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Neurotensin (NTS)-polyplex is a multicomponent nonviral vector that enables gene delivery via internalization of the neurotensin type 1 receptor (NTSR1) to dopaminergic neurons and cancer cells. An approach to improving its therapeutic safety is replacing the viral karyophilic component (peptide KPSV40; MAPTKRKGSCPGAAPNKPK), which performs the nuclear import activity, by a shorter synthetic peptide (KPRa; KMAPKKRK). We explored this issue and the mechanism of plasmid DNA translocation through the expression of the green fluorescent protein or red fluorescent protein fused with KPRa and internalization assays and whole-cell patch-clamp configuration experiments in a single cell together with importin α/ß pathway blockers. We showed that KPRa electrostatically bound to plasmid DNA increased the transgene expression compared with KPSV40 and enabled nuclear translocation of KPRa-fused red fluorescent proteins and plasmid DNA. Such translocation was blocked with ivermectin or mifepristone, suggesting importin α/ß pathway mediation. KPRa also enabled NTS-polyplex-mediated expression of reporter or physiological genes such as human mesencephalic-derived neurotrophic factor (hMANF) in dopaminergic neurons in vivo. KPRa is a synthetic monopartite peptide that showed nuclear import activity in NTS-polyplex vector-mediated gene delivery. KPRa could also improve the transfection of other nonviral vectors used in gene therapy.
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Portadores de Fármacos/síntese química , Técnicas de Transferência de Genes , Vetores Genéticos/administração & dosagem , Neurotensina/administração & dosagem , Fragmentos de Peptídeos/síntese química , Transporte Ativo do Núcleo Celular , Animais , Linhagem Celular , Núcleo Celular/metabolismo , Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/metabolismo , Terapia Genética/métodos , Vetores Genéticos/genética , Masculino , Camundongos , Modelos Animais , Nanopartículas/química , Neurotensina/genética , Neurotensina/farmacocinética , Técnicas de Patch-Clamp , Plasmídeos/genética , Ratos , Receptores de Neurotensina/metabolismo , Análise de Célula Única , Técnicas EstereotáxicasRESUMO
BACKGROUND: The neurotrophin Brain-Derived Neurotrophic Factor (BDNF) influences nigral dopaminergic neurons via autocrine and paracrine mechanisms. The reduction of BDNF expression in Parkinson's disease substantia nigra (SN) might contribute to the death of dopaminergic neurons because inhibiting BDNF expression in the SN causes parkinsonism in the rat. This study aimed to demonstrate that increasing BDNF expression in dopaminergic neurons of rats with one week of 6-hydroxydopamine lesion recovers from parkinsonism. The plasmids phDAT-BDNF-flag and phDAT-EGFP, coding for enhanced green fluorescent protein, were transfected using neurotensin (NTS)-polyplex, which enables delivery of genes into the dopaminergic neurons via neurotensin-receptor type 1 (NTSR1) internalization. RESULTS: Two weeks after transfections, RT-PCR and immunofluorescence techniques showed that the residual dopaminergic neurons retain NTSR1 expression and susceptibility to be transfected by the NTS-polyplex. phDAT-BDNF-flag transfection did not increase dopaminergic neurons, but caused 7-fold increase in dopamine fibers within the SN and 5-fold increase in innervation and dopamine levels in the striatum. These neurotrophic effects were accompanied by a significant improvement in motor behavior. CONCLUSIONS: NTS-polyplex-mediated BDNF overexpression in dopaminergic neurons has proven to be effective to remit hemiparkinsonism in the rat. This BDNF gene therapy might be helpful in the early stage of Parkinson's disease.
