Analgesic and Antiinflammatory Effects of the Tannin Fraction from Myracrodruon urundeuva Fr. All.

The present work showed a significant antinociceptive activity in the tannin fraction (TF) extracted from the bark of Myracrodruon urundeuva Fr. All. This inhibitory effect was demonstrated not only against abdominal contractions but also in the formalin test in mice. In the first case, at doses of 0.1 and 1 mg/kg, i.p. the TF caused inhibitions of the order of 39.6% and 80.8%, respectively, and in the second one, inhibitions of 47.8% and 77.2% (phase I) and 59.2% and 100% (phase II), after the administration of 5 and 10 mg/kg, i.p. The antinociceptive effect was partially reverted by naloxone. The TF presented also an antioedematogenic effect in rat paw oedema induced by carrageenan as well as dextran. In the carrageenan model, significant inhibitions were seen at 2 h (29.7% and 41.7%) and 3 h (40.5% and 44.2%), after administration of 5 and 10 mg/kg, i.p. In the dextran induced oedema, the TF (10 mg/kg, p.o.) caused inhibitions of 29.2%, 42.4% and 54.5% at 2 h, 3 h and 4 h, respectively. The TF (10 and 25 mg/kg, i.p.) significantly inhibited the inflammatory events (vesical oedema and increased vascular permeability) which occur at the onset of the haemorrhagic cystitis induced by cyclophosphamide. After subcutaneous or oral administration, the TF (5–50 mg/kg) also blocked neutrophil migration induced by direct (fMLP) as well as indirect (carrageenan) stimuli. © 1997 by John Wiley & Sons, Ltd.     

Anti-inflammatory activity of Trichodesma indicum root extract in experimental animals

The chloroform extract of Trichodesma indicum root has been evaluated for anti-inflammatory activity against oedema produced by carrageenan, dextran, histamine and serotonin, and against formation of granulation tissues by cotton pellet in rats. The effect was compared with the activity of indomethacin, cyperoheptadine and dexamethasone against different types of inflammation. The chloroform extract at doses of 50, 100 and 200 mg/kg exhibited significant (P < 0.001) anti-inflammatory activity in acute and chronic inflammatory models. At 200 mg/kg the chloroform extract showed maximum inhibition of 48.12% in carrageenan-induced rat paw oedema while the standard indomethacin inhibited it by 54.32% after 3 h of carrageenan injection. The chloroform extract (50, 100 and 200 mg/kg) significantly (P < 0.001) and dose-dependently inhibited dextran, histamine and serotonin-induced rat paw oedema compared with control group (vehicle-treated). In the chronic inflammatory model, the chloroform extract (100 and 200 mg/kg) inhibited the granuloma weight by 15.42 and 21.12%, respectively, whereas the indomethacin and dexamethasone inhibited it by 29.29 and 34.13%, respectively. The results obtained suggest marked anti-inflammatory activity of the extract at the dose levels examined.     

Analgesic and anti-inflammatory activities of the crude hydroalcoholic extract obtained from the bark of Hymenaea martiana

Experiments were designed to examine the analgesic and anti-inflammatory activities of the crude hydroalcoholic extract (CE) of Hymenaea martiana. The CE of H. martiana (25-200 mg/kg, i.p.) caused a graded inhibition of hindpaw oedema induced by carrageenan, PAF-acether (PAF), serotonin (5-HT), dextran and histamine (HIS). However, the CE given orally up to 500 mg/kg had no effect on the agonist-induced hindpaw oedema. The CE given intraperitoneally, but not orally, caused a graded and pronounced inhibition of His, 5-HT, bradykinin (BK) and PAF-induced increase of vascular permeability. When the CE was given orally (300 mg/kg) once a day for 15 days it caused a significant increase of agonist-induced increase of vascular permeability. The CE given either by p.o. or by i.p. routes (100-800 mg/kg) dose-dependently inhibited arachidonic acid (AA)-induced ear oedema in mice, being significantly more potent when it was given by the latter route. In contrast, CE at the same doses, failed to inhibit croton-oil-induced ear oedema in mice. The CE of H. martiana given by either i.p. or p.o. routes caused a marked and dose-dependent antinociceptive activity as revealed by its antagonistic action against acetylcholine, acetic acid or AA-induced writhing responses in mice, being more effective when given intraperitoneally. These results, and those previously reported with the CE of H. martiana in the isolated preparations, provide strong experimental support which argues in favour of the beneficial use of this plant extract in folk medicine. The exact mechanism that underlies its analgesic and anti-inflammatory profiles remains unclear, but may result from its ability to inhibit the generation of lipoxygenase and/or cyclooxygenase products of the arachidonic acid pathway.     

