Preliminary studies of acute and sub-chronic toxicity of the aqueous extract of Guibourtia tessmannii (Harms) J. Leonard stem barks (Caesalpiniaceae) in mice and rats

AbstractObjectiveTo investigate the toxicity of aqueous extract of Guibourtia tessmannii (Harms) J. Leonard (G. tessmannii) and evaluate its safety.MethodsNMRI mice were used to determine the acute toxicity of G. tessmannii. Increasing concentrations of the plant extracts were administered intraperitoneally or by force-feeding. General behavior and death were monitored and recorded daily for 7 days. In order to determine the sub-acute toxicity of the extract, several doses were administered by oral gavage daily for 28 days in adult Wistar rats. Different parameters were assessed including body weight, food and water intake, biochemical parameters and several vital organ weights.ResultsLD50 of 328.78 mg/kg was obtained by i.p. route and more than 5000 mg/kg was obtained in acute toxicity by oral route. In sub-acute toxicity, no significant alteration was observed in body weight or vital organs, food and water intake, and biochemical parameters.ConclusionsThe results showed that the aqueous extract of G. tessmannii has low toxicity intraperitoneally and no sub-acute toxicity via oral intake

HPLC ANALYSIS AND ANTI-INFLAMMATORY PROPERTIES STUDIES OF TRUNK BARKS OF ACACIA NILOTICA VAR ADANSONII (GUILL AND PERR) O KTZE (MIMOSACEAE)

Objective: The objective of this study was to evaluate the in vitro and in vivo anti-inflammatory properties of the aqueous extract and fractions of the trunk bark of Acacia nilotica. Methods: A maceration of the powder of the trunks barks of the plant was realized. Then the aqueous macerate obtained was fractionated with dichloromethane, butanol and ethyl acetate successively. The phenolic compounds of the aqueous extract, butanol and ethyl acetate fractions were identified by HPLC/DAD. Lipoxygenase and phospholipase inhibition tests with the aqueous extract and the butanol and ethyl acetate fractions were carried out. The anti-inflammatory potential of the aqueous extract was assessed in vivo by the anti-edema test with carrageenan and the analgesic test with acetic acid at different doses (200 mg/ml; 400 mg/ml; 600 mg/ml). Aspirin (200 mg/ml) and paracetamol (200 mg/ml) were used as a reference. Results: The HPLC/DAD analysis of the extracts revealed that gallic acid is the most abundant phenol acid in the extracts. The aqueous extract inhibited lipoxygenase (IC50 = 18.32±1.18 μg/ml), phospholipase (11.44±0.32% per 100 μg/ml) and cyclooxygenase (56.48±0.29% for 100 μg/ml) as well as its tested fractions. It also reduced edema and pain in the mice by more than 50% from the 400 mg/ml dose. Conclusion: Aqueous extract of Acacia nilotica has anti-inflammatory properties. Hence its use in traditional medicine in the treatment of inflammation

Pharmacological study of trunk bark of Acacia nilotica var adansonii (Guill et Perr).o Ktze (Mimosaceae): Assays, antioxidant and antispasmodic activities

Aim of this study was to evaluate in vitro polyphenols content, antioxidant and antispasmodic properties of the aqueous extract and fractions of the trunk bark of Acacia nilotica. According to a survey conducted in rural Burkina Faso, Acacia nilotica var. adansonii (Guill and Perr). Ktze reported to be widely used in the treatment of gastrointestinal diarrhoea and parasitosis. A maceration of the powder of the trunk bark of the plant was carried out. Then the aqueous macerate obtain, was fractionated with dichloromethane, butanol and ethyl acetate successively. The phenolic compounds of the aqueous extract, butanol and ethyl acetate fractions was determinated. The antioxidant activity of aqueous extract and fractions was evaluated by the DPPH, ABTS and FRAP tests. The contractility test on smooth muscle was realized according to Magnus method. Assay of the extracts revealed a high content of polyphenols, tannins and flavonoids. The aqueous extract, the butanol fraction and the ethyl acetate fraction demonstrated a high antioxidant capacity. Aqueous extract showed a better antispasmodic effect of acetylcholine contraction induction at 1 μM (IC50 = 13.02 μg / mL) and for BaCl2 at 160 μg / mL (IC50 = 117.2 μg / mL). The aqueous extract of Acacia nilotica and his fractions had antioxidant properties. Only aqueous extract proven better antispasmodic property. Hence its use in traditional medicine in the treatment of diarrhoea. Keywords: Acacia nilotica, Antioxidant, Antispasmodi

