ObjectiveTo review the research progress of constructing injectable tissue engineered adipose tissue by adipose-derived stem cells (ADSCs). MethodsRecent literature about ADSCs composite three-dimensional scaffold to construct injectable tissue engineered adipose tissue is summarized, mainly on the characteristics of ADSCs, innovation of injectable scaffold, and methods to promote blood supply. ResultsADSCs have a sufficient amount and powerful ability such as secretion, excellent compatibility with injectable scaffold, plus with methods of promoting blood supply, which can build forms of injectable tissue engineered adipose tissue. ConclusionIn despite of many problems to be dealt with, ADSCs constructing injectable tissue engineered adipose tissue may provide a promising source for soft-tissue defect repair and plastic surgery.
ObjectiveTo evaluate the effect of using Schwann-like cells derived from human umbilical cord blood mesenchymal stem cells (hUCBMSCs) as the seed cells to repair large sciatic nerve defect in rats so as to provide the experimental evidence for clinical application of hUCBMSCs. MethodsFourty-five male Sprague Dawley (SD) rats in SPF grade, weighing 200-250 g, were selected. The hUCBMSCs were harvested and cultured from umbilical cord blood using lymphocyte separating and high molecular weight hydroxyethyl starch, and then was identified. The hUCBMSCs of 3rd generation were induced to Schwann-like cells, and then was identified by chemical derivatization combined with cytokine. The acellular nerve basal membrane conduit was prepared as scaffold material by the sciatic nerve of SD rats through repeated freezing, thawing, and washing. The tissue engineered nerve was prepared after 7 days of culturing Schwann-like cells (1×107 cells/mL) on the acellular nerve basal membrane conduit using the multi-point injection. The 15 mm sciatic nerve defect model was established in 30 male SD rats, which were randomly divided into 3 groups (10 rats each group). Defect was repaired with tissue engineered nerve in group A, with acellular nerve basal membrane conduit in group B, and with autologous sciatic nerve in group C. The nerve repair was evaluated through general observation, sciatic function index (SFI), nerve electrophysiology, weight of gastrocnemius muscle, and Masson staining after operation. ResultsThe hUCBMSCs showed higher expression of surface markers of mesenchymal stem cells, and Schwann-like cells showed positive expression of glia cell specific markers such as S100b, glial fibrillary acidic protein, and P75. At 8 weeks after operation, the acellular nerve basal membrane conduit had no necrosis and liquefaction, with mild adhesion, soft texture, and good continuity at nerve anastomosis site in group A; group B had similar appearance to group A; adhesion of group C was milder than that of groups A and B, with smooth anastomotic stoma and no enlargement, and the color was similar to that of normal nerve. SFI were gradually decreased, group C was significantly greater than groups A and B, group A was significantly greater than group B (P<0.05). The compound action potential could be detected in anastomotic site of 3 groups, group C was significantly greater than groups A and B, and group A was significantly greater than group B in amplitude and conduction velocity (P<0.05). Atrophy was observed in the gastrocnemius of 3 groups; wet weight's recovery rate of the gastrocnemius of group C was significantly greater than that of groups A and B, and group A was significantly greater than group B (P<0.05). Masson staining showed that large nerve fibers regeneration was found in group A, which had dense and neat arrangement with similar fiber diameter. The density and diameter of medullated fibers, thickness of myelinated axon, and axon diameter of group C were significantly greater than those of groups A and B, and group A was significantly greater than group B (P<0.05). ConclusionTissue engineered nerves from hUCBMSCs-derived Schwann-like cells can effectively repair large defects of the sciatic nerve. hUCBMSCs-derived Schwann-like cells can be used as a source of seed cells in nerve tissue engineering.
