify core targets, followed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses using Metascape. A lipopolysaccharide-induced pneumonia mouse model was established, and verification of the main targets predicted by network pharmacology and therapeutic efficacy assessment was conducted using pathological staining, Western blot, and polymerase chain reaction. Results: We identified 51 active components in the HQFD that primarily affected pneumonia-related targets AKT1, PTGS2, MAPK14, and MMP9. The outcomes of the pathway enrichment analyses conducted by the KEGG and the GO demonstrated that the HQFD regulates genes associated with pathways in cancer, the lipid and atherosclerosis, as well as the AGE-RAGE signaling pathway in diabetic complications. Experiments on animals demonstrated that the AKT1, PTGS2, MAPK14, and MMP9 mRNA expression and p-AKT, p-P38, PTGS2, and MMP9 protein expression in lung tissues were significantly upregulated in the model group when compared to the control group. AKT1, PTGS2, MAPK14, MMP9 mRNA expression, and p-AKT, p-P38, PTGS2, and MMP9 protein expression were all lower in the HQFD groups in contrast to the model group. Conclusions: The effects of HQFD on pneumonia can be attributed to its active ingredients, including beta-sitosterol, wogonin, and quercetin. The mechanism involves multiple targets and pathways, including the PI3K-AKT signaling pathway, MAPK signaling pathway, and NF-kappa B signaling pathway, and modulation of AKT, PTGS2, MAPK14, and MMP9 expression. The HQFD reduces inflammatory damage and pneumonia symptoms via these mechanisms.

Inhibiting Effect of Cationic Procyanidin Nanoparticles on Drug-Resistant Oral Squamous Cell Carcinoma Cell Lines

Background: Multidrug resistance (MDR) is one of the primary causes of tumor chemotherapy failure. Therefore, it is essential to uncover new drug treatment protocols. In the current study, employing chitosan (CS) and sodium tripolyphosphate (TPP) as carriers and cross-linking agents, the proanthocyanidins (PHL)/poly (lactic-co-glycolic acid) (PLGA) were encapsulated by emulsion solvent evaporation, through which the cationic CS-PLGA-PHL nanosystem was obtained. The effectiveness of CS-PLGAPHL on the invasion and migration of human oral squamous cell carcinoma cells was discussed, as were their potential mechanisms. Materials and Methods: A CS-PLGA-PHL nanosystem was constructed by emulsion-solvent evaporation. The size distribution, dispersion, and morphology were characterised by the laser particle size analyser and transmission electron microscope. Human oral squamous cell carcinoma drug-resistant cell lines SCC131/R and SCC-15/DDP were cultured in vitro. The two cell types were induced at different concentrations by CS-PLGA-PHL, after which a CCK⁃8 experiment was performed to determine the effect of CS-PLGA-PHL on the proliferation of the two cell lines. The 50% inhibitory concentration (IC50) of CSPLGA- PHL was calculated at different time points. The transwell chamber experiment was performed to identify the effects of CS-PLGA-PHL on the migration and invasion of OSCC cells. The expression levels of MMP-2 and MMP-9 were detected by Western blot and q-PCR. Results: CS-PLGA-PHL is well dispersed. The PDI appeared to be lowest when the mass ratio of chitosan to PLGA equaled 1:15. CS-PLGA-PHL exhibited a marked effect in inhibiting the proliferation of SCC- 131/R and SCC-15/DDP as well as the invasion and migration. CS-PLGA-PHL was able to downregulate the expression of MMP-2 and MMP-9 genes and proteins significantly in drug-resistant cell lines. Conclusion: CS-PLGA-PHL for oral squamous cell carcinoma has been successfully prepared to exert significant inhibition on the proliferation, invasion, and migration of OSCC cells. The mechanism involved was possibly related to the down-regulation of MMP-2 and MMP-9 expression by CS-PLGA-PHL.

