Anti-inflammatory and antinociceptive activities of Homalium letestui

Abstract

Context. Homalium letestui Pellegr (Flacourtiaceae) is used in various decoctions traditionally by the Ibibios of the Niger Delta of Nigeria to treat stomach ulcer, malaria and other inflammatory diseases, as well as an aphrodisiac.

Objective: To investigate the anti-inflammatory and antinociceptive activities of the stem extract of the plant.

Materials and methods: The ethanol stem extract (500, 750, 1000?mg/kg, i.p.) of H. letestui was investigated for anti-inflammatory activity using carrageenan, egg albumin-induced and xylene-induced ear edema models and analgesic activity using acetic acid-induced writhing, formalin-induced paw licking and thermal-induced pain models. The ethanol extract was administered to the animals orally, 30?min to 1?h depending on the model, before induction of inflammation/pain. The LD₅₀ was also determined. GC–MS analysis of dichloromethane fraction was carried out.

Results: The extract caused a significant (p?<?0.05–0.001) reduction of inflammation induced by carrageenan (8.3–70.0%), egg albumin (10.0–71.42%) and xylene (39.39–84.84%). The extract also reduced significantly (p?<?0.05–0.001) pain induced by acetic acid (44.22–73.65%), formalin (55.89–79.21%) and hot plate (93.0–214.5%). The LD₅₀ was determined to be 4.38?±?35.72?g/kg.

Discussion and conclusion: The results of this study suggest that the ethanol stem extract of H. letestui possesses anti-inflammatory and analgesic properties which may in part be mediated through the chemical constituents of the plant as revealed by the GC–MS.     

Anti-inflammatory effect of Stereospermum suaveolens ethanol extract in rats

The anti-inflammatory effect of the ethanol extract of Stereospermum suaveolens (Roxb.) DC (Bignoniaceae) bark given orally at the dose of 200 and 400?mg/kg body weight was studied in rats using the carrageenan-, dextran-, and histamine-induced hind paw edema, and cotton pellet-induced granuloma formation models. Indomethcin at the dose of 10?mg/kg body weight was used as a standard drug. The extract (400?mg/kg body weight per os) showed maximum inhibition of edema 64.6, 53.48, and 50.06% at the end of 3?h with carrageenan-, dextran-, and histamine-induced rat paw edema, respectively. The extract (400?mg/kg) exhibited significant reduction (34.77%) in granuloma weight in the cotton pellet-induced granuloma model. From these results it could be concluded that, the ethanol extract of Stereospermum suaveolens possesses maximum anti-inflammatory activity in a dose-dependent manner, in various experimental models.     

Antinociceptive and anti-inflammatory effects of the ethyl acetate stem bark extract of Bridelia scleroneura (Euphorbiaceae)

Bridelia scleroneura is a member of the Euphorbiaceae family. In folk medicine in Cameroon, the stem bark of this plant is used for relieving abdominal pain, contortion, arthritis and inflammation. In this study, the antinociceptive and anti-inflammatory activities of the ethyl acetate stem bark extract have been evaluated. The putative analgesic effect of the plant extract was examined in abdominal constriction, hot plate, formalin and on pain using tail immersion mouse models and in carrageenan-induced paw edema in rats. The extract (150–600 mg/kg) exhibited a dose-dependent analgesic effect (46.27–78.97%) in acetic acid-induced abdominal constriction in mice. B. scleroneura extract increased the pain latency of nociceptive response to thermal stimuli at the higher dose of 600 mg/kg. B. scleroneuna induced significant dose-dependent reduction of the nociception in both early and late phases of the formalin test. The extract at the dose of 300 mg/kg, increased significantly, by 63.70% and 52.01% the tail-immersion latency time, 1 and 2 h post-dosing. In the carrageenan test, B. scleroneura (150–600 mg/kg, p.o) had dose-dependent and significant effects at different time intervals. This behaviour was similar to indometacin (10 mg/kg) used as a standard drug. These results show that the ethyl acetate stem bark extract of B. scleroneura possesses peripheral and central analgesic properties as well as anti-inflammatory activity against acute inflammation processes, in support of the folk medicinal use of the plant.     

