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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...

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.

Aims To test for the possible antinociceptive effect of nifedipine in rodent models of acute and chronic neuropathic orofacial pain and the possible involvement of TRP- and NMDA-related processes in this effect. Methods Acute nociceptive behavior was induced by administering formalin, cinnamaldehyde, glutamate, capsaicin, or acidified saline to the upper lip or hypertonic saline to the cornea of Swiss mice. Acute nociceptive behavior was also induced by formalin injected into the TMJ or mustard oil injected into the masseter muscle of Wistar rats. The chronic pain model involved infraorbital nerve transection (IONX) in Wistar rats to induce mechanical hypersensitivity, which was assessed with von Frey hair stimulation of the upper lip. The effects of pretreatment with nifedipine or vehicle (control) were tested on the nociceptive behaviors. Docking experiments were also performed. Statistical analysis included one-way ANOVA followed by Tukey post hoc test and two-way ANOVA followed by Bonferroni post hoc test (statistical significance P Results Nifedipine produced significant antinociceptive effects in all of the acute nociceptive behaviors except that induced by capsaicin. The antinociceptive effects were attenuated by NMDA, TRPA1, or TRPM3 receptor antagonists. The IONX animals developed facial mechanical hypersensitivity, which was significantly reduced by nifedipine. The docking experiments suggested that nifedipine may interact with TRPM3 and NMDA receptors. Conclusion The present study has provided novel findings in a variety of acute and chronic orofacial pain models showing that nifedipine, a selective inhibitor of L-type Ca2+ channels, can suppress orofacial nociceptive behavior through NMDA, TRPA1, and TRPM3 receptor systems.

Croton heliotropiifolius Kunth (Euphorbiaceae), whose occurrence has already been registered in the most varied Brazilian biomes, is commonly found in the Chapada do Araripe, Ceará. The species is traditionally used to treat fungal, parasitic, and degenerative diseases. This study investigated the chemical composition and pharmacological potential (antioxidant, antifungal, antiparasitic, and cytotoxic) of an aqueous extract obtained from the roots of C. heliotropiifolius. Following a qualitative phytochemical screening, the chemical constituents were identified by ultra-efficiency liquid chromatography coupled witha quadrupole/time-of-flight system (UPLC-QTOF). The antioxidant potential was verified by thin-layer chromatography (TLC). The direct and combined antifungal activity of the extract against opportunistic Candida strains was investigated using the microdilution method. The minimal fungicidal concentration (MFC) was determined by subculture, while the modulation of the morphological transition (fungal virulence) was evaluated by light microscopy. The in vitro antiparasitic activity was analyzed using epimastigotes of Trypanosoma cruzi and promastigotes of Leishmania braziliensis and Leishmania infantum, while cytotoxicity was determined in cultures of mouse fibroblasts. The phytochemical analysis identified the presence of acids, terpenes, flavonoids, lignans, and alkaloids. Among these constituents, the presence of polar and non-polar phenolic compounds with known antioxidant action was highlighted. While the extract showed clinically ineffective antifungal effects, it could enhance the effectiveness of fluconazole, in addition to inhibiting the morphological transition associated with increased virulence in Candida strains. Although the extract showed low cytotoxicity against fibroblasts, it also had weak antiparasitic effects. In conclusion, Croton heliotropiifolius is a source of natural products with antifungal and antioxidant potential.

The acute effects of hyperglycemia in cognitive function and mood are not well elucidated. The aim of this study was to evaluate whether acute hyperglycemia alters the exploratory behavior of adult zebrafish. Fish were maintained aquariums containing 55 mM D-glucose solution for 14 days. Blood glucose levels and behavioral analysis were assessed before and after the D-glucose challenge. Immersion of adult zebrafish in a 55 mM D-glucose solution (14 days) increased blood glucose levels until the 14th day. There was no difference in weight gain between the two groups. Hyperglycemia did not induce anxiogenic or anxioly-tic behavior, nor did it alter the locomotor activity of the animals. We conclude that acute hyperglycemia does not alter the exploratory behavior of the adult zebrafish.

