Anti-inflammatory and antinociceptive activities of the ethanolic extract of Bougainvillea xbuttiana

Ethnopharmacological relevance

Bougainvillea xbuttiana is widely distributed in Mexico and it is used as an analgesic in folk medicine.

Aim of the study

In the present study the in vivo antinociceptive and anti-inflammatory effects of the Bougainvillea xbuttiana ethanolic extract have been studied in mice.

Materials and methods

The phytochemical analysis was performed. Antinociceptive activity was evaluated through writhing and formalin test in mice. The anti-inflammatory activity was determined with the carrageenan-induced mice paw oedema model. IL-6, IL-10 and IFN-γ levels were determined by enzyme-like immunosorbent assay, whereas TNF and nitrite levels were detected by standard assay with L929 cells and colorimetric Griess reactive, respectively.

Results

The results showed that the ethanolic extract of the Bougainvillea xbuttiana has significant anti-inflammatory and antinociceptive activities, by inhibition of nociception induced by acetic acid and paw oedema. This extract also induced a decrease in TNF levels and an increase of IL-6, IFN-γ and NO levels that we observed up to 2 h. The highest levels of IL-10 were observed up to 4 h. The ratios of pro-/anti-inflammatory cytokines in sera from mice injected with the ethanolic extract, may be manifesting an anti-inflammatory status.

Conclusions

The present study provides convincing evidences that Bougainvillea xbuttiana extract possesses significant anti-nociceptive and anti-inflammatory effects.     

Hypoglycemic effects of Cecropia pachystachya in normal and alloxan-induced diabetic rats

Ethnopharmacological relevance

Leaves of Cecropia pachystachya are described in the folk medicine as possessing antitusive, expectorant, antiasthmatic and hypoglycemic effects.

Aim of the study

To investigate the hypoglycemic and antioxidant effects of methanolic extract from the leaves of Cecropia pachystachya. The total amount of phenolic and flavonoids compounds was determined and the qualitative composition of the extract was analyzed.

Materials and methods

The hypoglycemic effect of the extract was tested in normal, glucose loading and alloxan-induced diabetic rats. The antioxidant activity was assessed by DPPH free radical scavenging and reduction power assays. The total amount of phenolic and flavonoids compounds was determined by Folin-Denis and AlCl₃ reagent method, respectively. The qualitative composition of the extract was analyzed using a HPLC-DAD system.

Results

The glucose tolerance test showed that in diabetic rats, the extract caused a significant hypoglycemic effect with a blood glucose reduction of 68% after 12 h. The administration of the extract in alloxan-induced diabetic rats also produced a significant reduction in the blood glucose levels at all points being more pronounced at 90 min (reduction of 60%). After 120 min, no significant difference was observed between the blood levels of the rats treated with the extract and those treated with the standard drugs (metformin and glibenclamide). The extract also presented relevant antioxidant activity with IC₅₀ = 3.1 μg/ml (DPPH assay) and EC₅₀ = 10.8 μg/ml (reduction power). Results were compared with the reference antioxidants quercetin, rutin, and ascorbic acid. The content of flavonoids was 83 mg/g plant and that of phenolics was 326 mg/g plant. Chlorogenic acid and the C-glycosylated flavones, orientin and isoorientin, were identified in the extract.

Conclusions

In conclusion, the findings showed that the folk medicinal plant Cecropia pachystachya possesses hypoglycemic and antioxidant effects which confirmed the traditional use of the plant in the treatment of diabetes. Chlorogenic acid and the C-glycosylated flavonoids may explain these activities.     

Analgesic and antimalarial activities of crude leaf extract and fractions of Acalypha wilkensiana

Aim of the study

Antiplasmodial and analgesic activities of leaf extract and fractions of Acalypha wilkensiana were evaluated to ascertain the folkloric claim of its antimalarial and analgesic activities.

Materials and methods

The crude leaf extract (220–659 mg/kg) and fractions (chloroform and aqueous; 440 mg/kg) of Acalypha wilkensiana were investigated for antiplasmodial activity against chloroquine sensitive Plasmodium berghei infections in mice and for analgesic activity against chemical and heat-induced pains. The antiplasmodial activity during early and established infections as well as prophylactic activity were investigated. Chloroquine (5 mg/kg) and pyrimethamine (1.2 mg/kg) were used as positive controls. Thin films made from tail blood of each mouse were used to assess the level of parasitaemia of the mice. Analgesic activity of the crude extract was also evaluated against acetic acid, formalin and heat-induced pains.

