Plants used to treat epilepsy by Tanzanian traditional healers

Natural product-derived therapies for treating drug-resistant epilepsies: From ethnopharmacology to evidence-based medicine

ETHNOPHARMACOLOGICAL RELEVANCE

Epilepsy is one of the most prevalent neurological human diseases, affecting 1% of the population in all age groups. Despite the availability of over 25 anti-seizure medications (ASMs), which are approved in most industrialized countries, approximately 30% of epilepsy patients still experience seizures that are resistant to these drugs. Since ASMs target only limited number of neurochemical mechanisms, drug-resistant epilepsy (DRE) is not only an unmet medical need, but also a formidable challenge in drug discovery.

AIM

In this review, we examine recently approved epilepsy drugs based on natural product (NP) such as cannabidiol (CBD) and rapamycin, as well as NP-based epilepsy drug candidates still in clinical development, such as huperzine A. We also critically evaluate the therapeutic potential of botanical drugs as polytherapy or adjunct therapy specifically for DRE.

METHODS

Articles related to ethnopharmacological anti-epileptic medicines and NPs in treating all forms of epilepsy were collected from PubMed and Scopus using keywords related to epilepsy, DRE, herbal medicines, and NPs. The database clinicaltrials.gov was used to find ongoing, terminated and planned clinical trials using herbal medicines or NPs in epilepsy treatment.

RESULTS

A comprehensive review on anti-epileptic herbal drugs and natural products from the ethnomedical literature is provided. We discuss the ethnomedical context of recently approved drugs and drug candidates derived from NPs, including CBD, rapamycin, and huperzine A. Recently published studies on natural products with preclinical efficacy in animal models of DRE are summarized. Moreover, we highlight that natural products capable of pharmacologically activating the vagus nerve (VN), such as CBD, may be therapeutically useful to treat DRE.

CONCLUSIONS

The review highlights that herbal drugs utilized in traditional medicine offer a valuable source of potential anti-epileptic drug candidates with novel mechanisms of action, and with clinical promise for the treatment of drug-resistant epilepsy (DRE). Moreover, recently developed NP-based anti-seizure medications (ASMs) indicate the translational potential of metabolites of plant, microbial, fungal and animal origin.

The Beneficial Role of Photobiomodulation in Neurodegenerative Diseases

Photobiomodulation (PBM), also known as Low-level Laser Therapy (LLLT), involves the use of light from a laser or light-emitting diode (LED) in the treatment of various disorders and it has recently gained increasing interest. Progressive neuronal loss with attendant consequences such as cognitive and/or motor decline characterize neurodegenerative diseases. The available therapeutic drugs have only been able to provide symptomatic relief and may also present with some side effects, thus precluding their use in treatment. Recently, there has been an exponential increase in interest and attention in the use of PBM as a therapy in various neurodegenerative diseases in animal studies. Because of the financial and social burden of neurodegenerative diseases on the sufferers and the need for the discovery of potential therapeutic inventions in their management, it is pertinent to examine the beneficial effects of PBM and the various cellular mechanisms by which it modulates neural activity. Here, we highlight the various ways by which PBM may possess beneficial effects on neural activity and has been reported in various neurodegenerative conditions (Alzheimer's disease, Parkinson's disease, epilepsy, TBI, stroke) with the hope that it may serve as an alternative therapy in the management of neurodegenerative diseases because of the biological side effects associated with drugs currently used in the treatment of neurodegenerative diseases.

Beliefs and attitudes of traditional healers regarding epilepsy in Cameroon

INTRODUCTION

People living with epilepsy suffer from stigmatization, overprotection, or exclusion, thus, part of these population in developing countries uses traditional medicine as a first resort.

METHODS

We prospectively conducted a study to determine the knowledge, attitudes, and practices (KAP) of traditional healers (THs) concerning epilepsy. Over a 9-month period, we included 208 THs practicing in the Littoral, Center and West regions of Cameroon who agreed to participate in the study. The THs were interviewed using a standardized questionnaire. Data were analyzed using Epi Info version 7.2 software.

RESULTS

Two-hundred and eight THs were recruited, with a mean age ± standard deviation (SD) of 49.9 ± 11.4 years, and 169 (81.2%) were male. Primary 77(37.0%) and secondary 67(32.2%) levels of education were the most represented, and most of the THs had more than 10 years of professional experience. One hundred and forty-one TH (68,7%) had poor knowledge about epilepsy. The independent factors associated with poor knowledge were female sex, Muslim religion, and marital status of cohabitation. One hundred and eighty-four THs (88.4%) had a good attitude and practices toward people with seizures. Factors independently associated with poor practices and attitude were rural residence, Muslim religion, and education level.

CONCLUSION

Our result confirmed that THs had poor knowledge about epilepsy but good attitudes and practices about epilepsy. THs were in favor of future collaboration with modern medicine in the care of people living with epilepsy.

Traditional health practices: A qualitative inquiry among traditional health practitioners in northern Uganda on becoming a healer, perceived causes of illnesses, and diagnostic approaches

BACKGROUND

The practice of traditional and complementary medicine is increasing in most low-and middle-income countries especially for chronic communicable and non-communicable diseases. In this study, we aimed to understand how people gain healing power and become traditional health practitioners (THPs), perceived causes of illnesses, and how THPs diagnose illnesses.

METHODS

This was a cross-sectional qualitative interview-based study. We used semi-structured in-depth guides to collect data from THPs identified through the Acoli cultural institutions and snowball sampling technique. The study team visited the THPs and interviewed them in their homes. Some THPs allowed the study team to visit them more than once and as well observe their healing practices and medicines. Thematic analysis approach was used to analyze the data. Atlas.ti version 9.2 was used to support data analysis.

