HPLC/MS analysis and anxiolytic-like effect of quercetin and kaempferol flavonoids from Tilia americana var. mexicana

Aim of the study

Around the world, Tilia species have been used in traditional medicine for their properties as tranquilizer. Furthermore, Mexican species of Tilia have been grouped as Tilia americana var. mexicana, but their specific content in flavonoids is poorly described. In this study, inflorescences of Mexican Tilia were collected in three different regions of Mexico to compare their flavonoid content and anxiolytic-like response.

Materials and methods

Flavonoid content was analyzed by using an HPLC–MS technique. For anxiolytic-like response, Tilia inflorescences extracts (from 10 to 300 mg/kg, i.p.) were tested in experimental models (open-field, hole-board and plus-maze tests, as well as sodium pentobarbital-induced hypnosis) in mice.

Results

HPLC–MS analysis revealed specific peaks of flavonoid composition demonstrating some differences in these compounds in flowers and bracts depending on the region of collection. No differences in the neuropharmacological activity among these samples of Tilia were found. Moreover, their effects were associated with quercetin and kaempferol glycosides.

Conclusions

Dissimilarities in the flavonoid composition of Mexican Tilias might imply that these species must be re-classified in more than one species, not as a unique Tilia americana var. mexicana. Since quercetin and kaempferol aglycons demonstrated anxiolytic-like response and that no difference in the pharmacological evaluation was observed between these three Mexican Tilias, we suggest that this pharmacological effect of Tilia inflorescences involves these flavonoids occurrence independently of the kind of glycosides present in the samples reinforcing their use in traditional medicine in several regions of Mexico.     

In vitro activity of Tridax procumbens against promastigotes of Leishmania mexicana

Ethnopharmacological relevance

Tridax procumbens is an active herb against leishmaniasis.

Aim of the study

Leishmaniasis is a group of diseases caused by Leishmania protozoa. We investigated the antileishmanial activity of Tridax procumbens extracts and a pure compound against promastigotes of Leishmania mexicana, the causative agent of cutaneous leishmaniasis in the New World.

Materials and methods

Extracts and (3S)-16,17-didehydrofalcarinol (1) were obtained by chromatographic methods from Tridax procumbens, and the latter identified by spectroscopic analysis. The effect of these extracts and 1 on the growth inhibition of promastigotes of Leishmania mexicana was evaluated. In order to test the safety of extracts and 1, mammalian cells were treated with them, and cell viability was assessed using trypan blue and MTT.

Results

We demonstrated that extracts of Tridax procumbens and 1 showed a pronounced activity against Leishmania mexicana. The methanol extract inhibited promastigotes growth of Leishmania mexicana with a 50% inhibitory concentration (IC₅₀) of 3 μg/ml, while oxylipin 1 exhibited the highest inhibition at IC₅₀ = 0.478 μg/ml.

Conclusions

In this study we report the biological activity of extracts and (3S)-16,17-didehydrofalcarinol (1), obtained from Tridax procumbens, on the promastigote form of Leishmania mexicana, with no effect upon mammalian cells.     

Depressant effects of Clinopodium mexicanum Benth. Govaerts (Lamiaceae) on the central nervous system

Ethnopharmacological relevance

The decoction of leaves of Clinopodium mexicanum Benth. Goaverts (Lamiaceae), commonly known as “Toronjil de Monte”, is used in the Mexican traditional medicine to induce sleep, as well as sedative and analgesic remedy.

Aim of the study

To evaluate the putative depressant effects of an aqueous extract of the medicinal plant Clinopodium mexicanum on the central nervous system (CNS).

Materials and methods

The effects of the extract (AECM) on mice were tested in several animal paradigms, including sodium pentobarbital-induced sleep, open field tests, and hole-board tests. The effects of AECM on pentylenetetrazole- and picrotoxin-induced convulsions in mice and on the antithermonociceptive response in the hot-plate paradigm were also tested. Additionally, the active extract (AECM) was analyzed with HPLC–ESI-MS techniques.

