P-334 Are measurements of patient-centeredness of endometriosis care and quality of life in women with endometriosis associated?

Study question

To examine the hypothesis that experiences with patient-centred endometriosis care are associated with the endometriosis-specific quality of life dimensions ‘emotional wellbeing’ and ‘social support’.

Summary answer

Positive associations were found between experienced patient-centeredness of care and the quality of life domains ‘emotional well-being’ and ‘social support’.

What is known already

Women with endometriosis have lower quality of life. Furthermore, research showed that the patient-centeredness of endometriosis care could still be improved. The quality of the provided endometriosis care might impact women’s quality of life, as demonstrated in the field of fertility care. A previous explorative study identified associations between patient-centred endometriosis care and two in five dimensions of endometriosis-specific quality of life (i.e. ‘emotional well-being’ and ‘social support’) but concluded that a more focussed and adequately powered study was needed.

Study design, size, duration

A secondary regression analysis of two cross-sectional cohort studies was performed. Both studies investigated patient-centeredness of endometriosis care and endometriosis-specific quality of life using respectively the ENDOCARE questionnaire (ECQ) and the Endometriosis Health Profile 30 (EHP-30). In total the data from 300 women was eligible for analysis, exceeding the, according to our power calculation, required sample size of 200 women.

Participants/materials, setting, methods

The participating women all had surgically proven endometriosis and were recruited by one secondary and two tertiary endometriosis clinics in the Netherlands. The regression analysis focused on the previously found association between the ten dimensions of the ECQ and the EHP-30 domains ‘emotional well-being’ and ‘social support’ rather than all five EHP-30 domains. After the Bonferroni correction to limit type I errors, the adjusted p-value was 0.003 (0.05/20).

Main results and the role of chance

The participating women had a mean age of 35.7 years and had predominantly been diagnosed with moderate to severe (68.6%). Regarding the EHP-30 domain ‘emotional well-being’, an association was found with the following five patient-centeredness dimensions: ‘respect for patients’ values, preferences and expressed needs’ (p = 0.046, Beta=0.159), ‘coordination and integration of care’ (p = 0.013, Beta=0.193), ‘information, communication and integration of care’ (p = 0.010, Beta=0.258), ‘emotional support and alleviation of fear and anxiety’ (p = 0.010, Beta=0.178), and ‘continuity and transition’ (p = 0.015, Beta=0.179). None of the associations between the EHP-30 domain ‘emotional well-being’ and a dimension of patient-centred endometriosis care, were significant when compared to the Bonferroni corrected p-value (all p ≥ 0.010). The EHP-30 domain ‘social support’ proved to be significantly associated to the following three dimensions of patient-centered endometriosis care (in order of strength): ‘information, communication and integration of care’ (p < 0.001, Beta=0.436), ‘coordination and integration of care’ (p = 0.001, Beta=0.307), and ‘emotional support and alleviation of fear and anxiety’ (p = 0.002, Beta=0.259).

Limitations, reasons for caution

This cross-sectional studies identified associations rather than proving causality between experiencing less patient-centeredness of care and having lower quality of life. Nevertheless, it is very tangible that some causality exists, either directly or indirectly (e.g. through empowerment) and that by improving patient-centeredness, quality of life might be improved as well.

Wider implications of the findings

Improving the patient-centeredness of endometriosis care was already considered an important goal, but even more so given its association with women’s quality of life, which is increasingly considered the ultimate measure of health care quality.

Trial registration number

not applicable

Tropical Peatland Hydrology Simulated With a Global Land Surface Model

Tropical peatlands are among the most carbon-dense ecosystems on Earth, and their water storage dynamics strongly control these carbon stocks. The hydrological functioning of tropical peatlands differs from that of northern peatlands, which has not yet been accounted for in global land surface models (LSMs). Here, we integrated tropical peat-specific hydrology modules into a global LSM for the first time, by utilizing the peatland-specific model structure adaptation (PEATCLSM) of the NASA Catchment Land Surface Model (CLSM). We developed literature-based parameter sets for natural (PEATCLSM_Trop,Nat) and drained (PEATCLSM_Trop,Drain) tropical peatlands. Simulations with PEATCLSM_Trop,Nat were compared against those with the default CLSM version and the northern version of PEATCLSM (PEATCLSM_North,Nat) with tropical vegetation input. All simulations were forced with global meteorological reanalysis input data for the major tropical peatland regions in Central and South America, the Congo Basin, and Southeast Asia. The evaluation against a unique and extensive data set of in situ water level and eddy covariance-derived evapotranspiration showed an overall improvement in bias and correlation compared to the default CLSM version. Over Southeast Asia, an additional simulation with PEATCLSM_Trop,Drain was run to address the large fraction of drained tropical peatlands in this region. PEATCLSM_Trop,Drain outperformed CLSM, PEATCLSM_North,Nat, and PEATCLSM_Trop,Nat over drained sites. Despite the overall improvements of PEATCLSM_Trop,Nat over CLSM, there are strong differences in performance between the three study regions. We attribute these performance differences to regional differences in accuracy of meteorological forcing data, and differences in peatland hydrologic response that are not yet captured by our model.

O-168 Chronic pelvic pain is the most troublesome endometriosis pain symptom for women’s quality of life

Study question

Which pre-operative endometriosis pain symptom is most troublesome for the quality-of-life of women assessed at different meta-levels?

Summary answer

Of five pain symptoms chronic pelvic pain is most troublesome or has the strongest correlation to women’s overall quality-of-life and overall and endometriosis-specific health status.

What is known already

Endometriosis affects women’s quality of life negatively, and its impact seems to depend more on women’s symptoms than on their degree of endometriosis. Experts proposed to include ‘the most troublesome symptom’ and ‘overall pain’ as core outcomes but did not define how to assess these outcomes. It would be interesting to find out which pain symptom (i.e. assessed for presence and intensity) has most impact on women’s quality-of-life assessed at different meta-levels, including: overall quality-of-life (depending on amongst others one’s professional and relational life besides health), general health status and endometriosis-specific health status.

Study design, size, duration

A prospective survey addressed 277 adult women scheduled for diagnostic and/or therapeutic surgery in a University endometriosis clinic between October 2016 and November 2019. Women were reminded twice of our request to fill out the coded but anonymous questionnaire package assessing five pain symptoms (i.e. chronic pelvic pain, dysmenorrhea, dyspareunia, dysuria and dyschezia) and assessing quality-of-life at three different meta-levels.

Participants/materials, setting, methods

Women scored five endometriosis symptoms between 0 (no pain) and 10 (worst imaginable pain), combined into ‘overall pain’ (0-50). ‘Overall quality-of-life’ was assessed with the Linear Analogue Scale (LAS; the higher, the better). General and endometriosis-specific health status were assessed with the overall scores of the EuroQol-5D and the Endometriosis-Health-Profile-30 (the higher, the better). Pearson correlation coefficients between the six pain scores and three measures of quality-of-life were computed (p = 0.003; 0.05/18 as Bonferroni correction).

