ObjectiveTo observe the feasibility of acellular cartilage extracellular matrix (ACECM) oriented scaffold combined with chondrocytes to construct tissue engineered cartilage.MethodsChondrocytes from the healthy articular cartilage tissue of pig were isolated, cultured, and passaged. The 3rd passage chondrocytes were labeled by PKH26. After MTT demonstrated that PKH26 had no influence on the biological activity of chondrocytes, labeled and unlabeled chondrocytes were seeded on ACECM oriented scaffold and cultivated. The adhesion, growth, and distribution were evaluated by gross observation, inverted microscope, and fluorescence microscope. Scanning electron microscope was used to observe the cellular morphology after cultivation for 3 days. Type Ⅱ collagen immunofluorescent staining was used to check the secretion of extracellular matrix. In addition, the complex of labeled chondrocytes and ACECM oriented scaffold (cell-scaffold complex) was transplanted into the subcutaneous tissue of nude mouse. After transplantation, general physical conditions of nude mouse were observed, and the growth of cell-scaffold complex was observed by molecular fluorescent living imaging system. After 4 weeks, the neotissue was harvested to analyze the properties of articular cartilage tissue by gross morphology and histological staining (Safranin O staining, toluidine blue staining, and typeⅡcollagen immunohistochemical staining).ResultsAfter chondrocytes that were mainly polygon and cobblestone like shape were seeded and cultured on ACECM oriented scaffold for 7 days, the neotissue was translucency and tenacious and cells grew along the oriented scaffold well by inverted microscope and fluorescence microscope. In the subcutaneous microenvironment, the cell-scaffold complex was cartilage-like tissue and abundant cartilage extracellular matrix (typeⅡcollagen) was observed by histological staining and typeⅡcollagen immunohistochemical staining.ConclusionACECM oriented scaffold is benefit to the cell adhesion, proliferation, and oriented growth and successfully constructes the tissue engineered cartilage in nude mouse model, which demonstrates that the ACECM oriented scaffold is promise to be applied in cartilage tissue engineering.
ObjectiveTo study the feasibility of human adipose-derived stem cells (hADSCs) combined with small intestinal submucosa powder (SISP)/chitosan chloride (CSCl)-β-glycerol phosphate disodium (GP)-hydroxyethyl cellulose (HEC) for adipose tissue engineering. MethodshADSCs were isolated from human breast fat with collagenase type I digestion, and the third passage hADSCs were mixed with SISP/CSCl-GP-HEC at a density of 1×106 cells/mL. Twenty-four healthy female nude mice of 5 weeks old were randomly divided into experimental group (n=12) and control group (n=12), and the mice were subcutaneously injected with 1 mL hADSCs+SISP/CSCl-GP-HEC or SISP/CSCl-GP-HEC respectively at the neck. The degradation rate was evaluated by implant volume measurement at 0, 1, 2, 4, and 8 weeks. Three mice were euthanized at 1, 2, 4, and 8 weeks respectively for general, histological, and immunohistochemical observations. The ability of adipogenesis (Oil O staining), angiopoiesis (CD31), and localized the hADSCs (immunostaining for human Vimentin) were identified. ResultsThe volume of implants of both groups decreased with time, but it was greater in experimental group than the control group, showing significant difference at 8 weeks (t=3.348, P=0.029). The general observation showed that the border of implants was clear with no adhesion at each time point;fat-liked new tissues were observed with capillaries on the surface at 8 weeks in 2 groups. The histological examinations showed that the structure of implants got compact gradually after injection, and SISP gradually degraded with slower degradation speed in experimental group;adipose tissue began to form, and some mature adipose tissue was observed at 8 weeks in the experimental group. The Oil O staining positive area of experimental group was greater than that of the control group at each time point, showing significant difference at 8 weeks (t=3.411, P=0.027). Immunohistochemical staining for Vemintin showed that hADSCs could survive at each time point in the experimental group;angiogenesis was most remarkable at 2 weeks, showing no significant differences in CD31 possitive area between 2 groups (P>0.05), but angiogenesis was more homogeneous in experimental group. ConclusionSISP/CSCl-GP-HEC can use as scaffolds for hADSCs to reconstruct tissue engineered adipose.
