Evaluation of Gastroprotective Activity of Linoleic Acid on Gastric Ulcer in a Mice Model.

BACKGROUND: Gastric ulcer has been a major cause of morbidity and mortality worldwide, and it has been linked to factors such as nutritional deficiency, smoking, stress, and continuous intake of non-steroidal antiinflammatory drugs (NSAIDs). The search for new anti-ulcer therapeutic agents has been the subject of several studies. Recently, the gastroprotective effect of Celtis iguanaea has been reported, with linoleic acid (LA) responsible for many of the therapeutic effects of this medicinal plant. AIMS: This study aims to investigate the gastroprotective activity and the possible mechanisms in which LA may be involved through different experimental assays in mice. METHODS: The gastroprotective activity of LA was evaluated in the ulcer induced by indomethacin, HCl/EtOH, hypothermic-restraint stress and pyloric ligation. For the investigation of gastroprotective mechanisms, the quantification of the volume (mL), pH and total acidity of gastric secretion were considered. RESULTS: The oral administrations of 25 mg/kg, 50 mg/kg or 100 mg/kg of body weight of LA were capable of protecting the gastric mucosa against HCl/ethanol (10 mL/kg p.o.), and oral/intraduodenal treatment administrations of 50 mg/kg LA showed protection from ulcers induced by indomethacin, hypothermic-restraint stress and pyloric ligation. CONCLUSION: The results of this study show the gastroprotective role of LA in gastric mucosal damage induced by all assayed distresses. The observed gastroprotection possibly occurs due to the mediated increase of mucosal defensive factors.

Mechanisms involved in the antinociceptive and anti-inflammatory effects of a new triazole derivative: 5-[1-(4-fluorophenyl)-1H-1,2,3-triazol-4-yl]-1H-tetrazole (LQFM-096).

The aim of this study was to design, synthesize and evaluate the potential analgesic and anti-inflammatory effects of 5-[1-(4-fluorphenyl)-1H-1,2,3-triazol-4-yl]-1H-tetrazole-(LQFM-096: a new triazole compound) as well as to elucidate its possible mechanisms of action. The oral administration of LQFM-096 (10, 20 or 40 mg/kg) decreased the number of writhing in mice. At the dose of 20 mg/kg, LQFM-096 reduced the licking time at both neurogenic and inflammatory phases of the formalin test. Pretreatment with naloxone (3 mg/kg) and glibenclamide (3 mg/kg) attenuated the antinociceptive effect of LQFM-096 in the first phase of the formalin test. At the dose of 20 mg/kg, LQFM-096 also decreased the licking time in the acidified saline-induced and capsaicin-induced nociception. This effect was blocked by naloxone (3 mg/kg) pretreatment prior to the administration of LQFM-096. In addition, LQFM-096 inhibited hyperalgesia induced by carrageenan and PGE2. Naloxone (3 mg/kg) attenuated the effect of LQFM-096 through disinhibition of PGE2-induced hyperalgesia. The anti-inflammatory effect of LQFM-096 was demonstrated in carrageenan-induced oedema or pleurisy as well as CFA-induced arthritis. The hyperalgesia and cellular migration in CFA-induced arthritis were reduced significantly. Altogether, these findings suggest antinociceptive effect of LQFM-096 and implicate the modulation of ASICs/TRPV1 channels by opioid/KATP pathway. The anti-inflammatory effect of LQFM-096 was mediated by a reduction in oedema, leukocytes migration, TNF-α, PGE2 levels and myeloperoxidase activity.

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-1ß 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.

A new piperazine derivative: 1-(4-(3,5-di-tert-butyl-4-hydroxybenzyl) piperazin-1-yl)-2-methoxyethan-1-one with antioxidant and central activity.

In the scope of a research program aimed at developing new drugs for the treatment of central nervous system diseases, we describe herein the synthesis and pharmacological evaluation of 1-(4-(3,5-di-tert-butyl-4-hydroxybenzyl) piperazin-1-yl)-2-methoxyethan-1-one (LQFM180). This compound showed antioxidant activity in two models, electroanalytical assays, and DPPH activity. Moreover, in behavioral tests as the open field test LQFM180 (9.4, 18.8, and 37.6 mg/kg, per oral (p.o.)), we detected anxiolytic-like activity. In the sodium pentobarbital-induced sleep test, LQFM180, in all doses, decreased the latency to sleep and increased sleep duration, indicating central depressant activity; moreover, in the chimney test, LQFM180 did not alter motor activity. LQFM180 (18.8 mg/kg, p.o.) increased the time and number of entries on open arms in the elevated plus maze test, suggesting anxiolytic-like activity, which was reversed by NAN-190 and p-chlorophenylalanine, indicating a role of the serotonergic pathway on this effect. In the forced swimming test, LFQM180 (18.8 mg/kg, p.o.) decreased immobility time, suggesting antidepressant-like activity, which was reversed by monoaminergic antagonists, indicating a role for the serotonergic, noradrenergic, and dopaminergic pathways. Competition binding assays showed that LQFM180 was able to bind to the α1B, 5-HT1A, and D2 receptors, however, within the low micromolar range. We conclude that LQFM180 should be considered as a scaffold for drug candidate development.

