miR-758-3p/ILK signaling modulated angiogenesis by regulating VEGFA in wound healing.

Chronic wounds cause physical, psychological and economic damage to patients, while therapeutic choices are limited. ILK was reported to play key roles in both fibrosis and angiogenesis, which are two important factors during wound healing. However, the function of ILK during vascularization in wounds remains unclear. In our study, we found increased ILK expression in chronic wound tissues compared to adjacent tissue, as well as a positive relationship between ILK expression and microvessel density. Moreover, fibroblasts overexpressing ILK showed an enhanced ability to promote HUVEC migration and tube formation, during which PI3K/Akt, downstream of ILK, played key roles and VEGFA was the key cytokine. Considering the important function of ILK in wound healing and the lack of an ILK activator, we investigated microRNAs targeting ILK and found that miR-758-3p could target ILK to regulate its transcription. The inhibition of miR-758-3p increased ILK expression and sequentially upregulated VEGFA and activated angiogenesis in vivo and in vitro. Taken together, these results revealed that ILK played a key role in wound healing by regulating angiogenesis and that activating ILK by inhibiting miR-758-3p was an effective way to promote wound healing. Whether miR-758-3p/ILK signaling can be utilized as a therapeutic target for wound healing requires further investigation.

Morphological operation-based bi-dimensional empirical mode decomposition for automatic background removal of fringe patterns.

A modified bi-dimensional empirical mode decomposition (BEMD) method is proposed for sparsely decomposing a fringe pattern into two components, namely, a single intrinsic mode function (IMF) and a residue. The main idea of this method is a modified sifting process which employs morphological operations to detect ridges and troughs of the fringes, and uses weighted moving average algorithm to estimate envelopes of the IMF, replacing respective local extrema detection and envelope interpolation of conventional BEMDs. The background intensity of the fringe pattern is automatically removed by extracting the single IMF, thereby relieving the mode mixing problem of the BEMDs. A fast algorithm based on 2D convolution is also presented for reducing the calculation time to several seconds only. This approach is applied to process simulated and real fringe patterns, and the results obtained are compared with Fourier transform, discrete wavelet transform, and other EMD methods. The MATLAB code is downloadable at http://gr.xjtu.edu.cn/web/zhouxiang.

Proteomic analysis of mitochondria from infantile hemangioma endothelial cells treated with sodium morrhuate and its liposomal formulation.

Hemangioma is the most common benign tumor of infancy. The aim of this study is to evaluate the biological effects of sodium morrhuate (SM) and its liposomal formulation on infantile hemangioma endothelial cells (IHECs). Morphological analysis revealed that exposure to liposomal sodium morrhuate (LSM) preferentially caused apoptotic death in IHECs, manifested as shrunken configuration and formation of apoptotic bodies. In contrast, necrotic death was prominent in IHECs treated with an equal concentration of SM. By means of proteomic analysis and confirmation experiments, we revealed that the apoptosis-inducing effects of LSM were associated with an upregulation of a set of genes involved in mitochondrial death pathway, including apoptosis-inducing factor, cytochrome c1, caspase-8, and lamin B1. In conclusion, our data highlight the proapoptotic activity of LSM in IHECs through the mitochondrial apoptotic pathway and may provide a promising avenue to treat hemangiomas of infancy.

Lentivirus-mediated knockdown of aggrecanase-1 and -2 promotes chondrocyte-engineered cartilage formation in vitro.