Background Vanillosmopsis arborea Baker has recognized economic value owing to the high content of (-)-α-bisabolol (BISA) in the essential oil of its stem (EOVA). The antinociceptive effect of EVOA has already been demonstrated, and β-cyclodextrin (βCD) is known to improve the analgesic effect of various substances. Purpose Thus, we aimed to evaluate the orofacial antinociceptive effect of a complex containing EOVA-βCD in rodents. Methods EOVA was obtained by simple hydrodistillation, and the essential oil was complexed with βCD. The animals (n = 6/group) were treated orally with EOVA-βCD (10 or 50 mg/kg), or vehicle (control), and subjected to cutaneous orofacial nociception (formalin, capsaicin, acidic saline or glutamate), corneal (hypertonic saline) or temporomandibular (formalin) tests. The expression of FOS protein was analyzed in the spinal cord. Molecular docking was performed using the 5-HT3 and M2 receptors and BISA. Results The oral administration of EOVA-βCD reduced nociceptive behaviour. Moreover, EOVA-βCD decreased FOS expression. The molecular docking study indicates that BISA interacts with 5-HT3 and M2 receptors, indicating the potential mechanism of action of the tested compound. Conclusions Our results indicate that EOVA-βCD possesses orofacial antinociceptive effect, indicating that this complex can be used in analgesic drug development.

This study aimed to evaluate the antinociceptive effect of oleanolic acid using adult zebrafish models of orofacial pain. Acute nociception was induced by formalin, capsaicin, cinnamaldehyde, menthol, acidified saline or glutamate (cutaneous modes) and hypertonic saline (corneal model). In another set of experiments, animals were pre-treated with naloxone, L-NAME, methylene blue, ketamine, camphor, HC-030031, mefenamic acid, ruthenium red or amiloride to investigate the mechanism of antinociception. The involvement of central afferent C-fibers was also investigated. A molecular docking was performed using the TRPV1 channel. Motor activity was evaluated with the open field test. Pre-treatment with oleanolic acid significantly reduced nociceptive behavior associated with acute pain. Antinociception was effectively inhibited by ruthenium red and capsaicin-induced desensitization. Presence of trpv1 was confirmed by RT-PCR in cerebral tissue of zebrafish. In line with in vivo experiments, docking studies indicated that oleanolic acid may interact with TRPV1. Results confirm the potential pharmacological relevance of oleanolic acid as an inhibitor of orofacial nociception mediated by TRPV1.

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.

The aim of this study was to evaluate the antinociceptive effect of Kaempferol-3-O-rutinoside (KR), isolated from the plant Ouratea fieldingiana, on the orofacial nociception and possible mechanisms of action. Adult zebrafish (Danio rerio) were tested as a behavioral model to study formalin, glutamate, capsaicin, cinnamaldehyde and acidic saline-induced orofacial nociception, using as parameter the number of times the fish crossed the lines between the quadrants of a glass Petri dish during a specific time. Morphine was used as positive control. The effect of KR was tested for modulation by opioid (naloxone), nitrergic (L-NAME), TRPV1 (ruthenium red), TRPA1 (camphor) or ASIC (amiloride) antagonists. The effect of KR on zebrafish locomotor behavior was evaluated with the open field test. KR did not alter the fish's locomotor system and significantly reduced the orofacial nociceptive behavior induced by all noxious agents compared to the control group. The antinociceptive effect of KR was similar to morphine. All antagonists inhibited the antinociceptive effect of KR. KR has pharmacological potential for the treatment of acute orofacial pain and this effect is modulated by the opioid and nitrergic systems as well as TRPV1, TRPA1 and ASIC channels. These results can lead to the development of a new natural product for the treatment of orofacial pain and confirm the popular use of O. fieldingiana leaf for pain relief.

