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1.
J Appl Microbiol ; 135(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38444193

RESUMO

AIM: This study aimed to compare and characterize the resistance profile and the presence of extended-spectrum beta-lactamase (ESBL) related genes in Escherichia coli isolated from healthy finishing pigs fed with or without antibiotics in their diets. METHODS AND RESULTS: A total of 27 ceftiofur-resistant E. coli isolates were obtained from 96 healthy pigs. The antibiotic resistance profile was tested, and all 27 isolates were classified as multidrug-resistant (MDR). A high proportion of isolates were resistant to cephalosporins, ampicillin, ciprofloxacin, and tetracyclines. The ESBL production was observed in 85% of isolates by double-disc synergy test. The MDR-E. coli isolates harbored ESBL genes, such as blaTEM, blaCTX-M-1, blaCTX-M-2, and blaCTX-M-8,25. In addition, other antibiotics resistance genes (ARGs) were also detected, such as sul2, ant(3″)-I, tetA, and mcr-1. The mobilization of the blaCTX-M gene was confirmed for nine E. coli isolates by conjugation assays. The presence of blaCTX-M on mobile genetic elements in these isolates was demonstrated by Southern blot hybridization, and the resistance to cephalosporins was confirmed in the transconjugants. Our results indicate the prevalence of CTX-M-producing E. coli strains harboring mobile genetic elements in the normal microbiota of healthy pigs. CONCLUSIONS: These findings highlight the significance of ESBL genes as a global health concern in livestock and the potential spread of antimicrobial resistance to other members of the gastrointestinal tract microbiota.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Animais , Suínos , Gado , Prevalência , beta-Lactamases/genética , beta-Lactamases/metabolismo , Cefalosporinas/farmacologia , Antibacterianos/farmacologia , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/veterinária , Farmacorresistência Bacteriana Múltipla/genética , Plasmídeos
2.
NMR Biomed ; 37(5): e5108, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38273732

RESUMO

Functional MRI (fMRI) and MRS (fMRS) can be used to noninvasively map cerebral activation and metabolism. Recently, hyperpolarized 13C spectroscopy and metabolic imaging have provided an alternative approach to assess metabolism. In this study, we combined 1H fMRI and hyperpolarized [1-13C]pyruvate MRS to compare cerebral blood oxygenation level-dependent (BOLD) response and real-time cerebral metabolism, as assessed with lactate and bicarbonate labelling, during nicotine stimulation. Simultaneous 1H fMRI (multislice gradient echo echo-planar imaging) and 13C spectroscopic (single slice pulse-acquire) data were collected in urethane-anaesthetized female Sprague-Dawley rats (n = 12) at 9.4 T. Animals received an intravenous (i.v.) injection of either nicotine (stimulus; 88 µg/kg, n = 7, or 300 µg/kg, n = 5) or 0.9% saline (matching volume), followed by hyperpolarized [1-13C]pyruvate injection 60 s later. Three hours later, a second injection was administered: the animals that had previously received saline were injected with nicotine and vice versa, both followed by another hyperpolarized [1-13C]pyruvate i.v. injection 60 s later. The low-dose (88 µg/kg) nicotine injection led to a 12% ± 4% (n = 7, t-test, p ~ 0.0006 (t-value -5.8, degrees of freedom 6), Wilcoxon p ~ 0.0078 (test statistic 0)) increase in BOLD signal. At the same time, an increase in 13C-bicarbonate signal was seen in four out of six animals. Bicarbonate-to-total carbon ratios were 0.010 ± 0.004 and 0.018 ± 0.010 (n = 6, t-test, p ~ 0.03 (t-value -2.3, degrees of freedom 5), Wilcoxon p ~ 0.08 (test statistic 3)) for saline and nicotine experiments, respectively. No increase in the lactate signal was seen; lactate-to-total carbon was 0.16 ± 0.02 after both injections. The high (300 µg/kg) nicotine dose (n = 5) caused highly variable BOLD and metabolic responses, possibly due to the apparent respiratory distress. Simultaneous detection of 1H fMRI and hyperpolarized 13C-MRS is feasible. A comparison of metabolic response between control and stimulated states showed differences in bicarbonate signal, implying that the hyperpolarization technique could offer complimentary information on brain activation.