Results

Mice acutely treated with AECM at 100, 200, 500 and 1000 mg/kg doses prolonged the sleeping time induced by sodium pentobarbital (42 mg/kg). This extract, at 100 and 200 mg/kg doses, showed a sedative effect in the hole-board paradigm and decreased spontaneous activity in mice. AECM at 10, 100 and 200 mg/kg prolonged the onset of seizures induced by pentylenetetrazole (90 mg/kg) and antagonized tonic convulsions induced by picrotoxin (10 mg/kg). Additionally, AECM inhibited the response to a thermonociceptive stimulus. The intraperitoneal AECM treatment produced mortality with an LD₅₀ = 2154 mg/kg. Chemical analysis showed that the flavanone glycosides neoponcirin, poncirin, and isonaringenin are the main compounds of the active extract.

Conclusions

This study demonstrates that an acutely administered single dose of an aqueous extract of Clinopodium mexicanum can exert depressant effects on the CNS. These findings are in agreement with the traditional use of Clinopodium mexicanum to induce sleep as well as sedative and analgesic remedy. The chemical analysis of AECM revealed the presence of the flavanone glycosides neoponcirin, poncirin, and isonaringin.     

Anti-nociceptive and anti-inflammatory activities of the Agastache mexicana extracts by using several experimental models in rodents

Ethnopharmacological relevance

Agastache mexicana is a plant that has long been used in large demand in Mexican folk medicine to treat pain, among others affections. Nevertheless, no scientific data confirming its use have been reported. The aim of this investigation was to examine the spectrum of antinociceptive activity of A. mexicana by using different experimental models of nociception in rodents.

Material and methods

Nociceptive activity was induced 30 min post treatment of different doses of hexane, ethyl acetate and methanol extracts from A. mexicana aerial parts. The writhing test in mice, and the formalin and plantar tests as well as the pain-induced functional impairment assay in rats (PIFIR model) were the experimental nociceptive models used. Antinociceptive response of the organic extracts was compared to that observed with the analgesic drug tramadol.

Results

A. mexicana organic extracts produced a dose-dependent and significant inhibition of the abdominal constrictions caused by 1% acetic acid injection (i.p.) in mice. A maximal antinociceptive effectiveness obtained with tramadol was also observed with the administration of hexane and ethyl acetate extracts in comparison to less effectiveness obtained with the methanol extract. At the same range of doses, A. mexicana organic extracts inhibited the behavioral responses in both phases of the formalin pain test, in which a more intense effect was observed in the inflammatory phase than in the neurogenic stage. With regard to the plantar test and PIFIR model, a significant but not dose-dependent antinociceptive response was observed at specific doses that depended on the organic extract evaluated.

Conclusion

The antinociceptive activity of A. mexicana aerial parts depends on the intensity of the painful stimulus induced and involves different kinds of constituents. Our present results reinforce the use of this species in traditional medicine and its utility for pain treatment mainly associated with inflammation.     

Neuropharmacological study of Dracocephalum moldavica L. (Lamiaceae) in mice: sedative effect and chemical analysis of an aqueous extract

Ethnopharmacological relevance

Dracocephalum moldavica is used as a tranquilizer and as remedy for nervous conditions relief in the Mexican traditional medicine. Despite its intensive use no literature reported neuropharmacological studies on Dracocephalum moldavica as yet.

Aim of the study

The sedative, anxiolytic-like and antidepressant-like effects of the aqueous extract of aerial parts of Dracocephalum moldavica (Lamiaceae) (DM) were evaluated in behavioral models in mice. The general toxic effects of DM were evaluated as well as their chemical analysis was performed.

