Search

Rauvolfia species are well known as producers of bioactive monoterpene indole alkaloids, which exhibit a broad spectrum of biological activities. A new vobasine-sarpagan-type bisindole alkaloid (1) along with six known monomeric indoles (2, 3/4, 5, and 6/7) were isolated from the ethanol extract of the roots of Rauvolfia ligustrina. The structure of the new compound was elucidated by interpretation of their spectroscopic data (1D and 2D NMR and HRESIMS) and comparison with published data for analog compounds. The cytotoxicity of the isolated compounds was screened in a zebrafish (Danio rerio) model. The possible GABAergic (diazepam as the positive control) and serotoninergic (fluoxetine as the positive control) mechanisms of action in adult zebrafish were also evaluated. No compounds were cytotoxic. Compound 2 and the epimers 3/4 and 6/7 showed a mechanism action by GABAA, while compound 1 showed a mechanism action by a serotonin receptor (anxiolytic activity). Molecular docking studies showed that compounds 2 and 5 have a greater affinity by the GABAA receptor when compared with diazepam, whereas 1 showed the best affinity for the 5HT2AR channel when compared to risperidone.

Turnera subulata Sm. belongs to the family Turneraceae and is found in Brazil. The present study evaluated the antinociceptive, anti-inflammatory, and hypoglycemic potential of T. subulata flower e...

Combretaceae are reported in the literature for presenting neuroprotective and anxiolytic effects in animal models. Combretum lanceolatum Pohl. has few scientific reports on its pharmacological eff...

Drugs used to manage type 2 diabetes mellitus cause adverse effects. Therefore, the search for new drugs as an alternative for the treatment of diabetes increases. The effect of triterpene 3β-6β-16β-trihydroxylup-20(29)-ene isolated from the leaves of C. leprosum (CLF-1) on sucrose-induced hyperglycemia in adult zebrafish (Danio rerio) was evaluated. Initially, adult zebrafish (n = 6/group) underwent hyperglycemia induction by sucrose at 83.25 mM/L for 7 days by immersion. The hyperglycemic groups were treated with CLF-1 (4, 20, and 40 mg/kg), metformin (200 mg/kg), and acarbose (300 mg/kg) for 4 days. The in silico interaction of CLF-1, metformin, and acarbose with the enzyme maltase-glucoamylase (CtMGAM) was investigated. CLF-1 reduced sucrose-induced hyperglycemia after 4 days of treatment, in addition to having better affinity energy with CtMGAM than metformin and acarbose. Thus, CLF-1 may be a new pharmacological alternative as a hypoglycemic agent for the treatment of diabetes.

Background: Plant lectins have shown promising biological activities in the central nervous system (CNS). Objective: This study evaluated the effect of DAL, a lectin isolated from the seeds of the Dioclea altissima species, having binding affinity to D-glucose or D-mannose residues, on mice behavior. Methods: Mice (n=6/group) were treated (i.p.) with DAL (0.25, 0.5 or 1 mg/kg) or vehicle and subjected to several tests (open field/OFT, marble-burying/MBT, hole-board/HBT, elevated plus maze/PMT, tail suspension/ TST, forced swimming/FST or rotarod/RRT). Pizotifen, cyproheptadine, flumazenil, L-NAME, 7-NI, Larginine or yohimbine were administered 15 min before DAL (0.5 mg/kg) and the animals were evaluated on PMT. It was also verified whether the DAL effect depended on its structural integrity and ability to interact with carbohydrates. Results: The results showed there were no neurobehavioral changes in the mice at the RRT, FST and locomotion in the OFT. DAL (0.25, 0.5 or 1 mg/kg) increased the behavior of grooming and rearing in the OFT, head dips in the HBT, pedalling in the TST and decreased the number of marbles hidden in the MBT. In the PMT, DAL (0.25, 0.5 and 1 mg/kg) and Diazepam increased the frequency of entries in the open arms and the time of permanence in the open arms without affecting the locomotor activity. The effect of DAL was dependent on carbohydrate interaction and protein structure integrity and it prevented by pizotifen, cyproheptadine, flumazenil, L-NAME and 7-NI, but not by L-arginine or yohimbine. Conclusion: DAL was found to have an anxiolytic-like effect mediated by the 5-HT and GABAergic receptors and NO pathway.