Assuntos
Imageamento por Ressonância Magnética , Ácido Pirúvico , Ratos , Feminino , Animais , Imageamento por Ressonância Magnética/métodos , Ácido Pirúvico/metabolismo , Nicotina/farmacologia , Ratos Sprague-Dawley , Bicarbonatos/metabolismo , Isótopos de Carbono/metabolismo , Ácido Láctico/metabolismo
3.
Front Microbiol ; 14: 1291930, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38075857

RESUMO

Extracellular vesicle (EV) production by bacteria is an important mechanism for microbial communication and host-pathogen interaction. EVs of some bacterial species have been reported to contain nucleic acids. However, the role of small RNAs (sRNAs) packaged in EVs is poorly understood. Here, we report on the RNA cargo of EVs produced by the pig pathogen Actinobacillus pleuropneumoniae, the causal agent of porcine pleuropneumonia, a disease which causes substantial economic losses to the swine industry worldwide. The EVs produced by aerobically and anaerobically grown bacteria were only slightly different in size and distribution. Total cell and outer membrane protein profiles and lipid composition of A. pleuropneumoniae whole cell extracts and EVs were similar, although EVs contained rough lipopolysaccharide compared to the smooth form in whole cells. Approximately 50% of Galleria mellonella larvae died after the injection of EVs. RNAseq, RT-PCR, protection from nuclease degradation, and database searching identified previously described and 13 novel A. pleuropneumoniae sRNAs in EVs, some of which were enriched compared to whole cell content. We conclude that A. pleuropneumoniae EVs contain sRNAs, including those known to be involved in virulence, and some with homologs in other Pasteurellaceae and/or non-Pasteurellaceae. Further work will establish whether the novel sRNAs in A. pleuropneumoniae EVs play any role in pathogenesis.

4.
Int J Mol Sci ; 24(22)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38003438

RESUMO

Rett Syndrome is an X-linked neurodevelopmental disorder (RTT; OMIM#312750) associated to MECP2 mutations. MeCP2 dysfunction is seen as one cause for the deficiencies found in brain-derived neurotrophic factor (BDNF) signaling, since BDNF is one of the genes under MeCP2 jurisdiction. BDNF signaling is also dependent on the proper function of the adenosinergic system. Indeed, both BDNF signaling and the adenosinergic system are altered in Mecp2-null mice (Mecp2-/y), a representative model of severe manifestation of RTT. Considering that symptoms severity largely differs among RTT patients, we set out to investigate the BDNF and ADO signaling modifications in Mecp2 heterozygous female mice (Mecp2+/-) presenting a less severe phenotype. Symptomatic Mecp2+/- mice have lower BDNF levels in the cortex and hippocampus. This is accompanied by a loss of BDNF-induced facilitation of hippocampal long-term potentiation (LTP), which could be restored upon selective activation of adenosine A2A receptors (A2AR). While no differences were observed in the amount of adenosine in the cortex and hippocampus of Mecp2+/- mice compared with healthy littermates, the density of the A1R and A2AR subtype receptors was, respectively, upregulated and downregulated in the hippocampus. Data suggest that significant changes in BDNF and adenosine signaling pathways are present in an RTT model with a milder disease phenotype: Mecp2+/- female animals. These features strengthen the theory that boosting adenosinergic activity may be a valid therapeutic strategy for RTT patients, regardless of their genetic penetrance.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Síndrome de Rett , Animais , Feminino , Humanos , Camundongos , Adenosina/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Estudos Transversais , Modelos Animais de Doenças , Proteína 2 de Ligação a Metil-CpG/genética , Proteína 2 de Ligação a Metil-CpG/metabolismo , Camundongos Knockout , Síndrome de Rett/metabolismo
5.
Am J Public Health ; 113(12): 1263-1266, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37797279

RESUMO

Racial/ethnic disparities in the administration of mpox vaccine in Fulton County, Georgia, threatened to undermine the effectiveness of the response. To counteract this inequity, the Fulton County Board of Health partnered with local agencies serving Black and Latino men who have sex with men to coordinate efforts and reserve blocks of time for clients of these agencies to receive a vaccine. The disparities were reversed and approached equity with case rates. (Am J Public Health. 2023;113(12):1263-1266. https://doi.org/10.2105/AJPH.2023.307416).


