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1.
Int J Mol Sci ; 25(9)2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38732257

RESUMO

In transplantation, hypothermic machine perfusion (HMP) has been shown to be superior to static cold storage (SCS) in terms of functional outcomes. Ex vivo machine perfusion offers the possibility to deliver drugs or other active substances, such as Mesenchymal Stem Cells (MSCs), directly into an organ without affecting the recipient. MSCs are multipotent, self-renewing cells with tissue-repair capacities, and their application to ameliorate ischemia- reperfusion injury (IRI) is being investigated in several preclinical and clinical studies. The aim of this study was to introduce MSCs into a translational model of hypothermic machine perfusion and to test the efficiency and feasibility of this method. Methods: three rodent kidneys, six porcine kidneys and three human kidneys underwent HMP with 1-5 × 106 labelled MSCs within respective perfusates. Only porcine kidneys were compared to a control group of 6 kidneys undergoing HMP without MSCs, followed by mimicked reperfusion with whole blood at 37 °C for 2 h for all 12 kidneys. Reperfusion perfusate samples were analyzed for levels of NGAL and IL-ß by ELISA. Functional parameters, including urinary output, oxygen consumption and creatinine clearance, were compared and found to be similar between the MSC treatment group and the control group in the porcine model. IL-1ß levels were higher in perfusate and urine samples in the MSC group, with a median of 285.3 ng/mL (IQR 224.3-407.8 ng/mL) vs. 209.2 ng/mL (IQR 174.9-220.1), p = 0.51 and 105.3 ng/mL (IQR 71.03-164.7 ng/mL) vs. 307.7 ng/mL (IQR 190.9-349.6 ng/mL), p = 0.16, respectively. MSCs could be traced within the kidneys in all models using widefield microscopy after HMP. The application of Mesenchymal Stem Cells in an ex vivo hypothermic machine perfusion setting is feasible, and MSCs can be delivered into the kidney grafts during HMP. Functional parameters during mimicked reperfusion were not altered in treated kidney grafts. Changes in levels of IL-1ß suggest that MSCs might have an effect on the kidney grafts, and whether this leads to a positive or a negative outcome on IRI in transplantation needs to be determined in further experiments.


Assuntos
Transplante de Rim , Rim , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Perfusão , Traumatismo por Reperfusão , Animais , Suínos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Rim/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos , Perfusão/métodos , Humanos , Transplante de Rim/métodos , Traumatismo por Reperfusão/terapia , Traumatismo por Reperfusão/metabolismo , Preservação de Órgãos/métodos , Pesquisa Translacional Biomédica , Masculino , Hipotermia Induzida/métodos
2.
Brain Behav ; 14(5): e3504, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38698583

RESUMO

BACKGROUND: Electroacupuncture (EA) has been shown to facilitate brain plasticity-related functional recovery following ischemic stroke. The functional magnetic resonance imaging technique can be used to determine the range and mode of brain activation. After stroke, EA has been shown to alter brain connectivity, whereas EA's effect on brain network topology properties remains unclear. An evaluation of EA's effects on global and nodal topological properties in rats with ischemia reperfusion was conducted in this study. METHODS AND RESULTS: There were three groups of adult male Sprague-Dawley rats: sham-operated group (sham group), middle cerebral artery occlusion/reperfusion (MCAO/R) group, and MCAO/R plus EA (MCAO/R + EA) group. The differences in global and nodal topological properties, including shortest path length, global efficiency, local efficiency, small-worldness index, betweenness centrality (BC), and degree centrality (DC) were estimated. Graphical network analyses revealed that, as compared with the sham group, the MCAO/R group demonstrated a decrease in BC value in the right ventral hippocampus and increased BC in the right substantia nigra, accompanied by increased DC in the left nucleus accumbens shell (AcbSh). The BC was increased in the right hippocampus ventral and decreased in the right substantia nigra after EA intervention, and MCAO/R + EA resulted in a decreased DC in left AcbSh compared to MCAO/R. CONCLUSION: The results of this study provide a potential basis for EA to promote cognitive and motor function recovery after ischemic stroke.


Assuntos
Eletroacupuntura , Infarto da Artéria Cerebral Média , Imageamento por Ressonância Magnética , Ratos Sprague-Dawley , Traumatismo por Reperfusão , Animais , Eletroacupuntura/métodos , Masculino , Ratos , Traumatismo por Reperfusão/fisiopatologia , Traumatismo por Reperfusão/terapia , Traumatismo por Reperfusão/diagnóstico por imagem , Infarto da Artéria Cerebral Média/terapia , Infarto da Artéria Cerebral Média/fisiopatologia , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Isquemia Encefálica/terapia , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/diagnóstico por imagem , Modelos Animais de Doenças , Rede Nervosa/fisiopatologia , Rede Nervosa/diagnóstico por imagem , AVC Isquêmico/terapia , AVC Isquêmico/fisiopatologia , AVC Isquêmico/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Hipocampo/fisiopatologia
3.
Zhen Ci Yan Jiu ; 49(4): 391-397, 2024 Apr 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38649207

