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1.
Stem Cell Res Ther ; 15(1): 120, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38659015

RESUMO

BACKGROUND: Diabetic cardiomyopathy (DCM) is a serious health-threatening complication of diabetes mellitus characterized by myocardial fibrosis and abnormal cardiac function. Human umbilical cord mesenchymal stromal cells (hUC-MSCs) are a potential therapeutic tool for DCM and myocardial fibrosis via mechanisms such as the regulation of microRNA (miRNA) expression and inflammation. It remains unclear, however, whether hUC-MSC therapy has beneficial effects on cardiac function following different durations of diabetes and which mechanistic aspects of DCM are modulated by hUC-MSC administration at different stages of its development. This study aimed to investigate the therapeutic effects of intravenous administration of hUC-MSCs on DCM following different durations of hyperglycemia in an experimental male model of diabetes and to determine the effects on expression of candidate miRNAs, target mRNA and inflammatory mediators. METHODS: A male mouse model of diabetes was induced by multiple low-dose streptozotocin injections. The effects on severity of DCM of intravenous injections of hUC-MSCs and saline two weeks previously were compared at 10 and 18 weeks after diabetes induction. At both time-points, biochemical assays, echocardiography, histopathology, polymerase chain reaction (PCR), immunohistochemistry and enzyme-linked immunosorbent assays (ELISA) were used to analyze blood glucose, body weight, cardiac structure and function, degree of myocardial fibrosis and expression of fibrosis-related mRNA, miRNA and inflammatory mediators. RESULTS: Saline-treated diabetic male mice had impaired cardiac function and increased cardiac fibrosis after 10 and 18 weeks of diabetes. At both time-points, cardiac dysfunction and fibrosis were improved in hUC-MSC-treated mice. Pro-fibrotic indicators (α-SMA, collagen I, collagen III, Smad3, Smad4) were reduced and anti-fibrotic mediators (FGF-1, miRNA-133a) were increased in hearts of diabetic animals receiving hUC-MSCs compared to saline. Increased blood levels of pro-inflammatory cytokines (IL-6, TNF, IL-1ß) and increased cardiac expression of IL-6 were also observed in saline-treated mice and were reduced by hUC-MSCs at both time-points, but to a lesser degree at 18 weeks. CONCLUSION: Intravenous injection of hUC-MSCs ameliorated key functional and structural features of DCM in male mice with diabetes of shorter and longer duration. Mechanistically, these effects were associated with restoration of intra-myocardial expression of miRNA-133a and its target mRNA COL1AI as well as suppression of systemic and localized inflammatory mediators.


Assuntos
Diabetes Mellitus Experimental , Cardiomiopatias Diabéticas , Fibrose , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , MicroRNAs , Miocárdio , Cordão Umbilical , Animais , Humanos , Masculino , Camundongos , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Experimental/metabolismo , Cardiomiopatias Diabéticas/terapia , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/patologia , Cardiomiopatias Diabéticas/genética , Fibrose/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Cordão Umbilical/citologia , Cordão Umbilical/metabolismo
2.
Stem Cell Res Ther ; 15(1): 66, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443965

