Antinociceptive, anti-inflammatory and antidiabetic properties of Hypoxis hemerocallidea Fisch. & C.A. Mey. (Hypoxidaceae) corm ['African Potato'] aqueous extract in mice and rats

In order to scientifically appraise some of the anecdotal, folkloric, ethnomedical uses of Hypoxis hemerocallidea Fisch. & C.A. Mey. (Hypoxidaceae) corm ['African Potato'], the present study was undertaken to examine the antinociceptive, anti-inflammatory and antidiabetic properties of the corm's aqueous extract (APE) in mice and rats. The antinociceptive effect of APE was evaluated by 'hot-plate' and 'acetic acid' analgesic test methods in mice; while the anti-inflammatory and antidiabetic effects of the plant's extract were investigated in rats, using fresh egg albumin-induced pedal (paw) oedema, and streptozotocin (STZ)-induced diabetes mellitus models. Morphine (MPN, 10 mg/kg), diclofenac (DIC, 100 mg/kg) and chlorpropamide (250 mg/kg) were used as reference drugs for comparison. H. hemerocallidea corm aqueous extract (APE, 50-800 mg/kg i.p.) produced dose-dependent, significant (P < 0.05-0.001) antinociceptive effects against thermally- and chemically-induced nociceptive pain stimuli in mice. The plant extract (APE, 50-800 mg/kg p.o.) also significantly (P < 0.05-0.001) inhibited fresh egg albumin-induced acute inflammation, and caused dose-related, significant (P < 0.05-0.001) hypoglycaemia in normal (normoglycaemic) and diabetic rats. The results obtained in this study suggest that the antinociceptive effects of the plant's extract are peripherally- and centrally-mediated. The findings of this experimental animal study indicate that H. hemerocallidea corm aqueous extract (APE) possesses antinociceptive, anti-inflammatory and antidiabetic properties; and thus lend pharmacological support to folkloric, anecdotal uses of 'African Potato' in the treatment and/or management of painful, arthritic inflammatory conditions, as well as in the management and/or control of type-2 diabetes mellitus in some parts of southern Africa.     

Analgesic, anti-inflammatory and hypoglycaemic effects of Rhus chirindensis (Baker F.) [Anacardiaceae] stem-bark aqueous extract in mice and rats

In an attempt to scientifically evaluate some of the anecdotal, folkloric, ethnomedical uses of Rhus chirindensis Baker F. ('red currant'), the present study was undertaken to investigate the analgesic, anti-inflammatory and hypoglycaemic effects of the plant's stem-bark aqueous extract (RCE) in mice and rats. The analgesic effect of RCE was evaluated by 'hot-plate' and 'acetic acid' analgesic test methods in mice; while its anti-inflammatory and hypoglycaemic effects were investigated in rats, using fresh egg albumin-induced pedal oedema, and streptozotocin (STZ)-induced diabetes mellitus animal models. Morphine (MPN, 10 mg/kg), diclofenac (DIC, 100 mg/kg) and chlorpropamide (250 mg/kg) were used as reference drugs for comparison. RCE (50-800 mg/kg i.p.) produced dose-dependent, significant (P<0.05-0.001) analgesic effects against thermally- and chemically-induced nociceptive pain in mice. The plant's extract (RCE, 50-800 mg/kg p.o.) also significantly (P<0.05-0.001) inhibited fresh egg albumin-induced acute inflammation, and caused dose-related, significant (P<0.05-0.001) hypoglycaemia in normal (normoglycaemic) and diabetic (hyperglycaemic) rats. The flavonoids, triterpenoids and other chemical compounds present in RCE are speculated to account for the observed pharmacological effects of the plant's extract in the experimental animal paradigms used. The findings of this experimental animal study indicate that Rhus chirindensis stem-bark aqueous extract possesses analgesic, anti-inflammatory and hypoglycaemic properties; and thus lend pharmacological credence to the anecdotal, folkloric, ethnomedical uses of the plant in the treatment and/or management of painful, arthritic, inflammatory conditions, as well as in the management and/or control of type 2 diabetes mellitus in some rural communities of South Africa.     