RESUMO

OBJECTIVES: To observe the effect of electroacupuncture (EA) at "Baihui" (GV20) and "Shenting" (GV24) on the rats' behavior and the transforming precursor of brain-derived neurotrophic factor (proBDNF) into mature brain-derived neurotrophic factor (mBDNF) in the hippocampus of rats with learning and memory impairment induced by cerebral ischemia-reperfusion (IR), so as to explore its mechanisms underlying improvement of learning and memory ability. METHODS: SD rats were randomly divided into blank, sham operation, model, and EA groups, with 6 rats in each group. The model of IR was established by occlusion of the middle cerebral artery. EA (1 Hz/20 Hz) was applied to GV24 and GV20 for 30 min, once daily for 14 days. The neurological function was evaluated according to the Zea Longa's score criteria 24 h after modeling and after intervention. Morris water maze test was used to detect the learning and memory function of the rats. TTC staining was used to evaluate the cerebral infarction volume on the affected side. The protein expression levels of proBDNF, mBDNF, tissue plasminogen activator (tPA), tyrosine kinase receptor B (TrkB) and p75 neurotrophin receptor (p75NTR) in hippocampal tissue were detected by Western blot. RESULTS: Compared with the sham operation group, the neurological function score, the percentage of cerebral infarction volume and the expression levels of proBDNF and p75NTR protein in hippocampus were increased (P<0.01), while the times of crossing the original platform and the total distance in the target quadrant, the expression levels of mBDNF, TrkB and tPA protein and the ratio of mBDNF/proBDNF were decreased (P<0.01, P<0.05) in the model group. Compared with the model group, the neurological function score, the percentage of cerebral infarction volume, and the expression levels of proBDNF and p75NTR protein in hippocampus were decreased (P<0.01, P<0.05), while the times of crossing the original platform, the total distance in the target quadrant, and the expression levels of mBDNF, TrkB and tPA protein and the ratio of mBDNF/proBDNF were increased (P<0.05, P<0.01) in the EA group. CONCLUSIONS: EA can alleviate learning and memory impairment in IR rats, which may be related to its function in up-regulating the expression of tPA protein and promoting the transformation of proBDNF to mBDNF, thus improving the synaptic plasticity.


Assuntos
Isquemia Encefálica , Fator Neurotrófico Derivado do Encéfalo , Eletroacupuntura , Transtornos da Memória , Plasticidade Neuronal , Precursores de Proteínas , Traumatismo por Reperfusão , Animais , Humanos , Masculino , Ratos , Pontos de Acupuntura , Isquemia Encefálica/metabolismo , Isquemia Encefálica/terapia , Isquemia Encefálica/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Hipocampo/metabolismo , Aprendizagem , Memória , Transtornos da Memória/terapia , Transtornos da Memória/metabolismo , Transtornos da Memória/etiologia , Ratos Sprague-Dawley , Receptor trkB/metabolismo , Receptor trkB/genética , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/terapia , Traumatismo por Reperfusão/genética
4.
Stem Cell Res Ther ; 15(1): 119, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38659070

RESUMO

BACKGROUND: Adipose stromal cells (ASC) are a form of mesenchymal stromal cells that elicit effects primarily via secreted factors, which may have advantages for the treatment of injury or disease. Several previous studies have demonstrated a protective role for MSC/ASC on mitigating acute kidney injury but whether ASC derived factors could hasten recovery from established injury has not been evaluated. METHODS: We generated a concentrated secretome (CS) of human ASC under well-defined conditions and evaluated its ability to improve the recovery of renal function in a preclinical model of acute kidney injury (AKI) in rats. 24 h following bilateral ischemia/reperfusion (I/R), rats were randomized following determination of plasma creatinine into groups receiving vehicle -control or ASC-CS treatment by subcutaneous injection (2 mg protein/kg) and monitored for evaluation of renal function, structure and inflammation. RESULTS: Renal function, assessed by plasma creatinine levels, recovered faster in ASC-CS treated rats vs vehicle. The most prominent difference between the ASC-CS treated vs vehicle was observed in rats with the most severe degree of initial injury (Pcr > 3.0 mg/dl 24 h post I/R), whereas rats with less severe injury (Pcr < 2.9 mg/dl) recovered quickly regardless of treatment. The quicker recovery of ASC-treated rats with severe injury was associated with less tissue damage, inflammation, and lower plasma angiopoietin 2. In vitro, ASC-CS attenuated the activation of the Th17 phenotype in lymphocytes isolated from injured kidneys. CONCLUSIONS: Taken together, these data suggest that ASC-CS represents a potent therapeutic option to improve established AKI.


Assuntos
Injúria Renal Aguda , Inflamação , Injúria Renal Aguda/terapia , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Animais , Ratos , Humanos , Inflamação/patologia , Inflamação/metabolismo , Masculino , Secretoma/metabolismo , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Ratos Sprague-Dawley , Injeções Subcutâneas , Rim/metabolismo , Rim/patologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/terapia , Células Estromais/metabolismo
5.
Int Immunopharmacol ; 132: 112030, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38603861

RESUMO

Mast cells (MCs) play a significant role in various diseases, and their activation and degranulation can trigger inflammatory responses and barrier damage. Several studies have indicated that vagus nerve stimulation (VNS) exerts ameliorates neurological injury, and regulates gut MC degranulation. However, there is limited research on the modulatory effect of VNS on MCs in both the gut and brain in brain ischemia-reperfusion (I/R) injury in this process. We aim to develop a minimally invasive, targeted and convenient VNS approach to assess the impact of VNS and to clarify the relationship between VNS and MCs on the prognosis of acute ischemic stroke. We utilized middle cerebral artery occlusion/reperfusion (MCAO/r) to induce brain I/R injury. After the experiment, the motor function and neurofunctional impairments of the rats were detected, and the gastrointestinal function, blood-brain barrier (BBB) and intestinal barrier damage, and systemic and local inflammation were evaluated by Nissl, TTC staining, Evans blue, immunofluorescence staining, transmission electron microscopy, western blot assays, ELISA, and fecal 16S rRNA sequencing methods. Our research confirmed that our minimally invasive VNS method is a novel approach for stimulating the vagus nerve. VNS alleviated motor deficits and gastrointestinal dysfunction while also suppressing intestinal and neuroinflammation. Additionally, VNS ameliorated gut microbiota dysbiosis in rats. Furthermore, our analysis indicated that VNS reduces chymase secretion by modulating MCs degranulation and improves intestinal and BBB damage. Our results showed that VNS treatment can alleviate the damage of BBB and colonic barrier after cerebral I/R by modulating mast cell degranulation, and alleviates systemic inflammatory responses.