Croton blanchetianus is known as ‘marmeleiro preto’, a very widespread shrub in Northeast Brazil. Terpenoids, steroids and phenolic compounds are among the reported secondary metabolites of the Croton genus that are a potential source of bioactive compounds. This study evaluated the anxiolytic potential of clerodine-type diterpene, sonderianin (CBWS) isolated from the stem bark of C. blanchetianus and its mechanism of action in adult zebrafish (Danio rerio) (ZFa). The anticonvulsant and anti-acetylcholinesterase effects have also been explored. ZFa (n = 6/group) were treated intraperitoneally (ip; 20 µL) with CBWS (4, 12 and 40 mg/kg) and vehicle (3% DMSO; 20 µL) and subjected to locomotor activity tests, as well as toxicity acute 96 h. CBWS was also administered for analysis in the light/dark test. The involvement of the serotonergic system (5-HT) was investigated using 5-HTR1, 5-HTR2A/2C and 5-HTR3A/3B receptor antagonists. Anxiolytic doses were tested for pentylenetetrazol-induced seizure in ZFa. The inhibitory activity of the enzyme acetylcholinesterase (AChE) was measured. CBWS was not considered toxic and reduced locomotor activity. The results of the present study identified for the first time the interaction of the diterpene sonderianina in the CNS. This study provides evidence that CBWS has an anxiolytic effect mediated by serotonergic (5-HT) involvement and anti-acetylcholinesterase action. The 5-HTR1 and 5-HTR2A/2C receptors may be implicated in the low anticonvulsant effect in CBWS. Communicated by Ramaswamy H. Sarma

The aim of this study was to evaluate the anxiolytic-like effect of chrysophanol (CHRY), isolated from hexane extract of Senna cana stem and its possible mechanism of action. CHRY was obtained through chromatographic treatments and its identity was confirmed by uni and bidimensional RMN1H and RMN13C. Adult zebrafish (n = 6/group) were treated (with CHRY (4.0 or 12.0 or 40.0 mg/Kg; 20 µL; intraperitoneally) and submitted to acute toxicity and open field tests. Subsequently, other groups (n = 6/each) received CHRY for the analysis of its effect on the Light & Dark Test. The participation of the GABAergic system was also assessed using the diazepam (GABAA receptor agonist) and flumazenil (GABAA receptor antagonist). CHRY was considered non-toxic, it did not reduce the locomotor activity, and showed an anxiolytic-like effect. This effect was reduced by pre-treatment with flumazenil. The results suggest that CHRY is an anxiolytic-like agent mediated via the GABAergic system.