RESULTS

Twenty two THPs aged 39-80 years were included in the study. Most of the respondents were male, and married. We identified three main themes: (i) how people gain healing power and become traditional health practitioners; (ii) perceived causes of illnesses; and (iii) how illnesses are diagnosed. The majority of respondents reported that most people become THPs through: inheriting healing power from their parents or grandparents; transfer of healing powers from senior healers; instructions during visions and dreams; and, acquiring healing power during spirits possessions. Perceived causes of illnesses included: fate and natural causes, spirits attacks, curses by elders, witchcraft, contagion and infections, poor hygiene, heredity, and malevolent actions. THPs diagnose illnesses through various approaches including consultations with spirits, observing patterns of occurrences and events, evaluation of symptoms and signs of illnesses, use of bones from animals/birds and other objects to diagnose illnesses, performing diagnostic rituals, and using biomedical laboratory testing in health facilities.

CONCLUSION

Healing knowledge and powers are acquired in particular ways that can be traced to appraise authenticity of healers during registration and licensing to ensure safety of patients. Understanding perspectives of the THPS on causes of illnesses and how diagnoses are made potentially informs strategies for integration and or collaboration between the national biomedical health system and traditional health practices.

Antifungal active ingredient from the twigs and leaves of Clausena lansium Lour. Skeels (Rutaceae)

Two novel amides, named clauphenamides A and B, and twelve other known compounds were isolated from the twigs and leaves of Clausena lansium Lour. Skeels (Rutaceae). Their structures were elucidated on the basis of extensive spectroscopic analysis and comparison with data reported in the literature. Clauphenamide A (1) featured in the unit of N-2-(4,8-dimethoxyfuro [2,3-b]quinolin-7-yl)vinyl, and clauphenamide B (2) was a unprecedented N-phenethyl cinnamide dimer. Other known compounds belong to pyrrolidone amides (3 and 4), furacoumarins (7-10), simple coumarins (11-14), lignan (5) and sesquiterpene (6). Compounds 5, 6, 10 and 12 were separated from the genus (Clausena) for the first time, while 13 was isolated in the species (C. lansium) for the first time. The antifungal activities of the isolated compounds were assayed. As a result, at the concentration of 100 μg/ml, compared with the control (chlorothalonil, inhibition rate of 83.67%), compounds 1 and 2 were found to exhibit moderate antifungal activity against B. dothidea with inhibition rates of 68.39% and 52.05%, respectively. Compounds 11-14 also exhibited moderate activity against B. dothidea and F. oxysporum, with inhibition rates greater than 40%. In addition, compared with the control (chlorothalonil, inhibition rate of 69.02%), compounds 11-14 showed strong antifungal activity to P. oryzae, with inhibition rates greater than 55%. Among them, compound 14 has the strongest antifungal activity against P. oryzae, and the inhibition rate (65.44%) is close to that of the control chlorothalonil. Additionally, the structure-activity relationships of the separated compounds are also discussed preliminarily in this paper.

The traditional uses, phytochemistry and pharmacology of Abrus precatorius L.: A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

Abrus precatorius L. (AP) is a folk medicine with a long-term medicinal history worldwide, which is extensively applied to various ailments, such as bronchitis, jaundice, hepatitis, contraception, tumor, abortion, malaria, etc. Meanwhile, its leaves are also served as tea in China, and its roots are employed as a substitute for Glycyrrhiza uralensis or as a raw material for the extraction of glycyrrhizin in India. Thus, AP is considered to be a plant with dual values of medicine and economy as well as its chemical composition and biological activity, which are of growing interest to the scientific community.

AIM OF REVIEW

In the review, the traditional application, botany, chemical constituents, pharmacological activities, and toxicity are comprehensively and systematically summarized.

MATERIALS AND METHODS

An extensive database retrieval was conducted to gather the specific information about AP from 1871 to 2022 using online bibliographic databases Web of Science, PubMed, SciFinder, Google Scholar, CNKI, and Baidu Scholar. The search terms comprise the keywords "Abrus precatorius", "phytochemistry", "pharmacological activity", "toxicity" and "traditional application" as a combination.

RESULTS

To date, AP is traditionally used to treat various diseases, including sore throat, cough, bronchitis, jaundice, hepatitis, abdominal pain, contraception, tumor, abortion, malaria, and so on. More than 166 chemical compounds have been identified from AP, which primarily cover flavonoids, phenolics, terpenoids, steroids, alkaloids, organic acids, esters, proteins, polysaccharides, and so on. A wide range of in vitro and in vivo pharmacological functions of AP have been reported, such as antitumor, antimicrobial, insecticidal, antiprotozoal, antiparasitic, anti-inflammatory, antioxidant, immunomodulatory, antifertility, antidiabetic, other pharmacological activities. The crushed seeds in powder or paste form were comparatively toxic to humans and animals by oral administration. Interestingly, the methanolic extracts were non-toxic to adult Wistar albino rats at various doses (200 and 400 mg/kg) daily.

CONCLUSIONS

The review focuses on the traditional application, botany, phytochemistry, pharmacological activities, and toxicity of AP, which offers a valuable context for researchers on the current research status and a reference for further research and applications of this medicinal plant.

