Bone marrow-derived mesenchymal stem cell-derived exosomeloaded miR-129-5p targets high-mobility group box 1 attenuates neurological-impairment after diabetic cerebral hemorrhage

BACKGROUND Diabetic intracerebral hemorrhage(ICH)is a serious complication of diabetes.The role and mechanism of bone marrow mesenchymal stem cell(BMSC)-derived exosomes(BMSC-exo)in neuroinflammation post-ICH in patients with diabetes are unknown.In this study,we investigated the regulation of BMSC-exo on hyperglycemia-induced neuroinflammation.AIM To study the mechanism of BMSC-exo on nerve function damage after diabetes complicated with cerebral hemorrhage.METHODS BMSC-exo were isolated from mouse BMSC media.This was followed by transfection with microRNA-129-5p(miR-129-5p).BMSC-exo or miR-129-5poverexpressing BMSC-exo were intravitreally injected into a diabetes mouse model with ICH for in vivo analyses and were cocultured with high glucoseaffected BV2 cells for in vitro analyses.The dual luciferase test and RNA immunoprecipitation test verified the targeted binding relationship between miR-129-5p and high-mobility group box 1(HMGB1).Quantitative polymerase chain reaction,western blotting,and enzyme-linked immunosorbent assay were conducted to assess the levels of some inflammation factors,such as HMGB1,interleukin 6,interleukin 1β,toll-like receptor 4,and tumor necrosis factorα.Brain water content,neural function deficit score,and Evans blue were used to measure the neural function of mice.RESULTS Our findings indicated that BMSC-exo can promote neuroinflammation and functional recovery.MicroRNA chip analysis of BMSC-exo identified miR-129-5p as the specific microRNA with a protective role in neuroinflammation.Overexpression of miR-129-5p in BMSC-exo reduced the inflammatory response and neurological impairment in comorbid diabetes and ICH cases.Furthermore,we found that miR-129-5p had a targeted binding relationship with HMGB1 mRNA.CONCLUSION We demonstrated that BMSC-exo can reduce the inflammatory response after ICH with diabetes,thereby improving the neurological function of the brain.

Autologous bone marrow derived stem cell therapy in patients with type 2 diabetes mellitus-defining adequate administration methods

AIM To carry out randomized trial for evaluating effects of autologous bone marrow derived stem cell therapy(ABMSCT) through different routes.METHODS Bone marrow aspirate was taken from the iliac crest of patients. Bone marrow mononuclear cells were separatedand purified using centrifugation. These cells were then infused in a total of 21 patients comprising three groups of 7 patients each. Cells were infused into the superior pancreaticoduodenal artery(Group Ⅰ), splenic artery(Group Ⅱ) and through the peripheral intravenous route(Group Ⅲ). Another group of 7 patients acted as controls and a sham procedure was carried out on them(Group Ⅳ). The cells were labelled with the PET tracer F18-FDG to see their homing and in vivo distribution. Data for clinical outcome was expressed as mean ± SE. All other data was expressed as mean ± SD. Baseline and post treatment data was compared at the end of six months, using paired t-test. Cases and controls data were analyzed using independent t-test. A probability(P) value of < 0.05 was regarded as statistically significant. Measures of clinical outcome were taken as the change or improvement in the following parameters:(1) C-peptide assay;(2) HOMA-IR and HOMA-B;(3) reduction in Insulin dose; subjects who showed reduction of insulin requirement of more than 50% from baseline requirement were regarded as responders; and(4) reduction in HbA 1c. RESULTS All the patients, after being advised for healthy lifestyle changes, were evaluated at periodical intervals and at the end of 6 mo. The changes in body weight, body mass index, waist circumference and percentage of body fat in all groups were not significantly different at the end of this period. The results of intra-group comparison before and after ABMSCT at the end of six months duration was as follows:(1) the area under C-peptide response curve was increased at the end of 6 mo however the difference remained statistically non-significant(P values for fasting C-peptide were 0.973, 0.103, 0.263 and 0.287 respectively and the P values for stimulated C-peptide were 0.989, 0.395, 0.325 and 0.408 respectively for groups Ⅰ?to Ⅳ);(2) the Insulin sensitivity indices of HOMA IR and HOMA B also did not show any significant differences(P values for HOMA IR were 0.368, 0.223, 0.918 and 0.895 respectively and P values for HOMA B were 0.183, 0.664, 0.206 and 0.618 respectively for groups Ⅰto Ⅳ);(3) Group Ⅰshowed a significant reduction in Insulin dose requirement(P < 0.01). Group Ⅱ patients also achieved a significant reduction in Insulin dosages(P = 0.01). The Group Ⅰand Group Ⅱ patients together constituted the targeted group wherein the feeding arteries to pancreas were used for infusing stem cells. Group Ⅲ, which was the intravenous group, showed a non-significant reduction in Insulin dose requirement(P = 0.137). Group Ⅳ patients which comprised the control arm also showed a significant reduction in Insulin dosages at the end of six months(P < 0.05); and(4) there was a non-significant change in the Hb A1 c levels at the end of 6 mo across all groups(P = 0.355, P = 0.351, P = 0.999 and P = 0.408 respectively for groups Ⅰto Ⅳ). CONCLUSION Targeted route showed a significant reduction in Insulin requirement at the end of six months of study period whereas the intravenous group failed to show reduction.

