Daiany Priscilla Bueno da Silva

Involvement of the NO/cGMP/KATP pathway in the antinociceptive effect of the new pyrazole 5-(1-(3-fluorophenyl)-1H-pyrazol-4-yl)-2H-tetrazole (LQFM-021)

The pyrazol compounds are known to possess antipyretic, analgesic and anti-inflammatory activities. This study was conducted to investigate the peripheral antinociceptive effect of the pyrazole compound 5-(1-(3-Fluorophenyl)-1H-pyrazol-4-yl)-2H-tetrazole (LQFM-021) and involvement of opioid receptors and of the NO/cGMP/K(ATP) pathway. The oral treatments in mice with LQFM-021 (17, 75 or 300 mg/kg) decreased the number of writhing. In the formalin test, the treatments with LQFM-021 at doses of 15, 30 and 60 mg/kg reduced the licking time at both neurogenic and inflammatory phases of this test. The treatment of the animals with LQFM-021 (30 mg/kg) did not have antinociceptive effects in the tail-flick and hot plate tests. Furthermore, pre-treatment with naloxone (3 mg/kg i.p.), L-name (10 mg/kg i.p.), ODQ (10 mg/kg i.p.) or glibenclamide (3 mg/kg i.p.) antagonized the antinociceptive effect of LQFM-021 in both phases of the formalin test. In addition, it was also demonstrated that the treatments of mice with LQFM-021(15, 30 and 60 mg/kg) did not compromise the motor activity of the animals in the chimney test. Only the highest dose used in the antinociceptive study promoted changes in the open field test and pentobarbital-induced sleep test, thus ruling out possible false positive effects on nociception tests. Our data suggest that the peripheral antinociception effects of the LQFM-021 were mediated through the peripheral opioid receptors with activation of the NO/cGMP/KATP pathway.

Antinociceptive and anti-inflammatory effects of Memora nodosa and allantoin in mice

ETHNOPHARMACOLOGICAL RELEVANCE The leaves and stems bark of Memora nodosa (Silva Manso) Miers (Bignoniaceae) are used in Brazilian traditional medicine in the treatment of external ulcers and wounds; its roots are used to treat abdominal pain and scabies. AIM OF THE STUDY Our aim was to evaluate the antinociceptive and anti-inflammatory activities of Memora nodosa roots ethanolic extract (EMN) and allantoin, a secondary metabolite isolated from this plant. MATERIALS AND METHODS The EMN and allantoin antinociceptive activity were evaluated in mice using both chemical and heat-induced pain models such as acetic acid-induced writhing, formalin and tail-flick tests. In the formalin test, a pre-treatment with naloxone was used to verify an involvement of opioid receptor in the antinociceptive effect of EMN and allantoin. Pre-treatment with glibenclemide was used to verity an involvement of ATP-sensitive K(+)channel in the allantoin antinociceptive effect. EMN and allantoin anti-inflammatory activity were assessed by carrageenan-induced paw edema and pleurisy tests. RESULTS The treatment with EMN (250, 500 and 1000mg/kg, p.o.) inhibit the acetic acid and formalin (both phases)-induced nociception. However, just at doses 500 and 1000mg/kg increased the latency time in tail-flick test. These results suggest the involvement of both peripheral and central antinociceptive mechanisms. The treatment with allantoin (40, 60 and 80mg/kg p.o.) produced a dose-dependent antinociceptive effect in both phases of formalin-induced nociception test; allantoin (60mg/kg) was not able to increase the latency time in tail flick-test. The pre-treatment with naloxone completely reversed the EMN (1000mg/kg) and allantoin (60mg/kg) effect in the first phase of formalin test; and glibenclamide reversed the allantoin effect. The administration of EMN (250, 500 and 1000mg/kg) and allantoin (60mg/kg) showed significant anti-inflammatory activity in the whole carrageenan-induced paw edema. Furthermore, EMN and allantoin reduced the leukocytes migration and pleural exudate to the pleural cavity. CONCLUSION EMN have significant antinociceptive and anti-inflammatory effects, which appear to be, at least in part, due to the presence of allantoin. However, allantoin is not responsible for the EMN central antinociceptive activity. Allantoin has peripheral antinociceptive activity that involves the opioid receptor and ATP-sensitive K(+)channels. Opioid receptors are also involved in the EMN antinociceptive activity. These findings support the use of Memora nodosa in popular medicine and demonstrate that this plant has therapeutic potential for the development of antinociceptive and anti-inflammatory phytomedicines.