RESUMO

BACKGROUND AND AIMS: Mesenchymal stromal cells (MSCs) a potentially effective disease-modulating therapy for diabetic nephropathy (DN) but their clinical translation has been hampered by incomplete understanding of the optimal timing of administration and in vivo mechanisms of action. This study aimed to elucidate the reno-protective potency and associated mechanisms of single intravenous injections of human umbilical cord-derived MSCs (hUC-MSCs) following shorter and longer durations of diabetes. METHODS: A streptozotocin (STZ)-induced model of diabetes and DN was established in C57BL/6 mice. In groups of diabetic animals, human (h)UC-MSCs or vehicle were injected intravenously at 8 or 16 weeks after STZ along with vehicle-injected non-diabetic animals. Diabetes-related kidney abnormalities was analyzed 2 weeks later by urine and serum biochemical assays, histology, transmission electron microscopy and immunohistochemistry. Serum concentrations of pro-inflammatory and pro-fibrotic cytokines were quantified by ELISA. The expression of autophagy-related proteins within the renal cortices was investigated by immunoblotting. Bio-distribution of hUC-MSCs in kidney and other organs was evaluated in diabetic mice by injection of fluorescent-labelled cells. RESULTS: Compared to non-diabetic controls, diabetic mice had increases in urine albumin creatinine ratio (uACR), mesangial matrix deposition, podocyte foot process effacement, glomerular basement membrane thickening and interstitial fibrosis as well as reduced podocyte numbers at both 10 and 18 weeks after STZ. Early (8 weeks) hUC-MSC injection was associated with reduced uACR and improvements in multiple glomerular and renal interstitial abnormalities as well as reduced serum IL-6, TNF-α, and TGF-ß1 compared to vehicle-injected animals. Later (16 weeks) hUC-MSC injection also resulted in reduction of diabetes-associated renal abnormalities and serum TGF-ß1 but not of serum IL-6 and TNF-α. At both time-points, the kidneys of vehicle-injected diabetic mice had higher ratio of p-mTOR to mTOR, increased abundance of p62, lower abundance of ULK1 and Atg12, and reduced ratio of LC3B to LC3A compared to non-diabetic animals, consistent with diabetes-associated suppression of autophagy. These changes were largely reversed in the kidneys of hUC-MSC-injected mice. In contrast, neither early nor later hUC-MSC injection had effects on blood glucose and body weight of diabetic animals. Small numbers of CM-Dil-labeled hUC-MSCs remained detectable in kidneys, lungs and liver of diabetic mice at 14 days after intravenous injection. CONCLUSIONS: Single intravenous injections of hUC-MSCs ameliorated glomerular abnormalities and interstitial fibrosis in a mouse model of STZ-induced diabetes without affecting hyperglycemia, whether administered at relatively short or longer duration of diabetes. At both time-points, the reno-protective effects of hUC-MSCs were associated with reduced circulating TGF-ß1 and restoration of intra-renal autophagy.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Rim/anormalidades , Células-Tronco Mesenquimais , Anormalidades Urogenitais , Humanos , Animais , Camundongos , Camundongos Endogâmicos C57BL , Nefropatias Diabéticas/terapia , Injeções Intravenosas , Fator de Crescimento Transformador beta1 , Diabetes Mellitus Experimental/terapia , Interleucina-6 , Fator de Necrose Tumoral alfa , Autofagia , Fibrose , Serina-Treonina Quinases TOR
3.
Stem Cell Res Ther ; 15(1): 67, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38444003

RESUMO

BACKGROUND: Spinal cord injury (SCI) is a serious clinical condition that has pathological changes such as increased neuroinflammation and nerve tissue damage, which eventually manifests as fibrosis of the injured segment and the development of a spinal cord cavity leading to loss of function. Cell-based therapy, such as mesenchymal stem cells (MSCs) and neural stem cells (NSCs) are promising treatment strategies for spinal cord injury via immunological regulation and neural replacement respectively. However, therapeutic efficacy is rare reported on combined transplantation of MSC and NSC in acute mice spinal cord injury even the potential reinforcement might be foreseen. Therefore, this study was conducted to investigate the safety and efficacy of co-transplanting of MSC and NSC sheets into an SCI mice model on the locomotor function and pathological changes of injured spinal cord. METHODS: To evaluate the therapeutic effects of combination cells, acute SCI mice model were established and combined transplantation of hiPSC-NSCs and hMSCs into the lesion site immediately after the injury. Basso mouse scale was used to perform the open-field tests of hind limb motor function at days post-operation (dpo) 1, 3, 5, and 7 after SCI and every week after surgery. Spinal cord and serum samples were collected at dpo 7, 14, and 28 to detect inflammatory and neurotrophic factors. Hematoxylin-eosin (H&E) staining, masson staining and transmission electron microscopy were used to evaluate the morphological changes, fibrosis area and ultrastructure of the spinal cord. RESULT: M&N transplantation reduced fibrosis formation and the inflammation level while promoting the secretion of nerve growth factor and brain-derived neurotrophic factor. We observed significant reduction in damaged tissue and cavity area, with dramatic improvement in the M&N group. Compared with the Con group, the M&N group exhibited significantly improved behaviors, particularly limb coordination. CONCLUSION: Combined transplantation of hiPSC-NSC and hMSC could significantly ameliorate neuroinflammation, promote neuroregeneration, and decrease spinal fibrosis degree in safe and effective pattern, which would be indicated as a novel potential cell treatment option.