α1-antitrypsin combined with bone marrow mesenchymal stem cells regulates retinopathy in diabetic rats via p38 MAPK/NF-κB signaling pathway

Objective:To investigate the effect ofα1-antitrypsin combined with bone marrow mesenchymal stem cells on retinopathy in diabetic rats and its mechanism.Methods:A model of diabetic retinopathy was established by intraperitoneal injection of streptozotocin.The 30 Wistar rats successfully modeled were randomly divided into a model group,a bone marrow mesenchymal stem cell group and a combined group(α1-antitrypsin combined with bone marrow Mesenchymal stem cells),the blood glucose and serum insulin levels of diabetic rats were measured 4 weeks after treatment.Enzyme-linked immunosorbent assay(ELISA)for measuring serum inflammatory factors IL-1β,IL-6 and TNF-α in rats.Observing the pathological morphology of rat retina under hematoxylin-eosin staining(HE).TUNEL staining to observe the apoptosis of rat retinal nerve cells.Immunohistochemical method to detect the expression level of CD45 in retinal tissue.Real-time fluorescence quantitative PCR was used to detect the expression of retinal vascular endothelial growth factor(VEGF),hypoxiainducible factor-1α(HIF-1α),and angiotensinⅡ(ANGⅡ)mRNA.Western blot was used to detect the expression of p38 MAPK/NF-κB signaling pathway-related proteins in the retinal tissue of each group of rats.Results:Compared with the control group,the rats in the model group had increased blood glucose,decreased insulin levels,increased serum IL-1β,IL-6,and TNF-α levels,and had obvious lesions in the retina.CD45 showed high expression in retinal tissue,VEGF,HIF-1α,ANGⅡ mRNA expression increased,p-p38,p-p65,p-IκBα protein expression increased(P<0.05).Compared with the model group,the bone marrow mesenchymal stem cell group and the combined group have decreased blood glucose,increased insulin levels,and decreased serum IL-1β,IL-6 and TNF-α levels.Retinopathy is improved,apoptosis of retinal nerve cells is reduced,CD45 expression in retinal tissue is reduced,VEGF,HIF-1α,ANGⅡ mRNA expression is decreased,and p-p38,p-p65,p-IκBα protein expression is decreased.Compared with the bone marrow mesenchymal stem cell group,the effect of the combined group was more obvious(P<0.05).Conclusion:α1-antitrypsin combined with bone marrow mesenchymal stem cell transplantation can improve the degree of retinopathy in diabetic rats.The mechanism may be related to the inhibition of p38 MAPK/NF-κB signaling pathway.

Utility of co-transplanting mesenchymal stem cells in islet transplantation

Islet transplantation is characterized by the transplantation of isolated islets from donor pancreata into a diabetic recipient. Although it is a viable choice in the treatment of insulin dependent diabetes mellitus, most patients (approximately 90%) require insulin five years after transplantation. Recently, the co-transplantation of mesenchymal stem cells (MSCs) and islets in animal studies has revealed the effectiveness of MSCs co-transplantation for improving islet function. Themechanisms underlying the beneficial impact of MSCs include immunomodulation and the promotion of angiogenesis. In this review, we discuss MSCs and how they support improved graft survival and function.

C-peptide increase in chronic type 1 diabetic patients treated with autologous bone marrow cell transplantation through pancreatic artery catheterization: Three years follow-up

Background: Recent extensive clinical evidence demonstrated that autologous adult stem cell therapy was safe and effective as a treatment strategy for type 1 diabetes. Our initial work was designed to examine the safety and efficacy of the implantation technique on 20 subjects with six months of evolution. This new report analyzes the results from three years follow up. Methods: With the authorization from the Ministry of Health of Argentina, 20 subjects with type 1 diabetes were treated with single autologous bone marrow cell transplantation into pancreatic blood flow through pancreatic artery catheterization immediately after bone marrow aspiration. The primary endpoint was defined as normalization of C-peptide and glycated hemoglobin (HbA1c) with insulin independence at 3 years posttreatment. Results: 15 subjects (75%) achieved clinical improvements. 7 subjects (33%) reached the primary endpoint, in which 4 subjets with decreased C-peptide levels required insulin administration again at 3 years post-treatment. Other 8 subjects (34%) showed partial function at 3 years post-treatment. There were no serious adverse events observed. No increases of islet cell antibody (ICA) and glutamic acid decarboxylase (GAD) antibody. Conclusion: This procedure may be a safe and effective treatment for chronic type 1 diabetes. The follow-up results showed a significant increase of the pancreatic secretion of C-peptide and a decrease in the daily dose of exogenous insulin. This effect partially disappears by the three years follow-up without an increase of the level of the ICA and GAD antibodies.