Evaluation of the analgesic, anti-inflammatory and anti-diabetic properties of Sclerocarya birrea (A. Rich.) Hochst. stem-bark aqueous extract in mice and rats

In order to appraise some of the ethnomedical uses of Sclerocarya birrea (A. Rich.) Hochst., subspecies caffra (Sond.) Kokwaro [family: Anacardiaceae], the present study was undertaken to investigate the analgesic, anti-inflammatory and anti-diabetic properties of the plant's stem-bark aqueous extract in experimental models of pain, inflammation and diabetes mellitus. The analgesic effect of Sclerocarya birrea stem-bark aqueous extract was evaluated in mice, while its anti-inflammatory and anti-diabetic effects were investigated in rats. Diclofenac (DIC, 100 mg/kg p. o.) and chlorpropamide (250 mg/kg p. o.) were used respectively as reference analgesic, anti-inflammatory and anti-diabetic agents for comparison. Like diclofenac (DIC, 100 mg/kg p. o.), Sclerocarya birrea stem-bark aqueous extract (SBE, 100-800 mg/kg p. o.) produced dose-dependent, significant protection (p < 0.05-0.001) against electrical heat-induced pain. The plant extract (SBE, 25-800 mg/kg p. o.) also produced dose- and time-related, sustained and significant reductions (p < 0.05-0.001) in the fresh egg albumin-induced acute inflammation of the rat hind paw oedema. However, the analgesic and anti-inflammatory effects of the plant's extract were found to be approximately 10-15 times less than that of diclofenac. In one set of experiments involving hypoglycaemic/antidiabetic evaluation of the plant's extract, graded doses of Sclerocarya birrea stem-bark aqueous extract (SBE, 25-800 mg/kg p. o.) were separately administered to groups of fasted normal and fasted diabetic rats. In another set of experiments, a single dose of the plant's aqueous extract (SBE, 800 mg/kg p. o.) was used. The hypoglycaemic effect of this single dose of Sclerocarya birrea stem-bark aqueous extract (SBE, 800 mg/kg p. o.) was compared with that of chlorpropamide (250 mg/kg p. o.) in both fasted normal and fasted streptozotocin (STZ)-treated diabetic rats. Following acute treatment, relatively moderate to high doses of Sclerocarya birrea stem-bark aqueous extract (SBE, 25-800 mg/kg p. o.) produced dose-dependent, significant reductions (p < 0.05-0.001) in the blood glucose concentrations of both fasted normal and fasted diabetic rats. Chlorpropamide (250 mg/kg p. o.) also produced significant reductions (p < 0.05-0.001) in the blood glucose concentrations of the fasted normal and fasted diabetic rats. Administration of the single dose of Sclerocarya birrea stem-bark aqueous extract (SBE, 800 mg/kg p. o.) significantly reduced (p < 0.01-0.001) the blood glucose levels of both fasted normal (normoglycaemic) and fasted STZ-treated, diabetic rats. The results of this experimental animal study indicate that Sclerocarya birrea stem-bark aqueous extract possesses analgesic, anti-inflammatory and hypoglycaemic properties. These experimental findings lend pharmacological support to the suggested folkloric uses of the plant's stem-bark in the management and/or control of pain, inflammatory conditions, and adult-onset, type-2 diabetes mellitus in some communities of South Africa.     