Assuntos
Barreira Hematoencefálica , Eixo Encéfalo-Intestino , Degranulação Celular , Microbioma Gastrointestinal , AVC Isquêmico , Mastócitos , Ratos Sprague-Dawley , Traumatismo por Reperfusão , Estimulação do Nervo Vago , Animais , Mastócitos/imunologia , Estimulação do Nervo Vago/métodos , Masculino , Ratos , Traumatismo por Reperfusão/terapia , Traumatismo por Reperfusão/imunologia , AVC Isquêmico/terapia , Eixo Encéfalo-Intestino/fisiologia , Infarto da Artéria Cerebral Média/terapia , Modelos Animais de Doenças , Isquemia Encefálica/terapia , Isquemia Encefálica/imunologia
6.
J Transl Med ; 22(1): 230, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38433198

RESUMO

BACKGROUND: Mitochondrial transplantation (MTx) has emerged as a novel therapeutic strategy, particularly effective in diseases characterized by mitochondrial dysfunction. This review synthesizes current knowledge on MTx, focusing on its role in modulating immune responses and explores its potential in treating post-cardiac arrest syndrome (PCAS). METHODS: We conducted a comprehensive narrative review of animal and human studies that have investigated the effects of MTx in the context of immunomodulation. This included a review of the immune responses following critical condition such as ischemia reperfusion injury, the impact of MTx on these responses, and the therapeutic potential of MTx in various conditions. RESULTS: Recent studies indicate that MTx can modulate complex immune responses and reduce ischemia-reperfusion injury post-CA, suggesting MTx as a novel, potentially more effective approach. The review highlights the role of MTx in immune modulation, its potential synergistic effects with existing treatments such as therapeutic hypothermia, and the need for further research to optimize its application in PCAS. The safety and efficacy of autologous versus allogeneic MTx, particularly in the context of immune reactions, are critical areas for future investigation. CONCLUSION: MTx represents a promising frontier in the treatment of PCAS, offering a novel approach to modulate immune responses and restore cellular energetics. Future research should focus on long-term effects, combination therapies, and personalized medicine approaches to fully harness the potential of MTx in improving patient outcomes in PCAS.


Assuntos
Parada Cardíaca , Hipotermia Induzida , Traumatismo por Reperfusão , Animais , Humanos , Terapia Combinada , Medicina de Precisão , Parada Cardíaca/terapia , Imunomodulação , Traumatismo por Reperfusão/terapia
7.
J Tradit Chin Med ; 44(2): 345-352, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38504540

RESUMO

OBJECTIVE: To explore the effect of acupuncture treatment on cerebral ischaemia-reperfusion injury (CIRI) and reveal the underlying mechanism of the effect based on nuclear receptor coactivator 4 (NCOA4) mediated ferritinophagy. METHODS: Sprague-Dawley male rats were divided into four groups: the sham group, model group, acupuncture group, and sham acupuncture group. After 2 h of middle cerebral artery occlusion (MCAO), reperfusion was performed for 24 h to induce CIRI. The rats were treated with acupuncture at the Neiguan (PC6) and Shuigou (GV26) acupoints. Their neurological function was evaluated by taking their Bederson scores at 2 h after ischaemia and 24 h after reperfusion. Triphenyltetrazolium chloride staining was applied to assess the cerebral infarct volume at 24 h after reperfusion. The malondialdehyde (MDA) and ferrous iron (Fe2+) levels were observed after 24 h of reperfusion using an assay kit. Western blotting was performed to detect the expression of NCOA4 and ferritin heavy chain 1 (FTH1) at 24 h after reperfusion. Moreover, the colocalization of ferritin with neurons, NCOA4 with microtubule-associated protein 1 light chain 3 (LC3), and NCOA4 with ferritin was visualized using immunofluorescence staining. RESULTS: Acupuncture significantly improved neurological function and decreased cerebral infarct volume in the acupuncture group. Following CIRI, the expression of NCOA4, LC3 and FTH1 was increased, which enhanced ferritinophagy and induced an inappropriate accumulation of Fe2+ and MDA in the ischaemic brain. However, acupuncture dramatically downregulated the expression of NCOA4, LC3 and FTH1, inhibited the overactivation of ferritinophagy, and decreased the levels of MDA and Fe2+. CONCLUSIONS: Acupuncture can inhibit NCOA4-mediated ferritinophagy and protect neurons against CIRI in a rat model.


Assuntos
Terapia por Acupuntura , Isquemia Encefálica , Traumatismo por Reperfusão , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Isquemia Encefálica/metabolismo , Infarto Cerebral , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/terapia , Traumatismo por Reperfusão/metabolismo , Ferritinas/genética , Coativadores de Receptor Nuclear/metabolismo
8.
Zhen Ci Yan Jiu ; 49(3): 238-246, 2024 Mar 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38500320

