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1.
Trials ; 22(1): 595, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34488845

RESUMO

BACKGROUND: Chronic lower limb ischemia develops earlier and more frequently in patients with type 2 diabetes mellitus. Diabetes remains the main cause of lower-extremity non-traumatic amputations. Current medical treatment, based on antiplatelet therapy and statins, has demonstrated deficient improvement of the disease. In recent years, research has shown that it is possible to improve tissue perfusion through therapeutic angiogenesis. Both in animal models and humans, it has been shown that cell therapy can induce therapeutic angiogenesis, making mesenchymal stromal cell-based therapy one of the most promising therapeutic alternatives. The aim of this study is to evaluate the feasibility, safety, and efficacy of cell therapy based on mesenchymal stromal cells derived from adipose tissue intramuscular administration to patients with type 2 diabetes mellitus with critical limb ischemia and without possibility of revascularization. METHODS: A multicenter, randomized double-blind, placebo-controlled trial has been designed. Ninety eligible patients will be randomly assigned at a ratio 1:1:1 to one of the following: control group (n = 30), low-cell dose treatment group (n = 30), and high-cell dose treatment group (n = 30). Treatment will be administered in a single-dose way and patients will be followed for 12 months. Primary outcome (safety) will be evaluated by measuring the rate of adverse events within the study period. Secondary outcomes (efficacy) will be measured by assessing clinical, analytical, and imaging-test parameters. Tertiary outcome (quality of life) will be evaluated with SF-12 and VascuQol-6 scales. DISCUSSION: Chronic lower limb ischemia has limited therapeutic options and constitutes a public health problem in both developed and underdeveloped countries. Given that the current treatment is not established in daily clinical practice, it is essential to provide evidence-based data that allow taking a step forward in its clinical development. Also, the multidisciplinary coordination exercise needed to develop this clinical trial protocol will undoubtfully be useful to conduct academic clinical trials in the field of cell therapy in the near future. TRIAL REGISTRATION: ClinicalTrials.gov NCT04466007 . Registered on January 07, 2020. All items from the World Health Organization Trial Registration Data Set are included within the body of the protocol.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 2 , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Mesenquimais , Noma , Tecido Adiposo , Animais , Ensaios Clínicos Fase II como Assunto , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/terapia , Método Duplo-Cego , Humanos , Isquemia/diagnóstico , Isquemia/terapia , Estudos Multicêntricos como Assunto , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2 , Resultado do Tratamento
2.
EClinicalMedicine ; 25: 100454, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32838232

RESUMO

Background: Identification of effective treatments in severe cases of COVID-19 requiring mechanical ventilation represents an unmet medical need. Our aim was to determine whether the administration of adipose-tissue derived mesenchymal stromal cells (AT-MSC) is safe and potentially useful in these patients. Methods: Thirteen COVID-19 adult patients under invasive mechanical ventilation who had received previous antiviral and/or anti-inflammatory treatments (including steroids, lopinavir/ritonavir, hydroxychloroquine and/or tocilizumab, among others) were treated with allogeneic AT-MSC. Ten patients received two doses, with the second dose administered a median of 3 days (interquartile range-IQR- 1 day) after the first one. Two patients received a single dose and another patient received 3 doses. Median number of cells per dose was 0.98 × 106 (IQR 0.50 × 106) AT-MSC/kg of recipient's body weight. Potential adverse effects related to cell infusion and clinical outcome were assessed. Additional parameters analyzed included changes in imaging, analytical and inflammatory parameters. Findings: First dose of AT-MSC was administered at a median of 7 days (IQR 12 days) after mechanical ventilation. No adverse events were related to cell therapy. With a median follow-up of 16 days (IQR 9 days) after the first dose, clinical improvement was observed in nine patients (70%). Seven patients were extubated and discharged from ICU while four patients remained intubated (two with an improvement in their ventilatory and radiological parameters and two in stable condition). Two patients died (one due to massive gastrointestinal bleeding unrelated to MSC therapy). Treatment with AT-MSC was followed by a decrease in inflammatory parameters (reduction in C-reactive protein, IL-6, ferritin, LDH and d-dimer) as well as an increase in lymphocytes, particularly in those patients with clinical improvement. Interpretation: Treatment with intravenous administration of AT-MSC in 13 severe COVID-19 pneumonia under mechanical ventilation in a small case series did not induce significant adverse events and was followed by clinical and biological improvement in most subjects. Funding: None.

