RESUMO
Pulmonary fibrosis, a debilitating lung disorder characterised by excessive fibrous tissue accumulation in lung parenchyma, compromises respiratory function leading to a life-threatening respiratory failure. While its origins are multifaceted and poorly understood, the urokinase system, including urokinase-type plasminogen activator (uPA) and its receptor (uPAR), plays a significant role in regulating fibrotic response, extracellular matrix remodelling, and tissue repair. Mesenchymal stem/stromal cells (MSCs) hold promise in regenerative medicine for treating pulmonary fibrosis. Our study aimed to investigate the potential of MSCs to inhibit pulmonary fibrosis as well as the contribution of uPAR expression to this effect. We found that intravenous MSC administration significantly reduced lung fibrosis in the bleomycin-induced pulmonary fibrosis model in mice as revealed by MRI and histological evaluations. Notably, administering the MSCs isolated from adipose tissue of uPAR knockout mice (Plaur-/- MSCs) attenuated lung fibrosis to a lesser extent as compared to WT MSCs. Collagen deposition, a hallmark of fibrosis, was markedly reduced in lungs treated with WT MSCs versus Plaur-/- MSCs. Along with that, endogenous uPA levels were affected differently; after Plaur-/- MSCs were administered, the uPA content was specifically decreased within the blood vessels. Our findings support the potential of MSC treatment in attenuating pulmonary fibrosis. We provide evidence that the observed anti-fibrotic effect depends on uPAR expression in MSCs, suggesting that uPAR might counteract the uPA accumulation in lungs.
Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Fibrose Pulmonar , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Animais , Masculino , Camundongos , Bleomicina , Modelos Animais de Doenças , Pulmão/patologia , Pulmão/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fibrose Pulmonar/terapia , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase/genética , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/genéticaRESUMO
Introduction: Impaired function of brain morphogenic genes is considered one of the predisposing factors for the manifestation of psychiatric and cognitive disorders, such as paranoid schizophrenia (SCZ) and major depressive disorder (MDD). Identification of such genes (genes of neurotrophic factors and guidance molecules among them) and their deleterious genetic variants serves as a key to diagnosis, prevention, and possibly treatment of such disorders. In this study, we have examined the prevalence of genomic variants in brain morphogenic genes in individuals with SCZ and MDD within a Russian population. Methods: We have performed whole-exome sequencing of 21 DNA samples: 11 from individuals with SCZ and 10 with MDD, followed by ARMS (Amplification-Refractory Mutation System) based screening of detected single nucleotide variants (SNVs) in larger groups: 102 for individuals with SCZ, 79 for those with MDD and 103 for healthy donors. Results: Whole-exome sequencing has revealed 226 missense mutations in 79 genes (out of 140 studied), some of which occur in patients with psychiatric disorders significantly more frequently than in healthy donors. We have identified previously undescribed genomic variants in brain morphogenic genes: CDH2 (rs1944294-T and rs17445840-T), DCHS2 (rs11935573-G and rs12500437-G/T) and CDH23 (rs1227051-G/A), significantly associated with the incidence of SCZ and MDD in the Russian population. For some SNVs (rs6265-T, rs1944294-T, rs11935573-G, rs4760-G) sex-biased differences in their prevalence between SCZ/MDD patients and healthy donors was detected. Discussion: However, the functional significance of the SNVs identified has still to be confirmed in cellular and animal models. Once it is fulfilled, these SNVs have the potential to complement the diagnostic toolbox for assessing susceptibility to mental disorders. The data obtained indirectly confirm the importance of adequate brain structure formation for its correct functioning and preservation of mental health.
RESUMO
Mental illness and cognitive disorders represent a serious problem for the modern society. Many studies indicate that mental disorders are polygenic and that impaired brain development may lay the ground for their manifestation. Neural tissue development is a complex and multistage process that involves a large number of distant and contact molecules. In this review, we have considered the key steps of brain morphogenesis, and the major molecule families involved in these process. The review provides many indications of the important contribution of the brain development process and correct functioning of certain genes to human mental health. To our knowledge, this comprehensive review is one of the first in this field. We suppose that this review may be useful to novice researchers and clinicians wishing to navigate the field.