RESUMO

OBJECTIVES: To observe the effect of moxibustion preconditioning on inflammatory response in rats with cerebral ischemia reperfusion injury (CIRI), so as to explore its mechanisms underlying improving CIRI. METHODS: Seventy-five male SD rats were randomly divided into sham operation, model, moxibustion preconditioning 3 days (Moxi 1), moxibustion preconditioning 5 days (Moxi 2) and moxibustion preconditioning 7 days (Moxi 3) groups, with 15 rats in each group. Moxibustion was applied at "Baihui"(GV20), "Dazhui"(GV14) and "Zusanli"(ST36) for 20 min once a day, totally for 3, 5 or 7 days. Thirty minutes after the last moxibustion treatment, the CIRI model was established by occlusion of the middle cerebral artery. The neurological deficit score was assessed by using Longa's method. The infarct size of the brain assessed after staining with 2% triphenyltetrazolium chloride (TTC). The morphological changes of cortical neurons were observed by HE staining. The contents of inflammatory factors interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), S-100ß protein (S-100ß) and neuron-specific enolase (NSE) were detected by ELISA. The expression of phosphatidylinositol-3-kinase (PI3K), p-PI3K, protein kinase B (AKT) and mammalian target of rapamycin (mTOR) proteins in the ischemic cortex tissues were detected by immunohistochemistry and Western blot. RESULTS: Compared with the sham operation group, the neurological function score and the percentage of cerebral ischemic volume were increased (P<0.01). The contents of serum IL-1ß, TNF-α, S-100ß and NSE were significantly increased (P<0.01), while the protein expressions of PI3K, p-PI3K, AKT and mTOR in the cerebral cortex were significantly decreased (P<0.01) in the model group. Compared with the model group, the neurological function score and the percentage of cerebral ischemic volume were significantly decreased (P<0.01). The contents of serum IL-1ß, TNF-α, S-100ß and NSE were significantly decreased (P<0.01), and the expressions of PI3K, p-PI3K, AKT and mTOR proteins in the cerebral cortex were significantly increased (P<0.01) in three moxibustion groups. Compared with the Moxi 1 and Moxi 2 groups, the above indicators were significantly improved in rats of the Moxi 3 group (P<0.01, P<0.05). CONCLUSIONS: Moxibustion preconditioning can significantly improve the neurological function of rats after ischemia-reperfusion, inhibit serum inflammatory factors IL-1 ß and TNF-α, inhibit brain tissue injury markers S-100ß and NSE, which may be related to the activation of PI3K/AKT/mTOR signaling pathway. The protective effect of moxibustion preconditioning for 7 days on CIRI was better than that of 5 days and 3 days.


Assuntos
Isquemia Encefálica , Moxibustão , Traumatismo por Reperfusão , Ratos , Masculino , Animais , Proteínas Proto-Oncogênicas c-akt/genética , Ratos Sprague-Dawley , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinase/farmacologia , Fator de Necrose Tumoral alfa/genética , Subunidade beta da Proteína Ligante de Cálcio S100/farmacologia , Transdução de Sinais , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/terapia , Serina-Treonina Quinases TOR/genética , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Infarto Cerebral , Mamíferos
9.
Zhen Ci Yan Jiu ; 49(3): 302-306, 2024 Mar 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38500328

RESUMO

Ischemic stroke is currently the most common type of stroke, and the key pathological link is cerebral ischemia-reperfusion injury (CIRI), while the key factor leading to apoptosis and necrosis of ischemic nerve cells is calcium overload. Current studies have confirmed that acupuncture therapy has a good modulating effect on calcium homeostasis and can reduce cerebral ischemia-reperfusion induced damage of neuronal cells by inhibiting calcium overload. After reviewing the relevant literature published in the past 15 years, we find that acupuncture plays a role in regulating the pathological mechanism of calcium overload after CIRI by inhibiting the opening of connexin 43 hemichannels, regulating the intracellular free calcium ion concentration, suppressing the expression of calmodulin, and blocking the function of L-type voltage-gated calcium channels, thereby inhibiting calcium overload, regulating calcium homeostasis and antagonizing neuronal damage resulted from cerebral ischemia-reperfusion, which may provide ideas for future research.


Assuntos
Terapia por Acupuntura , Acupuntura , Isquemia Encefálica , Traumatismo por Reperfusão , Humanos , Cálcio/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/terapia , Traumatismo por Reperfusão/metabolismo , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Isquemia Encefálica/metabolismo , Infarto Cerebral
10.
Mol Biol Rep ; 51(1): 377, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427114

RESUMO

BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) exerts neuroprotective effects early in cerebral ischemia/reperfusion (I/R) injury. Intermittent theta-brust stimulation (iTBS), a more time-efficient modality of rTMS, improves the efficiency without at least decreasing the efficacy of the therapy. iTBS elevates cortical excitability, and in recent years it has become increasingly common to apply iTBS to patients in the early post-IS period. However, little is known about the neuroprotective mechanisms of iTBS. Endoplasmic reticulum stress (ERS), and ferroptosis have been shown to be involved in the development of I/R injury. We aimed to investigate the potential regulatory mechanisms by which iTBS attenuates neurological injury after I/R in rats. METHODS: Rats were randomly divided into three groups: sham-operated group, MCAO/R group, and MCAO/R + iTBS group, and were stimulated with iTBS 36 h after undergoing middle cerebral artery occlusion (MCAO) or sham-operated. The expression of ERS, ferroptosis, and apoptosis-related markers was subsequently detected by western blot assays. We also investigated the mechanism by which iTBS attenuates nerve injury after ischemic reperfusion in rats by using the modified Neurological Severity Score (mNSS) and the balance beam test to measure nerve function. RESULTS: iTBS performed early in I/R injury attenuated the levels of ERS, ferroptosis, and apoptosis, and improved neurological function, including mNSS and balance beam experiments. It is suggested that this mode of stimulation reduces the cost per treatment by several times without compromising the efficacy of the treatment and could be a practical and less costly intervention.