Analgesic and anticonvulsant effects of extracts from the leaves of Kalanchoe crenata (Andrews) Haworth (Crassulaceae)

Kalanchoe crenata Andr. (Crassulaceae) is a fleshy herbaceous plant used in the African traditional medicine as remedies against otitis, headache, inflammations, convulsions and general debility. In the present work, the analgesic effects of methylene chloride/methanol (1:1) (CH(2)Cl(2)/CH(3)OH) extract and its hexane, methylene chloride (CH(2)Cl(2)), ethyl acetate, n-butanol fractions and aqueous residue have been evaluated using acetic acid, formalin and pressure test. The anticonvulsant effects of the CH(2)Cl(2)/CH(3)OH extract were also investigated on seizures induced by pentylenetetrazol (PTZ 70 mg/kg), strychnine sulphate (STN 2.5 mg/kg) and thiosemicarbazide (TSC 50 mg/kg). CH(2)Cl(2)/CH(3)OH extract and its fractions, administered orally at the doses of 150 and 300 mg/kg, exhibited protective effect of at least 30% on the pain induced by acetic acid. The CH(2)Cl(2) fraction at 300 mg/kg showed a maximal effect of 78.49%. The CH(2)Cl(2)/CH(3)OH extract and its CH(2)Cl(2) fraction at the doses of 150 and 300 mg/kg significantly reduced the first phase of pain induced by formalin while the second phase was completely inhibited. The CH(2)Cl(2) fraction produced more than 45% reduction in the sensitivity to pain induced by pressure. The CH(2)Cl(2)/CH(3)OH extract of Kalanchoe crenata significantly increased the latency period in seizures induced by PTZ and significantly reduced the duration of seizures induced by the three convulsant agents. The extract protected 20% of animals against death in seizures induced by TSC and STN. These results suggest a peripheral and central analgesic activities as well as an anticonvulsant effect of the leaves of Kalanchoe crenata.     

Anti-inflammatory and antinociceptive activities of extract, fractions and populnoic acid from bark wood of Austroplenckia populnea

Austroplenckia populnea (Reiss) Lund is a Brazilian plant from "cerrado", which belongs to Celastraceae family, popularity know as "marmelinho-do campo, mangabeira-brava, mangabarana, vime and maria-mole". This plant is used in folk medicine to treat dysenteries and inflammatory disorders, such as rheumatism. Austroplenckia populnea bark hydroalcoholic crude extract, and its hexane, chloroform and ethyl acetate fractions, obtained by partition, as well as the isolated populnoic acid were investigated for their anti-inflammatory (carrageenan, dextran and histamine-induced rat paw oedema, histamine-induced increase in vascular permeability, and granulomatous tissue induction) and analgesic activities (writhing and hot plate tests). The ED(50) (oral) of the crude extract for the inhibition of carragenan-induced rat paw oedema assay was determined to be 200 mg/kg, which was also used in the assays with the extract and its fractions in all other experiments. Populnoic acid was administered in the dose of 50 mg/kg. Crude extract, hexane and chloroform fractions (200 mg/kg), and indomethacin (10 mg/kg) inhibited significantly (p<0.05) the formation of the carrageenan-induced rat paw oedema, measured in third hour of experiment (peak of oedema formation) by 43.2%, 37.3%, 31.1% and 59.3%, respectively. There was a significant reduction (p<0.05) in dextran-induced rat paw oedema in all groups, while in the assay using histamine as the oedematogenic agent, only the groups treated with populnoic acid (50 mg/kg) and cyproheptadine (10 mg/kg) displayed significant reduction (p<0.05). The populnoic acid and cyproheptadine reduced the peak of oedema formation (1st hour) by 41.3% and 34.7%, respectively. Only for the groups treated with populnoic acid (50 mg/kg) and cyproheptadine (10 mg/kg) it was observed a significant (p<0.05) reduction in histamine-induced increase in vascular permeability (44.8% and 80.3%, respectively). Granulomatous tissue formation was significantly inhibited (p<0.05) by both hexane fraction (46.0%) and dexamethasone (66.2%). In the analgesic assays, the crude extract and its hexane and chloroform fractions, as well as indomethacin diminished significantly the number of writhings (p<0.05) by 69.6%, 47.2%, 44.8% and 62.8%, respectively. On the other hand, none assayed sample displayed significant result in the hot plate test. Based on the obtained results it is suggested that extracts of Austroplenckia populnea bark and populnoic acid display anti-inflammatory activity, supporting its folkloric use to treat inflammatory disorders.     