Chondrocyte-based tissue engineering has emerged as a promising approach for repair of injured cartilage tissues that have a poor self-healing capacity. However, this technique faces a major limitation: dedifferentiation of chondrocytes occurs following several passages in culture. Aggrecan, a major component of cartilage extracellular matrix, plays an essential role in chondrocyte differentiation. The aim of this study is to determine whether inhibition of chondrocyte aggrecanases, key degradative enzymes for aggrecan in cartilage, could benefit chondrocyte differentiation and the preservation of chondrocyte phenotype within a long-term period. Lentivirus-mediated RNA interference (RNAi) was employed to target both aggrecanase-1 and -2 in primary rat chondrocytes, and the transduced cells were seeded into chitosan-gelatin three-dimensional scaffolds. Histological, morphological, and biochemical analyses were performed at 1-8 weeks post-implantation to study chondrocyte survival, differentiation, and function. We found that lentivirus-mediated RNAi notably decreased the abundance of aggrecanase transcripts in chondrocytes but did not affect cell viability. Most importantly, compared to the control constructs seeded with untransduced chondrocytes, the aggrecanase inhibition increased chondrocyte proliferation and reinforced the production of glycosaminoglycans and total collagen, indicative of chondrocyte differentiation. The mRNA expression of chondrocyte marker genes (collagen II and aggrecan) was enhanced by aggrecanase silencing relative to the control. Together our data demonstrate that inhibition of endogenous aggrecanases facilitates chondrocyte differentiation and chondrocyte-engineered cartilage formation in vitro. The combination of lentiviral delivery system and genetic manipulation techniques provides a useful tool for modulation of chondrocyte phenotype in cartilage engineering.

Cartilage tissue engineering with demineralized bone matrix gelatin and fibrin glue hybrid scaffold: an in vitro study.

To develop a cartilage-like tissue with hybrid scaffolds of demineralized bone matrix gelatin (BMG) and fibrin, rabbit chondrocytes were cultured on hybrid fibrin/BMG scaffolds in vitro. BMG scaffolds were carefully soaked in a chondrocyte-fibrin suspension, which was polymerized by submerging the constructs into thrombin-calcium chloride solution. Engineered cartilage-like tissue grown on the scaffolds was characterized by histology, immunolocalization, scanning electron microscopy, biochemical assays, and analysis of gene expression at different time points of the in vitro culture. The presence of proteoglycan in the fibrin/BMG hybrid constructs was confirmed by positive toluidine blue and alcian blue staining. Collagen type II exhibited intense immunopositivity at the pericellular matrices. Chondrogenic properties were further demonstrated by the expression of gene-encoded cartilage-specific markers, collagen type II, and aggrecan core protein. The glycosaminoglycan production and hydroxyproline content of tissue grown on the fibrin/BMG hybrid scaffolds were higher than that of the BMG group. In conclusion, the fibrin/BMG hybrid scaffolds may serve as a potential cell delivery vehicle and a structural basis for cartilage tissue engineering.

Aggrecanases gene inhibition in chondrocytes: a new possible strategy to relieve immune rejection of transplants.

Cartilage damaged by trauma or degenerative disease has limited intrinsic potential for repair, due to lack of blood supply. The repair and reconstruction of cartilage defects are severe problems, and many patients are eager to find avenues to these matters. Until now, the number of methods used to repair cartilage defects has increased, but all of these have their own advantages and inconveniences, and do not seem to have been optimized. As the source of autologous cartilage is limited and has a high potential donor site morbidity, it is common practice to transplant allogenic cartilage instead. However, immunological rejection will happen accompanied with allogenic cartilage transplantation, affect the long viability of cartilage and result in the absorption of cartilage. Cartilage is an avascular tissue and its extracellular matrix prevents immunization of the host. The extracellular matrix acts as immunological barrier and makes the cartilage be a poor antigen tissue. So it is important to maintain the stability of cartilage matrix. The main features are the loss of aggrecan after cartilage transplantation surgery and aggrecanases play an important role in the cartilage degradation of aggrecan. We hypothesize that if we inhibit the aggrecanases gene of chondrocytes, make the extracellular matrix aggrecan of chondrocytes increasing and immunological rejection problems will be relieved. Accordingly, this will provide a new method for allogenic and tissue engineering cartilage transplantation and cartilage transplantation will be utilized widely for any clinical treatments.

MiR-152-3p regulates cell proliferation, invasion and extracellular matrix expression through by targeting FOXF1 in keloid fibroblasts.