Tetrahedral framework nucleic acids promote the proliferation and differentiation potential of diabetic bone marrow mesenchymal stem cell

Diabetes mellitus considerably affects bone marrow mesenchymal stem cells(BMSCs),for example,by inhibiting their proliferation and differentiation potential,which enhances the difficulty in endogenous bone regeneration.Hence,effective strategies for enhancing the functions of BMSCs in diabetes have farreaching consequences for bone healing and regeneration in diabetes patients.Tetrahedral framework nucleic acids(tFNAs)are nucleic acid nanomaterials that can autonomously enter cells and regulate their behaviors.In this study,we evaluated the effects of tFNAs on BMSCs from diabetic rats.We found that tFNAs could promote the proliferation,migration,and osteogenic differentiation of BMSCs from rats with type 2 diabetes mellitus,and inhibited cell senescence and apoptosis.Furthermore,tFNAs effectively scavenged the accumulated reactive oxygen species and activated the suppressed protein kinase B(Akt)signaling pathway.Overall,we show that tFNAs can recover the proliferation and osteogenic potential of diabetic BMSCs by alleviating oxidative stress and activating Akt signaling.The study provides a strategy for endogenous bone regeneration in diabetes and also paves the way for exploiting DNA-based nanomaterials in regenerative medicine.

Autologous bone marrow stem cell transplantation for the treatment of type 2 diabetes mellitus

Background Autologous peripheral stem cell transplantation was first reported in 2007 to treat type 1 diabetes mellitus （DM） and achieved encouraging effect, but whether similar outcome can be achieved in type 2 DM is not well demonstrated. The objective of this study was to determine the effect of combination of autologous bone marrow stem cell transplantation （BMT） and hyperbaric oxygen treatment on type 2 DM. Methods The study involved 31 patients with type 2 DM （aged 33 to 62 years） from January 2009 to January 2011 in the Central Hospital of Wuhan, China. Clinical variables （body mass index, duration of DM, insulin requirement, oral hypoglycemic drugs, time free from insulin, time free from oral drugs） and laboratory variables （hemoglobin Alc （HbAlc）） mononuclear cells infused, and C-peptide in four time points） were assessed. Purified bone marrow stem cells were infused into major pancreatic arteries. Follow-up was performed at the 30, 90, 180, 360, 540 and 720 days （mean 321 days） after BMT. Results Mean HbAlc values showed a significant reduction during follow-up in all patients after BMT. It decreased by more than 1.5% （from 8.7% to 7.1%） as quickly as at 30 days after BMT. Afterwards mean HbAlc fluctuated between plus or minus 0.5% until 24 months rather than declined continuously. At 90 days after the combined therapy C-peptide increased significahtly compared with baseline （P 〈0.0001）. But in other time points C-peptide was similar with baseline data （P〉0.3）. All patients had insulin and/or oral hypoglycemic drugs reduced to different levels. The dose of insulin of 7 patients （7/26, 27%） reduced for a period of time after BMT. Conclusions Combined therapy of intrapancreatic BMT and hyperbaric oxygen treatment can improve glucose control and reduce the dose of insulin and/or oral hypoglycemic drugs in type 2 DM patients, but it only improve pancreatic 13-cell function transiently. Further randomized controlled clinical trials involved more patients will be required to confirm these findings and the mechanism needs to be illustrated deeply.

Expression of Pdx-1 in bone marrow mesenchymal stem cells promotes differentiation of islet-like cells in vitro

Bone marrow mesenchymal stem cells (BMSCs) have the ability of self-renewaland multi-directional differentiation. Recent reports showed that BMSCs could differentiate intoendocrine cells of pancreas. However, the differentiation is not efficient enough to produceinsulin-producing cells for the future therapeutic use. Pdx-1 is a crucial regulator for pancreaticdevelopment. Therefore we constructed a eukaryotic expression vector containing Pdx-1 to determinethe effect of Pdx-1 expression on differentiation of BMSCs in vitro. The results showed that BMSCscould self-assemble to form functional pancreatic islet-like structures after differentiation invitro. The proportion of insulin-producing cells differentiated from Pdx-1 +BMSCs was 28.23%+-2.56%,higher than that from BMSCs transfected with vacant vector and Pdx-1'' BMSCs (7.23%+-1.56% and4.08%+-2.69% respectively) by flow cytometry. Immunocytochemical examination also testified theexpression of multiple bate-cells-specific genes such as insulin, glucagons, somatostatin indifferentiated BMSCs. The results also revealed that the expressions of genes mentioned above inPdx-1+BMSCs were higher than that in Pdx-VBMSCs, which was confirmed by Western blotting analysisand RT-PCR. Glucose-inducedinsulin secretion from Pdx-1+BMSCs in 5mmol/L and 25mmol/L glocuse was(56.61 +-4.82) uU/ml and (115.29+-2.56) uU/ml respectively, which were much higher than those fromPdx-1 BMSCs((25.53 +-6.49) uU/mL and (53.26 + 7.56) uU/mL respectively). Grafted animals were ableto maintain their body weight and survive for relatively longer periods of time than hyperglycemicsham-grafted controls, which demonstrated an overall beneficial effect of the grafted cells on thehealth of the animals. These findings thus suggested that exogenous expression of Pdx-1 shouldprovide a promising approach for efficiently producing islet-like cells from BMSCs for the futuretherapeutic use in diabetic patients.