Main results and the role of chance

A total of 227 women took part (participation rate=82%) and the data of 202 women (mean age 31±5 years old) with surgically confirmed endometriosis were analysed. In the previous six months, the majority of women reported chronic pelvic pain (56%), dyspareunia (55%), dysmenorrhea (56%) and/or dyschezia (58.4%), while only some reported dysuria (25%). Women’s mean overall pain score was 20 (±12). Women’s mean overall quality-of-life was 65 (±16). On average women rated their general health status to be 62 (±18) and their mean endometriosis-specific health status was 53 (±18). Only the pain symptom chronic pelvic pain was correlated (p < 0.001) to assessments of quality-of-Life at all three meta-levels. The correlation for endometriosis-specific health status was large (r= -0.574), while the others were medium (r= -0.343 & r= -0.324). After taking account of the Bonferroni correction for multiple testing the remaining four pain symptoms only had a medium correlation (p < 0.001) to endometriosis-specific health status (r= -0.356 – -0.265; p < 0.001) and they were not correlated to overall quality-of-Life or general health status. Overall pain had a medium correlation (p < 0.001) to Overall quality-of-Life (r= -0.270) and general health status (r= -0.259) and a strong correlation (p < 0.001) to endometriosis-specific health status (r= -0.529).

Limitations, reasons for caution

The majority of patients (60%) of the recruiting University endometriosis clinic had severe endometriosis (AFS-IV) and this study could be repeated in another setting. Directly asking women which pain symptom is most troublesome to them would be interesting besides exploring correlations between pain symptoms and quality of life.

Wider implications of the findings

Nurses, midwives and other health care professionals should devote attention to chronic pelvic pain during the anamnesis and women-centred care as this pain symptom is most troublesome for women’s quality of life. Whether surgery decreases chronic pelvic pain and overall pain is currently followed-up in the studied prospective cohort.

Trial registration number

Not applicable

The stepwise development of an interactive web-based sex education programme for subfertile couples: the Pleasure & Pregnancy programme

STUDY QUESTION

Can we develop a web-based sex education programme (programme running in a web browser) that addresses the needs of subfertile couples who are advised expectant management for at least 6 months?

SUMMARY ANSWER

The 'Pleasure & Pregnancy' programme addresses couples' needs, is likely to improve couples' sexual functioning, and is subsequently hypothesised to improve the chance of natural pregnancy.

WHAT IS KNOWN ALREADY

According to professional guidelines (e.g. the Netherlands and UK) couples with unexplained subfertility and a good chance of natural pregnancy, should be advised at least 6 months of expectant management. Adherence to expectant management is challenging as couples and gynaecologist prefer a more active approach. Targeting sexuality may be useful as subfertility is a risk factor for decreased sexual functioning.

STUDY DESIGN, SIZE, DURATION

A novel programme was developed according to the three steps of the Medical Research Councils' (MRC) framework. First, relevant literature was explored. Second, an interdisciplinary expert panel developed a theory (based on a systematic literature review and patient interviews) on how the chance of natural conception can be improved. Third, the expected process and outcomes were modelled.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Two licenced clinical sexologists, two gynaecologists, a clinical embryologist and two midwife-researchers, all from Belgium and the Netherlands, proposed components for the sex education programme. PubMed was searched systematically for randomised controlled trials (RCTs) evaluating the proposed components in different patient populations. The needs of 12 heterosexual Dutch or Belgian couples who were advised expectant management were explored with in-depth interviews. The content and delivery characteristics of the novel programme were described in detail with the aid of 'Intervention Taxonomy'. To model the outcomes, a protocol for an RCT was designed, registered and submitted for publication.

MAIN RESULTS AND THE ROLE OF CHANCE

To help maintain or improve sexual functioning, mainly pleasure, and hence increase pregnancy rates, the web-based Pleasure & Pregnancy programme contains a combination of psychosexual education and couple communication, mindfulness and sensate focus exercises. Information on the biology of conception and interaction with fertility clinic staff and peers were added based on couples' needs to increase potential acceptability.

LIMITATIONS AND REASON FOR CAUTION

This paper outlines the development phase of a sex education programme according to the MRC-framework. Whether the Pleasure & Pregnancy programme actually is acceptable, improves sexual functioning, increases pregnancy rates and is cost-effective remains to be determined.

WIDER IMPLICATIONS OF THE FINDINGS

No previous interactive web-based sex education programme has aimed to increase the natural pregnancy rate of subfertile couples by targeting their sexual pleasure. The Pleasure & Pregnancy programme addresses couples' needs and its effect on sexual functioning and pregnancy rate is plausible but remains to be demonstrated by an RCT which is currently ongoing.

STUDY FUNDING/COMPETING INTEREST(S)

Funding was provided by The Netherlands Organisation for Health Research and Development (ZonMw), Flanders Research Foundation and the University of Amsterdam. C.B.L. is editor-in-chief of Human Reproductionbut was blinded to all parts of the peer review process. The remaining authors have no conflict of interest to report.

TRIAL REGISTRATION NUMBER

Not applicable.

A systematic review and secondary analysis of two studies identifying demographic and medical characteristics determining patient-centeredness in endometriosis care as experienced by patients

STUDY QUESTION

What are the patient-specific determinants associated with patient-centered endometriosis care as measured by the ENDOCARE questionnaire (ECQ)?

SUMMARY ANSWER

‘Overall grade for endometriosis care’, ‘educational level’, ‘membership of a patient organization’ and ‘having seen other specialists for endometriosis complaints’ are correlated with overall patient-centeredness scores (PCS).

WHAT IS KNOWN ALREADY

Patient-centeredness of endometriosis care can be evaluated using the validated ECQ. The ECQ leads to an overall PCS and separate PCS for 10 dimensions of endometriosis care. Previously, educational level and quality of life scores were found to be associated with ECQ results.

STUDY DESIGN, SIZE, DURATION

First, a systematic literature review was performed (PROSPERO registration number: CRD42020169872). MEDLINE, Cochrane CENTRAL and EMBASE databases were searched from inception to May 2020 for studies in any language reporting on the results of the ECQ in patients with endometriosis. Two studies were identified. From the two studies, all original data were merged. In total, data from 546 patients were available for analysis. Second, univariate and multivariate regression analyses were performed to identify determinants for patient-centeredness of endometriosis care.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The two included studies evaluated patient-centeredness in four endometriosis care centers in Belgium and the Netherlands. All participants had surgically proven endometriosis. Possible patient-specific determinants were selected from the demographic and medical questions from the first part of the ECQ. These determinants were evaluated using linear regression analysis and all possible determinants with a P > 0.2 in the univariate analysis were selected for stepwise multivariate analysis. Separate analyses were performed for overall PCS and each of the 10 dimensions.

MAIN RESULTS AND THE ROLE OF CHANCE

The two included studies provided data from 546 patients. After adjustment for care center, multivariate analysis showed that a higher ‘grade for endometriosis care’ (B = 0.66), a ‘lower educational level’ (B = 0.50), ‘being member of a patient organization’ (B = 0.49) and ‘having seen other specialists for endometriosis complaints’ (B = 0.34) were independently associated with higher overall PCS (R² = 0.41). ‘Grade for endometriosis care’ was a determinant for all dimensions of endometriosis care. ‘Having seen other specialists for endometriosis complaints’ was positively associated with the care dimensions ‘respect for patients’ values, preferences and expressed needs’, ‘continuity and transition’ and ‘technical skills’. Members of a patient organization showed higher scores on the care dimensions ‘emotional support and alleviation of fear and anxiety’, ‘continuity and transition’ and ‘endometriosis clinic staff’. Furthermore, we found that having a higher level of education is associated with lower scores in the care dimensions ‘physical comfort’, ‘emotional support and alleviation of fear and anxiety’ and ‘involvement of significant other’.