Anxiolytic-like effect of 2-(4-((1-phenyl-1H -pyrazol-4-yl)methyl)piperazin-1-yl)ethan-1-ol is mediated through the benzodiazepine and nicotinic pathways

In this study, we proposed the design, synthesis of a new compound 2‐(4‐((1‐phenyl‐1H‐pyrazol‐4‐yl)methyl)piperazin‐1‐yl)ethan‐1‐ol (LQFM032), and pharmacological evaluation of its anxiolytic‐like effect. This new compound was subjected to pharmacological screening referred to as Irwin test, prior to sodium pentobarbital‐induced sleep, open‐field and wire tests. The anxiolytic‐like effect of this compound was evaluated using elevated plus maze and light–dark box tests. In addition, the mnemonic activity was evaluated through step‐down test. In sodium pentobarbital‐induced sleep test, LQFM032 decreased latency and increased duration of sleep. In the open‐field test, LQFM032 altered behavioral parameter, that suggested anxiolytic‐like activity, as increased in crossings and time spent at the center of open field. In the plus maze test and light–dark box test, the LQFM032 showed anxiolytic‐like activity, increased entries and time spent on open arms, and increased in number of transitions and time spent on light area, respectively. Those effects was antagonized by flumazenil but not with 1‐(2‐Methoxyphenyl)‐4‐(4‐phthalimidobutyl)piperazine (NAN‐190). The LQFM032 did not alter mnemonic activity. Moreover, the anxiolytic‐like activity of LQFM032 was antagonized by mecamylamine. In summary, LQFM032 showed benzodiazepine and nicotinic pathways mediated anxiolytic‐like activity without altering the mnemonic activity.

Design, synthesis and pharmacological evaluation of new anti-inflammatory compounds.

Inflammatory diseases and pain are among the main problems that significantly influence the lifestyle of millions of people and existing therapies are not always effective and can cause several adverse effects. In this context, the molecular modifications or synthesis of compounds continue being the best strategies for the identification of new compounds for the treatment of pain and inflammation. The aim of this study was to evaluate the analgesic and anti-inflammatory activities of new analogues of pyrazole compounds containing subunits N-phenyl-1-H-pirazoles and 1,3,4-oxadiazole-2(3H)-thione, LQFM-146, LQFM-147 and LQFM-148. In the acetic acid-induced abdominal writhing test, treatments with LQFM-146, LQFM-147 or LQFM-148 at doses 89, 178 and 356µmol/kg p.o. reduced the abdominal writhing in a dose-dependent manner. In the formalin test, these compounds at dose 178µmol/kg p.o. reduced the licking time only in inflammatory phase of this test, suggesting an antinociceptive effect dependent of the anti-inflammatory effect. The treatment with the three compounds in intermediate dose (178µmol/kg p.o.) reduced the edema at all tested time points in the carrageenan-induced paw edema test and reduced polymorphonuclears cell migration, activity myeloperoxidase and TNF-α levels in the carrageenan-induced pleurisy test. Our date suggest that the new compounds LQFM-146, LQFM-147 and LQFM-148 possess satisfactory anti-inflammatory and antinociceptive effects that involves the reduction of pro-inflammatory cytokines and inhibition of the myeloperoxidase enzyme.

Anti-nociceptive and anti-inflammatory activities of 4-[(1-phenyl-1H-pyrazol-4-yl) methyl] 1-piperazine carboxylic acid ethyl ester: A new piperazine derivative.

Piperazine compounds possess anti-infective, anti-carcinogenic, anxiolytic, hypotensive, anti-hypertensive and vasorelaxant properties and are attractive candidates for the development of new analgesic and anti-inflammatory drugs. This study investigates the anti-nociceptive and anti-inflammatory effects of piperazine derivative 4-[(1-phenyl-1H-pyrazol-4-yl) methyl]1-piperazine carboxylic acid ethyl ester (LQFM-008) and the involvement of the serotonergic pathway. In the formalin test, treatments with LQFM-008 (15 and 30mg/kg p.o.) reduced the licking time in both neurogenic and inflammatory phases of this test. In the tail flick and hot plate tests, LQFM008 treatment (15 and 30mg/kg p.o.) increased latency to thermal stimulus, suggesting the involvement of central mechanisms in the anti-nociceptive effect of LQFM-008. In the carrageenan-induced paw edema test, LQFM-008 (p.o.) at the doses of 15 and 30mg/kg reduced the edema at all tested time points, while the dose of 7.5mg/kg reduced the edema only for the first hour. LQFM-008 (30mg/kg p.o.) reduced both cell migration and protein exudation in the carrageenan-induced pleurisy test. Furthermore, pre-treatment with NAN-190 (0.6mg/kgi.p.) and PCPA (100mg/kgi.p.) antagonized the anti-nociceptive effect of LQFM-008 in both phases of the formalin test. Our data suggest that LQFM-008 possesses anti-inflammatory and anti-nociceptive effects mediated through the serotonergic pathway.

