Studies on the anti-inflammatory and related pharmacological properties of the aqueous extract of Bridelia ferruginea stem bark

The anti-inflammatory profile of the aqueous extract of Bridelia ferruginea stem bark was investigated using both in vivo and in vitro models. The extract exhibited strong topical anti-inflammatory effect shown as inhibition of croton oil-induced ear oedema in mice, and reduced hind-paw swelling and growth retardation in the adjuvant-induced arthritis model in rats, following oral administration at 10, 20, 40 or 80 mg/kg. The extract (10-80 mg/kg, p.o.) caused an inhibition of increase in vascular permeability in both cyclophosphamide-induced haemorrhagic cystitis and acetic acid-induced vascular permeability in rats and mice, respectively. B. ferruginea produced stabilization of erythrocytes exposed to heat and stress-induced lysis. Antipyretic and analgesic properties of the extract were also observed.     

Effects of the aqueous extract of Bridelia ferruginea stem bark on carrageenan-induced oedema and granuloma tissue formation in rats and mice.

The anti-inflammatory activity of the aqueous extract of the stem bark of Bridelia ferruginea was evaluated using carrageenan-induced paw oedema in rats and mice, and the cotton pellet granuloma method. The extract at doses ranging from 10 to 80 mg/kg p.o. significantly inhibited the carrageenan-induced rat paw oedema, with an ID50 value of 36 mg/kg. However, a low activity was produced in the mouse paw oedema. The extract also suppressed the granulomatous tissue formation of chronic inflammation. B. ferruginea therefore proved to be effective in both the acute and chronic phases of the inflammatory process.     

Anti-inflammatory properties of phenolic lactones isolated from Caesalpinia paraguariensis stem bark

Ethnopharmacological relevance

Caesalpinia paraguariensis (D. Parodi) Burkart stem bark infusion (CPBI) is traditionally used in Argentina because their “vulnerary” properties.

Aim of the study

CPBI was studied throughout bio-guided purification procedures conducted by in vitro biological assays in order to isolate the main bioactive compounds.

Material and methods

Anti-inflammatory activity was assessed by enzyme inhibition assays of Hyaluronidase (Hyal) and inducible Nitric Oxide Synthase (iNOS). The antioxidant properties were evaluated by DPPH free radical scavenging assay, lipid peroxidation inhibition assay on erythrocyte membranes, and a cell-based assay that included the fluorescent probe (DCFH-DA) for indicating reactive oxygen species (ROS) generation. Bioactive compounds were purified by chromatographic methods and their structures elucidated using spectroscopic methods (ESI-MS and 1D/2D-¹H/¹³C-NMR).

Results

Four main bioactive compounds were isolated from CPBI: ellagic acid (1), 3-O-methylellagic acid (2), 3,3'-di-O-methylellagic acid (3) and 3,3'-di-O-methylellagic-4-β-D-xylopyranoside (4). These were bioactive at concentrations in which are present in CPBI, being compounds 2 and 3 the best enzyme inhibitors of Hyal and iNOS, reaching the 90% inhibitory concentration (IC₉₀) values ranging from 2.8 to 16.4 μM, that are better than that of the positive controls, aspirin (IC₉₀: no reached) and aminoguanidine (IC₉₀: 20.2 μM) respectively. Compounds 2 and 3 were also better scavengers for lipoperoxides than butylated hydroxytoluene (BHT), reaching the 90% effective concentration (EC₉₀) at 1.2–4.5 μg/ml, and for DPPH radical (2.5–7.3 μg/ml); moreover compounds were able to exert its scavenging action on intracellular ROS. Structural features relevant to the biological activities are discussed.

Conclusions

This work provides scientific validity to the popular usage of CPBI.     