LIMITATIONS, REASONS FOR CAUTION

These results delineate the patient-specific determinants of patient-centered care as measured using the Dutch ECQ. Whether results are generalizable to other countries should be investigated in an international study. This requires the ECQ to be validated in other languages first.

WIDER IMPLICATIONS OF THE FINDINGS

The aforementioned determinants of patient-centered care are of value for studies benchmarking clinics for their patient-centeredness. In addition, they help clinicians to determine how to tailor their care to individual patients. At every visit, patients could be asked to grade the endometriosis care (on a scale of 0–10) to easily investigate patient-centeredness. When there is more time, women with endometriosis should be asked to complete the entire ECQ to investigate patient-centeredness in depth.

STUDY FUNDING/COMPETING INTEREST(S)

The department of reproductive medicine (involving C.B.L. and V.M.) of the Amsterdam UMC, Vrije Universiteit Amsterdam has received several research and educational grants from Guerbet, Merck and Ferring. The authors have no conflict of interest related to this manuscript.

Towards more patient-centred endometriosis care: a cross-sectional survey using the ENDOCARE questionnaire

STUDY QUESTION

What is the performance of the patient-centredness of endometriosis care in a secondary and a tertiary care setting and how can it be improved?

SUMMARY ANSWER

Overall, patient-centredness was comparable in the two endometriosis care centres, but differed regarding ‘physical comfort’ and ‘continuity and transition’; both centres can learn how to improve several of their targets from the other’s strengths.

WHAT IS KNOWN ALREADY

The ENDOCARE questionnaire (ECQ) is a validated questionnaire for assessing the important quality dimension ‘patient-centredness’. Patient-centredness is associated with quality of life, although this should be explored further by larger-scale studies.

STUDY DESIGN, SIZE, DURATION

A cross-sectional survey, relying on the ECQ, was performed (during 2015 and 2016) among 407 women with surgically diagnosed endometriosis.

PARTICIPANTS/MATERIALS, SETTING, METHODS

This study was conducted in a secondary and a tertiary care centre in the Netherlands. A total of 209 Dutch-speaking women who had endometriosis surgery (2013–2014), completed the ECQ after a postal invitation and, if needed, postal reminders. The assessed outcomes were: overall patient-centredness, the patient-centredness for each of its 10 dimensions, and the patient-centred strengths and targets for improvement. Case-mix adjusted patient-centredness scores (PCS) were compared and strengths and targets for improvement were identified with a matrix modelling importance against experience. The need to improve the targets was quantified with quality impact indices.

MAIN RESULTS AND THE ROLE OF CHANCE

No difference was demonstrated between the overall PCS of the secondary and tertiary centres (respectively: 4.8 and 4.5; P = 0.15). No difference was found in PCS per dimension between the two clinics except for the secondary care centre performing better regarding ‘physical comfort’ (respectively: 4.5 and 3.0; P = 0.01) and ‘continuity and transition’ (respectively: 6.0 and 4.2; P = 0.01). The two centres had nine targets for improvement in common. The secondary and tertiary centres, respectively, had five and seven additional centre-specific targets for improvement. Cross-centre learning is encouraged as 9 out the 12 additional centre-specific targets were strengths in the other centre. The main improvement targets were being able to contact the centre in case of emergency (both centres), the involvement of a significant other (secondary centre), diagnostic delay (secondary centre), personal follow-up (tertiary centre) and disclosing the level of competence of healthcare providers (tertiary centre).

LIMITATIONS, REASON FOR CAUTION

Responders did not differ from non-responders in their stage of endometriosis, educational level, rating of endometriosis care and degree to which their complaints are suppressed. Endometriosis is a chronic condition and patient-centredness might be experienced differently at other points of the endometriosis care trajectory.

WIDER IMPLICATION OF THE FINDINGS

The ECQ is a useful tool to assess patient-centredness in both secondary and tertiary care centres. Further research should focus on how to improve endometriosis care.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was used. V.M. and C.B.L. report grants from Guerbet, grants from Merck and grants from Ferring outside the submitted work. All authors declare that they have no competing interests concerning this publication.

In vitro antiprotozoal activity and cytotoxicity of extracts and isolated constituents from Greenwayodendron suaveolens

ETHNOPHARMACOLOGICAL RELEVANCE

The Nkundo people (Nkundo area of Bolongo, Mai-Ndombe district, Bandundu Province, DR Congo) use various plant parts of the tree Greenwayodendron suaveolens (Engl. & Diels) Verdc. (syn. Polyalthia suaveolens Engl. & Diels) (Annonaceae) against malaria, but its antiprotozoal constituents are not known.

MATERIALS AND METHODS

The crude 80% ethanol extract from the fruits, leaves, root bark and stem bark and 16 fractions were assessed in vitro for their antiprotozoal activity against Trypanosoma brucei brucei, T. cruzi, Leishmania infantum and the chloroquine and pyrimethamine-resistant K1 strain of Plasmodium falciparum (Pf-K1). Their cytotoxic effects were evaluated against MRC-5 cells. Active constituents were isolated by chromatographic means, identified using spectroscopic methods, and evaluated in the same assays.

RESULTS

The root bark extract showed the highest activity against P. falciparum K1 (IC₅₀ 0.26µg/mL) along with the stem bark alkaloid fraction (IC₅₀ 0.27µg/mL). The root bark alkaloid fraction had a pronounced activity against all selected protozoa with IC₅₀ values <1µg/mL. The 90% methanol fractions of the different plant parts showed a pronounced activity against P. falciparum K1, with IC₅₀ values ranging between 0.36µg/mL and 0.69µg/mL. Four constituents were isolated: the triterpenes polycarpol, and dihydropolycarpol, the latter one being reported for the first time from nature, and the alkaloids polyalthenol and N-acetyl-polyveoline. They were active to a various degree against one or more protozoa, mostly accompanied by cytotoxicity. The highest selectivity was observed for N-acetyl-polyveoline against P. falciparum K1 (IC50 2.8µM, selectivity index 10.9).

CONCLUSIONS

These results may explain at least in part the traditional use of this plant species against parasitic diseases such as malaria in DR Congo.

Safety assessment of a traditionally used extract from leaves of Boldoa purpurascens

ETHNOPHARMACOLOGICAL RELEVANCE

Boldoa purpurascens Cav. (Nyctaginaceae) is a plant species used in traditional medicine in Cuba as a diuretic.

AIM OF THE STUDY

The aim of the present investigation was to evaluate the safety profile of a hydroalcoholic extract from leaves of Boldoa purpurascens.

MATERIALS AND METHODS

First, an experimental study to assess the oral acute toxicity at a dose of 2000mg/kg body weight of the extract was carried out. Potential genotoxicity of the extract was evaluated using the Ames test and the micronucleus induction assay in mouse bone marrow. In the Ames test a concentration range of 50, 100, 150, 300 and 500µg/plate was tested. In the micronucleus induction assay, doses of 500, 1000 and 2000mg/kg of body weight were tested. For completeness, since the extract contains saponins, the evaluation of the hemolytic activity, ocular and skin irritation were included.

RESULTS

No signs or symptoms of toxicity were observed in the oral acute toxicity test (body weight at baseline, seven days and end of the experiment of 236.41±20.07, 256.81±30.44 and 240.02±26.16 respectively for the treated group). The hydroalcoholic extract from the leaves was not mutagenic in the Ames test, and no genotoxicity was observed in the micronucleus assay. A hemolysis test at concentration of 1mg/mL confirmed hemolytic activity, which is not a safety concern since saponins are not absorbed after oral administration. In order to evaluate the percentage of protein denaturation, the ocular irritability index was calculated. The extract was found to be irritating. Finally, skin irritability was evaluated and the irritation index was equal to zero.