Sacubitril/valsartan inhibits the proliferation of vascular smooth muscle cells through notch signaling and ERK1/2 pathway

AimsTo explore the role and mechanism of Notch signaling and ERK1/2 pathway in the inhibitory effect of sacubitril/valsartan on the proliferation of vascular smooth muscle cells (VSMCs).Main methodsHuman aortic vascular smooth muscle cells (HA-VSMCs) were cultured in vitro. The proliferating VSMCs were divided into three groups as control group, Ang II group and Ang II + sacubitril/valsartan group. Cell proliferation and migration were detected by CCK8 and scratch test respectively. The mRNA and protein expression of PCNA, MMP-9, Notch1 and Jagged-1 were detected by qRT-PCR and Western blot respectively. The p-ERK1/2 expression was detected by Western blot.Key findingsCompared with the control group, proliferation and migration of VSMCs and the expression of PCNA, MMP-9, Notch1, Jagged-1 and p-ERK1/2 was increased in Ang II group. Sacubitril/valsartan significantly reduced the proliferation and migration. Additionally, pretreatment with sacubitril/valsartan reduced the PCNA, MMP-9, Notch1, Jagged-1 and p-ERK1/2 expression.

Vocal fold fibroblasts and exposure to vibration in vitro: Does sex matter?

Studies have shown that certain vocal fold pathologies are more common in one sex than the other. This is often explained by differences in the composition of the lamina propria and anatomical differences between female and male vocal folds, resulting in e.g. different fundamental frequencies. Here, we investigated a potential sex-specific voice frequency effect in an in vitro setting using vocal fold fibroblasts from one male and one female donor with and without cigarette smoke extract (CSE) addition. After exposure to either male or female vibration frequency with or without CSE, cells and supernatants were harvested. Gene and protein analysis were performed by means of qPCR, western blot, ELISA and Luminex. We found that exposure of cells to both male and female vibration pattern did not elicit significant changes in the expression of extracellular matrix-, inflammation-, and fibrosis-related genes, compared to control cells. The addition of CSE to vibration downregulated the gene expression of COL1A1 in cells exposed to the female vibration pattern, as well as induced MMP1 and PTGS2 in cells exposed to both female and male vibration pattern. The protein expression of MMP1 and COX2 was found to be significantly upregulated only in cells exposed to CSE and female vibration pattern. To conclude, different vibration patterns alone did not cause different responses of the cells. However, the female vibration pattern in combination with CSE had a tendency to elicit/maintain more pro-inflammatory responses in cells than the male vibration pattern.

Electrical stimulation promoting the angiogenesis in diabetic rat perforator flap through attenuating oxidative stress-mediated inflammation and apoptosis.

Skin flap transplantation is one of the effective methods to treat the diabetes-related foot ulceration, but the intrinsic damage to vessels in diabetes mellitus (DM) leads to the necrosis of skin flaps. Therefore, the discovery of a non-invasive and effective approach for promoting the survival of flaps is of the utmost importance. Electrical stimulation (ES) promotes angiogenesis and increases the proliferation, migration, and elongation of endothelial cells, thus being a potential effective method to improve flap survival. The purpose of this study was to elucidate the mechanism used by ES to effectively restore the impaired function of endothelial cells caused by diabetes. A total of 79 adult male Sprague-Dawley rats were used in this study. Gene and protein expression was assessed by PCR and western blotting, respectively. Immunohistochemistry and hematoxylin-eosin staining were performed to evaluate the morphology and density of the microvessels in the flap. The optimal duration for preconditioning the flap with ES was 7 days. The flap survival area percentage and microvessels density in the DMES group were markedly increased compared to the DM group. VEGF, MMP2, and MMP9 protein expression was significantly upregulated. ROS intensity was significantly decreased and GSH concentration was increased. The expression of IL-1β, MCP‑1, cleaved caspase-3, and Bax were downregulated in the DMES group, while TGF-β expression was upregulated. ES improves the angiogenesis in diabetic ischemic skin flaps by attenuating oxidative stress-mediated inflammation and apoptosis, eventually increasing their viability.