Effects of stembark and leaf extracts of Bridelia ferruginea on skeletal muscle

The ethanolic extracts of the leaves and stembark of Bridelia ferruginea were separately investigated for their effects on skeletal muscle using the phrenic nerve-hemidiaphragm muscle preparation from rats. The bark extract inhibited twitch tension induced by direct electrical stimulation (muscle) (MS) but not indirect electrical stimulation (nerve) (NS) of the diaphragm. It inhibited tetanus tension to both nerve (TNS) and muscle stimulation (TMS), had no effect on K⁺-induced contracture and reduced the minimal fusion frequency (MFF). The leaf extract had no effect on twitch tension to NS and MS or K⁺-induced contracture but increased tetanus tension to TNS or TMS as well as MFF. These findings suggest that the bark extract does not affect influx of extracellular Ca²⁺ but inhibits the intracellular mobilization of Ca²⁺. The leaf extract also had no effect on influx of extracellular Ca²⁺ but most likely facilitated the intracellular mobilization of Ca²⁺. Thus, the intracellular action of the bark extract is opposite to that of the leaf extract.     

Solution and Colour Stability of the Bark Extract of Bridelia ferruginea Benth

A solvent system consisting of water: propylene glycol: ethanol (2:2:1) was found suitable for diluting the ethanol bark extract and for reconstituting the freeze-dried extract of Bridelia ferruginea Benth for preparation of a gargle formulation. Such solutions remained clear when subjected to high storage temperatures and eight freeze-thaw cycles. The wine colour of Bridelia bark extract solution darkened on storage. Darkening was accelerated by heat while light had minimal effect. Inclusion of certain antioxidants—sodium metabisulphite, ascorbic acid and citric acid, reduced the colour change. Heating the freeze-dried extract at 115°C for 4 h and at 130°C for at least 1 h arrested the colour change. When lime juice was added to the solution of the heated powder, the colour of the resulting solution became unstable implicating a pH effect on colour stability. The colour of bottle and use of carton for storage had no appreciable effect on colour stability.     

Anti-inflammatory and antinociceptive effects of the stem bark of Byrsonima intermedia A. Juss

Ethnopharmacological relevance

Byrsonima intermedia A. Juss. is popularly known as “murici pequeno” and is native to the Brazilian Cerrado. This species has been used as an antimicrobial, anti-hemorrhagic, anti-diarrheal and anti-inflammatory. Nevertheless, scientific information regarding Byrsonima intermedia is limited; there are no reports related to its possible anti inflammatory and antinociceptive effects. This study employed in vivo inflammatory and nociceptive models to evaluate the scientific basis for the traditional use of Byrsonima intermedia.

Materials and methods

Carrageenan-induced paw edema, peritonitis and fibrovascular tissue growth induced by s.c. cotton pellet implantation tests were used to investigate the anti-inflammatory activity of Byrsonima intermedia aqueous extract (BiAE) in rats. Mechanical nociceptive paw, formalin and hot plate tests were used to evaluate the antinociceptive activity in mice. High-performance liquid chromatography (HPLC), phytochemistry screening and determination of total phenolics and flavonoids were used to determine the chemical profile of the BiAE.

Results

BiAE at test doses of 30-300 mg/kg p.o. clearly demonstrated anti-inflammatory effects by reduced carrageenan-induced paw edema, by inhibited leukocyte recruitment into the peritoneal cavity and, in the model of chronic inflammation, by using the cotton pellet-induced fibrovascular tissue growth in rats. The extracts at test doses of 30-300 mg/kg p.o. clearly demonstrated antinociceptive activity in all tests. Administration of the opioid receptor antagonist naloxone completely inhibited the antinociceptive effect induced by BiAE (100 mg/kg).

Conclusion

BiAE markedly exhibits anti-inflammatory action in rats and antinociceptive activity in mice. Thus, it may be useful in the treatment of inflammatory hyperalgesic disorders, which supports previous claims of its traditional use.     