Antimicrobial resistance and the consequent inefficiency of antibiotics are the main problems faced by medicine. In view of this, numerous researches have been aimed at looking for new agents with antibacterial activity, among them natural products. Thus, this study aims to evaluate the antioxidant activity of aqueous and hydroalcoholic extracts of the leaves and roots of Spondias tuberosa by Thin Layer Chromatography (TLC), as well as to verify the antibacterial action of the extracts alone and in combination with commercial antibiotics to evaluate its potential in action of change of antibiotics. The extracts showed polar and nonpolar phenolic substances with antioxidant action. The Minimum Inhibitory Concentration (MIC) of the hydroalcoholic extracts of the leaves and roots was 1,024 μg/mL compared to the Staphylococcus aureus 25923 strain, whereas with the other strains, the products showed an MIC ≥ 2,048 µg/mL. The effect of combining extracts with amikacin, ampicillin and norfloxacin against the multidrug-resistant bacteria Escherichia coli 06, Staphylococcus aureus 10 and Pseudomonas aeruginosa 24 resulted in synergistic effects with aminoglycoside alone, achieving up to 75 % reduction in the MIC of the antibiotic. In view of the results obtained, it can be concluded that the extracts of S. tuberosa presented polar and nonpolar phenolic substances, in the antibacterial activity it can positively modify the effect of the aminoglycoside antibiotic against multi-resistant bacteria, but future studies are necessary to discover the mechanism of action of such an effect. La resistencia a los antimicrobianos y la consiguiente ineficacia de los antibióticos son los principales problemas a los que se enfrenta la medicina. Ante esto, numerosas investigaciones se han dirigido a buscar nuevos agentes con actividad antibacteriana, entre ellos productos naturales. Así, este estudio tiene como objetivo evaluar la actividad antioxidante de extractos acuosos e hidroalcohólicos de las hojas y raíces de Spondias tuberosa mediante Cromatografía de Capa Fina (CCF), así como verificar la acción antibacteriana de los extractos solos y en combinación con antibióticos comerciales para evaluar su potencial en la acción del cambio de antibióticos. Los extractos mostraron sustancias fenólicas polares y apolares con acción antioxidante. La Concentración Mínima Inhibitoria (CMI) de los extractos hidroalcohólicos de hojas y raíces fue de 1.024 μg / mL en comparación con la cepa Staphylococcus aureus 25923, mientras que con las otras cepas, los productos mostraron una CMI ≥ 2.048 µg / mL. El efecto de combinar extractos con amikacina, ampicilina y norfloxacina contra la bacteria multirresistente Escherichia coli 06, Staphylococcus aureus 10 y Pseudomonas aeruginosa 24 resultó en efectos sinérgicos con el aminoglucósido solo, logrando reducción de hasta un 75 % en la CMI del antibiótico. A la vista de los resultados obtenido, se puede concluir que los extractos de S. tuberosa presentó sustancias fenólicas polares y apolares, en el actividad antibacteriana puede modificar positivamente el efecto del antibiótico aminoglucósido contra bacterias multirresistentes, pero el futuro son necesarios estudios para descubrir el mecanismo de acción de tal efecto. A resistência antimicrobiana e a consequente ineficiência de antibióticos são os principais problemas enfrentados pela medicina. Diante disto, inúmeras pesquisas têm sido destinadas a procurar novos agentes com atividade antibacteriana, dentre eles os produtos naturais. Dessa forma, esse estudo tem como objetivo avaliar a atividade antioxidante dos extratos aquosos e hidroalcoólicos das folhas e raízes de S. tuberosa Arruda (umbu) por Cromatografia em Camada Delgada (CCD), bem como verificar a ação antibacteriana dos extratos isoladamente e em combinação com antibióticos comerciais para avaliar seu potencial na ação de modificação de antibióticos. Os extratos apresentaram substâncias fenólicas polares e apolares com ação antioxidante. A Concentração Inibitória Mínima (CIM) dos extratos hidroalcoólicos das folhas e raízes foi 1024 μg/mL frente a cepa Staphylococcus aureus 25923, já com as demais cepas os produtos demonstraram uma CIM ≥ 2.048 µg/mL. O efeito da combinação dos extratos com amicacina, ampicilina e norfloxacina frente às bactérias multirresistentes Escherichia coli 06, Staphylococcus aureus 10 e Pseudomonas aeruginosa 24 resultou em efeitos sinérgicos apenas com o aminoglicosídeo, alcançando até 75 % de redução da CIM do antibiótico. Diante dos resultados obtidos, pode-se concluir que os extratos de S. tuberosa apresentaram substâncias fenólicas polares e apolares, na atividade antibacteriana pode modificar positivamente o efeito do antibiótico aminoglicosídeo contra bactérias multirresistentes, mas estudos futuros é preciso para descobrir o mecanismo de ação de tal efeito.

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.