Quercetin Alleviates Lipopolysaccharide-Induced Cardiac Inflammation via Inhibiting Autophagy and Programmed Cell Death

ObjectiveThe aim of this study is to explore the potential modulatory role of quercetin against Endotoxin or lipopolysaccharide (LPS) induced septic cardiac dysfunction. MethodsSpecific pathogen-free chicken embryos (n = 120) were allocated untreated control, phosphate buffer solution (PBS) vehicle, PBS with ethanol vehicle, LPS (500 ng/egg), LPS with quercetin treatment (10, 20, or 40 nmol/egg, respectively), Quercetin groups (10, 20, or 40 nmol/egg). Fifteen-day-old embryonated eggs were inoculated with abovementioned solutions via the allantoic cavity. At embryonic day 19, the hearts of the embryos were collected for histopathological examination, RNA extraction, real-time polymerase chain reaction, immunohistochemical investigations, and Western blotting. ResultsThey demonstrated that the heart presented inflammatory responses after LPS induction. The LPS-induced higher mRNA expressions of inflammation-related factors (TLR4, TNFα, MYD88, NF-κB1, IFNγ, IL-1β, IL-8, IL-6, IL-10, p38, MMP3, and MMP9) were blocked by quercetin with three dosages. Quercetin significantly decreased immunopositivity to TLR4 and MMP9 in the treatment group when compared with the LPS group. Quercetin significantly decreased protein expressions of TLR4, IFNγ, MMP3, and MMP9 when compared with the LPS group. Quercetin treatment prevented LPS-induced increase in the mRNA expression of Claudin 1 and ZO-1, and significantly decreased protein expression of claudin 1 when compared with the LPS group. Quercetin significantly downregulated autophagy-related gene expressions (PPARα, SGLT1, APOA4, AMPKα1, AMPKα2, ATG5, ATG7, Beclin-1, and LC3B) and programmed cell death (Fas, Bcl-2, CASP1, CASP12, CASP3, and RIPK1) after LPS induction. Quercetin significantly decreased immunopositivity to APOA4, AMPKα2, and LC3-II/LC3-I in the treatment group when compared with the LPS group. Quercetin significantly decreased protein expressions of AMPKα1, LC3-I, and LC3-II. Quercetin significantly decreased the protein expression to CASP1 and CASP3 by immunohistochemical investigation or Western blotting in treatment group when compared with LPS group. ConclusionQuercetin alleviates cardiac inflammation induced by LPS through modulating autophagy, programmed cell death, and myocardiocytes permeability.

Potential antiaging activity of secretome gel of human Wharton's jelly mesenchymal stem cells (hWJ-MSCs) in UV-induced mice models.

Skin aging is a degenerative process that can be induced by UV irradiation. UV radiation can produce reactive oxidate stress which causes premature aging. This study aims to examine the antiaging potential of secretome gel (SC) from human Wharton Jelly Mesenchymal Stem Cells (hWJ-MSCs) in a UVB-induced mice model. The secretome was obtained from hWJ-MSCs and made in gel form. Male mice were radiated by UVB for 15 min twice daily for 14 days. The gel was topically applied to the mice's dorsal skin. Two treatments of secretome gel: secretome 1 is applied once and secretome 2 is applied twice daily after UVB radiation. TGF-β1, IL-10, and IL-18 gene expression was determined using RT-PCR. Hematoxylin Eosin staining was used to observe the inflammation and collagen density of skin tissue. An immunohistochemistry assay was used to analyze the protein expression of P53, COL4A1, MMP-2, and MMP-13. The data were statistically analyzed using the ANOVA test followed by the Tukey post hoc test (P<0.05). UVB induction caused loss of collagen, increasing inflammation and high expression of aging mediators. SC increased the gene expression of TGF-β1 and IL-10 and decreased IL-18 gene expression. Histopathological tests showed that SG increased collagen density, lowered inflammation, and repaired cell damage in skin tissue. Immunohistochemistry test showed that SC decreased MMP-2, MMP-13, and P53 expression, in contrast, increased COL4A1. The secretome gel of hWJ-MSCs showed antiaging activities with potential for preventing and curing skin aging.