Study of anti-inflammatory and antinociceptive activity of hydroalcoholic extract of Schima wallichii bark

Hydroalcoholic extract of Schima wallichii Choisy. (Ternstroemiaceae) bark (HESW) was investigated for its anti-inflammatory, antinociceptive, and antipyretic activities. The anti-inflammatory effects of the HESW were assayed by using carrageenan and dextran (acute model) induced paw edema and cotton pellet granuloma assay (chronic model) in experimental rats. Oral administration of HESW at the doses of 150 and 300?mg/kg caused dose-dependent inhibition of carrageenan and dextran induced inflammation. HESW at the doses of 150 and 300?mg/kg caused significant dose-dependent reduction of the granuloma tissue formation in experimental rats. The extract at the oral doses of 50 and 100?mg/kg body weight exhibited significant central and peripheral analgesic activity in acetic acid induced writhing test and hot-plate test respectively in experimental mice. Treatment with HESW at the oral doses of 150 and 300?mg/kg body weight significantly reduced the yeast-provoked elevated body temperature in experimental rats in a dose-dependent manner.     

An evaluation of the anti-inflammatory,antipyretic and analgesic effects of hydroethanol leaf extract of Albizia zygia in animal models

Context: The leaves of Albizia zygia (DC.) J.F. Macbr. (Leguminosae-Mimosoideae) are used in Ghanaian traditional medicine for the treatment of pain, inflammatory disorders and fever (including malaria).

Objectives: The present study evaluated the anti-inflammatory, antipyretic and analgesic effects of the hydroethanol leaf extract of Albizia zygia (AZE) in animal models.

Materials and methods: The anti-inflammatory and antipyretic effects of AZE were examined in the carrageenan-induced foot oedema model and the baker’s yeast-induced pyrexia test respectively. The analgesic effect and possible mechanisms of action were also assessed in the formalin test.

Results: AZE (30–300?mg/kg, p.o.), either preemptively or curatively, significantly inhibited carrageenan-induced foot edema in 7-day-old chicks (ED₅₀ values; preemptive: 232.9?±?53.33?mg/kg; curative: 539.2?±?138.28?mg/kg). Similarly, the NSAID diclofenac (10–100?mg/kg, i.p.) significantly reduced the oedema in both preemptive (ED₅₀: 21.16?±?4.07?mg/kg) and curative (ED₅₀: 44.28?±?5.75?mg/kg) treatments. The extract (30–300?mg/kg, p.o.) as well as paracetamol (150?mg/kg, p.o.) also showed significant antipyretic activity in the baker’s yeast-induced pyrexia test (ED₅₀ of AZE: 282.5?±?96.55?mg/kg). AZE and morphine (1–10?mg/kg, i.p.; positive control), exhibited significant analgesic activity in the formalin test. The analgesic effect was partly or wholly reversed by the systemic administration of naloxone, theophylline and atropine.

Conclusion: The results suggest that AZE possesses anti-inflammatory, antipyretic and analgesic properties, which justifies its traditional use. Also, the results show the involvement of the opioidergic, adenosinergic and the muscarinic cholinergic pathways in the analgesic effects of AZE.     

Antinociceptive and anti-inflammatory effects of the aerial parts of Artemisia dracunculus in mice

Context: Tarragon (Artemisia dracunculus L., Asteraceae) is an ancient herb, which is widely used as a medicine, flavoring, or fragrance.

Objective: To determine the antinociceptive and anti-inflammatory effects of aerial parts of tarragon, we investigated the effects of ethanolic extract of the plant in adult male Balb/c mice.

Materials and methods: Antinociceptive activity was determined using formalin, hot-plate, and writhing tests. The effect of the ethanolic extract on acute inflammation was evaluated by xylene-induced ear edema in mice. The ethanolic extract was administered at doses of 5, 10, 50, and 100?mg/kg, i.p. The control group received saline as vehicle of ethanolic extract.