Analgesic, antiinflammatory and antidiabetic properties of Harpagophytum procumbens DC (Pedaliaceae) secondary root aqueous extract

South Africa is blessed with a rich floral biodiversity of medicinally useful plants. One such plant is Harpagophytum procumbens DC (Family: Pedaliaceae). H. procumbens is widely used in South African traditional medicine for the treatment, management and/or control of a variety of human ailments. In the present study, the analgesic effect of H. procumbens secondary root aqueous extract was evaluated in mice, using the 'hot-plate' and 'acetic acid' test methods; while the antiinflammatory and antidiabetic effects of the plant's secondary root extract were investigated in rats. Fresh egg albumin-induced pedal oedema and streptozotocin (STZ)-induced diabetes mellitus were used as experimental test models of inflammation and diabetes Diclofenac (DIC, 100 mg/kg i.p.) was used as a reference analgesic and antiinflammatory agent for comparison. Chlorpropamide (250 mg/kg p.o.) was used as a reference hypoglycaemic agent for comparison. H. procumbens root aqueous extract (HPE, 50-800 mg/kg i.p.) produced significant (p < 0.05-0.001) analgesic effects against thermally and chemically induced nociceptive pain stimuli in mice. H. procumbens root extract (HPE, 50-800 mg/kg i.p.) also produced dose-related, significant reductions (p < 0.05-0.001) of the fresh egg albumin-induced acute inflammation of the rat hind paw oedema. Furthermore, the plant extract (HPE, 50-800 mg/kg i.p.) produced dose-dependent, significant reductions (p < 0.05-0.001) in the blood glucose concentrations of both fasted normal and fasted diabetic rats. The results of this experimental animal study indicate that H. procumbens root aqueous extract possesses analgesic, antiinflammatory and hypoglycaemic properties, and lend pharmacological support to the suggested folklore uses of Harpagophytum procumbens root in the management and/or control of painful, arthritic and other inflammatory conditions, as well as for adult-onset, type-2 diabetes mellitus in some communities of South Africa.     

Antinociceptive and anti-inflammatory effects of Elaeagnus angustifolia fruit extract

In this study, probable antinociceptive and anti-inflammatory effects of Elaeagnus angustifolia fruit components, were evaluated. For evaluation of antinociceptive effects, the chronic (formalin test) and acute (tail-flick) pain models of rats were used. For the anti-inflammatory effects, the paw inflammation model was used through subcutaneous injection of 5% formalin to the paw of male rats. Water extracts of the fruit and its components in the single dose were assessed through comparison with the antinociceptive and anti-inflammatory effects of sodium salicylate (SS) as a positive control. Administration of 300 mg/kg of SS (i.p.) had no effect on tail flick latency, while 1000 mg/kg of total (i.p. and p.o.) and endocarp (i.p.) extract, increased this latency (P<0.01, P<0.001, respectively), which was not reversed by naloxone (2 mg/kg). In the formalin test, SS (300 mg/kg, i.p.) and the extract (1000 mg/kg, p.o. ) alleviated the animals nociception in the second phase, while in the first phase they were not effective. The total and endocarp extracts (1000 mg/kg, i.p.) showed a significant effect on both phases (P<0.01, P<0.001, respectively) which was also not reversed by naloxone (2 mg/kg, i.p.). In the acute anti-inflammatory test, the total extract and the aqueous extract of individual fruit components showed a significant effect (P<0.001). This anti-inflammatory effect was not significant compared with the anti-inflammatory effect of SS. Because of the extract effect on the tail-flick latency and both phases of the formalin test, the site of its analgesic action is probably central, and the mechanism of antinociceptive action of the extract are not related to the opioid system. Our phytochemical studies indicated that aqueous extract of E. angustifolia fruit contains flavonoids, terpenoids and cardiac glycosides.     

Pharmacological evidence favouring the folkloric use of Diospyros mespiliformis Hochst in the relief of pain and fever

The methanol extract of Diospyros mespiliformis was evaluated for its claimed folkloric usage in the relief of pain and fever. Antipyretic, analgesic and anti-inflammatory effects of the extract were evaluated in rats and mice. Studies were carried out on yeast-induced pyrexia in rats, acetic acid-induced writhing in mice, formalin test and egg albumin-induced anti-inflammatory activity in rats. The extract (50 and 100 mg/kg i.p.) gave a potent antipyretic effect for 100 mg/kg and significant activity (P<0.05) against all the analgesic and anti-inflammatory models used. The LD(50) of the extract was estimated to be 513.80+/-33.92 mg/kg i.p. in mice. These results provide support for the use of the plant in relieving pain and fever.     