Assuntos
Disparidades em Assistência à Saúde , Mpox , Vacina Antivariólica , Humanos , Masculino , Georgia , Hispânico ou Latino , Grupos Raciais , Mpox/prevenção & controle , Negro ou Afro-Americano
6.
Chemphyschem ; 24(19): e202300100, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37431722

RESUMO

This paper reports the synthesis, characterization and in vivo application of water-soluble supramolecular contrast agents (Mw: 5-5.6 kDa) for MRI obtained from ß-cyclodextrin functionalized with different kinds of nitroxide radicals, both with piperidine structure (CD2 and CD3) and with pyrrolidine structure (CD4 and CD5). As to the stability of the radicals in presence of ascorbic acid, CD4 and CD5 have low second order kinetic constants (≤0.05 M-1 s-1 ) compared to CD2 (3.5 M-1 s-1 ) and CD3 (0.73 M-1 s-1 ). Relaxivity (r1 ) measurements on compounds CD3-CD5 were carried out at different magnetic field strength (0.7, 3, 7 and 9.4 T). At 0.7 T, r1 values comprised between 1.5 mM-1 s-1 and 1.9 mM-1 s-1 were found while a significant reduction was observed at higher fields (r1 ≈0.6-0.9 mM-1 s-1 at 9.4 T). Tests in vitro on HEK293 human embryonic kidney cells, L929 mouse fibroblasts and U87 glioblastoma cells indicated that all compounds were non-cytotoxic at concentrations below 1 µmol mL-1 . MRI in vivo was carried out at 9.4 T on glioma-bearing rats using the compounds CD3-CD5. The experiments showed a good lowering of T1 relaxation in tumor with a retention of the contrast for at least 60 mins confirming improved stability also in vivo conditions.


Assuntos
Meios de Contraste , Ciclodextrinas , Camundongos , Ratos , Humanos , Animais , Meios de Contraste/toxicidade , Meios de Contraste/química , Células HEK293 , Imageamento por Ressonância Magnética/métodos , Oxirredução
7.
Int J Clin Pediatr Dent ; 16(1): 147-152, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37020764

RESUMO

Hartsfield syndrome is a rare and unique clinical combination of ectrodactyly and holoprosencephaly (HPE) with or without cleft lip and palate, as well as various additional characteristics. Although several genes responsible for HPE and ectrodactyly have been identified, the genetic origin of Hartsfield syndrome remains unknown, as there are few reports in the literature. The objective of this case report is to present dentofacial abnormalities in an 11-year-old boy with Hartsfield syndrome, who presented mental retardation, hearing loss, bilateral hand and foot ectrodactyly, HPE, and solitary median maxillary central incisor (SMMCI) besides 12 dental ageneses. How to cite this article: P Reis PM, Faber J, O Rosa JS, et al. Solitary Median Maxillary Central Incisor in Hartsfield Syndrome: A Case Report. Int J Clin Pediatr Dent 2023;16(1):147-152.

8.
Naunyn Schmiedebergs Arch Pharmacol ; 396(7): 1535-1545, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36790483

RESUMO

Morphine is among the most powerful analgesics and pain-relieving agents. However, its addictive properties limit their medical use because patients may be susceptible to abuse and reinstatement. Morphine addiction occurs because of dopamine release in the mesolimbic brain area, implying in an increase in oxidative stress. Ferulic acid (FA), a phenolic phytochemical found in a variety of foods, has been reported to exert antioxidant and neuroprotective effects; however, its low bioavailability makes its nano-encapsulated form a promising alternative. This study aimed to evaluate the protective effects of a novel nanosystem with FA on morphine reinstatement and the consequent molecular neuroadaptations and oxidative status in the mesolimbic region. Rats previously exposed to morphine in conditioned place preference (CPP) paradigm were treated with ferulic acid-loaded nanocapsules (FA-Nc) or nonencapsulated FA during morphine-preference extinction. Following the treatments, animals were re-exposed to morphine to induce the reinstatement. While morphine-preference extinction was comparable among all experimental groups, FA-Nc treatment prevented morphine reinstatement. In the dorsal striatum, while morphine exposure increased lipid peroxidation (LP) and reactive species (RS), FA-Nc decreased LP and FA decreased RS levels. Morphine exposure increased the dopaminergic markers (D1R, D3R, DAT) and ΔFosB immunoreactivity in the ventral striatum; however, FA-Nc treatment decreased D1R, D3R, and ΔFosB and increased D2R, DAT, and NRF2. In conclusion, FA-Nc treatment prevented the morphine reinstatement, promoted antioxidant activity, and modified the dopaminergic neurotransmission, NRF2, and ΔFosB, what may indicate a neuroprotective and antioxidant role of this nanoformulation.