CONCLUSIONS

Based on the toxicological evaluation of a traditionally used hydroalcoholic extract from the leaves of Boldoa purpurascens we can confirm the safety of its oral use.

Headspace-gas chromatographic fingerprints to discriminate and classify counterfeit medicines

Counterfeit medicines are a global threat to public health. These pharmaceuticals are not subjected to quality control and therefore their safety, quality and efficacy cannot be guaranteed. Today, the safety evaluation of counterfeit medicines is mainly based on the identification and quantification of the active substances present. However, the analysis of potential toxic secondary components, like residual solvents, becomes more important. Assessment of residual solvent content and chemometric analysis of fingerprints might be useful in the discrimination between genuine and counterfeit pharmaceuticals. Moreover, the fingerprint approach might also contribute in the evaluation of the health risks different types of counterfeit medicines pose. In this study a number of genuine and counterfeit Viagra(®) and Cialis(®) samples were analyzed for residual solvent content using headspace-GC-MS. The obtained chromatograms were used as fingerprints and analyzed using different chemometric techniques: Principal Component Analysis, Projection Pursuit, Classification and Regression Trees and Soft Independent Modelling of Class Analogy. It was tested whether these techniques can distinguish genuine pharmaceuticals from counterfeit ones and if distinct types of counterfeits could be differentiated based on health risks. This chemometric analysis showed that for both data sets PCA clearly discriminated between genuine and counterfeit drugs, and SIMCA generated the best predictive models. This technique not only resulted in a 100% correct classification rate for the discrimination between genuine and counterfeit medicines, the classification of the counterfeit samples was also superior compared to CART. This study shows that chemometric analysis of headspace-GC impurity fingerprints allows to distinguish between genuine and counterfeit medicines and to differentiate between groups of counterfeit products based on the public health risks they pose.

In vitro and in vivo antimalarial activity and cytotoxicity of extracts and fractions from the leaves, root-bark and stem-bark of Triclisia gilletii

ETHNOPHARMACOLOGICAL RELEVANCE

To evaluate the in vitro antiplasmodial activity and cytotoxicity, and the in vivo activity of extracts and fractions from the leaves, root-bark and stem-bark of Triclisia gilletii (De Wild) Staner (Menispermaceae), used in traditional medicine against malaria.

MATERIALS AND METHODS

The aqueous and 80% MeOH extracts, and a series of fractions and subfractions from the leaves, stem and root-bark of Triclisia gilletii were tested in vitro for their antiplasmodial activity against a Congolese-sensitive strain of Plasmodium falciparum, against the chloroquine and pyrimethamine-resistant K1 strain of Plasmodium falciparum, for cytotoxicity against MRC-5 cells, and in vivo in mice infected with Plasmodium berghei berghei.

RESULTS

Many samples from the three plant parts exhibited pronounced activity against the Congolese chloroquine-sensitive strain of Plasmodium falciparum with some IC50 values <0.02 µg/ml, and against the K1 strain, with some IC50 <0.25; the selectivity was higher against the Congolese strain. At oral doses of 200 and 400mg/kg body weight in infected mice, the aqueous, 80% methanol and total alkaloid extracts from the three plant parts produced more than 65% and 75% chemosuppression, respectively. The antiplasmodial activity of these three plant parts of Triclisia gilletii can at least in part be attributed to bisbenzylisoquinoline alkaloids, and supports its use for the treatment of uncomplicated malaria in traditional medicine.

Antimalarial activities and toxicities of three plants used as traditional remedies for malaria in the Democratic Republic of Congo:Croton mubango , Nauclea pobeguiniiandPyrenacantha staudtii

The antimalarial activities of crude extracts and 17 fractions from the partition of 80%-methanolic extracts of three plants (the stem bark of Croton mubango, the stem bark of Nauclea pobeguinii and the leaves of Pyrenacantha staudtii) used as antimalarial remedies in the Democratic Republic of Congo were studied both in vitro (against Plasmodium falciparum) and in mice infected with Pl. berghei berghei. The toxic effects of dried aqueous extracts of the plants were also investigated, in uninfected mice. The most active crude extracts in vitro, with median inhibitory concentrations (IC(50)) of <1 microg/ml, were found to be the methanolic and dichloromethane extracts of C. mubango, and the dichloromethane extracts of N. pobeguinii and Py. staudtii. The aqueous extract with the most antimalarial activity in vitro was that of C. mubango (IC(50) = 3.2 microg/ml), followed by that of N. probeguinii (IC(50) = 5.3 microg/ml) and then that of Py. staudii (IC(50) = 15.2 microg/ml). Results from the in-vivo tests of antimalarial activity showed that, at a daily oral dose of 200 mg/kg, all the dichloromethane extracts, the petroleum-ether, chloroformic, ethyl-acetate and residual water-soluble fractions from C. mubango, and the chloroformic, ethyl-acetate and n-butanolic fractions from Py. staudtii produced >80% chemosuppression of the parasitaemias by day 4. The aqueous extracts of C. mubango and N. probeguinii produced a slightly lower but still significant inhibition of parasitaemia (60%-80%) whereas that of Py. staudtii only suppressed the day-4 parasitaemias by 37%. The dried aqueous extract of the stem bark of C. mubango showed some signs of toxicity in mice, with median lethal doses (LD(50)) of 350 mg/kg in the female mice and 900 mg/kg in the male. The extract significantly increased the serum concentrations of glutamate-oxaloacetate transaminase (GOT) and glutamate-pyruvate transaminase (GPT) in mice of both sexes, but had no effect on the blood levels of creatinine or urea. No significant toxic effect was observed for the dried aqueous extracts of N. pobeguinii and Py. staudtii (LD(50) >5 g/kg). Neither of these extracts affected the serum concentrations of GPT or the blood concentrations of creatinine and urea, although the N. pobeguinii extract did increase the serum concentration of GOT.

Antiprotozoal screening and cytotoxicity of extracts and fractions from the leaves, stem bark and root bark of Alstonia congensis

ETHNOPHARMACOLOGICAL RELEVANCE

To evaluate the antiprotozoal activity and cytotoxicity of extracts and fractions from the leaves, root bark and stem bark of Alstonia congensis (Apocynaceae), used in traditional medicine against parasitic diseases.

MATERIALS AND METHODS

The aqueous and 80% MeOH extracts, and a series of fractions and subfractions from the leaves, stem and root bark of Alstonia congensis were tested in vitro for their antiprotozoal activity against Trypanosoma brucei brucei, Trypanosoma cruzi, Lesihamania infantum and the chloroquine and pyrimethamine-resistant K1 strain of Plasmodium falciparum. Their cytotoxicity on MRC-5 cells (human lung fibroblasts) was evaluated as well.

RESULTS

The aqueous and 80% MeOH extracts and a series of subfractions of each plant part exhibited pronounced antiprotozoal activity against the K1 strain of Plasmodium falciparum with IC50 values ranging from 2 to 5 µg/ml, and good activity against Trypanosoma brucei brucei and Trypanosoma cruzi with IC50 values ranging between 5 and 10 µg/ml. The residual 80% MeOH extract from the leaves, and the total alkaloid extract from stem and root bark were the only subfractions active against Leishmania infantum with IC50 values <10 µg/ml. None of the samples from the root bark was cytotoxic against MRC-cell lines (CC50>64 µg/ml). In general, the aqueous extract (traditional decoction) showed the highest selectivity, especially against Plasmodium falciparum.

