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 N(ω)-nitro-L-arginine (LNA 300 µmol/L, an inhibitor of endothelial NO synthase), but not affected by charybdotoxin (CTX, 100 nM) plus apamin (APA, 100 nM) (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 (Ba(2+), 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]-quinoxalin1-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.

Knowledge and adherence to antiretroviral therapy among adult people living with HIV/AIDS treated in the health care centers of the association "Espoir Vie Togo" in Togo, West Africa.

BACKGROUND: The efficiency of antiretroviral therapy (ART) depends on a near perfect level of patients' adherence. The level of adherence of adults HIV-infected patients treated in the HIV/AIDS health care centres of the association "Espoir Vie Togo" in Togo, West Africa is not properly documented. The aim of the present study was to examine by means of self-reports the knowledge, the adherence level and associated factors to antiretroviral therapy (ART) among these patients. METHODS: We conducted a cross-sectional survey among adult people living with HIV/AIDS (PLWHA) through a structured questionnaire. RESULTS: A total of 99 patients were enrolled. Among them, 55.6% knew the name of antiretroviral agents of regimens prescribed. All patients had a good knowledge of treatment schedule. The treatment regimens based on 2 NRTIs + 1 NNRTI were used in 90% of patients. The average adherence rate was 89.8% of the total doses prescribed while 62.62% of patients showed an adherence rate of 95% or above. The treated groups were similar in term of median % of medication doses taken according to PLWHA epidemiological characteristics. However, patients reported forgetting (34.9%), travel (25.6%), cost of treatment (13.9%) and side effects (11.6%) as the main factors of missing at least once a dose intake. CONCLUSION: These results should encourage the association and all the involved actors in the HIV/AIDS's program to strengthen counseling, education and information interventions for HIV-infected patients in order to overcome the potential barriers of poor adherence.

Antiplasmodial activity and toxicity of crude extracts from alternatives parts of plants widely used for the treatment of malaria in Burkina Faso: contribution for their preservation.

In order to prevent the destruction of the ecology and to sustain the flora mainly for medicinal plants, we investigated on alternative parts taken from four plants already known to display antiplasmodial activities and largely used by traditional healers in sub-Saharan Africa. The evaluated parts are bark of trunk for Zanthoxylum zanthoxyloides and leaves for Sarcocephalus latifolius instead of roots, and leaves for Combretum molle and Anogeissus leiocarpus instead of stem bark. The antiplasmodial activity of extracts of these plants was evaluated in vitro using the multi-resistant strain (W2) of Plasmodium falciparum. Antiproliferative activity was also assessed, using K562S human monocyte cell lines, along with calculation of the selectivity index (SI) of each extract. The highest in vitro antiplasmodial activity was found in the alkaloid extract of trunk bark from Z. zanthoxyloides and from the MeOH extract of A. leiocarpus leaves (IC(50) = 1.2 microg/mL and 4.9 microg/mL, respectively) with good selectivity index. Moderate activity was found in the MeOH extract (IC(50) = 5.7 microg/mL) and MeOH/H2O extract (IC(50) = 7.9 microg/mL) of C. molle leaves. Moderate activity was also found in the MeOH/H20 extract (IC(50) = 5.2 microg/mL) and the decoction (IC(50) = 8.2 microg/mL) from leaves of A. leiocarpus. No good activity was found with extracts from roots of S. latifolius. All extracts tested displayed low levels of cytotoxicity against K562S cells. The data generated clearly show that the trunk bark for Z. zanthoxyloides and the leaves for A. leiocarpus and C. molle could be used for the treatment of malaria instead of roots and stem bark.

Prescription drugs among pregnant women in Lome, Togo, West Africa.

OBJECTIVE: To assess the trends in prescription drugs and the potential repercussions to newborns among pregnant women who attended prenatal consultations and gave birth in the Department of Gynaecology of Tokoin's University Hospital, Lome (Togo). METHODS: A retrospective study of the registers of prenatal visits and deliveries of the eligible population was performed. RESULTS: In total, 184 different drugs were prescribed to 627 pregnant women attending prenatal consultations. The profile of pharmacotherapeutic groups prescribed was: anti-anaemics (33.33%), antimalarial drugs (24.75%), vitamins +/- mineral salts, amino acids and appetite stimulants (14.96%) and antispasmodics and anti-emetics (7.22%). The median proportion of prescriptions for each pharmacotherapeutic group increased significantly from the first to third trimester (9.72, 25.17 and 64.00 respectively; P < 0.05). The median number of drugs prescribed did not vary significantly (P = 0.051) with the age groups, parity (P = 0.068) or obstetrical-gynaecological history (P = 0.401); it did, however, increase significantly with the medical-surgical history (P < 0.05). There were complications associated with deliveries that had no obvious cause related to drug prescription, including four cases of minor defects, 28 stillborns, 65 cases of low birth weight and 27 hospitalised newborns for neonatal diseases. Some interventions were needed for safeguarding the health of the mother, the foetus and the newborn. CONCLUSION: The trends in obtaining prescription drugs and the consumption of drugs by pregnant women can be assessed using multiple parameters. We limited our study to age groups, gestational age, parity and the medical history of the pregnant woman, profile of pharmacotherapeutic groups, median number of drugs prescribed and the potential risks of the drugs used. The results of our retrospective study were not alarming in terms of neonatal outcomes.