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1.
Peptides ; 181: 171294, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39265809

RESUMO

Endometriosis is a gynecological condition characterized by the growth of endometrium-like tissues outside of the uterine cavity. Currently available drugs are efficacious in treating endometriosis-related pain, however it's not a targeted treatment. The aim of this work is to evaluate the effects of R-954, a bradykinin B1 receptor antagonist, in a murine model of endometriosis. The model was induced in animals through autologous transplantation of part of the uterine horn. After 51 days, it was observed that implants developed into endometriotic lesions. The administration of R-954 or progesterone, for 15 consecutive days, prevented the progression of cyst development, reduced the size and weight of the cysts. Both treatments also reduced cellular infiltrate and production of inflammatory mediators (interleukin-1ß, interleukin-6, tumor necrosis factor). However, only R-954 decreased angiogenic factors (VEGF and VEGF receptor). In addition, treatment with the antagonist did not interfere in the females' estrous cycle, as well as prevented gestational losses (reduction in the number of intermediate resorptions in pregnant females with endometriosis). Data suggested that R-954 has anti-inflammatory and anti-angiogenic effects; does not influence the estrous cycle; and prevents the number of gestational losses suggesting it as a good candidate for endometriosis treatment.

2.
Mol Psychiatry ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152331

RESUMO

Parkinson's disease (PD) is a multifaceted disease characterized by degeneration of nigrostriatal dopaminergic neurons, which results in motor and non-motor dysfunctions. Accumulation of α-synuclein (αSYN) in Lewy bodies is a key pathological feature of PD. Although the exact cause of PD remains unknown, accumulating evidence suggests that brain infiltration of T cells plays a critical role in the pathogenesis of disease, contributing to neuroinflammation and dopaminergic neurodegeneration. Here, we used a mouse model of brain-infused aggregated αSYN, which recapitulates motor and non-motor dysfunctions seen in PD patients. We found that αSYN-induced motor dysfunction in mice is accompanied by an increased number of brain-residing Th17 (IL17+ CD4+) cells, but not CD8+ T cells. To evaluate whether the modulation of T cell response could rescue αSYN-induced damage, we chronically treated animals with abatacept (8 mg/kg, sc, 3x per week), a selective T-cell co-stimulation modulator. We found that abatacept treatment decreased Th1 (IFNƔ+ CD4+) and Th17 (IL17+ CD4+) cells in the brain, rescued motor function and prevented dopaminergic neuronal loss in αSYN-infused mice. These results highlight the significance of effector CD4+ T cells, especially Th17, in the progression of PD and introduce novel possibilities for repurposing immunomodulatory drugs used for arthritis as PD-modifying therapies.

3.
iScience ; 27(7): 110178, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38993676

RESUMO

Zika virus (ZIKV) is a neurotropic flavivirus that can persist in several tissues. The late consequences of ZIKV persistence and whether new rounds of active replication can occur, remain unaddressed. Here, we investigated whether neonatally ZIKV-infected mice are susceptible to viral reactivation in adulthood. We found that when ZIKV-infected mice are treated with immunosuppressant drugs, they present increased susceptibility to chemically induced seizures. Levels of subgenomic flavivirus RNAs (sfRNAs) were increased, relative to the amounts of genomic RNAs, in the brains of mice following immunosuppression and were associated with changes in cytokine expression. We investigated the impact of immunosuppression on the testicles and found that ZIKV genomic RNA levels are increased in mice following immunosuppression, which also caused significant testicular damage. These findings suggest that ZIKV can establish new rounds of active replication long after acute stages of disease, so exposed patients should be monitored to ensure complete viral eradication.

