Tenascin-C (TNC) is an extracellular matrix glycoprotein, which is usually highly expressed in embryonic tissues and tumor tissues, but is not expressed or just lowly expressed in mature tissues. TNC is involved in various complex signaling pathways during tumor metastasis, especially through modulating FAK, RhoA, Wnt and Notch pathways by interacting with syndecan-4, integrinα5β1, matrix metalloproteinases (MMPs) and vascular endothelial growth factor (VEGF). As a result, TNC affects epithelial mesenchymal transition, tumor cell adhesion, proliferation and angiogenesis, which eventually enhances the invasion and metastasis ability of many tumors. Further studies have demonstrated that TNC could be used as prognosis or metastasis marker of patients with malignant tumor.
Objective To investigate the effect of Wnt/β-catenin signal pathway on the apoptosis in steroid-induced avascular necrosis of femoral head (SANFH) in rats. Methods Seventy-two male Sprague Dawley rats (weighing, 200-230 g) were randomly divided into the control group (group A, n=24), the model group (group B, n=24), and the intervening group (group C, n=24). The rats in groups B and C were injected with lipopolysaccharide and methylprednisolone (MPS) to establish the SANFH model. The rats in group C were injected intramuscularly with human recombinant secreted frizzled related protein 1 (SFRP1) [1 μg/(kg·d)] at the first time of MPS administration for 30 days. The rats in group A received saline injection at the same injection time of group B. The general condition of rats in groups B and C was observed during modeling and after modeling. At 2, 4, and 8 weeks after last injection of MPS, 8 rats were sacrificed to harvest the femoral head. Histological staining was performed to evaluate osteonecrosis. Apoptosis was detected via TUNEL staining. The expressions of Wnt/β-cate nin pathway signaling molecules (activated β-catenin and c-Myc) were detected by immunohistochemistry and Western blot. Results Six rats were added in groups B and C because of 6 deaths. The other rats survived to the end of experiment. Normal bone structure was observed in group A; osteonecrosis of bone structure disturbance and disruption of the trabecula were found with time in groups B and C. Group C had the highest empty lacuna rate and apoptosis rate, followed by groups B and A, showing significant difference between groups (P < 0.05). The expression levels of activated β-catenin and c-Myc were significantly lower in group C than groups A and B (P < 0.05), and in group B than group A (P < 0.05). Conclusion Wnt/β-catenin signal pathway is involved in the pathogenesis in early SANFH model and its possible mechanism is to affect the cell cycle and cell apoptosis by the regulation of c-Myc expression.
Objective To investigate the molecular signal mechanism of transform growth factor (TGF)-β induced arterial endothelial-mesenchymal transition. Methods Rat arterial endothelial cells were primarily cultured by ex-transplant method. The endothelial cells were incubated by combinant TGF-β (10 ng/mL) for 48 hours and then were detected by immunofluorescence staining and western blotting to observe the cell surface marker expression profile and Akt/mTOR signal activation. On the other hand, the endothelial cells were preincubated by Ly294002 (20 μmol/L) and rapamycin (10 nmol/L) to inhibit the Akt/mTOR signal, and then the cells were further treated with TGF-β (10 ng/mL) for 48 hours to observe the cell surface marker expression profile without Akt/mTOR signal activation. Results Rat artery endothelial cells by TGF-β after incubation, the expressions of smooth muscle cell markers α-smooth muscle actin (α-SMA) and smooth muscle-22α (SM-22α) were up-regulated, and the endothelial cell markers CD31 and vW factor were significantly down-regulated, at the same time, the expressions of phosphorylated Akt and mTOR were also up-regulated. However, after preincubation of Ly294002 (20 μmol/L) and rapamycin (10 nmol/L) to inhibit the phosphorylation of Akt and mTOR signal, above TGF-β-induced expressions of α-SMA and SM-22α in arterial endothelial cells were significantly suppressed and the expressions of CD31 and vWF were preserved. Conclusion TGF-β-induced arterial endothelial-mesenchymal transition is dependent on activation of Akt/mTOR signal, suggesting that Akt/mTOR-dependent arterial endothelial-mesenchymal transition would be one of the mechanisms for intima hyperplasia in transplant arteriosclerosis.
Objective To explore the expression of yes-associated protein 1 (YAP1), as a key protein of Hippo signal pathway, in rats with brain injury. Methods A total of 18 Sprague Dawley rats were randomly divided into three groups: normal group, sham operation group and brain injury group. The expression of YAP1 in rats with brain injury was detected by immunochemistry, quantitative polymerase chainreaction and Western blotting. Result Seventy-two hours after the brain injury, the expression level of YAP1 in protein and gene increased significantly in brain injury group, compared with those in the normal and sham operation group (P<0.05). Conclusion The expression of YAP1 increases in rats with brain injury, which maybe a new target for therapy.