Preliminary Investigation into the Anticonvulsant, Sedative and Muscle Relaxant Effects of the Methanolic Extract of Capparis spinosa L. Leaves in Mice

Background Capparis spinosa L is a Mediterranean plant. In Libya, the plant grows in rocky areas and at high altitudes. It is commonly used by the inhabitants of the Mediterranean region in their kitchen and treatment of many diseases.

Aim This study was undertaken to investigate the central nervous system depressant, anticonvulsant, and the muscle relaxant activities of orally administered methanolic extract from the leaves of C. spinosa L. (MECS) in mice.

Methods The oral administration of three doses of the MECS in mice (500, 1000, and 2000 mg/kg) were evaluated in the picrotoxin (PC)-induced convulsion model, ketamine-induced sleep, and rota rod test. Diazepam was used as a reference drug for comparison. Results were analyzed using SPSS program version 16. Data are presented as mean ± SEM, and compared using one-way ANOVA followed by Duncan's test. The significance level was set at p < 0.05

Results Oral administration of MECS (1000 and 2000 mg/kg) significantly prolonged the onset of seizures (p < 0.01) and produced dose-dependent protection against PC-induced seizures compared with the control group (12.5% and 50% protection, respectively). MECS significantly (p < 0.05) and dose dependently reduced ketamine sleep latency (from 3.16 ± 0.16 to a minimum of 1.5 ± 0.22 minutes) and prolonged ketamine-induced sleeping time (from 11.33 ± 1.99 to a maximum of 33.33 ± 0.95 minutes). In the accelerated rotarod test, MECS significantly (p < 0.01) decreased the riding time on the rotarod (from 128.83 ± 14.6 to a minimum of 1.83 ± 0.47 seconds) as compared with the normal saline control group.

Conclusion The results showed that the MECS possesses anticonvulsant, sedative, and muscle relaxant properties in mice.

Epilepsy research in Africa: A scoping review by the ILAE Pediatric Commission Research Advocacy Task Force

OBJECTIVE

Despite the high prevalence of epilepsy in Africa, evaluation of epilepsy research trends on the continent is lacking. Without establishing effective research, improvement in care for people with epilepsy cannot be effectively strategized or targeted.

METHODS

A scoping review of the peer-reviewed literature on epilepsy from Africa (1989-2019) was conducted. The aim was to understand from this what areas are well researched versus underresearched based on published epilepsy topics.

RESULTS

A total of 1227 publications were identified and assessed. A significant increase in publications occurred over the 30 years assessed. African author leadership was evident in most reports. Nine countries had >50 publications identified; the remaining 45 countries had <50 or no publications. Research studies were typically of lower quality (case series and observational studies). Research themes were more focused on clinical epilepsy (descriptive observational studies) and social aspects (qualitative surveys). However, there were a number of unique and strong themes, specifically for neurocysticercosis and nodding syndrome, where strong research collaborations were evident, basic science understandings were explored, and interventional models were established.

SIGNIFICANCE

Despite Africa being the continent with the most countries, it is lacking in the quantity, quality, and for some areas, relevance of research on epilepsy. Targeted approaches are needed to upskill the strength of research undertaken with more basic science, interventional, and randomized controlled studies. Themes of research need to promote those with unique African content but also to align with current international research areas that have impact on care delivery, such as epilepsy surgery and epilepsy genetics. For this to be possible, it is important to strengthen research hubs with collaborations that empower Africa to own its epilepsy research journey.

Cytotoxicity of Medicinal Plant Species Used by Traditional Healers in Treating People Suffering From HIV/AIDS in Uganda

Introduction: Many people living with HIV/AIDS (PLHIV) in Uganda widely use herbal medicines. However, their toxicity and safety have not been investigated. The use of these plants can potentially cause harmful effects to the health of patients. The purpose of this study was to determine the cytotoxicity of some commonly used medicinal plant species used by PLHIV.

Methods: The cytotoxicity of the plant extracts was determined with the AlamarBlue cell viability assay using the human glioblastoma cell line U87.CD4.CXCR4. The cells were treated with varying concentrations of extracts of Warburgia ugandensis, Erythrina abyssinica, Cryptolepis sanguinolenta, Albizia coriaria, Psorospermum febrifugium, Gymnosporia senegalensis, Zanthoxylum chalybeum, Securidaca longipendunculata, Vachellia hockii, Gardenia ternifolia, and Bridelia micrantha reconstituted with ethanol and dimethyl sulfoxide (DMSO). Using regression analysis, the half maximal cytotoxic concentration (CC₅₀) of the plant extracts were calculated from exponential curve fits, since they provided the highest coefficient of determination, R².

Results: The ethanol extracts of W. ugandensis (CC₅₀ = 7.6 μg/ml) and A. coriaria (CC₅₀ = 1.5 μg/ml) as well as the DMSO-reconstituted extracts of W. ugandensis (CC₅₀ = 6.4 μg/ml) and A. coriria (CC₅₀ = < 4 μg/ml) were highly cytotoxic. The cytotoxicity of W. ugandensis and A. coriaria compared well with the indigenous traditional knowledge of the toxic effects experienced when the plants were not used correctly. However, the cytotoxicity of most of the plant extracts (15/22) was low to moderate (CC₅₀ = 21–200 μg/ml).

Conclusion: Most of the plant species tested in this study had low to moderate cytotoxicity against U87.CD4.CXCR4 cells, except W. ugandensis and A. coriria which were highly cytotoxic.

