High-Fat Diets-Induced Metabolic Alterations Alter the Differentiation Potential of Adipose Tissue-Derived Stem Cells

Background: Adipose tissue-derived stem cells (ASC) possess the ability to differentiate into adipocytes or endothelial cells to help in the adipogenesis, vasculogenesis and vascular repair. This study aims at determining the impact of high-fat diets (HFD)-induced type 2 diabetes (T2D) on the differentiation potential of ASC. Results: C57BL/6J male mice were fed a vegetal (VD) or an animal (AD) HFD. Isolation of ACS from mice showing different levels of metabolic alterations reveals that advanced T2D did not affect the number of cells per gram of tissue. Rather, a higher proportion of inflammatory CD36+ cells was identified in HFD fed mice. Despite a marked decreased expression of adipogenic genes (aP2, C/EBPα and PPARγ2), ASC from HFD groups had a higher adipogenic potential and a lower endothelial differentiation potential in vitro compared to control. ASC from the VD group had enhanced cyclin B1 expression and had more adipogenic potential compared to AD group. Conclusion: Our results demonstrate that the metabolic modifications, linked to the nature of fatty acids in diets, modulate the differentiation potential of ASC with increased adipogenesis to the detriment of the endothelial pathway. Results highlight the importance of evaluating the ASC differentiation behavior in a context of autologous cell-based therapy for the repair of vascular tissues in diabetic patients.

Adipose tissue-derived stem cells as a therapeutic tool for cardiovascular disease

Adipose tissue-deried stem cells( ADSCs) are adult stem cells that can be easily harvested from subcutaneous adipose tissue. Many studies have demonstrated that ADSCs differentiate into vascular endothelial cells(VECs), vascular smooth muscle cells(VSMCs), and cardiomyocytes in vitro and in vivo. However, ADSCs may fuse with tissue-resident cells and obtain the corresponding characteristics of those cells. If fusion occurs, ADSCs may express markers of VECs, VSMCs, and cardiomyocytes without direct differentiation into these cell types. ADSCs also produce a variety of paracrine factors such as vascular endothelial growth factor, hepatocyte growth factor, and insulin-like growth factor-1 that have proangiogenic and/or antiapoptotic activities. Thus, ADSCs have the potential to regenerate the cardiovascular system via direct differentiation into VECs, VSMCs, and cardiomyocytes, fusion with tissueresident cells, and the production of paracrine factors. Numerous animal studies have demonstrated the efficacy of ADSC implantation in the treatment of acute myocardial infarction(AMI), ischemic cardiomyopathy(ICM), dilated cardiomyopathy, hindlimb ischemia, and stroke. Clinical studies regarding the use of autologous ADSCs for treating patients with AMI and ICM have recently been initiated. ADSC implantation has been reported as safe and effective so far. Therefore, ADSCs appear to be useful for the treatment of cardiovascular disease. However, the tumorigenic potential of ADSCs requires careful evaluation before their safe clinical application.

Human adipose tissue-derived stem cells in breast reconstruction following surgery for cancer: A controversial issue

Breast cancer is the most common cancer in women. Patients, in particular young women, after surgical removal of the tumor have a poorer quality of life and psychological problems. Plastic surgery procedures for breast reconstruction, including autologous fat grafting, concur to reduce cosmetic and psychological problems. The maintenance of the transplanted fat is partially due to the presence of resident adipose derived-stem cells (ASCs). The latter can be isolated by digestion and centrifugation from the stromal vascular fraction (SVF) of subcutaneous adipose tissue. Intraoperatory SVF/ASC enrichment has been proposed to stabilize and optimalize autologous fat engraftment for breast reconstructive surgery after mastectomy, but the safety of these procedures is still uncertain. Although the literature offers contrasting opinions concerning the effects of ASCs on cancer growth according to the tumor type, at the present time ASC implementation for regenerative medicine therapies should be carefully considered in patients previously treated for breast cancer. At the present, reconstructive therapy utilizing ASC-enriched fat grafting should be postponed until there is no evidence of active disease.