Assuntos
Células-Tronco Pluripotentes Induzidas , Traumatismos da Medula Espinal , Animais , Camundongos , Doenças Neuroinflamatórias , Traumatismos da Medula Espinal/terapia , Modelos Animais de Doenças , Fibrose
4.
Stem Cell Res ; 72: 103201, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37856927

RESUMO

In this study, fibroblasts were harvested and isolated from a healthy 14-year-old male donor and reprogrammed with four Yamanaka factors containing Oct3/4, Sox2, Klf4 and c-Myc to generate human induced pluripotent stem cell (iPSC) lines. The resulting iPSCs were integration-free, expressed normal karyotype, displayed pluripotency markers, and have been demonstrated to differentiate into cells with three germ layer. And the iPSCs were further differentiated to chondrosphere in vivo. The models could be used to test multiple differentiation protocols and also as a control for screening drugs and studying cartilage related disease.


Assuntos
Células-Tronco Pluripotentes Induzidas , Masculino , Humanos , Adolescente , Células-Tronco Pluripotentes Induzidas/metabolismo , Diferenciação Celular , Fibroblastos/metabolismo , Células Cultivadas , Proteínas Proto-Oncogênicas c-myc/genética , Reprogramação Celular
5.
Oxid Med Cell Longev ; 2022: 6483582, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36046683

RESUMO

Background: Astrocytes can be involved in motor neuron toxicity in amyotrophic lateral sclerosis (ALS) induced by noncell autonomous effects, and inflammatory cytokines may play the main role in mediating this process. However, the etiology of aberrant cytokine secretion is unclear. The present study assessed possible involvement of the mTOR-autophagy pathway in aberrant cytokine secretion by ALS patient iPSC-derived astrocytes. Method and Results. PBMCs from sporadic ALS patients and control subjects were reprogrammed into iPSCs, which were then differentiated into astrocytes and/or motor neurons. Comparison with control astrocytes indicated that conditioned medium of ALS astrocytes reduced the viability of the control motor neurons (p < 0.05) assessed using the MTT assay. The results of ELISA showed that the concentrations of TNFα, IL1ß, and IL6 in cell culture medium of ALS astrocytes were increased (p < 0.05). ALS astrocytes had higher p62 and mTOR levels and lower LC3BII/LC3BI ratio and ULK1 and p-Beclin-1 (Ser15) levels (p < 0.05), indicating defective autophagy. Exogenous inhibition of the mTOR-autophagy pathway, but not the activation of the pathway in control subject astrocytes, increased the levels of p62 and mTOR and concentration of IL-1ß, TNF-α, and IL-6 in cell culture medium and decreased the LC3BII/LC3BI ratio and levels of ULK1 and p-Beclin-1 (Ser15), and these changes were comparable to those in ALS astrocytes. After 48 h of rapamycin (autophagy activator) and 3-methyladenine (autophagy inhibitor) treatments, the exogenous activation of the mTOR-autophagy pathway, but not inhibition of the pathway, in ALS astrocytes significantly reduced the concentrations of TNFα, IL1ß, and IL6 in cell culture medium and reduced the levels of p62, while increasing the levels of LC3B-II/LC3B-I, ULK1, and p-Beclin-1 (Ser15), and these changes were comparable to those in control subject astrocytes. Conclusion: Alteration in the mTOR/ULK1/Beclin-1 pathway regulated cytokine secretion in ALS astrocytes, which was able to lead to noncell autonomous toxicity. Autophagy activation mitigated cytokine secretion by ALS astrocytes.