The ginsenoside Rg2 downregulates MMP-1 expression in keratinocyte (HaCaT)-conditioned medium-treated human fibroblasts (Hs68)

Keratinocytes exposed to UVB induce the production of cytokines, which activate fibroblasts and increase the expression of matrix metalloproteinases (MMPs). The increased expression of MMPs leads to connective tissue damage and wrinkle formation, resulting in skin aging. In this study, we used human dermal fibroblasts cultured in UVB-irradiated keratinocyte-conditioned medium (UV CM) to investigate the potential anti-aging effects of the ginsenoside Rg2 on skin. The inhibitory effect of Rg2 on the MMP-1 gene and protein was determined by real-time PCR and ELISA. We also examined the expression levels of proteins in the mitogen-activated protein kinase (MAPK) signaling pathway using western blotting, to elucidate the underlying mechanism of the inhibitory effect of Rg2. Rg2 inhibited MMP-1 mRNA and protein expression in a concentration-dependent manner. We found that Rg2 inhibited the phosphorylation of extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) but not that of p38. Therefore, our results suggest that Rg2 is a potential material for the prevention and treatment of photoaging.

Protective Effect of Alpha-Linolenic Acid on Human Oral Squamous Cell Carcinoma Metastasis and Apoptotic Cell Death

Oral cancer ranks sixth among Taiwan’s top 10 cancers and most patients with poor prognosis acquire metastases. The essential fatty acid alpha-linolenic acid (ALA) has been found to diminish many cancer properties. However, the anti-cancer activity of ALA in oral cancer has yet to be determined. We examined the mechanisms underlying ALA inhibition of metastasis and induction of apoptotic cell death in oral squamous cell carcinoma (OSCC). Migration and invasion assays confirmed the cancer cells’ EMT capabilities, whereas flow cytometry and Western blotting identified molecular pathways in OSCC. ALA dramatically reduced cell growth in a concentration-dependent manner according to the findings. Low concentrations of ALA (100 or 200 μM) inhibit colony formation, the expression of Twist and EMT-related proteins, the expression of MMP2/-9 proteins, and enzyme activity, as well as cell migration and invasion. Treatment with high concentrations of ALA (200 or 400 μM) greatly increases JNK phosphorylation and c-jun nuclear accumulation and then upregulates the FasL/caspase8/caspase3 and Bid/cytochrome c/caspase9/caspase3 pathways, leading to cell death. Low concentrations of ALA inhibit SAS and GNM cell migration and invasion by suppressing Twist and downregulating EMT-related proteins or by decreasing the protein expression and enzyme activity of MMP-2/-9, whereas high concentrations of ALA promote apoptosis by activating the JNK/FasL/caspase 8/caspase 3-extrinsic pathway and the Bid/cytochrome c/caspase 9 pathway. ALA demonstrates potential as a treatment for OSCC patients.

Inhibiting miR-33b-5p Enhances Chemoresistance in Lung Adenocarcinoma by Targeting YWHAH to Regulate Epithelial-mesenchymal Transition.