Emerging evidence has revealed that microRNAs (miRNAs) play critical roles in keloid pathogenesis. However, potential molecular mechanism of keloid formation remains unclear. In the present study, our findings showed that miR-152-3p mRNA expression level was notably up-regulated in keloid tissues and keloid fibroblasts compared with that of normal skin tissues and normal skin fibroblasts, respectively. Furthermore, miR-152-3p inhibition remarkably suppressed cell proliferation, which was increased by miR-152-3p overexpression. Cell invasion was also significantly decreased by miR-152-3p inhibition, whereas was increased by miR-152-3p overexpression. The mRNA and protein expression levels of extracellular matrix components including type I collagen, type III collagen and fibronectin were decreased by miR-152-3p inhibition, but were increased by miR-152-3p overexpression. In addition, results of dual-luciferase reporter assay indicated that FOXF1 is a direct target of miR-152-3p. FOXF1 overexpression significantly inhibits cell proliferation, invasion, and extracellular matrix in keloid fibroblasts, and the suppressive effects of miR-152-3p mimic on these functions were notably partly reversed by FOXF1 overexpression. Taken together, these findings indicated that miR-152-3p regulates cell proliferation, invasion and extracellular matrix expression through targeting FOXF1 in keloid fibroblasts, suggesting that miR-152-3p is a novel and promising molecular target for keloid treatment.

Effects of RNAi-mediated inhibition of aggrecanase-1 and aggrecanase-2 on rat costochondral chondrocytes in vitro.

AIM: Failure of transplanted cartilage or allogenic chondrocytes is attributed mainly to immunological rejection and cartilage degradation. A major feature is the loss of aggrecan from the cartilage matrix, primarily due to the action of the specific proteinases aggrecanase-1 and aggrecanase-2. The aim of this in vitro study was to determine whether the specific inhibition of aggrecanase-1 and aggrecanase-2 by RNAi would mitigate aggrecan loss from cultured chondrocytes. METHODS: Expression plasmid vectors of shRNA targeting aggrecanase-1 and aggrecanase-2 were constructed and transfected into cultured rattus costochondral chondrocytes. The transfected cells were induced with interleukin-1beta (IL-1beta). Gene mRNA levels were analyzed by RT-PCR. Aggrecan and collagen II content were measured by immunohistochemistry and Western blotting. RESULTS: As the chondrocytes underwent dedifferentiation, aggrecanase-1 increased significantly. The specific inhibition of aggrecanase-1 and aggrecanase-2 by RNAi had no negative effect on the morphology and growth velocity of the chondrocytes. The mRNA of aggrecanase-1 and aggrecanase-2 decreased significantly. The alpha-2-macroglobulin expression level was increased by the shRNA specific for aggrecanase-1. Other genes of the chondrocytic extracellular matrix were not affected. RNAi significantly increased the aggrecan and collagen II content of chondrocytes treated with IL-1beta. CONCLUSION: The results suggest that inhibition of aggrecanase-1 and aggrecanase-2 by RNAi can mitigate aggrecan degradation, without interfering with chondrocytic gene phenotype recovery. RNAi technology can be a useful tool for studying degenerative processes in cartilage.

Delivery of sodium morrhuate to hemangioma endothelial cells using immunoliposomes conjugated with anti-VEGFR2/KDR antibody.

Hemangioma is a common benign tumor affecting infants. In this study, we prepared sodium morrhuate immunoliposomes through encapsulation of sodium morrhuate with liposomes coupled with an anti-VEGFR2/KDR antibody and examined its effect on the biology of human hemangioma endothelial cells (HECs). It was found that compared to the liposomal sodium morrhuate group, treatment with sodium morrhuate immunoliposomes facilitated cell detachment and apoptotic death. Confocal microscopy analysis revealed that sodium morrhuate immunoliposomes had a higher binding activity to HECs than liposomal sodium morrhuate. Apoptosis analysis further demonstrated that treatment with liposomal sodium morrhuate or sodium morrhuate immunoliposomes significantly induced apoptosis in HECs, compared to the control group. Western blot analysis revealed an induction of caspase-3 and caspase-9 levels and reduction of caspase-8 and Bcl-2 levels in HECs treated with liposomal sodium morrhuate or sodium morrhuate immunoliposomes. Taken together, these results indicate that sodium morrhuate immunoliposomes have an increased capacity to target HECs and promote mitochondrial apoptosis. Therefore, sodium morrhuate immunoliposomes may represent a promising agent in the treatment of hemangiomas.

[The mechanical force analysis of cleft maxillary three dimensional finite element models after alveolar bone graft].

