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1.
Sci Rep ; 13(1): 12491, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528129

RESUMO

Animal venoms are rich sources of neuroactive compounds, including anti-inflammatory, antiepileptic, and antinociceptive molecules. Our study identified a protonectin peptide from the wasp Parachartergus fraternus' venom using mass spectrometry and cDNA library construction. Using this peptide as a template, we designed a new peptide, protonectin-F, which exhibited higher antinociceptive activity and less motor impairment compared to protonectin. In drug interaction experiments with naloxone and AM251, Protonectin-F's activity was decreased by opioid and cannabinoid antagonism, two critical antinociception pathways. Further experiments revealed that this effect is most likely not induced by direct action on receptors but by activation of the descending pain control pathway. We noted that protonectin-F induced less tolerance in mice after repeated administration than morphine. Protonectin-F was also able to decrease TNF-α production in vitro and modulate the inflammatory response, which can further contribute to its antinociceptive activity. These findings suggest that protonectin-F may be a potential molecule for developing drugs to treat pain disorders with fewer adverse effects. Our results reinforce the biotechnological importance of animal venom for developing new molecules of clinical interest.


Assuntos
Peptídeos , Venenos de Vespas , Camundongos , Animais , Venenos de Vespas/química , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Morfina/farmacologia , Analgésicos Opioides , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Dor/tratamento farmacológico , Analgésicos/farmacologia , Analgésicos/uso terapêutico
2.
Sci Rep ; 11(1): 15185, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34312413

RESUMO

Parkinson's disease (PD) is a progressive and chronic neurodegenerative disease of the central nervous system. Early treatment for PD is efficient; however, long-term systemic medication commonly leads to deleterious side-effects. Strategies that enable more selective drug delivery to the brain using smaller dosages, while crossing the complex brain-blood barrier (BBB), are highly desirable to ensure treatment efficacy and decrease/avoid unwanted outcomes. Our goal was to design and test the neurotherapeutic potential of a forefront nanoparticle-based technology composed of albumin/PLGA nanosystems loaded with dopamine (ALNP-DA) in 6-OHDA PD mice model. ALNP-DA effectively crossed the BBB, replenishing dopamine at the nigrostriatal pathway, resulting in significant motor symptom improvement when compared to Lesioned and L-DOPA groups. Notably, ALNP-DA (20 mg/animal dose) additionally up-regulated and restored motor coordination, balance, and sensorimotor performance to non-lesioned (Sham) animal level. Overall, ALNPs represent an innovative, non-invasive nano-therapeutical strategy for PD, considering its efficacy to circumvent the BBB and ultimately deliver the drug of interest to the brain.


Assuntos
Barreira Hematoencefálica/metabolismo , Dopamina/administração & dosagem , Dopamina/farmacocinética , Sistemas de Liberação de Medicamentos , Nanopartículas/administração & dosagem , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Humanos , Masculino , Camundongos , Nanopartículas/química , Nanopartículas/ultraestrutura , Nanotecnologia , Oxidopamina/toxicidade , Transtornos Parkinsonianos/induzido quimicamente , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química
3.
Drug Discov Today ; 24(11): 2202-2211, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31539640

RESUMO

Parkinson's disease (PD) is a neurodegenerative pathology of the central nervous system, mainly involving the selective and progressive loss of dopaminergic neurons from the substantia nigra, resulting in motor and non-motor symptoms. PD remains an incurable ailment; thus, treatments are limited to symptom alleviation. With long-term use, conventional treatments can become inefficient, often triggering possible side effects. Considering these drawbacks, drug discovery constantly turns to nature as a source of efficient therapeutics. Thus, this review explores animal venoms as a rich source of bioactive compounds with potent neuropharmacological profiles for the development of effective adjuvant treatments with fewer side effects, ultimately aiming for the neuroprotection of dopaminergic neurons and the symptomatic relief of PD.