Transplantation of engineered exosomes derived from bone marrow mesenchymal stromal cells ameliorate diabetic peripheral neuropathy under electrical stimulation

Diabetic peripheral neuropathy(DPN)is a long-term complication associated with nerve dysfunction and uncontrolled hyperglycemia.In spite of new drug discoveries,development of effective therapy is much needed to cure DPN.Here,we have developed a combinatorial approach to provide biochemical and electrical cues,considered to be important for nerve regeneration.Exosomes derived from bone marrow mesenchymal stromal cells(BMSCs)were fused with polypyrrole nanoparticles(PpyNps)containing liposomes to deliver both the cues in a single delivery vehicle.We developed DPN rat model and injected intramuscularly the fused exosomal system to understand its long-term therapeutic effect.We found that the fused system along with electrical stimulation normalized the nerve conduction velocity(57.60±0.45 m/s)and compound muscle action potential(16.96±0.73 mV)similar to healthy control(58.53±1.10 m/s;18.19±1.45 mV).Gastrocnemius muscle morphology,muscle mass,and integrity were recovered after treatment.Interestingly,we also observed paracrine effect of delivered exosomes in controlling hyperglycemia and loss in body weight and also showed attenuation of damage to the tissues such as the pancreas,kidney,and liver.This work provides a promising effective treatment and also contribute cutting edge therapeutic approach for the treatment of DPN.

Combination of low-energy shock-wave therapy and bone marrow mesenchymal stem cell transplantation to improve the erectile function of diabetic rats

Stem cell transplantation and low-energy shock-wave therapy （LESWT） have emerged as potential and effective treatment protocols for diabetic erectile dysfunction. During the tracking of transplanted stem cells in diabetic erectile dysfunction models, the number of visible stem cells was rather low and decreased quickly. LESWT could recruit endogenous stem cells to the cavernous body and improve the microenvironment in diabetic cavernous tissue. Thus, we deduced that LESWT might benefit transplanted stem cell survival and improve the effects of stem cell transplantation. In this research, 42 streptozotocin-induced diabetic rats were randomized into four groups： the diabetic group （n = 6）, the LESWT group （n = 6）, the bone marrow-derived mesenchymal stem cell （BMSC） transplantation group （n = 15）, and the combination of LESWT and BMSC transplantation group （n = 15）. One and three days after BMSC transplantation, three rats were randomly chosen to observe the survival numbers of BMSCs in the cavernous body. Four weeks after BMSC transplantation, the following parameters were assessed： the surviving number of transplanted BMSCs in the cavernous tissue, erectile function, real-time polymerase chain reaction, and penile immunohistochemical assessment. Our research found that LESWT favored the survival of transplanted BMSCs in the cavernous body, which might be related to increased stromal cell-derived factor-1 expression and the enhancement of angiogenesis in the diabetic cavernous tissue. The combination of LESWT and BMSC transplantation could improve the erectile function of diabetic erectile function rats more effectively than LESWT or BMSC transplantation performed alone.