CONCLUSION

These results can partly support and justify the traditional use of these plant parts of Alstonina congensis as raw materials for the preparation of traditional remedies to treat parasitic diseases such as malaria and trypanosomiasis.

Assessment of the antidiarrhoeal properties of the aqueous extract, the 80% methanol extract and its soluble fractions of the leaves of Alstonia congensis Engl. (Apocynaceae) in Wistar rats

AIM OF THE STUDY

To evaluate the antidiarrhoeal properties of Alstonia congensis leaves claimed to be effective for the treatment of diarrhoea by traditional healers during our ethnopharmacological investigation conducted in Kinshasa, Democratic Republic of Congo.

MATERIALS AND METHODS

The aqueous extract (decoction), and the 80% hot methanol extract (Soxhlet extraction) were obtained. This last extract was fractionated. The antidiarrhoeal activity was evaluated using castor oil and magnesium sulphate-induced diarrhoea in animals. The potential antibacterial activity of all samples was also assessed in vitro.

RESULTS

At all oral doses of 100 and 200 mg/kg body weight, all A. congensis samples showed significant and dose-dependent antidiarrhoeal activity in treated Wistar rats characterised by significant increase of onset time and decrease of all other diarrhoeal parameters at various degrees compared to untreated groups in both models. At the highest oral dose of 200 mg/kg bodyweight, the 80% hot methanol and aqueous extracts produced 79.8 ± 2.1% and 78.6 ± 0.5%, and 75.0 ± 2.1% and 71.4 ± 2.1% inhibition of defecation and diarrhoea respectively against castor oil-induced diarrhoea, and 75.0 ± 1.2% and 73.3±1.2% inhibition of diarrhoea respectively against magnesium sulphate-induced diarrhoea. The 80% hot methanol and aqueous detannified extracts showed low activity (42-47% inhibition of defecation and/or diarrhoea in both tests) suggesting that tannins may be responsible for the observed activity. At the same oral doses, the total alkaloid extract, the chloroform soluble fraction rich in alkaloids, the 80% methanol and the alkaline aqueous soluble subfractions produced more than 50% inhibition of defecation and/or diarrhoea in both tests. From the antibacterial testing in vitro, results indicated that all A. congensis samples exhibited an antibacterial activity mainly against bacteria implicated in diarrhoea with MIC and MBC values in the range of 15.6-500 μg/ml. The most active samples were the aqueous (decoction) and the 80% hot methanol dried extracts, the chloroform subfraction rich in alkaloids and the total alkaloid extract (MIC: 15.7-125 μg/ml, MBC: 31.2-250 μg/ml). Proteus varibilis was found to be the most resistant microorganism.

CONCLUSION

These reported results can partly support and justify the traditional use of extracts from Alstonia congensis leaves for the treatment of diarrhoea in tradittional medicine.

In vitro antiprotozoal and cytotoxic activity of 33 ethonopharmacologically selected medicinal plants from Democratic Republic of Congo

ETHNOPHARMACOLOGICAL RELEVANCE

The antiprotozoal and cytotoxic activity of the aqueous extracts from 33 medicinal plants, used by traditional healers for the treatment of various parasitic diseases and collected after an ethnopharmacological inventory conducted in the Bolongo area, Bandundu province in DR Congo, was evaluated.

MATERIALS AND METHODS

Decoctions were prepared, lyophilized and evaluated for in vitro antiprotozoal activity against Trypanosoma b. brucei, Trypanosoma cruzi, Leishmania infantum, and the chloroquine- and pyrimethamine-resistant K1 strain of Plasmodium falciparum. Cytotoxicity against MRC-5 cells was included to assess selectivity of activity.

RESULTS

Most of the tested extracts exhibited pronounced (IC(50)≤5μg/ml) or good (5<IC(50)≤10μg/ml) antiprotozoal activity against one or more of the selected protozoa. A total of 19 plant extracts inhibited Trypanosoma b. brucei, especially the extract from Isolona hexaloba stem bark (IC(50)=1.95μg/ml, SI=16.5); 8 plant extracts were active against Trypanosoma cruzi, the extracts from Enanatia chlorantha stem bark and Quassia africana root bark being the most active with IC(50) values of 1.87 and 1.88μg/ml, respectively (SI=3.0 and 3.3, respectively); 8 plant extracts showed activity against Leishmania infantum, with extracts from Napoleona vogelii stem bark and Quassia africana root bark as the most active with IC(50) values of 5.66 and 5.04μg/ml (SI=11.3 and 1.2). Finally, 9 plant extracts inhibited Plasmodium falciparum K1 with the extracts from Quassia africana (root bark and stem bark) being the most active ones with IC(50) values of 0.46 and 1.27μg/ml (SI=13.7 and 13.6). Extracts from Enantia chlorantha stem bark, Piptadeniastrum africanum stem bark and Quassia africana root bark were cytotoxic for MRC-5 cells (CC(50)<10μg/ml).

CONCLUSIONS

These results can partly support and justify the traditional use of some of these plant species for the treatment of parasitic diseases.

Intracellular drug delivery in Leishmania-infected macrophages: Evaluation of saponin-loaded PLGA nanoparticles

Drug delivery systems present an opportunity to potentiate the therapeutic effect of antileishmanial drugs. Colloidal carriers are rapidly cleared by the phagocytic cells of the reticuloendothelial system (RES), rendering them ideal vehicles for passive targeting of antileishmanials. This paper describes the development of poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles (NPs) for the antileishmanial saponin β-aescin. NPs were prepared using the combined emulsification solvent evaporation/salting-out technique. Confocal microscopy was used to visualise the internalisation and intracellular trafficking of fluorescein- and nile red-labelled PLGA NPs in J774A.1 macrophages infected with GFP-transfected Leishmania donovani. The in vitro activity of aescin and aescin-loaded NPs on L. infantum was determined in the axenic model as well as in the ex vivo model. The developed PLGA NPs were monodispersed with Z(ave)<300 nm, exhibited negative zeta potentials and had relatively high drug loadings ranging from 5.80 to 8.68% w/w PLGA. The fluorescent NPs were internalised by the macrophages and trafficked towards the lysosomes after 2 h in vitro incubation. Co-localisation of the NPs and the parasite was not shown. A two-fold increase in activity was observed in the ex vivo macrophage model by encapsulating β-aescin in PLGA NPs (IC(50), 0.48-0.76 µg/mL vs. 1.55 ± 0.32 µg/mL for the free drug).

Radical scavenging and xanthine oxidase inhibitory activity of phenolic compounds from Bridelia ferruginea stem bark

Bridelia ferruginea Benth. (Euphorbiaceae) is a subtropical medicinal plant widely used in traditional African medicine against various diseases, including rheumatic pains. Seven of its constituents (3-O-methylquercetin (1), 3,7,3′,4′-tetra-O-methylquercetin (rutisin, 2), myricetin (3), 3′,4′,5′-tri-O-methylmyricetin (ferrugin, 4), 3,3′,4′,5′-tetra-O-methylmyricetin (5), quercetin 3-O-glucoside (6), and a biflavanol gallocatechin-[4′-O-7]-epigallocatechin (7)) have been evaluated in-vitro in the xanthine-xanthine oxidase enzymatic system for inhibition of xanthine oxidase and radical scavenging activity. Results indicated that compounds 1, 3, 4 and 6 exhibited, at different levels, xanthine oxidase inhibiting and superoxide scavenging activity at micromolar concentrations, whereas compound 7 showed scavenging activity only. Compounds 2 and 5 were inactive in both cases. Study of the structure-activity relationship demonstrated that for flavonoids the xanthine oxidase inhibitory activity was reduced by methylation of the hydroxyl functionality at C-3 and in rings A and B. These results may partly explain and support the use of B. ferruginea stem bark for the treatment of rheumatic pains in traditional medicine.