Results

The extract and its fractions dose-dependently reduced parasitaemia induced by chloroquine sensitive Plasmodium berghei infection in prophylactic, suppressive and curative models in mice. These reductions were statistically significant (p < 0.001). They also improved the mean survival time (MST) from 16 to 22 days relative to control (p < 0.01–0.001). The activities of extract/fractions were incomparable to that of the standard drugs used (chloroquine and pyrimethamine). On chemically and thermally induced pains, the extract inhibited acetic acid and formalin-induced inflammation as well as hot plate-induced pain in mice. These inhibitions were statistically significant (p < 0.001) and in a dose-dependent fashion.

Conclusion

The antiparasitaemic and analgesic effects may in part be mediated through the chemical constituents of the plant.     

Studies on the analgesic,anti-inflammatory and antipyretic effects of Parquetina nigrescens leaf extract

Ethnopharmacological relevance

Parquetina nigrescens is a shrub that is commonly used in different parts of West Africa for the treatment of several ailments which includes pain, fever and inflammatory conditions.

Aim of the study

The present study was designed to investigate the analgesic, anti-inflammatory and antipyretic effects of the aqueous extract of Parquetina nigrescens leaves in rats.

Materials and methods

Five groups were used for each study, groups 1 and 5 served as control (saline) and reference (indomethacine) respectively, while groups 2–4 received the extract (50–200 mg/kg) orally. Formalin paw licking and hot plate latency tests were used for analgesic studies. Carrageenan oedema, cotton pellet granuloma and formaldehyde arthritis models were used to quantify the anti-inflammatory activities while the brewer’s yeast was used for inducing pyrexia.

Results

The results of the analgesic study show that the extract produced significant (p < 0.05) analgesia in the hot plate and in the formalin tests. In the anti-inflammatory study, Parquetina nigrescens produced significant (p < 0.05) inhibition of the various types of inflammation. The extract also inhibited the pyrexia induced by brewer’s yeast.

Conclusion

The result justifies the traditional uses of Parquetina nigrescens for the treatment of fever, inflammatory and painful conditions.     

Anti-inflammatory and analgesic activities of methanolic extract of Kigelia pinnata DC flower

Ethnopharmacological relevance

Kigelia pinnata DC is extensively used in Indian traditional medicine for several diseases including inflammatory and painful disorders.

Aim of the study

The aim of the present study is to investigate the possible anti-inflammatory and analgesic activities of methanolic extract of Kigelia pinnata flower (MKFL) to support the medicinal uses claimed by folklore practitioners.

Materials and methods

MKFL is evaluated for its anti-inflammatory activity in carrageenan-induced paw edema model in rats and analgesic activity in acetic acid-induced writhing, hot plate and formalin-induced paw licking models in mice.

Results

MKFL exhibited a significant (P < 0.01) anti-inflammatory and analgesic activities with the doses of 100, 200 and 400 mg/kg b.w. in rats and mice respectively.

Conclusions

The results of the experimental study thus strongly support the traditional use of this plant for inflammatory and pain disorders.     

Anticonvulsant activity of Benkara malabarica (Linn.) root extract: In vitro and in vivo investigation

Aim of the study

To systematically investigate the anticonvulsant activity of methanol extract of Benkara malabarica roots and to provide a biochemical basis elucidating its mode of action.

Methods

The median lethal dose (LD₅₀) of Benkara malabarica extract was determined. The anticonvulsant activity of the extract was assessed in strychnine-induced and isoniazide-induced convulsion models; phenytoin (20 mg/kg) and diazepam (1 mg/kg) were used as standards, respectively. Percentage protection provided by the drug was accounted as decrease in the number of convulsions within 8 h of observation. Mechanism of action was studied by performing GABA transaminase (GABA-T) assay, isolated from rat brain. Active constituent was isolated and characterized from the plant extract.