Materials and methods

DM effects were evaluated on pentobarbital-induced sleeping time (SPT), the hole-board (HBT), and the avoidance exploratory behavior (AEBT) tests and on the forced swimming test (FST). General activity and motor coordination were evaluated in the open field (OFT) and Rota-rod tests, respectively. The acute toxicity of DM was determinate by its LD₅₀ dose. The chemical analyses DM were performed by chromatographic and HPLC–ESI-MS techniques.

Results

DM prolonged the pentobarbital-induced sleeping time, induced sedation in the HBT, decreased spontaneous activity and produced motor coordination impairment in mice. However, DM did not show anxiolytic effects in the AEBT or HBT and it was not effective in FST. The DM-treatment produced mortalities with LD₅₀ = 470 mg/kg body weight.The HPLC–ESI-MS analysis of DM revealed that (acacetin, apigenin and luteolin)-7-O-β-d-(6″-O-malonyl)-glucoside derivates are the main compounds of DM.

Conclusions

DM induced sedative actions and a general inhibition of CNS activity observed by the decrease of animals’ general activity, motor coordination and exploration.     

Dose-dependent antihypertensive determination and toxicological studies of tilianin isolated from Agastache mexicana

Ethnopharmacological relevance

Agastache mexicana is used in Mexican traditional medicine for the treatment of hypertension, anxiety and related diseases.

Aim of the study

Current work was developed to establish pharmacological/toxicological parameters of tilianin, a flavone extracted from Agastache mexicana in order to propose it for clinical trials.

Materials and methods

Acute and sub-acute toxicology studies in Imprinting Control Region (ICR) mice and median effective dose (ED₅₀) determination in conscious spontaneously hypertensive rats (SHR) were done.

Results

A median lethal dose (LD₅₀) of 6624 mg/kg (6201, 7076) in mice and significant antihypertensive effect (ED₅₀=53.51 mg/kg) in SHR were determined. Moreover, sub-acute oral administration of tilianin did not alter body weight, clinical chemistry parameters (alanine amino-transferase, aspartate amino-transferase, total cholesterol, high density lipoprotein, low density lipoprotein, triglycerides, glucose and insulin), and also did not induce any toxic or adverse effects on kidney, heart, liver, and lung functions.

Conclusions

We have shown that tilianin, isolated from Agastache mexicana, was not toxic for rodents. Also, its antihypertensive effect was dose-dependent and ED₅₀ (53.51 mg/kg) calculated was lesser than LD₅₀ determined (6624 mg/kg), which suggest a wide range of pharmacology–toxicology patterns. Results support the hypothesis that tilianin must be investigated and developed for clinical trials as antihypertensive drug.     

Comparison of the anti-inflammatory and anti-nociceptive effects of three medicinal plants known as “Snow Lotus” herb in traditional Uighur and Tibetan medicines

Ethnopharmacological relevance

Saussurea involucrata (Kar. et Kir.) Sch.-Bip. (Compositae) has long been used under the herbal name “Snow Lotus” for the treatment of rheumatoid arthritis, stomachache and dysmenorrhea in Uighur folk medicine. In traditional Tibetan medicine, Saussurea laniceps Hand.-Mazz. and Saussurea medusa Maxim. have also been used under the name “Snow Lotus” and prescribed for the treatment of pain and inflammatory conditions.

Aim of the study

The present study evaluated the pharmacological effects of three species of “Snow Lotus” in experimental inflammation and pain models, and determined the chemical compounds that may correlate with their pharmacological activities.

Materials and methods

The anti-inflammatory activities of the three herbs were observed by using carrageenan-induced paw edema in rats and xylene-induced ear edema in mice. Investigations on the analgesic effects were conducted, including acetic acid-induced writhing and hot-plate test. An UPLC–MS method was developed to analyze the chemical composition of the three herbs and of plasma samples after herb administration.