The action of anxiolytic compounds that act on selective serotonin receptors (SSRIs) have been scarcely evaluated. Serotonergic drugs have been shown to be effective in treating anxiety without presenting adverse effects as benzodiazepines. However, the anxiolytic effects take days to occur. This study aimed to evaluate the anxiolytic effect of the synthetic chalcone, 4’-[(2E) -3- (3-nitrophenyl) -1- (phenyl) prop-2-en-1-one] acetamide (PAAMNBA), and its possible mechanism of action in adult zebrafish (Danio rerio). PAAMNBA was synthesized with a yield of 51.3% and its chemical structure was determined by 1H and 13C NMR. Initially, PAAPMNBA was intraperitoneally administered to zebrafish (n = 6/group) at doses of 4, 12, or 40 mg/kg, and the animals were subsequently subjected to acute and open field toxicity tests. PAAMNBA was administered to the other groups (n = 6/group) for analyzing its effect in the light and dark test. The involvement of the serotonergic (5HT) system was also evaluated using 5-HTR 1, 5-HTR 2A/2C, and 5-HTR 3A/3B receptor antagonists, namely, pizotifeo, granizetron, and ciproeptadina, respectively. Molecular coupling was performed using the 5-HT1 receptor. PAAMNBA was found to be non-toxic, reduced the locomotor activity, and had an anxiolytic effect in adult zebrafish. The effect was reduced by pretreatment with pizotifene and was not reversed by treatment with granizetron and cyproeptadine. A previous in vivo molecular coupling study indicated that chalcones interact with the 5-HT1 receptor. The results suggested that the chalcone, PAAPMNBA, has anxiolytic activity, that is mediated by the serotonergic system via the 5-HT1 receptor. The interaction of PAAPMNBA with the 5-HT1 receptor was confirmed by molecular docking studies.

Este trabalho busca a avaliacao da seguranca nao clinica do triterpeno AAA frente aos ensaios com zebrafish ( Danio rerio ) adulto. O triterpeno AAA foi isolado da raiz de Croton zehntneri . Solucoes desta substância foram preparadas com salina 0,9 %, nas concentracoes de (4,0 mg/kg ou 12 mg/kg ou 40 mg/kg; 20 μL i.p) e submetidas ao teste de toxicidade aguda frente ao modelo zebrafish. As mesmas doses foram investigadas quanto ao possivel efeito ansiolitico, atraves do teste de campo aberto. As tres dosagens de AAA testadas nao foram toxicas nos zebrafish e nao reduziram a atividade locomotora do animal, tendo assim uma possivel acao nociceptiva pois a amostra nao alterou a atividade locomotora dos animais.

Comumente a industria farmaceutica utiliza metabolitos secundarios isolados de plantas como material de partida natural de novos farmacos. As plantas podem ser utilizadas como fontes terapeuticas alternativas, pois apresentam em sua composicao variedades de moleculas biologicamente ativas, como os triterpenos. Esses constituintes sao metabolitos secundarios pertencente a classe dos terpenos e sao caracterizados quimicamente pela presenca de seis unidades de isopreno, com um total de 30 atomos de carbono. Esta revisao foi realizada com base nos artigos publicados sobre triterpenos e suas bioatividades: anti-inflamatoria, antiadipogenica, antinociceptiva, antimicrobiana e anticâncer, em relacao ao periodo dos ultimos dez anos. Nesta revisao foi verificado que, as atividades relatadas comprovam que os triterpenos constituem grande potencial terapeutico.