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Fator Neurotrófico Derivado do Encéfalo/biossíntese , Neurônios Dopaminérgicos , Neurotensina , Doença de Parkinson , Substância Negra , Transfecção/métodos , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Terapia Genética/métodos , Masculino , Neurotensina/química , Neurotensina/farmacologia , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Doença de Parkinson/terapia , Ratos , Ratos Wistar , Receptores de Neurotensina/metabolismo , Substância Negra/metabolismo , Substância Negra/patologiaRESUMO
BACKGROUND: The anti-inflammatory effect of the cerebral dopamine neurotrophic factor (CDNF) was shown recently in primary glial cell cultures, yet such effect remains unknown both in vivo and in 6-hydroxydopamine (6-OHDA) models of Parkinson's disease (PD). We addressed this issue by performing an intranigral transfection of the human CDNF (hCDNF) gene in the critical period of inflammation after a single intrastriatal 6-OHDA injection in the rat. METHODS: At day 15 after lesion, the plasmids p3xNBRE-hCDNF or p3xNBRE-EGFP, coding for enhanced green florescent protein (EGFP), were transfected into the rat substantia nigra (SN) using neurotensin (NTS)-polyplex. At day 15 post-transfection, we measured nitrite and lipoperoxide levels in the SN. We used ELISA to quantify the levels of TNF-α, IL-1ß, IL-6, endogenous rat CDNF (rCDNF) and hCDNF. We also used qRT-PCR to measure rCDNF and hCDNF transcripts, and immunofluorescence assays to evaluate iNOS, CDNF and glial cells (microglia, astrocytes and Neuron/Glial type 2 (NG2) cells). Intact SNs were additional controls. RESULTS: In the SN, 6-OHDA triggered nitrosative stress, increased inflammatory cytokines levels, and activated the multipotent progenitor NG2 cells, which convert into astrocytes to produce rCDNF. In comparison with the hemiparkinsonian rats that were transfected with the EGFP gene or without transfection, 6-OHDA treatment and p3xNBRE-hCDNF transfection increased the conversion of NG2 cells into astrocytes resulting in 4-fold increase in the rCDNF protein levels. The overexpressed CDNF reduced nitrosative stress, glial markers and IL-6 levels in the SN, but not TNF-α and IL-1ß levels. CONCLUSION: Our results show the anti-inflammatory effect of CDNF in a 6-OHDA rat of Parkinson's disease. Our results also suggest the possible participation of TNF-α, IL-1ß and IL-6 in rCDNF production by astrocytes, supporting their anti-inflammatory role.
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Fatores de Crescimento Neural/biossíntese , Fatores de Crescimento Neural/genética , Oxidopamina/toxicidade , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo , Transfecção , Animais , Humanos , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/metabolismo , Injeções Intraventriculares , Masculino , Oxidopamina/administração & dosagem , Ratos , Ratos WistarRESUMO
Living Donor Liver Transplantation (LDLT) is a promising approach to treating end-stage liver diseases, however, some post-operatory complications such as pneumonia, bacteremia, urinary tract infections, and hepatic dysfunction have been reported. In murine models using partial hepatectomy (PHx), a model that emulates LDLT, it has been determined that the synthesis of hepatic cell proliferation factors that are associated with noradrenaline synthesis are produced in locus coeruleus (LC). In addition, studies have shown that PHx decreases GABA and 5-HT2A receptors, promotes loss of dendritic spines, and favors microgliosis in rat hippocampus. The GABA and serotonin-altered circuits suggest that catecholaminergic neurons such as dopamine and noradrenaline neurons, which are highly susceptible to cellular stress, can also be damaged. To understand post-transplant affections and to perform well-controlled studies it is necessary to know the potential causes that explain as a liver surgical procedure can produce brain damage. In this paper, we review several cellular processes that could induce gliosis in LC after rat PHx.