程序性细胞死亡受体1影响高糖条件下成骨细胞分化的机制

背景:程序性细胞死亡受体1属于免疫球蛋白基因超家族,可以调控成骨细胞分化、影响骨稳态,然而其在糖尿病性骨质疏松中的调控作用及机制尚不明确。目的:探讨程序性细胞死亡受体1对高糖环境下大鼠骨髓间充质干细胞成骨分化的调控作用及机制。方法:①动物实验:采用随机数字法将12只SD大鼠随机分为对照组(n=6)与模型组(n=6),对照组常规喂养,模型组腹腔注射链脲佐菌素建立1型糖尿病模型,高脂饲料喂养8周建立1型糖尿病性骨质疏松模型。喂养8周后,取2组大鼠股骨,分别进行苏木精-伊红染色、micro-CT检测与程序性细胞死亡受体1、程序性细胞死亡配体1 mNRA表达。②细胞实验:将第3代大鼠骨髓间充质干细胞随机分4组处理:正常对照组、高糖模型组加入低糖培养基,PD-1沉默组转染程序性细胞死亡受体1 siRNA,PD-1沉默空载组转染siRNA-NC。转染48 h后,正常对照组更换为新的低糖培养基,高糖模型组、PD-1沉默组、PD-1沉默空载组更换为高糖培养基,培养48 h后进行成骨诱导培养。成骨诱导21 d后,分别进行茜素红染色、qRT-PCR(程序性细胞死亡受体1、RUNX2 mRNA表达)与Western blot(β-catenin、GSK-3β、p-GSK-3β与Axin2蛋白表达)检测。结果与结论:①动物实验:苏木精-伊红染色与micro-CT检测结果显示,模型组大鼠1型糖尿病骨质疏松造模成功。qRT-PCR检测结果显示,模型组程序性细胞死亡受体1、程序性细胞死亡配体1 mRNA表达均高于对照组(P<0.05)。②细胞实验:茜素红染色结果显示,高糖模型组、PD-1沉默空载组矿化结节形成能力低于对照组、PD-1沉默组。与正常对照组比较,高糖模型组、PD-1沉默空载组程序性细胞死亡受体1 mRNA表达及GSK3β、Axin2蛋白表达均升高(P<0.05),RUNX2 mRNA表达及p-GSK3β、β-catenin蛋白表达均降低(P<0.05);与高糖模型组、PD-1沉默空载组比较,PD-1沉默组程序性细胞死亡受体1 mRNA表达及GSK3β、Axin2蛋白表达均降低(P<0.05),RUNX2 mRNA表达及p-GSK3β、β-catenin蛋白表达均升高(P<0.05)。③结果表明:沉默程序性细胞死亡受体1表达可通过激活Wnt/β-catenin信号通路促进高糖条件下大鼠骨髓间充质干细胞的成骨分化。

糖尿病骨质疏松来源颌骨骨髓间充质干细胞成骨分化能力的研究

目的探究糖尿病骨质疏松来源颌骨骨髓间充质干细胞(rJBMMSCs)成骨分化能力及生物学特性是否发生改变。方法使用GK大鼠建立糖尿病骨质疏松(DOP)模型,建模成功后取大鼠下颌骨提取细胞,并进行干细胞鉴定,以正常Wistar大鼠作为对照组。CCK-8检测细胞增殖能力,平板克隆法检测细胞克隆形成能力,划痕实验检测细胞迁移能力,流式细胞术检测细胞周期。通过碱性磷酸酶(ALP)染色、茜素红(ARS)染色、qRT-PCR以及Westernblot检测其成骨分化能力。结果DOPrJBMMSCs的细胞增殖能力、克隆形成能力、细胞迁移能力均较对照组减弱。ALP染色及活性分析显示DOP组较对照组染色面积小且颜色浅,ALP活性显著降低。ARS染色显示DOP组矿化结节明显较对照组少,其OD值明显小于对照组。qRT-PCR以及Western blot结果显示DOP组的成骨相关因子在mRNA水平及蛋白水平表达均显著下降。结论相较于对照组,DOP rJBMMSCs的生物学特性发生改变,其成骨分化能力明显受损。

二甲双胍对微弧氧化羟基磷灰石涂层金属钛表面的糖尿病大鼠BMSCs细胞增殖和成骨分化的影响及机制研究

目的探究二甲双胍(Met)对微弧氧化羟基磷灰石(MAO-HA)涂层金属钛表面的2型糖尿病(T2DM)大鼠骨髓间充质干细胞(BMSCs)细胞增殖和成骨分化的影响及作用机制。方法20只SPF级雄性大鼠随机分为正常组(NC组)、T2DM组、低剂量二甲双胍组(Met-Low组)、高剂量二甲双胍组(Met-High组),每组5只。采用高糖高脂饲料喂养4周联合腹腔注射链脲佐菌素(STA,50 mg/kg)建立T2DM大鼠模型。Met-Low、Met-high组大鼠分别进行二甲双胍150 mg·kg^(-1)·d^(-1)、300 mg·kg^(-1)·d^(-1)灌胃,NC组、T2DM组以等量0.9%氯化钠溶液灌胃。灌胃4周后,处死大鼠并分离股骨、胫骨中的BMSCs。采用电化学法(ELC)和微弧氧化法(MAO)制备羟基磷灰石(HA)涂层金属钛材料。将正常大鼠来源的BMSCs种植于ELC-HA、MAO-HA涂层表面,培养48 h后,扫描电镜观察涂层表面形态及BMSCs在其表面的吸附情况。将不同来源的BMSCs种植于MAO-HA涂层表面,并分为NC组、T2DM组、Met-Low组、Met-High组。培养48 h后,CCK-8、EdU染色检测BMSCs增殖能力;碱性磷酸酶(ALP)染色、茜素红染色检测BMSCs成骨分化能力;Western blot检测细胞增殖相关标志物[增殖细胞核抗原(PCNA)、Ki67]、成骨分化相关标志物[碱性磷酸酶(ALP)、骨钙素(OCN)、骨桥蛋白(OPN)]、Wnt/βcatenin通路相关蛋白[Wnt3a、β连环蛋白(βcatenin)、糖原合酶激酶-3β(GSK-3β)]蛋白水平。结果MAO-HA涂层表面具有均匀粗糙的孔隙,其上BMSCs充分伸展,细胞突起粗大,而ELC-HA涂层表面十分光滑,其上BMSCs皱缩,突起较细。与NC组相比,T2DM组BMSCs细胞存活率、EdU阳性细胞率及成骨分化能力明显降低,BMSCs中PCNA、Ki67、ALP、OCN、OPN、Wnt3a、βcatenin蛋白水平明显降低,GSK-3β蛋白水平明显升高(均P<0.05)。与T2DM组相比,Met-Low组和Met-High组BMSCs细胞存活率、EdU阳性细胞率及成骨分化能力明显升高,BMSCs中PCNA、Ki67、ALP、OCN、OPN、Wnt3a、βcatenin蛋白水平明显升高,GSK-3β蛋白水平明显降低(均P<0.05)。结论二甲双胍能够促进MAO-HA金属钛表面T2DM大鼠BMSCs增殖和成骨分化能力,其可能通过激活Wnt/βcatenin通路发挥作用。