Diabetes mellitus is a chronic metabolic disorder that has been increasing drastically around the worldwide. It is important to emphasize that although many drugs are commercially available to treat diabetes, many of them have shown a number of adverse effects. Therefore, search for new antidiabetic agents is of great interest, and natural products, especially those obtained from plants sources, may be an alternative to available drugs. This study reports the in vivo and in silico evaluation of the hypoglycemic activity of fisetinidol. The conformational analysis confirmed that the fisetinidol compound possesses two valleys in the potential energy curve, showing a stable conformer on the global minimum of the PES defined by the dihedral angle θ (C6-C7-O-H) at 179.9°, whose energy is equal to zero. In addition, fisetinidol has shown promise in glycemic control and oxidative stress caused by hyperglycemia induced by high sucrose concentration, causing hypoglycemic and hepatoprotective effects in adult zebrafish. ADMET studies showed that fisetinidol has high passive permeability, low clearance and low toxic risk by ingestion, and computational studies demonstrated that fisetinidol complexes in the same region as metformin and α-acarbose, which constitutes a strong indication that fisetinidol has the same inhibitory mechanisms of α-acarbose and metformin. Communicated by Ramaswamy H. Sarma.

Anxiety is a mental disorder that affects 25% of patients with epilepsy, and treatments for anxiety and seizures involve the use of benzodiazepines, a class of drugs that have many adverse effects such as decreased motor coordination, drowsiness, and sedation. Thus, new types of drugs with minimal side effects are of immediate requirement. Chalcones comprise a class of compounds with important therapeutic potential and have recently been investigated for their potential as anxiolytic and anticonvulsant agents. Therefore, this study aimed to evaluate the anxiolytic and anticonvulsant effects of the synthetic chalcone (E)-3-(furan-2-yl)-1-(2hydroxy-3,4,6-trimethoxyphenyl)prop-2-en-1-one (FURCHAL) using adult zebrafish as an animal model. Anxiolytic potential was assessed using the light/dark test and the anticonvulsant effect in 3-stage pentylenetetrazol (PTZ)-induced seizure tests. The mechanisms of the anxiolytic effect were analyzed using γ-aminobutyric acid (GABA) and the serotoninergic system. The anxiolytic effect of FURCHAL was verified by a reduction in fish locomotion, similar to diazepam (DZP), which may involve the GABA

Neem fruit (Azadirachta indica A. Juss.) are popularly used to treat infections, diarrhea, fever, bronchitis, skin diseases, infected burns and hypertension. Although the antinociceptive and anti-inflammatory potential of A. indica has already been investigated in experimental models of pain and inflammation in mice, the current research is the first to report the evaluation of the capacity of A. indica fruit ethanolic extract (EtFrNeem) in acute pain attenuation using the adult zebrafish (Danio rerio) as an alternative model to the use in rodents. EtFrNeem was submitted to antioxidant action, preliminary chemical prospecting, FT-IR and determination of phenol and flavonoid content tests. Subsequently, EtFrNeem was tested for acute nociception and abdominal inflammation, locomotor activity, and acute toxicity in adult zebrafish. Possible neuromodulation mechanisms were also evaluated. EtFrNeem showed low antioxidant activity, but was shown to be rich in flavonoids. EtFrNeem showed no anti-inflammatory action, did not alter the locomotor system, and it was not toxic. However, EtFrNeem significantly reduced the nociceptive behavior induced by formalin, glutamate and acidic saline, when compared to the control group. These effects of EtFrNeem were significantly similar to those of morphine, used as a positive control. The antinociceptive effect of EtFrNeem was inhibited by naloxone, ketamine and amiloride. EtFrNeem has the pharmacological potential for acute pain treatment and this effect is modulated by the opioid system, NMDA receptors and ASICs channels. These results lead us to studies of isolation and characterization of EtFrNeem bioactive principles, using adult zebrafish as an experimental model.