Cashew apple extract (CAE) is a product with intense yellow color obtained from residual fibers of juice processing. Although CAE is known to be rich in carotenoids and anacardic acids, the biological activities of this potential natural food colorant remain unexplored. The present study is the first to investigate the toxicity, antiproliferative and antimicrobial activities of the lyophilized CAE (L-CAE) and its encapsulated products, using maltodextrin (M-CAE) or cashew gum (CG-CAE) as carriers. In addition to their high carotenoid content, the phenolic contents in all materials was determined using UPLC-QTOF-MS(E). The acute toxicity was performed using adult zebrafish (Danio rerio); antiproliferative activity was assessed using seven different human tumor cell lines [U-251 (glioblastoma), MCF-7 (breast, adenocarcinoma), NCI-ADR/RES (multidrug-resistant ovarian adenocarcinoma), NCI-H-460 (lung, large cell carcinoma), PC-3 (prostate, adenocarcinoma), OVCAR-3 (ovarian adenocarcinoma), and HT-29 (colon, adenocarcinoma)] and an immortalized human keratinocyte (HaCaT) while the antimicrobioal activity was evaluated on Staphylococcus aureus ATCC 25923, Listeria monocytogenes ATCC 19115, Escherichia coli ATCC 25922 and Salmonella Typhimurium ATCC 51812 microorganisms. Both lyophilized and encapsulated CAE samples did not exert acute toxicity against zebrafish neither antiproliferative effect against human tumor and non-tumor cell lines. Further, L-CAE showed potential antimicrobial activity against Listeria monocytogenes, which was confirmed using electron microscopy. The current findings demonstrated that CAE is a potential source of bioactive compounds to use as an additive in the food industry. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13197-020-04594-0) contains supplementary material, which is available to authorized users.

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.

To ensure the antimicrobial activity of the aqueous extract of chambá, it is essential to protect its bioactive compounds. The objective was to preserve its characteristics, aiming to provide the food industry with a natural antimicrobial. Three microcapsule formulations made with maltodextrin and cyclodextrin were developed, both including the aqueous extract of chambá leaves dried through lyophilization. The aqueous extract was initially submitted to in vivo toxicity analysis using zebrafish and the microcapsules were characterized through studies of morphology, hygroscopicity, water solubility, particle size, zeta potential, color determination, microencapsulation efficiency and antimicrobial activity. The aqueous extract of chambá was not considered to be toxic. The microcapsules had irregular shapes, with sizes varying from 0.58 to 1.15 µm. Solubility values ranged from 74.69 to 76.8% and hygroscopicity varied from 2.07 to 4.34%. Additionally, it obtained efficient encapsulation of the phenolic compounds, showing antimicrobial activity against Staphylococcus aureus, Listeria monocytogenes, Salmonella Enteritidis and Escherichia coli, with its use being an alternative as a natural antimicrobial agent. RESUMO Para assegurar a atividade antimicrobiana do extrato aquoso de chambá é essencial proteger seus compostos bioativos. Objetivou-se preservar as suas características, visando proporcionar a indústria de alimentos um antimicrobiano natural. Três formulações de microcápsulas foram elaboradas com maltodextrina e ciclodextrina, ambas juntamente com o extrato aquoso de folhas de chambá e secas por liofilização. O extrato aquoso foi inicialmente submetido à análise de toxicidade in vivo utilizando zebrafish e as microcápsulas foram caracterizadas por estudo da morfologia, higroscopicidade, solubilidade em água, tamanho de partículas, potencial zeta, determinação da cor, eficiência da microencapsulação e atividade antimicrobiana. O extrato aquoso de chambá não foi considerado tóxico. As microcápsulas apresentaram formas irregulares, tamanhos variando de 0,58 a 1,15 µm. Valores de solubilidade de 74,69 a 76,8%. A higrocospicidade variou de 2,07 a 4,34 %. Além disso, obteve eficiente encapsulação dos compostos fenólicos, apresentando atividade antimicrobiana diante Staphylococcus aureus, Listeria monocytogenes, Salmonella Enteritidis e Escherichia coli, sendo uma alternativa sua utilização como antimicrobiano natural.