Results

In rat paw edema model, the peak inhibitory effects of Saussurea laniceps and Saussurea involucrata (55.1% and 42.2%, respectively) were recorded with the dose of 400 mg/kg at 3 h post-carrageenan injection. In mouse ear edema model, oral administration of Saussurea laniceps, Saussurea involucrata and Saussurea medusa extract (400 mg/kg) resulted in a significant inhibition of ear edema by 40.9%, 33.3%, and 9.1%, respectively. In the writhing test, oral administration of Saussurea laniceps extract (100, 200 and 400 mg/kg) resulted in a significant inhibition of writhings by 13.5%, 22.3%, and 43.5%, respectively. In the hot-plate test, Saussurea laniceps extract significantly increased the latency of jumping response by 38.2% and 52.7% when treated orally at 200 and 400 mg/kg in mice, respectively. Flavonoids, coumarins and lignins were found to be present in plasma after administration of the extracts and may be the basis of the observed pharmacological effects.

Conclusion

The results clearly demonstrated that Saussurea laniceps was most effective; Saussurea involucrata exhibited a moderate potency, whereas Saussurea medusa possessed little effect against the experimental edema and pains. This study also supported discrimination among the three herbs when using them in folk medicine.     

Chemical composition and cellular toxicity of ethnobotanical-based hot and cold aqueous preparations of the tiger′s milk mushroom (Lignosus rhinocerotis)

Ethnopharmacological relevance

The sclerotium of the “tiger′s milk mushroom” (Lignosus rhinocerotis) is used as tonic and folk medicine for the treatment of cancer, fever, cough and asthma by the local and indigenous communities. It is traditionally prepared by either boiling or maceration-like methods; however, there is no attempt to understand how different processing methods might affect their efficacies as anticancer agents.

Aim of the study

This investigation was undertaken to evaluate the cytotoxicity of the hot and cold aqueous extracts of Lignosus rhinocerotis and to deduce the nature of the chemical component(s) that might be responsible for differential cellular toxicity of the extracts.

Materials and methods

The hot (LR-HA) and cold (LR-CA) aqueous extracts of the sclerotium of Lignosus rhinocerotis were prepared. The levels of bioactive components in the extracts were determined and chemical profiling was performed using UPLC-ESI-MS, SDS-PAGE and SELDI-TOF MS. Cytotoxicity of LR-HA and LR-CA against a panel of human cancer and normal cell lines was assessed by the MTT and trypan blue exclusion assays. Changes in cell morphology upon treatment with the extracts were observed. The chemical composition and bioactivities data were correlated to explain the nature of the cytotoxic component(s).

Results

LR-HA and LR-CA were particularly abundant in polar components. Both extracts exhibited varying degree of cytotoxicity against the cancer cell lines with LR-CA showed significantly stronger cytotoxicity (IC₅₀: 37–355 µg/ml) than LR-HA (IC₅₀>500 µg/ml); however, LR-CA lacked selectivity in that it also has cytotoxic effect on the normal cell lines. Based on the results of protein profiling of heat-treated LR-CA (40–100 °C) coupled to the MTT assay, the cytotoxic component(s) in LR-CA were deduced to be thermo-labile, water-soluble protein/peptide(s).

Conclusion

Our findings have shown that the use of different preparation methods (hot and cold aqueous extraction) for Lignosus rhinocerotis has resulted in extracts with distinctively different cellular toxicity in which the cytotoxic constituents were present only in LR-CA.     

Screening of the topical anti-inflammatory activity of the bark of Acacia cornigera Willdenow, Byrsonima crassifolia Kunth, Sweetia panamensis Yakovlev and the leaves of Sphagneticola trilobata Hitchcock

Ethnopharmacological relevance

An investigation of topical anti-inflammatory activity was undertaken on plants used in Central America traditional medicine.

Aim of study

Four herbal drugs used in the folk medicine of Central America to treat inflammatory skin affections (Acacia cornigera bark, Byrsonima crassifolia bark, Sphagneticola trilobata leaves and Sweetia panamensis bark) were evaluated for their topical anti-inflammatory activity.