Results: Our results showed that the ethanolic extract (50 and 100?mg/kg) decreased both phases of pain in the formalin test (ED₅₀?=?109.66 and 87.13?mg/kg, respectively). In the hot-plate test, the extract (50 and 100?mg/kg) increased pain threshold during 60?min (ED₅₀?=?81.03?mg/kg). The extract (50 and 100?mg/kg) exhibited antinociceptive activity against acetic acid-induced writhing (ED₅₀?=?66.99?mg/kg). The extract (50 and 100?mg/kg) showed significant activity in the xylene ear edema test (ED₅₀?=?78.20?mg/kg). Pretreatment of the animals with naloxone decreased the analgesia induced by the extract in hot-plate and formalin tests; therefore, opioid receptors may be involved, at least partly, in the analgesic effect of tarragon extract.

Discussion and conclusion: The results suggested that tarragon have significant analgesic and anti-inflammatory effects in mice, and, therefore, further studies are required to evaluate these effects and additional potential of the plant.     

Antinociceptive and anti-inflammatory effects of the ethanol extract of Alpinia conchigera rhizomes in various animal models

Alpinia conchigera Griff. (Zingiberaceae), locally known to the Malays as “lengkuas ranting”, is native to Peninsular Malaysia. The Malays traditionally used it to treat infection and rashes, and as a health drink. This study evaluated the analgesic and anti-inflammatory activities of the ethanol extract of A. conchigera rhizomes in mice and rats, respectively. The analgesic activity was elucidated using the acetic acid-induced writhing test, hot plate test, and formalin test, while the anti-inflammatory activity was determined using carrageenan-induced paw edema. The extract (30, 100, and 300?mg/kg) given intraperitoneally (i.p.) exhibited antinociceptive and anti-inflammatory activities in all tests used. The range of percentage of analgesia obtained for all doses of extract in the writhing test was 50–92%, and in the early and late phases of the formalin test was 25–62% and 63–98%, respectively. In addition, naloxone (5?mg/kg) given subcutaneously (s.c.) was found to reverse the extract (300?mg/kg)-induced antinociceptive activity in the writhing, hot plate, and formalin tests. Based on the results obtained, it can be concluded that the ethanol extract of A. conchigera rhizomes possessed a peripheral and central antinociceptive activity that was mediated, in part, via the opioid receptor, as well as anti-inflammatory activity.     

Screening of Bauhinia purpurea Linn. for analgesic and anti-inflammatory activities

Objectives:

Ethanol extract of the stem of Bauhinia purpurea Linn. was subjected to analgesic and anti-inflammatory activities in animal models.

Materials and Methods:

Albino Wistar rats and mice were the experimental animals respectively. Different CNS depressant paradigms like analgesic activity (determined by Eddy''s hot plate method and acetic acid writhing method) and anti-inflammatory activity determined by carrageenan induced paw edema using plethysmometer in albino rats) were carried out, following the intra-peritoneal administration of ethanol extract of Bauhinia purpurea Linn. (BP) at the dose level of 50 mg/kg and 100 mg/kg.

Results:

The analgesic and anti-inflammatory activities of ethanol extracts of BP were significant (P < 0.001). The maximum analgesic effect was observed at 120 min at the dose of 100 mg/kg (i.p.) and was comparable to that of standard analgin (150 mg/kg) and the percentage of edema inhibition effect was 46.4% and 77% for 50 mg/kg and 100 mg/kg (i.p) respectively. Anti-inflammatory activity was compared with standard Diclofenac sodium (5 mg/kg).

Conclusion:

Ethanol extract of Bauhinia purpurea has shown significant analgesic and anti-inflammatory activities at the dose of 100 mg/kg and was comparable with corresponding standard drugs. The activity was attributed to the presence of phytoconstituents in the tested extract.     

Anti-inflammatory and Analgesic Effects of Drypemolundein A,a Sesquiterpene Lactone from Drypetes molunduana

Previous pharmacological screening in our laboratory showed analgesic and anti-inflammatory effects of a crude stem bark extract of Drypetes molunduana. Phytochemical studies of this plant led to the isolation an structural elucidation of seven pentacylic triterpenes and one lignan, which were already known compounds, and a new furanosesquiterpene lactone, Drypemolundein A. The purpose of this study was to examine the anti-inflammatory and analgesic activities of drypemolundein A. The compound was studied against carrageenan-induced acute edema. At doses of 10 and 20 mg/kg, orally administered, it significantly reduced (57.57 and 66.66% inhibition at 1 h intervals, respectively) paw edema. At the same doses, this sesquiterpene lactone also exhibited significant analgesic action in force-induced pain in rat paw. These results indicate that drypemolundein A functions as an effective anti-inflammatory and analgesic agent.     

