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1.
Pharmacol Biochem Behav ; 244: 173850, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39159761

RESUMO

RATIONALE: Although the mesocorticolimbic dopamine (DA) system is the main neurochemical substrate that regulates the addictive and reinforcing effects of ethanol (EtOH), other neurotransmitter systems, such as the acetylcholine (Ach) system, modulate DAergic function in the nucleus accumbens (nAcc). Previously, we reported that intra-nAcc administration of the nicotinic Ach receptor agonist cytisine increased oral EtOH self-administration. GABAB receptors in the nAcc are expressed in DAergic terminals, inhibit the regulation of DA release into the nAcc, and could modulate the effects of cytisine on oral EtOH self-administration. The present study assessed the effects of intra-nAcc administration of the GABAB receptor agonist baclofen (BCF) on the impacts of cytisine on oral EtOH self-administration. METHODS: Male Wistar rats were deprived of water for 23.30 h and then trained to press a lever to receive EtOH on an FR3 schedule until a stable response rate of 80 % was achieved. After this training, the rats received an intra-nAcc injection of the nAch receptor agonist cytisine, BCF, and cytisine or 2-hydroxysaclofen, BCF, and cytisine before they were given access to EtOH on an FR3 schedule. RESULTS: Intra-nAcc injections of cytisine increased oral EtOH self-administration; this effect was reduced by BCF, and 2-hydroxysaclofen blocked the effects of BCF. CONCLUSIONS: These findings suggest that the reinforcing effects of EtOH are modulated not only by the DA system but also by other neurotransmitter systems involved in regulating DA release from DAergic terminals.


Assuntos
Alcaloides , Azocinas , Baclofeno , Condicionamento Operante , Etanol , Agonistas dos Receptores de GABA-B , Agonistas Nicotínicos , Núcleo Accumbens , Quinolizinas , Ratos Wistar , Autoadministração , Animais , Masculino , Baclofeno/farmacologia , Baclofeno/administração & dosagem , Ratos , Alcaloides/farmacologia , Alcaloides/administração & dosagem , Azocinas/farmacologia , Azocinas/administração & dosagem , Quinolizinas/farmacologia , Quinolizinas/administração & dosagem , Agonistas dos Receptores de GABA-B/farmacologia , Agonistas dos Receptores de GABA-B/administração & dosagem , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Etanol/administração & dosagem , Etanol/farmacologia , Condicionamento Operante/efeitos dos fármacos , Agonistas Nicotínicos/farmacologia , Agonistas Nicotínicos/administração & dosagem , Administração Oral , Consumo de Bebidas Alcoólicas/tratamento farmacológico , Consumo de Bebidas Alcoólicas/psicologia , Alcaloides Quinolizidínicos
2.
Colloids Surf B Biointerfaces ; 242: 114098, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39067191

RESUMO

Despite the promising potential of Solanum plant glycoalkaloids in combating skin cancer, their clinical trials have been halted due to dose-dependent toxicity and poor water solubility. In this study, we present a rational approach to address these limitations and ensure colloidal stability of the nanoformulation over time by designing solid lipid-polymer hybrid nanoparticles (SLPH). Leveraging the biocompatible and cationic properties of polyaspartamides, we employed a new polyaspartamide derivative (P1) as a raw material for this class of nanostructures. Subsequently, we prepared SLPH through a one-step process involving hot-melt emulsification followed by ultrasonication. The physicochemical properties of the SLPH were thoroughly characterized using dynamic light scattering (DLS), ζ-potential analysis, nanoparticle tracking analysis (NTA), differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FT-IR), and transmission electron microscopy (TEM). The optimized formulation exhibited long-term stability over six months under low temperatures, maintaining a particle size around 200 nm, a polydispersity index (PdI) lower than 0.2, and a ζ-potential between +35-40 mV. Furthermore, we evaluated the cytotoxic effect of the SLPH against human cutaneous melanoma cells (SK-MEL-28) compared to human foreskin fibroblast cells (HFF-1). Encapsulation of glycoalkaloids into the nanoparticles (SLPH-GE) resulted in a two-fold greater selective cytotoxic profile for melanoma cells than glycoalkaloids-free (GE). The nanoparticles disrupted the stratum corneum barrier with a penetration depth of approximately 77 µm. These findings underscore the potential of the developed nanosystem as an effective glycoalkaloid carrier with suitable colloidal and biological properties for further studies in topical treatment strategies for cutaneous melanoma.