Chemical characterization and pharmacological assessment of polysaccharide free, standardized cashew gum extract (Anacardium occidentale L.)

ETHNOPHARMACOLOGICAL RELEVANCE The cashew gum (Anacardium occidentale L.) is used in traditional Brazilian medicine in the treatment of inflammatory conditions, asthma, diabetes, and gastrointestinal disturbances. AIM OF THE STUDY In the present study, we aimed at forming a chemical characterization and investigation of the antinociceptive and anti-inflammatory activities of the aqueous extract of cashew gum without the presence of polysaccharides in its composition (CGE). MATERIALS AND METHODS The CGE was obtained after the precipitation and removal of polysaccharides through the use of acetone. After, the acetone was removed by rotaevaporation, and the concentrated extract was lyophilized. The chemical characterization of CGE was performed by liquid chromatography mass spectrometry (LC-MS) and tandem mass spectrometry (MS/MS) analyses. Mice were used for the evaluation of the antinociceptive and anti-inflammatory activities. CGE was analyzed via the Irwin test, acetic acid-induced writhing test, formalin-induced pain test, and carrageenan-induced paw edema test. The motor activity or probable sedation was verified through the chimney, open-field, and sodium pentobarbital-induced sleep tests. We investigated if the analgesic and anti-inflammatory effects of CGE depend of reduction in PGE2 levels, were performed the carrageenan or PGE2-induced hyperalgesia tests. RESULTS The chemical characterization of CGE showed the presence of anacardic acids as the predominant phytoconstituents. The treatment with CGE (75, 150, and 300mg/kg, p.o.) inhibited the number of writhing in a dose-dependent manner. With an intermediate dose, CGE did not cause motor impairment with the chimney test or alterations in either the open-field or sodium pentobarbital-induced sleep. In the formalin-induced pain test, CGE (150mg/kg, p.o.) produced an antinociceptive effect only in the first phase of the test, suggesting anti-inflammatory activity. With the same dosage, CGE also reduced the carrageenan-induced paw edema at all hours of the test, confirming its anti-inflammatory effect. Furthermore, CGE (150mg/kg, p.o.) presented an antihyperalgic effect at all hours of the carrageenan-induced hyperalgesia test. However, this dose of CGE was not able to reduce the hyperalgesia induced by PGE2, suggesting that the anti-inflammatory effect of this extract depends on the reduction in the PGE2 levels. CONCLUSION The anacardic acids are the predominant phytoconstituents identified in the CGE. The action mechanisms of CGE suggest the reduction in the PGE2 levels. These findings support the use of cashew gum in popular medicine and demonstrate that part of its antinociceptive and anti-inflammatory effects should also be attributed to the presence of anacardic acids in its composition, independent of the presence of polysaccharides.The cashew gum (Anacardium occidentale L.) is used in Brazilian traditional medicine in the treatment of inflammatory conditions, asthma, diabetes, and gastrointestinal disturbs.The present study was aimed the chemical characterization and the investigation of the antinociceptive and anti-inflammatory activities of cashew gum aqueous extract without the presence of polysaccharides in its composition (CGE).The CGE was obtained after precipitation and removal of polysaccharides using acetone. Acetone solvent was removed from the CGE by rotaevaporation and subsequently this concentrated extract was lyophilized. The chemical characterization of CGE was performed by Liquid Chromatography Mass Spectrometry (LC-MS) and Tandem Mass Spectrometry (MS/MS) analysis. Mice were used for the evaluation of the antinociceptive and anti-inflammatory activities. CGE was analyzed in Irwin test, acetic acid-induced writhing test, formalin-induced pain test and carrageenan-induced paw edema and hyperalgesia tests. Also, the motor activity or probable sedation was verified in chimney test, open-field, and sodium pentobarbital-induced sleep tests. In the investigation of the action mechanisms of CGE, were performed the PGE2-induced hyperalgesia test to investigate the possible involvement of an inhibition of PGE2 synthesis in the analgesic and anti-inflammatory effects of CGE.The chemical characterization of CGE showed the presence of anacardic acids as predominant phytoconstituents. The treatment with CGE (75, 150 and 300mg/kg, p.o.) inhibited the number of writhing in a dose-dependent manner. In intermediate dose, CGE did not cause motor impairment in chimney test or alterations in open-field and sodium pentobarbital-induced sleep. In the formalin-induced pain test, CGE (150mg/kg, p.o.) produced antinociceptive effect only in the first phase of the test, suggesting an anti-inflammatory activity. In the same dose, CGE also reduced the carrageenan-induced paw edema at all hours of the test, confirm its anti-inflammatory effect. Furthermore, CGE (150mg/kg, p.o.) presented antihyperalgic effect in at all hours of the carrageenan-induced hyperalgesia test. However, this some dose of CGE was not able to reduce the hyperalgesia induced by PGE2, suggesting that the anti-inflammatory effect of this extract depends on the reduction in the PGE2 levels.The anacardic acids are the predominant phytoconstituents identified in the CGE, which has significant antinociceptive and anti-inflammatory effects in different experimental models. The action mechanisms of CGE suggest the reduction in the PGE2 levels. These findings support the use of cashew gum in popular medicine and demonstrate that part of its antinociceptive and anti-inflammatory effects should also be attributed to the presence of anacardic acids in its composition and independent of the presence of polysaccharides. Moreover, this study showed therapeutic potential of cashew gum for the development of analgesic and anti-inflammatory phytomedicines.