Assuntos
Esclerose Lateral Amiotrófica , Células-Tronco Pluripotentes Induzidas , Esclerose Lateral Amiotrófica/metabolismo , Astrócitos/metabolismo , Autofagia , Proteína Beclina-1/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Interleucina-6/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
6.
Stem Cell Res ; 57: 102613, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34871962

RESUMO

In this study, skin biopsy was, and the fibroblasts were isolated from the dermal explant cultures. Human induced pluripotent stem cell (iPSC) line was generated from the skin fibroblasts collected from a healthy 50-year old male donor with informed consent. The reprogramming of fibroblasts was performed with four Yamanaka factors containing Oct3/4, Sox2, Klf4 and c-Myc. The generated iPSCs were confirmed integration-free, expressed pluripotency markers, displayed the normal karyotype, and demonstrated trilineage differentiation potential. This iPSC model can be used to model physiological processes and screen drug validation in vitro.

7.
Stem Cell Res ; 53: 102339, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33892291

RESUMO

In this study, skin biopsy was collected from a healthy 48-year old male donor with informed consent, and the fibroblasts were isolated from the dermal explant cultures. Here, a human induced pluripotent stem cell (iPSC) line was derived from the fibroblasts using the reprogramming four Yamanaka factors (Oct3/4, Sox2, Klf4, c-Myc). The generated iPSCs were integration-free, displayed the normal karyotype, expressed pluripotency markers and demonstrated trilineage differentiation potential in vitro. This iPSC model will be useful for investigating physiological processes, drug validation as well as a control in pathological mechanistic studies.


Assuntos
Células-Tronco Pluripotentes Induzidas , Diferenciação Celular , Reprogramação Celular , Fibroblastos , Humanos , Fator 4 Semelhante a Kruppel , Masculino , Pessoa de Meia-Idade , Pele
8.
Stem Cell Res Ther ; 12(1): 172, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33706803

RESUMO

BACKGROUND: Spinal cord injury (SCI) is a common disease that results in motor and sensory disorders and even lifelong paralysis. The transplantation of stem cells, such as embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), mesenchymal stem cells (MSCs), or subsequently generated stem/progenitor cells, is predicted to be a promising treatment for SCI. In this study, we aimed to investigate effect of human iPSC-derived neural stem cells (hiPSC-NSCs) and umbilical cord-derived MSCs (huMSCs) in a mouse model of acute SCI. METHODS: Acute SCI mice model were established and were randomly treated as phosphate-buffered saline (PBS) (control group), repaired with 1 × 105 hiPSC-NSCs (NSC group), and 1 × 105 huMSCs (MSC group), respectively, in a total of 54 mice (n = 18 each). Hind limb motor function was evaluated in open-field tests using the Basso Mouse Scale (BMS) at days post-operation (dpo) 1, 3, 5, and 7 after spinal cord injury, and weekly thereafter. Spinal cord and serum samples were harvested at dpo 7, 14, and 21. Haematoxylin-eosin (H&E) staining and Masson staining were used to evaluate the morphological changes and fibrosis area. The differentiation of the transplanted cells in vivo was evaluated with immunohistochemical staining. RESULTS: The hiPSC-NSC-treated group presented a significantly smaller glial fibrillary acidic protein (GFAP) positive area than MSC-treated mice at all time points. Additionally, MSC-transplanted mice had a similar GFAP+ area to mice receiving PBS. At dpo 14, the immunostained hiPSC-NSCs were positive for SRY-related high-mobility-group (HMG)-box protein-2 (SOX2). Furthermore, the transplanted hiPSC-NSCs differentiated into GFAP-positive astrocytes and beta-III tubulin-positive neurons, whereas the transplanted huMSCs differentiated into GFAP-positive astrocytes. In addition, hiPSC-NSC transplantation reduced fibrosis formation and the inflammation level. Compared with the control or huMSC transplanted group, the group with transplantation of hiPSC-NSCs exhibited significantly improved behaviours, particularly limb coordination. CONCLUSIONS: HiPSC-NSCs promote functional recovery in mice with acute SCI by replacing missing neurons and attenuating fibrosis, glial scar formation, and inflammation.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Neurais , Traumatismos da Medula Espinal , Animais , Diferenciação Celular , Células-Tronco Pluripotentes Induzidas/transplante , Camundongos , Células-Tronco Neurais/transplante , Recuperação de Função Fisiológica , Medula Espinal , Traumatismos da Medula Espinal/terapia
9.
PLoS One ; 16(3): e0247662, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33705413