4.
Behav Brain Res ; 471: 115114, 2024 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-38878972

RESUMO

Zika virus (ZIKV) is a neurotropic Orthoflavivirus that causes a myriad of neurological manifestations in newborns exposed in uterus. Despite the devastating consequences of ZIKV on the developing brain, strategies to prevent or treat the consequences of viral infection are not yet available. We previously showed that short-term treatment with the TNF-α neutralizing monoclonal antibody. Infliximab could prevent seizures at acute and chronic stages of ZIKV infection, but had no impact on long-term cognitive and motor dysfunction. Due to the central role of inflammation in ZIKV-neuropathology, we hypothesized that prolonged treatment with the anti-TNF-α monoclonal antibody Infliximab could provide complete rescue of long-term behavioral deficits associated with neonatal ZIKV infection in mice. Here, neonatal (post-natal day 3) Swiss mice were submitted to subcutaneous (s.c.) injection of 106 PFU of ZIKV or mock medium and were then treated with Infliximab (20 µg/day) or sterile saline intraperitoneally (i.p.), for 40 days starting on the day of infection, and behavioral assessment started at 60 days post-infection (dpi). Infliximab prevented ZIKV-induced cognitive and motor impairments in mice. In addition, microgliosis and cell death found in mice following ZIKV infection were partially reversed by TNF-α blockage. Altogether, these results suggest that TNF-α-mediated inflammation is central for late ZIKV-induced behavioral deficits and cell death and strategies targeting this cytokine may be promising approaches to treat subjects exposed to the virus during development.


Assuntos
Modelos Animais de Doenças , Infliximab , Fator de Necrose Tumoral alfa , Infecção por Zika virus , Animais , Infecção por Zika virus/complicações , Camundongos , Infliximab/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Comportamento Animal/efeitos dos fármacos , Animais Recém-Nascidos , Zika virus/efeitos dos fármacos , Masculino , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/tratamento farmacológico , Feminino
5.
J Neurochem ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38934224

RESUMO

Gut dysbiosis is linked to metabolic and neurodegenerative diseases and comprises a plausible link between high-fat diet (HFD) and brain dysfunction. Here we show that gut microbiota modulation by either antibiotic treatment for 5 weeks or a brief 3-day fecal microbiota transplantation (FMT) regimen from low-fat (control) diet-fed mice decreased weight gain, adipose tissue hypertrophy, and glucose intolerance induced by HFD in C57BL/6 male mice. Notably, gut microbiota modulation by FMT completely reversed impaired recognition memory induced by HFD, whereas modulation by antibiotics had less pronounced effect. Improvement in recognition memory by FMT was accompanied by decreased HFD-induced astrogliosis in the hippocampal cornu ammonis region. Gut microbiome composition analysis indicated that HFD diminished microbiota diversity compared to control diet, whereas FMT partially restored the phyla diversity. Our findings reinforce the role of the gut microbiota on HFD-induced cognitive impairment and suggest that modulating the gut microbiota may be an effective strategy to prevent metabolic and cognitive dysfunction associated with unfavorable dietary patterns.

6.
Br J Pharmacol ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38936407

RESUMO

BACKGROUND AND PURPOSE: Inhibitors of histone deacetylases (iHDACs) are promising drugs for neurodegenerative diseases. We have evaluated the therapeutic potential of the new iHDAC LASSBio-1911 in Aß oligomer (AßO) toxicity models and astrocytes, key players in neuroinflammation and Alzheimer's disease (AD). EXPERIMENTAL APPROACH: Astrocyte phenotype and synapse density were evaluated by flow cytometry, Western blotting, immunofluorescence and qPCR, in vitro and in mice. Cognitive function was evaluated by behavioural assays using a mouse model of intracerebroventricular infusion of AßO. KEY RESULTS: LASSBio-1911 modulates reactivity and synaptogenic potential of cultured astrocytes and improves synaptic markers in cultured neurons and in mice. It prevents AßO-triggered astrocytic reactivity in mice and enhances the neuroprotective potential of astrocytes. LASSBio-1911 improves behavioural performance and rescues synaptic and memory function in AßO-infused mice. CONCLUSION AND IMPLICATIONS: These results contribute to unveiling the mechanisms underlying astrocyte role in AD and provide the rationale for using astrocytes as targets to new drugs for AD.

