Anita Oliveira Brito Pereira Bezerra Martins

Antiulcerogenic Activity of the Hydroalcoholic Extract of Leaves of Croton campestris A. St.-Hill in Rodents

Croton campestris A. St.-Hill., popularly known as “velame do campo,” is a species native to the savannah area of Northeast Brazil, which is used by traditional communities in folk medicine for variety of health problems, especially detoxification, inflammation, and gastritis. The hydroalcoholic extract of C. campestris leaves (HELCC) was assessed for its antiulcerogenic effect in gastric lesion models and effect on intestinal motility in mice, and possible mechanisms of action were examined. HELCC showed significant gastroprotective action in all models of gastric ulcer evaluated; the results suggest that this action probably involves the nitric oxide pathway. HELCC did not show alteration of intestinal motility in mice. It was also found that C. campestris represents a promising natural source with important biological potential, justifying some of its uses in folk medicine.

Potentiation of antibiotic activity by Passiflora cincinnata Mast. front of strains Staphylococcus aureus and Escherichia coli

The development of new drugs from plants is an interesting alternative approach to overcoming microbial resistance. Passiflora cincinnata shows resistance to diseases and pests and a higher concentration of chemical components that may be useful in the pharmaceutical industry. We investigated the potential antimicrobial and antibiotic-modifying activity of hydroalcoholic extracts of leaves, stems, bark, pulp and seeds of P. cincinnata. The extracts were prepared by homogenization of material in 50% ethanol. Minimum inhibitory concentration (MIC) was determined by the broth dilution method, and the bacterial strains tested were Staphylococcus aureus and Escherichia coli. Antibiotic-modifying activity was evaluated against the strains S. aureus 03 and E. coli 08, using a subinhibitory concentration of extract. The antibiotics tested were: amikacin, gentamicin, ampicillin, potassium benzylpenicillin and oxacillin. The extracts did not show antimicrobial activity of clinical relevance, where the MIC was equal to or greater than 1024 μg/mL. S. aureus showed 13 events, while E. coli showed only 4 events. Among these events, 14 involved synergistic activity, potentiating the effect of the antibiotics, and only 3 events demonstrated antagonistic activity toward ampicillin. Hydroalcoholic extracts are potential antimicrobial agents when combined with conventional drugs little utilized in in vivo treatment.

Enhancement of orofacial antinociceptive effect of carvacrol, a monoterpene present in oregano and thyme oils, by β-cyclodextrin inclusion complex in mice.

Orofacial pain is associated with diagnosis of chronic pain of head, face, mouth, neck and all the intraoral structures. Carvacrol, a naturally occurring isoprenoid with diverse class of biological activities including anti-inflammatory, analgesic, antitumor and antioxidant properties. Now, the antinociceptive effect was studied in mice pretreatment with carvacrol (CARV) and β-cyclodextrin complex containing carvacrol (CARV-βCD) in formalin-, capsaicin-, and glutamate- induced orofacial nociception. Mice were pretreated with vehicle (0.9% Nacl, p.o.), CARV (10 and 20mg/kg, p.o.), CARV-βCD (10 and 20mg/kg, p.o.) or MOR (10mg/kg, i.p.) before the nociceptive behavior induced by subcutaneous injections (s.c.) of formalin (20μl, 2%), capsaicin (20μl, 2.5μg) or glutamate (20μl, 25μM) into the upper lip respectively. The interference on motor coordination was determined using rotarod and grip strength meter apparatus. CARV-βCD reduced the nociceptive during the two phases of the formalin test, whereas CARV did not produced the reduction in face-rubbing behavior in the initial phase. CARV-βCD (20mg/kg, p.o.) produced 49.3% behavior pain while CARV alone at 20mg/kg, p.o, produced 28.7% of analgesic inhibition in the second phase of formalin test. CARV, CARV-βCD and Morphine (MOR) showed a significant reduction against nociception caused by capsaicin or glutamate injection. Thus the encapsulation of carvacrol in β-cyclodextrin can acts as a considerable therapeutic agent with pharmacological interest for the orofacial pain management.