RESUMO
The severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) and the Ñoronavirus disease 2019 (COVID-19) have become a global health threat. At the height of the pandemic, major efforts were focused on reducing COVID-19-associated morbidity and mortality. Now is the time to study the long-term effects of the pandemic, particularly cognitive impairment associated with long COVID. In recent years much attention has been paid to the possible relationship between COVID-19 and Alzheimer's disease, which is considered a main cause of age-related cognitive impairment. Genetic predisposition was shown for both COVID-19 and Alzheimer's disease. However, the analysis of the similarity of the genetic architecture of these diseases is usually limited to indicating a positive genetic correlation between them. In this review, we have described intrinsic linkages between COVID-19 and Alzheimer's disease, pointed out shared susceptibility genes that were previously identified in genome-wide association studies of both COVID-19 and Alzheimer's disease, and highlighted a panel of SNPs that includes candidate genetic risk markers of the long COVID-associated cognitive impairment.
RESUMO
T-cadherin is a regulator of blood vessel remodeling and angiogenesis, involved in adiponectin-mediated protective effects in the cardiovascular system and in skeletal muscles. GWAS study has previously demonstrated a SNP in the Cdh13 gene to be associated with hypertension. However, the role of T-cadherin in regulating blood pressure has not been experimentally elucidated. Herein, we generated Cdh13∆Exon3 mice lacking exon 3 in the Cdh13 gene and described their phenotype. Cdh13∆Exon3 mice exhibited normal gross morphology, life expectancy, and breeding capacity. Meanwhile, their body weight was considerably lower than of WT mice. When running on a treadmill, the time spent running and the distance covered by Cdh13∆Exon3 mice was similar to that of WT. The resting blood pressure in Cdh13∆Exon3 mice was slightly higher than in WT, however, upon intensive physical training their systolic blood pressure was significantly elevated. While adiponectin content in the myocardium of Cdh13∆Exon3 and WT mice was within the same range, adiponectin plasma level was 4.37-fold higher in Cdh13∆Exon3 mice. Moreover, intensive physical training augmented the AMPK phosphorylation in the skeletal muscles and myocardium of Cdh13∆Exon3 mice as compared to WT. Our data highlight a critically important role of T-cadherin in regulation of blood pressure and stamina in mice, and may shed light on the pathogenesis of hypertension.
Assuntos
Adiponectina , Hipertensão , Animais , Camundongos , Pressão Sanguínea , Adiponectina/genética , Caderinas/genética , Hipertensão/genéticaRESUMO
Cervical cancer ranks third among all new cancer cases and causes of cancer deaths in females. The paper provides an overview of cervical cancer prevention strategies employed in different regions, with incidence and mortality rates ranging from high to low. It assesses the effectiveness of approaches proposed by national healthcare systems by analysing data published in the National Library of Medicine (Pubmed) since 2018 featuring the following keywords: "cervical cancer prevention", "cervical cancer screening", "barriers to cervical cancer prevention", "premalignant cervical lesions" and "current strategies". WHO's 90-70-90 global strategy for cervical cancer prevention and early screening has proven effective in different countries in both mathematical models and clinical practice. The data analysis carried out within this study identified promising approaches to cervical cancer screening and prevention, which can further enhance the effectiveness of the existing WHO strategy and national healthcare systems. One such approach is the application of AI technologies for detecting precancerous cervical lesions and choosing treatment strategies. As such studies show, the use of AI can not only increase detection accuracy but also ease the burden on primary care.
RESUMO
Pulmonary fibrosis is a common and threatening post-COVID-19 complication with poorly resolved molecular mechanisms and no established treatment. The plasminogen activator system, including urokinase (uPA) and urokinase receptor (uPAR), is involved in the pathogenesis of COVID-19 and contributes to the development of lung injury and post-COVID-19 pulmonary fibrosis, although their cellular and molecular underpinnings still remain obscure. The aim of the current study was to assess the role of uPA and uPAR in the pathogenesis of pulmonary fibrosis. We analyzed uPA and uPAR expression in human lung tissues from COVID-19 patients with pulmonary fibrosis using single-cell RNA-seq and immunohistochemistry. We modeled lung fibrosis in Plau-/- and Plaur-/- mice upon bleomycin instillation and explored the effect of uPAR downregulation in A549 and BEAS-2B lung epithelial cells. We found that uPAR expression drastically decreased in the epithelial airway basal cells and monocyte/macrophage cells, whereas uPA accumulation significantly increased in tissue samples of COVID-19 patients. Lung injury and fibrosis in Plaur-/- vs. WT mice upon bleomycin instillation revealed that uPAR deficiency resulted in pro-fibrogenic uPA accumulation, IL-6 and ACE2 upregulation in lung tissues and was associated with severe fibrosis, weight loss and poor survival. uPAR downregulation in A549 and BEAS-2B was linked to an increased N-cadherin expression, indicating the onset of epithelial-mesenchymal transition and potentially contributing to pulmonary fibrosis. Here for the first time, we demonstrate that plasminogen treatment reversed lung fibrosis in Plaur-/- mice: the intravenous injection of 1 mg of plasminogen on the 21st day of bleomycin-induced fibrosis resulted in a more than a two-fold decrease in the area of lung fibrosis as compared to non-treated mice as evaluated by the 42nd day. The expression and function of the plasminogen activator system are dysregulated upon COVID-19 infection, leading to excessive pulmonary fibrosis and worsening the prognosis. The potential of plasminogen as a life-saving treatment for non-resolving post-COVID-19 pulmonary fibrosis warrants further investigation.