7.
An Acad Bras Cienc ; 96(2): e20231068, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38865558

RESUMO

Open access (OA) publishing provides free online access to research articles without subscription fees. In Brazil, absence of financial support from academic institutions and limited government policies pose challenges to OA publication. Here, we used data from the Web of Science and Scopus to compare with global trends in journal accessibility and scientific quality metrics. Brazilian authors publish more OA articles, particularly in Global South journals. While OA correlates with quality for global authors, it had no impact on Brazilian science. To maximize impact, Brazilian authors should prioritize Q1 journals regardless of OA status. High-impact or Global North journal publication seems more relevant for Brazilian science than OA. Our findings indicate that the present open access policy has been ineffective to improve the impact of Brazilian science, providing insights to guide the formulation of scientific public policies.


Assuntos
Publicação de Acesso Aberto , Publicações Periódicas como Assunto , Brasil , Publicação de Acesso Aberto/tendências , Publicação de Acesso Aberto/economia , Publicações Periódicas como Assunto/tendências , Publicações Periódicas como Assunto/estatística & dados numéricos , Humanos , Bibliometria , Fator de Impacto de Revistas , Acesso à Informação , Editoração/tendências , Editoração/estatística & dados numéricos
8.
Mol Psychiatry ; 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678084

RESUMO

It is well known the potential of severe acute respiratory coronavirus type 2 (SARS-CoV-2) infection to induce post-acute sequelae, a condition called Long COVID. This syndrome includes several symptoms, but the central nervous system (CNS) main one is neurocognitive dysfunction. Recently it has been demonstrated the relevance of plasma levels of neurofilament light chain (pNfL), as a biomarker of early involvement of the CNS in COVID-19. The aim of this study was to investigate the relationship between pNfL in patients with post-acute neurocognitive symptoms and the potential of NfL as a prognostic biomarker in these cases. A group of 63 long COVID patients ranging from 18 to 59 years-old were evaluated, submitted to a neurocognitive battery assessment, and subdivided in different groups, according to results. Plasma samples were collected during the long COVID assessment and used for measurement of pNfL with the Single molecule array (SIMOA) assays. Levels of pNfL were significantly higher in long COVID patients with neurocognitive symptoms when compared to HC (p = 0.0031). Long COVID patients with cognitive impairment and fatigue symptoms presented higher pNfL levels when compared to long COVID patients without these symptoms, individually and combined (p = 0.0263, p = 0.0480, and 0.0142, respectively). Correlation analysis showed that levels of cognitive lost and exacerbation of fatigue in the neurocognitive evaluation had a significative correlation with higher pNfL levels (p = 0.0219 and 0.0255, respectively). Previous reports suggested that pNfL levels are related with higher risk of severity and predict lethality of COVID-19. Our findings demonstrate that SARS-CoV-2 infection seems to have a long-term impact on the brain, even in patients who presented mild acute disease. NfL measurements might be useful to identify CNS involvement in long COVID associated with neurocognitive symptoms and to identify who will need continuous monitoring and treatment support.