The aim of this study was to identify and evaluate the chemical compositions and effects of the S. tuberosa leaf and root hydroalcoholic extracts (HELST and HERST) against different strains of Candida. Chemical analysis was performed by Ultra-Performance Liquid Chromatography Coupled to Quadrupole/Time of Flight System (UPLC-MS-ESI-QTOF). The Inhibitory Concentration of 50% of the growth (IC50) as well as the intrinsic and combined action of the extracts with the antifungal fluconazole (FCZ) were determined by the microdilution method while the minimum fungicidal concentrations (MFCs) and the effect on fungal morphological transitions were analyzed by subculture and in humid chambers, respectively. From the preliminary phytochemical analysis, the phenols and flavonoids were the most abundant. The intrinsic IC50 values for HELST ranged from 5716.3 to 7805.8 &micro, g/mL and from 6175.4 to 51070.9 &micro, g/mL for the HERST, whereas the combination of the extracts with fluconazole presented IC50 values from 2.65 to 278.41 &micro, g/mL. The MFC of the extracts, individually, for all the tested strains was &ge, 16384 &micro, g/mL. When fluconazole was combined with each extract, the MFC against CA URM 5974 was reduced (HELST: 2048 and HERST: 4096 &micro, g/mL). Synergism was observed against standard C. albicans (CA) and C. tropicalis (CT) strains and with the root extract against the CT isolate. The leaf extract inhibited the morphological transition of all strains while the root extract inhibited only CT strains.

The frequency of Alzheimer's disease (AD) is growing rapidly with longer life expectancy and the consequent increase of people with a high risk of neurodegenerative diseases. Anacardic acid (AA) has several pharmacological actions, such as antioxidants, anticholinesterase, and anti-inflammatory, which are related to the protection against aging disorders. Also, the metals copper and zinc are co-factors of antioxidant enzymes that can be associated with AA to improve brain-protective action. This study aimed to evaluate the potential of AA metal complexes using copper and zinc chelators to produce potential agents against Alzheimer's disease. For this purpose, Cu and Zn were linked to AA in the ratio of 1:1 in a basic medium. The complexes' formation was confirmed by ultraviolet and visible spectroscopy. The toxicity was evaluated in the zebrafish model, and other information related to AD was obtained using the zebrafish model of anxiety. AA-Zn and AA-Cu complexes showed better antioxidant action than free AA. In the anti-AChE activity, AA was like the AA-Cu complex. In models using adult zebrafish, no toxicity for AA complexes was found, and in the locomotor model, AA-Cu demonstrated possible anxiolytic action. In in silico experiments comparing AA and AA-Cu complex, the coupling energy with the enzyme was lower for the AA-Cu complex, showing better interaction, and also the distances of the active site amino acids with this complex were lower, similar to galantamine, the standard anti-AChE inhibitor. Thus, AA-Cu showed interesting results for more detailed study in experiments related to Alzheimer's disease.

Mimosa tenuiflora (Willd.) Poiret, popularly known in Brazil as "jurema-preta" is widely used against bronchitis, fever, headache and inflammation. Its antioxidant, anti-inflammatory and antinociceptive potential has already been reported. To assess the orofacial antinociceptive effect of M. tenuiflora, ethanolic extracts of M. tenuiflora (leaves, twigs, barks and roots) were submitted to in vitro tests of antioxidant activity. The extract with the highest antioxidant potential was partitioned and subjected to preliminary chemical prospecting, GC-MS, measurement of phenolic content and cytotoxicity tests of the fraction with the highest antioxidant activity. The nontoxic fraction with the highest antioxidant activity (FATEM) was subjected to tests of acute and chronic orofacial nociception and locomotor activity. The possible mechanisms of neuromodulation were also assessed. The EtOAc fraction, obtained from the ethanolic extract of M. tenuiflora barks, was the one with the highest antioxidant potential and nontoxic (FATEM), and Benzyloxyamine was the major constituent (34.27%). FATEM did not alter the locomotor system of mice and reduced significantly the orofacial nociceptive behavior induced by formalin, glutamate, capsaicin, cinnamaldehyde or acidic saline compared to the control group. FATEM also inhibited formalin- or mustard oil-induced temporomandibular nociception. In addition, it also reduced mustard oil-induced orofacial muscle nociception. However, FATEM did not alter hypertonic saline-induced corneal nociception. Neuropathic nociception was reversed by treatment with FATEM. The antinociceptive effect of FATEM was inhibited by naloxone, L-NAME and glibenclamide. FATEM has pharmacological potential for the treatment of acute and neuropathic orofacial pain and this effect is modulated by the opioid system, nitric oxide and ATP-sensitive potassium channels. These results lead us to studies of isolation and characterization of bioactive principles.