ACUTE TOXICITY AND VASCULAR PROPERTIES OF SEED OF PARKIA BIGLOBOSA (JACQ) R. BR GIFT (MIMOSACEAE) ON RAT AORTA.

The authors report here the results of study on Parkia biglobosa seeds used in Burkina Faso for arterial hypertension treatment. Investigations were done on acute toxicity and vascular properties of fermented and roasted seeds. Acute toxicity test using mice, revealed by the intraperitoneal route a lethal dose 50 (LD50) of 1800 mg/kg and 1600 mg/kg of body weight for aqueous extract from roasted and fermented seeds respectively. According to the scale of Hodge and Sterner and that of the World Health Organization, such drugs would be classified lightly toxic. Oral administration (up to 3000 mg/kg) did not induce any death of animal. For the vascular properties, the effects of these products were tested on the aorta isolated from rats. The cumulative administration of extract from roasted and fermented seeds (0.1-10 mg/mL) in an organ bath induced a concentration-dependent relaxation of the aorta pre contracted by phenylephrine, with or without functional endothelium. The extracts (10 mg/mL) inhibited for 100% the contraction induced by phenylephrine. The EC50 values in presence and absence of endothelium were respectively of 5.37 ± 0.12 and 4.19 ± 1.02 mg/mL for fermented seeds; for roasted seeds these values were respectively, 5.39 ± 1.12 and 5.93 ± 0.95 mg/mL. Nevertheless, low concentration of roasted seeds (1-4 mg/mL) induced endothelium-dependent relaxation and this effect was inhibited by indomethacin (10-5M), and not by L-NAME (310-4M). These experimental results revealed a vasorelaxant effect of P. biglobosa seeds. P. biglobosa seems to act directly on the smooth muscle and via endothelium involving the generation of vasodilatating prostaglandins. This vasodilator effect would be in favor of an anti hypertensive property of P. biglobosa seeds

ENDOTHELIUM-INDEPENDENT AND ENDOTHELIUM-DEPENDENT VASORELAXATION BY A DICHLOROMETHANE FRACTION FROM ANOGEISSUS LEIOCARPUS (DC) GUILL. ET PERR. (COMBRETACEAE): POSSIBLE INVOLVEMENT OF CYCLIC NUCLEOTIDE PHOSPHODIESTERASE INHIBITION.