Assuntos
Ferroptose , Traumatismo por Reperfusão , Humanos , Ratos , Animais , Estimulação Magnética Transcraniana , Traumatismo por Reperfusão/terapia , Reperfusão , Estresse do Retículo Endoplasmático
11.
Sci Rep ; 14(1): 6720, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509215

RESUMO

The incidence of acute kidney injury (AKI) due to ischemia-reperfusion (IR) injury is increasing. There is no effective treatment for AKI, and because of this clinical challenge, AKI often progresses to chronic kidney disease, which is closely associated with poor patient outcomes and high mortality rates. Small extracellular vesicles from human umbilical cord mesenchymal stem cells (hUCMSC-sEVs) play increasingly vital roles in protecting tissue function from the effects of various harmful stimuli owing to their specific biological features. In this study, we found that miR-100-5p was enriched in hUCMSC-sEVs, and miR-100-5p targeted FKBP5 and inhibited HK-2 cell apoptosis by activating the AKT pathway. HK-2 cells that were exposed to IR injury were cocultured with hUCMSC-sEVs, leading to an increase in miR-100-5p levels, a decrease in FKBP5 levels, and an increase in AKT phosphorylation at Ser 473 (AKT-473 phosphorylation). Notably, these effects were significantly reversed by transfecting hUCMSCs with an miR-100-5p inhibitor. Moreover, miR-100-5p targeted FKBP5, as confirmed by a dual luciferase reporter assay. In vivo, intravenous infusion of hUCMSC-sEVs into mice suffering from IR injury resulted in significant apoptosis inhibition, functional maintenance and renal histological protection, which in turn decreased FKBP5 expression levels. Overall, this study revealed an effect of hUCMSC-sEVs on inhibiting apoptosis; hUCMSC-sEVs reduced renal IR injury by delivering miR-100-5p to HK-2 cells, targeting FKBP5 and thereby promoting AKT-473 phosphorylation to activate the AKT pathway. This study provides novel insights into the role of hUCMSC-sEVs in the treatment of AKI.


Assuntos
Injúria Renal Aguda , Exossomos , Vesículas Extracelulares , Células-Tronco Mesenquimais , MicroRNAs , Traumatismo por Reperfusão , Humanos , Camundongos , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Exossomos/metabolismo , Injúria Renal Aguda/patologia , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/terapia , Traumatismo por Reperfusão/metabolismo , Vesículas Extracelulares/metabolismo , Células-Tronco Mesenquimais/metabolismo
12.
Diving Hyperb Med ; 54(1): 16-22, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38507906

RESUMO

Introduction: This study aimed to investigate whether hyperbaric oxygen treatment (HBOT) could ameliorate ischaemia-reperfusion injury in a rat model of ovarian torsion-detorsion. Methods: Twenty-seven rats were divided among four groups: surgical sham rats (S) (n = 6) underwent identical anaesthesia and surgical incisions to other groups (n = 7 per group) but with no ovary intervention; torsion rats (T) underwent laparotomy, ovarian torsion, relaparotomy and sacrifice after three hours; torsion and detorsion rats (T/DT) underwent laparotomy, ovarian torsion (three hours), relaparotomy and detorsion, and sacrifice after one week; torsion, detorsion, hyperbaric oxygen rats (T/DT/HBOT) underwent laparotomy, ovarian torsion, relaparotomy and detorsion, and sacrifice after one week during which HBOT was provided 21 times (100% oxygen at 600 kPa for 50 min). In all groups blood collection for markers of oxidative stress or related responses, and ovary collection for histology were performed after sacrifice. Results: When the T/DT, and T/DT/HBOT groups were compared, 8-hydroxy-2'-deoxyguanosine (a marker of oxidative damage to DNA) and malondialdehyde (a product of lipid peroxidation) levels were lower in the T/DT/HBOT group. Anti-Mullerian hormone levels were higher in the T/DT/HBOT group compared to the T/DT group. In addition, oedema, vascular occlusion, neutrophilic infiltration and follicular cell damage were less in the T/DT/HBOT group than in the T/DT group. Conclusions: When biochemical and histopathological findings were evaluated together, HBOT appeared reduce ovarian ischaemia / reperfusion injury in this rat model of ovarian torsion-detorsion.


Assuntos
Oxigenoterapia Hiperbárica , Traumatismo por Reperfusão , Humanos , Feminino , Ratos , Animais , Torção Ovariana/terapia , Ratos Wistar , Antioxidantes , Oxigênio , Traumatismo por Reperfusão/terapia
13.
Brain Behav ; 14(1): e3382, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38376040

RESUMO

BACKGROUND: This study aimed to investigate dynamic urinary proteome changes of electroacupuncture (EP) on cerebral ischemia-reperfusion (CI/R) injured rats and to explore the therapeutic biological mechanisms of EP. METHODS: First, changed urinary proteins were found in EP stimulation in healthy rats. Then, we used a CI/R injury rat model induced by Pulsinelli's four-vessel occlusion (4-VO) method to explore the function of EP on urinary proteome in CI/R injury. Urine samples were collected for proteome analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and bioinformatics analysis. RESULTS: In total, 384 proteins were identified, among which 47 proteins (23 upregulated, 24 downregulated) were differentially expressed with 0.6-log FC and p < .05. Gene ontology analysis revealed that the cell redox homeostasis, acute-phase response, response to lipopolysaccharide, and cellular response to glucocorticoid stimulus were significantly enriched. The partially biologically connected differential proteins were found by the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis in the EP group. With the CI/R rat model, 80 proteins (27 upregulated, 53 downregulated) were significantly changed in the CI/R rats compared to the controls. Among these differentially expressed proteins (DEPs), 23 proteins (17 upregulated, six downregulated) showed significant changes after EP treatment (0.6-log FC change, p < .05). The main related biological processes were aging, immune response, acute-phase response, liver regeneration, protein catabolic process, and response to oxidative stress. Many metabolic pathways were enriched by KEGG analysis. CONCLUSION: Our results indicate that the EP could alleviate cerebral damage induced by ischemia-reperfusion through an anti-inflammatory and metabolism regulation mechanism. The urinary proteome might reflect the pathophysiological changes in EP pretreatment in the treatment and prevention of CI/R injury.