The level of acetylcholine, a neurotransmitter essential for processing memory and learning, is lower in the brains of patients with Alzheimer’s disease due to the higher concentration of the enzyme acetylcholinesterase. The main compounds used for Alzheimer’s treatment are acetylcholinesterase inhibitors. Quercetin coordination complexes with the metal ions Cu+2, Zn+2, Ni+2, Co+2, and Fe+2 were synthesized to investigate their potential use against Alzheimer’s disease, by evaluating the inhibition of acetylcholinesterase in vitro and in silico, as well as the antioxidant activity, toxicity, and anxiolytic action in the zebrafish (Danio rerio) model. The organic complexes were characterized by UV-Vis and FT-IR. The spectral information suggested that coordination of metals occurs with the carbonyl group and OH linked to the C-3 carbon of quercetin. The quercetin-Fe (QFe) complex presented the best antioxidant and antiacetylcholinesterase actions, and these results were confirmed by molecular docking. In the toxicity and locomotor evaluation, the quercetin molecules and the synthesized complexes, mainly QCu and QZn derivatives, showed the highest degree of inhibition of the fish’s locomotor activity, suggesting a possible anxiolytic action. Then, quercetin complexes with metals, mainly with Fe+2, represent valuable compounds and deserve more investigation as promising agents against Alzheimer’s disease.

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.

Background: Miconia albicans is a vegetable widely used in folk medicine as an alternative for the treatment of pain and inflammation. This study aimed to evaluate the chemical profile and anxiolytic- and anticonvulsant-like effects of the aqueous extract M. albicans leaves (CAVEL) in adult zebrafish. Materials and Methods: The antioxidant activity, chemical prospecting, and toxicity tests were performed. Then, the anxiolytic- and anticonvulsant-like effects were investigated in adult zebrafish. Results: It was detected the presence of flavonoids, xanthones, besides alkaloids, flavonoids, and polyphenols in CAVEL. Eighteen polyphenols and nine flavonoids were identified in CAVEL. CAVEL showed antioxidant activity and no cytotoxic potential. The effects of CAVEL in adult zebrafish were dependent on the route of administration: CAVEL (Per os [p.o.] and intraperitoneal [i.p.]) did not alter the locomotion of the animals, presented anxiolytic-like effect (p.o. and i.p.) and delayed anticonvulsant-like effect (p.o.). The anxiolytic-like effect was prevented by GABAergic receptor antagonist. M. albicans has pharmacological potential for the treatment of anxiety and anticonvulsant and these results support studies of isolation and characterization of bioactive principles. Conclusion: M. albicans has pharmacological potential for the treatment of anxiety and anticonvulsant and these results support studies of isolation and characterization of bioactive principles.

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.

Breadfruit (Artocarpus altilis) is a staple food in tropical regions and has several uses. The aim of this study was to establish the nutraceutical potential of an enriched protein fraction of breadfruit pulp (PFBp). PFBp was characterized by Fourier transform infrared spectroscopy, electrophoresis, zymography, thin-layer chromatography, and mass spectrometry. PFBp toxicity was assessed in vitro and in vivo. Its pharmacological effects were determined using zebrafish anxiety models, open field test, and light/dark test. PFBp is rich in essential amino acids (49.59 g/100 g), predominantly lysine and leucine. It contains proteases, including cysteine proteases and three major proteins (20–30 kDa). PFBp was not cytotoxic and showed ion-chelating antioxidant activity. It induced anxiolysis in zebrafish anxiety models. This effect was mediated by the serotoninergic system, mainly, 5-HTR1A, 5-HTR2C, and 5-HTR3. PFBp is a natural nutraceutical product. As a food supplement, PFBp could improve and sustain mental health.