Objective To investigate the effect and mechanism of epigallocatechin-3-gallate (EGCG) on restenosis of the vein graft. Methods Totally 90 Sprague-Dawley rats were randomly divided a the control group, a vein graft group and an EGCG+vein graft group. At week 1, 2 and 4, the intimal and tunica thickness of the venous graft wall was evaluated by hematoxylin-eosin staining, and the expression of Ki-67 was assessed by immunohistochemistry analysis, and then the expression of hairy and enhancer of split-1 (HES1) was measured by Western blot assay. Results At week 2, the intimal thickness (46.76±4.89 μmvs. 8.93±0.82 μm, 46.76±4.89 μmvs. 34.24±3.57 μm), tunica thickness (47.28±4.37vs. 16.33±1.52 μm, 47.28±4.37vs. 36.27±3.29 μm), positive cell rate of Ki-67 (21.59%±2.29%vs. 1.12%±0.22%, 21.59%±2.29%vs. 15.38%±1.30%), expression of HES1 respectively increased in the experimental group than those in the control group and the EGCG+vein graft group (P<0.05, respectively). At week 4, the intimal thickness (66.38±6.23 μmvs. 8.29±0.79 μm, 66.38±6.23 μmvs. 48.39±4.23 μm), tunica thickness (63.27±6.18 μmvs. 15.29±1.49 μm, 63.27±6.18 μmvs. 44.63±4.49 μm), positive cell rate of Ki-67 (33.19%±3.03%vs. 1.09%±0.19%, 33.19%±3.03%vs. 24.37%±2.73%), expression of HES1 increased in the experimental group than those in the control group and EGCG+vein graft group (P<0.05, respectively). Conclusion EGCG may inhibite restenosis of vein graft by inhibiting Notch signal pathway.
ObjectiveTo study immunodepression effect of bone marrow-derived mesenchymal stem cell (BMSC) on acute asthmatic airway inflammation by galectin-1 (gal-1) in vivo.MethodsEighty-five female BALB/c mice were equally randomized into normal control group, asthmatic group, BMSC treatment group, gal-1 treatment group and BMSC and gal-1 inhibitor group. Ovalbumin (OVA) was used to establish acute asthmatic model. Total cell number and differential cell analysis in each group in bronchoalveolar lavage fluid (BALF) were determined. Furthermore, hematoxylin-eosin and periodic-acid Schiff staining was used to compare airway inflammation among five groups. Measurement of cytokines, including interleukin (IL) -4, IL-5 and gal-1 in BALF and OVA specific IgE (OVA-IgE) in serum were evaluated by enzyme linked immunosorbent assay. Moreover, dendritic cell (DC) in lung tissue was sorted by immunomagnetic beads and its MAPK signal pathway was analyzed by western blotting among five groups.ResultsAccumulation of inflammation cells, particularly eosinophils around airway and in BALF was evident in asthmatic mouse model, meanwhile hyperplasia of Goblet cell was also obvious in asthmatic group. BMSC engraftment or gal-1 infusion significantly reduced airway inflammation and hyperplasia of Goblet cell and the number of inflammation cells in BALF, especially eosinophils attenuated dramatically. However, there was no effect on airway inflammation and hyperplasia of Goblet Cell by simultaneous infusion BMSC engraftment and gal-1 inhibitor. Compared to normal control group, the level of IL-4, IL-5 in BALF and OVA-IgE in serum was increased remarkably in asthmatic group, but the level of gal-1 reduced obviously. Moreover, infusion of BMSC or gal-1 could mitigate the level of IL-4, IL-5 in BALF and OVA-IgE in serum and increase the level of gal-1 in asthmatic mouse. However, infusion with both BMSC and gal-1 inhibitor exerted no effect on cytokine and OVA-IgE in asthmatic mouse. DC was sorted by immunomagnetic beads and western blotting was used to detect the expression of MAPK signal pathway among five groups. The expression of ERK phosphorylation in asthmatic group was much lower than that in normal control group. On the contrary, the expression of p38 phosphorylation was much higher than that in normal control group. BMSC engraftment or gal-1 infusion significantly activated the ERK pathway and inhibited the p38 MARP pathway on asthmatic mouse DC. Nevertheless, the expression of ERK phosphorylation and p38 phosphorylation for group with BMSC and gal-1 inhibitor infusion was between the level of asthmatic group and normal control group.ConclusionsBMSC infusion alleviates airway inflammation in asthmatic mouse, especially weakens eosinophils infiltration, and the underlying mechanism might be protective effect of gal-1 secreted by BMSC which plays a role in lung tissue DC and regulates the DC expression of MAPK signal pathway.
ObjectiveTo summarize the anti-inflammatory effects of irisin in inflammatory diseases.MethodThe relevant literatures at home and abroad in recent years were systematically searched and read to review the anti-inflammatory effects of irisin in the inflammatory diseases.ResultsThe irisin was widely distributed in the body and played a physiological role in inducing the browning of white adipocytes, improving energy metabolism and glucose utilization. A grow body of evidences demonstrated that the irisin exerted the anti-inflammatory effects by inhibiting increased pro-inflammatory cytokines and tumor necrosis factor-α, antagonizing apoptosis and activation of nuclear factor-κB, and improving tissue damage in many inflammatory diseases, such as acute lung injury, inflammatory bowel disease, septic cardiomyopathy, acute pancreatitis, nonalcoholic fatty liver disease, and malignant tumors.ConclusionsIrisin plays an important anti-inflammatory role in pathogenesis of inflammatory diseases. Irisin is considered as a promising candidate biomarker for diagnosis and prognosis of inflammatory diseases, and a novel target for treatment of inflammatory diseases.