Antinociceptive and anti-inflammatory activities of Viburnum opulus

Water extract of Viburnum opulus L. (Caprifoliaceae) (VO) leaf was investigated for antinociceptive and anti-inflammatory activities in mice and rats. The tail flick test, acetic acid-induced writhing test, and the carrageenan-induced rat paw edema test were used to determine these effects. Our findings show that VO causes dose related inhibition in acetic acid-induced abdominal stretching in mice. VO inhibited abdominal stretching at 100 and 200?mg/kg. VO showed antinociceptive activity, which was quantified by the tail-flick test at doses of 100 and 200?mg/kg. However, VO did not have an anti-inflammatory effect at these doses. The LD₅₀ of VO was determined as 5.447?g/kg.     

Analgesic and anti-inflammatory activities of Polygonum stagninum

The n-hexane, ethyl acetate (EtOAc), and methanol extracts of the aerial parts of Polygonum stagninum Buch.-Ham. ex Meissn. (Polygonaceae), a Bangladeshi medicinal plant, were assessed for analgesic and anti-inflammatory properties in experimental mice and/or rat models. In the acetic-acid-induced writhing test in mice, all extracts displayed a dose dependent analgesic effect. The most potent analgesic activity was observed with the EtOAc extract at the dose of 400?mg/kg body weight, with an inhibition of writhing response of 50.3% compared to 62.2% for the positive control aminopyrine. Among the extracts, n-hexane extract at the doses of 200 and 400?mg/kg body weight showed the highest levels of anti-inflammatory activity after 2?h, with the inhibition of paw edema of 60.1% and 64.1%, respectively, and this effect was much better than that of the conventional anti-inflammatory agent phenylbutazone (maximum inhibition of 38.3% after 4?h).     

Antimicrobial and anti-inflammatory properties of Funtumia elastica

Context: Funtumia elastica (Preuss) Stapf. (Apocynaceae) has a long ethnopharmacological history for uses such as treatment of whooping cough, asthma, blennorhea, painful menstruation, fungal infections, and wounds.

Objective: To investigate the antimicrobial and anti-inflammatory properties of ethanol extracts from the leaves and stem bark of Funtumia elastica based on its ethnopharmacological uses and also determine the secondary metabolites present in the extracts.

Materials and methods: The antimicrobial activities of ethanol leaf and bark extracts of F. elastica were determined using the microdilution technique (MIC determination) and agar diffusion method using 10, 25, and 50?mg/mL concentrations against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, Candida albicans, Aspergillus flavus and Aspergillus niger as test organisms. Anti-inflammatory activities of the doses of extracts at 30, 100, and 300?mg/kg per body weight were determined by carrageenan-induced edema in the footpad of 7-day-old chicks and the foot volumes measured at hourly interval post-treatment for 5?h.

Results: The MIC ranges of both ethanol leaf and bark extracts against the test organisms were 125 (lowest MIC) to1550 µg/mL (highest MIC) and 125 (lowest MIC) to 1750 µg/mL (highest MIC), respectively. The ethanol leaf and bark extract of F. elastica showed significant anti-inflammatory activity (p ≤ 0.001) at 30, 100 and 300?mg/kg. Preliminary phytochemical screening revealed that F. elastica bark contains hydrolysable tannins, sapogenetic glycosides, steroids and saponins while the leaves contain hydrolysable tannins, flavonoids, starch and alkaloids. Tannin contents of the leaf and stem bark were 2.4 and 1.3% w/w (related to the dried material), respectively.

Discussion and conclusion: Both ethanol leaf and bark extracts of F. elastica showed antimicrobial and anti-inflammatory activities and these pharmacological properties may be responsible for the ethnomedicinal uses of the leaves and stem bark of the plant.     

The antinociceptive and anti-inflammatory effects of Salvia officinalis leaf aqueous and butanol extracts

Context: The leaf of sage Salvia officinalis L. (Lamiaceae) is reputed in the folk medicine of Arabia, and Jordan in particular, to relieve pain associated with gastrointestinal disturbance.

