Filicene obtained from Adiantum cuneatum interacts with the cholinergic, dopaminergic, glutamatergic, GABAergic, and tachykinergic systems to exert antinociceptive effect in mice.

In the present study, we describe the antinociceptive effect of filicene, a triterpene isolated from Adiantum cuneatum (Adiantaceae) leaves, in several models of pain in mice. When evaluated against acetic acid-induced abdominal constrictions, filicene (10, 30 and 60 mg/kg, i.p.) produced dose-related inhibition of the number of constrictions, being several times more potent [ID(50)=9.17 (6.27-13.18) mg/kg] than acetaminophen [ID(50)=18.8 (15.7-22.6) mg/kg], diclofenac [ID(50)=12.1(9.40-15.6) mg/kg] and acetylsalicylic acid [ID(50)=24.0(13.1-43.8) mg/kg] in the same doses as those used for the standard drugs. Filicene also produced dose-related inhibition of the pain caused by capsaicin and glutamate, with mean ID(50) values of 11.7 (8.51-16.0) mg/kg and <10 mg/kg, respectively. Its antinociceptive action was significantly reversed by atropine, haloperidol, GABA(A) and GABA(B) antagonists (bicuculline and phaclofen, respectively), but was not affected by L-arginine-nitric oxide, serotonin, adrenergic and the opioid systems. Together, these results indicate that the mechanisms involved in its action are not completely understood, but seem to involve interaction with the cholinergic, dopaminergic, glutamatergic, GABAergic and tachykinergic systems.

Toxicological and phytochemical studies of Aspidosperma subincanum Mart. stem bark (Guatambu).

Aspidosperma subincanum Mart. is widely used in Brazilian folk medicine to treat digestive disorders. In this study, acute and subchronic toxicity and cytotoxicity of stem bark ethanolic extract of Aspidosperma subincanum (EEAs) have been evaluated. In addition, phytochemical analysis was performed. The EEAs had low acute toxicity in mice with LD50 =1129 +/- 154mg/kg p.o. and 397 +/- 15 mg/kg i.p. The LC50 was 1340 +/- 428 microg/mL in the brine shrimp assay. There was no relevance of serious changes in behavioral, hematological and biochemical parameters and no deleterious effect on vital organs of rats that resulted after 30 days daily exposure to 5 and 100 mg/kg of EEAs. Phytochemical analysis of stem bark of A. subincanum revealed the presence of indole alkaloids, saponins, terpenoids, steroids and tannins and resulted in the isolation of oleic acid and guatambuine as major constituents. Using the method of the dose by factor approach, the human safe dose was 210 mg/70 kg/day. The EEAs appears to be safe and non-toxic in low doses in rodents and domestic preparations used by population have relatively security.

Two new 11alpha,12alpha-epoxy-ursan-28,13beta-olides and other triterpenes from Cecropia catharinensis.

Three new triterpenes, 2alpha-acetoxy-3beta,19alpha-dihydroxy-11alpha,12alpha-epoxy-ursan-28,13beta-olide, 3beta-acetoxy-2alpha,19alpha-dihydroxy-11alpha,12alpha-epoxy-ursan-28,13beta-olide and 2-O-acetyl-euscaphic acid together eight known triterpenes were isolated from the roots and stems of Cecropia catharinensis. Their structures were determined by detailed analysis of NMR spectra and the relative configurations established by difference nOe experiments. In addition, four flavonoid glucosides (vitexin, isovitexin, orientin and isoorientin) were found in the leaves.

Antioxidant and anti-inflammatory effects of products from Croton celtidifolius Bailon on carrageenan-induced pleurisy in rats.

Croton celtidifolius Bailon, commonly known as Sangue-de-Adáve or Pau-Andrade, is a tree found in the Atlantic forest of southern Brazil. It has been popularly used for the treatment of inflammatory and ulcerative disorders. Phytochemical analysis demonstrated the presence of flavonoids and proanthocyanidins in an ethyl acetate fraction (EAF) from C. celtidifolius Bailon. In this study, we have evaluated the effects of EAF and its sub-fractions (35 and 63, catechin) on inflammatory (cell migration and plasma extravasation) and oxidative (lipid peroxidation, superoxide dismutase (SOD) activity and superoxide anion production) parameters in carrageenan-induced pleurisy in rats. NO production was also measured by nitrite/nitrate levels. EAF and sub-fraction 63 (63SF) showed anti-inflammatory activity, as indicated by a reduction in plasma extravasation and cell migration (mainly polymorphonuclear leukocytes) to the pleural cavity. Furthermore, EAF treatment decreased the production of superoxide radical anion by cells isolated from the pleural cavity, while it did not affect the nitrite/nitrate levels in exudates. The results show that C. celtidifolius contains substances with antioxidant and anti-inflammatory activity that, at least in part, act by a modulation of oxidative stress by phenolic compounds.