Results

The median lethal dose (LD50) of Benkara malabarica was found to be more than 500 mg/kg. It demonstrated 30% and 35% protection against strychnine-induced convulsions and 60% and 80% protection against isoniazide-induced convulsions, at doses of 25 mg/kg and 50 mg/kg, respectively. Enzyme assay results revealed that Benkara malabarica extract possesses GABA-T inhibitory activity (IC50 = 0.721 mg/ml). Scopoletin which was identified as the major constituent of the extract was found to be an inhibitor of GABA-T (IC50 = 10.57 μM).

Conclusions

The anticonvulsant activity of the plant extract is predominantly GABA mediated and may be due to the action of scopoletin alone or is a result of synergy of different compounds in the extract in which scopoletin is the major constituent.     

Qualea parviflora Mart.: An integrative study to validate the gastroprotective,antidiarrheal, antihemorragic and mutagenic action

Ethnopharmacological relevance

Qualea parviflora Mart. is a medicinal species commonly found in the Brazilian Cerrado biome.

Aim of the study

Based on ethnopharmacological data, methanolic extract from Qualea parviflora (QP) bark was evaluated for its antiulcer, analgesic, anti-hemorrhagic, mutagenic and anti-Helicobacter pylori activities.

Material and methods

The gastroprotective action of the extract was evaluated in rodent experimental models (HCl/ethanol, ethanol or NSAID). We also evaluated mutagenic effect (Ames assay), anti-Helicobacter pylori, anti-hemorrhagic action, analgesic and inflammatory effects (hot-plate test and carrageenin-induced hind paw edema) of methanolic extract from Qualea parviflora.

Results

QP (500 mg/kg, p.o.) was able to protect gastric mucosa against HCl/ethanol solution (77%), absolute ethanol (97%), and also against injurious effect of NSAID (36%). When QP was challenged with sulfhydryl depletor compound, the gastroprotective action of extract was abolished. QP treatment was able to maintain the GSH level and show a concentration-dependent inhibition effect on the lipid peroxidation. QP present anti-Helicobacter pylori effect (MIC = 75 μg/mL), anti-hemorrhagic and antidiarrheal action but not present analgesic or anti-inflammatory effect.

Conclusion

methanolic extract from Qualea parviflora had gastroprotective effect related to the increase of gastric mucosa defensive factors such PGE₂ levels and maintain the basal gastric glutathione levels. The methanolic extract also showed anti-Helicobacter pylori activity, anti-hemorrhagic effect and antioxidant action, but absence of analgesic, mutagenic and toxic effects, a profile that adds safety to its use.     

In vivo antimalarial activities of Enantia polycarpa stem bark against Plasmodium berghei berghei in mice

Ethnopharmacological relevance

Enantia polycarpa (PC) Engl. Et Diels (Annonaceae) is used in traditional medicine as an antimalarial remedy in Southern Nigeria.

Aim of the study

The antimalarial activities of ethanolic stem bark extracts of Enantia polycarpa was studied in vivo, in mice infected with Plasmodium berghei berghei.

Materials and methods

The ethanolic stem bark extract of Enantia polycarpa was administered at doses ranging from 200 to 600 mg/kg/day to Plasmodium berghei infected mice in both early and established models of antiplasmodial studies.

Results

The extract of Enantia polycarpa exhibited promising antimalarial activity against both early and established infections. At a dose of 600 mg/kg the extract achieved a 75.8% and 72% chemosuppression of parasitaemia in the study of acute and established infections, respectively. The extract also prolonged mean survival time of Plasmodium berghei infected mice during the study of established infection. The mean survival time of mice administered Enantia polycarpa extract at 600 mg/kg/day (27 days) was significantly longer than infected/untreated control (12 days). For the acute toxicity study the extract had an intraperitoneal LD₅₀ of 186 mg/kg but caused no mortality when administered orally at doses as high as 2,000 and 4,000 mg/kg.

Conclusions

Collectively, the results indicate that Enantia polycarpa is safe when administered orally and possesses promising antimalarial activity, thus supporting its use in traditional medicine for the treatment of malaria.     

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.     

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.     

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.     

Antimalarial compounds from the aerial parts of Flacourtia indica (Flacourtiaceae)

Aim of the study

In the Comoros Islands, the aerial parts of Flacourtia indica are used in traditional medicine to treat malaria. Because of the important use of this plant, the phytochemistry of the aerial parts was investigated.