基于JAK2/STAT3信号通路研究BMSC移植对PDPN的影响

目的探讨骨髓间充质干细胞(bone marrow mesenchymal stemcell,BMSC)移植对痛性糖尿病周围神经病变(painful diabetic peripheral neuropathy,PDPN)大鼠的影响。方法选取SPF级雄性GK大鼠14只,随机分为模型组和治疗组,每组各7只。另选取同周龄、同性别Wistar大鼠7只作为正常组。治疗组大鼠腹腔注射BMSC进行6周治疗。检测热痛阈;取坐骨神经,采用苏木精-伊红(hematoxylin-eosin,HE)染色、Masson染色观察坐骨神经病理学形态改变;采用Western blot法检测JAK2/STAT3信号通路相关蛋白P-JAK2、P-STAT3的表达。结果经BMSC治疗后,大鼠热痛阈值有所上升;坐骨神经损伤被修复,炎性细胞浸润缓解及脱髓腔现象改善;通路相关蛋白p-JAK2、P-STAT3表达下降。结论BMSC移植通过抑制JAK2/STAT3信号通路能减轻炎性反应,修复坐骨神经,缓解疼痛。

Pdx-1、Ngn3联合MafA诱导干细胞分化为胰岛素分泌细胞移植治疗1型糖尿病大鼠的效果

目的通过胰十二指肠同源盒1(Pdx-1)、神经元素3(Ngn3)联合V型肌腱膜纤维肉瘤癌基因同源基因A(MafA)共转染大鼠骨髓间充质干细胞(BMSCs)诱导分化为胰岛素分泌细胞(IPCs),移植治疗1型糖尿病大鼠并观察其疗效。方法Pdx-1、Ngn3和MafA共转染BMSCs诱导为IPCs,链脲佐菌素(STZ)制备45只1型糖尿病SD大鼠模型,BMSCs组(15只)肾被膜下移植2×10^(6) BMSCs,IPCs组(15只)大鼠肾被膜下移植2×10^(6) IPCs,sham-operation组(15只)大鼠肾被膜下注入等量生理盐水,另取15只健康SD大鼠肾被膜下注入等量生理盐水作为normal组。监测各组大鼠移植第0、7、14、21、28 d空腹血糖及体重;第21天对各组大鼠均行葡萄糖耐量试验;第28天取各组大鼠肾脏组织进行免疫组化。结果BMSCs和IPCs组大鼠血糖随时间下降,移植第21天两组大鼠空腹血糖低于移植第0天,且均低于同期sham-operation组(P<0.05),移植第28天IPCs组大鼠空腹血糖低于BMSCs组(P<0.05)。糖尿病大鼠中IPCs组和BMSCs组腹腔葡萄糖耐量实验曲线下面积小于sham-operation组,且IPCs组曲线下面积最小(P<0.05)。BMSCs组和IPCs组大鼠肾脏组织可见棕色荧光的胰岛素表达,且IPCs组胰岛素荧光光密度高于BMSCs组(P<0.05)。结论Pdx-1-Ngn3联合MafA诱导BMSCs形成的IPCs移植后在糖尿病大鼠体内可降低糖尿病大鼠的空腹血糖。