Anticonvulsant effect of Persea americana Mill (Lauraceae) (Avocado) leaf aqueous extract in mice

Various morphological parts of Persea americana Mill (Lauraceae) (avocado) are widely used in African traditional medicines for the treatment, management and/or control of a variety of human ailments, including childhood convulsions and epilepsy. This study examined the anticonvulsant effect of the plant's leaf aqueous extract (PAE, 50-800 mg/kg i.p.) against pentylenetetrazole (PTZ)-, picrotoxin (PCT)- and bicuculline (BCL)-induced seizures in mice. Phenobarbitone and diazepam were used as reference anticonvulsant drugs for comparison. Like the reference anticonvulsant agents used, Persea americana leaf aqueous extract (PAE, 100-800 mg/kg i.p.) significantly (p < 0.05-0.001) delayed the onset of, and antagonized, pentylenetetrazole (PTZ)-induced seizures. The plant's leaf extract (PAE, 100-800 mg/kg i.p.) also profoundly antagonized picrotoxin (PCT)-induced seizures, but only weakly antagonized bicuculline (BCL)-induced seizures. Although the data obtained in the present study do not provide conclusive evidence, it would appear that 'avocado' leaf aqueous extract (PAE) produces its anticonvulsant effect by enhancing GABAergic neurotransmission and/or action in the brain. The findings of this study indicate that Persea americana leaf aqueous extract possesses an anticonvulsant property, and thus lends pharmacological credence to the suggested ethnomedical uses of the plant in the management of childhood convulsions and epilepsy.     

Antinociceptive and anti-inflammatory effect of the aqueous extract from leaves of Pimenta racemosa var. ozua (Mirtaceae)

The leaves of Pimenta racemosa var. ozua (Urban & Ekman) Landrum L. (Myrtaceae) are used against the pain and the inflammation in popular medicine of the Caribe area. In the present work, the antinociceptive, anti-inflammatory effect, and acute toxicity of the aqueous extract from leaves of Pimenta racemosa have been investigated. The antinociceptive action was assayed in several experimental models in mice: acetic acid, formalin, and hot plate tests. The aqueous extract (125 and 250 mg/kg) significantly and in a dose-dependent manner reduced the nociception induced by the acetic acid intraperitoneal injection (P<0.001). In the formalin test, the extract also significantly reduced the painful stimulus in both phases of the test (P<0.001). On the contrary, the extract neither significantly increased the latency time of licking nor jumping in the hot plate test. In the anti-inflammatory study, the plant also showed an interesting effect. Aqueous extract (125 and 250 mg/kg) orally administered, significantly reduced the carrageenan-induced edema in rat paw at 1, 3, and 5 h (P<0.001). In the TPA test the edema was dose-dependent and significantly reduced by the extract (0.5, 1, and 3 mg per ear) when it was topically applied (P<0.01; P<0.001). The levels of myeloperoxidase enzyme also were reduced in the inflamed tissue by the extract. Acute toxicity also was investigated and the results indicated a moderate toxicity (LD50: 287 +/- 12.9 mg residue/kg; 1.854 +/- 0.083 g plant/kg). These results revealed that the extract from leaves of Pimenta racemosa var. ozua exerts an important antinociceptive activity, associated to an anti-inflammatory effect which to appear be markedly influenced by the inhibition of neutrophil migration into inflamed tissue and that lack of toxic effects at usual doses.     