Unlocking the versatile potential:Adipose-derived mesenchymal stem cells in ocular surface reconstruction and oculoplastics

This review comprehensively explores the versatile potential of mesenchymal stem cells(MSCs)with a specific focus on adipose-derived MSCs.Ophthalmic and oculoplastic surgery,encompassing diverse procedures for ocular and periocular enhancement,demands advanced solutions for tissue restoration,functional and aesthetic refinement,and aging.Investigating immunomodulatory,regenerative,and healing capacities of MSCs,this review underscores the potential use of adipose-derived MSCs as a cost-effective alternative from bench to bedside,addressing common unmet needs in the field of reconstructive and regenerative surgery.

Over-expression of VEGF165 in the adipose tissue-derived stem cells via the lentiviral vector

Background Many researchers studied the possibility of using stem cells as gene therapeutic vector. But few related reports on the adipose tissue-derived stem cells （ADSCs） are available. Therefore we intended to construct a lentiviral VEGF165 expression vector and then infect the ADSCs to produce therapeutic seed cells.Methods EHS1001-68950485313912 clone was mutated by PCR method to produce consensus fragment of VEGF165 transcript （NM_001025368）. Lentivirus was enveloped with pGC-FU, pHelper 1.0 and pHelper 2.0 plasmids in 293T cells.And then the ADSCs （multiplicity of infection=20） were transfected with the vectors after titer determination. Stable expression of VEGF165 in ADSCs was confirmed by immunofluorescence staining, enzyme-linked immunosorbent assay （ELISA） and Western blotting analysis.Results DNA sequencing and 293T transfection verified VEGF165 was linked to the GFP fused vector. The virus titer is up to 2x10a determined by quantitative PCR. VEGF165 transduced cells could show green fluorescence confirmed by immunofluorescence staining （almost 95%）. ELISA analyses could detect out the density of VEGF was 850.86-1202.13pg/ml （mean （923.00±31.22） pg/ml） in the supernatant of VEGF16s-transduced cells but not detected in the GFP-transduced cells （P 〈0.001） and the Western blotting analyses also confirmed VEGF165 expression in VEGF165-transduced cells.Conclusions The VEGF165 over-expression ADSCs were obtained and may be used as a cell therapeutic tool and may be applied for vascular regeneration, especially in the treatment of erectile dysfunction.

Rho-associated coiled kinase inhibitor Y-27632 promotes neuronal-like differentiation of adult human adipose tissue-derived stem cells

Background Y-27632 is a specific inhibitor of Rho-associated coiled kinase （ROCK） and has been shown to promote the survival and induce the differentiation of a variety of cells types. However, the effects of Y-27632 on adult human adipose tissue-derived stem cells （ADSCs） are unclear. This study aimed to investigate the effects of Y-27632 on the neuronal-like differentiation of ADSCs. Methods ADSCs were isolated from women undergoing plastic surgery and cultured. ADSCs were treated with different doses of Y-27632 and observed morphological changes under microscope. The expression of nestin, neuron specific enolase （NSE） and microtubule-associated protein-2 （MAP-2） in ADSCs treated with Y-27632 was detected by immunocytochemistry and Western blotting analysis. Results Y-27632 had the potency to induce neuronal-like differentiation in ADSCs in a dose-dependent manner. Moreover, the differentiation induced by Y-27632 was recovered upon drug withdraw. ADSCs treated with Y-27632 expressed neuronal markers such as NSE, MAP-2 and nestin while untreated ADSCs did not express these markers. Conclusion Selective ROCK inhibitor Y-27632 could potentiate the neuronal-like differentiation of ADSCs, suggesting that Y-27632 could be utilized to induce the differentiation of ADSCs to neurons and facilitate the clinical application of ADSCs in tissue engineering.