Pharmacological and phytochemical investigations of different parts of Calophyllum brasiliense (Clusiaceae).

Continuing our search for antinociceptive agents from natural sources, this study analyzed the antinociceptive effects of some fractions obtained from different parts (roots, flowers and fruits) of Calophyllum brasiliense, a Brazilian medicinal plant used to treat several diseases, including inflammation and pain. For this purpose, the writhing and formalin induced-pain models in mice were used. We also analyzed the chemical composition of these different parts and tested two pure compounds isolated from chloroform fraction (roots) identified as friedelin (1) and 1,5-dihydroxyxanthone (3), by direct comparison with authentic samples. The results showed that some fractions and both compounds exhibited considerable antinociception properties, particularly against the writhing test, and that these are more potent than acetyl salicylic acid and acetaminophen, two reference drugs used here for comparison.

Dihydrochalcones and coumarins of Esenbeckia grandiflora subsp. brevipetiolata.

Six furoquinolines and five coumarins have been isolated from the roots of Esenbeckia grandiflora subsp. brevipetiolata. The leaves yielded two dihydrochalcones and two flavonol rhamnosides. One of the coumarins (5-senecioyl-xanthotoxin) and the dihydrochalcones are novel compounds and their structures were elucidated by spectroscopic methods. The comparison with the dihydrochalcones previously isolated from another subspecies, E. grandiflora subsp. grandiflora is also provided.

Antifungal activity of sterols and triterpenes isolated from Ganoderma annulare.

Three sterols, 5alpha-ergost-7-en-3beta-ol, 5alpha-ergosta-7,22-dien-3beta-ol and 5,8-epidioxy-5alpha,8alpha-ergosta-6,22-dien-3beta-ol and five triterpenes, applanoxidic acids A, C, F, G and H, have been isolated from Ganoderma annulare. The applanoxidic acids A, C and F were found to inhibit the growth of the fungi Microsporum cannis and Trichophyton mentagrophytes at concentrations of 500 to 1000 microg/ml.

Anti-inflammatory and antioxidant effects of Croton celtidifolius bark.

Croton celtidifolius Baill commonly known as "sangue-de-adave" is a tree found in the Atlantic Forest of south of Brazil, mainly in Santa Catarina. The bark and leaf infusions of this medicinal plant have been popularly used for the treatment of inflammatory diseases. In this study we evaluated the anti-inflammatory and antioxidant properties of crude extract (CE), aqueous fraction (AqF), ethyl acetate fraction (EAF), butanolic fraction (BuF) and catechin, gallocatechin and sub-fractions, 19SF, 35SF and 63SF that contained a mixture of proanthocyanidins and were derived from the EAF fraction. The CE, AqF, EAF, BuF, catechin and sub-fractions 35SF and 63SF reduced paw edema induced by carrageenan. The CE, fractions, sub-fractions and isolated compounds showed antioxidant properties in vitro, all were able to scavenge superoxide anions at a concentration of 100 microg ml(-1). The EAF, catechin and gallocatechin were most effective in the deoxyribose assay, IC50 0.69 (0.44-1.06), 0.20 (0.11-0.39), 0.55 (0.28-1.08) microg x ml(-1) respectively. The CE and other fractions and sub-fractions inhibited deoxyribose degradation up to 1 microg x ml(-1). In the hydrophobic system only AqF did not show lipid peroxidation inhibition. The CE, other fractions, sub-fractions and isolated compounds inhibited lipidid peroxidation only at a concentration of 100 microg x ml(-1). In summary, this study demonstrates that Croton celtidifolius bark has significant anti-inflammatory and antioxidant activity.

Phytochemical analysis and analgesic properties of Curcuma zedoaria grown in Brazil.