Plant species of the genus Uvaria: ethnobotanical uses, biological activities and phytochemistry

The genus Uvaria (Annonaceae) comprises of climbing or trailing shrubs and rarely trees. Its plant species are widely distributed across tropical Africa, Asia and Australia. The genus Uvaria is known for various ethnobotanical uses including the treatment of tumours and the control of fever. Some of plant species in this genus have been studied for their ethnobotanical uses, biological activities and phytochemistry. The aim of the present study is to give a comprehensive review of plant species from the genus Uvaria in terms of their ethnobotanical uses, biological activities and phytochemistry. This review is expected to lay a foundation for further studies of this genus in terms of ethnobotanical applicability, biological activities and phytochemistry. Since many compounds currently known from the genus Uvaria have not yet been investigated for their biological activities, this review will be useful for future studies in the phytochemical investigations of lead compounds from this genus.

A Pharmacological Perspective on Plant-derived Bioactive Molecules for Epilepsy

Epilepsy is a related chronic neurological condition of a predisposition for recurrent epileptic seizures, with various manifestations and causes. Although there are antiepileptic drugs, complementary natural therapies are widely used. The purpose of this systematic review was to analyze the antiepileptic/anticonvulsant pharmacological properties of plant-food derived bioactive molecules. In this regard, a systematic review of the PubMed database was made based on the inclusion criteria. Natural compounds/herbs with scientifically proven antiepileptic properties were selected. Experimental pharmacological studies in vitro and in vivo have shown that flavonoids, alkaloids and terpenoids may have anticonvulsant mechanisms similar to the new generation antiepileptic drugs. The relationships of structure-anticonvulsant effect, pharmacological models, seizure-inducing factors and response, effective dose were also analyzed and discussed. The results of in vitro and in vivo pharmacological studies analyzed in this systematic review support the clinical importance of plant-food-derived bioactive molecules for the complementary treatment of epilepsy. Thus, are opened new perspectives to develop new natural anticonvulsant drugs.

Status analysis of herbal drug therapies in epilepsy: advancements in the use of medicinal plants with anti-inflammatory properties

BACKGROUND

Use of plants and plant products in health care has shown exponential increase in past two decades.

INTRODUCTION

In-spite of the availability of well-established pharmacotherapy for epilepsy, a large no of population still explores alternative treatments due to refractory seizures, adverse effects of drugs, chronic treatment, inaccessibility of standard therapies in rural areas and the social stigma attached to the disease. Various studies on medicinal plants showed the protective effect of herbals in animal models of epilepsy.

METHOD

In the present review, a status analysis of the traditional use of various medicinal plants in epilepsy with a special focus on plats having anti-inflammatory potential is recorded.

RESULT AND CONCLUSION

The shortcomings of research on medicinal plants which needs to be explored further in order to tackle the growing need of safer and effective drugs for epilepsy are discussed. Overall, there is a huge scope of herbal drugs in CNS disorders especially epilepsy, either as an adjunct by reducing the dose and thus side effects of standard anti-epileptic drugs or as standalone agent . Although, there is still an urgent need of well planned randomized controlled clinical trials to validate their efficacy and safety.

Herbal medicine for epilepsy seizures in Asia, Africa and Latin America: A systematic review

RELEVANCE

More than 70 million people suffer epilepsy worldwide. Low availability of anti-epileptic drugs, side-effects and drug-resistant epilepsy affect the quality of life of persons with epilepsy in countries with a poorly developed health system. Herbal medicine is frequently used for this neurological condition.

OBJECTIVES

The main objective was to provide a detailed analysis of Herbal Medicine used for neurological conditions related with epilepsy in Asia, Africa and Latin America. More broadly, this study aims to highlight species with assessed efficacy (cross-cultural use, pharmacological effects on models of epileptic seizures) and safety (toxicological data in laboratory) information, in order to point out species of interest for further studies. A critical assessment of models used in pharmacological evaluations was done.

MATERIALS AND METHODS

The systematic search for Herbal Medicine treatments for epilepsy was performed considering all the articles published until February 2017 through three scientific databases. It was made with MeSH terms and free text defining the epilepsy seizures and plant species. We included studies carried out in Asia, Africa and Latin America. All articles reporting the use of Herbal Medicine to treat epilepsy seizures and/or their pharmacological evaluation were retained for further analysis.

RESULTS

The search yielded 1886 articles, from 30 countries. Hundred and six articles published between 1982 and 2017 were included, corresponding to a total of 497 use reports for 351 plant species belonging to 106 families. Three hundred and seventy seven use reports corresponding to 264 species in ethnopharmacological surveys and 120 evaluation reports corresponding to 107 species were noted. Twenty-nine reports, for 29 species, combined both ethnopharmacological and pharmacological evaluation. Fifty eight studies originated from Africa, 35 studies from Asia and 18 from Latin America. Highest use report was noted for rhizomes of Acorus calamus L. (12 use report in 1 country) and leaves of Bacopa monnieri (L.) Wettst. (8 use report in 2 countries). Therefore these species display the highest use convergence. Regarding pharmacological evaluation most studied species were: Leonotis leonurus (L.) R.Br. (4 evaluation reports in 1 country), Uncaria rhynchophylla (Miq.) Miq. ex Havil. (3 evaluation reports in 2 countries) and Calotropis gigantea (L.) Dryand. (3 evaluation reports in 1 country). In vivo models of chronic epilepsy were more relevant than in vitro models or chemical models inducing acute seizures for pharmacological assessment.

CONCLUSION

Species with the highest use report were not those with pharmacological evaluation. It will be pertinent to assess the pharmacological effects and safety of medicinal plants used mostly by traditional healers on predictive models of seizures.