Chemically induced hypoxia by dimethyloxalylglycine(DMOG)-loaded nanoporous silica nanoparticles supports endothelial tube formation by sustained VEGF release from adipose tissue-derived stem cells

Inadequate vascularization leading to insufficient oxygen and nutrient supply in deeper layers of bioartificial tissues remains a limitation in current tissue engineering approaches to which prevascularization offers a promising solution.Hypoxia triggering pre-vascularization by enhanced vascular endothelial growth factor(VEGF)expression can be induced chemically by dimethyloxalylglycine(DMOG).Nanoporous silica nanoparticles(NPSNPs,or mesoporous silica nanoparticles,MSNs)enable sustained delivery of molecules and potentially release DMOG allowing a durable capillarization of a construct.Here we evaluated the effects of soluble DMOG and DMOG-loaded NPSNPs on VEGF secretion of adipose tissue-derived stem cells(ASC)and on tube formation by human umbilical vein endothelial cells(HUVEC)-ASC co-cultures.Repeated doses of 100 mM and 500 mM soluble DMOG on ASC resulted in 3-to 7-fold increased VEGF levels on day 9(P<0.0001).Same doses of DMOG-NPSNPs enhanced VEGF secretion 7.7-fold(P<0.0001)which could be maintained until day 12 with 500 mM DMOG-NPSNPs.In fibrin-based tube formation assays,100 mM DMOG-NPSNPs had inhibitory effects whereas 50 mM significantly increased tube length,area and number of junctions transiently for 4 days.Thus,DMOG-NPSNPs supported endothelial tube formation by upregulated VEGF secretion from ASC and thus display a promising tool for prevascularization of tissue-engineered constructs.Further studies will evaluate their effect in hydrogels under perfusion.

Translational products of adipose tissue-derived mesenchymal stem cells:Bench to bedside applications

With developments in the field of tissue engineering and regenerative medicine,the use of biological products for the treatment of various disorders has come into the limelight among researchers and clinicians.Among all the available biological tissues,research and exploration of adipose tissue have become more robust.Adipose tissue engineering aims to develop by-products and their substitutes for their regenerative and immunomodulatory potential.The use of biodegradable scaffolds along with adipose tissue products has a major role in cellular growth,proliferation,and differentiation.Adipose tissue,apart from being the powerhouse of energy storage,also functions as the largest endocrine organ,with the release of various adipokines.The progenitor cells among the heterogeneous population in the adipose tissue are of paramount importance as they determine the capacity of regeneration of these tissues.The results of adipose-derived stemcell assisted fat grafting to provide numerous growth factors and adipokines that improve vasculogenesis,fat graft integration,and survival within the recipient tissue and promote the regeneration of tissue are promising.Adipose tissue gives rise to various by-products upon processing.This article highlights the significance and the usage of various adipose tissue by-products,their individual characteristics,and their clinical applications.

Anti-osteoarthritis effect of a combination treatment with human adipose tissue-derived mesenchymal stem cells and thrombospondin 2 in rabbits

BACKGROUND Osteoarthritis(OA),a chronic age-related disease characterized by the slowly progressive destruction of articular cartilage,is one of the leading causes of disability.As a new strategy for treatment of OA,mesenchymal stem cells(MSCs)have the potential for articular cartilage regeneration.Meanwhile,thrombospondin 2(TSP2)promotes the chondrogenic differentiation of MSCs.AIM To investigate whether TSP2 induces chondrogenic differentiation of human adipose-derived MSCs(hADMSCs)and potentiates the therapeutic effects of hADMSCs in OA rabbits.METHODS We investigated the chondrogenic potential of TSP2 in hADMSCs by analyzing the expression of chondrogenic markers as well as NOTCH signaling genes in normal and TSP2 small interfering RNA(siRNA)-treated stem cells.Anterior cruciate ligament transection surgery was performed in male New Zealand white rabbits,and 8 wk later,hADMSCs(1.7×10^6 or 1.7×10^7 cells)were injected into the injured knees alone or in combination with intra-articular injection of TSP2(100 ng/knee)at 2-d intervals.OA progression was monitored by gross,radiological,and histological examinations.RESULTS In hADMSC culture,treatment with TSP2 increased the expression of chondrogenic markers(SOX9 and collagen Ⅱ)as well as NOTCH signaling genes(JAGGED1 and NOTCH3),which were inhibited by TSP2 siRNA treatment.In vivo,OA rabbits treated with hADMSCs or TSP2 alone exhibited lower degree of cartilage degeneration,osteophyte formation,and extracellular matrix loss 8 wk after cell transplantation.Notably,such cartilage damage was further alleviated by the combination of hADMSCs and TSP2.In addition,synovial inflammatory cytokines,especially tumor-necrosis factor-α,markedly decreased following the combination treatment.CONCLUSION The results indicate that TSP2 enhances chondrogenic differentiation of hADMSCs via JAGGED1/NOTCH3 signaling,and that combination therapy with hADMSCs and TSP2 exerts synergistic effects in the cartilage regeneration of OA joints.