Potential anti-inflammatory effect of LQFM-021 in carrageenan-induced inflammation: The role of nitric oxide.

The pyrazole compound LQFM-021 exhibits vasorelaxant, antinociceptive and anti-inflammatory activities. Furthermore, it has low toxicity, indicating that this compound may be considered to be a good prototype for the development of new analgesic/anti-inflammatory drugs. Therefore, the aim of this study was to investigate the potential anti-inflammatory activity of LQFM-021 using a model of carrageenan-induced inflammation as well as the mechanism of action and role of nitric oxide in this effect. Acute treatments with LQFM-021 (30 and 60 mg/kg p.o.) reduced paw edema formation dose-dependently 2 h after carrageenan injection. In the carrageenan-induced pleurisy test, LQFM-021 (30 mg/kg p.o.) reduced the leukocyte (polymorphonuclear) count in the pleural cavity, as well as decreased protein extravasation and myeloperoxidase activity. This dose of LQFM-021 increased the NO (nitrite/nitrate) and IL-4 levels and decreased the TNF-α and IL-1ß levels in the pleural cavity. Moreover, pre-treatment with L-NAME reversed the effect of LQFM-021 on NO, leukocyte migration, and the TNF-α and IL-1ß levels. Additionally, we observed that LQFM-021 showed weak inhibitory activity on cyclooxygenases, but reduced the PGE2 levels in the pleural cavity. Immunoblot analyses showed that LQFM-021 promoted a decrease in COX-2 levels and increase in iNOS levels. In conclusion, we demonstrated that LQFM-021 has marked anti-inflammatory activity by reducing polymorphonuclear recruitment, which is associated with the inhibition of the production of inflammatory cytokines and eicosanoids. In addition, we found that the synthase/release of nitric oxide promoted by LQFM-021 is essential for the anti-inflammatory effect observed.

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.

The gastroprotective effect of Memora nodosa roots against experimental gastric ulcer in mice.

Memora nodosa is popularly known as "caroba" and widely found in the Cerrado regions of Brazil. In traditional medicine, the leaves and stems are used for the healing of external ulcer and the roots for abdominal pain. This study investigated the effect of ethanolic roots extract of Memora nodosa (EMN) on the gastric mucosa of mice. In the indomethacin induced gastric ulcer model, the treatments of the animals with EMN at doses of 100, 300 and 1000 mg/kg, p.o., markedly reduced the index of lesions. In the gastric ulcer models induced by ethanol and cold restraint-stress the previous treatment with EMN at dose of 300 mg/kg showed 69% and 43% of protection, respectively. Seven days after food-restriction, the animals treated with EMN (300 mg/kg p.o.) showed reduction in the index of lesion by 65% as compared to control group. The intraduodenal administration of EMN (300 mg/kg) did not alter the gastric acid secretion parameters. The treatment with EMN (300 mg/kg p.o.) did not alter glutathione levels (GSH), but showed an increase of adhered gastric mucus as compared to the control group with lesion. These results showed that EMN has gastroprotective activity probably due with an increase of adhered gastric mucus.

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.

Treatment of anxiety and depression: medicinal plants in retrospect.

Anxiety and depression are complex heterogeneous psychiatric disorders and leading causes of disability worldwide. This review summarizes reports on the fundamentals, prevalence, diagnosis, neurobiology, advancement in treatment of these diseases and preclinical assessment of botanicals. This review was conducted through bibliographic investigation of scientific journals, books, electronic sources, unpublished theses and electronic medium such as ScienceDirect and PubMed. A number of the first-line drugs (benzodiazepine, azapirone, antidepressant tricyclics, monoamine oxidase inhibitors, serotonin selective reuptake inhibitors, noradrenaline reuptake inhibitors, serotonin and noradrenaline reuptake inhibitors, etc.) for the treatment of these psychiatric disorders are products of serendipitous discoveries. Inspite of the numerous classes of drugs that are available for the treatment of anxiety and depression, full remission has remained elusive. The emerging clinical cases have shown increasing interests among health practitioners and patients in phytomedicine. The development of anxiolytic and antidepressant drugs of plant origin takes advantage of multidisciplinary approach including but not limited to ethnopharmacological survey (careful investigation of folkloric application of medicinal plant), phytochemical and pharmacological studies. The selection of a suitable plant for a pharmacological study is a basic and very important step. Relevant clues to achieving this step include traditional use, chemical composition, toxicity, randomized selection or a combination of several criteria. Medicinal plants have been and continue to be a rich source of biomolecule with therapeutic values for the treatment of anxiety and depression.