Assuntos
COVID-19 , Lesão Pulmonar , Fibrose Pulmonar , Humanos , Camundongos , Animais , Fibrose Pulmonar/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/genética , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/metabolismo , COVID-19/complicações , Fibrose , Plasminogênio , Bleomicina/toxicidadeRESUMO
Uncovering the risk factors for acute respiratory disease coronavirus 2019 (COVID-19) severity may help to provide a valuable tool for early patient stratification and proper treatment implementation, improving the patient outcome and lowering the burden on the healthcare system. Here we report the results of a single-center retrospective cohort study on 151 severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-infected symptomatic hospitalized adult patients. We assessed the association of several blood test measurements, soluble urokinase receptor (uPAR) serum level and specific single nucleotide polymorphisms of ACE (I/D), NOS3 (rs2070744, rs1799983), SERPINE1 (rs1799768), PLAU (rs2227564) and PLAUR (rs344781, rs2302524) genes, with the disease severity classified by the percentage of lung involvement on computerized tomography scans. Our findings reveal that the T/C genotype of PLAUR rs2302524 was independently associated with a less severe lung damage (odds ratio 0.258 [0.071-0.811]). Along with high C-reactive protein, fibrinogen and soluble uPAR serum levels turned out to be independently associated with more severe lung damage in COVID-19 patients. The identified factors may be further employed as predictors of a possibly severe COVID-19 clinical course.
Assuntos
COVID-19 , Pulmão , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Adulto , Humanos , COVID-19/genética , Genótipo , Pulmão/patologia , Receptores de Ativador de Plasminogênio Tipo Uroquinase/sangue , Receptores de Ativador de Plasminogênio Tipo Uroquinase/genética , Estudos Retrospectivos , SARS-CoV-2RESUMO
Urokinase receptor (uPAR) is a glycosylphosphatidylinositol (GPI)-anchored receptor of urokinase (uPA), which is involved in brain development, nerve regeneration, wound healing and tissue remodeling. We have recently shown that Plaur, which encodes uPAR, is an early response gene in murine brain. Assumingly, diverse functions of Plaur might be attributed to hypothetical, unidentified microRNAs encoded within introns of the Plaur gene. Using a bioinformatic approach we identified novel small RNAs within the Plaur gene and named them Plaur-miR1-3p and Plaur-miR1-5p. We confirmed Plaur-dependent expression of Plaur-miR1-3p and Plaur-miR1-5p in the mouse brain and mouse neuroblastoma Neuro2a cells. Utilizing an in silico MR-microT algorithm in DianaTools we selected two target genes - Mef2d and Emx2 with the highest binding scores to small RNAs selected from identified Plaur-Pre-miR1. Furthermore, sequencing of mouse brain samples for Plaur-miR1-5p target genes revealed two more genes-Nrip3 and Snrnp200. The expression of Emx2, Mef2d, and Snrnp200 in the mouse brain and Mef2d and Snrnp200 in Neuro2a cells correlated with expression of Plaur and small RNAs-Plaur-miR1-3p and Plaur-miR1-5p. Finally, we demonstrated elevated MEF2D protein expression in the mouse brain after Plaur induction and displayed activating effects of Plaur-miR1-5p on Mef2d expression in Neuro2a cells using Luciferase reporter assay. In conclusion, we have identified Plaur-miR1-3p and Plaur-miR1-5p as novel small RNAs encoded in the Plaur gene. This finding expands the current understanding of Plaur function in brain development and functioning.