Molecular docking and pharmacological/toxicological assessment of a new compound designed from celecoxib and paracetamol by molecular hybridization

Nonsteroidal anti-inflammatory drugs are commonly used worldwide; however, they have several adverse effects, evidencing the need for the development of new, more effective and safe anti-inflammatory and analgesic drugs. This research aimed to design, synthesize and carry out a pharmacological/toxicological investigation of LQFM-102, which was designed from celecoxib and paracetamol by molecular hybridization. To evaluate the analgesic effect of this compound, we performed formalin-induced pain, hot plate and tail flick tests. The anti-inflammatory effect of LQFM-102 was evaluated in carrageenan-induced paw oedema and pleurisy tests. The biochemical markers indicative of toxicity—AST, ALT, GSH, urea and creatinine—as well as the index of gastric lesion after prolonged administration of LQFM-102 were also analyzed. In addition, the interaction of LQFM-102 with COX enzymes was evaluated by molecular docking. In all experimental protocols, celecoxib or paracetamol was used as a positive control at equimolar doses to LQFM-102. LQFM-102 reduced the pain induced by formalin in both phases of the test. However, this compound did not increase the latency to thermal stimuli in the hot plate and tail flick tests, suggesting an involvement of peripheral mechanisms in this effect. Furthermore, LQFM-102 reduced paw oedema, the number of polymorphonuclear cells, myeloperoxidase activity and TNF-α and IL-1β levels. Another interesting finding was the absence of alterations in the markers of hepatic and renal toxicity or lesions of gastric mucosa. In molecular docking simulations, LQFM-102 interacted with the key residues for activity and potency of cyclooxygenase enzymes, suggesting an inhibition of the activity of these enzymes.

Effect of allantoin on experimentally induced gastric ulcers: Pathways of gastroprotection