ObjectiveTo understand the research progress of the matrix metalloproteinases (MMPs) family in regulating the development of hepatocellular carcinoma (HCC) and its mechanism, in order to provide a reference for the basic research and clinical diagnosis and treatment of HCC. MethodThe relevant literature on the regulation of HCC occurrence, development, and mechanisms by MMPs both domestically and internationally in recent years was reviewed. ResultsThe extracellular matrix (ECM) microenvironment of HCC cells determined the invasiveness and degree of metastasis of tumor cells. The degradation and remodeling of ECM during epithelial mesenchymal transition (EMT) were the main factors contributing to the invasion and metastasis of HCC. The abnormal expression of most members of the MMPs family could lead to ECM breakdown, cell invasion and attachment, and markedly accelerate the process of EMT, thereby promoting the invasion and metastasis of HCC cells. At present, there were many MMPs related to the development of HCC, including MMP-1, 2, 3, 7, 9, 12, 13, 14. The relevant research on the relation between MMP-8, 10, 11, 15, 16, 20, 21, 26 or 28 and the development of HCC was relatively limited, while the exact research on the relationship between the MMP-17, 19, 23, 24, 25 or 27 and HCC development had not been retrievaled. ConclusionsThe MMPs family members (especially MMP-2, 3, 7, 9, 10, 12) play a crucial role in the progression of HCC, including proliferation, invasion, and metastasis. Further exploration of the potential intrinsic relation between all members of the MMPs family members and the development of HCC is crucial for predicting HCC metastasis potentiality and prognosis, as well as developing new or improved targeted anti-cancer therapies for HCC.
ObjectiveTo investigate the regulatory effect of resveratrol (RES) on the extracellular matrix (ECM) expression of nucleus pulposus cells (NPC), and its relative molecular mechanism.MethodsTen patients receiving discectomy were collected, of which 5 patients were young with spinal burst fracture, classified as control group; the rest 5 patients were senile with lumbar disc herniation, classified as degenerative group. The nucleus pulposus tissue of 2 groups were collected, the in situexpression of β-catenin was detected by immunohistochemistry, and the protein expressions of collagen type Ⅱ and Aggrecan were detected by Western blot. The NPC were isolated and cultured from degenerative nucleus pulposus tissues. RES treated the third-passage NPC with (group B) or without IL-1β (group C), to further determine the protein expressions of collagen type Ⅱ and Aggrecan by Western blot, the unstimulated cells were set up as blank control group (group A). Moreover, NPC treated with small interfering RNA (siRNA) targeted silent SIRT1 or β-catenin were used to determine the protein and gene expressions of β-catenin and SIRT1 by Western blot and real-time fluorescence quantitative PCR. In addition, the third-passage NPC treated with complete medium (group 1), IL-1β (group 2), RES+IL-1β (group 3), and SIRT1-siRNA+RES+IL-1β (group 4) for 24 hours were used to detect the nuclear translocation of β-catenin by cell immunofluorescence staining. Finally, the third-passage NPC treated with complete medium (group Ⅰ), IL-1β (group Ⅱ), IL-1β+β-catenin-siRNA (group Ⅲ), IL-1β+RES (group Ⅳ), and IL-1β+RES+SIRT1-siRNA (group Ⅴ) for 24 hours were used to detect the protein expressions of collagen type Ⅱ and Aggrecan by Western blot.ResultsImmunohistochemical staining and Western blot detection showed that when compared with control group, the cell proportion of expression of β-catenin were significantly increased in degenerative group (t=4.616, P=0.010); the protein expression of β-catenin was also significantly increased and the protein expressions of collagen type Ⅱ and Aggrecan were significantly decreased (P<0.05). In cytology experiments, the protein expression of β-catenin in group B was significantly higher than that in groups A and C, and the protein expressions of collagen type Ⅱ and Aggrecan in group B were significantly lower than those in groups A and C (P<0.05). After transfection of siRNA, the protein expressions of SIRT1 and β-catenin significantly decreased (P<0.05). The results of cell immunofluorescence staining further confirmed that when compared with group 3, after the SIRT1 was silenced by siRNA in group 4, the attenuated nuclear translocation of β-catenin by RES treatment was aggravated. Western blot results showed that the protein expressions of collagen type Ⅱ and Aggrecan in group Ⅱ were significantly lower than those in group Ⅰ(P<0.05); after transfection of β-catenin-siRNA in group Ⅲ, the degradation of ECM by IL-1β was obviously inhibited, the protein expressions of collagen type Ⅱ and Aggrecan were significantly increased when compared with group Ⅱ (P<0.05); after transfection of SIRT1-siRNA in group Ⅴ, the protective effect of RES on the degradation of ECM was inhibited, the protein expressions of collagen type Ⅱ and Aggrecan were significantly decreased when compared with group Ⅳ (P<0.05).ConclusionRES regulates the ECM expression of NPC via Wnt/β-catenin signaling pathway, which provide a new idea for intervertebral disc degeneration disease treatment.