Anti-inflammatory and analgesic properties of the stem bark extracts of Erythrophleum suaveolens (Caesalpiniaceae), Guillemin & Perrottet

The MeOH stem bark extract of Erythrophleum suaveolens dissolved in water and shaken up with ethylacetate (EtOAc) and fractionated on a polyamide column with methanol as eluent produced five principal fractions. These fractions were designated as fraction A (74.8 mg yield and rich in alkaloids), fraction B (36.6 mg), fraction C (7.8 mg yield, monomeric procyanidin), fraction D (26.6 mg yield, rich in monomeric and oligomeric procyanidin), and fraction E (18.1 mg yield, rich in polymeric procyanidin). The original MeOH extract administered (100 mg/kg po) produced about 47% inhibition of carrageenin-induced paw oedema 1 h after administration. Fraction D, obtained from the ethylacetate extract and rich in procyanidins produced over 33% inhibition of carrageenan-induced paw oedema while a dose of 19.2 microg/ml produced 100% inhibitory effect on 5-lipoxygenase. A dose of 100 mg/kg of the MeOH extract also produced over 30% reduction of the sensitivity to pain while 50 mg/kg of fraction D rich in procyanidins produced over 45% analgesic effects. These results were judged significant compared to those obtained with indomethacin and acetylsalicylic acid. These findings suggest that extracts of the bark of Erythrophleum suaveolens possess potent anti-inflammatory and analgesic property and that the procyanidins lead to the observable pharmacological effects.     

Studies on Bridelia ferruginea Leaves (1). Stability and Hypoglycaemic Actions of the Leaf Extract Tablets

The flavonoid content of 187.5 mg of Bridelia ferruginea leaf extract was calculated to be approximately 0.015% based on rutin. There was no significant difference ( p =0.05) in the mean values of flavonoids for the tabletted and untabletted extract. The moisture adsorption of the crude drug tablets was of Vander Waals type. The tablets showed a very long shelf life of about 96 years. A 25 mg/kg of B. ferruginea tablet lowered the blood glucose level of normal healthy rabbits by about 40%.     

Validation of use of a traditional remedy from Bridelia grandis (Pierre ex Hutch) stem bark against oral Streptococci

Aim of the study

Bridelia grandis (Pierre ex Hutch) (Euphorbiaceae) is a medicinal plant traditionally used in Cameroon by pygmies Baka as a remedy for oral cavity affection. Bioassay-guided stem bark extracts were investigated for their in vitro antimicrobial properties as well as their phytochemical constituents.

Materials and methods

The first extraction was carried out according to the traditional use. Further extractions were carried out with solvents of different polarity such as methanol (MeOH), ethyl acetate (EtOAc) and mixtures of MeOH–H₂O. The antimicrobial activity of the extracts against oral Streptococci was evaluated on the basis of the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) by the macrodilution method; the bacterial surface hydrophobicity was also evaluated.

Results

Water, methanol and mixtures methanol–water extracts, exhibited antibacterial activity with MIC between 0.5 and 2 mg/ml justifying the traditional use of Bridelia grandis stem bark for oral cavity affection. Preliminary phytochemical analysis was performed on the most active extract (methanol) using appropriate tests and well established analytical screening methods, such as TLC and RP-HPLC/DAD.

Conclusions

The data obtained indicate that tannins constitute the chemical family responsible for the biological activity.     

Anti-inflammatory and anti-nociceptive activities of the stem bark extracts from Allanblackia monticola STANER L.C. (Guttiferae)