Anti-inflammatory, analgesic and antipyretic effects of methanol extract from Bauhinia racemosa stem bark in animal models

In this study, the anti-inflammatory, analgesic, and antipyretic effects of 50, 100 and 200 mg/kg body weight of methanol extract obtained from Bauhinia racemosa stem bark, the so-called MEBR, were investigated. The effects of MEBR on the acute and chronic phases of inflammation were studied in carrageenan, dextran and mediators (histamine and serotonin)-induced paw oedema and cotton pellet-induced granuloma, respectively. Analgesic effect of MEBR was evaluated in acetic acid-induced writhing and hotplate tests. Antipyretic activity of MEBR was evaluated by yeast-induced hyperpyrexia in rats. The anti-oedema effect of MEBR was compared with 10 mg/kg of indomethacin orally. In acute phase of inflammation, a maximum inhibition of 44.9, 43.2, 44.8 and 45.9% (P<0.001) was noted at the dose of 200 mg/kg b.w. after 3h of treatment with MEBR in carrageenan, dextran, histamine and serotonin-induced paw oedema, respectively. Administration of MEBR (200 mg/kg b.w.) and indomethacin (10 mg/kg b.w.) significantly (P<0.05) decreased the formation of granuloma tissue induced by cotton pellet method at a rate of 50.4 and 56.2%, respectively. The extract also inhibited peritoneal leukocyte migration in mice. The MEBR also produced significant (P<0.01) analgesic activity in both models. Further, the MEBR potentiated the morphine- and aspirin-induced analgesic in mice. Treatment with MEBR showed a significant (P<0.01) dose-dependent reduction in pyrexia in rats. The results suggest that MEBR possess potent anti-inflammatory, analgesic and antipyretic activity.     

Anti-inflammatory and anti-allergic properties of the essential oil and active compounds from Cordia verbenacea

The anti-inflammatory and anti-allergic effects of the essential oil of Cordia verbenacea (Boraginaceae) and some of its active compounds were evaluated. Systemic treatment with the essential oil of Cordia verbenacea (300-600mg/kg, p.o.) reduced carrageenan-induced rat paw oedema, myeloperoxidase activity and the mouse oedema elicited by carrageenan, bradykinin, substance P, histamine and platelet-activating factor. It also prevented carrageenan-evoked exudation and the neutrophil influx to the rat pleura and the neutrophil migration into carrageenan-stimulated mouse air pouches. Moreover, Cordia verbenacea oil inhibited the oedema caused by Apis mellifera venom or ovalbumin in sensitized rats and ovalbumin-evoked allergic pleurisy. The essential oil significantly decreased TNFalpha, without affecting IL-1beta production, in carrageenan-injected rat paws. Neither the PGE(2) formation after intrapleural injection of carrageenan nor the COX-1 or COX-2 activities in vitro were affected by the essential oil. Of high interest, the paw edema induced by carrageenan in mice was markedly inhibited by both sesquiterpenic compounds obtained from the essential oil: alpha-humulene and trans-caryophyllene (50mg/kg, p.o.). Collectively, the present results showed marked anti-inflammatory effects for the essential oil of Cordia verbenacea and some active compounds, probably by interfering with TNFalpha production. Cordia verbenacea essential oil or its constituents might represent new therapeutic options for the treatment of inflammatory diseases.     