Objectives: Evaluation of the antinociceptive and anti-inflammatory activities of aqueous and butanol extracts of S. officinalis leaf.

Materials and methods: The analgesic effects of the aqueous extract (10, 31.6, 100, 316, 1000?mg/kg) and butanol extract (10, 31.6, 100, 316?mg/kg) were studied using the hot-plate test for mice and the formalin-induced paw licking in rats. The effects were compared to those of morphine and the influence of naloxone on these effects was also evaluated. The same concentrations of both extracts were used to evaluate their anti-inflammatory effects using the cotton pellet granuloma and carrageenan-induced paw edema in rats.

Results: The aqueous extract (10, 31.6, 100, 316, 1000?mg/kg) and butanol extract (10, 31.6, 100, 316?mg/kg) caused analgesic effect in the hot-plate latency assay as well as in early and late phases of formalin-induced paw licking in rats. These effects were reduced by the opioid receptor antagonist, naloxone (5?mg/kg). The same range of doses of both extracts caused dose-dependent inhibition of carrageenan-induced paw edema in rats as well as inhibition of cotton pellet granuloma.

Discussion and conclusion: These observations suggest that the sage leaf aqueous and butanol extracts have analgesic and anti-inflammatory effects, confirming the traditional use of this plant for pain alleviation.     

Anti-inflammatory,analgesic, and antioxidant activities of Pisonia aculeata: Folk medicinal use to scientific approach

Context: Pisonia aculeata leaves (Nyctagenaceae), a Folk medicinal plant used in the treatment of several inflammation, pain, and oxidative stress associated diseases.

Objective: To evaluate anti-inflammatory, analgesic, and antioxidant potential of crude methanol extract of P. aculeata leaves (MEPA).

Materials and methods: Analgesic and anti-inflammatory activities of MEPA (250 and 500?mg/kg) were evaluated using writhing, formalin, hot plate, tail flick, carrageenan-induced paw edema test, and membrane stabilizing activity. Free radical scavenging activity, total phenolic and flavonoid contents of MEPA were also determined using standard methods.

Results: Oral administration of MEPA showed significant (p < 0.001) inhibition of paw edema, pronounced at 4?h and 5?h after carrageenan injection, and at 200 µg/mL exerts 77.67 and 38.51% protective effect against hypotonic solution and heat induced hemolysis, respectively. MEPA (250 and 500?mg/kg) produced 35.21 and 79.14% inhibition of acetic acid-induced writhing. Furthermore, MEPA (500?mg/kg) inhibited 49.19% early and 73.14% late phase of formalin-induced hypernociception. In contrast, a lower dose of MEPA did not prevent hot plate induced nociception, while in the tail immersion method, pronounced analgesic activity was observed between 1 and 4?h postdosing. The extract possesses significant in vitro antioxidant activity and a lipid peroxidation inhibition effect. Total phenolic and total flavonoid content in MEPA were 87.99?±?0.87?mg GAE/g and 58.98?±?0.01?mg QE/g, respectively.

Discussion and conclusion: Our findings confirmed the analgesic, anti-inflammatory and antioxidant activities of Pisonia aculeata leaves. Contents of flavonoids and phenolic compounds in extract could be correlated with its observed biological activities.     

Analgesic and anti-inflammatory effects of the methanol root extracts of some selected Nigerian medicinal plants

Context: The roots of Alafia barteri Oliver (Apocynaceae), Combretum mucronatum Schumach (Combretaceae) and Capparis thonningii Schum (Capparaceae) are used in Traditional African Medicine to alleviate painful and inflammatory conditions.

Objective: This study investigated the analgesic and anti-inflammatory effects of the methanol root extracts of Alafia barteri (MeAB), C. mucronatum (MeCM), and Capparis thonningii (MeCT).

Materials and methods: Analgesic activity of the extracts (50, 100, and 200?mg/kg, p.o. 1?h) was evaluated using acetic acid-, formalin- and hot plate-induced pain while anti-inflammatory actions (100 or 200?mg/kg) were investigated using the carrageenan- and xylene-induced edema tests.