The spasmolytic activity of extracts and some isolated compounds from the leaves of Morinda morindoides (Baker) Milne-Redh. (Rubiaceae)

AIM

The study was aimed to evaluate the in vitro antispasmodic activity of Morinda morindoides leaves aqueous extract, its soluble fractions and isolated compounds to provide the pharmacological basis for its use for the treatment of constipation and diarrhoea in traditional medicine.

METHODS

The antispasmodic activity of each sample was evaluated on acetylcholine (ACh) and the depolarized KCl solution induced contractions on guinea-pig isolated ileum suspended in Tyrode's solution.

RESULTS

At a test concentration of 40mug/ml in organ bath, the aqueous extract and its petroleum ether soluble fraction showed a spasmogenic effect on both agonists. The diethylether, ethyl acetate, n-butanol and residual aqueous phase soluble fractions from the partition of the aqueous extract exhibited spasmolytic activity producing 47-100% inhibition of contractions induced by both agonists with IC(50) values ranged from 6 to 15 microg/ml according to the case. In addition, the n-butanol and residual aqueous phase soluble fractions showed an inhibitory effect of 75 and 66% respectively on low high [K(+)] (25 mM) and 65 and 60% respectively on high [K+] (80 mM). Crude flavonoids showed spasmolytic on both agonists while crude saponins only showed spasmolytic activity on ACh and displayed spasmogenic effect on KCl. Quercetin, quercitrin and rutin exhibited significant antispasmodic effect with IC(50) values <0.1 microg/ml. Epoxygaertneroside and gaertneroside showed good antispasmodic activity on both agonists (4<IC(50)<7 microg/ml).

CONCLUSION

Morinda morindoides leaves possess spasmogenic and spasmolytic properties that can at least explain and support its traditional use against constipation and diarrhoea respectively.

Antiprotozoal and cytotoxic screening of 45 plant extracts from Democratic Republic of Congo

AIM OF THE STUDY

To evaluate in vitro the antiprotozoal and cytotoxic activities of 80% methanol extract from 45 medicinal plants collected in Sankuru (Democratic Republic of Congo) against Trypanosoma brucei brucei, Trypanosoma cruzi and the chloroquine-sensitive Ghanaian strain of Plasmodium falciparum, and MRC-5 cell lines respectively.

MATERIAL AND METHODS

Different extracts were obtained by maceration of each plant part used with 80% methanol for 24h. The mixture was filtered and evaporated in vacuo to give corresponding dried extract. The activity against Trypanosoma brucei brucei and Trypanosoma cruzi were performed in 96 well tissue plates each containing 10 microl aqueous plant extract dilutions (100 to 0.01 microg/ml) with 10 microl of the parasite suspension cultured in Hirumi medium supplemented with 10% foetal calf serum, a solution of 2% penicillin/streptomycin (2% P/S) After 4 days incubation with Almar blueâ solution, fluorescence was measured at 500 nm emission and 530 nm excitation and results expressed as percentage reduction in parasite compared to control wells. The antiplasmodial activity of was assessed in vitro against the chloroquine-sensitive Ghanaian strain of Plasmodium falciparum cultured in RPMI-1640 medium by the lactate deshydrogenase assay in the presence of plant extracts (50 to 0.01 microg/ml). Cell-lines MRC-5 were cultured in MEM medium supplemented with 20mM l-glutamine, 16.5mM NaHCO(3), 5% foetal calf serum and 2% P/S solution. After 4h incubation, cell proliferation/viability was spectrophotomecally assessed at 540 nm after addition of MTT. In each assay, the IC50 value for each sample was derived by the drug concentration-response curves.

RESULTS

The extracts from Alcornea cordifolia leaves, Momordica charantia whole plant, Omphalocarpum glomerata, root bark and Piptadia africanum stem bark showed good antiprotozoal activity against Trypanosoma brucei brucei with IC50 values from 0.7 to 7 microg/ml. Only Piptadenia africanum extract showed a pronounced antiprotozoal activity against Trypanosoma cruzi (IC50=4.0+/-06 microg/ml). The extracts from Alchornea cordifolia, Polyathia swaveleons stem bark, Sapium cornutum stem bark and Triclisia giletii stem bark exhibited a pronounced antiplasmodial activity against P. falciparum Ghanaian strain with IC50 values ranging from 0.5 to 3.0 microg/ml. Piptadenia africanum extract was the most cytotoxic sample (CC50=0.25 microg/ml) with poor selectivity against all selected protozoa (SI<10) while other active extracts did not show a significant cytotoxic effect against MCR-5 cell-lines with good selectivity according to the case.

CONCLUSION

These active plant extracts are selected for extensive studies leading to the isolation of active constituents.

1,2,3-Triazolylalkylribitol derivatives as nucleoside hydrolase inhibitors

A range of novel 1,2,3-triazolylalkylribitol derivatives were synthesized and evaluated as nucleoside hydrolase inhibitors. The most active compound (11a) has low micromolar potency and is structurally diverse from previously reported nucleoside hydrolase inhibitors, which, along with the simplicity of the chemistry involved in its synthesis, makes it a good lead for the further development of novel nucleoside hydrolase inhibitors.

Cytotoxicity and in vitro susceptibility of Entamoeba histolytica to Morinda morindoides leaf extracts and its isolated constituents

An aqueous decotion (dried extract), an 80% MeOH extract from Morinda morindoides leaves, and 10 flavonoids and 4 iridoids isolated from the 80% MeOH extract were evaluated in vitro for their potential antiamoebic activity and their cytotoxic effect against MT-4 cells. Results indicated that the aqueous decoction and the 80% MeOH extract exhibited an interesting antiamoebic activity with IC(50) values of 3.1 +/- 1.7 and 1.7 +/- 0.6 microg/ml, respectively. Apigenin-7-O-glucoside and luteolin-7-O-glucoside exhibited a moderate antiamoebic activity with IC(50) values of 22.3 +/- 3.2 and 37.4 +/- 2.7 microg/ml, respectively. Kaempferol (IC(50) = 10.3 +/- 2.3 microg/ml), apigenin (IC(50) = 12.7 +/- 4.3 microg/ml), and luteolin (IC(50) = 17.8 +/- 4.3 microg/ml) showed a more pronounced activity than their corresponding glycosides. All tested iridoids displayed a very good activity with IC(50) values less than 10 microg/ml. The most active iridoids were epoxygaertneroside (IC(50) = 1.3 +/- 0.4 microg/ml) and methoxygaertneroside (IC(50) = 2.3. +/- 0.7), followed by gaertneroside and gaertneric acid with IC(50) values of 4.3 +/- 1.8 and 7.1 +/- 1.4 microg/ml, respectively. Except quercetin and quercetin-7,4'-dimethylether which have shown a cytotoxic effect with IC(50) ranging from 14 to 22 microg/ml. No correlation could be deduced between the observed antiamoebic and cytotoxic activity of these tested samples. A structure-activity relationship for isolated compounds is discussed. These findings support the medicinal report for the traditional use of Morinda morindoides leaves for the treatment of amoebiasis.