Adipose mesenchymal stem cell-derived extracellular vesicles reduce glutamate-induced excitotoxicity in the retina

Adipose mesenchymal stem cells(ADSCs)have protective effects against glutamate-induced excitotoxicity,but ADSCs are limited in use for treatment of optic nerve injury.Studies have shown that the extracellular vesicles(EVs)secreted by ADSCs(ADSC-EVs)not only have the function of ADSCs,but also have unique advantages including non-immunogenicity,low probability of abnormal growth,and easy access to target cells.In the present study,we showed that intravitreal injection of ADSC-EVs substantially reduced glutamate-induced damage to retinal morphology and electroretinography.In addition,R28 cell pretreatment with ADSC-EVs before injury inhibited glutamate-induced overload of intracellular calcium,downregulation ofα-amino-3-hydroxy-5-methyl-4-isoxazoleproprionic acid receptor(AMPAR)subunit GluA2,and phosphorylation of GluA2 and protein kinase C alpha in vitro.A protein kinase C alpha agonist,12-O-tetradecanoylphorbol 13-acetate,inhibited the neuroprotective effects of ADSC-EVs on glutamate-induced R28 cells.These findings suggest that ADSCEVs ameliorate glutamate-induced excitotoxicity in the retina through inhibiting protein kinase C alpha activation.

Transplantation of neural progenitor cells differentiated from adipose tissue-derived stem cells for treatment of sciatic nerve injury

Objectives: Currently, the clinical repair of sciatic nerve injury remains difficult.Previous studies have confirmed that transplantation of adipose tissue-derived stem cells promotes nerve regeneration and restoration at peripheral nerve injury sites. Methods: In this study, adipose tissue-derived stem cells were induced to differentiate into neural progenitor cells, transfected with a green fluorescent protein-containing lentivirus, and then transplanted into the lesions of rats with sciatic nerve compression injury. Results: Fluorescence microscopy revealed that the transplanted cells survived,migrated, and differentiated in rats. At two weeks post-operation, a large number of transplanted cells had migrated to the injured lesions; at six weeks post-operation, transplanted cells were visible around the injured nerve and several cells were observed to express a Schwann cell marker. Sciatic function index and electrophysiological outcomes of the transplantation group were better than those of the control group. Cell transplantation promoted the recovery of motor nerve conduction velocity and compound muscle action potential amplitude, and reduced gastrocnemius muscle atrophy.Conclusions: Our experimental findings indicate that neural progenitor cells,differentiated from adipose tissue-derived stem cells, are potential seed stem cells that can be transplanted into lesions to treat sciatic nerve injury. This provides a theoretical basis for their use in clinical applications.

Ameliorative effects of human adipose tissue-derived mesenchymal stem cells on myelin basic protein-induced experimental autoimmune encephalomyelitis in Lewis rats