Antihyperalgesic and Antiedematous Activities of Bisabolol‐Oxides‐Rich Matricaria Oil in a Rat Model of Inflammation

From the dried flower heads of Matricaria recutita L., essential oil was isolated by hydrodistillation, and in the obtained blue oil, α‐bisabolol oxide A (21.5%), α‐bisabolol oxide B (25.5%) and (Z)‐spiroether (cis‐en‐yn‐spiroether) (10.3%) were identified as the main compounds, by gas chromatography (GC) and GC–mass spectrometry analyses. The antihyperalgesic effects of this oil were examined in a rat model of inflammation induced by carrageenan, through a modified ‘paw‐pressure’ test. Antiedematous effects were examined in a rat model of inflammation induced by carrageenan, dextran and histamine, through plethysmometry. Matricaria oil (25, 50 and 100 mg/kg, p.o.) exhibited a significant dose‐dependent reduction of hyperalgesia and edema induced by carrageenan in both prophylactic and therapeutic treatment schemes. It was more efficacious in the prophylactic treatment scheme, and the corresponding median effective dose (ED₅₀) ± standard error of the mean (SEM) values were 49.8 ± 6.0 and 42.4 ± 0.2 mg/kg for antihyperalgesic and antiedematous effects, respectively. Prophylactic treatments with matricaria oil (25, 50 and 100 mg/kg, p.o.) caused a significant dose‐dependent antiedematous effect in dextran‐induced edema with lower efficacy than in the carrageenan model. In a dose of 100 mg/kg, p.o., matricaria oil caused a slight reduction of histamine‐induced edema. These results suggest that bisabolol‐oxide‐rich matricaria oil may be effective against pain and edema present in various inflammatory conditions, which supports matricaria traditional uses. Copyright © 2013 John Wiley & Sons, Ltd.     

Evaluation of pharmacological activity of a crude hydroalcoholic extract from Jatropha elliptica

The pharmacological effect of the hydroalcoholic extract of Jatropha elliptica was analysed in in vivo and in vitro models. When given orally in mice, the extract showed a low acute toxicity (LD₅₀ 5 g/kg). In a dose of 0.5 or 1 g/kg p.o. the extract did not interfere with diuresis in the rat, but was found to be effective in blocking rat paw oedema induced by carrageenan and partially, serotonin-induced oedema. In the same dose, the extract failed to inhibit rat paw oedema induced by dextran and the increase of rat cutaneous vascular permeability caused by Bothrops Jararaca venom, dextran, histamine, PAF-acether and serotonin. Pre-incubation of the isolated rat uterus and guinea-pig ileum with the extract (0.2–0.8 mg/mL), produced a concentration-related and non-competitive inhibition of contractions induced by acetylcholine and bradykinin. However, the extract was about 2-fold more potent in inhibiting the contraction of both agonists in guinea-pig ileum than in rat uterine muscle. In rat aorta, the extract (50–100 μg/mL) caused a concentration-dependent inhibition of noradrenaline-evoked contractions, being about 5-fold more potent when compared to the IC₅₀ values obtained in rat uterus.     

Anti-inflammatory and smooth muscle relaxant activities of the hydroalcoholic extract and chemical constituents from Amburana cearensis A C Smith

Amburana cearensis A. C. Smith, Fagaceae, is a medicinal plant commonly known as 'cumaru' and used in Northeast Brazil for the treatment of respiratory tract diseases. In the present work, we investigated the anti-inflammatory and smooth muscle relaxant activities of the hydroalcoholic extract (HAE), coumarin (Coum) and fl avonoid fraction (FF) isolated from the trunk barks of Amburana cearensis A. C. Smith. It was shown that HAE (200 and 400 mg/kg), Coum (20 and 40 mg/kg) and FF (40 mg/kg), administered orally, significantly inhibited both leukocyte and neutrophil migrations, in the carrageenan or N-formyl-methyl-leucyl-phenylalanine (fMLP)-induced migration in rat peritoneal cavity. The increase in cutaneous vascular permeability induced by serotonin in rats was significantly blocked by HAE (150 mg/kg, i.p.), Coum (5 mg/kg, i.p.) and FF (20 mg/kg, i.p.). However, only HAE blocked the histamine effect on Evans blue extravasation. In the guinea-pig trachea precontracted with carbachol (0.3 microM), histamine (0.1 microM) or KCl (0.1 M), the HAE, Coum and FF evoked a concentration-dependent relaxation in the presence of the three agonists. HAE (100-800 microg/ml) and Coum (4-32 microg/ml) also caused significant relaxation of the rat vas deferens previously contracted with adrenaline, acetylcholine or barium chloride. In addition, HAE, Coum and FF inhibited the histamine and serotonin-induced increase of cutaneous vascular permeability in rats.     