Identification of GSK-3 as a Potential Therapeutic Entry Point for Epilepsy

In view of the clinical need for new antiseizure drugs (ASDs) with novel modes of action, we used a zebrafish seizure model to screen the anticonvulsant activity of medicinal plants used by traditional healers in the Congo for the treatment of epilepsy, and identified a crude plant extract that inhibited pentylenetetrazol (PTZ)-induced seizures in zebrafish larvae. Zebrafish bioassay-guided fractionation of this anticonvulsant Fabaceae species, Indigofera arrecta, identified indirubin, a compound with known inhibitory activity of glycogen synthase kinase (GSK)-3, as the bioactive component. Indirubin, as well as the more potent and selective GSK-3 inhibitor 6-bromoindirubin-3'-oxime (BIO-acetoxime) were tested in zebrafish and rodent seizure assays. Both compounds revealed anticonvulsant activity in PTZ-treated zebrafish larvae, with electroencephalographic recordings revealing reduction of epileptiform discharges. Both indirubin and BIO-acetoxime also showed anticonvulsant activity in the pilocarpine rat model for limbic seizures and in the 6-Hz refractory seizure mouse model. Most interestingly, BIO-acetoxime also exhibited anticonvulsant actions in 6-Hz fully kindled mice. Our findings thus provide the first evidence for anticonvulsant activity of GSK-3 inhibition, thereby implicating GSK-3 as a potential therapeutic entry point for epilepsy. Our results also support the use of zebrafish bioassay-guided fractionation of antiepileptic medicinal plant extracts as an effective strategy for the discovery of new ASDs with novel mechanisms of action.

Potential of South African medicinal plants targeting the reduction of Aβ42 protein as a treatment of Alzheimer's disease

ETHNOPHARMACOLOGICAL RELEVANCE

Twenty South African medicinal plant species were selected by conducting a literature review based on the relevant information of their reported traditional medicinal uses and scientific reports against Alzheimer's disease, dementia, anxiety, mental illness, depression, acetylcholinesterase inhibition, headache, epilepsy, convulsion, hysteria, and sedative effects.

AIM OF STUDY

The goal of this study was to investigate the biological activity of the traditionally used medicinal plant extracts against Alzheimer's disease by in vitro screening of the extracts to determine their potential to decrease levels of Aβ42 protein.

MATERIAL AND METHODS

Different plant parts (leaves, stem, bark, and stalks) of twenty selected plants were collected from the Manie van der Schijff Botanical Garden, University of Pretoria. Plant parts were dried, ground and then extracted using DCM:MeOH (1:1). We measured the levels of β-amyloid precursor protein proteolytic products in HeLa cells stably transfected with APP carrying the Swedish mutation using ELISA.

RESULTS

Of 33 plant extract 10 (30.3%) were found active based on the potential to significantly reduce the production of Aβ42. Amongst them extracts of leaves of Xysmalobium undulatum (Apocynaceae), leaves of Cussonia paniculata (Araliaceae) and leaves of Schotia brachypetala (Fabaceae) potently decreased the production of Aβ42 by 77.3 ± 0.5%, 57.5 ± 1.3%, and 44.8 ± 0.1%, respectively. X. undulatum and S. brachypetala enhanced non-amyloidogenic processing of β-amyloid precursor protein, thereby decreasing Aβ42 level. We also showed that C. paniculata induced the decrease of Aβ42 level through inhibiting APP processing. In addition, we isolated two cardenolides, compound [A] and [B], from X. undulatum and found that they potently decreased the Aβ42 production.

CONCLUSION

These data suggest that the extract of X. undulatum, C. paniculata, and S. brachypetala have potential to be developed for Alzheimer's disease treatment. These active extracts and compounds are considered for further studies which examine their efficacy towards the reduction of Aβ42 through inhibiting APP process.

Clausena anisata and Dysphania ambrosioides essential oils: from ethno-medicine to modern uses as effective insecticides

Dysphania ambrosioides (L.) Mosyakin & Clemants (Amaranthaceae) and Clausena anisata (Willd.) Hook. f. ex Benth. (Rutaceae) are two aromatic species traditionally used in Cameroon to repel and kill insects. The present work was carried out to substantiate this traditional use and to evaluate the possible incorporation in commercial botanical insecticides of their essential oils (EOs). The EOs were distilled from leaves of C. anisata and aerial parts of D. ambrosioides and analyzed by gas chromatography-mass spectrometry (GC-MS). The insecticidal activity of both EOs was investigated against the filariasis vector, Culex quinquefasciatus, and the housefly, Musca domestica. As possible mode of action, the inhibition of acetylcholinesterase (AChE) by the two EOs was investigated as well. The D. ambrosioides EO was characterized by the monoterpene peroxide ascaridole (61.4%) and the aromatic p-cymene (29.0%), whereas the C. anisata EO was dominated by the phenylpropanoids (E)-anethole (64.6%) and (E)-methyl isoeugenol (16.1%). The C. anisata EO proved to be very toxic to third instar larvae of C. quinquefasciatus showing LC₅₀ of 29.3 μl/l, whereas D. ambrosioides EO was more toxic to adults of M. domestica showing a LD₅₀ of 51.7 μg/adult. The mixture of both EOs showed a significant synergistic effect against mosquito larvae with LC₅₀ estimated as 19.3 μl/l, whereas this phenomenon was not observed upon application to M. domestica adults (LD₅₀ = 75.9 μg/adult). Of the two EOs, the D. ambrosioides one provided a good inhibition of AChE (IC₅₀ = 77 μg/ml), whereas C. anisata oil was not effective. These findings provide new evidences supporting the ethno-botanical use of these two Cameroonian plants, and their possible application even in synergistic binary blends, to develop new eco-friendly, safe and effective herbal insecticides.