Gastroprotective effect and mechanism of action of Croton rhamnifolioides essential oil in mice

BACKGROUND Croton rhamnifolioides Pax is a plant species that have been used in the folk medicine to treat ulcers, inflammations and hypertension. However, despite the relevant data obtained from ethnopharmacological studies, the pharmacological properties endorsing the efficacy of this plant to treat ulcer remain to be elucidated. HYPOTHESIS/PURPOSE The present study aimed to characterize the chemical profile and evaluate the gastroprotective activity of the essential oil obtained from C. rhamnifolioides Pax (OECC) in mice. METHODS The essential oil of Croton rhamnifolioides was obtained by hydrodistillation and analyzed by gas-phase chromatography coupled to mass spectrometry (GC/MS). The median lethal dose was determined employing an acute toxicity test. The gastroprotective activity of the OECC was investigated using animal models of gastric ulcer induced by the administration of absolute ethanol, acidified ethanol or indomethacin. Mechanisms of action were investigated using the physical barrier test and by in vivo evaluation of the involvement of the following molecular pathways: nitric oxide, ATP - dependent potassium channels, α2 - noradrenergic receptors, capsaicin - sensitive afferent neurons and opioid receptor. RESULTS We identified the presence of 21 compounds in OECC, including spathulenol and 1,8 - cineole as major constituents. In orally administered mice, OECC caused no significant toxicity. OECC significantly prevented gastric lesions in all mice models. The barrier test demonstrated that the gastroprotective activity of OECC occurs in a systemic dimension. Our results demonstrated that the gastroprotective effect of OECC involves mechanisms that are related to modulation of opioid receptors and nitric oxide. CONCLUSION In conclusion, OECC demonstrated significant gastroprotective activity associated with low toxicity, providing scientific evidences that C. rhamnifolioides have the potential for the development of new antiulcer drugs.

D-limonene exhibits superior antihyperalgesic effects in a β-cyclodextrin-complexed form in chronic musculoskeletal pain reducing Fos protein expression on spinal cord in mice

Chronic musculoskeletal pain is one of the main symptoms found in Fibromyalgia with unclear etiology and limited pharmacological treatment. The aim of this study was to complex LIM in β-cyclodextrin (LIM-βCD) and then evaluate its antihyperalgesic effect in an animal model of chronic musculoskeletal pain. Differential scanning calorimetry and scanning electron microscopy was used for the characterization of the inclusion complex. Male Swiss mice were used for experimental procedures where mechanical hyperalgesia, thermal hyperalgesia, muscular strength, Fos immunofluorescence was studied after induction of hyperalgesia. Mechanism of action was also investigated through tail flick test and capsaicin-induced nociception. Endothermic events and morphological changes showed that the slurry complex method was the best method for the complexation. After induction of hyperalgesia, the oral administration of LIM-βCD (50mg/kg) significantly increased the paw withdrawal threshold compared to uncomplexed limonene. Fos immunofluorescence showed that both compounds significantly decreased the number of Fos-positive cells in the dorsal horn. In nociceptive tests, FLU was able to reverse the antinociceptive effect of LIM-βCD. After intraplantar administration of capsaicin, LIM was able to significantly decrease time to lick. LIM-βCD has antihyperalgesic action superior to its uncomplexed form, with possible action in the dorsal horn of the spinal cord. These results suggest the possible applicability of LIM, uncomplexed or complexed with βCD, in conditions such as FM and neuropathic pain, for which there are currently only limited pharmacological options.