Analgesic and antiinflammatory activities of Ageratum conyzoides in rats

The water soluble fraction (WSF) obtained from a hydroalcohol extract of A. conyzoides, a medicinal plant used in Brazilian folk medicine, was evaluated for possible analgesic and antiinflammatory activities. It was demonstrated that WSF (20–50 mg/kg; i.p.) treatment reduced the articular incapacitation induced by carrageenin (300 μg) in rats. In this model, naloxone (2 mg/kg) blocked the analgesic action of morphine (2 mg/kg) but did not change the WSF antinociceptive effect. It suggests that endogenous opioids are not involved in the WSF antinociceptive effect. The neutrophil migration induced by carrageenin (300 μg) injection into rat peritoneal cavities and into 6-day-old subcutaneous air-pouches was significantly inhibited (p <0.05) by WSF pre-treatment (30 and 50 mg/kg; s.c.). At the same dose WSF also inhibited (p <0.05) the carrageenin (400 μg/paw)-induced oedema, but failed to modify the oedema induced by dextran (100 μg/paw). Furthermore, the increase in the cutaneous vascular permeability induced by the potent leukocyte chemotactic agent LTB₄ (39 ng co-injected with 500 ng iloprost, i.d.) was significantly blocked by WSF (30 mg/kg; i.p.). However, in the same dose WSF caused a 2-fold increase in the vascular permeability induced by histamine (10 μg), a direct vasoactive mediator. These results suggest that WSF can inhibit the inflammatory reactions induced by neutrophil mobilizing stimuli. © 1997 John Wiley & Sons, Ltd.     

Studies on antiinflammatory effect of Cassia tora leaf extract (fam. Leguminosae)

The antiinflammatory effect of the methanol extract of the leaves of Cassia tora was investigated against carrageenin, histamine, serotonin and dextran-induced rat hind paw oedema. It exhibited significant antiinflammatory activity against all these agents. The extract (400 mg/kg) showed maximum inhibition of oedema of 40.33%, 31.37%, 53.57% and 29.15% at the end of 3 h with carrageenin, dextran, histamine and serotonin-induced rat paw oedema, respectively. Using a chronic test, the granuloma pouch in rats, the extract exhibited a 48.13% reduction in granuloma weight. © 1998 John Wiley & Sons, Ltd.     

Anti-inflammatory and analgesic properties of water-ethanolic extract from Pothomorphe umbellata (Piperaceae) aerial parts

Anti-inflammatory and analgesic activities as well as the median lethal dose (LD50) of water-ethanolic extract (PHE) of the aerial parts of Pothomorphe umbellata were evaluated in animal models. The ED(50) (oral) for the inhibition of carrageenan-induced rat paw edema assay was determined to be 550 mg/kg, while the LD(50) was higher than 2.0 g/kg. At a dose of 550 mg/kg, PHE inhibited the inflammatory process by 48.7% (P < 0.05) on the third hour of the assay (edema peak) when compared to the untreated control. Indomethacin, the positive control used in this test, inhibited the edema by 58.6% at a dose of 10 mg/kg, when compared to the untreated control (P < 0.05). All three fractions--hexane, methylene chloride and ethyl acetate--obtained by partition of PHE with respective solvents also showed inhibition of the edema induced by carrageenan over a period of 4h but the methylene chloride fraction showed the best activity. The activity shown by the methylene chloride fraction at 200 mg/kg was comparable to that exhibited by indomethacin at a dose of 10mg/kg. The number of writhings induced by a 0.6% acetic acid solution intraperitoneal injection was decreased by 22% (P < 0.05) in the group treated orally with Pothomorphe umbellata crude extract. PHE also inhibited the granulomatous tissue formation in rats by 6.2% (P < 0.05). In the same assay, topically applied dexamethasone decreased the granuloma formation by 14.2%. The above results suggest that Pothomorphe umbellata crude extract has analgesic and anti-inflammatory properties supporting its folkloric use for the treatment of these conditions.     