Materials and methods

Petroleum ether, chloroform and methanol extracts were obtained for herbal medicines and then extracts were tested on Croton oil-induced ear dermatitis model in mice.

Results

Almost all the extracts reduced the Croton oil-induced ear dermatitis in mice and the chloroform ones showed the highest activity, with ID₅₀ (dose giving 50% oedema inhibition) values ranging from 112 μg/cm² (Byrsonima crassifolia) to 183 μg/cm² (Sphagneticola trilobata). As reference, ID₅₀ of the non-steroidal anti-inflammatory drug indomethacin was 93 μg/cm².

Conclusions

Lipophilic extracts from these species can be regarded as potential sources of anti-inflammatory principles.     

Novel bisabolane derivative from “arnica-da-serra” (Vernonieae: Asteraceae) reduces pro-nociceptive cytokines levels in LPS-stimulated rat macrophages

Ethnopharmacology relevance

Hydro alcoholic leaves extracts (HALE) of Lychnophora ericoides Mart. (“false arnica” or “arnica-da-serra”) had been popularly used against pain and inflammatory process.

Aim

The present work aimed to look for possible active volatile compounds that could be found in HALE of Lychnophora ericoides among the non volatile anti-inflammatory and analgesic compounds previously reported.

Methods

Harvests were performed during the end of the wet summer season (April) when scented branches were instantly collected and frozen. HALE's were simulated at the lab by following the procedures lectured by the locals. Mass Spectrometry experiments suggested structural information when using both EI–MS and ESI–MS/MS. After isolation through classical thin layer chromatography (TLC) procedures, the NMR experiments and signals assignments were carried out. The effects on the cytokines or nitric oxide (NO) production were assessed at in vitro assays that had monitored the levels of these substances on the supernatant of LPS-stimulated macrophage primary cell culture.

Results

The major metabolite from HALE was isolated from the essential oil and the major compound had its molecular formulae established by Mass Spectrometry (High Resolution) and its structure by NMR. Literature-based investigation enables us to define the structure of the new metabolite as 6-methyl-2-(4-methylcyclohex-4-enyl-2-acetyloxy) hept-5-en-2-ol and its name as orto-acetoxy-bisabolol. In vitro assay of interleukins release inhibition was carried out using rat peritoneal macrophages cultures. IL-1β and TNF-α levels were significantly reduced when cells were previously treated with low doses of orto-acetoxy-bisabolol, but neither IL-6 nor NO levels have their levels reduced. Results suggest that ethnical knowledge of anti-inflammatory and analgesic effects of the “arnica-da-serra” HALE may be associated to the orto-acetoxy-bisabolol ability on synthesis inhibition of the key inflammatory/hypernociceptive mediators.

Conclusions

Phytochemical investigation of the volatile active compounds in Lychnophora ericoides HALE allows us to isolate a new bisabolane derivative (orto-acetoxy-bisabolol) and to infer that this compound inhibits the synthesis of TNF-α and IL-1β, two important inflammatory mediators in the hypernociception. Our present data, in addition to literature's data, furnish scientific support to folk's use of Lychnophora ericoides as an endemic wound healer.     

Antipyretic and anti-inflammatory properties of the ethanolic extract,dichloromethane fraction and costunolide from Magnolia ovata (Magnoliaceae)

Aim of the study

Magnolia ovata (A.St.-Hil.) Spreng (formerly Talauma ovata), known as “pinha-do-brejo” or “baguaçu”, is a large tree widely distributed in Brazil. Its trunk bark has been used in folk medicine against fever. However, no data have been published to support the antipyretic ethnopharmacological use. This study investigated the antipyretic and anti-inflammatory effects of the ethanolic extract (EEMO), dichloromethane fraction (DCM), and the isolated compound costunolide.

Materials and methods

The antipyretic and anti-inflammatory activities were evaluated in experimental models of fever and inflammation in mice.