Materials and methods

Three compounds were isolated from the decoction of this plant material, Pyrocatechol, Homaloside D and Poliothrysoside. The in vitro antiplasmodial activity on the chloroquine-resistant strain (W2) of Plasmodium falciparum and the cytotoxicity on two complementary human cell lines (THP1, HepG2), of AcOEt extract obtained after liquid/liquid extraction of the decoction and pure compounds, were evaluated.

Results

The Poliothrysoside isolated from the AcOEt extract presented a strong antiplasmodial activity (IC₅₀ = 7.4 μM) and a good selectivity index (>28) similar to chloroquine.

Conclusion

This study reports for the first time antiplasmodial activity for Flacourtia indica, for its AcOEt extract and the three major constituents and confirms its traditional use.     

Anthelmintic activity of Ziziphus nummularia (bark) and Acacia nilotica (fruit) against Trichostrongylid nematodes of sheep

Ethnopharmacological relevance

Ziziphus nummularia (Rhamnaceae) and Acacia nilotica (Fabaceae) are being used as anthelmintics in ethnoveterinary medicinal system of Pakistan.

Aim of the study

Present study was conducted to determine the anthelmintic activity of Ziziphus nummularia (bark) and Acacia nilotica (fruit) in order to justify their traditional use in veterinary medicine.

Materials and methods

In vitro anthelmintic activity of crude methanolic extract (CME) of both the plants was determined against Haemonchus contortus by the adult motility assay, the egg hatch test and the larval development assay. In vivo anthelmintic activity was evaluated in sheep naturally infected with gastrointestinal nematodes by administering increasing doses of crude powder (CP) and CME (1.0–3.0 g/kg).

Results

Both the plants exhibited dose- and time-dependent anthelmintic effects by causing mortality of worms, and inhibiting egg hatching and larval development. Acacia nilotica (LC₅₀ = 512.86 and 194.98 μg/ml) was found to be more potent than Ziziphus nummularia (LC₅₀ = 676.08 and 398.11 μg/ml) in egg hatch test and larval development assay, respectively. In vivo, maximum fecal egg count reduction (84.7%) was recorded on day 13 post-treatment in sheep treated with Ziziphus nummularia CME (3.0 g/kg) followed by 78.5% on same day with Acacia nilotica CME (3.0 g/kg).

Conclusions

These data show that both Ziziphus nummularia and Acacia nilotica possess anthelmintic activity in vitro and in vivo, justifying their use in traditional veterinary medicine in Pakistan.     

Estimation of anti-inflammatory,antinociceptive and antioxidant activities on Arctium minus (Hill) Bernh. ssp. minus

Ethnopharmacological relevance

Arctium minus (Hill) Bernh. ssp. minus (Asteraceae) leaves are used to alleviate rheumatic pain, against fever and sunstroke with externally application in Turkish folk medicine.

Aim of the study

To evaluate the anti-inflammatory, antinociceptive and antioxidant activities of aqueous and ethanol extracts prepared from the leaves of Arctium minus ssp. minus.

Materials and methods

The ethanolic and aqueous extracts from the leaves of Arctium minus ssp. minus were evaluated in mice for anti-inflammatory activity using carrageenan-induced hind paw edema model and for antinociceptive activity using p-benzoquinone-induced abdominal contractions test. Moreover, the antioxidant power of the extracts has been determined by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and flow injection analysis-luminol chemiluminescence (FIA-CL). In addition, the total phenolic content in both extracts was determined with spectrophotometric method.

Results

Our results showed that only the ethanol extract exhibited a dose-dependent anti-inflammatory activity ranging between 11.1 and 23.6% at 200 mg/kg dose as well as displayed a significant antinociceptive activity without inducing any gastric damage. Although, both extracts were shown to possess significant DPPH radical-scavenging activity, that of aqueous extract was found to have more pronounced activity. In FIA-CL system, the ethanol extract was shown to possess a significant scavenger activity against H₂O₂ while the aqueous extract was much more potent antioxidant activity against HOCl-luminol CL than ethanol extract.