ObjectiveThe tissue engineered osteochondral integration of multi-layered scaffold was prepared and the related mechanical properties and biological properties were evaluated to provide a new technique and method for the repair and regeneration of osteochondral defect.MethodsAccording to blend of different components and proportion of acellular cartilage extracellular matrix of pig, nano-hydroxyapatite, and alginate, the osteochondral integration of multi-layered scaffold was prepared by using freeze-drying and physical and chemical cross-linking technology. The cartilage layer was consisted of acellular cartilage extracellular matrix; the middle layer was consisted of acellular cartilage extracellular matrix and alginate; and the bone layer was consisted of nano-hydroxyapatite, alginate, and acellular cartilage extracellular matrix. The biological and mechanics characteristic of the osteochondral integration of multi-layered scaffold were evaluated by morphology observation, scanning electron microscope observation, Micro-CT observation, porosity and pore size determination, water absorption capacity determination, mechanical testing (compression modulus and layer adhesive strength), biocompatibility testing [L929 cell proliferation on scaffold assessed by MTT assay, and growth of green fluorescent protein (GFP)-labeled Sprague Dawley rats’ bone marrow mesenchumal stem cells (BMSCs) on scaffolds].ResultsGross observation and Micro-CT observation showed that the scaffolds were closely integrated with each other without obvious discontinuities and separation. Scanning electron microscope showed that the structure of the bone layer was relatively dense, while the structure of the middle layer and the cartilage layer was relatively loose. The pore structures in the layers were connected to each other and all had the multi-dimensional characteristics. The porosity of cartilage layer, middle layer, and bone layer of the scaffolds were 93.55%±2.90%, 93.55%±4.10%, and 50.28%±3.20%, respectively; the porosity of the bone layer was significantly lower than that of cartilage layer and middle layer (P<0.05), but no significant difference was found between cartilage layer and middle layer (P>0.05). The pore size of the three layers were (239.66±35.28), (153.24±19.78), and (82.72±16.94) μm, respectively, showing significant differences between layers (P<0.05). The hydrophilic of the three layers were (15.14±3.15), (13.65±2.98), and (5.32±1.87) mL/g, respectively; the hydrophilic of the bone layer was significantly lower than that of cartilage layer and middle layer (P<0.05), but no significant difference was found between cartilage layer and middle layer (P>0.05). The compression modulus of the three layers were (51.36±13.25), (47.93±12.74), and (155.18±19.62) kPa, respectively; and compression modulus of the bone layer was significantly higher than that of cartilage layer and middle layer (P<0.05), but no significant difference was found between cartilage layer and middle layer (P>0.05). The osteochondral integration of multi-layered scaffold was tightly bonded with each layer. The layer adhesive strength between the cartilage layer and the middle layer was (18.21±5.16) kPa, and the layer adhesive strength between the middle layer and the bone layer was (16.73±6.38) kPa, showing no significant difference (t=0.637, P=0.537). MTT assay showed that L929 cells grew well on the scaffolds, indicating no scaffold cytotoxicity. GFP-labeled rat BMSCs grew evenly on the scaffolds, indicating scaffold has excellent biocompatibility.ConclusionThe advantages of three layers which have different performance of the tissue engineered osteochondral integration of multi-layered scaffold is achieved double biomimetics of structure and composition, lays a foundation for further research of animal in vivo experiment, meanwhile, as an advanced and potential strategy for osteochondral defect repair.
ObjectiveTo review the advances in utilizing paracrine effect of stem cells in knee osteoarthritis (OA) treatment.MethodsThe researches in applying stem cells derived conditioned medium, extracellular matrix, exosomes, and microvesicles in knee OA treatment and cartilage repair were reviewed and analyzed.ResultsThe satisfying outcomes of using different products of stem cells paracrine effect in knee OA condition as well as cartilage defect is revealed in studies in vitro and in vivo. The mechanism including suppressing the intraarticular inflammation, the apoptosis of chondrocytes, and the degradation of cartilage matrix, while enhancing the synthesis of cartilage matrix, the differentiation of in-situ stem cells into chondrocytes and the migration to the affected area. The effectiveness can be further improved supplemented with the tissue engineering methods or gene modification.ConclusionCompared with the traditional stem cell therapy, applying the products from paracrine effect of stem cells in knee OA treatment is more economical and safer, presenting great potential in clinical practice.