Evaluation of the antioxidant and gastroprotective activity and HPLC analysis of the hydroalcoholic extract of Tocoyena formosa leaves (Cham. & Schlecht) K. Schum

The peptic ulcer is a gastric disorder that affects millions of people and yet they cause many side effects. In this sense, natural products represent an important alternative to the discovery of compounds with gastroprotective activity. The present work has as its objective to evaluate the antioxidant and gastroprotective activity of the Hydroalcoholic Extract of Leaves from Tocoyena formosa (Cham. & Schlecht.) K. Schum (HELTF), this being much emphasized in traditional medicine for inflammatory morbidities and gastric symptoms. For the evaluation of the antioxidant activity, FRAP and DPPH tests were carried out, and for the evaluation of the gastroprotective activity, gastric lesion induction by ethanol, acidified ethanol, indomethacin and physical barrier tests were used. Antioxidant assay of HELTF revealed an EC50 of 558.66 μM FeSO4/g and IC50 of 189.78 μg/ml for FRAP and DPPH respectively. In gastroprotective, in ethanol model, all the doses presented significant activity in comparison to controls, however, in the gastric lesion induction test by acidified ethanol and indomethacin, only the dose of 200 mg/kg presented with significance. In the physical barrier test presented evidence that protection by the formation of a protective layer associated with mucus. Concluded, therefore, that HELTF possesses antioxidant and significate gastroprotective activity.

Chemical fingerprint, acute oral toxicity and anti-inflammatory activity of the hydroalcoholic extract of leaves from Tocoyena formosa (Cham. & Schlecht.) K. Schum

Inflammation is a protective response of the organism against damaging agents, this process is considered beneficial, however in some situations, this response can be damage when exacerbated effect are present. This claim objective to evaluate the qualitative and quantitative chemical profile, acute toxic and anti-inflammatory effects of the hydroalcoholic extract of leaves from Tocoyena formosa (Cham. & Schlecht.) K. Schum. (HELTF). Quantitative and qualitative phytochemical analysis was performed by HPLC-DAD and colorimetric assay. The topical anti-inflammatory activity was determined in Croton oil-induced ear edema assay and systemic activity was performed in vascular permeability, paw edema induced by carrageenan and dextran. Phytochemical analysis of leaves from HELTF showed presence of tannin, flavonoid, saponins an other that confirmed by HPLC analysis. The extract did not cause significant with LD50 greater than 5000 mg/kg and did not promote significate reduction in topical inflammatory process. However, HELTF demonstrate significant reduction of paw edema induced by carrageenan and dextran. The HELTF (200 mg/kg) reduced the protein/cell migration in the intradermal carrageenan-induced inflammation. Our results demonstrated that the first time the chemical profile and describe the effective action in systemic anti-inflammatory, antiedematogenic activity and low acute toxicity. This activity presents, supporting its traditional use. However, new studies are necessary for the detection and clarification of the possible mechanism of action.

EFEITOS DO ÓLEO ESSENCIAL DO Croton argyrophylloides NAS LESÕES GÁSTRICAS INDUZIDAS POR ETANOL E INDOMETACINA EM CAMUNDONGOS.

A ulcera peptica afeta milhoes de pessoas, suas recidivas sao elevadas e muitos medicamentos utilizados no tratamento apresentam efeitos adversos, por isso o estudo de plantas medicinais que tem acao protetora sobre o estomago assume grande importância na atualidade. Sobre o oleo essencial do Croton argyrophylloides (OECA) nao existem estudos em ulceras gastricas. O objetivo desse estudo foi avaliar o efeito do OECA sobre ulceras gastricas induzidas. E um estudo experimental com abordagem quantitativa. Foram utilizados camundongos Swiss no qual foram mantidos em jejum antes do experimento. Estes foram pre-tratados com administracao do OECA antes da inducao da ulcera por etanol e indometacina; foram laparatomizados para resseccao dos seus estomagos e retirada do muco.Os estomagos foram digitalizados para analise das lesoes. Concluimos que o OECA mostrou-se eficaz na reducao das lesoes gastricas associadas a administracao de etanol e indometacina por meio do aumento da producao de muco. ( http://dx.doi.org/10.14295/cad.cult.cienc.v13i2.686 )