Mesenchymal stem cells have been previously shown to exert an immunomodulatory function. The present study sought to investigate the effects of multipotential human adipose tissue-derived mesenchymal stem cells （hAdMSCs） on disease progression and cytokine expression in Lewis rats with experimental autoimmune encephalomyelitis （EAE） induced by myelin basic protein. The duration of EAE paralysis in the group treated on day 7 posfimmunization with 5 × 10^6 hAdMSCs was significantly reduced compared with the vehicle-treated controls and the 1 x 106 hAdMSC- treated group. The duration of EAE paralysis in the groups treated with 5 × 10^6 hAdMSCs on both day 1 and day 7 postimmunization was significantly reduced compared with the vehicle-treated controls and the groups treated with 5 × 10^6 hAdMSCs on both day 7 and day 10 postimmunization. The mRNA expression of interleukin-10 and indoleamine 2, 3-dioxygenase was significantly decreased in the hAdMSC-treated group compared with the vehicle-treated group. These findings suggest that the ameliorative effects of hAdMSCs on EAE symptoms operate in a dose- and time-dependent manner and can be mediated in part by the ample production of anti-inflammatory cytokines.

Optimization of adipose tissue-derived mesenchymal stromal cells transplantation for bone marrow repopulation following irradiation

BACKGROUND Bone marrow(BM)suppression is one of the most common side effects of radiotherapy and the primary cause of death following exposure to irradiation.Despite concerted efforts,there is no definitive treatment method available.Recent studies have reported using mesenchymal stromal cells(MSCs),but their therapeutic effects are contested.AIM We administered and examined the effects of various amounts of adipose-derived MSCs(ADSCs)in mice with radiation-induced BM suppression.METHODS Mice were divided into three groups:Normal control group,irradiated(RT)group,and stem cell-treated group following whole-body irradiation(WBI).Mouse ADSCs(mADSCs)were transplanted into the peritoneal cavity either once or three times at 5×10^(5) cells/200μL.The white blood cell count and the levels of,plasma cytokines,BM mRNA,and BM surface markers were compared between the three groups.Human BM-derived CD34+hematopoietic progenitor cells were co-cultured with human ADSCs(hADSCs)or incubated in the presence of hADSCs conditioned media to investigate the effect on human cells in vitro.RESULTS The survival rate of mice that received one transplant of mADSCs was higher than that of mice that received three transplants.Multiple transplantations of ADSCs delayed the repopulation of BM hematopoietic stem cells.Anti-inflammatory effects and M2 polarization by intraperitoneal ADSCs might suppress erythropoiesis and induce myelopoiesis in sub-lethally RT mice.CONCLUSION The results suggested that an optimal amount of MSCs could improve survival rates post-WBI.

Clinical and Magnetic Resonance Image Changes of Platelet-Rich Plasma Therapy in Combination with Human Mesenchymal Stem Cells from Autologous Adipose Tissue for Knee Osteoarthritis Treatment

Objective: To evaluate the efficacy based on clinical symptom and on magnetic resonance image of platelet-rich plasma therapy in combination with mesenchymal stem cells from autologous adipose tissue for knee osteoarthritis treatment. Patients and Method: 30 patients including 26 females and 4 males;correspondingly, 60 knee joints were diagnosed with osteoarthritis with stages II - III of Kellgren and Lawrence, their mean age was 58.63 ± 11.11. All were injected with autologous platelet-rich plasma that was extracted by PRP set, APC 30 PRP PRCEDURE PRAK and autologously extracted mesenchymal stem cells from abdominal adipose tissue using the ADI-25-01 ADIPOSEPRCEDURE PRAK of USA. Results: After 12 months: the pain level according to VAS score at the right knee joint was decreased from 6.0 ± 1.28 before treatment to 1.9 ± 0.3;VAS score at the left knee joint was decreased from 6.43 ± 1.19 to 2.25 ± 0.43. Total Lequene score at right knee joint was decreased from 16.04 ± 1.57 before treatment to 4.31 ± 1.04, at left knee joint was decreased from 17.52 ± 1.74 before treatment to 5.15 ± 1.48. Total WOMAC score at right knee joint was decreased from 55.93 ± 5.56 to 10.37 ± 1.56;at left knee joint was decreased from 53.97 ± 5.57 to 10.07 ± 1.59. There were 86.77% joints with cartilage thickness change and the patellar cartilage thickness was increased from 1.56 ± 0.09 mm before treatment to 1.65 ± 0.09 mm. Conclusion: The treatment of knee osteoarthritis by platelet-rich plasma therapyin combination with mesenchymal stem cells from autologous adipose tissue is effective in reducing pain, improving patient's mobility and walking function, reforming articular cartilage thickness on magnetic resonance image.