Antinociceptive and anti-inflammatory effects of Satureja hortensis L. extracts and essential oil

Satureja hortensis L. (Lamiaceae) is a medicinal plant used in Iranian folk medicine as muscle and bone pain reliever. In the present study, hydroalcoholic extract, polyphenolic fraction and essential oil of the aerial parts of the herb were prepared and evaluated for the analgesic activity using light tail flick, formalin and acetic acid-induced writhing in mice. Also, the anti-inflammatory effects of the above-mentioned preparations were assessed using carrageenan-induced paw edema in rats. Results showed that in the light tail flick test neither the essential oil nor the extracts could exert any significant effect. The hydroalcoholic extract (2000 mg/kg, p.o.) and the essential oil (200 mg/kg, p.o.) inhibited the mice writhing responses caused by acetic acid. In formalin test, hydroalcoholic extract (500-2000 mg/kg, p.o.), polyphenolic fraction (250-1000 mg/kg, p.o.) and the essential oil (50-200 mg/kg, p.o.) showed analgesic activity and pretreatment with naloxone (1 mg/kg, i.p.) or caffeine (20 mg/kg, i.p.) failed to reverse this antinociceptive activity. Polyphenolic fraction (1000 mg/kg, p.o.) and the essential oil (200 mg/kg) reduced edema caused by carrageenan. These results suggest that S. hortensis L. has antinociceptive and anti-inflammatory effects and probably mechanism(s) other than involvement of opioid and adenosine receptors mediate(s) the antinociception.     

Antiinflammatory and antinociceptive activities of Blechnum occidentale L. extract

Aim of study

Blechnum occidentale L. is a terrestrial fern that ranges from the United States to South America, and is employed in Brazilian folk medicine. In the present study we investigated the antinociceptive and antiinflammatory activities of the methanolic extract of Blechnum occidentale L. (MEB) in animal models of pain and inflammation to support its medicinal use in treatment of inflammatory and pulmonary diseases, urinary infections and liver diseases.

Materials and methods

The antinociceptive activity of MEB was evaluated using the writhing, formalin, and tail flick tests. The antiinflammatory activity of MEB was evaluated in carrageenan-induced paw oedema and neutrophil migration. In order to discard possible non-specific muscle relaxant or sedative effects of MEB, mice motor performance was evaluated in the rota rod test and its toxicity evaluated over 14 days.

Results

Intraperitoneal (IP) administration of MEB (0.01–100 mg/kg) produced a dose-related antinociception on acetic acid-induced writhing in mice. Oral administration of MEB, at a different range of doses (100–400 mg/kg), also produced significant antinociceptive effect on the writhing test. Furthermore, treatment with MEB (100 and 200 mg/kg IP) inhibited significantly both the early and late phases of formalin-induced hypernociception in rats. In contrast, treatment with MEB (100 and 200 mg/kg IP) did not prevent the thermal nociception in the tail flick test. The IP administration of MEB (100 and 300 mg/kg) significantly reduced the paw oedema induced by carrageenan. Moreover, systemic treatment with MEB (11–300 mg/kg) reduced the neutrophil migration in the carrageenan-induced migration to the peritoneal cavity. In the rota rod test, MEB-treated mice did not show any significant motor performance alterations with the dose of 300 mg/kg. In addition, over the study duration of 14 days, there were no deaths or toxic signs recorded in the mice given 100 or 1000 mg/kg of MEB.

Conclusion

The results described here are the first report of pharmacological studies of Blechnum occidentale L. and indicate that this plant has antinociceptive and antiinflammatory activities which support its folk medicine use.     