Many traditional medicinal herbs from Burkina Faso are used to treat arterial hypertension (HTA). Among them, Anogeissus leiocarpus (A. Leiocarpus) which is well known and widely used in Burkina traditional medicine. Herein we assess the effects of dichloromethane fraction from A. leiocarpus stem bark (ALF), selected as the most active on cyclic nucleotide phosphodiesterases (PDEs) and characterized its specificity towards purified vascular PDE1 to PDE5 isoenzymes and study its effects on a vascular model. ALF potently and preferentially inhibits (IC50=1.6 ± 0.6 µg/mL) the calmodulin-dependent phosphodiesterase PDE1, being mainly present in vascular smooth muscle and preferentially hydrolyses cGMP. In the same range (IC50 =2.8 ±0.2 µg/ml) ALF inhibits PDE2, a cGMP-activated enzyme that is only present in endothelial cells and hydrolyses both cAMP and cGMP. PDE5, which specifically hydrolyses cGMP and which mainly contributes to cGMP hydrolysis is also potently inhibited by ALF (IC50=7.6±3.5 µg/ml). The potencies of ALF on cAMP hydrolyzing isoenzymes was lesser, being more effective on PDE4 (IC50= 17.6±3.5 µg/ml) than on PDE3 (60.9 ± 1.8 µg/ml). Since the major effect of ALF were against cGMP hydrolysis and since cGMP is implicated in endothelium-dependent relaxation, the endothelium-dependent vasorelaxation was studied on isolated porcine coronary arteries rings pre-contracted with U46619. The endothelium-dependent vasorelaxation is significantly inhibited by Nω-nitro-L-arginine (LNA 300 µmol/L, an inhibitor of endothelial NO synthase), but not affected by charybdotoxin (CTX, 100nM) plus apamin (APA, 100nM) (two inhibitors of EDHF-mediated responses). The combination of 4-aminopyridine (4-AP, 1 mmol/L, inhibitor of voltage-dependent potassium channels, Kv) plus baryum (Ba2+, 30 µmol/L, inhibitor of the potassium channels with entering correction, Kir) plus ouabain (3 µmol/L, inhibitor of ATPase Na+/K+ channels) partially inhibits endothelium-independent vasorelaxant effect. This endothelium-independent relaxant effect was also sensitive to combination of 1H-[1,2,4]-oxadiazole-[4,3-α]-quinoxalin-1-one (ODQ, 10 µM, soluble guanylyl cyclase inhibitor) and N-[2-(p-Bromocinnamylamino)ethyl]-5-isoquinoline sulfonamide dihydrochloride (H89, 100 nM, Protein Kinase A inhibitor). Taken together, these results indicate that ALF is a powerful vasodilator modulated by the formation of NO from endothelium, but also act by directly relaxing the vascular smooth muscle cells, by inhibiting cGMP hydrolyzing PDEs (PDE1, PDE2 and PDE5) and to a lesser extend on cAMP degradation (PDE3 and PDE4), cAMP and cGMP being second messengers involved in vascular relaxation

PHARMACOLOGICAL EVALUATIONS FOR THE RELAXANT EFFECT OF THE HYDROALCOHOLIC EXTRACT OF TAPINANTHUS DODONEIFOLIUS ON RAT TRACHEA

The present study was designed to investigate the blocking of calcium by the hydroalcoholic extract of Tapinanthus dodoneifolius (Tapidod), "in vitro", on rat trachea. To evaluate this effect, the contractile activity of tracheal chains from Wistar Kyoto rats was isometrically recorded. On the isolated tracheal rings the extract produced the following effects: (a) a reduction of the contraction obtained by BaCl2, (b) a bronchorelaxing action, on strips precontracted by KCl, which was not influenced by TEA (3x10-3 M), (c) a concentration-dependent decrease of the spasm evoked by calcium chloride (CaCl2) in K+-rich Ca2+-free physiological salt solution, before and after intracellular calcium depletion (d), an inhibitory effect on contraction induced by acetylcholine in Ca2+-free Krebs-Heinseleit solution supplemented with EDTA (5x10-4M). It is concluded that: 1. The activation of the potassium channels does not play a significant role in the relaxant effect of Tapidod. 2. The antispasmodic property of Tapidod seems to be mediated by the blockade of intracellular Ca2+ release. 3. Most likely an inhibition of the intracellular Ca2+-regulating proteins is involved

Research Paper - PHARMACOLOGICAL EVALUATIONS FOR THE RELAXANT EFFECT OF THE HYDROALCOHOLIC EXTRACT OF TAPINANTHUS DODONEIFOLIUS ON RAT TRACHEA