Outcomes of combined mitochondria and mesenchymal stem cellsderived exosome therapy in rat acute respiratory distress syndrome and sepsis

BACKGROUND The treatment of acute respiratory distress syndrome(ARDS)complicated by sepsis syndrome(SS)remains challenging.AIM To investigate whether combined adipose-derived mesenchymal-stem-cells(ADMSCs)-derived exosome(EXAD)and exogenous mitochondria(mitoEx)protect the lung from ARDS complicated by SS.METHODS In vitro study,including L2 cells treated with lipopolysaccharide(LPS)and in vivo study including male-adult-SD rats categorized into groups 1(sham-operated-control),2(ARDS-SS),3(ARDS-SS+EXAD),4(ARDS-SS+mitoEx),and 5(ARDS-SS+EXAD+mitoEx),were included in the present study.RESULTS In vitro study showed an abundance of mitoEx found in recipient-L2 cells,resulting in significantly higher mitochondrial-cytochrome-C,adenosine triphosphate and relative mitochondrial DNA levels(P<0.001).The protein levels of inflammation[interleukin(IL)-1β/tumor necrosis factor(TNF)-α/nuclear factor-κB/toll-like receptor(TLR)-4/matrix-metalloproteinase(MMP)-9/oxidative-stress(NOX-1/NOX-2)/apoptosis(cleaved-caspase3/cleaved-poly(ADP-ribose)polymerase)]were significantly attenuated in lipopolysaccharide(LPS)-treated L2 cells with EXAD treatment than without EXAD treatment,whereas the protein expressions of cellular junctions[occluding/β-catenin/zonula occludens(ZO)-1/E-cadherin]exhibited an opposite pattern of inflam-mation(all P<0.001).Animals were euthanized by 72 h post-48 h-ARDS induction,and lung tissues were harvested.By 72 h,flow cytometric analysis of bronchoalveolar lavage fluid demonstrated that the levels of inflam-matory cells(Ly6G+/CD14+/CD68+/CD11b/c+/myeloperoxidase+)and albumin were lowest in group 1,highest in group 2,and significantly higher in groups 3 and 4 than in group 5(all P<0.0001),whereas arterial oxygen-saturation(SaO2%)displayed an opposite pattern of albumin among the groups.Histopathological findings of lung injury/fibrosis area and inflammatory/DNA-damaged markers(CD68+/γ-H2AX)displayed an identical pattern of SaO2%among the groups(all P<0.0001).The protein expressions of inflammatory(TLR-4/MMP-9/IL-1β/TNF-α)/oxidative stress(NOX-1/NOX-2/p22phox/oxidized protein)/mitochondrial-damaged(cytosolic-cytochrome-C/dynamin-related protein 1)/autophagic(beclin-1/Atg-5/ratio of LC3B-II/LC3B-I)biomarkers exhibited a similar manner,whereas antioxidants[nuclear respiratory factor(Nrf)-1/Nrf-2]/cellular junctions(ZO-1/E-cadherin)/mitochondrial electron transport chain(complex I-V)exhibited an opposite manner of albumin among the groups(all P<0.0001).CONCLUSION Combined EXAD-mitoEx therapy was better than merely one for protecting the lung against ARDS-SS induced injury.

Therapeutic and regenerative potential of different sources of mesenchymal stem cells for cardiovascular diseases

Mesenchymalstemcells(MSCs)areidealcandidatesfortreatingmanycardiovasculardiseases.MSCscanmodify the internal cardiac microenvironment to facilitate their immunomodulatory and differentiation abilities,which are essential to restore heart function.MSCs can be easily isolated from different sources,including bone marrow,adipose tissues,umbilical cord,and dental pulp.MSCs from various sources differ in their regenerative and therapeutic abilities for cardiovascular disorders.In this review,we will summarize the therapeutic potential of each MSC source for heart diseases and highlight the possible molecular mechanisms of each source to restore cardiac function.