Assuntos
Lipídeos , Melanoma , Nanopartículas , Polímeros , Humanos , Nanopartículas/química , Lipídeos/química , Melanoma/tratamento farmacológico , Melanoma/patologia , Polímeros/química , Polímeros/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Tamanho da Partícula , Alcaloides/química , Alcaloides/farmacologia , Linhagem Celular Tumoral , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Administração Tópica , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Propriedades de Superfície
3.
Methods Mol Biol ; 2827: 435-443, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985287

RESUMO

Protoplasts are plant cells from which the pectocellulosic cell wall has been removed, thus keeping the plasma membrane intact. For plant secondary metabolites research, this system is a powerful tool to study the metabolites' dynamics inside the cells, such as the subcellular localization of proteins, characterization of gene function, transcription factors involved in metabolite pathways, protein transport machinery, and to perform single-cell omics studies. Due to its lack of a cell wall, better images of the interior of the cell can be obtained compared to the whole tissue. This allows the identification of specific cell types involved in the accumulation of specialized metabolites, such as alkaloids, given their autofluorescence properties. Here is a simplified protocol to obtain protoplasts from leaves and in vitro cell cultures from Argemone mexicana, which produces the pharmacologically important alkaloids berberine and sanguinarine.


Assuntos
Alcaloides , Argemone , Plantas Medicinais , Protoplastos , Protoplastos/metabolismo , Argemone/química , Argemone/metabolismo , Plantas Medicinais/metabolismo , Plantas Medicinais/química , Alcaloides/metabolismo , Folhas de Planta/metabolismo , Benzofenantridinas/metabolismo , Berberina/metabolismo , Isoquinolinas
4.
J Mol Model ; 30(7): 200, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850372

RESUMO

CONTEXT: Given the diverse pathophysiological mechanisms underlying Alzheimer's disease, it is improbable that a single targeted drug will prove successful as a therapeutic strategy. Therefore, exploring various hypotheses in drug design is imperative. The sequestration of Fe(II) and Zn(II) cations stands out as a crucial mechanism based on the mitigation of reactive oxygen species. Moreover, inhibiting acetylcholinesterase represents a pivotal strategy to enhance acetylcholine levels in the synaptic cleft. This research aims to investigate the analogs of Huperzine A, documented in scientific literature, considering of these two hypotheses. Consequently, the speciation chemistry of these structures with Fe(II) and Zn(II) was scrutinized using quantum chemistry calculations, molecular docking simulations, and theoretical predictions of pharmacokinetics properties. From the pharmacokinetic properties, only two analogs, HupA-A1 and HupA-A2, exhibited a theoretical permeability across the blood-brain barrier; on the other hand, from a thermodynamic standpoint, the enantiomers of HupA-A2 showed negligible chelation values. The enantiomers with the most favorable interaction parameters were S'R'HupA-A1 (ΔGBIND = -40.0 kcal mol-1, fitness score = 35.5) and R'R'HupA-A1 (ΔGBIND = -35.5 kcal mol-1, fitness score = 22.61), being compared with HupA (ΔGBIND = -41.75 kcal mol-1, fitness score = 39.95). From this study, some prime candidates for promising drug were S'R'HupA-A1 and R'R'HupA-A1, primarily owing to their favorable thermodynamic chelating capability and potential anticholinesterase mechanism. METHODS: Quantum chemistry calculations were carried out at B3LYP/6-31G(d) level, considering the IEF-PCM(UFF) implicit solvent model for water. The coordination compounds were assessed using the Gibbs free energy variation and hard and soft acid theory. Molecular docking calculations were conducted using the GOLD program, based on the crystal structure of the acetylcholinesterase protein (PDB code = 4EY5), where the ChemScore function was employed with the active site defined as the region within a 15-Å radius around the centroid coordinates (X = -9.557583, Y = -43.910473, Z = 31.466687). Pharmacokinetic properties were predicted using SwissADME, focusing on Lipinski's rule of five.