Trypanosoma brucei Inhibition by Essential Oils from Medicinal and Aromatic Plants Traditionally Used in Cameroon (Azadirachta indica, Aframomum melegueta, Aframomum daniellii, Clausena anisata, Dichrostachys cinerea and Echinops giganteus)

Essential oils are complex mixtures of volatile components produced by the plant secondary metabolism and consist mainly of monoterpenes and sesquiterpenes and, to a minor extent, of aromatic and aliphatic compounds. They are exploited in several fields such as perfumery, food, pharmaceutics, and cosmetics. Essential oils have long-standing uses in the treatment of infectious diseases and parasitosis in humans and animals. In this regard, their therapeutic potential against human African trypanosomiasis (HAT) has not been fully explored. In the present work, we have selected six medicinal and aromatic plants (Azadirachta indica, Aframomum melegueta, Aframomum daniellii, Clausena anisata, Dichrostachys cinerea, and Echinops giganteus) traditionally used in Cameroon to treat several disorders, including infections and parasitic diseases, and evaluated the activity of their essential oils against Trypanosma brucei TC221. Their selectivity was also determined with Balb/3T3 (mouse embryonic fibroblast cell line) cells as a reference. The results showed that the essential oils from A. indica, A. daniellii, and E. giganteus were the most active ones, with half maximal inhibitory concentration (IC₅₀) values of 15.21, 7.65, and 10.50 µg/mL, respectively. These essential oils were characterized by different chemical compounds such as sesquiterpene hydrocarbons, monoterpene hydrocarbons, and oxygenated sesquiterpenes. Some of their main components were assayed as well on T. brucei TC221, and their effects were linked to those of essential oils.

Medicinal Plants Used for Neuropsychiatric Disorders Treatment in the Hauts Bassins Region of Burkina Faso

Background: In Burkina Faso, phytotherapy is the main medical alternative used by populations to manage various diseases that affect the nervous system. The aim of the present study was to report medicinal plants with psychoactive properties used to treat neuropsychiatric disorders in the Hauts Bassins region, in the western zone of Burkina Faso. Methods: Through an ethnobotanical survey using structured questionnaire, 53 traditional healers (TH) were interviewed about neuropsychiatric disorders, medicinal plants and medical practices used to treat them. The survey was carried out over a period of three months. Results: The results report 66 plant species used to treat neuropsychiatric pathologies. Roots (36.2%) and leaves (29%) were the main plant parts used. Alone or associated, these parts were used to prepare drugs using mainly the decoction and the trituration methods. Remedies were administered via drink, fumigation and external applications. Conclusions: It appears from this study a real knowledge of neuropsychiatric disorders in the traditional medicine of Hauts Bassins area. The therapeutic remedies suggested in this work are a real interest in the fight against psychiatric and neurological diseases. In the future, identified plants could be used for searching antipsychotic or neuroprotective compounds.

Anticonvulsant activity of Dorema ammoniacum gum: evidence for the involvement of benzodiazepines and opioid receptors

This study investigated the anticonvulsant activity and possible mechanism of action of an aqueous solution of Dorema ammoniacum gum (DAG) which has been used traditionally in the treatment of convulsions. In this study, the anticonvulsant activity of DAG was examined using the pentylentetrazole (PTZ) model in mice. Thirty male albino mice were divided randomly and equally to 5 groups, and pretreated with normal saline, diazepam, or various doses of DAG (500, 700, and 1000 mg/kg, i.p.), prior to the injection of PTZ (60 mg/kg, i.p.). The latency and duration of seizures were recorded 30 min after PTZ injection. Pretreatments with naloxone and flumazenil in different groups were studied to further clarify the mechanisms of the anticonvulsant action. Phytochemical screening and thin layer chromatography (TLC) fingerprinting of ammoniacum gum was also determined. DAG showed significant anticonvulsant activity at all doses used. The gum delayed both the onset and the duration of seizures induced by PTZ. Treatment with flumazenil before DAG (700 mg/kg) inhibited the effect of gum on seizure duration and latency to some extent and administration of naloxone before DAG also significantly inhibited changes in latency and duration of seizure produced by DAG. The percentage inhibition was greater with naloxone than with flumazenil. This study showed that DAG had significant anticonvulsant activity in PTZ-induced seizures, and GABAergic and opioid systems may be involved. More studies are needed to further investigate its detailed mechanism.

Anti-inflammatory and Analgesic Effects in Rodent Models of Ethanol Extract of Clausena anisata Roots and their Chemical Constituents

The in vivo anti-inflammatory and analgesic activities of the crude ethanol extract and chemical constituents of Clausena anisata roots were investigated. The crude extract, which was devoid of any visible acute toxicity, displayed significant anti-inflammatory effect at the dose of 1000 mg/kg (p.o.) when assessed using the carrageenan-induced oedema model. In the acetic acid-induced writhing and hot plate tests, it produced a very significant ( p < 0.001), dose-dependent analgesic effect, with maximum analgesic activity of 72.1% at 1000 mg/kg (p.o.). Phytochemical analysis of the crude extract resulted in the isolation of four coumarins (anisocoumarin B, osthol, imperatorin and xanthotoxol) and a carbazole alkaloid, heptaphylline. Among the isolated compounds, osthol and anisocoumarin B produced the highest anti-inflammatory activity at 9 mg/kg (p.o.): slightly better than the positive control, indomethacin. Except for xanthotoxol, all the isolated compounds administered at 6 mg/kg (p.o.) produced significant analgesic activity and higher than diclofenac; with heptaphylline being the most potent (48.7%). The analgesic activity of anisocoumarin B (50.4%) was the highest among the isolates tested and the standard, tramadol, in the hot plate test. The nonselective opioid receptor antagonist, naloxone, abolished the analgesic effect of the crude extract and the tested isolates (anisocoumarin B and xanthotoxol) in the hot plate test suggesting an effect via the central opioidergic system. These findings provide the scientific basis for the use of C. anisata roots in traditional medicine as anti-inflammatory and analgesic agents.