RESUMO
uPAR is a membrane receptor that binds extracellular protease urokinase, contributes to matrix remodeling and plays a crucial role in cellular adhesion, proliferation, survival, and migration. uPAR overexpression in tumor cells promotes mitogenesis, opening a prospective avenue for targeted therapy. However, uPAR targeting in cancer has potential risks. We have recently shown that uPAR downregulation in neuroblastoma promotes epithelial-mesenchymal transition (EMT), potentially associated with metastasis and chemoresistance. We used data mining to evaluate the role of uPAR expression in primary and relapsed human neuroblastomas. To model the decreased uPAR expression, we targeted uPAR using CRISPR/Cas9 and shRNA in neuroblastoma Neuro2a cells and evaluated their chemosensitivity in vitro as well as tumor growth and metastasis in vivo. We demonstrate that the initially high PLAUR expression predicts poor survival in human neuroblastoma. However, relapsed neuroblastomas have a significantly decreased PLAUR expression. uPAR targeting in neuroblastoma Neuro2a cells leads to p38 activation and an increased p21 expression (suggesting a dormant phenotype). The dormancy in neuroblastoma cells can be triggered by the disruption of uPAR-integrin interaction. uPAR-deficient cells are less sensitive to cisplatin and doxorubicin treatment and exhibit lower p53 activation. Finally, low uPAR-expressing Neuro2a cells formed smaller primary tumors, but more frequent metastasis in mice. To the best of our knowledge, this is the first study revealing the pathological role of dormant uPAR-deficient cancer cells having a chemoresistant and motile phenotype.
RESUMO
COVID-19 pandemic has posed a severe healthcare challenge calling for an integrated approach in determining the clues for early non-invasive diagnostics of the potentially severe cases and efficient patient stratification. Here we analyze the clinical, laboratory and CT scan characteristics associated with high risk of COVID-19-related death outcome in the cohort of severely-ill patients in Russia. The data obtained reveal that elevated dead lymphocyte counts, decreased early apoptotic lymphocytes, decreased CD14+/HLA-Dr+ monocytes, increased expression of JNK in PBMCs, elevated IL-17 and decreased PAI-1 serum levels are associated with a high risk of COVID-19-related mortality thus suggesting them to be new prognostic factors. This set of determinants could be used as early predictors of potentially severe course of COVID-19 for trials of prevention or timely treatment.
Assuntos
COVID-19/mortalidade , Interleucina-17/sangue , Inibidor 1 de Ativador de Plasminogênio/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/sangue , Feminino , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Pandemias , Projetos Piloto , Prognóstico , Federação Russa/epidemiologia , Adulto JovemRESUMO
Neurotrophin receptors regulate neuronal survival and network formation, as well as synaptic plasticity in the brain via interaction with their ligands. Here, we examined early changes in the expression of neurotrophin receptor genes Ntk1 (TrkA), Ntrk2 (TrkB), Ntrk3 (TrkC), Ngfr (p75NTR) and miRNAs that target theses gens in the mouse brain after induction of seizure activity by pentylenetetrazol. We found that expression of Ntrk3 and Ngfr was upregulated in the cortex and the hippocampus 1-3 hours after the seizures, while Ntrk2 expression increased after 3-6 hours in the anterior cortex and after 1 and 6 hours in the hippocampus. At the same time, the ratio of Bcl-2/Bax signaling proteins increased in the anterior and posterior cortex, but not in the hippocampus, suggesting the activation of anti-apoptotic signaling. Expression of miRNA-9 and miRNA-29a, which were predicted to target Ntrk3, was upregulated in the hippocampus 3 hours after pentylenetetrazol injection. Therefore, early cellular response to seizures in the brain includes induction of the Ntrk2, Ntrk3, Ngfr, miRNA-9, and miRNA-29a expression, as well as activation of Bcl-2 and Bax signaling pathways, which may characterize them as important mediators of neuronal adaptation and survival upon induction of the generalized brain activity.