ObjectiveTo summarize the mechanism of hydrogen sulfide (H2S) in regulating autophagy and ameliorating multi-organ dysfunction in the treatment of sepsis.MethodThe relevant literatures at home and abroad in recent years were systematically searched and read to review the mechanism of H2S in regulating autophagy and ameliorating multi-organ dysfunction during sepsis.ResultsAs a new medical gas signal molecule, H2S could regulate autophagy by regulating multiple signal pathways such as Nrf2, NF-κB, MAPK, AMPK, etc., then ameliorated multi-organ dysfunction in sepsis.ConclusionH2S inhibits inflammation, oxidative stress, and apoptosis by regulating autophagy, thus ameliorating multi-organ dysfunction in sepsis, which is expected to become an effective therapeutic target for sepsis.
ObjectiveTo investigate the effects of hypoxia inducible factor 1α (HIF-1α) overexpression on the differentiation of stem cells derived from human exfoliated deciduous teeth (SHED) into vascular endothelial cells.MethodsSHED was isolated from the retained primary teeth donated by healthy children by using collagenase digestion method. The third generation cells were identified by flow cytometry and alizarin red and alkaline phosphatase (ALP) staining after osteogenic differentiation culture. The SHED were divided into blank control group (SHED without any treatment), empty group (SHED infected with empty lentivirus), HIF-1α overexpression group (SHED infected with HIF-1α overexpression lentivirus), Wnt inhibitor group (SHED interfered by IWR-1), and combination group (HIF-1α overexpressed SHED interfered by IWR-1). Real-time fluorescence quantitative PCR (qRT-PCR) and Western blot were used to analyze the expressions of HIF-1α mRNA and protein in the SHED of blank control group, empty group, and HIF-1α overexpression group. Then the SHED in 5 groups were induced differentiation into vascular endothelial cells for 14 days. The expressions of cell surface marker molecule [von Willebrand factor (vWF) and CD31] were detected by flow cytometry. The mRNA expressions of vascular cell adhesion protein 1 (VCAM-1), KDR (Kinase-inserted domain containing receptor), and VE-cadherin (VE) were analyzed by qRT-PCR. The protein expressions of phosphate-glycogen synthasc kinase 3β (p-GSK3β) and β-catenin were analyzed by Western blot. The tube forming ability of induced cells was detected by Matrigel tube forming experiment. The ability of endothelial cells to phagocytic lipid after differentiation was detected by DiI-labeled acetylated low density lipoprotein (DiI-Ac-LDL) phagocytosis.ResultsAfter identification, the cells were SHED. After lentivirus transfection, compared with the blank control group and the empty group, the expressions of HIF-1α mRNA and protein in the HIF-1α overexpression group increased significantly (P<0.05). Compared with the blank control group and the empty group, the expressions of VCAM-1, KDR, and VE mRNA, the percentages of vWF positive cells and CD31 positive cells, and the relative expression of β-catenin protein were significantly higher (P<0.05), the relative expression of p-GSK3β protein was significantly lower (P<0.05), the number of tubules formed and the ability to phagocytic lipids significantly increased (P<0.05) in the HIF-1α overexpression group; while the indicators in the Wnt inhibitor group were opposite to those in the HIF-1α overexpression group (P<0.05). Compared with the HIF-1α overexpression group, the expressions of VCAM-1, KDR, and VE mRNA, the percentages of vWF positive cells and CD31 positive cells, and the relative expression of β-catenin protein were significantly lower (P<0.05), the relative expression of p-GSK3β protein was significantly higher, and the number of tubules formed and the ability of phagocytosis of lipids significantly reduced, showing significant differences between groups (P<0.05).ConclusionOverexpression of HIF-1α can promote SHED to differentiate into vascular endothelial cells by activating Wnt/β-catenin signaling pathway.
ObjectiveTo summarize the mechanism of long non-coding RNA (lncRNA) in signal pathways related to osteogenic differentiation. Methods Relevant domestic and foreign researches in recent years were consulted. The characteristics and biological functions of lncRNA were introduced, and the specific mechanism of lncRNA regulating related signal pathways in osteogenic differentiation was elaborated. Results The exertion and maintenance of normal function of bone requires the closed coordination of transcription networks and signal pathways. However, most of these signal pathways or networks are dysregulated under pathological conditions that affect bone homeostasis. lncRNA can regulate the differentiation of various bone cells by activating or inhibiting signal pathways to achieve the balance of bone homeostasis, thereby reversing the pathological state of bones and achieving the purpose of treating bone metabolic diseases. Conclusion At present, the research on the mechanism of lncRNA regulating various osteogenic differentiation pathways is still in the early stage. Its in-depth regulator mechanism, especially the cross-talk of complex signal pathways needs to be further studied. And how to apply these molecular targets to clinical treatment is also a big challenge.