Plants Producing Ribosome-Inactivating Proteins in Traditional Medicine

Ribosome-inactivating proteins (RIPs) are enzymes that deadenylate nucleic acids and are broadly distributed in the plant kingdom. Many plants that contain RIPs are listed in the pharmacopoeias of folk medicine all over the world, mostly because of their toxicity. This review analyses the position occupied in traditional medicine by plants from which RIPs have been isolated. The overview starts from the antique age of the Mediterranean area with ancient Egypt, followed by the Greek and Roman classic period. Then, the ancient oriental civilizations of China and India are evaluated. More recently, Unani medicine and European folk medicine are examined. Finally, the African and American folk medicines are taken into consideration. In conclusion, a list of RIP-expressing plants, which have been used in folk medicine, is provided with the geographical distribution and the prescriptions that are recommended by traditional healers. Some final considerations are provided on the present utilization of such herbal treatments, both in developing and developed countries, often in the absence of scientific validation. The most promising prospect for the medicinal use of RIP-expressing plants is the conjugation of purified RIPs to antibodies that recognise tumour antigens for cancer therapy.

Anticonvulsant Activity of Hydroalcoholic Extract of Citrullus colocynthis Fruit

This study investigated the anticonvulsant activity of Citrullus colocynthis fruit extract used traditionally in the treatment of convulsion. Albino mice were pretreated with extract in different doses (10, 25, 50, and 100 mg/kg), prior to injection of pentylenetetrazole. Animals received pretreatments with naloxone and flumazenil to further clarify the mechanisms of anticonvulsant action. The total flavonoid content of Citrullus colocynthis extract was also determined. Citrullus colocynthis hydroalcoholic extract with doses 25 and 50 mg/kg prolonged the onset of seizures and decreased the duration compared with control group. Pretreatment by flumazenil could inhibit the effect of Citrullus colocynthis on latency of seizure to some extent and administration of naloxone significantly inhibited changes in latency and duration of seizure produced by Citrullus colocynthis. This study showed that Citrullus colocynthis has significant anticonvulsant effect in pentylenetetrazole-induced seizures in mice, and these effects may be related to its effect on γ-aminobutyric acid-ergic and opioid systems. These results confirmed the traditional use of Citrullus colocynthis in Iranian traditional medicine.

New acyclic secondary metabolites from the biologically active fraction of Albizia lebbeck flowers

The total extract of Albizia lebbeck flowers was examined in vivo for its possible hepatoprotective activity in comparison with the standard drug silymarin at two doses. The higher dose expressed promising activity especially in reducing the levels of AST, ALT and bilirubin. Fractionation via liquid–liquid partition and reexamination of the fractions revealed that the n-butanol fraction was the best in improving liver biochemical parameters followed by the n-hexane fraction. However, serum lipid parameters were best improved with CHCl₃ fraction. The promising biological activity results initiated an intensive chromatographic purification of A. lebbeck flowers fractions. Two compounds were identified from natural source for the first time, the acyclic farnesyl sesquiterpene glycoside1-O-[6-O-α-l-arabinopyranosyl-β-d-glucopyranoside]-(2E,6E-)-farnesol (6) and the squalene derivative 2,3-dihydroxy-2,3-dihydrosqualene (9), in addition to eight compounds reported here for the first time from the genus Albizia; two benzyl glycosides, benzyl 1-O-β-d-glucopyranoside (1) and benzyl 6-O-α-l-arabinopyranosyl β-d-glucopyranoside (2); three acyclic monoterpene glycosides, linalyl β-d-glucopyranoside (3) and linalyl 6-O-α-l-arabinopyranosyl-β-d-glucopyranoside (4); (2E)-3,7-dimethylocta-2,6-dienoate-6-O-α-l arabinopyranosyl-β-d-glucopyranoside (5), two oligoglycosides, n-hexyl-α-l arabinopyranosyl-(1 → 6)-β-d-glucopyranoside (creoside) (7) and n-octyl α-l-arabinopyranosyl-(1 → 6)-β-d-glucopyranoside (rhodiooctanoside) (8); and ethyl fructofuranoside (10). The structures of the isolated compounds were elucidated based on extensive examination of their spectroscopic 1D and 2D-NMR, MS, UV, and IR data. It is worth mentioning that, some of the isolated linalol glycoside derivatives were reported as aroma precursors.

Ethnopharmacological survey of plant species used in folk medicine against central nervous system disorders in Togo

ETHNOPHARMACOLOGICAL RELEVANCE

Neurological diseases are rising all around the world. In a developing country such as Togo, although plant-based medicines are the only means, still very little is known regarding the nature and efficiency of medicinal plants used by indigenous people to manage central nervous system (CNS) disorders.

AIM OF THE STUDY

This study, an ethnobotanical survey, aimed to report plant species used in traditional medicine (TM) for the management of various CNS disorders in Togo.

