Volatile oil of Croton zehntneri per oral sub-acute treatment offers small toxicity: perspective of therapeutic use

ABSTRACT Croton zehntneri Pax & K. Hoffm., Euphorbiaceae, or "canela-de-cunhé" is used in the Northeast Brazil to treat several diseases. Leaves and aerial parts of C. zehntneri are rich in volatile oil of high potential therapeutic. This study aimed to investigate volatile oil systemic toxicity after per oral treatment in rats. Volatile oil characterization (gas chromatography and mass spectrometry) showed 85.7% anethole and 4.8% estragole. Male Wistar rats (116-149 g) were treated with volatile oil (250 mg/kg p.o.) during ten weeks and evaluated for the following parameters: survival; food and water intake; body mass; absolute/relative organs weight; hemogram; plasma biochemical dosage; organs morphology. Volatile oil did not alter animal water and food consumption or the relative/absolute weight of most organs, but animals gained less weight. Volatile oil did not alter function biomarkers of pancreas, kidney, heart or liver, but increased plasma gamma-glutamyltranspeptidase (liver biomarker) and decreased uric acid (kidney biomarker). Although volatile oil had caused discrete morphological alterations in some organs, it did not induce architectural changes in these organs. In conclusion, the sub-acute per oral treatment with volatile oil no longer than ten weeks in rats offers small toxicity at doses below 250 mg/kg.

Purification and primary structure of a mannose/glucose-binding lectin from Parkia biglobosa Jacq. seeds with antinociceptive and anti-inflammatory properties.

Parkia biglobosa (subfamily Mimosoideae), a typical tree from African savannas, possess a seed lectin that was purified by combination of ammonium sulfate precipitation and affinity chromatography on a Sephadex G-100 column. The P. biglobosa lectin (PBL) strongly agglutinated rabbit erythrocytes, an effect that was inhibited by d-mannose and d-glucose-derived sugars, especially α-methyl-d-mannopyranoside and N-acetyl-d-glucosamine. The hemagglutinating activity of PBL was maintained after incubation at a wide range of temperature and pH and also was independent of divalent cations. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis, PBL exhibited an electrophoretic profile consisting of a single band with apparent molecular mass of 45 kDa. An analysis using electrospray ionization-mass spectrometry indicated that purified lectin possesses a molecular average mass of 47 562 ± 4 Da, and the analysis by gel filtration showed that PBL is a dimer in solution. The complete amino acid sequence of PBL, as determined using tandem mass spectrometry, consists of 443 amino acid residues. PBL is composed of a single non-glycosylated polypeptide chain of three tandemly arranged jacalin-related domains. Sequence heterogeneity was found in six positions, indicating that the PBL preparations contain highly homologous isolectins. PBL showed important antinociceptive activity associated to the inhibition of inflammatory process.

Comparative study of the anti-edematogenic effects of anethole and estragole.

BACKGROUND: Anethole and estragole are monoterpene position isomers and constituents of essential oils from aromatic plants and were used in this study with the aim of analyzing their anti-inflammatory activity. METHODS: The anti-edematogenic effects of anethole and estragole were evaluated through plethysmometry in Swiss mice. RESULTS: Anethole inhibited carrageenan-induced edema at doses of 3, 10 and 30 mg/kg from 60 to 240 min after induction. However, the inhibitory effects of estragole were observed only from 60 to 120 min at the two highest doses. Anethole and estragole similarly inhibited edema elicited by substance P, bradykinin, histamine and TNF-α but were different in the inhibition of serotonin-elicited edema. In addition, only estragole inhibited sodium nitroprusside-induced edema. CONCLUSIONS: Anethole and estragole showed different profiles in the anti-inflammatory response to substance P, bradykinin, histamine, serotonin and TNF-α NO is involved only in the inhibition mechanism of estragole.

Venom's antinociceptive property in the primitive ant Dinoponera quadriceps.

ETHNOPHARMACOLOGICAL RELEVANCE: In northeastern Brazil, Dinoponera (Ponerinae) ants macerate are used to treat ear ache and its sting, rheumatism, and back pain. Such a popular use is a relevant fact that called for experimental evaluation of the antinociceptive activity of Dinoponera venom. MATERIALS AND METHODS: Dinoponera quadriceps venom (DqV; 5-500 µg/kg; i.v.) or morphine (3.4 mg/kg; s.c.) were evaluated in mice models of nociception (n=8 animals/group). Negative controls received sterile saline (0.9% NaCl; i.v.). RESULTS: DqV showed 64% protein content and exhibited antinociceptive activity, without affecting motor function, in the tests: formalin (72%), writhing (52%), von Frey (71%) and hot plate (45%). The antinociceptive activity was abolished under protein denaturant conditions. CONCLUSIONS: This study provided the first demonstration of the antinociceptive property of Dinoponera quadriceps venom in mice models of chemical, mechanical and thermal nociception, corroborating the popular use and suggesting its potential therapeutic utilization in painful conditions.