Assuntos
Dopamina , Morfina , Ratos , Animais , Morfina/farmacologia , Fator 2 Relacionado a NF-E2 , Antioxidantes/farmacologia , Encéfalo
9.
Behav Brain Res ; 437: 114129, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36179804

RESUMO

Evidence has demonstrated the hippocampal cholinergic system and the mammalian target of rapamycin (mTOR) participation during the memory formation of aversive events. This study assessed the role of these systems in the hippocampus for the extinction memory process by submitting male Wistar rats to fear-motivated step-down inhibitory avoidance (IA). The post-extinction session administration of the nicotinic and muscarinic cholinergic receptor antagonists, mecamylamine and scopolamine, respectively, both at doses of 2 µg/µl/side, and rapamycin, an mTOR inhibitor (0.02 µg/µl/side), into the CA1 region of the dorsal hippocampus, impaired the IA extinction memory. Furthermore, the nicotinic and muscarinic cholinergic receptor agonists, nicotine and muscarine, respectively, had a dose-dependent effect on the IA extinction memory when administered intra-CA1, immediately after the extinction session. Nicotine (0.6 µg/µl/side) and muscarine (0.02 µg/µl/side), respectively, had no effect, while the higher doses (6 and 2 µg/µl/side, respectively) impaired the IA extinction memory. Interestingly, the co-administration of muscarine at the lower dose blocked the impairment that was induced by rapamycin. This effect was not observed when nicotine at the lower dose was co-administered. These results have demonstrated the participation of the cholinergic receptors and mTOR in the hippocampus for IA extinction, and that the cholinergic agonists had a dose-dependent effect on the IA extinction memory. This study provides insights related to the behavioural aspects and the neurobiological properties underlying the early stage of fear-motivated IA extinction memory consolidation and suggests that there is hippocampal muscarinic receptor participation independent of mTOR in this memory process.


Assuntos
Aprendizagem da Esquiva , Extinção Psicológica , Medo , Hipocampo , Memória , Receptores Colinérgicos , Serina-Treonina Quinases TOR , Animais , Masculino , Ratos , Aprendizagem da Esquiva/fisiologia , Medo/fisiologia , Hipocampo/metabolismo , Muscarina/farmacologia , Antagonistas Muscarínicos/farmacologia , Nicotina/farmacologia , Ratos Wistar , Receptores Colinérgicos/metabolismo , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Extinção Psicológica/fisiologia , Memória/fisiologia
10.
Front Microbiol ; 13: 1017278, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36267174

RESUMO

The RNA chaperone Hfq promotes the association of small RNAs (sRNAs) with cognate mRNAs, controlling the expression of bacterial phenotype. Actinobacillus pleuropneumoniae hfq mutants strains are attenuated for virulence in pigs, impaired in the ability to form biofilms, and more susceptible to stress, but knowledge of the extent of sRNA involvement is limited. Here, using A. pleuropneumoniae strain MIDG2331 (serovar 8), 14 sRNAs were identified by co-immunoprecipitation with Hfq and the expression of eight, identified as trans-acting sRNAs, were confirmed by Northern blotting. We focused on one of these sRNAs, named Rna01, containing a putative promoter for RpoE (stress regulon) recognition. Knockout mutants of rna01 and a double knockout mutant of rna01 and hfq, both had decreased biofilm formation and hemolytic activity, attenuation for virulence in Galleria mellonella, altered stress susceptibility, and an altered outer membrane protein profile. Rna01 affected extracellular vesicle production, size and toxicity in G. mellonella. qRT-PCR analysis of rna01 and putative cognate mRNA targets indicated that Rna01 is associated with the extracytoplasmic stress response. This work increases our understanding of the multilayered and complex nature of the influence of Hfq-dependent sRNAs on the physiology and virulence of A. pleuropneumoniae.

