Objective Extracellular matrix is one of the focus researches of the adi pose tissue engineering. To investigate the appropriate method to prepare the porcine skeletal muscle acellular matrix and to evaluate the biocompatibility of the matrix. Methods The fresh skeletal muscle tissues were harvested from healthy adult porcine and were sl iced into2-3 mm thick sheets, which were treated by hypotonic-detergent method to remove the cells from the tissue. The matrix was then examined by histology, immunohistochemistry, and scanning electron microscopy. The toxic effects of the matrix were tested by MTT. Human adi pose-derived stem cells (hADSCs) were isolated from adi pose tissue donated by patients with breast cancer, and identified by morphology, flow cytometry, and differentiation abil ity. Then, hADSCs of passage 3 were seeded into the skeletal muscle acellular matrix, and cultured in the medium. The cellular behavior was assessed by calcein-AM (CA) and propidium iodide (PI) staining at 1st, 3rd, 5th, and 7th days after culturing. Results Histology, immunohistochemistry, and scanning electron microscopy showed that the muscle fibers were removed completely with the basement membrane structure; a large number of collagenous matrix presented as regular network, porous-like structure. The cytotoxicity score of the matrix was grade 1, which meant that the matrix had good cytocompatibil ity. The CA and PI staining showed the seeded hADSCs had the potential of spread and prol iferation on the matrix. Conclusion Porcine skeletal muscle acellular matrix has good biocompatibility and a potential to be used as an ideal biomaterial scaffold for adi pose tissue engineering.
Objective To summarize applications and research progress of common magnetic resonance imaging lipid detection techniques in abdomen and pelvis. Method The latest domestic and foreign research literatures related to the applications and research progress of common magnetic resonance imaging lipid detection techniques in the abdomen and pelvis in recent years were collected and reviewed. Results The fat-selective spectral-spatial imaging, 1H-magnetic resonance spectroscopy (1H-MRS), and Dixon & IDEAL are three main magnetic resonance imaging lipid detection techniques, and they can estimate the fat content in the normal tissues and lesions noninvasively and longitudinally, which make the ectopic fat-induced diseases’ early diagnosis, treatment and follow-up possible. Conclusion Magnetic resonance imaging lipid detection techniques have obvious clinical values in quantitative measurement of fat content, and each method gets its own advantage, especially modified Dixon, which is more convenient and accurate and shows an enormous potential in clinical practice.
ObjectiveTo investigate the necessity of subcutaneous suture for gynecologic abdominal incision, and to prove the clinical value of suture without subcutaneous ligature. MethodsWe retrospectively studied the clinical data of 210 cases of gynecologic abdominal incision treated between May 2010 and May 2013. A total of 111 cases had the suture without subcutaneous ligature and 99 received the traditional suture. ResultsOne patient (0.90%) had fat liquefaction in the group of suture without subcutaneous ligature, while 7 (7.07%) of fat liquefaction were found in the traditional suture group, and the difference was statistically significant (χ2=3.883, P=0.049). No hospital infection occurred. The healing period averaged (15.1±4.7) days, and the patients were followed up for 2 months without any complication of abdominal incision in all the patients. ConclusionSuture without subcutaneous ligature is simple and easy to practice, with precise effect, which deserves clinical application.
ObjectiveTo study effect of expression levels of serum inflammatory factors and insulin receptor substrate(IRS)-1/2 in visceral adipose tissue after Roux-en-Y gastric bypass(RYGB) on type 2 diabetes mellitus(T2DM) rats, and explore possible mechanism in treatment of T2DM. MethodsThe T2DM rats models were established, which were divided into 3 groups by intervention: T2MD-RYGB group(n=14), T2MD-sham operation(T2MD-SO) group(n=10), and T2MD group(n=10), and 10 normal rats were selected as control group. The rats of the T2MD-RYGB group were received the RYGB, and of the T2MD-SO group were received transection and reanastomosis of the gastroin-testinal tract. The fasting plasma glucose(FPG), fasting insulin(FINS), C-reaction protein(CRP), tumor necrosis factor-α(TNF-α), free fatty acid(FFA), homestasis model assessment for insulin resistance(HOMA-IR), adipose tissue insulin resistance(Adipo-IR) were tested respectively before operation and on week 1, 4, 8 after operation(synchronous detec-tion of rats with or without surgical intervention). The IRS-1 and IRS-2 protein contents of the rat epididymal adipose tissue were tested on week 8 after operation. ResultsThe FPG, FINS, CRP, TNF-α, FFA levels, and HOMA-IR, Adipo-IR indexes in the T2DM rats were significantly higher than those in the normal rats(P < 0.05) before operation, the above indicators on week 4, 8 after operation were significantly lower than those before operation in the T2MD-RYGB group(P < 0.05). The differences of changes among the other groups were not statistically significant(P > 0.05). The IRS-1 and IRS-2 protein expressions in the adipose tissue of the rats were significantly increased in the T2MD-RYGB group as compared with these indicators in the T2MD group and T2MD-SO group(P < 0.05), but which were significantly lower than those in the control group(P < 0.05). ConclusionsRYGB could increase IRS-1/2 expression levels in adipose tissue, which could enhance insulin sensitivity, decrease serum inflammatory factors levels, and improve insulin resistance ultimately. This might be one of the mechanisms in treatment of T2DM.