9.
Brain Behav Immun ; 118: 318-333, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38460804

RESUMO

Zika virus (ZIKV), the causative agent of Zika fever, is a flavivirus transmitted by mosquitoes of the Aedes genus. Zika virus infection has become an international concern due to its association with severe neurological complications such as fetal microcephaly. Viral infection can induce the release of ATP in the extracellular environment, activating receptors sensitized by extracellular nucleotides, such as the P2X7 receptor. This receptor is the primary purinergic receptor involved in neuroinflammation, neurodegeneration, and immunity. In this work, we investigated the role of ATP-P2X7 receptor signaling in Zika-related brain abnormalities. Wild-type mice (WT) and P2X7 receptor-deficient (P2X7-/-) C57BL/6 newborn mice were subcutaneously inoculated with 5 × 106plaque-forming units of ZIKV or mock solution. P2X7 receptor expression increased in the brain of Zika virus-infected mice compared to the mock group. Comparative analyses of the hippocampi from WT and P2X7-/-mice revealed that the P2X7 receptor increased hippocampal damage in CA1/CA2 and CA3 regions. Doublecortin expression decreased significantly in the brains of ZIKV-infected mice. WT ZIKV-infected mice showed impaired motor performance compared to P2X7-/- infected mice. WT ZIKV-infected animals showed increased expression of glial markers GFAP (astrocytes) and IBA-1 (microglia) compared to P2X7-/- infected mice. Although the P2X7 receptor contributes to neuronal loss and neuroinflammation, WT mice were more efficient in controlling the viral load in the brain than P2X7 receptor-deficient mice. This result was associated with higher induction of TNF-α, IFN-ß, and increased interferon-stimulated gene expression in WT mice than P2X7-/-ZIKV-infected. Finally, we found that the P2X7 receptor contributes to inhibiting the neuroprotective signaling pathway AKT/mTOR while stimulating the caspase-3 activation, possibly two distinct pathways contributing to neurodegeneration. These findings suggest that ATP-P2X7 receptor signaling contributes to the antiviral response in the brain of ZIKV-infected mice while increasing neuronal loss, neuroinflammation, and related brain abnormalities.


Assuntos
Infecção por Zika virus , Zika virus , Gravidez , Feminino , Animais , Camundongos , Zika virus/genética , Doenças Neuroinflamatórias , Receptores Purinérgicos P2X7/genética , Receptores Purinérgicos P2X7/metabolismo , Camundongos Endogâmicos C57BL , Encéfalo/metabolismo , Transdução de Sinais , Trifosfato de Adenosina
10.
Biochim Biophys Acta Mol Basis Dis ; 1870(5): 167097, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38408544

RESUMO

Zika virus (ZIKV) infection was first associated with Central Nervous System (CNS) infections in Brazil in 2015, correlated with an increased number of newborns with microcephaly, which ended up characterizing the Congenital Zika Syndrome (CZS). Here, we investigated the impact of ZIKV infection on the functionality of iPSC-derived astrocytes. Besides, we extrapolated our findings to a Brazilian cohort of 136 CZS children and validated our results using a mouse model. Interestingly, ZIKV infection in neuroprogenitor cells compromises cell migration and causes apoptosis but does not interfere in astrocyte generation. Moreover, infected astrocytes lost their ability to uptake glutamate while expressing more glutamate transporters and secreted higher levels of IL-6. Besides, infected astrocytes secreted factors that impaired neuronal synaptogenesis. Since these biological endophenotypes were already related to Autism Spectrum Disorder (ASD), we extrapolated these results to a cohort of children, now 6-7 years old, and found seven children with ASD diagnosis (5.14 %). Additionally, mice infected by ZIKV revealed autistic-like behaviors, with a significant increase of IL-6 mRNA levels in the brain. Considering these evidence, we inferred that ZIKV infection during pregnancy might lead to synaptogenesis impairment and neuroinflammation, which could increase the risk for ASD.


Assuntos
Astrócitos , Transtorno do Espectro Autista , Doenças Neuroinflamatórias , Sinapses , Infecção por Zika virus , Zika virus , Infecção por Zika virus/patologia , Infecção por Zika virus/metabolismo , Infecção por Zika virus/virologia , Infecção por Zika virus/complicações , Transtorno do Espectro Autista/virologia , Transtorno do Espectro Autista/metabolismo , Transtorno do Espectro Autista/etiologia , Transtorno do Espectro Autista/patologia , Humanos , Animais , Camundongos , Zika virus/fisiologia , Feminino , Criança , Sinapses/metabolismo , Sinapses/patologia , Doenças Neuroinflamatórias/virologia , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/patologia , Doenças Neuroinflamatórias/etiologia , Astrócitos/virologia , Astrócitos/metabolismo , Astrócitos/patologia , Masculino , Interleucina-6/metabolismo , Interleucina-6/genética , Gravidez , Fatores de Risco , Células-Tronco Pluripotentes Induzidas/virologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Brasil/epidemiologia , Modelos Animais de Doenças , Neurogênese
11.
Neuropharmacology ; 245: 109828, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38158014