Assuntos
Isquemia Encefálica , Eletroacupuntura , Traumatismo por Reperfusão , Ratos , Animais , Ratos Sprague-Dawley , Proteoma/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem , Isquemia Encefálica/genética , Infarto Cerebral , Traumatismo por Reperfusão/terapia , Traumatismo por Reperfusão/metabolismo
14.
Zhen Ci Yan Jiu ; 49(2): 127-134, 2024 Feb 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38413033

RESUMO

OBJECTIVES: To investigate the neuroprotective effect of electroacupuncture (EA) at "Quchi"(LI11) and "Zusanli"(ST36) in the rats with cerebral ischemia reperfusion injury and its influence on programmed necrosis of cerebral cortical neurons. METHODS: Sixty male SD rats were randomly divided into sham-operation group, model group, EA group and inhibitor group, with 15 rats in each group. Left middle cerebral artery occlusion model was established using the modified thread embolism method. In the sham-operation group, the carotid artery was exposed and dissociated in each rat. EA was applied to "Quchi"(LI11) and "Zusanli"(ST36) on the right side for 30 min each time, once daily for 7 days in the rats of the EA group. The rats in the inhibitor group were intraperitoneally injected with norstatin-1 (0.6 mg/kg) for consecutive 7 days. The neurological deficit score of rats in each group was observed. HE staining was adopted to detect the degree of pathological damage of the cerebral cortex in the infarction area. Using TUNEL staining, the apoptosis of cortical neurons in the infarction area was determined;the contents of tumor necrosis factor α (TNF-α), interleukin (IL)-1ß and IL-6 were detected by ELISA;the mRNA and protein expression of the receptor interacting protein-1 (RIP1), the receptor interacting protein-3 (RIP3) and the substrate mixed lineage kinase like protein (MLKL) were detected by fluorescence quantitative PCR and Western blot, respectively. RESULTS: In comparison with the sham-operation group, the neurological deficit score in the model group was higher(P<0.01);HE staining showed that there was the pathological damage in the infarction area;the neuron apoptosis rate, the contents of TNF-α, IL-1ß and IL-6, and the mRNA and protein expressions of RIP1, RIP3 and MLKL increased(P<0.01) in the model group. In the EA group, the neurological deficit score was reduced(P<0.01);HE staining showed that the pathological damage was ameliorated in the infarction area;the neuron apoptosis rate, the contents of TNF-α, IL-1ß and IL-6, and the mRNA and protein expressions of RIP1, RIP3, MLKL decreased(P<0.05, P<0.01) when compared with those in the model group. CONCLUSIONS: EA can attenuate cerebral ischemia reperfusion injury and display its neuroprotective effect probably through inhibiting programmed necrosis of cerebral cortical neurons in the rats.


Assuntos
Isquemia Encefálica , Eletroacupuntura , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/genética , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Interleucina-6 , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/terapia , Neurônios/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Necrose , Apoptose , Infarto , RNA Mensageiro , Proteínas Quinases
15.
Shock ; 61(5): 650-659, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38113056

RESUMO

ABSTRACT: Ischemia can cause reversible or irreversible cell or tissue damage, and reperfusion after ischemia not only has no therapeutic effect but also aggravates cell damage. Notably, gut tissue is highly susceptible to ischemia-reperfusion (IR) injury under many adverse health conditions. Intestinal IR (IIR) is an important pathophysiological process in critical clinical diseases. Therefore, it is necessary to identify better therapeutic methods for relieving intestinal ischemia and hypoxia. Hyperbaric oxygenation refers to the intermittent inhalation of 100% oxygen in an environment greater than 1 atm pressure, which can better increase the oxygen level in the tissue and change the inflammatory pathway. Currently, it can have a positive effect on hypoxia and ischemic diseases. Related studies have suggested that hyperbaric oxygen can significantly reduce ischemia-hypoxic injury to the brain, spinal cord, kidney, and myocardium. This article reviews the pathogenesis of IR and the current treatment measures, and further points out that hyperbaric oxygen has a better effect in IR. We found that not only improved hypoxia but also regulated IR induced injury in a certain way. From the perspective of clinical application, these changes and the application of hyperbaric oxygen therapy have important implications for treatment, especially IIR.


Assuntos
Oxigenoterapia Hiperbárica , Intestinos , Traumatismo por Reperfusão , Oxigenoterapia Hiperbárica/métodos , Traumatismo por Reperfusão/terapia , Humanos , Intestinos/irrigação sanguínea , Animais
16.
Acupunct Med ; 42(1): 23-31, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38126262