ObjectiveTo investigate the effect of cytoskeleton modification on the adipogenic differentiation of rat Achilles-derived tendon stem cells (TSCs) in vitro. MethodsTSCs were isolated from the tendon tissue of male Sprague Dawley rats (aged 3 weeks) by enzymatic digestion method and cultured for 3 passages. After the 3rd passage cells were cultured with DMEM medium containing 15% fetal bovine serum and cytochalasin D (CYD) at the concentrations of 0, 50, 100, 500, and 1 000 ng/mL, the cell survival condition and morphology changes were observed by inverted phase contrast microscope, the cytoskeleton was observed through fibrous actin (F-actin) staining, and the ratio of F-actin/soluble globular actin (G-actin) was detected and calculated through Western blot. According to the above results, the effective concentration of CYD was selected and used for next experiments. After TSCs were cultured for 3 and 7 days respectively with adipogenic induction media (induction group), adipogenic induction media containing CYD (CYD+induction group), ordinary medium (ordinary group), and ordinary medium containing CYD (CYD+ordinary group), the real-time quantitative PCR (qRT-PCR) and Western blot were carried out to measure the mRNA and protein expressions of adipogenic differentiation-related markers, including peroxisome proliferator-activated receptor γ (PPARγ), 1ipoprotein lipase (LPL), and fatty acid binding protein (aP2). ResultsThe final CYD concentration of 100 ng/mL can inhibit effectively G-actin polymerization into F-actin, but could not affect TSCs survival, which was used for next experiments. qRT-PCR and Western blot suggested that the mRNA expressions of PPARγ, LPL, and aP2 and the protein expressions of PPARγ and aP2 were increased significantly in the CYD+induction group at 3 and 7 days when compared with the induction group (P<0.05). In the CYD+ordinary group, there still was a significant increase in the mRNA expressions of PPARγ, LPL, and aP2 when compared with the ordinary group (P<0.05). ConclusionInhibition of F-actin polymerization can increase adipogenic differentiation of rat Achilles-derived TSCs in vitro, and cytoskeleton modification is a pre-requisite for TSCs differentiation into adipocytes, which might have important implications for the mechanism research of tendinopathy.
ObjectiveTo evaluate the effect of leucocyte- and platelet-rich plasma (L-PRP) on the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in treating avascular necrosis of the femoral head (ANFH) in rabbits. MethodsTwenty-four New Zealand white rabbits (4-6 months old, both genders, weighing 2.0-3.0 kg) were used for the establishment of bilateral ANFH models and divided into 4 groups (n=6). BMSCs were isolated from the bone marrow of iliac crest, cultured and identified. L-PRP was prepared by Landesberg method. Core decompression only (group A), core decompression and L-PRP implantation (group B), core decompression and BMSCs implantation (group C), and core decompression and implantation of BMSCs and L-PRP were performed in 4 groups. To evaluate bone formation and remodeling of the defects, X-ray photography was taken at 2, 4, and 8 weeks postoperatively. The modified Lane-Sandhu scoring system was used to evaluate the bone formation. Two rabbits were sacrificed at 2, 4, 8 weeks after operation to harvest the specimens for histological observation, new blood vessel count and new bone area ratio. ResultsThe observations of radiology and histology displayed different degrees of bone regeneration at bone defect sites in each group. At 2, 4, and 8 weeks postoperatively, the results of Lane-Sandhu X-ray photography scoring, new blood vessel count, and new bone area ratio showed that groups C and D were significantly better than groups A and B, group D was significantly better than group C. and group B was significantly better than group A (P<0.05). ConclusionThese findings demonstrate that L-PRP can promote osteogenic differentiation of BMSCs in treating ANFH in rabbits, and core decompression associated with BMSCs and L-PRP is an effective and feasible method to treat ANFH.