To investigate the biomechanical influences on two different cleft maxillary 3D finite element models pre- and post-alveolar bone graft, we developed a cleft palate bony model from a 17 year cleft palate male CT scan data and built an alveolar bone-grafted cleft maxillary 3D finite element model through gluing the graft model. Apply vector lip force on the anterior face of the models. Study the press (including S3 principal, S1 principal, von Mises and shear) distribution properties and localized area. The results suggested that the press principal spreads along the alveolar ridge and formed several focused areas. After bone grafted, the shear stress tends to be evenly. The grafted alveolar could resist the medially deformation of alveolar crest and the shear stress to the nasal base bony structure. The conclusions from results demonstrated that the deformation of alveolar ridge is possibly due to the lip pressure after the lip repair. The shear stress along the alveolar ridge could cause the severity of the dentition. The grafted bony structure could even the shear stress distribution evenly other than the distribution properties.

Experimental study of tissue-engineered cartilage allograft with RNAi chondrocytes in vivo.

PURPOSE: To determine the effects of RNA interference (RNAi) on chondrocyte proliferation, function, and immunological rejection after allogenic tissue-engineered cartilage transplantation within bone matrix gelatin scaffolds. METHODS: Seven million rat normal and RNAi chondrocytes were harvested and separately composited with fibrin glue to make the cell suspension, and then transplanted subcutaneously into the back of Sprague Dawley rats after being cultured for 10 days in vitro. Untransplanted animals served as the control group. The allograft and immunological response were examined at 1, 2, 4, 8, and 12 months postoperatively with hematoxylin and eosin histochemical staining, immunohistochemical staining (aggrecan, type II collagen, class I and II major histocompatibility complex), and flow cytometry for peripheral blood cluster of differentiation 4(+) (CD4(+)) and CD8(+) T-cells. RESULTS: There was no infection or death in the rats except one, which died in the first week. Compared to the control group, the RNAi group had fewer eukomonocytes infiltrated, which were only distributed around the graft. The ratio of CD4(+)/CD8(+) T-cells in the RNAi group was significantly lower than the normal one (P<0.05). There were many more positively stained chondrocytes and positively stained areas around the cells in the RNAi group, which were not found in the control group. CONCLUSION: The aggrecanase-1 and aggrecanase-2 RNAi for chondrocytes decreased the immunological rejection effect.

Copolymer cell/scaffold constructs for bone tissue engineering: co-culture of low ratios of human endothelial and osteoblast-like cells in a dynamic culture system.

The aim of this study was to compare the effect of different ratios of human umbilical vein endothelial cells (HUVECs) on osteogenic activity of human osteoblast-like cells (HOB) and capillary-like structure (CLS), seeded into copolymer scaffolds in a dynamic culture system. HOB and HUVEC were co-cultured into poly(L-lactide)-co-(1,5-dioxepan-2-one) [poly(LLA-co-DXO)] scaffolds at ratios of 5:1 (5:1 group) and 2:1 (2:1 group). Samples were collected after 5, 15, and 25 days. Cross-sections were processed and the CLS from HUVEC was disclosed in both groups. Cell viability was determined by dsDNA assay. Cells seeded at the ratio of 5:1 had good viability. Total RNA was isolated and the reverse transcription reaction was performed. The influences on the expression of several osteogenic genes were various with regarding to different ratios of HUVEC demonstrated by the PCR array. The RT-PCR results was in consistent with the PCR array results that several osteogenesis related genes had higher expression in the 5:1 group than in the 2:1 group, especially at day 25, such as alkaline phosphatase, insulin-like growth factor 1 (IGF1), and so forth. ELISA showed that the production of IGF1 after 25 days of incubation were higher in cells co-cultured at the 5:1 ratio than at the 2:1 ratio. The results show that under dynamic culture conditions, co-culture of HOB with a low ratio of HUVEC in copolymer scaffolds results in CLS formation and significantly influenced the expression of osteogenic markers.

Comparison of short-run cell seeding methods for poly(L-lactide-co-1,5-dioxepan-2-one) scaffold intended for bone tissue engineering.