Abstract Gastric ulcer affects people worldwide, and its inefficacy and recurrence have fueled the search for new therapeutic strategies. Despite the well‐known use of allantoin in medicines and cosmetic products, its effect has not yet been studied with regard to gastric ulcer. Hence, the aim of the present study was to explore the pharmaco‐mechanistic efficacy of allantoin against commonly harmful agents that cause injuries to the stomach. Ethanol, indomethacin, and stress‐induced gastric ulcer models were adopted, in addition to pylorus ligature, a quantification of vascular permeability, glutathione (GSH), gastric adhered mucus, prostaglandin (PGE2), pro‐inflammatory cytokines levels, myeloperoxidase (MPO), and catalase (CAT) activities. The gastric lesions were examined by gross, histological, and ultrastructural features. The results showed that treatment with allantoin (60 mg/kg, per oral) reduced the gastric ulcer formation in all models. Furthermore, allantoin reduced the parameters of gastric acid secretion and attenuated both the vascular permeability and MPO activity. The levels of pro‐inflammatory cytokines were also reduced, accompanied by a restoration of CAT activity and GSH levels. Notably, allantoin treatment preserved the gastric‐adhered mucus and PGE2 levels after ethanol administration. Microscopic and ultrastructural analysis revealed that allantoin maintained tissue integrity and prevented morphological changes in cells caused by ethanol. In summary, we demonstrated for the first time that allantoin possesses gastroprotective activity through anti‐inflammatory, anti‐oxidative, antisecretory, and cytoprotective mechanisms. The antisecretory and cytoprotective mechanisms are probably associated with an increase in PGE2 levels. Graphical abstract Figure. No caption available. HighlightsAllantoin promotes gastroprotective effects in mice.The possible mechanisms are through anti‐inflammatory, anti‐oxidative, antisecretory, and cytoprotective pathways.Histological and ultrastructural analysis suggest interference in gastric mucus production.

Monoamine Involvement in the Antidepressant-Like Effect of β-Caryophyllene

BACKGROUND Major depressive disorder is a psychiatric disorder that affects 4.4% of the population worldwide. Although the majority of antidepressant drugs ameliorate depressive symptoms, there is still a need for safer and more effective antidepressant. OBJECTIVE Evaluate the antidepressant-like activity of sesquiterpene compound β-caryophyllene (BCP) for the possible contribution of the monoamine and hippocampal levels of brain-derived neurotrophic factor (BDNF). METHODS Male albino Swiss mice were subjected to the forced swimming test after acute treatment and to the tail suspension test after repeated treatment. Hippocampal levels of BDNF were assayed by enzyme-linked immunosorbent assay. RESULTS The anti-immobility effect of BCP was reverted by pretreatment with an inhibitor of catecholamine synthesis α-methyl-p-tyrosine (100 mg/kg, i.p.), α2-adrenergic antagonist yohimbine (1 mg/kg, i.p.), and β-adrenergic antagonist propranolol (2 mg/kg, i.p.), but not by pretreatment with either α1-adrenergic antagonist prazosin (1 mg/kg, i.p.) or 5-HT1A antagonist NAN-190 (0.5 mg/kg, i.p.), thereby suggesting the involvement of α2 and β-adrenergic receptors, but not of the α1-adrenergic and 5-HT1A serotonergic receptors, in BCPs antidepressive-like activity. Furthermore, BCP increased BDNF levels in the hippocampus after 14 days of treatment. No treatments in this study altered locomotor activity in the open field test. CONCLUSION This study provides a new mechanism of BCP-induced antidepressant-like effect mediated by some sub-types of catecholaminergic neurotransmitter system that could be a candidate for clinical tests of new treatments for depressive disorders.

Tert-butyl 4-((1-phenyl-1H-pyrazol-4-yl) methyl) piperazine-1-carboxylate (LQFM104)– New piperazine derivative with antianxiety and antidepressant-like effects: Putative role of serotonergic system

The piperazine derivatives correspond to an extensive chemical class of compounds with numerous neuropharmacological activities, including antidepressant (e.g., nefazodone, trazodone) and anxiolytic (e.g., buspirone) properties. Therefore, aiming to identify a new antidepressant and antianxiety lead-compound, our group designed, synthesized, and investigated the effects of a new piperazine compound, namely, LQFM104, on the behavior of mice. Male albino Swiss mice were treated with LQFM104 prior to predictive behavioral tests as open field (OFT), elevated plus maze (EPM), forced swimming (FST), and tail suspension tests (TST). The participation of the serotonergic system was evaluated by pretreatment with a 5-HT1A antagonist receptor (WAY100635) and serotonin (5-HT) synthesis inhibitor (p-chlorphenylalanine, pCPA) before oral administration of LQFM104 and behavioral tests. The treatment with LQFM104 did not interfere with locomotor activity but revealed suggestive data of anxiolytic-like effects by the increase in the time spent in the center of the OFT. This activity was confirmed by the results obtained in the EPM, and it was abolished after pretreatment with WAY100635 and pCPA. The immobility time decreased in both the FST and TST. The antidepressant-like activity was completely abolished after WAY100635 pretreatment. Altogether, these data revealed that LQFM104 possesses anxiolytic and antidepressant-like properties in behavioral tests on mice, and these activities are possibly mediated, directly and/or indirectly, by serotonergic pathways.