The present study describes the phytochemical analysis and analgesic activity of Curcuma zedoaria rhizomes grown in Brazil. The results showed that the hydroalcoholic extract, fractions, specially dichloromethane, and a pure compound, denoted as curcumenol (1), exhibited potent and dose-related analgesic activity when evaluated in several models of pain in mice, including writhing, formalin and capsaicin. Compound (1), which seems to be the main active principle from this plant, presented promising analgesic effects, being several times more potent than different reference drugs evaluated in the same experimental models. The calculated ID50 values (micromol/kg, i.p) were 22 and 12 when evaluated in writhing and capsaicin tests, respectively, and 29 micromol/kg in relation to the second phase of the formalin model. The lack of effect in the hot plate test suggests that (1) act by a mechanism which do not involves the participation of the opioid system. The phytochemical analysis indicated that the chemical composition of the plant grown in Brazil is similar to that grown in other countries. The results confirm and justify the popular use of this plant for the treatment of dolorous processes.

Phytochemical and pharmacological investigations of Virola oleifera leaves.

A methanolic extract and two fractions (n-hexane and ethyl acetate) from Virola oleifera leaves and some compounds (one lignan and two flavonoids) were investigated to verify the analgesic activity by using the writhing test in mice. The crude methanolic extract showed a moderate analgesic effect (about 40% of inhibition in this test at 10 mg/kg), whereas n-hexane and ethyl acetate fractions caused inhibition of 51.3 +/- 5.9% and 50.5 +/- 6.3%, respectively. Oleiferin-C (1), a lignan isolated from the n-hexane fraction, showed an interesting analgesic potential in this model when compared to two standard drugs, paracetamol (4-acetamidophenol) and aspirin (acetylsalicylic acid). The ID50 calculated for this compound was 17.25 micromol/kg, with confidence interval between 13.7 and 21.3 micromol/kg, being about 8 times more potent than the standard drugs. The mixture of two glycoside-flavonoids, identified as astilbin (2) and quercitrin (3), also exhibited good analgesic activity, causing 63% of reduction of abdominal constriction in mice. These results suggest beneficial effect of this plant to treat dolorous processes.

Evaluation of the antinociceptive action caused by ether fraction and a triterpene isolated from resin of Protium kleinii.

This study investigates the antinociception caused by i.p. and p.o. administration of ether fraction and the triterpene identified as urs-12-ene-3beta-16beta-diol, known as Brein, isolated from Protium kleinii in several models of nociception in mice. The systemic administration of ether fraction (0.3 to 10 mg/kg, i.p. or 3 to 60 mg/kg, p.o.) caused a dose-related antinociception when assessed against acetic acid-induced writhing, with mean ID50 values of 1.2 and 16.4 mg/kg, respectively. The ether fraction (5 to 60 mg/kg, i.p. or 30 to 300 mg/kg, p.o.) also produced dose-related inhibition of both phases of formalin induced licking. The mean ID50s values for the early phase were > 60.0 and 62.1 mg/kg, while for the late phase they were 15.4 and 60.0 mg/kg, respectively, given by i.p. and p.o. routes. The ether fraction (3 to 30 mg/kg, i.p. or 10 to 100 mg/kg, p.o.) produced significant inhibition of the neurogenic nociception caused by topical injection of capsaicin, with mean ID50 values of 6.2 and 16.0 mg/kg, respectively. Given orally (1 to 30 mg/kg) the ether fraction produced graded and pronounced inhibition of glutamate-induced hyperalgesia in mice with a mean ID50 value of 15.2 mg/kg. In contrast, the ether fraction failed to produce antinociception when assessed in the thermal model of pain, the tail flick and hot plate tests. The antinociception caused by the ether fraction, in contrast to that of morphine, was not reversed by naloxone when assessed in the formalin-induced licking. The ether fraction did not affect motor coordination or the core body temperature in mices. The triterpene Brein isolated from P. kleinii, given by i.p. route (10 to 100 mg/kg) produced dose-related inhibition of both phases of formalin induced-licking, with mean ID50s values of 15.3 and 20.6 for the early and the late phases, respectively. These data show that the active principle(s) present in the ether fraction from the resin of P. kleinii elicited pronounced antinociception when assessed by i.p. or p.o routes, against both inflammatory and neurogenic nociception. Such effects seem, at least in part, to be related to the presence of the triterpene Brein in the extract. The mechanisms responsible for the antinociceptive action are at this moment not completely understood, but the involvement of the opioid pathway seems unlikely.