Biologically active bisbenzylisoquinoline alkaloids from the root bark of Epinetrum villosum

Methanol and water extracts of the root of Epinetrum villosum (Exell) Troupin (Menispermaceae) were found to exhibit antimicrobial and antiplasmodial activities. Investigation of the active methanol fraction led to the isolation of four bisbenzylisoquinoline alkaloids, i.e., cycleanine, cycleanine N-oxide, isochondodendrine and cocsoline. Structures were established by spectroscopic methods. Cocsoline displayed antibacterial and antifungal activities (MIC values of 1000-15.62 and 31.25 microg/ml, respectively). Isochondodendrine was found to have the most potent antiplasmodial activity (IC50 = 0.10 microg/ml), whereas the IC50 on HCT-116 human colon carcinoma cells was 17.5 microg/ml (selectivity index 175). Cycleanine acted against HIV-2 (EC50=1.83 microg/ml) but was at least 10-fold less active against HIV-1. Cycleanine N-oxide showed no activity towards all tested microorganisms.

Evaluation of bioactive saponins and triterpenoidal aglycons for their binding properties on human endothelin ETA and angiotensin AT1 receptors

Different types of triterpenes including saponins and aglycons were evaluated for their ability to inhibit [3H] BQ-123 and [3H] angiotensin II binding to the human endothelin 1 ETA and angiotensin II AT1 receptors, respectively. Selectivity for only one of the two receptors was exhibited by asiatic acid and its saponins (ETA) and oleanolic acid (AT1). To a lesser extent betulinic acid, beta-amyrin and friedelin also showed selectivity for the ETA receptor. To address the question whether the effect of saponins on cell membranes might interfere with the normal binding of specific radioligands to their receptors, the activity of saponins with different haemolytic properties were compared. Highly haemolytic saponins such as alpha-hederin and beta-escine showed partial (60%) inhibition of radioligand-binding to the ETA receptor and complete inhibition (100%) to the AT1 receptor. Moreover, the haemolytically inactive kryptoescine, at the same concentration, caused complete inhibiton of radioligand-binding to both receptors, indicating that inhibition of receptor binding was not related to the membrane-interacting properties of saponins.

In vitro antiplasmodial activity of callus culture extracts and fractions from fresh apical stems of Phyllanthus niruri L. (Euphorbiaceae): part 2

The ethanolic extracts from fresh apical stems of Phyllanthus niruri L. (Euphorbiaceae) cultured on Murashige and Skoog (MS) medium supplemented with IBA/BAP/Coco nucifera L. milk for 1, 2, 4 and 6 months were phytochemically and biologically investigated and compared with intact plant part and whole plant extracts. Results from the in vitro antiplasmodial testing indicated that the EtOH extract of a 1-month-old callus culture (IC(50) = 16.3 +/- 2.5 microg/ml) exhibited a higher activity than the ethanolic extracts of the fresh apical stem (IC(50) = 18.2 +/- 2.4 microg/ml) and callus cultures of 2-, 4- and 6-months-old (25 microg/ml < IC(50) < 40 microg/ml). These activities were however lower than that displayed by the ethanolic extract of the whole plant (IC(50) < 3 microg/ml). The EtOH extract of 1-month-old callus culture (the most active) was fractionated with solvents of different polarities. Its CH(2)Cl(2) fraction rich in terpenic constituents (IC(50) = 9.2 +/- 3.4 microg/ml) exhibited a higher antiplasmodial activity than its isoamylic alcohol fraction obtained at pH 2-3 (IC(50) = 25.6 +/- 2.3 microg/ml) rich in flavonoids. The activity of these two fractions was lower than that displayed by the same fractions from the whole plant (2 microg/ml < IC(50) < 3 microg/ml). Alkaloidic fractions from the whole plant and 1-month-old callus culture of fresh apical stem were considered as inactive (IC(50) > 100 microg/ml).

Proanthocyanidins in health care: current and new trends

Polyphenolic compounds are widely distributed in higher plants and are an integral part of the human diet. Recent interest in these substances has been stimulated by their potential health benefits, which are believed to arise mainly from their antioxidant activity. In the past years, the antioxidant activity of flavonoids has been studied in detail. An important but often overlooked group of polyphenols is that of the proanthocyanidins. Therefore, the present review is focused mainly on the antioxidant activity of proanthocyanidins and its relevancy in vivo. The three most important mechanisms of their antioxidant action will be discussed, i.e. free radical scavenging activity, chelation of transition metals, and inhibition of enzymes. In addition, the protective role of proanthocyanidins against lipid peroxidation and peroxynitrite, as well as their antimicrobial properties will be discussed. To study the in vivo relevancy of the proanthocyanidin activities, the knowledge of their pharmacokinetic parameters is crucial. Although bioavailability and metabolism data on polyphenols in general and proanthocyanidins in particular are still largely unavailable, the first reports indicate that at least monomers and smaller oligomeric procyanidins are absorbed. There is also considerable scientific and public interest in the important role that antioxidants may play in health care, e.g. by acting as cancer chemopreventive and anti-inflammatory agents and by reducing risk of cardiovascular mortality. Each of these aspects will be discussed, with special attention to the role of proanthocyanidins on apoptosis, gene expression and transcription factors, such as NF-kappa B.

In vitro antiplasmodial activity of extracts and fractions from seven medicinal plants used in the Democratic Republic of Congo

The in vitro antiplasmodial activity of seven EtOH extracts and twenty fractions from the partition of the initial ethanolic extracts from seven African medicinal plants used in the Democratic Republic of Congo (DR Congo) for the treatment of malaria was evaluated. The most active EtOH extracts (IC50 < 3 microg/ml) were those from Cassia occidentalis leaves, Euphorbia hirta whole plant, Garcinia kola stem bark and Phyllanthus niruri whole plant. Their respective petroleum ether soluble fractions also exhibited an antiplasmodial activity with IC50 < 3 microg/ml. EtOH extracts from Vernonia amygdalina leaves (5 < IC50 < 10 microg/ml), Tetracera poggei leaves (10 < IC50 < 50 microg/ml) and Morinda morindoides leaves (50 < IC50 < 100 microg/ml) were less active, but their petroleum ether fractions exhibited a pronounced antiplasmodial activity (IC50 < 3 microg/ml). The same observation could also be made for the petroleum ether fraction from Cassia occidentalis, Euphorbia hirta, Garcinia kola and Phyllanthus niruri. Isoamyl alcohol fractions from Euphorbia hirta, Phyllanthus niruri and Vernonia amygdalina showed IC50) values less than 3 microg/ml, and from Cassia occidentalis, Garcinia kola, Morinda morindoides and Tetracera poggei between 10 and 50 microg/ml. The observed antiplasmodial activity may be related to the presence of terpenes, steroids, coumarins, flavonoids, phenolic acids, lignans, xanthones and anthraquinones.