RESUMO

Oxaliplatin (OXA) is an antineoplastic agent used for the treatment of cisplatin-resistant tumours, presenting lower incidence of nephrotoxicity and myelotoxicity than other platinum-based drugs. However, OXA treatment is highly associated with painful peripheral neuropathy, a well-known and relevant side effect caused by mitochondrial dysfunction. The transfer of functional exogenous mitochondria (mitotherapy) is a promising therapeutic strategy for mitochondrial diseases. We investigated the effect of mitotherapy on oxaliplatin-induced painful peripheral neuropathy (OIPN) in male mice. OIPN was induced by i.p. injections of oxaliplatin (3 mg/kg) over 5 consecutive days. Mechanical (von Frey test) and cold (acetone drop test) allodynia were evaluated between 7 and 17 days after the first OXA treatment. Mitochondria was isolated from donor mouse livers and mitochondrial oxidative phosphorylation was assessed with high resolution respirometry. After confirming that the isolated mitochondria were functional, the organelles were administered at the dose of 0.5 mg/kg of mitochondrial protein on days 1, 3 and 5. Treatment with OXA caused both mechanical and cold allodynia in mice that were significant 7 days after the initial injection of OXA and persisted for up to 17 days. Mitotherapy significantly prevented the development of both sensory alterations, and attenuated body weight loss induced by OXA. Mitotherapy also prevented spinal cord ERK1/2 activation, microgliosis and the increase in TLR4 mRNA levels. Mitotherapy prevented OIPN by inhibiting neuroinflammation and the consequent cellular overactivity in the spinal cord, presenting a potential therapeutic strategy for pain management in oncologic patients undergoing OXA treatment.


Assuntos
Antineoplásicos , Dor , Doenças do Sistema Nervoso Periférico , Humanos , Masculino , Camundongos , Animais , Oxaliplatina/toxicidade , Hiperalgesia/induzido quimicamente , Hiperalgesia/prevenção & controle , Hiperalgesia/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/prevenção & controle , Antineoplásicos/toxicidade
12.
Mol Neurobiol ; 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37996731

RESUMO

Few studies showed that neurofilament light chain (NfL), glial fibrillary acidic protein (GFAP), total tubulin-associated unit (TAU), and ubiquitin carboxy-terminal hydrolase-L1 (UCH-L1) may be related to neurological manifestations and severity during and after SARS-CoV-2 infection. The objective of this work was to investigate the relationship among nervous system biomarkers (NfL, TAU, GFAP, and UCH-L1), biochemical parameters, and viral loads with heterogeneous outcomes in a cohort of severe COVID-19 patients admitted in Intensive Care Unit (ICU) of a university hospital. For that, 108 subjects were recruited within the first 5 days at ICU. In parallel, 16 mild COVID-19 patients were enrolled. Severe COVID-19 group was divided between "deceased" and "survivor." All subjects were positive for SARS-CoV-2 detection. NfL, total TAU, GFAP, and UCH-L1 quantification in plasma was performed using SIMOA SR-X platform. Of 108 severe patients, 36 (33.33%) presented neurological manifestation and 41 (37.96%) died. All four biomarkers - GFAP, NfL, TAU, and UCH-L1 - were significantly higher among deceased patients in comparison to survivors (p < 0.05). Analyzing biochemical biomarkers, higher Peak Serum Ferritin, D-Dimer Peak, Gamma-glutamyltransferase, and C-Reactive Protein levels were related to death (p < 0.0001). In multivariate analysis, GFAP, NfL, TAU, UCH-L1, and Peak Serum Ferritin levels were correlated to death. Regarding SARS-CoV-2 viral load, no statistical difference was observed for any group. Thus, Ferritin, NFL, GFAP, TAU, and UCH-L1 are early biomarkers of severity and lethality of SARS-COV-2 infection and may be important tools for therapeutic decision-making in the acute phase of disease.