ObjectiveTo explore the effect of fetal bovine serum (FBS) of different concentrations in the culture medium on osteogenic growth peptide (OGP) promoting bone marrow mesenchymal stem cells (BMSCs) proliferation and differentiation. MethodsBMSCs were separated from limb bones of 8 Sprague Dawley rats (5 weeks old) and purified by adherence method, and BMSCs at passage 3 were divided into 4 groups according to OGP concentration: OGP 1×10-10 mol/L group, OGP 1×10-9mol/L group, OGP 1×10-8 mol/L group, and control group without OGP; and 0, 2%, 5%, 8%, and 10%FBS concentration gradient was used in each group. The cell proliferation rate was detected by MTT method at 1, 3, 5, 7, 9, and 12 days after culture, and the activity of intracellular alkaline phosphatase (ALP) was determined by the method of p-nitrophenyl phosphate disodium at 9 days after culture. ResultsBMSCs showed adherent growth, rapid proliferation, long fiber vortex, and typical morphology. MTT analysis showed that cells could not sustain proliferation when FBS concentration was less than 5% in each group; when FBS concentration was above 8%, cells proliferated continually. Proliferation promoting effect of OGP 1×10-8 mol/L and 1×10-9 mol/L groups was significantly higher than that of the control group in all serum concentrations (P<0.05); when FBS concentration was lower than 10%, the proliferation promoting effect of OGP 1×10-8 mol/L group was significantly higher than that of the other 2 OGP groups (P<0.05), but when FBS concentration was 10%, OGP 1×10-8 mol/L group had no advantage of promoting proliferation. ALP test results showed that as the FBS concentration increased, ALP activity of all groups also significantly increased (P<0.05). Under the condition of 5%FBS and 8%FBS, the ALP activity of each OGP group was significantly greater than that of the control group, and it was the highest in OGP 1×10-8 mol/L group (P<0.05). Under the condition of 10%FBS, the ALP activity of each OGP group was still greater than that of the control group (P<0.05), but no significant difference was found between the OGP 1×10-8 mol/L group and OGP 1×10-9 mol/L group (P>0.05). ConclusionThe concentration of 8%FBS is the best concentration of serum for OGP promoting the proliferation and differentiation of BMSCs, and the most suitable concentration of promoting the proliferation and differentiation of BMSCs is OGP 1×10-8 mol/L.
ObjectiveTo comprehensively analyze the recent advancements in the field of mesenchymal stem cells (MSCs) derived exosomes (MSCs-exosomes) in tissue repair. MethodsThe literature about MSCs-exosomes in tissue repair was reviewed and analyzed. ResultsExosomes are biologically active microvesicles released from MSCs which are loaded with functional proteins, RNA, and microRNA. Exosomes can inhibit apoptosis, stimulate proliferation, alter cell phenotype in tissue repair of several diseases through cell-to-cell communication. ConclusionMSCs-exosomes is a novel source for the treatment of tissue repair. Further research of MSCs-exosomes biofunction, paracellular transport, and treatment mechanism will help the transform to clinical application.
Objective To systematically review the effectiveness and safety of autologous implantation of stem cells for diabetic peripheral neuropathy (DPN). Methods Randomized controlled trials on relevant studies were retrieved in databases including CBM (1978-2011.6), CNKI (1979-2011.6), MEDLINE (1950-2011.6), PubMed (1950-2011.6), EMbase (1970-2011.6) and The Cochrane Library (Issue 3, 2011). References of the included studies were also retrieved. Two reviewers independently screened literature according to the inclusion and exclusion criteria, extracted data, and assess the methodological quality of the included studies. Then, meta-analysis was performed using RevMan 5.0 software.Results Four RCTs involving 68 patients (136 limbs) were included, most of which were low in methodological quality. The results of meta-analysis indicated that, autologous stem cell therapy improved or even eliminated DPN symptoms including pain, numbness, and cold sensation in the limbs, intermittent limping, and rest pain. Compared with the routine therapy, autologous stem cell therapy improved tibial sensory nerve conduction velocity (MD=5.75, 95%CI 3.86 to 7.64, Plt;0.000 01), tibial motor nerve conduction velocity (MD=4.04, 95%CI 0.90 to 7.18, P=0.001), sural sensory nerve conduction velocity (MD=7.47, 95%CI 4.00 to 10.94, Plt;0.000 1), and sural motor nerve conduction velocity (MD=3.38, 95%CI 0.07 to 7.58, P=0.05), with no adverse reaction reported. Conclusion Current evidence shows that, autologous stem cell therapy is effective in treating DPN. Due to the lack of high quality studies, more high quality RCTs are needed to verify the above conclusion.