Conclusion

According to our results, it was concluded that Arctium minus ssp. minus contains potent natural antioxidants. In this study, in vivo experimental results have also supported the folk medicinal utilization of Arctium minus ssp. minus.     

Hypoglycaemic effects of Mammea africana (Guttiferae) in diabetic rats

Aim of the study

The stem bark of Mammea africana Sabine (Guttiferae) is used in African rain forest to treat various diseases, including diabetes mellitus. We investigated whether Mammea africana extract induced hypoglycaemic activity in rats.

Materials and methods

We tested the effects of acute (5 h) and sub-acute (21 days) oral administrations of the CH₂Cl₂–MeOH stem bark extract of Mammea africana (19–300 mg/kg body weight) on blood glucose levels of normal and streptozotocin (STZ)-induced type 1 diabetic rats. The effects were compared with those of glibenclamide.

Results

Acute administration reduced blood glucose in the diabetic rats only (33.87%, P < 0.01). Sub-acute treatment for 21 days also reduced blood glucose level in diabetic rats (73.29%, P < 0.01). A reduction or stabilization in total serum protein, triglyceride, cholesterol and alanine amino transferase levels was also observed. No effect was observed on body weight loss but food and water intakes were significantly reduced (P < 0.01) in diabetic rats. The maximal anti-diabetic effect was obtained with the dose of 75 mg/kg and was more important than that of glibenclamide.

Conclusion

It can be concluded that extracts of Mammea africana exhibited a significant anti-hyperglycaemic activity and improved the metabolic alterations in STZ-diabetic rats. These results provide a rationale for the use of Mammea africana to treat diabetes mellitus and hypercholesterolemia.     

In vitro biological activities of niloticane,a new bioactive cassane diterpene from the bark of Acacia nilotica subsp. kraussiana

Ethnopharmacological relevance

Acacia nilotica subsp. kraussiana was reported in African traditional medicine for the treatment of various ailments. Isolation of an active compound in this study from the bark extract may lead to the validation of its efficiency as a traditional crude drug.

Aims of the study

This study aimed to isolate active compound(s) from an ethyl acetate bark extract of Acacia nilotica subsp. kraussiana and to investigate some of its biological activity.

Materials and methods

The isolation process was carried out using bioassay-guided fractionation. The isolated compound was tested for antibacterial activity using the micro-dilution assay; anti-inflammatory activity using the COX-1 and COX-2 assays and investigated for inhibitory effect against acetylcholinesterase using the microplate assay.

Results

A new bioactive compound was isolated and identified as a cassane diterpene, niloticane. Niloticane showed antibacterial activity against Gram-positive bacteria Bacillus subtilis and Staphylococcus aureus with MIC values of 4 and 8 μg/mL, respectively. With Gram-negative bacteria, niloticane showed weak activity. MIC values obtained were 16 and 33 μg/mL against Klebsiella pneumonia and Escherichia coli, respectively. In the cyclooxygenase test, niloticane possessed activity with IC₅₀ values of 28 and 210 μM against COX-1 and COX-2, respectively. IC₅₀ values observed with indomethacin (positive control) were 3.6 μM for COX-1 and 189 μM for COX-2. In the acetylcholinesterase test, niloticane showed anti-cholinesterase activity with an IC₅₀ value of 4 μM. IC₅₀ values obtained by the galanthamine (positive control) was 2.0 μM.

Conclusion

The results obtained support the traditional uses of the bark of Acacia nilotica subsp. kraussiana in African traditional medicine for the treatment of some ailments that relate to microbial diseases, inflammation and central nervous system disorders.     

Antisecretory activity from the flowers of Chiranthodendron pentadactylon and its flavonoids on intestinal fluid accumulation induced by Vibrio cholerae toxin in rats

Ethnopharmacological relevance

The flowers of Chiranthodendron pentadactylon Larreat. (Sterculiaceae) has been traditionally used as folk medicine in Mexico for the treatment of gastrointestinal disorders such as diarrhea and dysentery.

Aim of the study

This study aimed to assess the antisecretory activity which supports the therapeutic use of Chiranthodendron pentadactylon and its flavonoids to treat diarrhea.

Materials and methods

The methanol extract of Chiranthodendron pentadactylon, subsequent fractions, and flavonoids were evaluated on cholera toxin-induced intestinal secretion in rat jejunal loops model.