Constructs intended for bone tissue engineering are influenced by the initial cell seeding procedure. The seeding method should be rapid, convenient, improve cell spatial distribution, and have no negative effects on cellular viability and differentiation. This study aimed to compare the effect of short-run seeding methods (centrifuge and vortex) with a static method on the scaffolds prepared from poly(L-lactide-co-1,5-dioxepan-2-one) by solvent-casting particulate-leaching (SCPL) technique. Human osteoblast-like cells (HOB) were seeded by the three methods described above. The seeding efficiency was determined by attached cell numbers. Cellular proliferation was analyzed by WST-1 and dsDNA assay. Cell distribution was examined by scanning electron (SEM) and fluorescence microscopy. Expression of alkaline phosphatase (ALP), collagen type I (Col I), osteocalcin (OC) and proliferating cell nuclear antigen (PCNA) were determined by real time RT-PCR. Results indicated that centrifuge and vortex increased seeding efficiency and had no negative effects on cellular viability. The data obtained by the fluorescence microscope confirmed the SEM results that the vortex method improved cell distribution through the scaffolds more than the other two methods (p<0.05). The RT-PCR results showed no significant differences on the expression of mRNA between the three methods of the above markers. The vortex method was found to be a simple and feasible seeding method for the poly(L-lactide-co-1,5-dioxepan-2-one) scaffolds.

Fluorine-induced apoptosis and lipid peroxidation in human hair follicles in vitro.

Fluoride is an essential trace element for human body; however, exposure to high amounts of fluoride has been documented to be correlated with an increasing risk of hair loss. To date, little is known about the mechanism(s) of how fluoride affects hair follicles. Here, we demonstrated that middle (1.0 mmol/L) and high (10.0 mmol/L) concentrations of sodium fluoride (NaF) significantly inhibited hair follicle elongation in vitro, but low NaF (0.1 mmol/L) showed little influence. Moreover, treatment with high levels of NaF resulted in a marked increase in terminal dUTP nick end labeling-positive cells in the outer layer of the outer root sheath, the dermal sheath, and the lower bulb matrix surrounding dermal papilla. Furthermore, the enhanced apoptosis was coupled with an increased oxidative stress manifested as higher malondialdehyde content. Additionally, the presence of selenium considerably antagonized the effects of middle NaF on hair follicles, with regard to either the suppression of hair growth or the induction of oxidative stress and apoptosis. In conclusion, exposure to high levels of fluoride compromises hair follicle growth and accelerate cell apoptosis in vitro. The toxicity of fluoride can be reduced by selenium, at least partially via the suppression of intracellular oxidative stress.

[Effects of RNA interference against aggrecanase 1 gene on extracellular matrix metabolism of cultured chondrocytes in vitro].

OBJECTIVE: To study the effect of RNA interference (RNAi)-mediated aggrecanase-1 gene silencing on extracellular matrix metabolism of cultured rat costochondral chondrocytes. METHODS: Rat costochondral chondrocyte monolayers were obtained by microdissection and digestion. The growth and morphological changes of the chondrocytes were observed after RNAi of aggrecanase-1 gene. The mRNA expression of aggrecanase-1 was detected by RT-PCR method, and aggrecan content was determined by Western blotting. RESULTS: The specific inhibition of aggrecanase-1 by RNAi produced no adverse effect on the morphology and growth of the chondrocytes. The mRNA of aggrecanase-1 decreased and aggrecan content increased significantly after transfection of the chondrocytes. CONCLUSION: Inhibition of aggrecanase-1 decreases aggrecan degradation in cultured rat chondrocytes. RNAi technique can be a useful means for studying extracellular matrix metabolism in the cartilage.

[Study of immunolipo-sodium morrhuate applied on human hemangioma endothelial cells in vitro].

PURPOSE: To explore the method of preparing immunolipo-sodium morrhuate and evaluate its effect on human hemangioma endothelial cells in vitro. METHODS: Using SPDP((N-Succinimidyl-3-(2-pyridyldithio)) propionate) as cross-linker, anti-VEGFR2/KDR monoclone antibody was combined to the liposome surface to prepare immunolipo-sodium morrhuate by extruding method, and then its effect on human hemangioma endothelial cells in vitro was observed by laser scanning confocal microscope, inverted microscope, Gimsa staining, transmission electron microscope, MTT and flow cytometry. RESULTS: The average diameter of the immunoliposome was 122.9 nm, which had a very good stability when compared with normal liposome, it had stronger and faster combining ability, its potential to induce apoptosis was much more prominent, and its toxic effect on human hemangioma endothelial cells was gentle, which was similar to normal liposome. CONCLUSION: We have prepared immunolipo-sodium morrhuate successfully, which has very good specific initiative targetting ability in vitro and can induce pervasive apoptosis of human hemangioma endothelial cells.