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Bromodeoxyuridine (BrdU) is used in studies related to cell proliferation and neurogenesis. The multiple intraperitoneal injections of this molecule could favor liver function profile changes. In this study, we evaluate the systemic and hepatocellular impact of BrdU in male adult Wistar rats in 30 %-partial hepatectomy (PHx) model. The rats received BrdU 50 mg/Kg by intraperitoneal injection at 0.5, 1, 2, 3, 6, 9 and 16 days after 30 %-PH. The rats were distributed into four groups as follows, control, sham, PHx/BrdU(-) and PHx/BrdU(+). On day 16, we evaluated hepatocellular nuclei and analyzed histopathological features by haematoxylin-eosin stain and apoptotic profile was qualified by caspase-3 presence. The systemic effect was evaluated by liver markers such as alanine transferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), alkaline phosphatase (AP), bilirubin, total proteins and serum albumin content. The statistical analysis consisted of a student t-test and one-way ANOVA. BrdU did not induce apoptosis or hepatocellular damage in male rats. Multiple administrations of BrdU in male rats did not induce significant decrease body weight, but increased serum ALT and LDH levels were found. Our results show that the BrdU does not produce hepatocellular damage.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Ratos , Masculino , Animais , Ratos Wistar , Bromodesoxiuridina/farmacologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Fígado/patologia , Alanina Transaminase/metabolismo , Alanina Transaminase/farmacologia , Aspartato Aminotransferases/metabolismo , Aspartato Aminotransferases/farmacologiaRESUMO
Overexpression of neurotrophic factors in nigral dopamine neurons is a promising approach to reverse neurodegeneration of the nigrostriatal dopamine system, a hallmark in Parkinson's disease. The human cerebral dopamine neurotrophic factor (hCDNF) has recently emerged as a strong candidate for Parkinson's disease therapy. This study shows that hCDNF expression in dopamine neurons using the neurotensin-polyplex nanoparticle system reverses 6-hydroxydopamine-induced morphological, biochemical, and behavioral alterations. Three independent electron microscopy techniques showed that the neurotensin-polyplex nanoparticles containing the hCDNF gene, ranging in size from 20 to 150 nm, enabled the expression of a secretable hCDNF in vitro. Their injection in the substantia nigra compacta on day 21 after the 6-hydroxydopamine lesion resulted in detectable hCDNF in dopamine neurons, whose levels remained constant throughout the study in the substantia nigra compacta and striatum. Compared with the lesioned group, tyrosine hydroxylase-positive (TH+) nigral cell population and TH+ fiber density rose in the substantia nigra compacta and striatum after hCDNF transfection. An increase in ßIII-tubulin and growth-associated protein 43 phospho-S41 (GAP43p) followed TH+ cell recovery, as well as dopamine and its catabolite levels. Partial reversal (80%) of drug-activated circling behavior and full recovery of spontaneous motor and non-motor behavior were achieved. Brain-derived neurotrophic factor recovery in dopamine neurons that also occurred suggests its participation in the neurotrophic effects. These findings support the potential of nanoparticle-mediated hCDNF gene delivery to develop a disease-modifying treatment against Parkinson's disease. The Institutional Animal Care and Use Committee of Centro de Investigación y de Estudios Avanzados approved our experimental procedures for animal use (authorization No. 162-15) on June 9, 2019.
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PURPOSE: The main goal of this study was to determine the relationship of cleaved-caspase-3 (C3)-related apoptosis and hepatic proliferation, during the liver repopulation in a living liver donor rat model. MATERIAL/METHODS: Thirty-three animals were randomized into eleven groups and evaluated on postoperative from 3 âh until 384 âh after 30%-partial hepatectomy (30%-PHx). Liver sections (5 âµm) were processed by hematoxylin-eosin, and immunostaining for C3, accompanied by hepatic function test. C3 content and the hepatic lobule enlargement were analyzed by optical density, followed by cell counting. RESULTS: Transient variations of alanine transferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were found. Significant increase in the C3 levels, and cell nuclei number, were detected at 12 âh and 48 âh after 30%-PHx, evidencing a correlation of p â= â-0.3679. CONCLUSION: In the 30%-PHx rat model, C3-related apoptosis prevents proliferative pathological conditions during the hepatic lobule re-modeling.