Benzodiazepines are highly effective in combating anxiety; however, they have considerable adverse effects, so it is important to discover new safe anxiolytic agents. This study was designed to investigate the anxiolytic and anticonvulsant effect of natural product 2-hydroxy-3,4,6-trimethoxyacetophenone (HTMCX) and its possible mechanisms of action in adult zebrafish. The open field and light / dark tests (n = 6 animals/group) were used to assess anxiety and pentylenetetrazole (PTZ) as a seizure inducer. The 96-hour acute toxicity of HTMCX was also investigated. HTMCX (1, 3, and 10 mg / kg; v.o.) was not toxic and affected locomotor activity. The highest doses (3 and 10 mg / kg; v.o.) produced signs of anxiolytic action in the light / dark test, and this effect was abolished by the pizotifen (antagonist 5HTR1 and 5HTR2A / 2C), having the potential to form a complex in the same region of the site indicating that the anxiolytic effect via the serotonergic mechanism. However, the anxiolytic effect of HTMCX has not been abolished by flumazenil (antagonist GABARA), cyproheptadine (antagonist 5HTR2A), and granisetron (antagonist 5HTR3A / 3B). Therefore, HTMCX demonstrated an anxiolytic effect, suggesting that the 5HTR1 and 5HTR / 2C receptors may be involved in the pharmacological performance of this acetophenone in the central nervous system.

Benzodiazepines (GABA receptor agonists) and serotonin reuptake inhibitors (SSRIs) are the drugs of choice for the treatment of anxiety. However, they have considerable adverse effects, so it is important to discover new anxiolytic agents. In this work, the 4′-[(1E,2E)-1-(2-(2′,4′-dinitrophenyl)hydrazone-3-(4-methoxyphenyl)allyl)aniline (HYDRAZDN) was synthesized and characterized by 1H and 13C NMR, 2D-NMR, ATR-FTIR, FT-Raman, and UV-Vis spectroscopy, and their structural and spectroscopic proprieties were evaluated by quantum chemistry theoretical calculations. Properties such as drug-likeness and pharmacokinetics were also estimated. The anxiolytic-like effect of the compound was also evaluated using adult zebrafish (Danio rerio). The results showed that the HYDRAZDN compound caused a reduction in zebrafish locomotor activity and induced maximum permanence of zebrafish in the clear zone at a dose of 40 mg/kg, an effect similar to the effect of positive control diazepam (DZP: 40 mg/kg). To identify the mechanism of action of the anxiolytic effect of this compound, we used flumazenil, an antagonist at the benzodiazepine binding site at GABAA receptors. The treatment with the highest dose of HYDRAZDN (40 mg/kg) and DZP (40 mg/kg) caused anxiolytic behavior in the animals that spent most of their time in the dark region of the aquarium. This effect was reduced by flumazenil, indicating that anxiolytic activity of the synthesized hydrazone occurs through the GABAergic system.

Croton zehntneri is a plant known as canelinha de cunha, prevalent in the northeast region of Brazil. Many constituents of the vegetable have already been studied, and their pharmacological properties have been proven, but this is the first study to analyze the antinociceptive effect in adult zebrafish (ZFa) of the triterpene acetyl aleuritolic acid (AAA) isolated from the stem bark. The animals (ZFa; n = 6/group) were treated intraperitoneally (ip; 20 μL) with AAA (0.1 or 0.3 or 1.0 mg/mL) or vehicle (0.9% saline; 20 μL), and submitted to the locomotor activity test, as well as 96 h acute toxicity. Other groups (n = 6/each) received the same treatments and underwent acute nociception tests (formalin, cinnamaldehyde, glutamate, acid saline, capsaicin, and hypertonic saline). Possible neuromodulation mechanisms were evaluated. AAA (0.1 or 0.3 or 1.0 mg/mL) reduced the nociceptive behavior induced by acid saline and capsaicin, as well as inhibited corneal nociception induced by hypertonic saline, both without altering the animals’ locomotor system and without toxicity. These analgesic effects of AAA were significantly (p > 0.05) similar to those of morphine, used as a positive control. The antinociceptive effect of AAA was inhibited by methylene blue, ketamine, camphor, ruthenium red, amiloride, and mefenamic acid. The antinociceptive effect of AAA on the cornea of animals was inhibited by capsazepine. Therefore, AAA showed pharmacological potential for the treatment of acute pain, and this effect is modulated by cGMP, NMDA receptors, transient receptor potential channels (TRPs), ASICs and has pharmacological potential for the treatment of corneal pain modulated by the TRPV1 channel.