Analgesic, antiinflammatory and hypoglycaemic effects of ethanol extract of Zingiber officinale (Roscoe) rhizomes (Zingiberaceae) in mice and rats

The present study was undertaken to investigate the analgesic, antiinflammatory and hypoglycaemic effects of Zingiber officinale dried rhizomes ethanol extract (ZOE) in mice and rats. The analgesic effect of ZOE was evaluated by 'hot-plate' and 'acetic acid' analgesic test methods in mice; while the antiinflammatory and hypoglycaemic effects of the plant extract were investigated in rats, using fresh egg albumin-induced pedal oedema, and streptozotocin (STZ)-induced diabetes mellitus models. Morphine (MPN, 10 mg/kg), diclofenac (DIC, 100 mg/kg) and chlorpropamide (250 mg/kg) were used as reference drugs for comparison. ZOE (50-800 mg/kg i.p.) produced dose-dependent, significant (p < 0.05-0.001) analgesic effects against thermally and chemically induced nociceptive pain in mice. The plant extract (ZOE, 50-800 mg/kg p.o.) also significantly (p < 0.05-0.001) inhibited fresh egg albumin-induced acute inflammation, and caused dose-related, significant (p < 0.05-0.001) hypoglycaemia in normal (normoglycaemic) and diabetic rats. The findings of this experimental animal study indicate that Zingiber officinale rhizomes ethanol extract possesses analgesic, antiinflammatory and hypoglycaemic properties; and thus lend pharmacological support to folkloric, ethnomedical uses of ginger in the treatment and/or management of painful, arthritic inflammatory conditions, as well as in the management and/or control of type 2 diabetes mellitus in some rural Africa communities.     

落地生根的国内外研究进展△

目的：介绍落地生根的化学成分和药理作用研究进展,为进一步利用落地生根提供科学依据。方法：通过查阅近年的国内外文献,对落地生根进行了概述。结果：落地生根是一种价廉易得的中药材,为景天科落地生根属植物,其中含有大量丰富的化学成分,除具有观赏价值外,还具有广泛的药理作用,如抗炎镇痛作用,抗肿瘤作用,抑菌作用等,具有潜在的开发应用价值。课题组对落地生根作为外用药具有抗炎镇痛的作用进行研究,为落地生根的开发利用提供了新的方向。结论：落地生根具有较大的药用研究价值,特别是将其应用到抗炎镇痛方面。     

Anti-inflammatory, analgesic and anti-lymphocytic activities of the aqueous extract of Crinum giganteum

The anti-inflammatory, anti-lymphocytic and analgesic properties of Crinum giganteum, a popular herb used for the management of asthma and other respiratory disorders was investigated in rats and mice. The extract dose-dependently produced significant (P<0.05) inhibition of formalin induced pain in rats. It also demonstrated significant (P<0.01) inhibition of abdominal constriction induced with 0.75% v/v acetic acid in mice. On the cotton pellet induced granulomatous tissue formation in rats, the extract significantly (P<0.05) decreased the weight. However, no significant inhibition was observed in the egg albumin-induced inflammation in rats. Oral administration of this extract in rats for 14 days significantly affected (P<0.05) the total leukocyte count and the overall percentage lymphocytes. The intraperitoneal and per oral LD(50) were 627+/-5.8mg/kg and 1486+/-18.9 mg/kg in mice and 520+/-10.2mg/kg and 1023+/-4.3 mg/kg in rats, respectively. Preliminary phytochemical analysis of the extract indicates the presence of tannins. These results therefore indicate that C. giganteum bulb contains biologically active principles, which have potentials for the treatment of inflammatory processes.     

Analgesic and antiinflammatory effects of mollic acid glucoside, a 1 alpha-hydroxycycloartenoid saponin extractive from Combretum molle R. Br. ex G. Don (Combretaceae) leaf