13.
Behav Brain Res ; 451: 114519, 2023 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-37263423

RESUMO

Zika virus (ZIKV) infection causes severe neurological consequences in both gestationally-exposed infants and adults. Sensorial gating deficits strongly correlate to the motor, sensorial and cognitive impairments observed in ZIKV-infected patients. However, no startle response or prepulse inhibition (PPI) assessment has been made in patients or animal models. In this study, we identified different outcomes according to the age of infection and sex in mice: neonatally infected animals presented an increase in PPI and delayed startle latency. However, adult-infected male mice presented lower startle amplitude, while a PPI impairment was observed 14 days after infection in both sexes. Our data further the understanding of the functional impacts of ZIKV on the developing and mature nervous system, which could help explain other behavioral and cognitive alterations caused by the virus. With this study, we support the startle reflex testing in ZIKV-exposed patients, especially infants, allowing for early detection of functional neuromotor damage and early intervention.


Assuntos
Infecção por Zika virus , Zika virus , Feminino , Masculino , Animais , Camundongos , Reflexo de Sobressalto/fisiologia , Inibição Pré-Pulso , Infecção por Zika virus/complicações , Estimulação Acústica
14.
Front Pharmacol ; 14: 1179723, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37153798

RESUMO

Introduction: Sepsis is defined as a multifactorial debilitating condition with high risks of death. The intense inflammatory response causes deleterious effects on the brain, a condition called sepsis-associated encephalopathy. Neuroinflammation or pathogen recognition are able to stress cells, resulting in ATP (Adenosine Triphosphate) release and P2X7 receptor activation, which is abundantly expressed in the brain. The P2X7 receptor contributes to chronic neurodegenerative and neuroinflammatory diseases; however, its function in long-term neurological impairment caused by sepsis remains unclear. Therefore, we sought to evaluate the effects of P2X7 receptor activation in neuroinflammatory and behavioral changes in sepsis-surviving mice. Methods: Sepsis was induced in wild-type (WT), P2X7-/-, and BBG (Brilliant Blue G)-treated mice by cecal ligation and perforation (CLP). On the thirteenth day after the surgery, the cognitive function of mice was assessed using the novel recognition object and Water T-maze tests. Acetylcholinesterase (AChE) activity, microglial and astrocytic activation markers, and cytokine production were also evaluated. Results: Initially, we observed that both WT and P2X7-/- sepsis-surviving mice showed memory impairment 13 days after surgery, once they did not differentiate between novel and familiar objects. Both groups of animals presented increased AChE activity in the hippocampus and cerebral cortex. However, the absence of P2X7 prevented partly this increase in the cerebral cortex. Likewise, P2X7 absence decreased ionized calcium-binding protein 1 (Iba-1) and glial fibrillary acidic protein (GFAP) upregulation in the cerebral cortex of sepsis-surviving animals. There was an increase in GFAP protein levels in the cerebral cortex but not in the hippocampus of both WT and P2X7-/- sepsis-surviving animals. Pharmacological inhibition or genetic deletion of P2X7 receptor attenuated the production of Interleukin-1ß (IL-1ß), Tumor necrosis factor-α (TNF-α), and Interleukin-10 (IL-10). Conclusion: The modulation of the P2X7 receptor in sepsis-surviving animals may reduce neuroinflammation and prevent cognitive impairment due to sepsis-associated encephalopathy, being considered an important therapeutic target.