Results: MeAB, MeCM, and MeCT (200?mg/kg) inhibited acetic acid-induced abdominal constriction by 55.07, 46.67, and 47.25%, respectively. In the formalin test, the index of pain inhibition of early and late phases was, respectively, 47.83 and 81.98% for MeAB, 56.10 and 63.81% for MeCM, and 42.84 and 63.29% for MeCT (200?mg/kg). MeAB and MeCT pretreatments significantly increased the reaction time by 46.67 and 25.53%, respectively, 120?min post-treatment in the hot-plate test. Naloxone (5?mg/kg, s.c.) pretreatment 15?min before extract administration, significantly (p?MeAB, MeCM, and MeCT showed significant anti-inflammatory activity with 60.44 and 30.39%, 63.74 and 58.08%, and 50.55 and 77.84% (200?mg/kg, 4?h), respectively, inhibition of paw and ear edema.

Discussion and conclusion: The analgesic and anti-inflammatory effects of MeAB and MeCT involve an interaction with opioid pathway and/or inhibition of chemical mediators of pain and inflammation.     

Bioassay-guided isolation of anti-inflammatory and antinociceptive compound from Plumbago zeylanica leaf

Plumbago zeylanica Linn. (Plumbaginaceae) is used in the treatment of various inflammatory ailments in traditional medicines. In order to validate these ethnobotanical practices, the anti-inflammatory and antinociceptive activities of various leaf extracts (petroleum ether (60–80°), chloroform, acetone, ethanol, and aqueous) were studied using in vivo experimental models at two dose levels (200 and 400?mg/kg, p.o.). Anti-inflammatory activity was tested using the carrageenan induced rat hind paw edema method while analgesic activity was studied using the hot plate and formalin induced models. Diclofenac (100?mg/ kg) was used as the reference standard in both anti-inflammatory and analgesic models and morphine (10?mg/ kg, i.p.) was used as the reference standard in the formalin induced analgesic model. The acetone extract significantly (p?<?0.01) reduced inflammation in the rats when compared to the control group. As for the analgesia effect, the acetone and petroleum ether extracts significantly (p?<?0.01) decreased the pain stimulus only in the later phase of the formalin test, suggesting that the drug could be peripherally acting. Bioassay-guided fractionation of the acetone extract led to the isolation and identification of plumbagin. Structure elucidation of plumbagin confirmed it as 5-hydroxy-2-methyl-1,4-naphthoquinone, a naphthaquinone derivative, through spectral techniques.     

Comparative study of the anti-inflammatory and antinociceptive effects of two varieties of Punica granatum

Context: Studies have shown that pomegranate, Punica granatum Linn. (Lythraceae), has remarkable biological and medicinal properties.

Objective: This work aimed to explore and compare the analgesic and anti-inflammatory activities of the methanol extract (MoE) obtained from fruit peels of two varieties of pomegranate: Amrouz (MoEA) and Sefri (MoES).

Materials and methods: Antinociceptive activity of MoEA and MoES was examined using four models of pain. The extracts were administered by the intraperitoneal route (i.p.) in writhing (50, 100 and 150?mg/kg) and formalin tests (25, 50 and 100?mg/kg) and by intra-cerebroventricular injection (i.c.v.) in hotplate and tail-immersion tests (10, 25 and 50 µg/3 µl/rat). anti-inflammatory activity was studied using the hind paw egg albumin test (50, 100 and 150?mg/kg, i.p.).

Results: In the writhing test, the index of pain inhibition (IPI) was 52% for MoEA (150?mg/kg, i.p.) and 29% for MoES (150?mg/kg, i.p.). In the formalin test, the IPI of early and late phase were, respectively, 75% and 82% for MoEA (100?mg/kg, i.p.) and 8% and 63% for MoES (100?mg/kg, i.p.). In the hotplate and tail-immersion test, MoEA and MoES increased in a dosedependent manner the reaction latency to the thermal stimuli. MoEA seems to be more potent than MoES. Only the analgesic effect of MoEA was partially inhibited by pretreatment with naloxone. Both extracts exerted a significant anti-inflammatory effect.

