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1.
Molecules ; 28(22)2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38005400

RESUMO

Antibiotic resistance is now a first-order health problem, which makes the development of new families of antimicrobials imperative. These compounds should ideally be inexpensive, readily available, highly active, and non-toxic. Here, we present the results of our investigation regarding the antimicrobial activity of a series of natural and synthetic polyamines with different architectures (linear, tripodal, and macrocyclic) and their derivatives with the oxygen-containing aromatic functional groups 1,3-benzodioxol, ortho/para phenol, or 2,3-dihydrobenzofuran. The new compounds were prepared through an inexpensive process, and their activity was tested against selected strains of yeast, as well as Gram-positive and Gram-negative bacteria. In all cases, the conjugated derivatives showed antimicrobial activity higher than the unsubstituted polyamines. Several factors, such as the overall charge at physiological pH, lipophilicity, and the topology of the polyamine scaffold were relevant to their activity. The nature of the lipophilic moiety was also a determinant of human cell toxicity. The lead compounds were found to be bactericidal and fungistatic, and they were synergic with the commercial antifungals fluconazole, cycloheximide, and amphotericin B against the yeast strains tested.


Assuntos
Antibacterianos , Anti-Infecciosos , Humanos , Antibacterianos/farmacologia , Antibacterianos/química , Poliaminas/farmacologia , Poliaminas/química , Saccharomyces cerevisiae , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Testes de Sensibilidade Microbiana
2.
Int J Mol Sci ; 23(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35743175

RESUMO

Motor neuron diseases (MNDs) include sporadic and hereditary neurological disorders characterized by progressive degeneration of motor neurons (MNs). Sigma-1 receptor (Sig-1R) is a protein enriched in MNs, and mutations on its gene lead to various types of MND. Previous studies have suggested that Sig-1R is a target to prevent MN degeneration. In this study, two novel synthesized Sig-1R ligands, coded EST79232 and EST79376, from the same chemical series, with the same scaffold and similar physicochemical properties but opposite functionality on Sig-1R, were evaluated as neuroprotective compounds to prevent MN degeneration. We used an in vitro model of spinal cord organotypic cultures under chronic excitotoxicity and two in vivo models, the spinal nerve injury and the superoxide dismutase 1 (SOD1)G93A mice, to characterize the effects of these Sig-1R ligands on MN survival and modulation of glial reactivity. The antagonist EST79376 preserved MNs in vitro and after spinal nerve injury but was not able to improve MN death in SOD1G93A mice. In contrast, the agonist EST79232 significantly increased MN survival in the three models of MN degeneration evaluated and had a mild beneficial effect on motor function in SOD1G93A mice. In vivo, Sig-1R ligand EST79232 had a more potent effect on preventing MN degeneration than EST79376. These data further support the interest in Sig-1R as a therapeutic target for neurodegeneration.


Assuntos
Esclerose Lateral Amiotrófica , Esclerose Lateral Amiotrófica/metabolismo , Animais , Modelos Animais de Doenças , Ligantes , Camundongos , Camundongos Transgênicos , Neurônios Motores/metabolismo , Neuroproteção , Receptores sigma , Medula Espinal/metabolismo , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1/metabolismo , Receptor Sigma-1
3.
Int J Mol Sci ; 22(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203381

RESUMO

Loss of motor neurons (MNs) after spinal root injury is a drawback limiting the recovery after palliative surgery by nerve or muscle transfers. Research based on preventing MN death is a hallmark to improve the perspectives of recovery following severe nerve injuries. Sigma-1 receptor (Sig-1R) is a protein highly expressed in MNs, proposed as neuroprotective target for ameliorating MN degenerative conditions. Here, we used a model of L4-L5 rhizotomy in adult mice to induce MN degeneration and to evaluate the neuroprotective role of Sig-1R ligands (PRE-084, SA4503 and BD1063). Lumbar spinal cord was collected at 7, 14, 28 and 42 days post-injury (dpi) for immunohistochemistry, immunofluorescence and Western blot analyses. This proximal axotomy at the immediate postganglionic level resulted in significant death, up to 40% of spinal MNs at 42 days after injury and showed markedly increased glial reactivity. Sig-1R ligands PRE-084, SA4503 and BD1063 reduced MN loss by about 20%, associated to modulation of endoplasmic reticulum stress markers IRE1α and XBP1. These pathways are Sig-1R specific since they were not produced in Sig-1R knockout mice. These findings suggest that Sig-1R is a promising target for the treatment of MN cell death after neural injuries.