15.
Front Immunol ; 14: 1158460, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37114062

RESUMO

Despite long-term sequelae of COVID-19 are emerging as a substantial public health concern, the mechanism underlying these processes still unclear. Evidence demonstrates that SARS-CoV-2 Spike protein can reach different brain regions, irrespective of viral brain replication resulting in activation of pattern recognition receptors (PRRs) and neuroinflammation. Considering that microglia dysfunction, which is regulated by a whole array of purinergic receptors, may be a central event in COVID-19 neuropathology, we investigated the impact of SARS-CoV-2 Spike protein on microglial purinergic signaling. Here, we demonstrate that cultured microglial cells (BV2 line) exposed to Spike protein induce ATP secretion and upregulation of P2Y6, P2Y12, NTPDase2 and NTPDase3 transcripts. Also, immunocytochemistry analysis shows that spike protein increases the expression of P2X7, P2Y1, P2Y6, and P2Y12 in BV2 cells. Additional, hippocampal tissue of Spike infused animals (6,5ug/site, i.c.v.) presents increased mRNA levels of P2X7, P2Y1, P2Y6, P2Y12, NTPDase1, and NTPDase2. Immunohistochemistry experiments confirmed high expression of the P2X7 receptor in microglial cells in CA3/DG hippocampal regions after spike infusion. These findings suggest that SARS-CoV-2 Spike protein modulates microglial purinergic signaling and opens new avenues for investigating the potential of purinergic receptors to mitigate COVID-19 consequences.


Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Animais , Humanos , Glicoproteína da Espícula de Coronavírus/metabolismo , Microglia/metabolismo , COVID-19/metabolismo , SARS-CoV-2
17.
Cell Rep ; 42(3): 112189, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36857178

RESUMO

Cognitive dysfunction is often reported in patients with post-coronavirus disease 2019 (COVID-19) syndrome, but its underlying mechanisms are not completely understood. Evidence suggests that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Spike protein or its fragments are released from cells during infection, reaching different tissues, including the CNS, irrespective of the presence of the viral RNA. Here, we demonstrate that brain infusion of Spike protein in mice has a late impact on cognitive function, recapitulating post-COVID-19 syndrome. We also show that neuroinflammation and hippocampal microgliosis mediate Spike-induced memory dysfunction via complement-dependent engulfment of synapses. Genetic or pharmacological blockage of Toll-like receptor 4 (TLR4) signaling protects animals against synapse elimination and memory dysfunction induced by Spike brain infusion. Accordingly, in a cohort of 86 patients who recovered from mild COVID-19, the genotype GG TLR4-2604G>A (rs10759931) is associated with poor cognitive outcome. These results identify TLR4 as a key target to investigate the long-term cognitive dysfunction after COVID-19 infection in humans and rodents.


Assuntos
COVID-19 , Disfunção Cognitiva , Humanos , Animais , Camundongos , COVID-19/complicações , Glicoproteína da Espícula de Coronavírus/genética , SARS-CoV-2/metabolismo , Receptor 4 Toll-Like , Síndrome de COVID-19 Pós-Aguda
18.
Homeopatia Méx ; (n.esp): 123-128, feb. 2023.
Artigo em Espanhol | LILACS, HomeoIndex - Homeopatia | ID: biblio-1416733

RESUMO

La eficacia y seguridad del tratamiento homeopático fueron investigadas en niños con amigdalitis recurrente para la que se indicaba cirugía. Métodos: Estudio clínico prospectivo, aleatorizado, doble ciego, que incluyó 40 niños de entre 3 y 7 años de edad; 20 niños fueron tratados con medicación homeopática y otros 20 niños, con placebo. El seguimiento fue de 4 meses por niño. La evaluación de los resultados fue clínica mediante un cuestionario estándar y examen clínico el primer y último día de tratamiento. La amigdalitis recurrente se definió como ocurrencia de 5 a 7 episodios de amigdalitis bacteriana aguda al año. Resultados: Del grupo de 18 niños que completó el tratamiento homeopático, 14 no presentó episodio alguno de amigdalitis bacteriana aguda; del grupo de 15 niños que recibió placebo, 5 pacientes no presentaron amigdalitis. Esta diferencia fue estadísticamente significativa (p = 0,015). Ninguno de los pacientes presentó efectos secundarios. Conclusiones: El tratamiento homeopático fue efectivo en niños con amigdalitis recurrente, en comparación con el placebo; a 14 niños (78%) ya no se les indicó cirugía. El tratamiento homeopático no se asoció con eventos adversos.