Discussion and conclusions: The results demonstrated that P. granatum contains active constituents, which possess antinociceptive and anti-inflammatory activity, justifying its popular uses.     

Analgesic and anti-inflammatory effects of the methanol stem bark extract of Prosopis africana

Prosopis africana (Guill. & Perr.) Taub. (Mimosoideae) is a shrub used for menstrual and general body pain in Nupe land in north central Nigeria. In this study, the methanol extract of the stem bark of Prosopis africana (at doses of 62.5, 125, and 250?mg/kg) was evaluated for analgesic and anti-inflammatory activities using acetic acid-induced writhing assay and carrageenan-induced inflammation in rats. The extract significantly (P <0.05) attenuated the acetic acid-induced writhing with the highest activity observed at the highest dose, 250?mg/kg (76.89%) comparable to that of piroxicam (83.16%) the standard agent used. In the carrageenan-induced inflammation assay, the extract showed significant anti-inflammatory activity (P <0.001) from the third hour. The preliminary phytochemical screening revealed the presence of flavonoids, saponins, carbohydrates, cardiac glycosides, tannins, and alkaloids. The oral median lethal dose was found to be 3807.9?mg/kg in mice and > 5000?mg/kg in rats. This study supports the folkloric claim of the use of Prosopis africana in the management of pain.     

beta-Amyrin and alpha-amyrin acetate isolated from the stem bark of Alstonia boonei display profound anti-inflammatory activity

Context: Alstonia boonei De Wild (Apocyanaceae) is used in ethnomedicine for the management of malaria, ulcer, rhematic pain, toothache, and inflammatory disorders.

Objective: To investigate the anti-inflammatory potential of β-amyrin and α-amyrin acetate isolated from the stem bark of Alstonia boonei using animal models.

Materials and methods: Chromatographic purification of the crude methanol extract led to the isolation and structure elucidation of β-amyrin and α-amyrin acetate. Their anti-inflammatory activities were evaluated in rodents using egg albumen-induced paw edema and xylene-induced ear edema models. The gastric ulcerogenic, in vivo leucocyte migration, and RBC membrane stabilization tests were also investigated.

Results: α-Amyrin acetate at 100?mg/kg showed significant (p?p?>?0.01) irritation of the gastric mucosa while significant (p?p?p?Discussion and conclusion: This study generally provided evidence of profound anti-inflammatory activity of β-amyrin and α-amyrin acetate isolated from the Alstonia boonei stem bark.     

Anticonvulsant activity of aqueous fraction of Carissa edulis root bark

Abstract

Context: Carissa edulis Vahl (Apocynaceae) is used in Nigerian folk medicine to manage a plethora of diseases including epilepsy, cancer, and inflammation; its efficacy is widely acclaimed among communities of northern Nigeria.

Objective: This study establishes anticonvulsant activities of aqueous fraction of ethanol root bark extract of Carissa edulis (RAF) and sub-fractions (S1 and S2) in animal models.

Materials and methods: We evaluated the acute toxicity of the RAF, S1 and S2, and the anticonvulsant activity using pentylenetetrazole (PTZ), picrotoxin, strychnine, N-methyl-d-aspartate (NMDA), isoniazid (INH), and aminophylline-induced seizures in mice. Their effects on maximal electroshock (MES) and kindling-induced seizures were studied in chicks and in rats, respectively, and in the electrophysiological study. The doses used for RAF were 150, 300, and 600?mg/kg while S1 and S2 were 250, 500, and 1000?mg/kg. Both RAF and sub-fractions were administered once during the experiment.

Results: The intraperitoneal LD₅₀ of the RAF was estimated to be 2222.61?mg/kg and that of the S1 and S2 were above 5000?mg/kg. RAF protected the mice by 50% while sub-fractions by 16.67% against PTZ-induced seizures. RAF offered 33.33 and 16.67% protection against strychnine and NMDA models, respectively. However, RAF offered 66.67–33.33% protections against aminophylline-induced seizures at doses of 150 and 600?mg/kg, but RAF, S1, and S2 had no effect on MES-induced seizures.

Discussion and conclusion: Our results validate the use of the plant traditionally in the management of epilepsy, thus supporting the appraisal of biologically active components of this plant as antiepileptic agents.