Results

The oral administration of EEMO, DCM and costunolide inhibited carrageenan (Cg)-induced paw oedema (ID₅₀ 72.35 (38.64–135.46) mg/kg, 5.8 (2.41–14.04) mg/kg and 0.18 (0.12–0.27) mg/kg, respectively) and was effective in abolishing lipopolysaccharide (LPS)-induced fever (30 mg/kg, 4.5 mg/kg and 0.15 mg/kg, respectively). EEMO was also effective in reducing cell migration in the pleurisy model. Intraplantar injection of costunolide also reduced the paw oedema, myeloperoxidase and N-acetyl-glucosaminidase activity induced by Cg in mice.

Conclusions

Collectively, these results show, for the first time, that extracts obtained from Magnolia ovata possess antipyretic and anti-inflammatory properties, and costunolide appears to be the compound responsible for these effects.     

Zataria multiflora Boiss. (Shirazi thyme)—An ancient condiment with modern pharmaceutical uses

Ethnopharmacological relevance

Zataria multiflora Boiss. (ZM) is a thyme-like plant belonging to the Lamiaceae family that grows wild only in Iran, Pakistan and Afghanistan. This plant with the vernacular name of Avishan-e-Shirazi (Shirazi thyme) in Iran is a valuable medicinal and condimental plant. It has several traditional uses as an antiseptic, carminative, stimulant, diaphoretic, diuretic, anesthetic, anti-spasmodic and analgesic.

Aim of the study

This paper reviews the ethnopharmacology, pharmacology, toxicology, modern pharmaceutical uses and phytochemistry of Zataria multiflora, and highlights the gaps in our knowledge deserving further research.

Materials and methods

All relevant databases were searched for the terms “Zataria”, “Zataria multiflora”, “Shirazi thyme” and “Iranian thyme” without limitation up to 24th October 2012. Information on Zataria multiflora was collected via electronic search using Pubmed, Scopus, Web of Science and SID (for articles in Persian language), and local books on ethnopharmacology.

Results

ZM has played an important role in Iranian traditional medicine. In light of the modern pharmacological and clinical investigations, ZM is a valuable medicinal and condimental plant that has anti-microbial, antioxidative, anti-inflammatory, spasmolytic and anti-nociceptive properties. The oil of ZM contains high percentages of oxygenated monoterpenes, in particular thymol and carvacrol, and exhibits excellent anti-microbial properties.

Conclusions

Overall, antimicrobial property appears to be the most interesting studied biological effect of ZM. The lack of a comprehensive phytochemical analysis of ZM is an important limitation that can be noted regarding most of the previous studies.     

Involvement of glutamate and cytokine pathways on antinociceptive effect of Pfaffia glomerata in mice

Ethnopharmacological relevance

Pfaffia glomerata (Spreng) Pedersen (Amaranthaceae) is a medicinal plant known in Brazil as “Paratudo” and “Brazilian ginseng” and is commonly used as tonic, antidiabetic and to treat gastric disorders.

Aim of the study

This study evaluates the possible mechanism by which hydroalcoholic extract (HE) of Pfaffia glomerata exerts its antinociceptive effect.

Materials and methods

The HE was evaluated in acetic acid and glutamate models of pain or by biting behavior following intrathecal (i.t.) administration of agonists of excitatory aminoacids (EAA) receptors glutamate and pro-inflammatory cytokines, IL-1β and TNF-α in mice.

Results

Oral administration of HE produced dose-dependent inhibition of acetic acid-induced visceral pain and glutamate-induced pain, with ID₅₀ of 64.6 (47.7–87.5) mg/kg and ID₅₀ of 370.8 (253.4–542.7) mg/kg, respectively. The HE (300 mg/kg, p.o.) antinociception, in the acetic acid test, was not affected by i.p. treatment of animals with naloxone. In addition, HE (300 mg/kg, p.o.) inhibited the pain-related behaviors induced by i.t. injection of trans-ACPD and TNF-α, but not by NMDA, AMPA, kainate or IL-1β.