RESUMO

BACKGROUND: This study aimed to investigate the effects of electroacupuncture (EA) on cognitive recovery and synaptic remodeling in a rat model of middle cerebral artery occlusion (MCAO) followed by reperfusion and explore the possible mechanism. METHOD: Focal cerebral ischemia was modeled in healthy adult Sprague-Dawley rats by MCAO. The MCAO rats were classified into four groups: sham, MCAO, MCAO + GB20 (receiving EA at GB20) and MCAO + NA (receiving EA at a "non-acupoint" location not corresponding to any traditional acupuncture point location about 10 mm above the iliac crest). Neurological deficit scores and behavior were assessed before and during the treatment. After intervention for 7 days, the hippocampus was dissected to analyze growth-associated protein (GAP)-43, synaptophysin (SYN) and postsynaptic density protein (PSD)-95 expression levels by Western blotting. Bioinformatic analysis and primary hippocampal neurons with calcium-voltage gated channel subunit alpha 1B (CACNA1B) gene overexpression were used to screen the target genes for EA against MCAO. RESULTS: Significant amelioration of neurological deficits and learning/memory were found in MCAO + GB20 rats compared with MCAO or MCAO + NA rats. Protein levels of GAP-43, SYN and PSD-95 were significantly improved in MCAO + GB20-treated rats together with an increase in the number of synapses in the hippocampal CA1 region. CACNA1B appeared to be a target gene of EA in MCAO. There were increased mRNA levels of CACNA1B, calmodulin (CaM), Ca2+/calmodulin-dependent protein kinase type II (CaMKII) and cyclic adenosine monophosphate response element binding (CREB) and increased phosphorylation of CaM, CaMKII and CREB in the hippocampal region in MCAO + GB20 versus MCAO and MCAO + NA groups. CACNA1B overexpression modulated expression of the CaM-CaMKII-CREB axis. CONCLUSION: EA treatment at GB20 may ameliorate the negative effects of MCAO on cognitive function in rats by enhancing synaptic plasticity. EA treatment at GB20 may exert this neuroprotective effect by regulating the CACNA1B-CaM-CaMKII-CREB axis.


Assuntos
Isquemia Encefálica , Eletroacupuntura , Traumatismo por Reperfusão , Ratos , Animais , Ratos Sprague-Dawley , Calmodulina/metabolismo , Calmodulina/farmacologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/farmacologia , Cognição , Transdução de Sinais , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Isquemia Encefálica/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/terapia , Plasticidade Neuronal
17.
BMC Neurosci ; 24(1): 63, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057703

RESUMO

BACKGROUND: Ischemic stroke is a serious disease leading to significant disability in humans worldwide. Increasing evidence suggests that some microRNAs (miRNAs) participate in the pathophysiology of ischemic stroke. A key role for MiR-212 has been found in neuronal function and synaptic plasticity. Ischemic stroke can be effectively treated with electroacupuncture (EA); however, there is a lack of understanding of the relevant mechanisms. In this study, we employed behavioral test and resting-state functional magnetic resonance imaging (rs-fMRI) to detect behavioral and brain function alterations in rats suffering from ischemic stroke. The efficacy of EA therapy and miR-212-5p's role in this process were also evaluated. METHODS AND RESULTS: Forty rats were randomly divided into the following groups: Sham, middle cerebral artery occlusion/reperfusion (MCAO/R), MCAO/R + EA, MCAO/R + EA + antagomir-negative control and MCAO/R + EA + antagomir-212-5p groups. Behavioral changes were assessed by Catwalk gait analysis prior to and after modeling. Rs-fMRI was performed at one week after EA treatment, amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo) were calculated to reveal neural activity. Furthermore, neuronal apoptosis in the ischemic penumbra was analyzed using a TUNEL assay. Treatment with EA significantly improved the performance of rats in the behavioral test. The motor and cognition-related brain regions showed decreased ALFF and ReHo following focal cerebral ischemia-reperfusion, and EA treatment could reactivate these brain regions. Moreover, EA treatment significantly decreased MCAO/R-induced cell death. However, the transfection of antagomir-212-5p attenuated the therapeutic effect of EA. CONCLUSIONS: In conclusion, the results suggested that EA improved the behavioral and imaging outcomes of ischemic stroke through miR-212-5p.


Assuntos
Isquemia Encefálica , Eletroacupuntura , AVC Isquêmico , MicroRNAs , Traumatismo por Reperfusão , Acidente Vascular Cerebral , Humanos , Ratos , Animais , Ratos Sprague-Dawley , Eletroacupuntura/métodos , Antagomirs , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/terapia , Isquemia Encefálica/metabolismo , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Infarto da Artéria Cerebral Média/terapia , MicroRNAs/metabolismo , Traumatismo por Reperfusão/terapia , Traumatismo por Reperfusão/metabolismo , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/metabolismo
18.
Zhen Ci Yan Jiu ; 48(12): 1193-1201, 2023 Dec 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38146241