Lung adenocarcinoma (LUAD) is the most malignant type of lung cancer, whose clinical treatment is seriously hindered by chemoresistance. Numerous reports have demonstrated that miR-33b-5p plays an essential role in alleviating the chemoresistance of multiple cancers, but there are currently no reports about the effects of miR-33b-5p on the chemoresistance in LUAD. Our study aimed to investigate the impacts of miR-33b-5p on the chemoresistance in LUAD and the underlying mechanism. Bioinformatics analyses were employed to investigate the relation between miR-33b-5p and YWHAH. The MTT assay and flow cytometry were respectively adopted to determine cell viability and apoptosis. A transwell assay was employed to evaluate cellular invasion and migration. qRT-PCR and western blotting were respectively employed to detect the gene expression of miR-33b-5p and the protein expression of YWHAH, MMP2, Snail, and Zeb1. Three bioinformatics analysis approaches predicted that YWHAH was the underlying targeted gene of miR-33b-5p and revealed the associated mechanisms. The concentration of paclitaxel (TAX) and cisplatin (DDP) needed to induce chemoresistance of LUAD cells was determined as 100 μM. Migration and invasion, as well as protein expression of YWHAH, MMP2, MMP8, Snail and Zeb1 were increased, but the apoptosis and levels of miR-33b-5p were reduced in A549 cells with chemoresistance. Knockdown of miR-33b-5p exerted the same effects produced by chemoresistance, but additional knockdown of YWHAH reversed the effects generated by inhibiting miR-33b-5p. Our study confirmed that knockdown of miR-33b-5p aggravated chemoresistance in LUAD via targeting YWHAH to regulate EMT.

Effects of miR-143 on the migration and invasion of osteosarcoma cells by regulating MMP-13 expression

To explore the effect of miR-143 regulating matrix metalloproteinase(MMP)-13 expression on migration and invasion of osteosarcoma cells. The mouse osteosarcoma cell line 143B cells were cultured in 96-well plates, and blank group, negative group, positive group, and intervention group were set up. Then, the blank group did no treatment 50 μg miR-143 mimic was added to positive group, negative group added equal mimic NC (control sequence of miR-143 mimic), the intervention group was added 50 μg miR-143 mimic and 10 μg MMP-13 protein, all groups continued to culture for 3 to 6 hours, and finally the serum was aspirated to treat for half an hour. The protein expressions of miR-143 and MMP-13 in each group were measured by fluorescence quantitative PCR experiment and Western blot experiment, respectively, and the invasion and migration abilities of cells were measured by Transwell and scratch experiments. The expression of MMP-13 protein in the positive group and the intervention group was significantly lower than that in the blank group, and the positive group was lower than the intervention group (P<0.05);The mean numbers of invasive cells in blank group, negative group, positive group and intervention group were (1 000.01±44.77), (959.25±46.32), (245.04±4.33), (634.06±33.78) cells/field, respectively;the scratch healing rate of the positive group and the intervention group was significantly lower than that of the blank group, and the positive group was lower than the intervention group (P<0.05). MMP-13 is a target of miR-143, which can reduce the migration and invasion ability of osteosarcoma cells by inhibiting the expression of MMP-13.

The clock gene Bmal1 controls inflammatory mediators in rheumatoid arthritis fibroblast-like synoviocytes

ObjectTo clarify the involvement of clock genes in the production of inflammatory mediators from RA-FLS, we examined the role of Bmal1, one of the master clock genes. MethodsRA-FLSs were stimulated with IL-1β (0, 20 ng/mL), IL-6 (0, 20 ng/mL), IL-17 (0, 20 ng/mL), TNF-α (0, 20 ng/mL) or IFN-γ (0, 20 ng/mL) to examine the expression of Bmal1, MMP-3, CCL2, IL-6, IL-7 and IL-15 by qPCR and immunofluorescence staining. After silencing Bmal1, RA-FLSs were stimulated with IL-1β (0, 20 ng/mL), TNF-α (0, 20 ng/mL) or IFN-γ (0, 20 ng/mL) to examine the expressions of inflammatory mediators; MMP-3, CCL2, IL-6 and IL-15 by qPCR, ELISA and immunofluorescence staining. ResultsBmal1 expressions were increased by IL-1β, TNF-α and IFN-γ stimulations. Under stimulations with TNF-α, IL-1β, and IFN-γ, mRNA and protein expressions of MMP-3, CCL2 and IL-6 were suppressed by siBmal1. ConclusionResults indicate that Bmal1 contributes the production of MMP-3, CCL2, and IL-6 from RA-FLS, implying Bmal1 is involved in the pathogenesis of RA by regulating the inflammation.