骨髓间充质干细胞外泌体调控NLRP3炎性小体对糖尿病大鼠牙槽骨缺损的机制研究

目的 探究骨髓间充质干细胞外泌体通过调控NLRP3炎性小体信号通路影响糖尿病大鼠牙槽骨缺损愈合相关分子机制。方法 选取50只SD大鼠纳入研究,随机选取10只大鼠作为对照组,其余大鼠构建糖尿病+双侧上颌牙槽骨缺损模型,设置模型组、骨髓间充质干细胞外泌体组(BMMSC-Exos组)、MCC950组(NLRP3抑制剂)、BMMSC-Exos+MCC950组,其中BMMSC-Exos组、MCC950组、BMMSC-Exos+MCC950组SD大鼠分别尾静脉注射BMMSC-Exos及MCC950试剂,模型组注射等量盐水。模型构建28d后取大鼠上颌骨组织。TEM检测BMMSC-Exos形态,Westernblot检测BMMSC-Exos标志性蛋白CD9、CD63、CD81表达。检测各组大鼠空腹血糖水平、HE染色分析各组大鼠牙槽骨炎性浸润及Lance-Sandhu评分;Western blot检测各组大鼠牙槽骨组织内NLRP3炎性小体信号通路关键蛋白(NLRP3、caspase-1、IL-1β)、骨代谢关键蛋白(OPG、ALP、Collal)表达。结果 BMMSC-Exos直径大小在100 nm左右,呈双凹圆盘状态,膜结构完整;与纯BMMSCs相比,BMMSC-Exos标志物蛋白CD9、CD63、CD81的含量表达明显提升(P <0.05)。糖尿病大鼠模型建立成功,BMMSC-Exos干预、NLRP3抑制剂(MCC950)下调大鼠血糖水平(P <0.05);两者联合可以进一步下调大鼠血糖水平(P <0.05);与对照组相比,糖尿病牙槽骨缺损模型建立可以下调骨再生Lane-Sandhu评分、OPG、ALP、Collal的表达(P <0.05),上调NLRP3、caspase-1、IL-1β表达(P <0.05);BMMSC-Exos干预可以再次上调Lane-Sandhu评分及OPG、ALP、Collal蛋白表达(P<0.05),下调NLRP3、caspase-1、IL-1β的表达(P <0.05)。与模型组相比,BMMSC-Exos及MCC950干预后大鼠骨再生Lane-Sandhu评分、骨代谢关键蛋白(OPG、ALP、Collal)的表达提升(P<0.05);两者联合可进一步上调大鼠骨再生Lane-Sandhu评分及骨代谢关键蛋白表达(P <0.05)。结论 骨髓间充质干细胞外泌体通过抑制NLRP3炎症小体活性来改善糖尿病牙槽骨缺损大鼠骨代谢,降低炎症反应,促进骨缺损的愈合。

高糖微环境下miR-449对人骨髓间充质干细胞成骨分化的作用和机制研究

目的探讨miR-449在高糖(HG)作用下对人骨髓间充质干细胞(hBMSCs)成骨分化的影响及其可能的作用机制。方法将hBMSCs接种于成骨培养基培养,诱导其成骨分化。实验组:成骨培养基中加入高糖25 mmol/L,模拟高糖微环境处理。对照组:细胞维持在5 mmol/L葡萄糖的正常培养基中。采用茜素红染色、碱性磷酸酶活性测定、双荧光素酶测定、实时定量PCR(qRT-PCR)检测等方法测定以下指标:(1)miR-449在HG诱导的hBMSCs成骨分化时的表达水平;(2)miR-449模拟物和抑制物对碱性磷酸酶(ALP)活性,成骨相关标志物表达的影响;(3)Sirt1和Fra-1的过表达对miR-449在HG处理的hBMSCs成骨分化标志物表达的影响。结果(1)HG处理的实验组hBMSCs成骨分化低于对照组细胞(P<0.05),miR-449表达水平较对照组降低(P<0.05)。(2)在HG诱导的hBMSCs成骨分化过程中,miR-449模拟物可降低ALP活性(P<0.05),降低成骨标志物的mRNA表达(P<0.05);而miR-449抑制剂能提高成骨标志物的mRNA活性(P<0.05)。(3)miR-449直接靶向结合Sirt1,Sirt1过表达逆转了miR-449模拟物对Fra-1mRNA表达的抑制作用,而Fra-1的过表达减轻了这种抑制作用;过表达Fra-1可减轻miR-449模拟物对ALP活性及成骨标志物mRNA的抑制作用。结论miR-449过表达通过Sirt1/Fra-1信号通路抑制HG处理的hBMSCs的成骨分化;通过调节miR-449可能为糖尿病骨质疏松症的干预提供一种新的治疗方法。

骨髓间充质干细胞来源外泌体miR-30e-5p改善高血糖诱发的肾小管上皮细胞的焦亡

目的探讨骨髓间充质干细胞外泌体(BMSC-exos)miR-30e-5p对高葡萄糖(HG)诱导的体外培养的人肾近端小管细胞(HK-2)焦亡的影响,并探索治疗糖尿病肾病(DKD)的替代方法。方法BMSC-exos分离并内化到HG处理的HK-2细胞中,测定细胞生存能力和细胞毒性。通过流式细胞仪方法评估细胞焦亡,检测miR-30e-5p、IL-1β和IL-18的表达水平,通过Western blotting蛋白质印迹分析测定焦亡相关的细胞因子蛋白。结果BMSC-exos降低了LDH、IL-1β和IL-18的分泌,改善焦亡情况,并抑制了HG诱导的HK-2细胞中的焦亡相关因子(IL-1β、胱天蛋白酶-1、GSDMD-N和NLRP3)的表达。miR-30e-5p敲除逆转了BMSC-exos对HK-2细胞焦亡的改善作用。结论BMSC-exos的miR-30e-5p抑制HG处理的HK-2细胞焦亡,这可能为治疗DKD提供一种新的策略。