Assuntos
Acetilcolinesterase , Alcaloides , Doença de Alzheimer , Inibidores da Colinesterase , Simulação de Acoplamento Molecular , Sesquiterpenos , Doença de Alzheimer/tratamento farmacológico , Alcaloides/química , Sesquiterpenos/química , Humanos , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Acetilcolinesterase/metabolismo , Acetilcolinesterase/química , Barreira Hematoencefálica/metabolismo , Termodinâmica , Zinco/química , Modelos Moleculares , Ferro/química , Ferro/metabolismo
5.
Int J Mol Sci ; 25(11)2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38891950

RESUMO

Piperine, an active plant alkaloid from black pepper (Piper nigrum), has several pharmacological effects, namely antioxidant, anti-inflammatory and immunomodulatory effects, which involve inhibiting molecular events associated with various stages of cancer development. The aim of this study was to investigate the molecular mechanisms of action of piperine in relation to its potential anticancer effect on head and neck cancer cells. Parameters related to neoplastic potential and cytokine, protein and gene expression were investigated in head and neck cancer cell lines (HEp-2 and SCC-25) treated with piperine. The results of the tests indicated that piperine modified morphology and inhibited viability and the formation of cell colonies. Piperine promoted genotoxicity by triggering apoptosis and cell cycle arrest in the G2/M and S phases. A decrease in cell migration was also observed, and there was decreased expression of MMP2/9 genes. Piperine also reduced the expression of inflammatory molecules (PTGS2 and PTGER4), regulated the secretion of cytokines (IFN-γ and IL-8) and modulated the expression of ERK and p38. These results suggest that piperine exerts anticancer effects on tumor cells by regulating signaling pathways associated with head and neck cancer.


Assuntos
Alcaloides , Apoptose , Benzodioxóis , Neoplasias de Cabeça e Pescoço , Inflamação , Piperidinas , Alcamidas Poli-Insaturadas , Transdução de Sinais , Alcamidas Poli-Insaturadas/farmacologia , Benzodioxóis/farmacologia , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Alcaloides/farmacologia , Humanos , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/genética , Inflamação/metabolismo , Inflamação/tratamento farmacológico , Inflamação/genética , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Citocinas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos
6.
Chem Biodivers ; 21(8): e202400665, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38825721

RESUMO

Waltheria indica (Malvaceae) is a plant popularly used in folk medicine by traditional African and indigenous communities, and in various countries worldwide, to treat general inflammation. Several biological activities of this plant have been reported, including acetylcholinesterase inhibition and potential anti-human immunodeficiency virus (HIV), antinociceptive, analgesic, antifungal, anticancer, anti-inflammatory, leishmanicidal, trypanocidal, antioxidant, and antibacterial activities. The chemical profile of Waltheria indica was assessed by dereplication analysis using UPLC-MS/MS, and data acquisition was performed using chemoinformatics tools, such as Mass Spectrometry-Data Independent AnaLysis (MS-DIAL) and MS-FINDER softwares. The preprocessed data were sent to the GNPS to build a feature-based molecular network (FBMN). Thirty-three 4-quinolone alkaloids were annotated in the extracts and fractions of stems and roots, whereas 12 were annotated in the extracts and fractions of flowers and leaves. This represents an inaugural chemical investigation study employing UPLC-Q-TOF-MS/MS analysis, along with a molecular network approach, within this species and genus.


Assuntos
Alcaloides , Espectrometria de Massas em Tandem , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , 4-Quinolonas/química , 4-Quinolonas/farmacologia , 4-Quinolonas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Folhas de Planta/química , Raízes de Plantas/química , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/isolamento & purificação
7.
Toxicon ; 247: 107769, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-38795851

RESUMO

The presence of phytotoxins in plants constitutes a health risk for herbivores, particularly on ruminants who accidently consume them. Among the adverse effects produced by these are reproductive alterations, represented by abortion, infertility, and morphological alterations in neonates, which are frequently attributed to other causes. While in some cases the plants that contain such metabolites are known, other times they are not, leading to alterations that are difficult to treat considering that their toxicodynamics are unknown. The objective of this documentary research is to provide information on how metabolites such as phytoestrogens, L-mimosine, labdane diterpenoids - isocupressic acid, quinolizidine alkaloids and piperidine swainsonine, anabasine, coniine and associated alkaloids, among others, exert their action in the animal organism and the effects they produce.