Effects of SU5416 on angiogenesis and the ERK-VEGF/MMP-9 pathway in rat endometriosis.

SU5416 is a small molecule vascular endothelial growth factor (VEGF) receptor signal transduction inhibitor, which can block the VEGF re-ceptor autophosphorylation and inhibit receptor tyrosine kinase signal trans-duction, thereby reducing VEGF activity. However, there are few reports about the correlation of SU5416 to the occurrence and angiogenesis in endometrio-sis. In this study, we observed the effects of VEGF receptor inhibitor SU5416 on angiogenesis in endometriosis in rats. Thirty femalespecific-pathogen-free Sprague-Dawley rats were randomly divided into sham operation group (SOG), model group (MG), and SU5416 group (n=10 for each group). In the SOG, only the uterus was cut and sutured, and endometriosis models were established in the MG and SU5416 group by autologous transplantation. The SU5416 group was injected with 15 mg/kg SU5416 intraperitoneally, and the SOG and MG were intraperitoneally injected with an equal volume of normal saline for 6 weeks. The volume of ectopic lesions was lower in the SU5416 group at 42 d postoperatively thanin the MG (p&lt;0.05). The proportion of CD31-positive cells in the endometrial tissue of the SU5416 group was lower than that of the MG (p&lt;0.05); angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), laminin-5γ2 (LN-5γ2) and phosphorylation of ERK (P-ERK), VEGF, matrix metalloproteinase (MMP)-2, and MMP-9 protein expressions were lower in the SU5416 groupthan in the MG (p&lt;0.05).VEGFreceptor inhibitor SU5416 can inhibit endometrio-sis angiogenesis and reduce inflammatory response in rats, and its mechanism of action may be related to the down-regulation of the ERK-VEGF/MMP-9 path-way expression.

PF-04449913 Inhibits Proliferation and Metastasis of Colorectal Cancer Cells by Down-regulating MMP9 Expression through the ERK/p65 Pathway.

Colorectal cancer remains a life-threatening malignancy with increasing morbidity and mortality worldwide. Therefore, new and effective anti-colorectal cancer therapeutics are urgently needed. In this study, we have studied the anti-tumor properties and potential mechanisms of PF-04449913. Colorectal cancer cell viability was reduced by PF-04449913 in a dose-dependent manner. The migration and invasion ability of malignant colon cells were attenuated by the drug, as demonstrated by the Transwell test. Moreover, PF-04449913 repressed the phosphorylation levels of ERK and other proteins, and the expression levels of MMP9. The anti-tumor effects of the drug in vivo were demonstrated in BALB/c-nude mice models, and PF-04449913 inhibited the malignant phenotype of colorectal cancer cells, including reduction of tumor size and promotion of apoptosis. At the molecular level, PF-04449913 induced a significant decrease in ERK and p65 protein phosphorylation levels and inhibited MMP9 protein expression. Both in vivo and in vitro results showed PF-04449913 to demonstrate antitumor effects, which have been proposed to be mediated through blockade of the ERK/p65 signaling pathway, and subsequent repression of MMP9 expression. Our study provides a new perspective on the potential clinical application of PF-04449913 in the treatment of colorectal cancer.

MTOR Inhibitor Rapalink-1 Prevents Ethanol-Induced Senescence in Endothelial Cells.