THE AIM OF THIS STUDY: was to assess the anti-inflammatory and mechanism of action of Allanblackia monticola (Guttiferae). The anti-inflammatory activity "in vivo" of the methylene chloride/methanol extract, methanol and methylene chloride fractions of stem barks of Allanblackia monticola, administered orally at doses of 37.5; 75; 150 and 300 mg/kg, was evaluated on carrageenan-induced oedema in rats to determine the most active fraction. Indomethacin, inhibitor of cyclo-oxygenase was used as reference drug. The effects of the most active fraction were then examined on the rat paw oedema caused by histamine, serotonin, arachidonic acid and dextran followed by its ulcerogenic effect. The results showed that the methylene chloride fraction of Allanblackia monticola was more effective on the oedema caused by the carrageenan. The anti-nociceptive activity of the methylene chloride fraction was assessed using the acetic acid-induced abdominal constriction model, formalin test and hot plate test. At 150 mg/kg, Allanblackia monticola caused maximum inhibitions of inflammation induced by carrageenan (83.33%), by histamine (42.10%), by dextran (40.29%) and by arachidonic acid (64.28%). Allanblackia monticola (75-300 mg/kg) did not cause significant modification of the oedema induced by serotonin. Concerning the anti-nociceptive properties of the plant, the methylene chloride fraction (75-300 mg/kg) caused a dose-dependent inhibition on abdominal contractions induced by acetic acid (32.34-77.37%) and significantly inhibited the inflammatory pain caused by formalin (40.71-64.78%). Allanblackia monticola did not increase the latency time in the hot plate test. Like indomethacin (10mg/kg), the fraction at the dose of 150 mg/kg caused ulceration of the gastric mucous membrane in treated rats. These results show that Allanblackia monticola has an anti-inflammatory and analgesic activities with gastric ulcerative side effects.     

Coagulation of milk as an index of astringency of the bark extract of Bridelia ferruginea benth and lime juice for the formulation of a traditional gargle ‘Ogun Efu’

The extent of the coagulation of milk by the ethanolic extract of bark of Bridelia ferruginea and lime juice has been used to determine the effective concentrations of these two major astringent ingredients of a traditionally prepared herbal gargle ‘Ogun Efu’. Optimal concentrations of the bark extract and lime juice, respectively, were required to give maximum coagulate heights. Combinations of the bark extract with lime juice resulted in a synergistic effect on the coagulate heights obtained. The concentrations of Bridelia bark extract and lime juice (when combined) that gave the highest coagulate height were used as the basis for the laboratory formulation of the gargle. The coagulate heights obtained with the laboratory formulated products, compared with those obtained with the traditionally prepared products, indicate that the milk coagulation test method for the determination of the effective concentrations of the two ingredients is dependable.     

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 antitumoural effects of Uncaria guianensis bark

Ethnopharmacological relevance

Uncaria guianensis (Aublet) Gmell (Rubiaceae) is a medicinal plant from the jungles of South and Central America, used to treat cancer, arthritis, diabetes, and inflammation. Evaluate the anti-inflammatory and anti-tumor effects of Uncaria guianensis preparations.

Materials and methods

Bio-guided fractionation of a hydroethanolic extract of Uncaria guianensis was performed, evaluating the fractions and subfractions for their effect on inflammatory mediators, tumour necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and prostaglandin E₂ (PGE₂) by ELISA and nitric oxide (NO) by the Griess reaction in cultured supernatant from RAW 264.7 macrophages stimulated with lipopolysaccharide (LPS). The expression of cyclooxygenase 2 (COX-2), inducible nitric oxide synthase (iNOS) and inhibitor of κB (IκB) were investigated in RAW 264.7 macrophages by flow cytometry. The activity of NF-κB in HeLa cells transfected with a luciferase reporter system was determined. The effect of Uncaria guianensis on the inflammatory response in vivo was assessed in BALB/c mice stimulated with LPS, on rat paw oedema induced by carrageenan, and on tumour growth and lung metastasis in BALB/c mice inoculated with 4T1 mammary tumour cells. Immune cell infiltrates and inflammatory mediators were evaluated in the tumour by immunohistochemistry.

Results

Sub-fraction Ug AIV inhibited, to varying degrees, NO, TNF-α, IL-6 and PGE₂ production by macrophages in vitro (30 μg/ml) and in the serum of LPS-challenged mice (5 mg/kg). Macrophage expression of Cox-2 was inhibited (35%), IκB degradation was completely inhibited and NF-κB activation was inhibited (70%) by Ug AIV at 30 μg/ml. Ug AIV decreased paw oedema by 86% (5 mg/kg) and serum NO and TNF-α by 45% and 65% respectively. Ug AIV reduced 4T1 mammary tumour growth by 91% on day 33 post-inoculation as well as the levels of serum NO, IL-6 and TNF-α in the same animals. Ug AIV decreased the number of tumour-infiltrating T lymphocytes, macrophages and neutrophils as well as the number of cells positive for COX-2, iNOS, IL-6, TNF-α and p65.