Chemical composition and analgesic activity of Calophyllum brasiliense leaves.

This paper describes a phytochemical and pharmacological study with Calophyllum brasiliense leaves, a medicinal plant employed in folk medicine for the treatment of several ailments. Based on spectroscopic evidence, five phenolic compounds were identified as hyperin (hyperoside), amentoflavone, quercetin, gallic acid, and protocatechuic acid. The fractions and some phenolic compounds exhibited significant analgesic activity against the writhing test and in relation to the second phase (inflammatory pain) of the formalin test in mice, suggesting that this plant can be useful for the treatment of dolorous processes.

Triterpenes from the resin of Protium heptaphyllum.

From the neutral fraction of the resin of Protium heptaphyllum, a mixture of alpha- and beta-amyrin, a mixture of maniladiol and brein have been isolated as main components, and the novel 3 beta,24-dihydroxy-urs-12-ene (1), 3-oxo-20S-hydroxytaraxastane (2) and 3 beta,20S-dihydroxytaraxastane (3) as minor components. NMR data of the last three compounds are provided.

3,4-seco-Lupanes and other constituents from Platypodium elegans.

The isolation and NMR data of seco-lupane triterpenes and coumarins from Platypodium elegans are reported.

Ecdysteroids from two Brazilian Vitex species.

A new ecdysteroid, 26-hydroxypinnatasterone (1), together with 20-hydroxyecdysone, was isolated from the stem barks of Vitex cymosa. 20-Hydroxyecdysone, ajugasterone C, ajugasterone C monoacetonide and turkesterone were isolated from the branches of V. polygama. The structure of 1 was determined by spectroscopic methods.

Sorocein I, a new Diels-Alder type adduct from Sorocea ilicifolia.

From ethyl acetate extract of the root bark of Sorocea ilicifolia a new ketalized Diels-Alder type adduct, sorocein I (1), was isolated.

Phytochemical and pharmacological analysis of Bauhinia microstachya (Raddi) Macbr. (Leguminosae).

This paper describes the isolation of four phytoconstituents from the leaves of Bauhinia microstachya, a Brazilian medicinal plant used in folk medicine for the treatment of several ailments. Based on spectroscopic evidence, these compounds were identified as methyl gallate (1), kaempferol 3-O-rhamnosyl (2), quercitrin (3) and myricitrin (4). The crude methanolic extract and two compounds (3 and 4) were tested as analgesic using the writhing test in mice. The extract and compound 3 caused potent and dose-related analgesic effects, confirming the popular use of this plant for the treatment dolorous processes.

I3-naringenin-II8--4'OMe-eriodictyol: a new potential analgesic agent isolated from Rheedia gardneriana leaves.

This paper describes the isolation, identification and analgesic activity of a new biflavonoid from Rheedia gardneriana leaves, which correspond to I3-naringenin-II8-4'-OMe-eriodictyol (GB-2a-II-4'-OMe) (1), with a methoxyl group in position 4 of ring-II. Its structure was determined by spectroscopic data and confirmed by an alkaline hydrolysis. Its analgesic effect was evaluated in a writhing test and a formalin test in mice. It was found that this compound exhibits potent and dose-related analgesic action in both experimental models, with ID50's values of 4.5 micromol/kg against the writhing test and 8.2 and 6.8 micromol/kg against the first and second phase of the formalin test, respectively. It was several times more potent than some well-known analgesic drugs used as reference.

Phytochemical and pharmacognositc investigation of Bauhinia forficata Link (Leguminosae).

We have isolated two phytoconstituents present in the B. forficata leaves, a medicinal plant employed in folk medicine specially for the treatment of diabetes. These compounds were isolated by column chromatography and identified as beta-sitosterol and kaempferol-3,7-dirhamnoside (kaempferitrin) by spectroscopical data and comparison with authentic samples. A comparative study with different parts of the plant indicated that the latter is present only in the leaves, suggesting that it might be useful for a suitable quality control of phytotherapeutics which contain this organ of B. forficata in its composition.