Evaluation of antinociceptive and antiinflammatory activities of the essential oil (EO) of Ocimum micranthum Willd. from Northeastern Brazil

The EO of Ocimum micranthum was studied for a possible analgesic effect on the acetic acid induced writhing and formalin test in mice and antioedema activities on the carrageenan and dextran induced paw oedema in rats. The EO demonstrated antinociceptive effects, and pretreatment with naloxone did not reverse the antinociception, indicating that the opioid system is not involved. On the other hand, pretreatment with L-arginine (L-arg) reversed the antinociception, suggesting involvement of the nitric oxide (NO) system. The EO did not present an antioedematogenic effect in the carrageenan and dextran models.     

Antinociceptive activity of Syzygium jambos leaves extract on rats

Syzygium jambos (L.) Alston (Myrtaceae) (syn Eugenia jambos) is a widespread medicinal plant traditionally used in sub-Saharan Africa to treat several diseases. The analgesic potential of leaf hydro-alcoholic extracts was assessed in rats. Hot plate and formalin tests were used to estimate cutaneous nociception whereas measurements of forelimb grip force were done to assess muscular nociception under normal and inflammatory conditions. In the hot plate test, Syzygium jambos extract produced a significant increase in the withdrawal response latencies in a dose-dependant manner (10-300 mg/kg i.p.) and with a maximal effect (analgesic efficacy) similar to that of morphine. The extract (100-300 mg/kg i.p.) significantly reduced pain scores in all the phases of the formalin test with an analgesic efficacy higher than that shown by diclofenac. Although the extract (300 mg/kg) did not alter grip force in intact rats, it reversed the reduction in grip force induced by bilateral injection carrageenan in the forelimb triceps. This analgesic effect of the extract on muscle hyperalgesia was not antagonized, but enhanced, by naloxone. Thus, the Syzygium jambos extract has remarkable analgesic effects on both cutaneous and deep muscle pain that is not mediated by opioid receptors.     

Anti-inflammatory activity of Markhamia tomentosa (Benth.) K. Schum. Ex Engl. ethanolic leaf extract

Ethnopharmacological relevance

The leaves of Markhamia tomentosa (Benth.) K. Schum (Bignoniaceae) are used traditionally for the treatment of oedema and rheumatoid arthritis in Nigeria.

Aim of the study

The aim of the work was to investigate the anti-inflammatory activity of the ethanolic leaf extract of Markhamia tomentosa.

Materials and methods

The extract was screened using the carrageenan-induced paw oedema in rats, xylene-induced oedema in mice and the formalin-induced oedema in mice at 50, 100, 200 mg/kg doses p.o respectively. The mechanism by which the extract mediated the anti-inflammatory activity was assessed using the histamine-induced rat paw oedema and serotonin-induced rat paw oedema at the highest dose (200 mg/kg).

Results

The results showed that the extract produced a significant dose-dependent inhibition in carrageenan-induced, xylene-induced and the formalin tests. The extract exerted a significant inhibition of 54.55% (P<0.0001) and 42.11% (P<0.01) at 90 min in the histamine-induced and serotonin-induced rat paw oedema models respectively.

Conclusions

These findings suggest that the ethanolic leaf extract of Markhamia tomentosa possesses anti-inflammatory activity possibly mediated by histamine. The results justify the use of the plant in the preparation of ethno medicines used in the treatment of ailments associated with inflammation.     

Polysaccharide fractions of Caesalpinia ferrea pods: potential anti-inflammatory usage

Ethnopharmacological relevance

Caesalpinia ferrea (Caesalpinioideae), known as pau-ferro or juca, has been used in the traditional medicine in North and Northeast of Brazil in inflammatory disorder, among others. Thus, experimental evaluation of the anti-inflammatory activity of extracts and fraction polysaccharides of Caesalpinia ferrea pods, and correlation with its anti-inflammatory activity and popular use is important.

Materials and methods

Total polysaccharides (TPL) were applied to ion exchange chromatography and eluted stepwise. Paw edema was induced s.c. by λ-carrageenan, dextran, histamine, serotonin, compound 48/80, bradykinin, prostaglandin E₂ (PGE₂) or l-arginine and analyzed by plethysmometry and protein leakage by spectrophotometry. Peritonitis was induced i.p. by carrageenan or N-formyl-methionyl-leucyl-phenylalanine (fMLP) and analyzed 4 h later for leukocyte migration and protein leakage. Animals were treated i.v. with TPL or polysaccharide fractions (0.01, 0.1, 1 mg/kg) 30 min before stimuli in both models. Toxicity (variation of body/organ mass and hematological/biochemical parameters) was evaluated after the seven-day treatment with the most active polysaccharide fraction (1 mg/kg; i.v.).