11.
Nature ; 608(7923): 558-562, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35948632

RESUMO

The productivity of rainforests growing on highly weathered tropical soils is expected to be limited by phosphorus availability1. Yet, controlled fertilization experiments have been unable to demonstrate a dominant role for phosphorus in controlling tropical forest net primary productivity. Recent syntheses have demonstrated that responses to nitrogen addition are as large as to phosphorus2, and adaptations to low phosphorus availability appear to enable net primary productivity to be maintained across major soil phosphorus gradients3. Thus, the extent to which phosphorus availability limits tropical forest productivity is highly uncertain. The majority of the Amazonia, however, is characterized by soils that are more depleted in phosphorus than those in which most tropical fertilization experiments have taken place2. Thus, we established a phosphorus, nitrogen and base cation addition experiment in an old growth Amazon rainforest, with a low soil phosphorus content that is representative of approximately 60% of the Amazon basin. Here we show that net primary productivity increased exclusively with phosphorus addition. After 2 years, strong responses were observed in fine root (+29%) and canopy productivity (+19%), but not stem growth. The direct evidence of phosphorus limitation of net primary productivity suggests that phosphorus availability may restrict Amazon forest responses to CO2 fertilization4, with major implications for future carbon sequestration and forest resilience to climate change.


Assuntos
Mudança Climática , Fósforo , Floresta Úmida , Solo , Árvores , Clima Tropical , Aclimatação , Dióxido de Carbono/metabolismo , Dióxido de Carbono/farmacologia , Sequestro de Carbono , Cátions/metabolismo , Cátions/farmacologia , Mudança Climática/estatística & dados numéricos , Modelos Biológicos , Nitrogênio/metabolismo , Nitrogênio/farmacologia , Fósforo/metabolismo , Fósforo/farmacologia , Solo/química , Árvores/efeitos dos fármacos , Árvores/metabolismo , Incerteza
12.
Pharmacol Biochem Behav ; 218: 173427, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35810923

RESUMO

In psychostimulant drug addiction, relapse is the most concerning outcome to be managed, considering there is no approved treatment for this neuropsychiatric condition. Here, we investigated the effects of the CBD treatment on the relapse behavior triggered by stress, after being submitted to the amphetamine (AMPH)-induced conditioned place preference (CPP) in rats. To elucidate the mechanisms of action underlying the CBD treatment, we evaluated the neuroadaptations on dopaminergic and endocannabinoid targets in the ventral striatum (VS) and ventral tegmental area (VTA) of the brain. Animals received d,l-AMPH (4 mg/kg, i.p.) or vehicle in the CPP paradigm for 8 days. Following the first CPP test, animals were treated with CBD (10 mg/kg, i.p.) or its vehicle for 5 days and subsequently submitted to forced swim stress protocol to induce AMPH-CPP relapse. Behavioral findings showed that CBD treatment prevented AMPH-reinstatement, also exerting anxiolytic activity. At the molecular level, in the VTA, CBD restored the CB1R levels decreased by AMPH-exposure, increased NAPE-PLD, and decreased FAAH levels. In the VS, the increase of D1R and D2R, as well as the decrease of DAT levels induced by AMPH were restored by CBD treatment. The current outcomes evidence a substantial preventive action of the CBD on the AMPH-reinstatement evoked by stress, also involving neuroadaptations in both dopaminergic and endocannabinoid systems in brain areas closely involved in the addiction. Although further studies are needed, these findings support the therapeutic potential of CBD in AMPH-relapse prevention.