Assuntos
Alcaloides , Reprodução , Ruminantes , Animais , Reprodução/efeitos dos fármacos , Plantas Tóxicas/toxicidade , Feminino , Intoxicação por Plantas/veterinária
8.
Chem Biodivers ; 21(8): e202400786, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38777789

RESUMO

This study carried out to investigate the anti-inflammatory and antinociceptive effect of tropane alkaloid (EB7) isolated from E. bezerrae. It evaluated the toxicity and possible involvement of ion channels in the antinociceptive effect of EB7, as well as its anti-inflammatory effect in adult zebrafish (Zfa). Docking studies with EB7 and COX-1 and 2 were also performed. The tested doses of EB7 (4, 20 and 40 mg/kg) did not show any toxic effect on Zfa during the 96h of analysis (LD50>40 mg/kg). They did not produce any alteration in the locomotor behavior of the animals. Furthermore, EB7 showed promising pharmacological effects as it prevented the nociceptive behavior induced by hypertonic saline, capsaicin, formalin and acid saline. EB7 had its analgesic effect blocked by amiloride involving the neuromodulation of ASICs in Zfa. In evaluating the anti-inflammatory activity, the edema induced by κ-carrageenan 3.5 % was reduced by the dose of 40 mg/kg of EB7 observed after the fourth hour of analysis, indicating an effect similar to that of ibuprofen. Molecular docking results indicated that EB7 exhibited better affinity energy when compared to ibuprofen control against the two evaluated targets binding at different sites in the cocrystallized COX-1 and 2 inhibitors.


Assuntos
Analgésicos , Simulação de Acoplamento Molecular , Peixe-Zebra , Animais , Analgésicos/farmacologia , Analgésicos/química , Analgésicos/isolamento & purificação , Tropanos/farmacologia , Tropanos/isolamento & purificação , Tropanos/química , Edema/tratamento farmacológico , Edema/induzido quimicamente , Carragenina/farmacologia , Ciclo-Oxigenase 2/metabolismo , Ciclo-Oxigenase 1/metabolismo , Bignoniaceae/química , Relação Dose-Resposta a Droga , Relação Estrutura-Atividade , Alcaloides/farmacologia , Alcaloides/isolamento & purificação , Alcaloides/química , Canais Iônicos Sensíveis a Ácido/metabolismo , Canais Iônicos Sensíveis a Ácido/química , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Estrutura Molecular
9.
J Ethnopharmacol ; 332: 118349, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-38762214

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Snakebite envenomation (SBE) is the world's most lethal neglected tropical disease. Bothrops jararaca is the species that causes the greatest number of SBEs in the South and Southeastern of Brazil. The main symptoms are local (inflammation, edema, hemorrhage, and myonecrosis) and systemic (hemorrhage, hemostatic alterations with consumptive coagulopathy, and death) effects. Species of the genus Siparuna, Siparunaceae, are used in folk and traditional medicine to treat SBE. However, limited information is available concerning Brazilian Siparuna species against SBE. AIM OF THE STUDY: To investigate the correlation between the compounds present in the extracts of five Siparuna species as potential agents against proteolytic activity, plasma coagulation, and phospholipase A2 (PLA2) activity caused by B. jararaca venom, using data obtained by UHPLC-MS/MS, biological activity, and multivariate statistics. MATERIALS AND METHODS: The ethanol extracts from leaves of S. ficoides, S. decipiens, S. glycycarpa, S. reginae, and S. cymosa were fractionated by liquid-liquid extraction using different solvents of increasing polarity (hexane, dichloromethane, ethyl acetate, and n-butanol), affording their respective extracts, totaling 25 samples that were assayed through in vitro plasma coagulation and proteolytic activity assays. Moreover, the extracts were analyzed by UHPLC-MS/MS, using electrospray ionization (ESI) and atmospheric-pressure chemical ionization (APCI) in negative and positive ionization modes. The data was processed in MZmine v. 2.53 and evaluated by multivariate statistical tests (PLS) using the software UnscramblerX v. 10.4. These data were also used to build molecular networks (GNPS), and some ions of interest could be annotated using the library of molecules on the GNPS platform. RESULTS: A total of 19 extracts inhibited B. jararaca-induced plasma coagulation, with emphasis on S. cymosa and S. reginae (800 s). The inhibition of the proteolytic activity was also promising, ranging from 16% (S. glycycarpa) to 99% (S. cymosa, S. decipiens, and S. reginae). In addition, most extracts from S. cymosa and S. reginae inhibited 70-90% of PLA2 activity. Based on data from positive mode APCI analyses, it was possible to obtain a statistic model with reliable predictive capacity which exhibited an average R2 of 0.95 and a Q2 of 0.88, indicating a robust fit. This process revealed five ions, identified as the alkaloids: coclaurine (1), stepholidine (2) O-methylisopiline (3), nornantenine (4) and laurolitsine (5). This is the first study to evidence the potential antivenom of alkaloids from Siparuna species. CONCLUSIONS: Altogether, our results give support to the popular use of Siparuna extracts in SBE accidents, suggesting their potential as an alternative or complementary strategy against envenoming by B. jararaca venom. The predicted ions in the chemometric analysis for the assayed activities can also be correlated with the blocking activity and encourage the continuation of this study for possible isolation and testing of individual compounds on the used models.