The analgesic and antiinflammatory properties of mollic acid glucoside (MAG), a 1 alpha-hydroxycycloartenoid extract from Combretum molle leaf, have been investigated in mice and rats. The effects of graded doses of mollic acid glucoside (MAG, 5-80 mg/kg i.p.) were examined against thermally- and chemically-induced nociceptive pain in mice. Furthermore, the effects of graded doses of the plant extract (MAG, 5-80 mg/kg p.o.) were also investigated on rat paw oedema induced by subplantar injections of fresh egg albumin (0.5 mg/kg). Morphine (MPN, 10 mg/kg i.p.) and diclofenac (DIC, 100 mg/kg i.p.) were used as reference analgesic and antiinflammatory agents for comparison, respectively. Like DIC (100 mg/kg i.p.) and MPN (10 mg/kg i.p.), MAG (5-80 mg/kg i.p.) produced dose-dependent, significant (p < 0.05-0.001) analgesic effects against thermally and chemically induced nociceptive pain in mice. The extractive (MAG, 5-80 mg/kg i.p.) also significantly reduced (p < 0.05-0.001) rat paw oedema induced by subplantar injections of fresh egg albumin in a dose-related fashion. However, the extract (MAG, 5-80 mg/kg i.p.) was found to be less potent than diclofenac (DIC) as an analgesic or antiinflammatory agent. Experimental evidence obtained from this laboratory animal study indicates that the Combretum molle leaf extractive (MAG) possesses analgesic and antiinflammatory properties, and thus lend pharmacological credence to the folkloric, ethnomedical uses of the plant's leaf in the management, control and/or treatment of painful, arthritic and other inflammatory conditions in some rural communities of southern Africa.     

Analgesic and anti-inflammatory activity of Crinum glaucum aqueous extract.

The anti-inflammatory and analgesic effects of the aqueous extract of Crinum glaucum were evaluated in mice and rats using the carrageenan- and dextran-induced paw oedema, acetic acid-induced writhing, cold water tail flick and formalin pain tests. The extract (100-400 mg/kg) and acetylsalicylic acid (100 mg/kg) produced a significant (P<0.05) inhibition of the second phase response in the formalin pain model, while only the high dose (400 mg/kg) of the extract showed an antinociceptive effect in the first phase. The extract also showed a dose-dependent inhibition of acetic acid-induced abdominal writhes. The tail flick latency was dose dependently enhanced by the extract but this was significantly (P<0.05) lower than that produced by morphine (2 mg/kg). The extract (125-500 mg/kg) administered 1 h before or after carrageenan-induced paw swelling produced a dose dependent inhibition of the oedema. No effect was observed with the dextran-induced oedema model. The data obtained suggest that the anti-inflammatory and analgesic effects of the extract may be mediated via both peripheral and central mechanisms.     

Anti-nociceptive and anti-inflammatory activities of the methanolic extract of Parinari polyandra stem bark in rats and mice

The methanolic extract of the stem bark of Parinari polyandra (family Rosaceae) was investigated for possible anti-nociceptive and anti-inflammatory effects in mice and rats. Three models were used to study the extracts effects on nociception which were the acetic acid-induced abdominal constriction test, hot-plate method (both in mice) and the formalin test in rats. The anti-inflammatory effects were investigated employing the albumin-induced hind-paw oedema in rats. Results of the study revealed the extract to have significant (P<0.05) anti-nociceptive effect at a dose of 200 mg/kg p.o. in mice and rats in all the models for anti-nociception while 100 mg/kg p.o. showed significant (P<0.05) effect in the acetic acid-induced abdominal constriction test and in phase I of the formalin test. The extract also exhibited anti-inflammatory effects which were found to be significant (P<0.05) at 200 mg/kg p.o. in the rats tested. Preliminary phytochemical screening of the extract showed the presence of flavonoids, tannins, and saponin glycoside. The results suggest the extract contains pharmacologically active principles. The result is in agreement with the local application of the plant in painful and inflammatory conditions.     

Anti-inflammatory,analgesic activity and acute toxicity of Glaucium grandiflorum extract

The species of Glaucium have been used in Iranian herbal medicine as laxative, hypnotic, antidiabetic agents and also in the treatment of dermatitis. The anti-inflammatory and analgesic effects of the aerial parts of Glaucium grandiflorum Boiss & Huet (Papaveraceae), a native plant of Iran, were studied using carrageenan induced edema, formalin and hot plate tests. The G. grandiflorum extract at the dose of 200 mg/kg had more edema inhibition than indomethacin at the doses of 10 (P<0.01) and 8 mg/kg (P<0.001) in the carrageenan test. The ED₅₀ (i.p.) in the edema induced by carrageenan was 13.59 mg/kg. In formalin test, the extract (60–90 mg/kg, i.p.) caused graded inhibition of both phases of formalin-induced pain. In hot plate test, the i.p. administration of the extract at the doses of 60, 70, 80 and 90 mg/kg significantly raised the pain threshold at a observation time of 45 min in comparison with control (P<0.001). The extract, at the antinociceptive doses, did not affect motor coordination of animals when assessed in the rotarod model. The 72 h acute LD₅₀ value of this extract after i.p. administration in mice was 797.94 mg/kg.     