Assuntos
Anfetamina , Canabidiol , Anfetamina/farmacologia , Animais , Canabidiol/farmacologia , Dopamina , Endocanabinoides/farmacologia , Ratos , Recidiva
13.
Environ Monit Assess ; 194(7): 482, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35668330

RESUMO

Bananas are a worldwide cultivated crop and one of the main agricultural activities in Brazil. The banana orchards cultivated in the region of São Paulo State are under native areas of the Atlantic Forest biome. The Atlantic Forest has suffered agricultural and urban pressure for many years. Banana crops require soil management and superficial vegetation removal in the first cycles. We conducted a study aiming to understand the impact of long-standing banana cultivation in the Atlantic forest region. Soil samples in banana plantations (EBP) and forest remnants (FR) were collected from trenches with 0- to 100-cm layers. The soil bulk density in EBP until 30-cm depth was 12.76% higher than that in FR. Quantifications of macropores and micropores in FR reached values higher than those in EBP. The results showed that carbon stocks decreased from the top to the deeper layers. Thirty years after the conversion, the FR treatment accumulated 28.23% more carbon than EBP. Considering our results, it was evident that changes in physical and chemical properties reflected the negative impacts of the banana plantations, cropped through conventional management, when converted from forest even in regard to a remnant one. These findings, showed for the first time, lead us to understand the soil management of banana plantations, following conventional agriculture systems, as a potential carbon stock reducer and a factor resulting in the loss of soil quality in the region. Additionally, our data can be used by environmentalists and government policymakers to promote environmental sustainability.


Assuntos
Musa , Solo , Agricultura , Brasil , Carbono/análise , Monitoramento Ambiental , Florestas , Solo/química
14.
Front Pharmacol ; 13: 759626, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35370690

RESUMO

Stress represents a major risk factor for psychiatric disorders, including post-traumatic stress disorder (PTSD). Recently, we dissected the destabilizing effects of acute stress on the excitatory glutamate system in the prefrontal cortex (PFC). Here, we assessed the effects of single subanesthetic administration of ketamine (10 mg/kg) on glutamate transmission and dendritic arborization in the PFC of footshock (FS)-stressed rats, along with changes in depressive, anxious, and fear extinction behaviors. We found that ketamine, while inducing a mild increase of glutamate release in the PFC of naïve rats, blocked the acute stress-induced enhancement of glutamate release when administered 24 or 72 h before or 6 h after FS. Accordingly, the treatment with ketamine 6 h after FS also reduced the stress-dependent increase of spontaneous excitatory postsynaptic current (sEPSC) amplitude in prelimbic (PL)-PFC. At the same time, ketamine injection 6 h after FS was found to rescue apical dendritic retraction of pyramidal neurons induced by acute stress in PL-PFC and facilitated contextual fear extinction. These results show rapid effects of ketamine in animals subjected to acute FS, in line with previous studies suggesting a therapeutic action of the drug in PTSD models. Our data are consistent with a mechanism of ketamine involving re-establishment of synaptic homeostasis, through restoration of glutamate release, and structural remodeling of dendrites.

15.
Neurochem Int ; 150: 105157, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34390773

RESUMO

Besides their clinical application, chronic misuse of opioids has often been associated to drug addiction due to their addictive properties, underlying neuroadaptations of AMPA glutamate-receptor-dependent synaptic plasticity. Topiramate (TPM), an AMPAR antagonist, has been used to treat psychostimulants addiction, despite its harmful effects on memory. This study aimed to evaluate the effects of a novel topiramate nanosystem on molecular changes related to morphine reinstatement. Rats were previously exposed to morphine in conditioned place preference (CPP) paradigm and treated with topiramate-chitosan nanoparticles (TPM-CS-NP) or non-encapsulated topiramate in solution (S-TPM) during CPP extinction; following memory performance evaluation, they were re-exposed to morphine reinstatement. While morphine-CPP extinction was comparable among all experimental groups, TPM-CS-NP treatment prevented morphine reinstatement, preserving memory performance, which was impaired by both morphine-conditioning and S-TPM treatment. In the NAc, morphine increased D1R, D2R, D3R, DAT, GluA1 and MOR immunoreactivity. It also increased D1R, DAT, GluA1 and MOR in the dorsal hippocampus. TPM-CS-NP treatment decreased D1R, D3R and GluA1 and increased DAT in the NAc, decreasing GluA1 and increasing D2 and DAT in the dorsal hippocampus. Taken together, we may infer that TPM-CS-NP treatment was able to prevent the morphine reinstatement without memory impairment. Therefore, TPM-CS-NP may be considered an innovative therapeutic tool due to its property to prevent opioid reinstatement because it acts modifying both dopaminergic and glutamatergic neurotransmission, which are commonly related to morphine addiction.