Conclusions

Our results suggest that inhibition of glutamatergic metabotropic receptors and TNF-α may account for the antinociceptive action reported for the HE in models of chemical pain used in this study.     

Characterization of the antinociceptive and anti-inflammatory activities from Cocos nucifera L. (Palmae)

Aim of the study

Cocos nucifera cultivated in Brazil is known as “coco-da-Bahia” or “coqueiro-da-Índia”. The tea from the husk fiber is widely used to several inflammatory disorders. Crude extract and fractions obtained from Cocos nucifera “common variety” were evaluated to test the anti-inflammatory and antinociceptive activities.

Materials and methods

Crude extract (CE, 50, 100, and 150 mg/kg), fraction 1 (F1, molecular weight lesser than 1 kDa, 1, 10, and 50 mg/kg), fraction 2 (F2, molecular weight higher than 1 kDa, 1, 10, and 50 mg/kg), and the references drugs morphine (5 mg/kg), acetilsalicilic acid (200 mg/kg), prometazine (30 mg/kg), and metisergide (5 mg/kg) were evaluated on models of analgesia and inflammation.

Results

CE, F1, and F2 significantly develop peripheral and central antinociceptive activity but with less effect on supra-spinal regions of the brain. Administration of the opioid antagonist, naloxone (5 mg/kg) inhibited the antinociceptive effect indicating that Cocos nucifera crude extract and fractions may be acting in opioid receptors. CE and F1 also inhibited rat paw edema induced by histamine, and serotonin.

Conclusions

results demonstrated that Cocos nucifera and its fractions have antinociceptive and anti-inflammatory activities which confirm the popular use of this plant in several inflammatory disorders.     

Antiplasmodial activity of extracts from seven medicinal plants used in malaria treatment in Cameroon

Aim of the study

In a search for new plant-derived biologically active compounds against malaria parasites, we have carried out an ethnopharmacological study to evaluate the susceptibility of cultured Plasmodium falciparum to extracts and fractions from seven Cameroonian medicinal plants used in malaria treatment. We have also explored the inhibition of the Plasmodium falciparum cysteine protease Falcipain-2.

Materials and methods

Plant materials were extracted by maceration in organic solvents, and subsequently partitioned or fractionated to afford test fractions. The susceptibility of erythrocytes and the W2 strain of Plasmodium falciparum to plant extracts was evaluated in culture. In addition, the ability of annonaceous extracts to inhibit recombinant cysteine protease Falcipain-2 was also assessed.

Results and discussion

The extracts showed no toxicity against erythrocytes. The majority of plant extracts were highly active against Plasmodium falciparumin vitro, with IC₅₀ values lower than 5 μg/ml. Annonaceous extracts (acetogenin-rich fractions and interface precipitates) exhibited the highest potency. Some of these extracts exhibited modest inhibition of Falcipain-2.

Conclusion

These results support continued investigation of components of traditional medicines as potential new antimalarial agents.     

The antinociceptive and anti-inflammatory activities of Piptadenia stipulacea Benth. (Fabaceae)

Aim

In this study, we attempted to identify the possible antinociceptive and anti-inflammatory actions of the aqueous phase, the ethyl acetate phase and one unknown flavonoid obtained from aerial parts of Piptadenia stipulacea, known in Brazil as “jurema-branca”, “carcará” and “rasga-beiço”.

Materials and methods

Aerial parts of Piptadenia stipulacea were used and after fractionation, the flavonoid FGAL was obtained. Experiments were conducted on Swiss mice using the acetic acid-induced writhing test, the hot plate test, the formalin-induced pain test and zymosan A-induced peritonitis test.