Assuntos
Descoberta de Drogas/métodos , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Peçonhas/uso terapêutico , Animais , Linhagem Celular , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Humanos , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/farmacologia , Resultado do Tratamento , Peçonhas/administração & dosagem , Peçonhas/farmacologia
4.
Pharmacol Ther ; 188: 176-185, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29605457

RESUMO

The complex process of pain control commonly involves the use of systemic analgesics; however, in many cases, a more potent and effective polypharmacological approach is needed to promote clinically significant improvement. Additionally, considering side effects caused by current painkillers, drug discovery is once more turning to nature as a source of more efficient therapeutic alternatives. In this context, arthropod venoms contain a vast array of bioactive substances that have evolved to selectively bind to specific pharmacological targets involved in the pain signaling pathway, playing an important role as pain activators or modulators, the latter serving as promising analgesic agents. The current review explores how the pain pathway works and surveys neuroactive compounds obtained from arthropods' toxins, which function as pain modulators through their interaction with specific ion channels and membrane receptors, emerging as promising candidates for drug design and development.


Assuntos
Analgésicos/farmacologia , Venenos de Artrópodes/farmacologia , Animais , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/fisiologia , Humanos , Dor/fisiopatologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Canais de Sódio/efeitos dos fármacos , Canais de Sódio/fisiologia , Canais de Cátion TRPV/efeitos dos fármacos , Canais de Cátion TRPV/fisiologia
5.
J Photochem Photobiol B ; 166: 301-310, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28024281

RESUMO

Melanoma is the most aggressive and lethal form of skin cancer, responsible for >80% of deaths. Standard treatments for late-stage melanoma usually present poor results, leading to life-threatening side effects and low overall survival. Thus, it is necessary to rethink treatment strategies and design new tools for the treatment of this disease. On that ground, we hereby report the use of acai oil in nanoemulsion (NanoA) as a novel photosensitizer for photodynamic therapy (PDT) used to treat melanoma in in vitro and in vivo experimental models. NIH/3T3 normal cells and B16F10 melanoma cell lines were treated with PDT and presented 85% cell death for melanoma cells, while maintaining high viability in normal cells. Flow cytometry indicated that cell death occurred by late apoptosis/necrosis. Tumor bearing C57BL/6 mice treated five times with PDT using acai oil in nanoemulsion showed tumor volume reduction of 82% in comparison to control/tumor group. Necrotic tissue per tumor area reached its highest value in PDT-treated mice, supporting PDT efficacy. Overall, acai oil in nanoemulsion was an effective photosensitizer, representing a promising source of new photosensitizing molecules for PDT treatment of melanoma, a tumor with an inherent tendency to be refractory for this type of therapy.


Assuntos
Emulsões , Euterpe/química , Melanoma/tratamento farmacológico , Fotoquimioterapia , Óleos de Plantas/uso terapêutico , Animais , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Nanotecnologia
6.
PLoS One ; 10(11): e0140233, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26559061

RESUMO

Magnetic nanoparticles can be used for numerous in vitro and in vivo applications. However, since uptake by the reticuloendothelial system represents an obstacle for the achievement of nanoparticle diagnostic and therapeutic goals, the aim of the present study was to evaluate the uptake of dimercaptosuccinic acid coated magnetic nanoparticles by reticuloendothelial system phagocytic cells present in lymph nodes, spleen, and liver tissue and how the presence of these particles could have an impact on the morphology of these organs in capuchin monkeys (Sapajus spp.). Animals were intravenously injected with dimercaptosuccinic acid coated magnetic nanoparticles and euthanized 12 hours and 90 days post-injection. Organs were processed by transmission electron microscopy and histological techniques. Samples of spleen and lymph nodes showed no morphological changes. Nevertheless, liver samples collected 90 days post-administration showed slight morphological alteration in space of Disse. Moreover, morphometrical analysis of hepatic mitochondria was performed, suggesting a clear positive correlation between mitochondrial area and dimercaptosuccinic acid coated magnetic nanoparticles administration time. The present results are directly relevant to current safety considerations in clinical diagnostic and therapeutic uses of magnetic nanoparticles.