3.
Front Immunol ; 11: 609961, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33633730

RESUMO

Snakebite envenoming is a global neglected disease with an incidence of up to 2.7 million new cases every year. Although antivenoms are so-far the most effective treatment to reverse the acute systemic effects induced by snakebite envenoming, they have a limited therapeutic potential, being unable to completely neutralize the local venom effects. Local damage, such as dermonecrosis and myonecrosis, can lead to permanent sequelae with physical, social, and psychological implications. The strong inflammatory process induced by snake venoms is associated with poor tissue regeneration, in particular the lack of or reduced skeletal muscle regeneration. Mesenchymal stromal cells (MSCs)-based therapies have shown both anti-inflammatory and pro-regenerative properties. We postulate that using allogeneic MSCs or their cell-free products can induce skeletal muscle regeneration in snakebite victims, improving all the three steps of the skeletal muscle regeneration process, mainly by anti-inflammatory activity, paracrine effects, neovascularization induction, and inhibition of tissue damage, instrumental for microenvironment remodeling and regeneration. Since snakebite envenoming occurs mainly in areas with poor healthcare, we enlist the principles and potential of MSCs-based therapies and discuss regulatory issues, good manufacturing practices, transportation, storage, and related-procedures that could allow the administration of these therapies, looking forward to a safe and cost-effective treatment for a so far unsolved and neglected health problem.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Desenvolvimento Muscular , Músculo Esquelético/fisiopatologia , Regeneração , Mordeduras de Serpentes/cirurgia , Animais , Humanos , Mediadores da Inflamação/metabolismo , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Necrose , Fenótipo , Transdução de Sinais , Mordeduras de Serpentes/diagnóstico , Mordeduras de Serpentes/metabolismo , Mordeduras de Serpentes/fisiopatologia , Resultado do Tratamento
4.
Am J Physiol Endocrinol Metab ; 284(5): E980-7, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12517739

RESUMO

Pancreatic beta-cells constitute a well-communicating multicellular network that permits a coordinated and synchronized signal transmission within the islet of Langerhans that is necessary for proper insulin release. Gap junctions are the molecular keys that mediate functional cellular connections, which are responsible for electrical and metabolic coupling in the majority of cell types. Although the role of gap junctions in beta-cell electrical coupling is well documented, metabolic communication is still a matter of discussion. Here, we have addressed this issue by use of a fluorescence recovery after photobleaching (FRAP) approach. This technique has been validated as a reliable and noninvasive approach to monitor functional gap junctions in real time. We show that control pancreatic islet cells did not exchange a gap junction-permeant molecule in either clustered cells or intact islets of Langerhans under conditions that allowed cell-to-cell exchange of current-carrying ions. Conversely, we have detected that the same probe was extensively transferred between islet cells of transgenic mice expressing connexin 32 (Cx32) that have enhanced junctional coupling properties. The results indicate that the electrical coupling of native islet cells is more extensive than dye communication. Dye-coupling domains in islet cells appear more restricted than previously inferred with other methods.


Assuntos
Junções Comunicantes/fisiologia , Ilhotas Pancreáticas/fisiologia , Animais , Astrócitos/fisiologia , Comunicação Celular/fisiologia , Células Cultivadas , Conexinas/metabolismo , Processamento Eletrônico de Dados , Eletrofisiologia , Fluoresceínas , Fluorescência , Ilhotas Pancreáticas/citologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fotodegradação
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