Antinociceptive and antiedematogenic effects of the aqueous extract of Hyptis pectinata leaves in experimental animals

The aqueous leaf extract of Hyptis pectinata (L.) Poit (Lamiaceae), popularly known in Brazil as "sambaicatá" or "canudinho", was tested for its antinociceptive effects using the abdominal writhing, hot plate and formalin test models, and for its aniedematogenic effects using the carrageenin and arachidonic acid-induced rat paw edema. The aqueous extract of Hyptis pectinata administered orally at doses of 100, 200 and 400 mg/kg had a significant antinociceptive effect in the test of acetic acid-induced abdominal writhing, with 43, 51 and 54% reduction of writhes, respectively, compared to the control. An increase in hot-plate latency of 47 and 37.5% was also observed in animals receiving doses of 200 and 400 mg/kg, p.o. when placed on a hot plate. In the formalin test, doses of 200 and 400 mg/kg, p.o. had no significant effect during the first phase of the test (0-5 min), while the dose of 200 mg/kg, p.o. reduced the nociceptive effect by 70% during the second phase (20-25 min). At the dose of 600 mg/kg, p.o., the aqueous extract inhibited carrageenin-induced rat paw edema by 34.1%, and the dose of 300 mg/kg administered intraperitoneally inhibited the rat paw edema induced by subplantar injection of arachidonic acid by 32.8%. These results suggest that the aqueous extract from the Hyptis pectinata leaves produces antiedematogenic and antinociceptive effects. The antinocipetion observed with the hot-plate test probably involves the participation of the opioid system.     

Antinociceptive and anti-inflammatory effects of Tanacetum parthenium L. extract in mice and rats

Oral administration of the feverfew (Tanacetum parthenium) extract led to significant antinociceptive and anti-inflammatory effects against acetic acid-induced writhing in mice and carrageenan-induced paw edema in rats, respectively. These responses were dose-dependent (10, 20, 40 mg/kg, p.o.). Parthenolide (1, 2 mg/kg i.p.), the active constituent of the extract also produced antinociceptive and anti-inflammatory effects. Naloxone (1 mg/kg i.p.), an opiate antagonist, failed to reverse feverfew extract and parthenolide-induced antinociception. Feverfew extract in higher doses (40, 60 mg/kg p.o.) neither altered the locomotor activity nor potentiated the pentobarbitone-induced sleep time in mice. It also did not change the rectal temperature in rats. Feverfew extract exerted antinociceptive and anti-inflammatory effects without altering the normal behaviour of the animals.     

Beneficial effects of Anadenanthera colubrina (Vell.) Brenan extract on the inflammatory and nociceptive responses in rodent models

Ethnopharmacological relevance

Anadenanthera colubrina (Vell.) Brenan, popularly known as “angico”, is a plant that has been widely used in folk medicine due to its anti-inflammatory property. To evaluate the pharmacological activities of this plant, studies were performed on its antinociceptive and anti-inflammatory properties.

Materials and methods

The AE of Anadenanthera colubrina, made from the bark, was used in rodents via oral route (p.o.), at 100, 200, and 400 mg/kg in classical models of nociception (acetic acid-induced writhing and hot-plate test) and inflammation evoked by carrageenan (e.g., paw edema, peritonitis, and synovitis).