Assuntos
Magnetismo , Sistema Fagocitário Mononuclear/anatomia & histologia , Nanopartículas , Succímero/administração & dosagem , Animais , Cebus , Fígado/anatomia & histologia , Fígado/ultraestrutura , Linfonodos/anatomia & histologia , Linfonodos/ultraestrutura , Microscopia Eletrônica de Transmissão , Mitocôndrias Hepáticas , Sistema Fagocitário Mononuclear/ultraestrutura , Baço/anatomia & histologia , Baço/ultraestrutura
7.
Toxins (Basel) ; 7(8): 3179-209, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-26295258

RESUMO

Neurodegenerative diseases are relentlessly progressive, severely impacting affected patients, families and society as a whole. Increased life expectancy has made these diseases more common worldwide. Unfortunately, available drugs have insufficient therapeutic effects on many subtypes of these intractable diseases, and adverse effects hamper continued treatment. Wasp and bee venoms and their components are potential means of managing or reducing these effects and provide new alternatives for the control of neurodegenerative diseases. These venoms and their components are well-known and irrefutable sources of neuroprotectors or neuromodulators. In this respect, the present study reviews our current understanding of the mechanisms of action and future prospects regarding the use of new drugs derived from wasp and bee venom in the treatment of major neurodegenerative disorders, including Alzheimer's Disease, Parkinson's Disease, Epilepsy, Multiple Sclerosis and Amyotrophic Lateral Sclerosis.


Assuntos
Venenos de Abelha/uso terapêutico , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Venenos de Vespas/uso terapêutico , Animais , Venenos de Abelha/farmacologia , Humanos , Fármacos Neuroprotetores/farmacologia , Venenos de Vespas/farmacologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-26257776

RESUMO

The impact of neurological disorders in society is growing with alarming estimations for an incidence increase in the next decades. These disorders are generally chronic and can affect individuals early during productive life, imposing real limitations on the performance of their social roles. Patients can have their independence, autonomy, freedom, self-image, and self-confidence affected. In spite of their availability, drugs for the treatment of these disorders are commonly associated with side effects, which can vary in frequency and severity. Currently, no effective cure is known. Nowadays, the biopharmaceutical research community widely recognizes arthropod venoms as a rich source of bioactive compounds, providing a plethora of possibilities for the discovery of new neuroactive compounds, opening up novel and attractive opportunities in this field. Several identified molecules with a neuropharmacological profile can act in the central nervous system on different neuronal targets, rendering them useful tools for the study of neurological disorders. In this context, this review aims to describe the current main compounds extracted from arthropod venoms for the treatment of five major existing neurological disorders: stroke, Alzheimer's disease, epilepsy, Parkinson's disease, and pathological anxiety.

9.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484613

RESUMO

The impact of neurological disorders in society is growing with alarming estimations for an incidence increase in the next decades. These disorders are generally chronic and can affect individuals early during productive life, imposing real limitations on the performance of their social roles. Patients can have their independence, autonomy, freedom, self-image, and self-confidence affected. In spite of their availability, drugs for the treatment of these disorders are commonly associated with side effects, which can vary in frequency and severity. Currently, no effective cure is known. Nowadays, the biopharmaceutical research community widely recognizes arthropod venoms as a rich source of bioactive compounds, providing a plethora of possibilities for the discovery of new neuroactive compounds, opening up novel and attractive opportunities in this field. Several identified molecules with a neuropharmacological profile can act in the central nervous system on different neuronal targets, rendering them useful tools for the study of neurological disorders. In this context, this review aims to describe the current main compounds extracted from arthropod venoms for the treatment of five major existing neurological disorders: stroke, Alzheimers disease, epilepsy, Parkinsons disease, and pathological anxiety.