Assuntos
Encéfalo/efeitos dos fármacos , MicroRNAs/genética , Neurônios/efeitos dos fármacos , Pentilenotetrazol/farmacologia , Convulsões/genética , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Regulação da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/biossíntese , Neurônios/metabolismo , Neurônios/patologia , Receptores de Fator de Crescimento Neural/genética , Receptores de Fator de Crescimento Neural/metabolismo , Convulsões/induzido quimicamente , Convulsões/metabolismo , Convulsões/patologiaRESUMO
Topical advances in studying molecular and cellular mechanisms responsible for regeneration in the peripheral nervous system have highlighted the ability of the nervous system to repair itself. Still, serious injuries represent a challenge for the morphological and functional regeneration of peripheral nerves, calling for new treatment strategies that maximize nerve regeneration and recovery. This review presents the canonical view of the basic mechanisms of nerve regeneration and novel data on the role of exosomes and their transferred microRNAs in intracellular communication, regulation of axonal growth, Schwann cell migration and proliferation, and stromal cell functioning. An integrated comprehensive understanding of the current mechanistic underpinnings will open the venue for developing new clinical strategies to ensure full regeneration in the peripheral nervous system.
Assuntos
Regeneração Nervosa/fisiologia , Nervos Periféricos/metabolismo , Nervos Periféricos/fisiologia , Animais , Axônios/fisiologia , Exossomos , Humanos , MicroRNAs , Neurogênese , Traumatismos dos Nervos Periféricos/terapia , Sistema Nervoso Periférico , Células de Schwann/fisiologia , Células EstromaisRESUMO
By 2003, the Human Genome project had been completed; however, it turned out that 97% of genome sequences did not encode proteins. The explanation came later when it was found the untranslated DNA contain sequences for short microRNAs (miRNAs) and long noncoding RNAs that did not produce any mRNAs or tRNAs, but instead were involved in the regulation of gene expression. Initially identified in the cytoplasm, miRNAs have been found in all cell compartments, where their functions are not limited to the degradation of target mRNAs. miRNAs that are secreted into the extracellular space as components of exosomes or as complexes with proteins, participate in morphogenesis, regeneration, oncogenesis, metastasis, and chemoresistance of tumor cells. miRNAs play a dual role in oncogenesis: on one hand, they act as oncogene suppressors; on the other hand, they function as oncogenes themselves and inactivate oncosuppressors, stimulate tumor neoangiogenesis, and mediate immunosuppressive processes in the tumors, The review presents current concepts of the miRNA biogenesis and their functions in the cytoplasm and nucleus with special focus on the noncanonical mechanisms of gene regulation by miRNAs and involvement of miRNAs in oncogenesis, as well as the authors' opinion on the role of miRNAs in metastasis and formation of the premetastatic niche.
Assuntos
MicroRNAs/metabolismo , Neoplasias/metabolismo , Exossomos/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/genéticaRESUMO
Gene therapy is one of the promising approaches for regenerative medicine. Local and long-term expression of essential growth factors allows to achieve the desired therapeutic effect. However, some aspects of prolonged usage of genetic constructs encoding growth factors, such as toxicity, mutagenicity, genotoxicity, and ability to disseminate from the injection site and mediate ectopic expression of therapeutic proteins, are poorly investigated. These aspects of gene therapy drugs' usage became the subject of this study. To study plasmid biodistribution, toxicity, mutagenicity, and genotoxicity, we used previously described bicistronic genetic construct encoding human brain-derived neurotrophic factor (hBDNF) and human urokinase plasminogen activator (huPA) for nerve repair. Biodistribution studies were conducted in mice: a course of intramuscular plasmid injections was followed by the study of the content of the plasmid (real-time polymerase chain reaction) and recombinant proteins (enzyme-linked immunosorbent assay) in murine organs and tissues. The study of the plasmid chronic toxicity was carried out on rats with registration of their weight dynamics, neurological status, emotional state, and blood test parameters. The mutagenicity of the plasmid was studied in an in vivo DNA comet test in mice. Plasmid genotoxicity was investigated in the model of somatic recombination in Drosophila females. We have shown that plasmids can disseminate from the injection site, but do not mediate ectopic expression of growth factors upon repeated intramuscular injections. The studied plasmid also does not reveal toxic, mutagenic, or genotoxic effects. During the toxicological study on rats, we have shown that daily injections of this genetic construct, despite its ability to disseminate from the injection site, do not affect the physical, cognitive, and emotional state of experimental animals. We have demonstrated the safety of the bicistronic plasmid, encoding hBDNF and huPA, upon its repeated administration. The properties of genetic constructs strongly depend on their sequence and delivery approach, which requires conducting of their safety studies in each specific case. Impact statement Gene therapy is one of the promising approaches for regenerative medicine. Local and long-term expression of essential growth factors allows to achieve the desired therapeutic effect. However, some aspects of prolonged usage of genetic constructs encoding growth factors, such as toxicity, mutagenicity, genotoxicity, and ability to disseminate from the injection site and mediate ectopic expression of therapeutic proteins, are poorly investigated. These aspects of gene therapy became the subject of this study. To our knowledge, this is a unique study that provides a thorough safety investigation of a bicistronic plasmid after its readministration.