Drugs used to treat pain are associated with adverse effects, increasing the search for new drugs as an alternative treatment for pain. Therefore, we evaluated the antinociceptive behavior and possible neuromodulation mechanisms of triterpene 3β, 6β, 16β-trihydroxylup-20(29)-ene (CLF-1) isolated from Combretum leprosum leaves in zebrafish. Zebrafish (n = 6/group) were pretreated with CLF-1 (0.1 or 0.3 or 1.0 mg/mL; i.p.) and underwent nociception behavior tests. The antinociceptive effect of CFL-1 was tested for modulation by opioid (naloxone), nitrergic (L-NAME), nitric oxide and guanylate cyclase synthesis inhibitor (methylene blue), NMDA (Ketamine), TRPV1 (ruthenium red), TRPA1 (camphor), or ASIC (amiloride) antagonists. The corneal antinociceptive effect of CFL-1 was tested for modulation by TRPV1 (capsazepine). The effect of CFL-1 on zebrafish locomotor behavior was evaluated with the open field test. The acute toxicity study was conducted. CLF-1 reduced nociceptive behavior and corneal in zebrafish without mortalities and without altering the animals’ locomotion. Thus, CFL-1 presenting pharmacological potential for the treatment of acute pain and corneal pain, and this effect is modulated by the opioids, nitrergic system, NMDA receptors and TRP and ASIC channels.

Óleos essenciais são substâncias odoríficas, encontrados por várias partes das plantas. A atividade locomotora avalia drogas que causam comprometimento locomotor ou não. O objetivo desse trabalho foi obter o óleo essencial do cravo da Índia e realizar a avaliação da segurança não clínica utilizando zebrafish. O OE foi obtido por meio de hidrodestilação. Para o teste de campo aberto, os zebrafish receberam doses de OE (4, 20 e 40 mg/kg); DMSO 3% e DZP 40mg/kg. Após 30 min, os animais foram adicionados em placas de Petri, e analisada a atividade locomotora através da contagem do número de CL (5 min). Para avaliação da toxicidade, os animais receberam os mesmos tratamentos e após 96h h de análise, os valores obtidos com o número de ZFa mortos foram submetidos à análise estatística para estimar DL para matar 50%. O OE apresentou composição elevada teor de eugenol e baixos teores de acetato de eugenila e ß-cariofileno. Além disso, alterou o sistema locomotor do zebrafish e é considerado seguro, pois não se mostrou tóxico até 96h de análise.

Background: Plant lectins have shown promising neuropharmacological activities in animal models. Objective: This study evaluated the effect of Dioclea altissima seed lectin (DAL) on adult zebrafish behavior. Method: Zebrafish (n=6/group) were treated (i.p.; 20 μL) with DAL (0.025; 0.05 or 0.1 mg/mL), vehicle or diazepam (DZP) and submitted to several tests (open field, light/dark preference or novel tank). Flumazenil, pizotifen or granisetron were administered 15 min before DAL (0.05 mg/mL), and the animals were evaluated on light/dark preference test. It was also verified whether the DAL effect depended on its structural integrity and ability to interact with carbohydrates. Results: DAL decreased the locomotor activity of adult zebrafish (0.025; 0.05 or 0.1 mg/mL), increased the time spent in the upper region of the aquarium (0.025 mg/mL), and decreased the latency time of adult zebrafish to enter the upper region on the novel tank test. DAL (0.05 mg/mL) also increased their permanence in the light zone of the light/dark preference test. The effect of DAL was dependent on carbohydrate interaction and protein structure integrity and was prevented by pizotifen, granizetron and flumazenil. Conclusion: DAL was found to have an anxiolytic-like effect mediated by the 5-HT and GABAergic receptors.