Results

Chromatography of TPL (2.8% yield) provided three major polysaccharide fractions (FI, FII, FIII). At 1 mg/kg, TPL inhibited the paw edema induced by carrageenan (60%) and FIII (fraction presenting high carbohydrate and low protein content) inhibited the inflammatory parameters in the paw edema induced by the following stimuli: carrageenan (70%), dextran (53%), histamine (65%), serotonin (62%), bradykinin (60%), PGE₂ (63%), nitric oxide (61%) and compound 48/80 (36%). Additionally, FIII at 1 mg/kg inhibited the carrageenan-induced edema in animals with intact mast cells, but only the late phase of those with degranulated mast cells elicited by compound 48/80. Moreover, FIII inhibited cell migration and protein leakage in the model of peritonitis elicited by carrageenan (88%) and fMLP (64%), being well tolerated by animals.

Conclusions

Extracts and polysaccharide fractions of Caesalpinia ferrea pods exhibit potent anti-inflammatory activity via negative modulation of histamine, serotonin, bradykinin, PGE₂ and NO released in the carrageenan-induced edema, showing involvement of mast cells. FIII could be interfering not only in the vascular, but also in cellular inflammatory events, revealing to be an important active component of traditionally prepared remedies used to treat inflammatory states.     

Antihypertensive and antioxidant effects of Allanblackia floribunda Oliv. (Clusiaceae) aqueous extract in alcohol- and sucrose-induced hypertensive rats

Aim of the study

Allanblackia floribunda Oliv. (Clusiaceae), an evergreen tree of the rain-forest has long been used in traditional African medicine to treat hypertension. The aim of this study was to evaluate the protective effect of Allanblackia floribunda aqueous extract on alcohol- and sugar-induced hypertension in rats.

Material and methods

Alcohol-induced hypertensive rats (AHR) were obtained by oral administration of ethanol (3 g/kg/day) while sucrose (5, 6 and 7% in drinking water) was used for sucrose-induced hypertensive rat (SuHR). Both models of animals concomitantly received either aqueous extract (200 or 400 mg/kg; p.o.) or nifedipine (10 mg/kg; p.o.) all along the 8 weeks of experiment. Blood pressure and heart rate were measured using the direct cannulation method. The effects of the plant extract on lipid profile, oxidative stress markers, as well as on kidney and liver functions were evaluated at the end of the treatment by the colorimetric method.

Results

At the doses of Allanblackia floribunda (200 and 400 mg/kg/day) significantly prevented (21.74; 26.65% and 11.71; 24.58% of reduction) the increase in mean blood pressure on AHR and SuHR, respectively. Administration of the plant extract at the dose of 400 mg/kg led to the prevention of total cholesterol (42.82%), HDL-cholesterol (36.59%) and triglycerides (9.67%) increase in serum lipid in AHR as compared to the untreated AHR. In SuHR, the extract significantly prevented the high concentrations of total cholesterol (44.08%) and triglycerides (33.05%) induced by sucrose treatment as compared to the untreated SuHR, without affecting that of HDL-cholesterol. Allanblackia floribunda (200 and 400 mg/kg) also prevented the increase in atherogenic index by 54.45 and 42.94% in AHR and by 23.70 and 44.32% in SuHR, respectively. Allanblackia floribunda (400 mg/kg) prevented the increase in bilirubine (19.59 and 16.56%), urea (33.36 and 28.2%), ALT (29.55 and 33.09%) and AST (36.28 and 37.12%) of AHR and SuHR, respectively. Treatment with plant extract significantly prevented the increase of superoxide dismutase (SOD), malondialdehyde (MDA) and catalase and the decrease of reduced glutathione (GSH) concentration in aorta, heart, kidney and liver of AHR and SuHR.

Conclusion

These results demonstrate that the aqueous extract of Allanblackia floribunda can prevent alcohol- and sugar-induced hypertension and oxidative stress in rats. These findings could therefore justify its use in traditional medicine.