Correlation between chemical composition and antibacterial activity of essential oils of some aromatic medicinal plants growing in the Democratic Republic of Congo

The chemical composition of essential oils from 15 aromatic medicinal plant species growing in the Democratic Republic of Congo have been studied. More than 15 constituents in an amount higher than 0.1% were identified in each essential oil. 1,8-cineole, alpha and beta-pinene, p-cymene, myrcene, gamma-terpinene, alpha-terpineol and limonene were prevalent constituents in almost more than 10 selected plant species. Results from the antibacterial testing by the diffusion method indicate that all essential oils (5 microl per disc) inhibited the growth of selected bacteria at different extents. The most active antibacterial essential oils were those of the leaves of Eucalyptus camadulensis and Eucalyptus terticornis (12-30 mm zone diameter of inhibition). They showed particularly a most potent inhibition of Pseudomonas aeruginosa growth (15-16 mm), followed by Eucalyptus robusta (12 mm). Essential oils from the leaves of Eucalyptus alba, Eucalyptus citriodora, Eucalyptus deglupta, Eucalyptus globulus, Eucalyptus saligna, Eucalyptus robusta, Aframomum stipulatum, Cymbopogon citratus, Ocimum americanum and that of the seeds of Monodora myristica showed also a good antibacterial activity (10-18 mm). Eucalyptus propinqua, Eucalyptus urophylla and Ocimum gratissimum essential oils were the less active samples against the selected bacteria. No correlation between the amount of major constituents such as 1,8-cineol, alpha-pinene, p-cymene, cryptone or thymol and the antibacterial activity was observed.

Further evaluation of Rwandan medicinal plant extracts for their antimicrobial and antiviral activities

A total of 45 Rwandan plant extracts, belonging to 37 different plant species out of 21 families, were investigated for their antibacterial, antifungal, and antiviral properties. The plants were selected on the base of their ethnomedicinal use against infections and autoimmune diseases. From all the plant extracts tested, only Clematis hirsuta (leaves) showed a pronounced antifungal activity against Candida albicans and the dermatophytes Trichophyton rubrum, Epidermophyton floccosum, and Microsporum canis. Seven plant extracts showed a high antiviral activity against the DNA-virus Herpes simplex type 1, while five and three plant extracts were highly active against the RNA-viruses Coxsackie and Polio, respectively. Only Macaranga kilimandscharica (leaves) showed an interesting anti-measles activity, whereas Eriosema montanum (leaves) and Entada abyssinica (leaves) were highly active against Semliki forest virus. Some plant extracts showed an antibacterial activity against Gram-positive bacteria and Mycobacterium fortuitum, but none of them were active against the Gram-negative bacteria tested.

Complement modulating activity of Rwandan medicinal plants

Forty-two ethanolic extracts of thirty-six Rwandan medicinal plants were investigated for their influence on complement-mediated hemolysis. The plants were selected on the base of their ethnomedicinal use in infections and autoimmune diseases. Eight plant extracts showed an inhibitory activity against the classical pathway of the complement system and ten plant extracts against the alternative pathway. Three plant extracts exhibited an interesting activity against both pathways, i.e. Aspilia pluriseta, Coleus kilimandschari, and Macaranga kilimandscharica (leaves and stem). Further study indicated that the complement inhibitory activity was not caused by chelation of bivalent cations or by direct action on the target erythrocytes.

Antiviral activity of Rwandan medicinal plants against human immunodeficiency virus type-1 (HIV-1)

Selected plants used in Rwandan traditional medicine for the treatment of infections and/or rheumatoid diseases were investigated for antiviral activity in vitro against human immunodeficiency virus type-1 (HIV-1). Of the 38 tested 80% ethanolic extracts, belonging to plants of 21 different families only the extracts from the leaves of Aspilia pluriseta (Asteraceae) and Rumex bequaertii (Polygonaceae) had interesting selectivity indices (SI = ratio of the 50% cytotoxic concentration to the 50% effective antiviral concentration) higher than 1. Further fractionation of the initially antivirally inactive ethanolic extract of Tithonia diversifolia, however, led to an aqueous fraction with a high anti-HIV-1 activity (SI > 461), indicating that the cytotoxicity of some plant components may mask the antiviral properties of the active plant substances in total plant extracts.

Chemical and biological investigations on Zizyphus spina-christi L

Different extracts and fractions of the leaves, fruits and seeds of Zizyphus spina-christi L. grown in Egypt were investigated in vitro for their antiviral, antifungal and antibacterial activities. The flavonoids quercetin, hyperoside, rutin and quercetin-3-O-[beta-xylosyl-(1-2)-alpha-rhamnoside] 4'-O-alpha- rhamnoside) were isolated.

Antiviral, haemolytic and molluscicidal activities of triterpenoid saponins from Maesa lanceolata: establishment of structure-activity relationships

Ten saponins isolated from the leaves of Maesa lanceolata were tested for their antiviral, haemolytic and molluscicidal activities. The influence of the substitution pattern of these acylated triterpenoid saponins on their biological activities was investigated and structure-activity relationships were established. Maesasaponin VI(2) (3 beta-O-[[alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-galactopyranosyl-(1 --> 3)]-[beta-D-galactopyranosyl-(1 --> 2)]-beta-D-glucopyranuronyl]-21 beta,22 alpha-diangeloyloxy-13 beta,28-epoxyolean-16 alpha,28 alpha-diol), the most potent molluscicidal compound (LC(50) 0.5 ppm), also showed virucidal and haemolytic activity. In general, 21,22-diacylation appeared to be associated with a virucidal (reduction factor of the viral titer > or = 10(3) at 50 microg/ml) and haemolytic activity (HC(50) < or = 1 microg/ml).

Cycloabyssinone, a new cycloterpene from Harrisonia abyssinica

A new cycloterpene, 4beta,14-dimethyl-9,19-cyclo-5alpha,9beta-ergost-24(28)-en-3-one (cycloabyssinone) (1), and a known terpene, 3-friedelanone, were isolated from stem bark of Harrisonia abyssinica and identified by spectroscopic methods.

Isolation and complete NMR assignment of the numbing principle from Chrysanthemum morifolium

The isolation and the complete 1H and 13C-NMR assignments of the numbing principle [N-isobutyl-6-(2-thienyl)-2E,4E-hexadienamide (1)] from Chrysanthemum morifolium are reported.

In-vivo antimalarial activity of Cassia occidentalis, Morinda morindoides and Phyllanthus niruri

The ethanolic, dichloromethane and lyophilized aqueous extracts of Cassia occidentalis root bark, Morinda morindoides leaves and whole plants of Phyllanthus niruri were evaluated for their antimalarial actvity in vivo, in 4-day, suppressive assays against Plasmodium berghei ANKA in mice. No toxic effect or mortality was observed in mice treated, orally, with any of the extracts as a single dose, of 500 mg/kg body weight, or as the same dose given twice weekly for 4 weeks (to give a total dose of 4 g/kg). No significant lesions were observed, by eye or during histopathological examinations, in the hearts, lungs, spleens, kidneys, livers, large intestines or brains of any mouse. At doses of 200 mg/kg, all the ethanolic and dichloromethane extracts produced significant chemosuppressions of parasitaemia (of > 60% for C. occidentalis root bark and Ph. niruri whole plant, and of 30% for M. morindoides leaves) when administered orally. The most active ethanolic extract, that of Ph. niruri, reduced parasitaemia by 73%. The dichloromethane extracts of M. morindoides and Ph. niruri produced similar reductions (74% and 72% chemosuppression, respectively), whereas that of C. occidentalis was slightly less active (60% chemosuppression). Each lyophilized aqueous extract was less active than the corresponding ethanolic extract.