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Apoptose , Caspase 3/metabolismo , Proliferação de Células , Hepatectomia/métodos , Regeneração Hepática , Fígado/patologia , Animais , Caspase 3/genética , Doadores Vivos/estatística & dados numéricos , Masculino , Ratos , Ratos WistarRESUMO
BackgroundDasapatrachurnam (DPC), a multicurative powder prepared from the leaves of 10 green leafy vegetables, was developed recently with known ethnobotanical and ethnopharmacological significance. However, its functional role in curing a disease is not yet scientifically proven. The present study aims at performing the phytochemical screening of DPC and exploring its possible activity as bacteriostatic, antineoplastic and anti-inflammatory. MethodsWe performed qualitative and Fourier transform infrared spectroscopy (FTIR) to find out the presence of active compounds and tested the bacteriostatic activity in four bacterial strains namely Bacillus subtilis, Escherichia coli, Streptococcus pyogenes and Staphylococcus aureus by agar well diffusion method. We further explored the antineoplastic activity in vitro in C6 and HEK293 cell lines by cell viability assay and the anti-inflammatory activity in the ovalbumin-induced inflammation in male Wistar rats. ResultsDPC showed 60% solubility in PBS and showed the presence of flavonoids and glycosides. FTIR results indicated the presence of alkyl, ketone and aldehyde groups. The bacteriostatic activity of DPC was higher (60%) in E.coli and lower (8%) in S.aureus, when compared to streptomycin. The anti-cancerous activity of DPC in C6 and HEK293 cancer cells was similar to their respective positive controls, curcumin and camptothecin. The anti-inflammatory activity of DPC was more evident with local administration in all the parameters studied in brain hippocampus, kidney, liver and spleen in ovalbumin-induced rats. ConclusionOur results, for the first time, suggest the potentiality of the DPC in treating bacterial diseases, cancer and also inflammation. Our results also suggest the possible therapeutic role of DPC in treating chronic kidney disease.
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Suplementos Nutricionais/análise , Compostos Fitoquímicos/farmacologia , Folhas de Planta/química , Preparações de Plantas/farmacologia , Verduras/química , Animais , Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Bactérias/efeitos dos fármacos , Flavonoides/análise , Glicosídeos/análise , Células HEK293 , Humanos , Masculino , Pós , Ratos , Ratos WistarRESUMO
OBJECTIVES: Cassava (Manihot esculenta Crantz) contains cyanogenic glycosides (linamarin and lotaustralin) that have been associated with neurological disorders in humans and rats. In basal ganglia, the dopaminergic neurons of substantia nigra pars compacta (SNpc) show high cytotoxic susceptibility; therefore, the chronic consumption of cassava (CCC) could induce neurodegeneration in SNpc. In this study we examine the impact of CCC on the integrity of the nigrostriatal system, including apoptosis and microgliosis. MATERIALS AND METHODS: Male Wistar rats were administered cassava juice daily (3.57 g/kg and 28.56 g/kg, per os) or linamarin (0.15 mg/ml, IP), and its effects were evaluated in rota-rod and swim tests at days 7, 14, 21, 28, and 35 of administration. In SNpc, oxidative/nitrosative stress was determined by malondialdehyde/4-hydroxyalkenals (MDA-4-HAD) and nitrite contents. Tyrosine hydroxylase immunoreactivity (TH-IR) was evaluated in SNpc, neostriatum (NE), and nucleus accumbens (NA). Apoptosis and microgliosis were determined by active-caspase-3 (C3) and CD11b/c (OX42) expression in the medial region of SNpc. RESULTS: Chronic administration of cassava juice, or linamarin, increased motor impairment. The rats that received 28.56 g/kg cassava showed increased MDA-4-HAD content in SNpc and nitrite levels in NE with respect to controls. Significant loss of TH-IR in SNpc, NE, and NA was not found. The 28.56 g/kg cassava administration produced dopaminergic atrophy and microgliosis, whereas linamarin induced hypertrophy and C3-related apoptosis in SNpc. CONCLUSION: CCC induces cellular stress on dopaminergic neurons, which could contribute to motor impairment in the rat.
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Lipopolysaccharide (LPS) is a potent immunogen when administered locally and/or systemically. The peripheral immunization with LPS could contribute to the progression of neurological diseases because a strong link between neuroinflammation and dopaminergic degeneration has been found. The switch between the survival and neuronal death in substantia nigra could be related to M1 (neurotoxic) and M2 (neuroprotective) microglia phenotypes. In this review, we present the current findings about microglia roles, biomarkers, and natural or synthetic immune modulators determined in the LPS-based murine model.