Assuntos
DNA , Animais , Feminino , Camundongos , Plasmídeos/genética , Ratos , Distribuição TecidualRESUMO
NeurotrophiÑ factors play a key role in the development, differentiation, and survival of neurons and nerve regeneration. In the present study, we evaluated the effect of certain neurotrophic factors (NGF, BDNF, and GDNF) on axon growth and migration of Nestin-green fluorescent protein (GFP)-positive cells using a 3D model of dorsal root ganglion (DRG) explant culture in Matrigel. Our method generally represents a convenient model for assessing the effects of soluble factors and therapeutic agents on axon growth and nerve regeneration in R&D studies. By analyzing the DRG explants in ex vivo culture for 21 days, one can evaluate the parameters of neurite outgrowth and the rate of cell migration from the DRG explants into the Matrigel. For the current study, we used Nestin-GFP-expressing mice in which neural precursors express Nestin and the green fluorescent protein (GFP) under the same promoter. We revealed that GDNF significantly (two fold) stimulated axon outgrowth (p < 0.05), but not BDNF or NGF. It is well-known that axon growth can be stimulated by activated glial cells that fulfill a trophic function for regenerating nerves. For this reason, we evaluated the number of Nestin-GFP-positive cells that migrated from the DRG into the Matrigel in our 3D ex vivo explant model. We found that NGF and GDNF, but not BDNF, stimulated the migration of Nestin-GFP cells compared to the control (p < 0.05). On the basis of the aforementioned finding, we concluded that GDNF had the greatest stimulating potential for axon regeneration, as it stimulated not only the axon outgrowth, but also glial cell migration. Although NGF significantly stimulated glial cell migration, its effect on axon growth was insufficient for axon regeneration.
RESUMO
The urokinase system is involved in a variety of physiological processes, such as fibrinolysis, matrix remodeling, wound healing, and regeneration. Upon binding to its cognate receptor urokinase-type plasminogen activator receptor (uPAR), urokinase-type plasminogen activator (uPA) catalyzes the conversion of plasminogen to plasmin and the activation of matrix metalloproteases. Apart from this, uPA-uPAR interaction can lead to the activation of transcription factors, mitogen-activated protein kinase signaling pathways and RTK cascades. Elevated expression of uPA and uPAR is markedly associated with cancer progression and metastasis and correlates with a poor prognosis in clinics. Targeting the urokinase system has proved to be effective in experimental models in vitro and in vivo, however, in clinics the inhibition of the uPA/uPAR system has fallen short of expectations, suggesting that the question of the functional relevance of uPA/uPAR system is far from being moot. Recently, using CRISPR/Cas9 technology, we have shown that uPAR knockout decreases the proliferation of neuroblastoma Neuro2a cells in vitro. In the present study we demonstrate that uPAR expression is essential for maintaining the epithelial phenotype in Neuro2a cells and that uPAR silencing promotes epithelial-mesenchymal transition (EMT) and increased cell migration. Accordingly, uPAR knockout results in the downregulation of epithelial markers (E-cadherin, occludin, and claudin-5) and in the increase of mesenchymal markers (N-cadherin, α-smooth muscle actin, and interleukin-6). In search of the molecular mechanism underlying these changes, we identified uPA as a key component. Two key insights emerged as a result of this work: in the absence of uPAR, uPA is translocated into the nucleus where it is presumably involved in the activation of transcription factors (nuclear factor κB and Snail) resulting in EMT. In uPAR-expressing cells, uPAR functions as a uPA "trap" that binds uPA on the cell surface and promotes controlled uPA internalization and degradation in lysosomes.