Pitaya is a Cactacea with potential for economic exploitation, due to its high commercial value and its functional components – such betalains, oligosaccharides and phenolic compounds. Although the biological activities of pitaya have been studied using in vivo and in vitro models (anti-inflammatory and antiproliferative activities, as example), its anxiolytic-like effect is still unexplored. Therefore, the aim of this work was to perform a characterization of pulp and peel of pitaya (Hylocereus polyrhizus (F.A.C. Weber) Britton & Rose) using UPLC-QTOF-MSE, and to assess its toxicity and anxiolytic-like effect in adult zebrafish (Danio rerio). The results showed 16 and 15 compounds (in pulp and peel, respectively), including maltotriose, quercetin-3-O-hexoside, and betalains, putatively identified by UPLC-QTOF-MSE. Thus, pitaya pulp and peel showed no toxicity in both models tested (Vero cell lines and zebrafish model, LC50 ˃ 1 mg/mL); and a significant anxiolytic activity, since the treated fish reduced the permanence in the clear zone (Light & Dark Test) compared to that in the control, exhibiting anxiolytic-simile effect of diazepam. However, these effects were reduced by pre-treatment with the flumazenil suggesting that the pulp and peel of pitaya are anxiolytics agents mediated via the GABAergic system. These findings suggested that H. polyrizhus has the potential of developing an alternative plant-derived anxiolytic therapy. In addition, pitaya peel (which is a waste in the food industry) should be regarded as a valuable product, which has the potential as an economic value-added ingredient for anxiety disorders.

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.

This study aimed to evaluate the antinociceptive effect of sulphated polysaccharide from the marine algae Hypnea pseudomusciformis (PLS) using rodent models of orofacial pain. Acute pain was induced by formalin, capsaicin, cinnamaldehyde, acidified saline or glutamate (cutaneous modes) and hypertonic saline (corneal model). In one experiment, animals were pretreated with ruthenium red, glibenclamide, naloxone, L-NAME, methylene blue or ketamine to investigate the mechanism of antinociception. In another experiment, animals pretreated with PLS or saline were submitted to the temporomandibular joint formalin test. In yet another, animals were submitted to craniofacial pain induced by mustard oil. Motor activity was evaluated with the open-field test. Cytotoxicity and antioxidant activities were also assessed. Pre-treatment with PLS significantly reduced nociceptive behavior associated with acute pain. Antinociception was effectively reduced, but not inhibited, by ruthenium red and ketamine. L-NAME and glibenclamide enhanced the PLS effect. PLS antinociception was resistant to methylene blue, naloxone and heating. PLS presented no cytotoxicity or antioxidant properties. Our results confirm the potential pharmacological relevance of PLS as an inhibitor of orofacial nociception in acute pain probably mediated by glutamatergic, nitrergic, TRPs and K + ATP pathways.

Este trabalho reporta o potencial antibacteriano do cogumelo comestivel Pleurotus ostreatus . Extratos orgânicos, bem como β-glucânico e quitosânico, ambos nas concentracoes de 100, 300 e 500 ppm, foram submetidos a ensaios de disco-difusao contra quatro bacterias padroes: duas Gram positivas ( Staphylococcus aureus ATCC 25923 e Enterococcus faecalis ATCC 29212) e duas Gram negativas ( Escherichia coli ATCC 25922 e Pseudomonas aeruginosa ATCC 27853). Os extratos que apresentaram halo de inibicao (HI) do crescimento bacteriano iguais a 8 mm foram classificados como ativos. Dos extratos testados, o extrato β-glucânico se mostrou ativo, em ambas concentracoes, contra a bacteria Pseudomonas aeruginosa ATCC 27853 e na concentracao de 500 ppm contra as bacterias Staphylococcus aureus ATCC 25923 e Escherichia coli ATCC 25922. O extrato quitosânico apresentou atividade somente contra Pseudomonas aeruginosa ATCC 27853 na concentracao de 500 ppm. Estes resultados sao considerados promissores, pois apontam o extrato β-glucânico com potencial contra bacterias Gram positivas e Gram negativas. Futuros estudos bioguiados sob a acao antibacteriana desse extrato devem ser realizados para producao, purificacao e caracterizacao fisico-quimica do constituinte bioativo de interesse farmacologico.