Conclusions

As Ug AIV was not cytotoxic for tumour cells or macrophages, its anti-tumour effect may be due to a reduction in pro-tumoural inflammatory processes in the tumour microenvironment, possibly mediated through NF-κB.     

Studies on the anti-inflammatory, antipyretic and analgesic properties of Alstonia boonei stem bark

The methanol extract of the stem bark of Alstonia boonei was investigated for anti-inflammatory property. The analgesic and antipyretic properties of the extract was also evaluated. The extract caused a significant (P<0.05) inhibition of the carrageenan-induced paw oedema, cotton pellet granuloma, and exhibited an anti-arthritic activity in rats. Vascular permeability induced by acetic acid in the peritoneum of mice was also inhibited. The extract also produced marked analgesic activity by reduction of writhings induced by acetic acid, as well as the early and late phases of paw licking in mice. A significant (P<0.05) reduction in hyperpyrexia in mice was also produced by the extract. This study has established anti-inflammatory, analgesic and antipyretic activities of the stem bark of A. boonei.     

Antimicrobial properties of stem bark extracts from Phyllanthus muellerianus (Kuntze) Excell

Ethnopharmacological relevance

The plants of the genus Phyllanthus (Euphorbiaceae) are widely distributed in most tropical and subtropical countries, and have long been used in folk medicine to treat several diseases. Particularly, Phyllanthus muellerianus (Kuntze) Excell, commonly called “mbolongo” in Cameroon, is used by pygmies baka as a remedy for tetanus and wound infections.

Aim of the study

To investigate the antimicrobial properties of Phyllanthus muellerianus (Kuntze) Excell (family Euphorbiaceae) stem bark used in Cameroon by baka pygmies as a remedy for wound healing and tetanus.

Materials and methods

Aqueous and methanol extracts with and without defatting treatment, were prepared and their activity against Clostridium sporogenes ATCC 3584, Staphylococcus aureus ATCC 6538, Streptococcus mutans ATCC 25175, Streptococcus pyogenes ATCC 19615, Escherichia coli ATCC 10536, Candida albicans ATCC 10231, was evaluated on the basis of the minimum inhibitory concentration (MIC) and the minimum bactericidal-fungicidal concentration (MBC-MFC) by the macrodilution method.

Results

Water extract showed a weak activity against Clostridium sporogenes (MIC 900 μg/mL) and resulted inactive at the tested concentrations against all the other microorganisms. The defatted methanol extract, inactive against Staphylococcus aureus, Escherichia coli, Candida albicans, exhibited a very interesting activity against Clostridium sporogenes and Streptococcus pyogenes (MIC 100 μg/mL and 300 μg/mL, respectively), which seems to validate the use of this plant in pygmies traditional medicine for the treatment of tetanus and wound infections. The activity found against Streptococcus mutans (300 μg/mL), aetiological agent of caries, may suggest a possible use of this plant as natural remedy to prevent dental diseases.

Conclusions

The activity against streptococci and Clostridium sporogenes ATCC 3584, showed by stem bark extracts of Phyllanthus muellerianus, traditionally used by baka pygmies to treat wound infections and tetanus, is reported for the first time.     

Vasodilating properties of the stem bark extract of Mitragyna ciliata in rats and guinea pigs

Mitragyna ciliata is commonly used in traditional medicine for the treatment of inflammation, hypertension, headache, rheumatism, gonorrhoea and broncho-pulmonary diseases. In the present study, the vascular relaxant effect in the rat and guinea-pig was investigated. The extract induced aortic relaxation in a concentration-dependent manner, with an EC(50) of 1.3 and 7 microg/mL for the noradrenaline- and KCl-induced contractions, respectively. The relaxant effect of the extract on KCl-induced contractions was fi ve times greater than on noradrenaline-induced contractions. Moreover, the relaxant effect of the extract was higher in rat aortic rings with endothelium (104.67%) than without endothelium (49.44%). Chemical analysis of the extract showed the presence of alkaloids and flavonoids which may be responsible for the antihypertensive properties.     