Assuntos
Animais , Animais Peçonhentos , Doenças do Sistema Nervoso/terapia , Venenos de Artrópodes/uso terapêutico
10.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954768

RESUMO

The impact of neurological disorders in society is growing with alarming estimations for an incidence increase in the next decades. These disorders are generally chronic and can affect individuals early during productive life, imposing real limitations on the performance of their social roles. Patients can have their independence, autonomy, freedom, self-image, and self-confidence affected. In spite of their availability, drugs for the treatment of these disorders are commonly associated with side effects, which can vary in frequency and severity. Currently, no effective cure is known. Nowadays, the biopharmaceutical research community widely recognizes arthropod venoms as a rich source of bioactive compounds, providing a plethora of possibilities for the discovery of new neuroactive compounds, opening up novel and attractive opportunities in this field. Several identified molecules with a neuropharmacological profile can act in the central nervous system on different neuronal targets, rendering them useful tools for the study of neurological disorders. In this context, this review aims to describe the current main compounds extracted from arthropod venoms for the treatment of five major existing neurological disorders: stroke, Alzheimer's disease, epilepsy, Parkinson's disease, and pathological anxiety.(AU)


Assuntos
Animais , Venenos de Artrópodes , Produtos Biológicos , Sistema Nervoso Central , Doenças do Sistema Nervoso
11.
IET Nanobiotechnol ; 8(4): 222-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25429501

RESUMO

Brosimum gaudichaudii Tréc. (Moraceae) is a common Brazilian Cerrado plant known by its pharmaceutical industry relevance. The authors investigated the latex protein components and potential biotechnological applications. Some protein fragments had their sequences elucidated, presenting similarities to jacalin and Kunitz-type trypsin inhibitors. Amino acid residue modifications were found, such as glutamine N-terminal residue cyclisation into pyroglutamic acid residue, and mass differences corresponding to hexoses and N-acetylhexosamine presence. The latex was used to produce a nanoscale structured film, which presented an increased attraction and reduced adhesion behaviours. The film presented high homogeneity, as observed by low nanoroughness values, probably because of its intrinsic components, such as the jacalin-like protein that has known agglutination properties. The immobilised Kunitz-type trypsin inhibitor presence in the latex film allow us to point out to applications related to this inhibition, as in active food packaging, since these peptidase inhibitors are able to inhibit pests and microorganism proliferation.


Assuntos
Látex/química , Moraceae/química , Nanoestruturas/química , Proteínas de Plantas/química , Sequência de Aminoácidos , Módulo de Elasticidade , Dados de Sequência Molecular , Peptídeos , Lectinas de Plantas , Alinhamento de Sequência
12.
Nano Rev ; 52014.
Artigo em Inglês | MEDLINE | ID: mdl-25317253

RESUMO

Malignant melanoma is the most aggressive form of skin cancer and has been traditionally considered difficult to treat. The worldwide incidence of melanoma has been increasing faster than any other type of cancer. Early detection, surgery, and adjuvant therapy enable improved outcomes; nonetheless, the prognosis of metastatic melanoma remains poor. Several therapies have been investigated for the treatment of melanoma; however, current treatment options for patients with metastatic disease are limited and non-curative in the majority of cases. Photodynamic therapy (PDT) has been proposed as a promising minimally invasive therapeutic procedure that employs three essential elements to induce cell death: a photosensitizer, light of a specific wavelength, and molecular oxygen. However, classical PDT has shown some drawbacks that limit its clinical application. In view of this, the use of nanotechnology has been considered since it provides many tools that can be applied to PDT to circumvent these limitations and bring new perspectives for the application of this therapy for different types of diseases. On that ground, this review focuses on the potential use of developing nanotechnologies able to bring significant benefits for anticancer PDT, aiming to reach higher efficacy and safety for patients with malignant melanoma.

13.
Nanomedicine (Lond) ; 6(9): 1529-44, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21675858

RESUMO

AIM: This work represents the first reported investigation on the effects of magnetic nanoparticles (MNPs) in nonhuman primates. Biodistribution, biocompatibility and nanotoxicity of maghemite nanoparticles stabilized with dimercaptosuccinic acid (DMSA) were accessed. MATERIALS & METHODS: A control animal was used and three other animals were intravenously injected with DMSA-MNPs and euthanized 12 h, 30 and 90 days following administration. Extracted organs were processed by histological techniques. An additional animal was used to collect blood samples to complementarily assess biocompatibility 12 h, 7, 15, 30, 60 and 90 days after DMSA-MNP injection. RESULTS: DMSA-MNPs were preferentially addressed to the lungs, liver and kidneys. Hematological and serum biochemical results corroborated histological findings, supporting DMSA-MNP biocompatibility while preserving both hepatic and renal normal activity. CONCLUSION: DMSA-MNPs were preferentially distributed to the lung, liver and kidneys. Furthermore, DMSA-MNPs were considered biocompatible, supporting their application as a promising nanomaterial platform for future biomedical use.