RESUMO

OBJECTIVES: To explore the mechanisms of acupuncture against cerebral ischemia/reperfusion injury (CIRI) through observing the expression of circular RNA HDAC2 (circHDAC2) in the hippocampus of rats. METHODS: SD rats were randomly divided into sham-operation, model and acupuncture groups, with 13 rats in each group. The rat model of CIRI was established by middle cerebral artery occlusion. In the acupuncture group, acupuncture was delivvered at "Dazhui" (GV14), "Shuigou" (GV26) and "Baihui" (GV20), and the needles were retained for 30 min each time and acupuncture was conducted once every 12 h for a total of 7 sessions. Before and after intervention, using modified Garcia scale, the neurological function of the rats were evaluated, and TTC staining was employed to determine the cerebral infarct area. Gene chip technology was used to screen the circRNAs with differential expressions in the ischemic hippocampus, and the circRNAs with co-differential expression (co-DE circRNAs) in the model group/sham-operation group, and the acupuncture group/model group separately. Among those circRNAs, the core circRNAs were screened according to P value, fold change (FC) and gene ontology (GO) analysis;and their expressions in the ischemic hippocampus were determined using quantitative real-time PCR (qPCR). Based on the verification results, a competing endogenous RNA (ceRNA) prediction network was constructed. The expression levels of microRNA (miRNA) and mRNA with high node centrality in the prediction network were validated by qPCR. RESULTS: Before intervention, compared with the sham-operation group, the modified Garcia score of each modeling group decreased (P<0.01). After intervention, the modified Garcia score was reduced and the cerebral infarct area ratio increased (P<0.01) in the model group when compared with the sham-operation group. In the acupuncture group, the modified Garcia score was higher and the cerebral infarct area ratio lower (P<0.01) than those of the model group. The microarray results of gene chip showed that 16 co-DE circRNAs were down-regulated in the model group and up-regulated in the acupuncture group, and 7 co-DE circRNAs up-regulated in the model group and down-regulated in the acupuncture group. The core circHDAC2 and circNTRK2 were screened according to P value, FC and the enrichment number of GO entries. QPCR results showed that, compared with the sham-operation group, the expression of circHDAC2 and circNTRK2 of the ischemic hippocampal tissue was down-regulated in the model group (P<0.01);and that of circHDAC2 and circNTRK2 up-regulated in the acupuncture group when compared with the model group (P<0.01). The relevant ceRNA regulatory network was constructed for circHDAC2 and the prediction results showed that the regulatory networks contained 12 miRNAs and 31 mRNAs. Results of verifying miRNA with high network node centrality and mRNA relevant with nerve regulation showed that, when compared with the sham-operation group, the expression levels of miR-29a, miR-29b and the solute carrier family 30 member 3 (SLC30A3) mRNA in the ischemic hippocampus were down-regulated (P<0.01);and those of miR-3065 and mercaptopyruvate sulfurtransferase (MPST) up-regulated (P<0.01) in the model group. Compared with the model group, the expressions of miR-29a, miR-29b and SLC30A3 mRNA in the ischemic hippocampus were up-regulated (P<0.01, P<0.05), while that of miR-3065 down-regulated (P<0.05) in the acupuncture group. CONCLUSIONS: Acupuncture significantly improves the neurological function and reduces the cerebral infarct area in CIRI rats, which may be related to the regulation of hippocampal circHDAC2/miR-3065/SLC30A3 axis.


Assuntos
Terapia por Acupuntura , Isquemia Encefálica , MicroRNAs , Traumatismo por Reperfusão , Ratos , Animais , RNA Circular/genética , Ratos Sprague-Dawley , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Hipocampo/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , MicroRNAs/genética , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/terapia , RNA Mensageiro
19.
Zhen Ci Yan Jiu ; 48(12): 1282-1288, 2023 Dec 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38146252

RESUMO

In clinical practice, operative stress varies from surgeries, which may lead to many injuries such as ischemia-reperfusion injury (IRI), hyperactivation of sympathetic nervous system (SNS), post-traumatic immunosuppression (PTI), hypercoagulation and inflammation. Acupuncture is effective and advantageous in regulating the stress response to surgery. The great progress has been made in recent years of acupuncture research in postoperative visceral IRI, SNS hyperactivation, PTI, hypercoagulation and inflammation. By collecting the relevant evidences of acupuncture in this field, the application value of acupuncture involved in modulating surgical stress response and the progress of mechanism research are explored and summarized.


Assuntos
Terapia por Acupuntura , Traumatismo por Reperfusão , Humanos , Traumatismo por Reperfusão/terapia , Inflamação
20.
Zhen Ci Yan Jiu ; 48(11): 1088-1094, 2023 Nov 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37984905

RESUMO

OBJECTIVES: To investigate the mechanism of electroacupuncture (EA) in alleviating cerebral ische-mia injury by activating the Yap-OPA1 signaling axis. METHODS: A total of 48 male SD rats were used in the present study. The focal CIRI model was established by occlusion of the middle cerebral artery and reperfusion (MCAO/R), followed by dividing the CIRI rats into model group, EA group and EA+Ver (Verteporfin, Yap antagonist) group (n=12 in each group). And another 12 normal rats were used as the sham operation group. For rats of the EA group, EA (4 Hz/20 Hz, 0.5 mA) was applied to "Baihui"(GV20) and "Shenting"(GV24) for 20 min, once daily for 7 days. The neurological deficit score (0 to 4 points) was given according to Longa's method. The infarct volume of rats in each group was assessed by TTC method, and the expression levels of Yes associated protein (Yap), Optic atrophy protein 1 (OPA1), mitofusin 1 (Mfn1), mitofusin 2 (Mfn2) proteins and mRNAs in cerebral cortex of infarcted side, as well as Bax (proapoptotic factor) and Bcl-1 (anti-apoptotic protein) proteins were detected by Westernblot, and real-time PCR, and the immunoactivity of Yap and OPA1 was detected by immunofluorescent staining. RESULTS: After modeling, the infarct volume, neurological deficit score and the expression of Bax were significantly increased (P<0.01), while the mRNA and protein expressions of Yap, OPA1, Mfn2, Mfn1, and Bcl-2 were significantly down-regulated in the model group relevant to the sham operation group (P<0.01, P<0.05). Compared with the model group, the neurological deficit score, infarct volume and the expression of Bax were significantly decreased (P<0.01), while the expression levels of Yap, OPA1, Mfn2, Mfn1 proteins and mRNAs and Bcl-2 protein, Yap and OPA1 immunofluorescence intensify were considerably up-regulated in the EA group (P<0.01, P<0.05). Following administration of Ver, the effects of EA in down-regulating the neurological score, infarct volume, and Bax expression and up-regulating the expressions of Yap, OPA1, Mfn1, Mfn2 proteins and mRNAs and Yap and OPA1 immunofluorescence intensify were eliminated. CONCLUSIONS: EA of GV20 and GV24 can improve the neurological function in rats with CIRI, which may be associated with its functions in activating mitochondrial fusion function and up-regulating Yap-OPA1 signaling axis.


Assuntos
Isquemia Encefálica , Eletroacupuntura , Traumatismo por Reperfusão , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Dinâmica Mitocondrial , Proteína X Associada a bcl-2 , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/terapia , Infarto
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