Assuntos
Quitosana/administração & dosagem , Dopamina/metabolismo , Ácido Glutâmico/metabolismo , Dependência de Morfina/metabolismo , Nanopartículas/administração & dosagem , Topiramato/administração & dosagem , Analgésicos Opioides/farmacologia , Animais , Condicionamento Psicológico/efeitos dos fármacos , Condicionamento Psicológico/fisiologia , Quimioterapia Combinada , Extinção Psicológica/efeitos dos fármacos , Extinção Psicológica/fisiologia , Masculino , Memória/efeitos dos fármacos , Memória/fisiologia , Morfina/farmacologia , Dependência de Morfina/prevenção & controle , Ratos , Ratos Wistar , Receptores de AMPA/metabolismo , Receptores Dopaminérgicos/metabolismo
16.
Eur Neuropsychopharmacol ; 50: 23-33, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33951588

RESUMO

Amphetamine (AMPH) is an addictive psychostimulant highly used worldwide and its consumption is related to neurotoxic effects. Currently, there is no pharmacotherapy approved for treating AMPH or other psychostimulant drug addiction. Different studies have shown promising properties of cannabidiol (CBD) for treating many neurological and psychiatric diseases, and recently, CBD is being considered a potential strategy for the treatment of drug addiction disorders. Thus, we investigated possible CBD beneficial effects on relapse symptoms following AMPH re-exposure considering drug relapse is the most difficult clinical factor to control during addiction treatment. Rats received d,l-AMPH (4 mg/kg, i.p.) or vehicle in the conditioned place preference (CPP) paradigm (8 days), when each experimental group was re-assigned to receive CBD at two different doses (5 or 10 mg/kg, i.p) or control, for 5 days. Subsequently, animals were re-exposed to AMPH-CPP (4 mg/kg, i.p.) for 3 additional days to assess relapse behavior. Besides locomotor and anxiety-like behaviors, dopaminergic molecular parameters were quantified in both prefrontal cortex and ventral striatum. Regarding molecular levels, CBD modulated at basal levels the dopaminergic targets (D1R, D2R, DAT, and TH) in the assessed brain areas, preventing AMPH relapse and decreasing anxiety-like behavior per se and in AMPH-CPP animals. The current findings give evidence about CBD-induced AMPH-relapse prevention, which may be linked to dopaminergic mesocorticolimbic system modulation. Although future and clinical studies are needed, our outcomes show that CBD may be a useful alternative to prevent AMPH relapse.


Assuntos
Transtornos Relacionados ao Uso de Anfetaminas , Canabidiol , Estimulantes do Sistema Nervoso Central , Anfetamina/farmacologia , Transtornos Relacionados ao Uso de Anfetaminas/terapia , Animais , Encéfalo/metabolismo , Canabidiol/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Dopamina , Ratos , Ratos Wistar , Receptores de Dopamina D2/metabolismo , Recidiva
17.
Neurochem Int ; 148: 105085, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34052297

RESUMO

Nutraceuticals have been the focus of numerous research in recent years and accumulating data support their use for promoting some health benefits. Several nutraceuticals have been widely studied as supplements due to their functional properties ameliorating symptoms associated with neurological disorders, such as oxidative stress and chronic inflammatory states. This seems to be the case of some fruits and seeds from the Amazon Biome consumed since the pre-Columbian period that could have potential beneficial impact on the human nervous system. The beneficial activities of these food sources are possibly related to a large number of bioactive molecules including polyphenols, carotenoids, unsaturated fatty acids, vitamins, and trace elements. In this context, this review compiled the research on six Amazonian fruits and seeds species and some of the major nutraceuticals found in their composition, presenting brief mechanisms related to their protagonist action in improving inflammatory responses and neuroinflammation.