The cardiovascular risk factors, including smoking, ethanol, and oxidative stress, can induce cellular senescence. The senescent cells increase the expression and release of pro-inflammatory molecules and matrix metalloproteinase (MMPs). These pro-inflammatory molecules and MMPs promote the infiltration and accumulation of inflammatory cells in the vascular tissue, exacerbating vascular tissue inflammation. MMPs damage vascular tissue by degenerating the extracellular matrix. Consequently, these cellular and molecular events promote the initiation and progression of cardiovascular diseases. We used Rapalink-1, an mTOR inhibitor, to block ethanol-induced senescence. Rapalink-1 inhibited oxidative-stress-induced DNA damage and senescence in endothelial cells exposed to ethanol. It attenuated the relative protein expression of senescence marker P21 and improved the relative protein expression of DNA repair protein KU70 and aging marker Lamin B1. It inhibited the activation of NF-κB, MAPKs (P38 and ERK), and mTOR pathway proteins (mTOR, 4EBP-1, and S6). Moreover, Rapalink-1 suppressed ethanol-induced mRNA expression of ICAM-1, E-selectin, MCP-1, IL-8, MMP-2, and TIMP-2. Rapalink-1 also reduced the relative protein expression of MMP-2. In summary, Rapalink-1 prevented senescence, inhibited pro-inflammatory pathway activation, and ameliorated pro-inflammatory molecule expression and MMP-2.

Melatonin Exerts Prominent, Differential Epidermal and Dermal Anti-Aging Properties in Aged Human Eyelid Skin Ex Vivo.

Human skin aging is associated with functional deterioration on multiple levels of physiology, necessitating the development of effective skin senotherapeutics. The well-tolerated neurohormone melatonin unfolds anti-aging properties in vitro and in vivo, but it remains unclear whether these effects translate to aged human skin ex vivo. We tested this in organ-cultured, full-thickness human eyelid skin (5-6 donors; 49-77 years) by adding melatonin to the culture medium, followed by the assessment of core aging biomarkers via quantitative immunohistochemistry. Over 6 days, 200 µM melatonin significantly downregulated the intraepidermal activity of the aging-promoting mTORC1 pathway (as visualized by reduced S6 phosphorylation) and MMP-1 protein expression in the epidermis compared to vehicle-treated control skin. Conversely, the transmembrane collagen 17A1, a key stem cell niche matrix molecule that declines with aging, and mitochondrial markers (e.g., TFAM, MTCO-1, and VDAC/porin) were significantly upregulated. Interestingly, 100 µM melatonin also significantly increased the epidermal expression of VEGF-A protein, which is required and sufficient for inducing human skin rejuvenation. In aged human dermis, melatonin significantly increased fibrillin-1 protein expression and improved fibrillin structural organization, indicating an improved collagen and elastic fiber network. In contrast, other key aging biomarkers (SIRT-1, lamin-B1, p16INK4, collagen I) remained unchanged. This ex vivo study provides proof of principle that melatonin indeed exerts long-suspected but never conclusively demonstrated and surprisingly differential anti-aging effects in aged human epidermis and dermis.

Phenotype and function of smooth muscle cells derived from the human normal great saphenous vein in response to hypoxia.

The contribution of hypoxia to the pathophysiology of vascular smooth muscle cells (VSMCs) has not yet been fully elucidated. This study evaluated the effect of hypoxia on the phenotype and function of SMCs derived from the human normal great saphenous veins (NGSVs). Fifteen NGSV tissue samples were collected. SMCs were isolated and cultured. Proliferation, migration, adhesion, senescence, and the structure of cytoskeletal filaments in SMCs were observed. mRNA and protein expression of Bax, Bcl-2, caspase-3, matrix metalloproteinases (MMP)-2, MMP-9, tissue inhibitor of metalloproteinases (TIMP)-1, and TIMP-2 was detected by fluorescent quantitative polymerase chain reaction and immunoblotting in the cobalt chloride (CoCl2) and the control groups. A decrease in the number of cytoskeletal filaments was observed. mRNA and protein expression of Bas and caspase-3 was significantly decreased, while the quantity of proliferation, migration, adhesion, senescence, and mRNA and protein expression of Bcl-2, MMP-2, MMP-9, TIMP-1, and TIMP-2 in SMCs in the CoCl2 group were significantly increased compared with the control group. Under hypoxic conditions, the phenotype and function of SMCs derived from the human NGSVs were dysregulated, suggesting that VSMCs switch from the contractile phenotype to the secretory or synthetic phenotype, and more dedifferentiate, resulting in extracellular matrix deposition and apoptotic decrease through the intrinsic pathway.