Objective To assess the effectiveness and safety of high-dose chemotherapy assisted with autologous peripheral blood stem cell treatment (APBSCT+HDC) for small cell lung cancer (SCLC). Methods The databases such as MEDLINE (1970 to January 2011), EMBASE (1980 to January 2011), Science Direct (1980 to January 2011), The Cochrane Library (Issue 3, 2010), CNKI (from the date of establishment to December 2010), CBM (from the date of establishment to December 2010) and Wanfang database (from the date of establishment to December 2010) were searched for collecting randomized controlled trials (RCTs) on APBSCT+HDC for SCLC. According to the inclusive and exclusive criteria, the trials were screened, the data were extracted, the methodological quality was assessed, and then Meta-analysis was conducted by using RevMan 5.0 software. Results A total of 6 RCTs involving 737 patients with SCLC were included. The results of Meta-analyses were as follows: the APBSCT+HDC for SCLC was significantly superior to the conventional chemotherapy in the total effective rate (RR=1.14, 95%CI 1.07 to 1.21, Plt;0.000 1) and the overall survival rate (RR=3.74, 95%CI 2.13 to 6.58, Plt;0.000 01), and it was superior in reducing the incidence of III/IV grade red blood cell reduction (RR=1.97, 95%CI 1.15 to 3.38, P=0.01) and thrombopenia (RR=1.93, 95%CI 1.06 to 3.54, P=0.03) with significant differences; but there was no significant difference between the two groups in reducing the incidence of III/IV leukopenia. Conclusions Compared with the conventional chemotherapy, APBSCT+HDC treatment for SCLC can improve the overall effective rate and overall survival rate, but it can also increase the risks of severe hematologic toxic reaction. Because of the small scale and low quality of the included studies, this conclusion still needs to be confirmed by high-quality, large-scale and multi-centered RCTs.
Objective To explore repair role of allogeneic bone marrow mesenchymal stem cells （BM-MSCs） transplantation on treating hepatic ischemia reperfusion injury （HIRI） in rats. Methods Ten rats were executed to get BM-MSCs， then BM-MSCs were cultured in vitro and dyed by 4，6-diamidino-2-phenylindole （DAPI）. Models of 70% hepatic ischemia reperfusion injury were eatablished. Thirty two rats were randomly divided into sham operation group （Sham group）， ischemia reperfusion group （I/R group）， Vitamin C group （VC group）， and BM-MSCs group. Serum samples were analyzed for ALT and AST， and hepatic tissue were for superoxide dismutase （SOD） and malondialdehyde （MDA）. Liver sections were stain with hematoxylin and eosin （HE） for histological analysis， TUNEL staining was applied to detect hepatic apoptosis. Serum and tissues were both collected at 24 h after reperfusion. Results The isolated BM-MSCs maintained vigorous growth in vitro. Specific markers for MSCs antigens CD29 and CD44 were detected by flow cytometry， but antigens CD34 and CD45 were not be detected. Models of HIRI were stable， and BM-MSCs were detected around the periportal area by DAPI staining. Compared with I/R group， levels of ALT， AST， MDA， and AI in the VC group and BM-MSCs group decreased at 24 h after reperfusion （P＜0.05）， meanwhile SOD level increased （P＜0.05）. Compared with VC group， levels of ALT， AST， MDA， and AI in the BM-MSC group decreased at 24 h after reperfusion （P＜0.05）， meanwhile SOD level increased （P＜0.05）. Conclusion BM-MSCs could protect HIRI by alleviating oxidative stress and inhibiting cellular apoptosis.
Objective To review the role of mTOR signal pathway in chemo-resistance of gastric cancer. Methods Domestic and international publications related mTOR signal pathway in chemo-resistance of gastric cancer in recent years were collected and reviewed. Results mTOR was a central signaling molecule of mTOR signal pathway， which regulated key cellular processes such as cell growth， cell proliferation， cell metabolism， and angiogenesis. Signaling molecules of mTOR signal pathway were overexpressed in gastric cancer. Moreover， mTOR signal pathway might play an important role in chemo-resistance of gastric cancer， and tumor stem cells were involved in it too. Conclusion As mTOR signal pathway plays an important role in chemo-resistance of gastric cancer， the combination of mTOR inhibitors and chemotherapy drugs may overcome the chemo-resistance of gastric cancer.