Results

The acetic acid-induced abdominal writhes in mice were significantly reduced (P<0.001) by oral treatment with the extract (100, 200, and 400 mg/kg), but the extract did not significantly increase the latency in the nociceptive hot-plate test. Anadenanthera colubrina aqueous extract reduced significantly the edema and, besides, diminished the mieloperoxidase activity (200 and 400 mg/kg, P<0.01). The carrageenan-induced peritonitis was significantly reduced (P<0.05) by the aqueous extract at 100, 200, and 400 mg/kg. The aqueous extract (200 mg/kg) reduces the synovial leukocyte infiltration on carrageenan-induced synovitis in rats (P<0.01), but failed to significantly affect joint swelling and impaired mobility.

Conclusions

We show for the first time that the anti-inflammatory and peripheral antinociceptive activities of Anadenanthera colubrina are consistent, at least in part, with the use of this plant in popular medicine practices.     

Evaluation of the anti-inflammatory properties of Sclerocarya birrea (A. Rich.) Hochst. (family: Anacardiaceae) stem-bark extracts in rats

This study was designed to evaluate the anti-inflammatory effect of Sclerocarya birrea (family: Anacardiaceae) stem-bark aqueous and methanolic extracts in rats. Young adult, male Wistar rats (Rattus norvegicus) weighing 250-300g were used. The anti-inflammatory effects of aqueous and methanolic stem-bark extracts of the plant (SB, 500mg/kg p.o.) were examined on rat paw oedema induced by subplantar injections of fresh egg albumin (0.5ml/kg). Acetylsalicylic acid (ASA, 100mg/kg p.o.) was used as the reference anti-inflammatory agent for comparison. Both the aqueous and methanolic stem-bark extracts of S. birrea (SB, 500mg/kg p.o.) progressively and time-dependently reduced rat paw oedema induced by subplantar injections of fresh egg albumin. However, the methanolic extract of the plant produced relatively greater and more pronounced anti-inflammatory effect than its aqueous extract counterpart in the experimental animal model used. The two extracts of S. birrea stem-bark were found to be markedly less potent than ASA as anti-inflammatory agent. Although both the aqueous and methanolic extracts of S. birrea stem-bark are less potent than ASA as anti-inflammatory agent, the results of this experimental animal study indicate that the extracts possess anti-inflammatory activity, and thus lend credence to the suggested folkloric use of the plant in the management and/or control of arthritis and other inflammatory conditions in certain communities of South Africa.     

Evaluation of the antinociceptive effect of Rosmarinus officinalis L. using three different experimental models in rodents

The rationale of this investigation was to examine the antinociceptive effect of an ethanol extract of Rosmarinus officinalis (RO) aerial parts, using three different experimental models: acetic acid-induced writhing test and formalin test in mice; and a model of arthritic pain: “pain-induced functional impairment model in the rat (PIFIR model)”. The antinociceptive efficacies were evaluated using several dose–response curves and time courses. The antinociceptive effects from RO extract were compared with the antinociceptive effect of either tramadol (TR: 3.16–50 mg/kg, i.p. in mice, and 1.0–31.62 mg/kg, i.p. in rats) or acetylsalicylic acid (AA: 31.62–562.32 mg/kg, p.o.). RO extract (10–300 mg/kg, p.o.) significantly (P < 0.001) reduced the number of writhing movement induced by the i.p. administration of acetic acid solution in a dose-dependent way (ED₅₀ = 108.84 mg/kg, whereas, TR showed an ED₅₀ = 12.38 mg/kg). In addition, RO extract (30–300 mg/kg) significantly (P < 0.001) inhibited licking and shaking behaviours in both early (neurogenic pain) and in the late (inflammatory pain) phases of the formalin test. These effects were like those produced by TR. Concerning the results using the PIFIR model, RO extract (30–3000 mg/kg, p.o.) like either TR or AA, produced a significant (P < 0.001) and dose-dependent antinociceptive response in rats (RO: ED₅₀ = 222.78 mg/kg versus TR: ED₅₀ = 11.06 mg/kg and AA: ED₅₀ = 206.13 mg/kg). These results strongly suggest that aerial parts of RO possess antinociceptive and anti-inflammatory activity, and reinforce the use of this plant in folk medicine.