High glucose microenvironment and human mesenchymal stem cell behavior

High glucose(HG)culture conditions in vitro and persistent exposure to hyperglycemia in diabetes patients are detrimental to stem cells,analogous to any other cell type in our body.It interferes with diverse signaling pathways,i.e.mammalian target of rapamycin(mTOR)-phosphoinositide 3-kinase(PI3K)-Akt signaling,to impact physiological cellular functions,leading to low cell survival and higher cell apoptosis rates.While elucidating the underlying mechanism responsible for the apoptosis of adipose tissue-derived mesenchymal stem cells(MSCs),a recent study has shown that HG culture conditions dysregulate mTORPI3K-Akt signaling in addition to mitochondrial malfunctioning due to defective mitochondrial membrane potential(MtMP)that lowers ATP production.This organelle-level dysfunction energy-starves the cells and increases oxidative stress and ultrastructural abnormalities.Disruption of the mitochondrial electron transport chain produces an altered mitochondrial NAD+/NADH redox state as evidenced by a low NAD+/NADH ratio that primarily contributes to the reduced cell survival in HG.Some previous studies have also reported altered mitochondrial membrane polarity(causing hyperpolarization)and reduced mitochondrial cell mass,leading to perturbed mitochondrial homeostasis.The hostile microenvironment created by HG exposure creates structural and functional changes in the mitochondria,altering their bioenergetics and reducing their capacity to produce ATP.These are significant data,as MSCs are extensively studied for tissue regeneration and restoring their normal functioning in cell-based therapy.Therefore,MSCs from hyperglycemic donors should be cautiously used in clinical settings for cell-based therapy due to concerns of their poor sur-vival rates and increased rates of post engraftment proliferation.As hypergly-cemia alters the bioenergetics of donor MSCs,rectifying the loss of MtMP may be an excellent target for future research to restore the normal functioning of MSCs in hyperglycemic patients.

Comparative effectiveness of adipose-derived mesenchymal stromal cells in the management of knee osteoarthritis:A meta-analysis

BACKGROUND Osteoarthritis(OA)is the most common joint disorder,is associated with an increasing socioeconomic impact owing to the ageing population.AIM To analyze and compare the efficacy and safety of bone-marrow-derived mesenchymal stromal cells(BM-MSCs)and adipose tissue-derived MSCs(AD-MSCs)in knee OA management from published randomized controlled trials(RCTs).METHODS Independent and duplicate electronic database searches were performed,including PubMed,EMBASE,Web of Science,and Cochrane Library,until August 2021 for RCTs that analyzed the efficacy and safety of AD-MSCs and BM-MSCs in the management of knee OA.The visual analog scale(VAS)score for pain,Western Ontario McMaster Universities Osteoarthritis Index(WOMAC),Lysholm score,Tegner score,magnetic resonance observation of cartilage repair tissue score,knee osteoarthritis outcome score(KOOS),and adverse events were analyzed.Analysis was performed on the R-platform using OpenMeta(Analyst)software.Twenty-one studies,involving 936 patients,were included.Only one study compared the two MSC sources without patient randomization;hence,the results of all included studies from both sources were pooled,and a comparative critical analysis was performed.RESULTS At six months,both AD-MSCs and BM-MSCs showed significant VAS improvement(P=0.015,P=0.012);this was inconsistent at 1 year for BM-MSCs(P<0.001,P=0.539),and AD-MSCs outperformed BM-MSCs compared to controls in measures such as WOMAC(P<0.001,P=0.541),Lysholm scores(P=0.006;P=0.933),and KOOS(P=0.002;P=0.012).BM-MSC-related procedures caused significant adverse events(P=0.003)compared to AD-MSCs(P=0.673).CONCLUSION Adipose tissue is superior to bone marrow because of its safety and consistent efficacy in improving pain and functional outcomes.Future trials are urgently warranted to validate our findings and reach a consensus on the ideal source of MSCs for managing knee OA.