Results

The aqueous and ethyl acetate phases (p.o., 100 mg/kg); and the flavonoid FGAL (p.o. and i.p. at 100 μmol/kg), reduced the nociception produced by acetic acid, by 49.92%, 54.62%, 38.97% and 64.79%, respectively. In vivo inhibition of nociception by the ethyl acetate phase (100 mg/kg, p.o.) in the hot plate test was favorable, indicating that this fraction exhibited central activity. The ethyl acetate phase (100 mg/kg, p.o.) reduced the formalin effects in both phases by 28.51% and 55.72%, respectively. Treatment with the aqueous phase (100 mg/kg, p.o.) and FGAL (100 μmol/kg, i.p.) only protected the second phase by 69.76% and 68.78%, respectively. In addition, it was observed in the zymosan A-induced peritonitis test that the aqueous phase, the ethyl acetate phase and the FGAL exhibited anti-inflammatory activity, reducing significantly the number of recruit cells by 35.84%, 37.70% and FGAL (1), respectively.

Conclusions

These data demonstrate that the FGAL elicits pronounced antinociceptive activity against several pain models. The actions of this flavonoid probably are due to antioxidative properties. However, pharmacological and chemical studies are continuing in order to characterize the mechanism(s) responsible for this antinociceptive action and also to identify other active substances present in Piptadenia stipulacea.     

Anxiolytic-like effect of Sonchus oleraceus L. in mice

Ethnopharmacological relevance

Sonchus oleraceus L. has been used as a general tonic in Brazilian folk medicine. Nevertheless, available scientific information regarding this species is scarce; there are no reports related to its possible effect on the central nervous system.

Aim of the study

This study was conducted to establish the anxiolytic effect of extracts from the aerial parts of Sonchus oleraceus.

Materials and methods

This study evaluated the effect of hydroethanolic and dichloromethane extracts of Sonchus oleraceus in mice submitted to the elevated plus-maze and open-field tests. Clonazepam was used as the standard drug.

Results

In the elevated plus-maze test, the Sonchus oleraceus extracts increased the percentage of open arm entries (P < 0.05) and time spent in the open-arm portions of the maze (P < 0.05). The extracts induce an anti-thigmotactic effect, evidenced by increased locomotor activity into the central part of the open field set-up (P < 0.05). The extracts administered at 30–300 mg/kg, p.o. had a similar anxiolytic effect to clonazepam (0.5 mg/kg, p.o.).

Conclusion

These data indicate that Sonchus oleraceus extract exerts an anxiolytic-like effect on mice.     

An herbal decoction of Radix astragali and Radix angelicae sinensis promotes hematopoiesis and thrombopoiesis

Ethnopharmacological relevance

A decoction containing Radix angelicae sinensis and Radix astragali (Danggui Buxue Tang, DBT) has been used to raise the “Qi” and nourish the “Blood”. However, its effects on haematopoiesis and particularly thrombopoiesis have not been studied.

Aims

This study aims to examine the effects of DBT on hematopoiesis and thrombopoiesis.

Materials and methods

A myelosuppression mouse model was treated with DBT (10 mg/kg/day). Peripheral blood cells from DBT and thrombopoietin-treated samples were counted on days 0, 7, 14 and 21. Then CFU assays were used to determine the effects of DBT on the megakaryocytic progenitor cells and other lineages. Last, analyses of annexin V, caspase-3, and mitochondrial membrane potential were conducted in megakaryocytic cell line M-07e.

Results

Morphological examination showed that DBT treatment significantly increased the recovery of the megakaryocytic series. DBT significantly enhanced the platelet recovery and CFU-MK formation in vivo. DBT significantly promoted CFU-MK and CFU-F formation. Last, we observed the antiapoptotic effects of DBT on M-07e cells.

Conclusion

DBT might promote haematopoiesis and thrombopoiesis in the mouse model through (i) directly promoting the growth of megakaryocytes; (ii) indirectly promoting the growth of bone marrow stromal cells; (iii) inhibiting apoptosis of megakaryocytes.