Assuntos
Magnetismo , Nanopartículas/química , Succímero/química , Succímero/farmacocinética , Animais , Haplorrinos , Microscopia Eletrônica de Transmissão , Nanopartículas/efeitos adversos , Nanopartículas/ultraestrutura , Succímero/efeitos adversos
14.
Rev Neurosci ; 19(2-3): 91-100, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18751517

RESUMO

The perceptual deficit hypothesis for schizophrenia is based on more general models of normal human visual perception, which have traditionally postulated that objects must compete for attention and processing space in the visual system. Recent evidence suggests that susceptibility of schizophrenics to the Müller-Lyer (ML) illusion may be a marker of vulnerability, detectable in prodromic patients, but disappearing with the progression of the illness. This illusion consists of overestimating the length of a straight line with converging arrowheads at the ends, while underestimating those with diverging arrowheads. Although the ML illusion has been shown to occur in touch as well as vision, it is not known whether abnormal contextual suppression extends to other sensory modalities in schizophrenics. Another challenge consists in verifying whether different visual parameters of the illusion which favor the magnocellular and parvocellular systems would have diverse ML illusion effects in schizophrenia. In this review we present data showing the degree of illusion in capuchin monkeys (Cebus spp.), a possible animal model for schizophrenia. To this end, a computer program was developed to conduct experiments in humans and non-human primates, allowing the display of illusory figures, manipulation of the stimuli's exposure time, interval between stimuli and number of trials. In the non-primate experiments, the visual illusion test based on achromatic ML illusion figures indicated the presence of the ML illusory effect in 10 capuchin monkeys. These results suggest that Cebus might be a good model for the experimental study of schizophrenia.


Assuntos
Ilusões Ópticas/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Esquizofrenia/diagnóstico , Esquizofrenia/fisiopatologia , Animais , Humanos , Esquizofrenia/patologia
15.
Behav Brain Res ; 182(1): 67-72, 2007 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-17586063

RESUMO

Visual illusions are formed by differences between the perception of one figure and its real physical characteristics. The Müller-Lyer illusion is the best known and most studied geometric illusion, consisting in the subject's judgment between two parallel lines that have the same size, one flanked with outward-pointing arrowheads, and the other with inward-pointing arrowheads. These arrowheads act as inductors that make the lines to be perceived as having different sizes, inward-pointing stimuli being estimated as longer. This study aimed to investigate the Müller-Lyer illusion in capuchin monkeys (Cebus apella), a New World primate not yet investigated for this illusion. For this purpose, stimuli were presented on a touch screen monitor. Ten adult subjects (five females and five males) were used. Before the tests, they were trained to discriminate between two physically different lines with and without arrowheads. The longer lines were always the positive (rewarded) stimuli. Regarding the Müller-Lyer Illusion test, all monkeys, unrespective of gender, demonstrated susceptibility to the illusion, by choosing preferentially the line with inward-pointing arrowheads. In order to determine the degree of the illusion, a point of subjective equality test (PSE) was performed. The PSE without arrowheads values were lower than the PSE with arrowheads. Thus, it was demonstrated that capuchin monkeys were susceptible to the Müller-Lyer illusion, once the perception of the lines' size was influenced by the presence of the arrowheads and by their orientation.


Assuntos
Cebus/fisiologia , Discriminação Psicológica/fisiologia , Ilusões/fisiologia , Julgamento/fisiologia , Animais , Comportamento Animal , Feminino , Masculino , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos
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