Assuntos
Neurônios Motores/efeitos dos fármacos , Neurônios Motores/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Receptores sigma/agonistas , Receptores sigma/metabolismo , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/metabolismo , Animais , Western Blotting , Feminino , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptor Sigma-1
4.
Front Pharmacol ; 12: 780588, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34955848

RESUMO

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disorder characterized by the death of motoneurons (MNs) with a poor prognosis. There is no available cure, thus, novel therapeutic targets are urgently needed. Sigma-1 receptor (Sig-1R) has been reported as a target to treat experimental models of degenerative diseases and, importantly, mutations in the Sig-1R gene cause several types of motoneuron disease (MND). In this study we compared the potential therapeutic effect of three Sig-1R ligands, the agonists PRE-084 and SA4503 and the antagonist BD1063, in the SOD1G93A mouse model of ALS. Pharmacological administration was from 8 to 16 weeks of age, and the neuromuscular function and disease progression were evaluated using nerve conduction and rotarod tests. At the end of follow up (16 weeks), samples were harvested for histological and molecular analyses. The results showed that PRE-084, as well as BD1063 treatment was able to preserve neuromuscular function of the hindlimbs and increased the number of surviving MNs in the treated female SOD1G93A mice. SA4503 tended to improve motor function and preserved neuromuscular junctions (NMJ), but did not improve MN survival. Western blot analyses revealed that the autophagic flux and the endoplasmic reticulum stress, two pathways implicated in the physiopathology of ALS, were not modified with Sig-1R treatments in SOD1G93A mice. In conclusion, Sig-1R ligands are promising tools for ALS treatment, although more research is needed to ascertain their mechanisms of action.

5.
Front Neurol ; 12: 693309, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34630277

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease affecting the neuromuscular system for which currently there is no effective therapy. Motoneuron (MN) degeneration involves several complex mechanisms, including surrounding glial cells and skeletal muscle contributions. Neuregulin 1 (NRG1) is a trophic factor present particularly in MNs and neuromuscular junctions. Our previous studies revealed that gene therapy overexpressing the isoform I (NRG1-I) in skeletal muscles as well as overexpressing the isoform III (NRG1-III) directly in the central nervous system are both effective in preserving MNs in the spinal cord of ALS mice, opening novel therapeutic approaches. In this study, we combined administration of both viral vectors overexpressing NRG1-I in skeletal muscles and NRG1-III in spinal cord of the SOD1G93A mice in order to obtain a synergistic effect. The results showed that the combinatorial gene therapy increased preservation of MNs and of innervated neuromuscular junctions and reduced glial reactivity in the spinal cord of the treated SOD1G93A mice. Moreover, NRG1 isoforms overexpression improved motor function of hindlimb muscles and delayed the onset of clinical disease. However, this combinatory gene therapy did not produce a synergic effect compared with single therapies, suggesting an overlap between NRG1-I and NRG1-III activated pathways and their beneficial effects.

6.
Peu ; 22(3): 114-119, jul. 2002. tab, graf
Artigo em Es | IBECS (Espanha) | ID: ibc-19045

RESUMO

El propósito de este artículo es conocer en qué situación se encuentra actualmente la Podologia en la sociedad catalana. De los resultados obtenidos en el estudio podemos destacar que todavía existe una cierta confusión entre el antiguo callista y el actual podólogo; además, un porcentaje elevado de personas desconoce muchas de las tareas que puede desarrollar el podólogo, como por ejemplo la cirugía del pie. Podemos constatar que, a pesar de esto, un porcentaje importante de personas afirma haber ido alguna vez al podólogo (aunque la frecuencia de visita es baja) y el principal motivo, sigue siendo la quiropodia, con mucha diferencia. Como conclusión final, creemos que es absolutamente necesario dar a conocer mejor nuestra profesión dentro de la sociedad, tanto a través de instituciones, como los propios podólogos en su quehacer diario. (AU)


Assuntos
Humanos , Podiatria/tendências , Espanha , Inquéritos e Questionários , Conhecimentos, Atitudes e Prática em Saúde
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