Objective To investigate the possibility of theadipose tissue-derived stromal cells(ADSCs) to differentiate into the neuron-like cells and to explore a new cell source for the transplantation related to the central nervous system. Methods Adipose was digested by collagenase, cultured in the fetal bovine serum containing a medium. Trypse was used to digest the cells and the cell passage was performed. The 3rd to the 9th passage ADSCs were used to make an induction. Isobutylmethylxanthine, indomethacin, insulin, and dexamethasone were used to induce the ADSCs to differentiate into the neuron-like cells and adipocytes. Sudan black B and immunocytochemistry were used to identify the cells. Results A population of the ADSCs could be isolated from the adult human adipose tissue, they were processed to obtain a fibroblast-like population of the cells and could be maintained in vitro for an extendedperiod with the stable population doubling, and they were expanded as the undifferentiated cells in culture for more than 20 passages, which indicated their proliferative capacity. They expressed vimentin and nestin, and characteristics of the neuron precursor stem cells at an early stage of differentiation. And the majority of the ADSCs also expressed the neuron-specific enolase and βⅢ-tubulin, characteristics of the neurons. Isobutyl-methyxanthine, indomethacin, insulin, and dexamethasone induced 40%-50% of ADSCs to differentiate into adipocytes and 0.1%0.2% of ADSCs into neuron-like cells. The neuron-like cells had a complicated morphology of the neurons, and they exhibited a neuron phenotype, expressed nestin, vimentin, neuron-specific enolase and βⅢ-tubulin, but some neuron-like cells also expressed thesmooth muscle actin (SMA), and the characteristics of the smooth muscle cells; however, the neurons from the central nervous system were never reported to express this kind of protein. Therefore, the neuron-like cells from the ADSCs could be regarded as functional neurons. Conclusion Ourresults support the hypothesis that the adult adipose tissue contains the stem cells capable of differentiating into the neuron-like cells, and they can overcome their mesenchymal commitment, which represents an alternative autologous stemcell source for transplantation related to the central nervous system.
Objective Seed cells are the hotspot of tissue engineering research. To study the seed cells with high potential of adipogenic differentiation for applying the adipose tissue engineering and increasing the constructing efficiency of adipose tissue engineering. Methods Mature adipocytes (MA) and adipose-derived stromal cells (ADSCs) were harvestedfrom human fat aspirates via l iposuction by collagenase digestion. MA were cultured and induced to dedifferentiated adipocytes (DA) by ceil ing adherent culture method. DA and ADSCs were induced to adipogenic differentiation. The adipogenic abil ities of DA and ADSCs were compared by inverted phase contrast microscope observation, absorption spectrometry assay of oil red O staining, and cell counting of oil red O staining. Results MA could dedifferentiate into fibroblast-shaped DA. After adi pogenic differentiation, the inverted phase contrast microscope observation showed that there were much more l i pid droplet in DA than in ADSCs. Absorption spectrometry assay of oil red O staining showed there were significant l ipid droplet aggregation in DA 4 days of adipogenic induction. However, the same phenomenon could be observed in ADSCs at 10 days after differentiation. After 12 days, the absorption value of DA was higher than that of ADSCs, showing significant difference (P lt; 0.05). The cell counting of oil red O staining demonstrated that the adipogenic rates of DA and ADSCs were 65% ± 6% and 35% ± 5%, respectively, showing significant difference (P lt; 0.05). Conclusion The potential of adipogenic differentiation of DA is ber than that of ADSCs. DA is a promising seed cell of adipose tissue engineering.