Assuntos
Alcaloides , Coagulação Sanguínea , Bothrops , Venenos de Crotalídeos , Extratos Vegetais , Animais , Coagulação Sanguínea/efeitos dos fármacos , Venenos de Crotalídeos/toxicidade , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Alcaloides/farmacologia , Alcaloides/isolamento & purificação , Alcaloides/química , Brasil , Proteólise/efeitos dos fármacos , Fosfolipases A2/metabolismo , Inibidores de Fosfolipase A2/farmacologia , Inibidores de Fosfolipase A2/isolamento & purificação , Folhas de Planta/química , Antivenenos/farmacologia , Antivenenos/isolamento & purificação , Inibidores de Proteases/farmacologia , Inibidores de Proteases/isolamento & purificação , Espectrometria de Massas em Tandem , Bothrops jararaca
10.
Food Res Int ; 186: 114333, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729693

RESUMO

Acrylamide is an amide formed in the Maillard reaction, with asparagine as the primary amino acid precursor. The intake of large amounts of acrylamide has induced genotoxic and carcinogenic effects in hormone-sensitive tissues of animals. The enzime asparaginase is one of the most effective methods for lowering the formation of acrylamide in foods such as potatoes. However, the reported sensory outcomes for coffee have been unsatisfactory so far. This study aimed to produce coffees with reduced levels of acrylamide by treating them with asparaginase while retaining their original sensory and bioactive profiles. Three raw samples of Coffea arabica, including two specialty coffees, and one of Coffea canephora were treated with 1000, 2000, and 3000 ASNU of the enzyme. Asparagine and bioactive compounds (chlorogenic acids-CGA, caffeine, and trigonelline) were quantified in raw and roasted beans by HPLC and LC-MS, while the determination of acrylamide and volatile organic compounds was performed in roasted beans by CG-MS. Soluble solids, titratable acidity, and pH were also determined. Professional cupping by Q-graders and consumer sensory tests were also conducted. Results were analyzed by ANOVA-Fisher, MFA, PCA and Cluster analyses, with significance levels set at p ≤ 0.05. Steam treatment alone decreased acrylamide content by 18.4%, on average, and 6.1% in medium roasted arabica and canefora coffees. Average reductions of 32.5-56.0% in acrylamide formation were observed in medium roasted arabica beans when 1000-3000 ASNU were applied. In the canefora sample, 59.4-60.7% reductions were observed. However, steam treatment primarily caused 17.1-26.7% reduction of total CGA and lactones in medium roasted arabica samples and 13.9-22.0% in canefora sample, while changes in trigonelline, caffeine, and other evaluated chemical parameters, including the volatile profiles were minimal. Increasing enzyme loads slightly elevated acidity. The only sensory changes observed by Q-graders and or consumers in treated samples were a modest increase in acidity when 3000 ASNU was used in the sample with lower acidity, loss of mild off-notes in control samples, and increased perception of sensory descriptors. The former was selected given the similarity in chemical outcomes among beans treated with 2000 and 3000 ASNU loads.


Assuntos
Acrilamida , Asparaginase , Asparagina , Coffea , Café , Paladar , Acrilamida/análise , Asparagina/análise , Coffea/química , Café/química , Humanos , Compostos Orgânicos Voláteis/análise , Culinária/métodos , Alcaloides/análise , Ácido Clorogênico/análise , Cafeína/análise , Masculino , Manipulação de Alimentos/métodos , Reação de Maillard , Temperatura Alta , Cromatografia Líquida de Alta Pressão , Sementes/química , Feminino
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