The efficacy and safety of homeopathic treatment was investigated on children with recurrent tonsillitis justifying surgery. Methods: Prospective, randomized,double-blind clinical trial that included 40 children between ages of 3 to 7 years old;20 children were treated with homeopathic medication and 20 children with placebo. Follow up was 4 months per child. Assessment of results was clinical by means of a standard questionnaire and clinical examination on the first and last day of treatment.Recurrent tonsillitis was defined as 5 to 7 episodes of bacterial acute tonsillitis per year. Results: From the group of 18 children who completed homeopathic treatment, 14 did not present any episode of acute bacterial tonsillitis; from the group of 15 children whoreceived placebo 5 patients did not present tonsillitis; this difference was statistically significant (p= 0,015). None of the patient exhibited side effects. Conclusions: Homeopathic treatment was effective in children with recurrent tonsillitis compared to placebo, 14 children (78%) were no longer indicated surgery. Homeopathic treatment was not associated with adverse events.


Assuntos
Humanos , Pré-Escolar , Criança , Tonsilite/tratamento farmacológico , Medicamento Homeopático , Método Duplo-Cego
19.
Mater Today Bio ; 18: 100525, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36619201

RESUMO

Several human pathogens can cause long-lasting neurological damage. Despite the increasing clinical knowledge about these conditions, most still lack efficient therapeutic interventions. Gene therapy (GT) approaches comprise strategies to modify or adjust the expression or function of a gene, thus providing therapy for human diseases. Since recombinant nucleic acids used in GT have physicochemical limitations and can fail to reach the desired tissue, viral and non-viral vectors are applied to mediate gene delivery. Although viral vectors are associated to high levels of transfection, non-viral vectors are safer and have been further explored. Different types of nanosystems consisting of lipids, polymeric and inorganic materials are applied as non-viral vectors. In this review, we discuss potential targets for GT intervention in order to prevent neurological damage associated to infectious diseases as well as the role of nanosized non-viral vectors as agents to help the selective delivery of these gene-modifying molecules. Application of non-viral vectors for delivery of GT effectors comprise a promising alternative to treat brain inflammation induced by viral infections.

20.
Int J Mol Sci ; 23(20)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36292931

RESUMO

The Wnt/ß-catenin signaling pathway dictates cell proliferation and differentiation during embryonic development and tissue homeostasis. Its deregulation is associated with many pathological conditions, including neurodegenerative disease, frequently downregulated. The lack of efficient treatment for these diseases, including Alzheimer's disease (AD), makes Wnt signaling an attractive target for therapies. Interestingly, novel Wnt signaling activating compounds are less frequently described than inhibitors, turning the quest for novel positive modulators even more appealing. In that sense, natural compounds are an outstanding source of potential drug leads. Here, we combine different experimental models, cell-based approaches, neuronal culture assays, and rodent behavior tests with Xenopus laevis phenotypic analysis to characterize quercitrin, a natural compound, as a novel Wnt signaling potentiator. We find that quercitrin potentiates the signaling in a concentration-dependent manner and increases the occurrence of the Xenopus secondary axis phenotype mediated by Xwnt8 injection. Using a GSK3 biosensor, we describe that quercitrin impairs GSK3 activity and increases phosphorylated GSK3ß S9 levels. Treatment with XAV939, an inhibitor downstream of GSK3, impairs the quercitrin-mediated effect. Next, we show that quercitrin potentiates the Wnt3a-synaptogenic effect in hippocampal neurons in culture, which is blocked by XAV939. Quercitrin treatment also rescues the hippocampal synapse loss induced by intracerebroventricular injection of amyloid-ß oligomers (AßO) in mice. Finally, quercitrin rescues AßO-mediated memory impairment, which is prevented by XAV939. Thus, our study uncovers a novel function for quercitrin as a Wnt/ß-catenin signaling potentiator, describes its mechanism of action, and opens new avenues for AD treatments.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Camundongos , Animais , Via de Sinalização Wnt , Peptídeos beta-Amiloides/farmacologia , beta Catenina/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Doença de Alzheimer/patologia , Quercetina/farmacologia , Quercetina/uso terapêutico
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