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Modelos Animais de Doenças , Inflamação/imunologia , Lipopolissacarídeos/farmacologia , Microglia/imunologia , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Humanos , Inflamação/induzido quimicamente , Microglia/efeitos dos fármacosRESUMO
Highly bioavailable plant phospholipid complex that can reverse aluminum maltolate (AlM)-induced toxicity is not yet reported. Hence, the present study was planned to investigate the impact of oxidative stress and apoptotic changes provoked by Al and ameliorative role of Bacopa phospholipid complex (BPC) in albino rats. The levels of antioxidant enzymes such as superoxide dismutase (SOD), catalase activity (CAT), glutathione peroxidase (GPx), and thiobarbituric acid-reactive substance (TBA-RS) were measured and immunohistochemistry analysis of apoptotic markers, Bax and Bcl-2, was done from the four brain regions such as the hippocampus, cerebral cortex, cerebellum, and medulla oblongata. The levels of antioxidant enzymes and apoptotic markers that were decreased on AlM induction showed a significant increase in their levels, almost as observed in the control, when treated with BPC and Bm. Our results indicate that both BPC and Bm showed a therapeutic effect against AlM toxicity; however, it was found that the therapeutic potential of BPC was more pronounced than Bm against AlM-induced neurotoxicity.
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Antioxidantes/farmacologia , Encéfalo/fisiologia , Compostos Organometálicos/toxicidade , Extratos Vegetais/farmacologia , Pironas/toxicidade , Animais , Bacopa/química , Encéfalo/efeitos dos fármacos , Catalase/metabolismo , Cerebelo/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Hipocampo/efeitos dos fármacos , Masculino , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Fosfolipídeos , Ratos , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido TiobarbitúricoRESUMO
The peripheral inflammatory stimulus could induce cell damage in peripheral organs and activate microglial cells in the brain. One such stimulus was given to adult male Wistar rats by injecting different concentrations of lipopolysaccharide (LPS; 50, 300, 500 ïg/kg and 5 mg/kg i.p.). To verify the systemic effect of the LPS administration, the serum content of C-reactive protein (CRP), the variation of body weight and cellular changes in the spleen, liver and kidney were determined. Motor impairment was evaluated by rotarod and open field tests. Microglia activation and dopaminergic degeneration was confirmed by immunolabelling for CD11b/c (microglia) and tyrosine hydroxylase (TH), respectively. The cell counting was performed in substantia nigra pars compacta (SNpc), microglial activation was explored in SNpc, substantia nigra pars reticulata (SNpr), substantia nigra pars compacta dorsal (SNcd) and the ventral tegmental area (VTA). For the statistical analysis, one-way ANOVA followed by Tukey post hoc test (p ≤ 0.05) was used. On day 7 post intraperitoneal administration of LPS, cellular atrophy was detected in the liver, kidney and spleen at 5 mg/kg, without significant changes in CRP levels. Body weight loss and motor impairment was present only on day 1 post LPS administration. The dosage of 500 ïg/kg and 5 mg/kg of LPS caused the loss of dopaminergic neurons (40%) in SNpc and microglia migration in a dose-dependent manner in SNcd, SNpc and SNpr. LPS-induced endotoxemia favours damage to the peripheral organs and microglial migration in a dose-dependent manner in rat substantia nigra.
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Endotoxemia/patologia , Lipopolissacarídeos/toxicidade , Microglia/patologia , Substância Negra/patologia , Animais , Movimento Celular , Neurônios Dopaminérgicos/patologia , Endotoxemia/induzido quimicamente , Masculino , Ratos , Ratos WistarRESUMO
OBJECTIVES: Parkinson's disease (PD) is characterized by motor and cognitive dysfunctions. The progressive degeneration of dopamine-producing neurons that are present in the substantia nigra pars compacta (SNpc) has been the main focus of study and PD therapies since ages. MATERIALS AND METHODS: In this manuscript, a systematic revision of experimental and clinical evidence of PD-associated cell process was conducted. RESULTS: Classically, the damage in the dopaminergic neuronal circuits of SNpc is favored by reactive oxidative/nitrosative stress, leading to cell death. Interestingly, the therapy for PD has only focused on avoiding the symptom progression but not in finding a complete reversion of the disease. Recent evidence suggests that the renin-angiotensin system imbalance and neuroinflammation are the main keys in the progression of experimental PD. CONCLUSION: The progression of neurodegeneration in SNpc is due to the complex interaction of multiple processes. In this review, we analyzed the main contribution of four cellular processes and discussed in the perspective of novel experimental approaches.