ObjectiveTo summarize the isolation procedures, molecular characterization, and differentiation and vascularization capacity of adipose-derived stem cells (ADSCs), in order to discuss the potential value of ADSCs for the repairment and regeneration of adipose tissues. MethodsRelated literatures about ADSCs were retrieved to summarize the potential value of ADSCs for the repairment and regeneration of adipose tissues. ResultsAs mesenchymal stem cells, ADSCs was rich in human adipose tissues. ADSCs possessed the potential to differentiate toward a variety of cell lineages, such as adipogenic, chondrogenic, osteogenic, cardiomyogenic, myogenic, and angiogenic. Besides, its capacity of adipogenic differentiation could maintain several passages. The most importantly, ADSCs could secrete significant amounts of angiogenesis-related cytokines, such as vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF-2), which increased the angiogenesis of adipose tissue. ConclusionsADSCs play a key role in adipose tissue engineering, autologous adipose tissue grafting, and soft tissue wound repairing, which have important application prospect for breast reconstruction.
ObjectiveTo evaluate the mechanism of stromal vascular fraction (SVF) promoting angiogenesis and tissue regeneration in tissue engineering chamber. MethodsTwenty-four 6-month-old New Zealand white rabbits, male or female, weighing 2.5-2.8 kg, were selected. Thoracic dorsal arteriovenous bundle combined with collagen type I scaffold was transplanted to dorsal side, and wrapped by cylindrical hollow silicone chamber; all animals were randomly divided into the experimental group (n=12) and the control group (n=12). SVF was isolated from the back fat pads of rabbits in experimental group and labelled with DiI at 2 weeks after operation. The 1 mL cell suspension (1×106 cells/mL) and equal saline were injected into the chamber in experimental group and control group, respectively. The regenerative tissues were harvested for general observation and HE staining at 2 and 4 weeks after injection;and immunofluorescent staining was carried out in experimental group at 4 weeks. ResultsAt 2 weeks after injection, the regenerative tissue was cylindrical; obvious vessel network and incompletely degradable collagen scaffold could be seen on the surface of the new tissue in 2 groups. The volume of new tissue was (0.87±0.11) mL in experimental group, and (0.72±0.08) mL in control group at 2 weeks, showing significant difference (t=2.701, P=0.011). At 4 weeks, little collagen scaffold could be seen on the surface in control group, but no collagen scaffold in experimental group; the volume of new tissue was (0.74±0.14) mL in experimental group, and (0.64±0.10) mL in control group, showing no significant difference (t=1.424, P=0.093). HE staining showed new mature vessels at 4 weeks, but no adipose tissue or fat lobulus formed in both groups; the capillary density was significantly higher in experimental group than in control group at 2 weeks (t=6.291, P=0.000) and at 4 weeks (t=5.445, P=0.000). The immunofluorescent staining found that SVF survived and located at the edge area after 4 weeks; the expressions of CD31 and DiI were positive in some endothelial cells. ConclusionSVF can promote the angiogenesis and tissue regeneration in tissue engineering chamber, but it can not differentiate into adipocyte spontaneously without adipogenic microenvironment.
ObjectiveTo investigate the effect of burn on brown adipose tissue (BAT) in BALB/c mice. MethodsForty 3-4 months old male BALB/c mice with initial body weight of (20±3) g were randomly divided into control group and burn group (n=20).BALB/c mice in burn group were subjected to a 30% total body surface area (TBSA) full-thickness thermal injury.BALB/c mice in control group were not treated.The body weight and temperature were observed before and after burn.At 7 days after burn,morphological changes of white adipose tissue (WAT) and BAT were observed,the gene and protein expressions of uncoupling protein 1 (UCP-1) were detected. ResultsThere was no significant difference in the body weight and body temperature before burn (P>0.05).At 1,2,3,and 4 weeks after burn,the body weight was significantly lower in burn group than in control group (P<0.05).At 1,2,3,and 7 days after burn,the body temperature was significantly higher in burn group than in control group (P<0.05).At 7 days after burn,the weight of WAT was significantly reduced,and the weight of BAT was significantly increased in burn group (P<0.05); WAT and BAT cells became smaller,cell number increased,the cytoplasm and mitochondria appeared as compact.The UCP-1 gene and protein expressions of burn group were significantly higher than those of control group (P<0.05). ConclusionBAT plays an important role in burn-induced hypermetabolism.
ObjectiveTo summarize recent progress in adipose tissue acting as a more efficient and ideal therapy to facilitate wound repair and evaluate the therapeutic values of adipose tissue.MethodsThe related literature about adipose tissue for wound healing in recent years was reviewed and analyzed.ResultsEnormous studies focus on the capacity of adipose tissue to accelerate wound healing including cellular components, extracellular matrix, and paracrine signaling have been investigated.ConclusionAdipose tissue has generated great interest in recent years because of unique advantages such as abundant and accessible source, thriven potential to enhance the regeneration and repair of damaged tissue. However, there is still a need to explore the mechanism that adipose tissue regulates cellular function and tissue regeneration in order to facilitate clinical application of adipose tissue in wound healing.