Immunomodulatory effects of mesenchymal stem cells derived from adipose tissues in a rat orthotopic liver transplantation model

BACKGROUND: Acute rejection after liver transplantation is usually treated with large doses of immunosuppressants with severe toxic and side-effects, so it is imperative to find a safe and effective method for preventing and treating rejection. This study was designed to confirm the immunomodulatory effects of rat mesenchymal stem cells (MSCs) in vitro and investigate the tolerogenic features in a rat model of allogeneic liver transplantation. METHODS: MSCs were isolated from adipose tissue of Sprague-Dawley (SD) rats and cultured. In vitro, MSCs were added into a mixed lymphocyte culture (MLC) system to study the inhibitory effects of MSCs on the proliferation of T lymphocytes in Wistar rats. By using SD and Wistar rats as liver donors and recipients, an orthotopic liver transplantation model was established and the rats were divided into a MSC-treated group and a blank control group. On postoperative day 7, all rats were sacrificed, and the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), interleukin-2 (IL-2) and interleukin-10 (IL-10) were measured. The pathological changes of liver tissue and apoptosis of hepatocytes were also assessed. RESULTS: In in vitro MLC, T lymphocyte proliferation in Wistar rats was significantly inhibited by 48.44%. In the MSC-treated group, the levels of ALT, AST, TBIL, IL-2 and IL-10 were 134.2 +/- 45.0 U/L, 162.5 +/- 30.5 U/L, 30.6 +/- 5.4 mu mol/L, 187.35 +/- 18.26 mu g/L and 193.95 +/- 37.62 mu g/L, and those in the blank control group were 355.6 +/- 54.3 U/L, 296.4 +/- 71.2 U/L, 145.7 +/- 28.6 +/- mol/L, 295.73 +/- 57.15 mu g/L and 75.12 +/- 11.23 mu g/L, respectively, with statistically significant differences (P<0.05). Pathological examination revealed that the rejection in the MSC-treated group was clearly alleviated compared with that in the blank control group. TUNEL indicated that the apoptosis of hepatocytes in the MSC-treated group was milder than that in the blank control group (P<0.05). CONCLUSION: Adipose-derived MSCs clearly inhibit recipient-derived T lymphocyte proliferation in MLC and significantly alleviate acute rejection following orthotopic liver transplantation in rats.

Hepatogenic differentiation of human mesenchymal stem cells from adipose tissue in comparison with bone marrow mesenchymal stem cells

AIM： To investigate and compare the hepatogenic transdifferentiation of adipose tissue-derived stem cells （ADSC） and bone marrow-derived mesenchymal stem cells （BMSC） in vitro. Transdifferentiation of BMSC into hepatic cells in vivo has been described. Adipose tissue represents an accessible source of ADSC, with similar characteristics to BMSC. METHODS： BMSCs were obtained from patients undergoing total hip arthroplasty and ADSC from human adipose tissue obtained from lipectomy. Cells were grown in medium containing 15% human serum. Cultures were serum deprived for 2 d before cultivating under similar pro-hepatogenic conditions to those of liver development using a 2-step protocol with sequential addition of growth factors, cytokines and hormones. Hepatic differentiation was RT-PCR-assessed and liver-marker genes were immunohistochemically analysed.RESULTS： BMSC and ADSC exhibited a fibroblastic morphology that changed to a polygonal shape when cells differentiated. Expression of stem cell marker Thyl decreased in differentiated ADSC and BMSC. However, the expression of the hepatic markers, albumin and CYPs increased to a similar extent in differentiated BMSC and ADSC. Hepatic gene activation could be attributed to increased liver-enriched transcription factors （C/EBPβ and HNF4α）, as demonstrated by adenoviral expression vectors.CONCLUSION： Mesenchymal stem cells can be induced to hepatogenic transdifferentiation in vitro. ADSCs have a similar hepatogenic differentiation potential to BMSC, but a longer culture period and higher proliferation capacity. Therefore, adipose tissue may be an ideal source of large amounts of autologous stem cells, and may become an alternative for hepatocyte regeneration, liver cell transplantation or preclinical drug testing.