ObjectiveTo investigate the differential expression of transient receptor potential vanilloid receptor 4 (TRPV4) protein in the osteoarthritis (OA) and normal cartilages, and explore the role of TRPV4 in the prevention and treatment of OA.MethodsThe cartilage tissues from the patients of knee OA (OA group) and femoral neck fracture (control group) were taken. In OA group, there were 6 males and 9 females; the age ranged from 55 to 78 years (mean, 69 years); the Kellgren-Lawrence (K-L) score was 3.0±0.8. In control group, there were 5 males and 10 females; the age ranged from 57 to 91 years (mean, 71 years). There was no significant difference in gender and age between the two groups (P>0.05). Western blot, real-time fluorescence quantitative PCR, Masson staining, and immunohistochemical staining were used to detect the difference in protein and mRNA expressions of TRPV4 between the OA and normal cartilages. Then the relationship between the K-L score of OA and the rate of TRPV4-positive cells was analyzed.ResultsThe relative expression of TRPV4 protein and mRNA in OA group were 0.454±0.199 and 2.951±1.200, which were higher than those in control group (0.165±0.074, 1.437±0.682). The difference in relative expression of TRPV4 protein was significant (t=2.718, P=0.026). Histology observation showed that the chondrocytes arranged disorderly in OA group, the structure of extracellular matrix was abnormal, and the cartilage defect reached the deep layer. There were more TRPV4-positive cells in the degenerated tissue, and the rate of TRPV4-positive cells was 37.353%±13.496%. The chondrocytes were arranged well in control group, and the rate of TRPV4-positive cells was only 9.642%±3.284%. There was a significant difference between the two groups (t=7.491, P=0.000). The rate of TRPV4-positive cells in OA group was positively correlated with the OA K-L score (r=0.775, P=0.001).ConclusionThe TRPV4 expression increased in OA cartilages that may contribute to the development of OA.
Decellularized extracellular matrix (dECM) has been widely used as a scaffold for regenerative medicine due to its high biomimetic and excellent biocompatibility. As a functional polymer material with high water content and controlled fluidity, hydrogel is very promising for some minimally invasive surgery in clinical practice. In recent years, with the rapid development of hydrogel theory and technology, dECM hydrogel has gradually become a research hotspot in the field of regenerative medicine. In this paper, the related researches in recent years are reviewed regarding the preparation of dECM hydrogel and its preclinical application. The future clinical use is also prospected.
ObjectiveTo investigate the expression of Runt-related transcription factor 1 (RUNX1) in gastric cancer and its correlation with clinicopathological features, prognosis and tumor cell invasion ability. Methods① Database analysis: the expression of RUNX1 in gastric cancer and adjacent tissues were analyzed by TCGA and GEO database. Kaplan-Meier Plotter database was used to analyze the correlation between RUNX1 expression level and overall survival (OS) of gastric cancer patients. GO analysis and KEGG pathway enrichment were used to analyze the possible functions and signaling pathways of RUNX1 in gastric cancer, and gene correlation was verified by GEPIA database. ② Clinical case validation: the cancer tissues and adjacent tissues of 62 patients with gastric cancer admitted to the Second Hospital of Lanzhou University from June 2018 to December 2019 were retrospectively collected for immunohistochemical staining, HE staining and Sirius red staining, and the relation between RUNX1 expression and clinicopathological features and prognosis of patients was explored. ③ Cell experiment: we knocked down RUNX1 by using small interfering RNA, and then analyzed the relation between RUNX1 and the invasion ability of gastric cancer cells by Transwell assay. Results① Database analysis: RUNX1 was highly expressed in gastric cancer tissues and negatively correlated with OS (P<0.001). GO analysis and KEGG pathway enrichment analysis showed that RUNX1 was not only involved in the construction of collagen in extracellular matrix (ECM), but also significantly enriched in ECM-receptor interaction pathway. The results of GEPIA gene correlation analysis showed that RUNX1 was positively correlated with gene expression involved in ECM-receptor interaction pathway (P<0.05). ② Clinical case validation: the results of immunohistochemical staining showed that RUNX1 was relatively highly expressed in gastric cancer tissues, and the high expression of RUNX1 was a risk factor affecting the postoperative OS of gastric cancer patients (RR=5.074, P=0.034); the expression of RUNX1 in gastric cancer tissues was positively correlated with red staining area of Sirius red staining (r=0.46, P<0.001). ③ Cell experiment: invasion experiments confirmed that the number of invasive AGS or HGC27 cells in si-001 group and si-002 group decreased after RUNX1 knockdown. ConclusionRUNX1 is highly expressed in gastric cancer and suggests a worse survival prognosis, and it is possible that RUNX1 promotes the development of gastric cancer by activating the ECM-receptor interaction pathway.
Survivors from myocardial infarction (MI) eventually develop heart failure due to the post-infarct ventricular remodeling which could not be suppressed by existing treatments. Currently, coronary heart disease has become the major cause of heart failure instead of rheumatic heart disease in China. For this reason, seeking effective treatment to prevent post-infarct ventricular remodeling is urgent. Intramyocardial injection of hydrogels as a new strategy for MI treatment has made great progress recently. This review discusses the principle, present status, mechanisms and prospects of injectable hydrogel therapies for MI.