Assuntos
Núcleo Celular/genética , Proteínas de Membrana/genética , Neuroblastoma/genética , Receptores de Ativador de Plasminogênio Tipo Uroquinase/genética , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Inativação de Genes , Humanos , Neuroblastoma/patologia , Transdução de SinaisRESUMO
Timely nerve restoration is an important factor for the successful regeneration of tissues and organs. It is known that axon regeneration following nerve injury is a multifactorial process that depends on the local expression of neurotrophins, including brain-derived neurotrophic factor (BDNF). Along with the survival of neurons, the active reorganization of the extracellular matrix is an important step for the growth of axons to their targets. Urokinase serine protease is part of the plasminogen activator system, which provides the vectoriality of the process of fibrinolysis and matrix reorganization, facilitating the growth of nerves to their targets. Based on this and in view of the results of our previous studies, we suggest that a combined bicistronic plasmid encoding the complementary proteins BDNF and urokinase may be beneficial in nerve regeneration. The ability of this bicistronic plasmid to stimulate nerve restoration was confirmed by in vitro stimulation of Neuro2a neurite growth and in vivo nerve conductivity and histology studies. To our knowledge, this is the first article that demonstrates the effectiveness of a bicistronic plasmid containing the human genes BDNF and urokinase plasminogen activator in the regeneration of the injured peripheral nerve. The results obtained demonstrate that plasmid vectors encoding several complementary-active therapeutic proteins may serve as a basis for developing prospective treatments for a wide range of multicomponent neural system disorders, such as nerve trauma. SIGNIFICANCE STATEMENT: This study is the first to show the effectiveness of using a bicistronic plasmid encoding complementary-active human protein brain-derived neurotrophic factor and urokinase plasminogen activator in the regeneration of the crushed peripheral nerve in a murine model.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Regeneração Nervosa/genética , Doenças do Sistema Nervoso Periférico/genética , Ativador de Plasminogênio Tipo Uroquinase/genética , Animais , Fator Neurotrófico Derivado do Encéfalo/administração & dosagem , Linhagem Celular Tumoral , Modelos Animais de Doenças , Células HEK293 , Humanos , Injeções Intramusculares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doenças do Sistema Nervoso Periférico/terapia , Plasmídeos , Transfecção , Ativador de Plasminogênio Tipo Uroquinase/administração & dosagemRESUMO
Epileptogenesis progressively leads to the rearrangement of normal neuronal networks into more excitable ones and can be viewed as a form of neuroplasticity, the molecular mechanisms of which still remain obscure. Here, we studied pentylenetetrazole seizure-induced regulation of genes for plasminogen activator system in the mouse brain. We found that expression of tissue plasminogen activator (tPA) and urokinase receptor (uPAR) mRNA was strongly increased in the mouse cerebral cortex, hippocampus, striatum and amygdala as early as 3 hr after pentylenetetrazole seizures. Such early activity-induced expression of uPAR in the central nervous system has not been demonstrated before. uPAR mRNA accumulation was followed by elevation of uPAR protein, indicating a complete transcription-translation process. Both tPA gene induction and uPAR gene induction were independent of the protein synthesis, suggesting that they are regulated by neural activity as immediate-early genes. In contrast to tPA and uPAR genes, the expression of which returned to the basal level 6 hr following seizures, urokinase and plasminogen activator inhibitor-1 gene expression showed a delayed activation only at 3 days after seizures. In conclusion, our results suggest an important sensitivity of the brain plasminogen activator system to seizure activity which raises the question of its role in activity-dependent neural tissue remodeling in pathological and normal conditions.
Assuntos
Pentilenotetrazol , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Convulsões , Ativador de Plasminogênio Tipo Uroquinase , Animais , Encéfalo/metabolismo , Genes Precoces , Camundongos , Pentilenotetrazol/toxicidade , Receptores de Ativador de Plasminogênio Tipo Uroquinase/genética , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Convulsões/induzido quimicamente , Convulsões/genética , Ativador de Plasminogênio Tecidual/genética , Ativador de Plasminogênio Tipo Uroquinase/genética , Ativador de Plasminogênio Tipo Uroquinase/metabolismoRESUMO
IMPACT STATEMENT: Cell lines represent convenient models to elucidate specific causes of multigenetic and pluricausal diseases, to test breakthrough regenerative technologies. Most commonly used cell lines surpass diploid cells in their accessibility for delivery of large DNA molecules and genome editing, but the main obstacles for obtaining cell models with knockout-targeted protein from aneuploid cells are multiple allele copies and karyotype/phenotype heterogeneity. In the study, we report an original approach to CRISPR-/Cas9-mediated genome modification of aneuploid cell cultures to create functional cell models, achieving highly efficient targeted protein knockout and avoiding "clonal effect" (for the first time to our knowledge).