Results

Three antisecretory flavonoids were isolated by bioassay-guided purification, namely, isoquercitrin 3, (+)-catechin 4 and (−)-epicatechin 5. Among them, epicatechin exhibited the most potent antisecretory activity with ID₅₀ of 8.3 μM/kg. Its potency was close that of to loperamide (ID₅₀ 6.1 μM/kg), drug used as control. Isoquercitrin (ID₅₀ 19.2 μM/kg) and catechin (ID₅₀ 51.7 μM/kg) showed moderate and weak activity, respectively.

Conclusion

The results of the present study lend some support to the anecdotal report for the traditional use of the flowers of Chiranthodendron pentadactylon in the control of dysentery.     

The antinociceptive activity of Polygonatumverticillatum rhizomes in pain models

Aim of the study

The current study was designed to establish the pharmacological rationale for the traditional use of the rhizomes of Polygonatum verticillatum in the treatment of painful conditions and as a plant diuretic.

Materials and methods

The crude methanolic extract of the rhizomes of Polygonatumverticillatum (PR) was tested in various established pain models in rodents at 50, 100 and 200 mg/kg i.p. while the diuretic activity was assessed at 300 and 600 mg/kg p.o. in rats.

Results

PR demonstrated significant reduction (14–72%) in the number of writhes induced by acetic acid in a dose-dependent manner. When nociceptive threshold was measured in the formalin test, PR strongly attenuated the formalin-induced flinching behaviour in both phases (6–30% in first phase while 12–72% in second phase). Central involvement in the analgesic profile of PR was confirmed by the hot plate test, in which PR elicited a significant (P < 0.01) analgesic activity by increasing latency time. However, an opioid receptor antagonist, naloxone (2 mg/kg s.c.) strongly antagonized the antinociceptive activity of PR. As a plant diuretic, PR showed mild but statistically insignificant diuretic activity at 300 mg/kg. The crude extract and solvent fractions of the plant contained reasonable quantity of total saponin and alkaloid contents.

Conclusions

The mechanisms underlying the analgesic action of PR shows that the opioid dependant central mediation has synergistic effect by enforcing the peripheral analgesic effects. Interestingly, our findings not only substantiated the folk use of the plant as an analgesic but also reported for the first time in the whole genus.     

Anti-nociceptive activity of Pereskia bleo Kunth. (Cactaceae) leaves extracts

Ethnopharmacological relevance

Local communities in Malaysia consume Pereskia bleo Kunth. (Cactaceae) leaves as raw vegetables or as a concoction and drink as a tea to treat diabetes, hypertension, rheumatism, cancer-related diseases, inflammation, gastric pain, ulcers, and for revitalizing the body.

Aim of the study

To evaluate anti-nociceptive activity of the extracts and vitexin, isolated for the first time in this species, in two analgesic models; formalin-induced licking and acetic acid-induced abdominal writhing.

Materials and methods

Three and a half kilos of P. bleo leaves were extracted using Soxhlet apparatus with ethanol for 72 h. The crude ethanol extract was treated with activated charcoal overnight and subjected to a liquid–liquid partition yielding hexane, dichloromethane, ethyl acetate and butanol extracts. All extracts, including the crude ethanol and vitexin isolated from the ethyl acetate partition were tested for peripheral anti-nociceptive activity using formalin test and acetic acid-induced abdominal writhing, besides having their acute toxicity assays performed.

Results

The phytochemical analyses resulted in the isolation of vitexin (1), β-sitosterol glucoside (2) and β-sitosterol (3) isolated from the ethyl acetate, dichloromethane and hexane extracts, respectively. This is the first time vitexin and β-sitosterol glucoside are isolated from this species. The anti-nociceptive activities for all extracts were only moderate. Vitexin, which was isolated from the ethyl acetate extract did not show any activity in all models tested when used alone at the same concentration as it appears in the extract.

Conclusion

This study showed that all the extracts possess moderate anti-nociceptive activity. Vitexin is not the compound responsible for the anti-nociceptive effect in the ethyl acetate extract. Further investigations are needed to identify the compound(s) that might be responsible for the anti-nociceptive activity in this plant.