Assuntos
Suplementos Nutricionais , Inflamação/tratamento farmacológico , Doenças Neuroinflamatórias/tratamento farmacológico , Plantas Medicinais/química , Rios , Animais , Produtos Biológicos , Brasil , Doença Crônica , Fenômenos Eletrofisiológicos , Humanos
18.
Chemosphere ; 278: 130417, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33839396

RESUMO

The exposure to environmental stressors, such as organophosphate (OP) pesticides, has been associated with the development of neurodegenerative diseases. Chlorpyrifos (CPF) is the worldwide most used OP pesticide and one of the most hazardous pesticides as it can cross the blood-brain barrier. Since studies evaluating the effects of CPF on brain immune cells are scarce, this research investigated the oxidative and inflammatory responses of CPF exposure in murine microglial cells. BV-2 cells were exposed to different concentrations of CPF pesticide (0.3-300 µM). CPF induced activation of microglial cells, confirmed by Iba-1 and CD11b marking, and promoted microglial proliferation and cell cycle arrest at S phase. Moreover, CPF exposure increased oxidative stress production (NO, MDA, and O2∙), and upregulated pro-inflammatory cytokines (IL-1ß and NLRP3) genes expression in BV-2 cells. Overall, data showed that CPF exposure, at the lowest concentrations, acted by promoting pro-oxidative and pro-inflammatory states in microglial cells. These results provide important information on the potential role of microglial activation in CPF-induced neuroinflammation and add to the expanding knowledge on the neurotoxicity of OP.


Assuntos
Clorpirifos , Inseticidas , Praguicidas , Animais , Clorpirifos/toxicidade , Camundongos , Microglia , Estresse Oxidativo , Praguicidas/toxicidade
19.
Front Microbiol ; 12: 773284, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069478

RESUMO

Mobile genetic elements (MGEs) and antimicrobial resistance (AMR) drive important ecological relationships in microbial communities and pathogen-host interaction. In this study, we investigated the resistome-associated mobilome in 345 publicly available Pasteurellaceae genomes, a large family of Gram-negative bacteria including major human and animal pathogens. We generated a comprehensive dataset of the mobilome integrated into genomes, including 10,820 insertion sequences, 2,939 prophages, and 43 integrative and conjugative elements. Also, we assessed plasmid sequences of Pasteurellaceae. Our findings greatly expand the diversity of MGEs for the family, including a description of novel elements. We discovered that MGEs are comparable and dispersed across species and that they also co-occur in genomes, contributing to the family's ecology via gene transfer. In addition, we investigated the impact of these elements in the dissemination and shaping of AMR genes. A total of 55 different AMR genes were mapped to 721 locations in the dataset. MGEs are linked with 77.6% of AMR genes discovered, indicating their important involvement in the acquisition and transmission of such genes. This study provides an uncharted view of the Pasteurellaceae by demonstrating the global distribution of resistance genes linked with MGEs.

20.
New Phytol ; 230(1): 116-128, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33341935

RESUMO

Soil nutrient availability can strongly affect root traits. In tropical forests, phosphorus (P) is often considered the main limiting nutrient for plants. However, support for the P paradigm is limited, and N and cations might also control tropical forests functioning. We used a large-scale experiment to determine how the factorial addition of nitrogen (N), P and cations affected root productivity and traits related to nutrient acquisition strategies (morphological traits, phosphatase activity, arbuscular mycorrhizal colonisation and nutrient contents) in a primary rainforest growing on low-fertility soils in Central Amazonia after 1 yr of fertilisation. Multiple root traits and productivity were affected. Phosphorus additions increased annual root productivity and root diameter, but decreased root phosphatase activity. Cation additions increased root productivity at certain times of year, also increasing root diameter and mycorrhizal colonisation. P and cation additions increased their element concentrations in root tissues. No responses were detected with N addition. Here we showed that rock-derived nutrients determined root functioning in low-fertility Amazonian soils, demonstrating not only the hypothesised importance of P, but also highlighting the role of cations. The changes in fine root traits and productivity indicated that even slow-growing tropical rainforests can respond rapidly to changes in resource availability.


Assuntos
Fósforo , Clima Tropical , Cátions , Florestas , Nitrogênio/análise , Raízes de Plantas/química , Solo , Árvores
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