The present study was designed to investigate the blocking of calcium by the hydroalcoholic extract of Tapinanthus dodoneifolius (Tapidod), "in vitro" on rat trachea. To evaluate this effect, the contractile activity of tracheal chains from Wistar Kyoto rats was isometrically recorded. On the isolated tracheal rings the extract produced the following effects: (a) a reduction of the contraction obtained by BaCl2, (b) a bronchorelaxing action, on strips precontracted by KCl, which was not influenced by TEA (3x10-3 M), (c) a concentration-dependent decrease of the spasm evoked by calcium chloride (CaCl2) in K+-rich Ca2+-free physiological salt solution, before and after intracellular calcium depletion (d), an inhibitory effect on contraction induced by acetylcholine in Ca2+-free Krebs-Heinseleit solution supplemented with EDTA (5x10-4M). It is concluded that: 1. The activation of the potassium channels does not play a significant role in the relaxant effect of Tapidod. 2. The antispasmodic property of Tapidod seems to be mediated by the blockade of intracellular Ca2+ release. 3. Most likely an inhibition of the intracellular Ca2+-regulating proteins is involved

Pharmacological Evaluations for the Relaxant Effect of the Hydroalcoholic Extract of Tapinanthus dodoneifolius on Rat Trachea

The present study was designed to investigate the blocking of calcium by the hydroalcoholic extract of Tapinanthus dodoneifolius (Tapidod), \"in vitro\", on rat trachea. To evaluate this effect, the contractile activity of tracheal chains from Wistar Kyoto rats was isometrically recorded. On the isolated tracheal rings the extract produced the following effects: (a) a reduction of the contraction obtained by BaCl2, (b) a bronchorelaxing action, on strips precontracted by KCl, which was not influenced by TEA (3x10-3 M), (c) a concentrationdependent decrease of the spasm evoked by calcium chloride (CaCl2) in K+ -rich Ca2+ -free physiological salt solution, before and after intracellular calcium depletion (d), an inhibitory effect on contraction induced by acetylcholine in Ca2+ -free Krebs-Heinseleit solution supplemented with EDTA (5x10-4M). It is concluded that: 1. The activation of the potassium channels does not play a significant role in the relaxant effect of Tapidod. 2. The antispasmodic property of Tapidod seems to be mediated by the blockade of intracellular Ca2+ release. 3. Most likely an inhibition of the intracellular Ca2+-regulating proteins is involved. Key Words: Extract of Tapinanthus dodoneifolius (Tapidod); Trachea; Calcium. Afr. J. Trad. CAM (2005) 2 (2): 166-17

Prevalence and risk factors of wax moth in bee colonies in the Central and Central-West regions of Burkina Faso: pilot study

Beekeeping is a very old practice in Burkina Faso and has many advantages, including the availability of honey resources, of endogenous knowledge and support from public policies. However, it faces challenges, including health problems, which are poorly documented. This cross-sectional study was conducted between March and May 2019 in the Central and Central-west regions of Burkina Faso to determine the prevalence and risk factors of wax moth in bee colonies. A total of 200 modern hives were visited of which 106 were colonized or previously colonized. Methods of observation and inspection of the hives were used to search for witnesses of the wax moth infestation: eggs, larvae, pupae cocoons, woven silk cloth, gallery in wax or adult butterflies. A pre-tested questionnaire was used to collect information on beekeepers and apiaries characteristics. An inspection sheet was used to record observations made during the inspection of the hives. The results revealed that the average size was 18 hives by apiary. Hives used were Kenyan, Dadant, and rectangular frame hives with a colonization rate of 53%. The overall prevalence of wax moth was 23.6% [15.5-31.7%]. Other predators/pests were observed in 43.4% of the hives, the main ones being beetles (25.5%) and ants (17%). The analysis of the radio adjusted odds ratio showed the absence of risk factors among the modalities of the studied variables. In view of the results of this pilot study, more extensive studies could be carried out to have a better understanding of the epidemiology of the infestation and its possible impact that it can have on honey production