As chalconas sao cetonas aromaticas que ocorrem naturalmente, consistindo de um sistema de carbonila α,β-insaturado que une dois aneis aromaticos. E uma classe de flavonoides de cadeia aberta, abundantemente encontradas em plantas das familias Leguminosae, Compositae e Moraceae, estao presentes em frutas, vegetais, graos, raizes, flores, chas, vinhos, produtos regularmente utilizados para consumo humano, assim como podem ser modificadas por reacoes de hidroxilacao, condensacao ou metilacao. Pesquisas que investigam as propriedades das chalconas tem mostrado um grande espectro de atividade biologica, o que vem reforcando desde o isolamento, sintese, identificacao e investigacao dos efeitos biologicos. Esta revisao foi realizada com base nos artigos cientificos publicados sobre chalconas, enfatizando as seguintes atividades farmacologicas: antioxidante, antinociceptiva, antinflamatoria, ansiolitica e anticonvulsivante em relacao ao periodo dos ultimos dez anos. Diante disto, as atividades relatadas, mostraram resultados significativos de trabalhos que investigaram diferentes potenciais farmacologico das chalconas e seus derivados a fim de se obter informacoes preliminares no desenvolvimento possiveis farmacos.

In this work, an ibuprofen derivative 2-(4-isobutylphenyl) -N'-phenylpropanohydrazide (ACPHZN) was synthesized and characterized by NMR, ATR-FTIR, FT-Raman, and UV-Vis spectroscopy, while their structural and spectroscopic properties were investigated using DFT calculations. In vivo study using animal model in an adult Zebrafish (Danio rerio), and molecular docking was performed. In addition, molecular descriptors of the properties of absorption, distribution, metabolism and excretion, and toxicity (ADMET) were obtained. The data calculated for ibuprofen derivative are in accordance with the experimental values. From the assays in adult zebrafish, it was found that the ibuprofen derivative was non-toxic and exhibited analgesic properties through the TRPA1, TRPV1 and TRPM8 channels. Molecular docking revealed six interactions of ACPHZN with residues of the capsaicin binding site, and a more favorable affinity energy (-9.0 kcal / mol). ADMET studies suggest that ACPHZN has a pharmacological principle as an oral drug based on a longer half-life in the human body.

Benzodiazepines are commonly used to treat disorders of the central nervous system, including anxiety. However, due to their adverse effects, there is a continuing interest in discovering new safe and effective drugs. Marine natural products have emerged as a prolific source of bioactive nitrogenated compounds. Aiming to discover new biologically active natural compounds, the marine sponge Aplysina fulva, a nitrogen-bearing heterocyst producer, was investigated. The main isolated compounds (4, 6, and 9) were evaluated on adult zebrafish (Danio rerio). A group of fishes (n = 6) was preliminarily subjected to acute toxicity, and open field tests using 0.1, 0.5, and 1.0 mg/mL (v. o.) of those compounds was performed. The anxiolytic effect was further investigated in the light/dark assay based on the locomotor response at zebrafish. Interactions through the GABAergic system were investigated using flumazenil, a silent modulator of GABA receptors. To improve the results, a study of molecular docking using the GABAA receptor also was performed. Based on the results, the bromotyrosine derivative compounds 4, 6, and 9 exhibited anxiolytic-like effects mediated by the GABAergic system.

In the treatment of anxiety and seizures, drugs of the benzodiazepine (BZD) class are used, which act on the Central Nervous System (CNS) through the neurotransmitter gamma-aminobutyric acid (GABA). Flavonoids modulate GABAA receptors. The aim of this study was to evaluate the anxiolytic and anticonvulsant effects of synthetic chalcones and their mechanisms of action via the GABAergic system, using adult zebrafish (ZFa). The animals were treated with chalcones (4.0 or 20 or 40 mg/kg; 20 µL; i.p) and submitted to the open field and 96 h toxicity test. Chalcones that cause locomotor alteration were evaluated in the light and dark anxiolytic test. The same doses of chalcones were evaluated in the anticonvulsant test. The lowest effective dose was chosen to assess the possible involvement in the GABAA receptor by blocking the flumazenil (fmz) antagonist. No chalcone was toxic and altered ZFa’s locomotion. All chalcones had anxiolytic and anticonvulsant effects, mainly chalcones 1, where all doses showed effects in both tests. These effects were blocked by Fmz (antagonist GABAA), where it shows evidence of the performance of these activities of the GABA system. Therefore, this study demonstrated in relation to structure–activity, that the position of the substituents is important in the intensity of activities and that the absence of toxicity and the action of these compounds in the CNS, shows the pharmacological potential of these molecules, and, therefore, the insights are designed for the development of new drugs.