[The effect of aloesin on melanocytes in the pigmented skin equivalent model].

OBJECTIVE: To observe the effect of aloesin, tea polyphenols, arbutin on melanocytes in the pigmented skin equivalent model. METHODS: First, we constructed the pigmented skin equivalent model in vitro. And then we detected the effect of aloesin, tea polyphenols and arbutin on the cells' shape, tyrosinase activity and formation of melanin in the constructed pigmented skin equivalent. RESULTS: Three depigmenting agents showed an inhibition effect on the tyrosinase activity of melanocytes and reduced significantly melanin content in the pigmented skin equivalent model, in which the tea polyphenols had the strongest effect, and then was the aloesin. But the tea polyphenols showed the strongest toxicity, while the aloesin and arbutin had a much lower toxicity. CONCLUSIONS: All the three depigmenting agents showed a concentration dependent suppression effect on the tyrosinase activity and formation of melanin, in which the tea polyphenols was the strongest effect( P <0.05). Aoesin has a good suppression effect on the tyrosinase activity and formation of melanin, but has a much lower toxicity, which could be used as a safe depigmenting agent.

[Three-dimensional finite element analysis of three conjunctive methods of free iliac bone graft for established mandibular body defects].

OBJECTIVE: To analyze the stress and displacement distribution of 3D-FE models in three conjunctive methods of vascularized iliac bone graft for established mandibular body defects. METHODS: Using computer image process technique, a series of spiral CT images were put into Ansys preprocess programe to establish three 3D-FE models of different conjunctions. RESULTS: The three 3D-FE models of established mandibular body defects by vascularized iliac bone graft were built up. The distribution of Von Mises stress and displacement around mandibular segment, grafted ilium, plates and screws was obtained. CONCLUSION: It may be determined successfully that the optimal conjunctive shape be the on-lay conjunction.

[The experimental study of lipo-sodium morrhuate promoting apoptosis of ECV-304 cells].

OBJECTIVE: To evaluate the effect of lipo-sodium morrhuate on ECV-304 cell line. METHODS: The effect lipo-sodium morrhuate was evaluated by toxicology trial (MTT), electron microscope, DNA electrophoresis and flow cytometer. RESULTS: The toxicology results showed, that the number of vital cells in lipo-sodium morrhuate group decreased slowly. The electron microscope exhibited apoptosis in the lipo-sodium morrhuate group. And there were typical DNA ladder in DNA electrophoresis and typical apoptosis peak in flow cytometer. The apoptosis rate was 22.23%. CONCLUSIONS: Unlike the normal preparation of sodium morrhuate, lipo-sodium morrhuate could induce apoptosis of ECV-304 cell line.

[Apoptotic study on the effect of fluorine and selenium on the human hair follicle in vitro].

OBJECTIVE: The aim of this study was to observe the human hair follicle apoptosis status affected by fluorine and the antagonism effect by selenium in vitro. METHODS: The single hair follicles were separated and cultured, then they were added in different concentrations of sodium fluoride and sodium selenite. Chosen the appropriate concentrations, they were divided into 7 groups. The TUNEL was used to investigate the apoptotic cells of different parts. The morphous of hair follicles was observed consecutively and electron microscope was used. RESULTS: We found that in 1 mmol/L and 10 mmol/L sodium fluoride groups, when the human hair follicles in vitro were cultured on the 5th day, the apoptotic cells of outer root sheath (ORS), dermal sheath and hair papilla, hair bulb were obviously increased. But 0.01 mmol/L sodium selenite weakened the toxicity of 1 mmol/L sodium fluoride at the outer root sheath and hair bulb (P < 0.05). CONCLUSIONS: Different concentrations of sodium fluoride had different effect on the growth of human hair follicle in vitro which were cultured on 5th day. Sodium fluoride of certain concentration could accelerate the apoptosis of human hair follicle in vitro. Sodium selenite of certain concentration could act antagonism to the toxicity of sodium fluoride.