Corosolic acid inhibits metastatic response of human renal cell carcinoma cells by modulating ERK/MMP2 signaling.

Corosolic acid (CA), a plant-derived pentacyclic triterpenoid, has potent anti-inflammatory, anti-metabolic, and anti-neoplastic actions against a variety of human cancers. However, the specific mechanism by which CA inhibits the progression of renal cell carcinoma (RCC) is yet unclear. We found that CA (≤8 μM) had no influence on either the growth or viability of RCC cell lines (786-O, ACHN, and Caki-1) or normal HK2 cells. However, in a dose-dependent manner, CA prevented the invasion and migration of RCC cells. Human protease array analysis showed that CA reduced MMP2 expression. At increasing concentrations of CA, the expression of MMP2 was dose-dependently reduced, as shown by western blot and RT-PCR analyses as well as immunofluorescence staining. CA also stimulated ERK1/2 phosphorylation in 786-O and Caki-1 cells. Transfection of CA-treated RCC cells with siRNA-ERK restored MMP2 protein expression and the motility and invasion capabilities of RCC cells. Molecular docking study results showed that CA and MMP2 interact strongly. These findings elucidate the mechanism by which CA prevents RCC cells from migrating and invading, and these findings indicate that CA may be a potential anti-metastatic therapy for RCC.

IgE Immune Complexes Mitigate Eosinophilic Immune Responses through NLRC4 Inflammasome.

Immune complexes (ICs) skew immune responses toward either a pro- or anti-inflammatory direction based on the type of stimulation. Immunoglobulin E (IgE) is associated with Th2 immune responses and known to activate innate immune cells. However, roles of antigen (Ag)-specific-IgE ICs in regulating human eosinophil responses remain elusive; therefore, this study builts upon the mechanism of which ovalbumin (Ova)-IgE ICs affects eosinophilic responses utilizing human EoL-1 cell line as a model. Eosinophils are granulocytes functioning through pattern recognition receptors (PRRs) and destructive granule contents in allergic inflammation and parasitic infections. One of the PRRs that eosinophils express is NLRC4, a member of the CARD domain containing nucleotide-binding oligomerization (NOD)-like receptor (NLR) family. Upon recognition of its specific ligand flagellin, NLRC4 inflammasome is formed and leads to the release of interleukin-1β (IL-1β). We exhibited that Ova-IgE ICs induced the NLRC4-inflammasome components, including NLRC4, caspase-1, intracellular IL-1β, and secretion of IL-1β, as well as the granule contents MMP9, TIMP1, and TIMP2 proteins via TLR2 signaling; these responses were suppressed, when NLRC4 inflammasome got actived in the presence of ICs. Furthermore, Ova-IgE ICs induced mRNA expressions of MMP9, TIMP2, and ECP and protein expressions of MMP9 and TIMP2 in EoL-1 through FcɛRII. Interestingly, TLR2 ligand and Ova-IgE ICs costimulation elevated the number of CD63+ cells, a degranulation marker, as compared to the native IgE. Collectively, our findings provide a mechanism for the impacts of Ova-IgE ICs on eosinophilic responses via NLRC4-inflammasome and may help understand eosinophil-associated diseases, including chronic eosinophilic pneumonia, eosinophilic esophagitis, eosinophilic granulomatosis, parasitic infections, allergy, and asthma.