Anti-inflammatory activity of methanol extract of Kalopanax pictus bark and its fractions

Dried pulverized bark of Terminalia arjuna Linn (TA) was administered orally to Wistar albino rats (120-150 g) in two doses [500 and 750 mg/kg in 2% carboxy methyl cellulose (CMC)], 6 days per week for 12 weeks. Thereafter, rats were sacrificed either for determination of baseline changes in cardiac endogenous antioxidant compounds [superoxide dismutase (SOD), reduced glutathione (GSH) and catalase (CAT)] or the hearts were subjected to oxidative stress associated with in vitro ischemic-reperfusion injury (IRI). There was significant increase in the baseline contents of thiobarbituric acid reactive substance (TBARS) (a measure of lipid peroxidation) with both doses of TA. However, only in the 500 mg/kg treated group, this was accompanied by a simultaneous increase in SOD, GSH and CAT levels, but not in the 750 mg/kg treated group, where only CAT was raised. Significant rise in myocardial TBARS and loss of SOD, CAT and GSH (suggestive of increased oxidative stress) occurred in the vehicle-treated hearts subjected to in vitro IRI. Only hearts, harvested from the 500 mg/kg rats treated rats, were significantly protected from oxidative stress, when subjected to in vitro IRI. The results suggest that crude bark of TA augments endogenous antioxidant compounds of rat heart and also prevents oxidative stress associated with IRI of the heart.     

Anti-inflammatory activity of Dalbergia lanceolaria bark ethanol extract in mice and rats

Topical anti-inflammatory activity of Dalbergia lanceolaria Linn. bark ethanol extract was demonstrated in albino mice using TPA-, EPP- and AA-induced ear edema models. The systemic activity of extract was confirmed using acute and sub-acute anti-inflammatory models in albino rats. The ethanol extract exhibited significant systemic anti-inflammatory activity in Carrageenan-induced rat paw edema, by inhibition of histamine and prostaglandin phases of acute inflammation. The extract also showed significant activity against turpentine-induced exudative changes and no activity against granular tissue formation in cotton pellet-induced granuloma in albino rats. Thus, resultant anti-inflammatory activity might be due to effects on several mediators involving cyclo-oxygenase pathway resulting in prostaglandin formation and leukocyte migration from the vessels.     

Anti-inflammatory and antipyretic properties of Clerodendrum petasites S. Moore

The methanol extract from Clerodendrum petasites S. Moore (CP extract) was assessed for anti-inflammatory and antipyretic activities on the experimental animal models. It was found that CP extract possessed moderate inhibitory activity on acute phase of inflammation in a dose-related manner as seen in ethyl phenylpropiolate-induced ear edema (ED(50)=2.34 mg/ear) as well as carrageenin-induced hind paw edema (ED(30)=420.41 mg/kg) in rats. However, CP extract did not elicit any inhibitory effect on arachidonic acid-induced hind paw edema in rats. In subchronic inflammatory model, CP extract provoked a significant reduction of transudation but had no effect on proliferative phase when tested in cotton pellet-induced granuloma model. CP extract also reduced the alkaline phosphatase activity in serum of rats in this animal model. Moreover, CP extract possessed an excellent antipyretic effect when tested in yeast-induced hyperthermic rats. It is postulated that the anti-inflammatory and antipyretic effects of CP extract are caused by the inhibition of the prostaglandin synthesis. Anyhow, CP extract did not possess any analgesic activity in acetic acid-induced writhing response in mice. The results obtained show that C. petasites has beneficial properties since it possesses potent antipyretic and moderate anti-inflammatory activities without ulcerogenic effect.