RESUMO

BACKGROUND: Diabetes mellitus as a chronic metabolic disease is threatening human health seriously. Although numerous clinical trials have been registered for the treatment of diabetes with stem cells, no articles have been published to summarize the efficacy and safety of mesenchymal stem cells (MSCs) in randomized controlled trials (RCTs). METHODS AND FINDINGS: The aim of this study was to systematically review the evidence from RCTs and, where possible, conduct meta-analyses to provide a reliable numerical summary and the most comprehensive assessment of therapeutic efficacy and safety with MSCs in diabetes. PubMed, Web of Science, Ovid, the Cochrane Library and CNKI were searched. The retrieval time was from establishment of these databases to January 4, 2020. Seven RCTs were eligible for analysis, including 413 participants. Meta-analysis results showed that there were no significant differences in the reduction of fasting plasma glucose (FPG) compared to the baseline [mean difference (MD) = -1.05, 95% confidence interval (CI) (-2.26,0.16), P<0.01, I2 = 94%] and the control group [MD = -0.62, 95%CI (-1.46,0.23), P<0.01, I2 = 87%]. The MSCs treatment group showed a significant decrease in hemoglobin (Hb) A1c [random-effects, MD = -1.32, 95%CI (-2.06, -0.57), P<0.01, I2 = 90%] after treatment. Additionally, HbA1c reduced more significantly in MSC treatment group than in control group [random-effects, MD = -0.87, 95%CI (-1.53, -0.22), P<0.01, I2 = 82%] at the end of follow-up. However, as for fasting C-peptide levels, the estimated pooled MD showed that there was no significant increase [MD = -0.07, 95%CI (-0.30, 0.16), P<0.01, I2 = 94%] in MSCs treatment group compared with that in control group. Notably, there was no significant difference in the incidence of adverse events between MSCs treatment group and control group [relative risk (RR) = 0.98, 95%CI (0.72, 1.32), P = 0.02, I2 = 70%]. The most commonly observed adverse reaction in the MSC treatment group was hypoglycemia (29.95%). CONCLUSIONS: This meta-analysis revealed MSCs therapy may be an effective and safe intervention in subjects with diabetes. However, due to the limited studies, a number of high-quality as well as large-scale RCTs should be performed to confirm these conclusions.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 2/terapia , Hemoglobinas Glicadas/metabolismo , Controle Glicêmico/métodos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/fisiologia , Glicemia/metabolismo , Peptídeo C/sangue , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/patologia , Jejum , Humanos , Hipoglicemia/sangue , Hipoglicemia/diagnóstico , Hipoglicemia/etiologia , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
10.
Dalton Trans ; 47(27): 9051-9056, 2018 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-29931007

RESUMO

A multiply photoactive compound has been developed based on quaternized 1,2-bis(4'-pyridyl)ethylene, which exhibits a hierarchical photoreaction by controlling light intensity. Weak ultraviolet light can effectively promote the cycloaddition reaction with fluorescence enhancement, while stronger ultraviolet light can stimulate a complex response of cycloaddition and electron-transfer which shows turn-off luminescence and coloration. Photofacilitated bleaching of the colored products has been observed for the first time in the pyridinium family.

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