Zebrafish is a model animal that is used for neurobehavioral studies. It is an excellent model organism for pharmacological studies and/or safety research at an early stage of drug development. In this work, the chalcone (2E, 4E)-1-(2‑hydroxy-3,4,6-trimethoxyphenyl)-5-phenylpenta-2,4‑dien‑1-one, was synthesized by the Claisen-Schmidt condensation from two natural products: 2‑hydroxy-3,4,6-trimethoxyacetophenone and cinnamaldehyde. The molecular structure of this compound was confirmed by spectroscopic methods such as NMR, Infrared, UV–vis, and quantum chemical calculations. In addition, the anxiolytic-like effect of the cinnamaldehyde chalcone in adult zebrafish (Danio rerio) was evaluated. The results showed that chalcone caused an approximately 80% reduction in zebrafish locomotor activity and induced maximum permanence of zebrafish in the clear zone (61.16%) at a dose of 0.5 mg kgl−1. The data suggest that the cinnamaldehyde chalcone has anxiolytic activity.

The molecule N-{4’-[(E)-3-(Fluorophenyl)-1-(phenyl)-prop-2-en-1-one]} chalcone (PAAPFBA) was recently synthesized due to the growing interest in the chemistry of the chalcone. The quantum chemical calculations were carried out to make a complete theoretical characterization (structural, spectroscopy, nonlinear optical, and electronic properties) employing three Density Functional Theory (DFT) methods like B3LYP, mPW1PW91, and M06–2X at 6–311++G(d,p) basis set. After all these characterizations, the antioxidant activity was studied using the reaction with the compound DPPH in methanol solution and the mechanism was investigated theoretically. All the three DFT methods used can describe with great accuracy the PAAPFBA chalcone: the results of infrared spectroscopy and the 1H and 13C isotropic shielding demonstrate to be in excellent agreement with the experimental data. The nonlinear optical (NLO) properties show that the title chalcone can be used with great potential in NLO devices and this result is in good agreement with the Natural Bond Orbital (NBO) analysis, which shows how the electronic density is delocalized within the molecule. Finally, the experimental data of the antioxidant activity showed a moderate rate of reaction with the DPPH molecule (50.92%) and this fact was proved by the theoretical mechanisms with the Hydrogen Atom Transfer (HAT) mechanism more favorable.

Benzodiazepines are the standard drugs for the treatment of anxiety, but their undesirable side effects make it necessary to develop new anxiolytic drugs. The objective of this study was to evaluate the possible anxiolytic-simile effect of synthetic chalcone N-{(4′-[(E)-3-(4-fluorophenyl)-1-(phenyl) prop-2-en-1-one]} acetamide (PAAPFBA) on adult zebrafish (Danio rerio). PAAPFBA was synthesized with an 88.21% yield and its chemical structure was determined by 1H and 13C NMR. Initially, animals (n = 6/group) were treated (4 or 12 or 40 mg/kg, intraperitoneal) with PAAPFBA and were submitted to acute toxicity and open field tests. Then, other groups (n = 6/each) received PAAPFBA for the analysis of its effect on the Light & Dark Test. The participation of the GABAergic system was also assessed using the GABAA antagonist flumazenil. Molecular docking was performed using the GABAA receptor. The effect of PAAPFBA on anxiety induced by alcohol withdrawal was analyzed. PAAPFBA was non-toxic, reduced the locomotor activity, and showed an anxiolytic-like effect in both models. This effect was reduced by pre-treatment with the flumazenil. In agreement with in vivo studies, molecular docking indicated an interaction between chalcone and the GABAA receptor. The results suggest that PAAPFBA is an anxiolytic agent mediated via the GABAergic system.