纳米细胞囊泡负载姜黄素促进糖尿病小鼠创面的愈合

背景:间充质干细胞来源的外泌体及姜黄素均能促进糖尿病难愈合创面的愈合,但外泌体存在产量低的问题,而姜黄素存在结构相对不稳定、溶解性差等问题,影响了修复效果。目的:观察负载姜黄素的纳米细胞囊泡对糖尿病小鼠难愈合创面的修复效果。方法:分离提取C57BL/6J乳鼠原代骨髓间充质干细胞,使用姜黄素溶液悬浮细胞,采用微型挤出机制备出负载姜黄素的纳米细胞囊泡,检测囊泡的包封率与载药量。①体外实验:采用细胞计数法检测不同质量浓度(0,10,20,40,80 mg/L)纳米细胞囊泡对成纤维细胞NIH-3T3增殖的作用,Transwell实验检测纳米细胞囊泡(40 mg/L)对成纤维细胞迁移能力的影响。检测姜黄素对脂多糖诱导的RAW 264.7巨噬细胞炎症因子——肿瘤坏死因子α、白细胞介素6 mRNA表达量的影响。②体内实验:取24只成年C57BL/6J小鼠,腹腔注射链脲佐菌素建立糖尿病模型,造模成功后于背部制作2个直径6 mm的创面,A组注射PBS,B组注射纳米细胞囊泡,C组注射姜黄素溶液,D组注射负载姜黄素的纳米细胞囊泡,每组6只,观察创面愈合情况与组织形态学变化。结果与结论:①囊泡的包封率为42%,载药率为2.3%;不同质量浓度的纳米细胞囊泡均可促进成纤维细胞的增殖,其中以40 mg/L效果最明显;40 mg/L的纳米细胞囊泡可促进成纤维细胞的迁移;姜黄素降低了脂多糖刺激的巨噬细胞的炎症反应;②创面造模14 d后,B、C、D组创面明显缩小,其中D组创面面积最小;苏木精-伊红与Masson染色显示,创面造模后7 d,B、C、D组创面有大量的肉芽组织形成与胶原纤维沉积,其中以D组最多;创面造模后14 d,B、C、D组创面的肉芽组织形成与胶原纤维沉积进一步增多,其中以D组最多;③结果表明,负载姜黄素的纳米细胞囊泡可发挥纳米细胞囊泡和姜黄素的协同作用,促进糖尿病创面的愈合。

2型糖尿病对大鼠颌骨骨髓间充质干细胞生物学特性的影响及其机制研究

背景2型糖尿病患者骨代谢异常,颌骨骨质和骨量都发生明显改变,是牙周炎的全身促进因素之一。Wnt信号通路可以促进干细胞矿化并修复骨组织缺损。然而2型糖尿病影响下Wnt信号通路是否参与了对颌骨骨髓间充质干细胞(jaw bone marrow mesenchymal stem cells,JBMMSCs)的成骨分化调控仍未可知。目的研究2型糖尿病对大鼠JBMMSCs增殖及分化等生物学特性的影响,并对其机制进行初步探索。方法选取连续两周随机血糖≥16.7mmoL/L的13周龄GK大鼠为2型糖尿病组,相同周龄的Wistar大鼠作为对照组,两组各10只;无菌条件下采用骨髓冲洗法与骨片消化法相结合的方法分离培养两组JBMMSCs作为研究对象。CCK-8法检测并比较两组细胞增殖能力,流式细胞术检测细胞被诱导凋亡的能力。对JBMMSCs进行成骨、成脂诱导后,qRT-PCR评估成骨、成脂及Wnt信号通路相关基因的表达改变,碱性磷酸酶(alkaline phosphatase,ALP)染色检测成骨诱导后ALP的表达变化,茜素红染色比较钙结节形成能力,油红O染色检测成脂诱导后脂滴形成能力。结果与对照组相比,2型糖尿病组JBMMSCs的增殖及克隆形成能力降低,凋亡早期与晚期的细胞比例增加(P<0.05)。两组JBMMSCs成骨诱导后成骨相关基因ALP、OCN和Runx2 mRNA表达升高,但2型糖尿病组低于对照组(P<0.05),2型糖尿病组钙结节形成能力和ALP染色面积及密度较对照组低(P<0.05)。成脂诱导后,成脂相关基因的表达和脂滴的形成较对照组减少(P<0.05)。2型糖尿病组JBMMSCs成骨诱导7 d后Wnt信号通路相关分子Wnt4、Wnt5a、Wnt7b的mRNA表达较对照组升高,β-catenin的表达水平较对照组低。结论2型糖尿病影响大鼠颌骨骨髓间充质干细胞的增殖和克隆、抑制成骨及成脂分化能力,其成骨能力的降低可能与Wnt信号通路相关。