MATERIALS AND METHODS

52 traditional actors (TA) including 33 traditional healers (TH) and 19 medicinal plant sellers (MPS) were interviewed, using a questionnaire mentioning informants' general data and uses of medicinal plants.

RESULTS

The present study reports 44 medicinal plant species distributed into 26 families, mentioning scientific and common local names, plant organs used, preparation method, root of administration and putative applications.

CONCLUSION

It appears that there is a real knowledge on medicinal plants used for traditional treatment of CNS disorders in Togo and that the local flora abounds of potentially neuroactive plants which could be useful for the discovery of antipsychotic or neuroprotective molecules.

Review: African medicinal plants with wound healing properties

ETHNOPHARMACOLOGICAL RELEVANCE

Wounds of various types including injuries, cuts, pressure, burns, diabetic, gastric and duodenal ulcers continue to have severe socio-economic impact on the cost of health care to patients, family and health care institutions in both developing and developed countries. However, most people in the developing countries, especially Africa, depend on herbal remedies for effective treatment of wounds. Various in vitro and in vivo parameters are used for the evaluation of the functional activity of medicinal plants by using extracts, fractions and isolated compounds. The aim of the review is to identify African medicinal plants with wound healing properties within the last two decades.

MATERIALS AND METHODS

Electronic databases such as PubMed, Scifinder(®) and Google Scholar were used to search and filter for African medicinal plants with wound healing activity. The methods employed in the evaluation of wound healing activity of these African medicinal plants comprise both in vivo and in vitro models. In vivo wound models such as excision, incision, dead space and burn wound model are commonly employed in assessing the rate of wound closure (contraction), tensile strength or breaking strength determination, antioxidant and antimicrobial activities, hydroxyproline content assay and histological investigations including epithelialisation, collagen synthesis, and granulation tissue formation. In in vitro studies, single cell systems are mostly used to study proliferation and differentiation of dermal fibroblasts and keratinocytes by monitoring typical differentiation markers like collagen and keratin.

RESULTS

In this study, 61 plants belonging to 36 families with scientifically demonstrated or reported wound healing properties were reviewed. Various plant parts including leaves, fruits, stem bark and root extracts of the plants are used in the evaluation of plants for wound healing activities.

CONCLUSION

Although, a variety of medicinal plants for wound healing can be found in literature, there is a need for the isolation and characterization of the bioactive compounds responsible for the wound healing properties. Also, cytotoxicity studies should be performed on the promising agents or bioactive fractions or extracts.

Activity of medicinal plants from Ghana against the parasitic gut protist Blastocystis

ETHNOPHARMACOLOGICAL RELEVANCE

The plants tested in this study were examples of plants historically used to treat or alleviate several types of stomach disorders manifested by e.g. stomachache, diarrhoea or dysentery. These plants have been consumed typically as a decoction, sometimes mixed with other flavourings. The aim of this study was to evaluate the anti-Blastocystis activity of 24 plant parts from 21 medicinal plants from Ghana.

MATERIALS AND METHODS

The medicinal plants were collected in the Greater Accra region of Ghana. Every plant part was tested in three different extracts; an ethanolic, a warm, and a cold water extract, at a final concentration of 1 mg/mL for the initial screening, and in a range from 0.0156 to 1mg/mL for determination of inhibitory concentrations. The obligate anaerobic parasitic gut protist Blastocystis (subtype 4) was used as a 48 h old subcultivated isolate in the final concentration of 10(6) cells/mL. Plant extracts inoculated with Blastocystis were incubated at 37 °C for 24 h and 48 h. Both MIC minimum inhibitory concentration (MIC90) assays and minimal lethal concentration (MLC) assays were performed after 24 h and 48 h. The half maximal inhibitory concentration (IC50) was derived after 24 h and 48 h. Antimicrobial activity was tested against two Gram-positive and two Gram-negative bacteria for all 24 plant parts at a final concentration of 1mg/mL.

RESULTS

Screening of the 24 different plant parts showed significant anti-Blastocystis activity of six of the ethanolic extracts: Mallotus oppositifolius, IC50, 24 h 27.8 µg/mL; Vemonia colorata, IC50, 24 h 117.9 µg/mL; Zanthoxylum zanthoxyloides, cortex IC50, 24 h 255.6 µg/mL; Clausena anisata, IC50, 24 h 314.0 µg/mL; Z. zanthoxyloides, radix IC50, 24 h 335.7 µg/mL and Eythrina senegalensis, IC50, 24 h 527.6 µg/mL. The reference anti-protozoal agent metronidazole (MTZ) had an IC50, 24 h of 7.6 µg/mL. Only C. anisata showed antimicrobial activity at a concentration of 800 µg/mL.

CONCLUSION

Six ethanolic plant extracts showed significant anti-parasitic activity against Blastocystis. M. oppositifolius showed nearly as good activity as the reference anti-protozoal drug MTZ. Historically, the active plants found in this study have been used against dysentery, diarrhoea or other stomach disorders. Nowadays they are not used specifically for dysentery, but they are being used as medicinal plants against various stomach disorders.

A pharmacological basis of herbal medicines for epilepsy

Epilepsy is the most common chronic neurological disease, affecting about 1% of the world's population during their lifetime. Most people with epilepsy can attain a seizure-free life upon treatment with antiepileptic drugs (AEDs). Unfortunately, seizures in up to 30% do not respond to treatment. It is estimated that 90% of people with epilepsy live in developing countries, and most of them receive no drug treatment for the disease. This treatment gap has motivated investigations into the effects of plants that have been used by traditional healers all over the world to treat seizures. Extracts of hundreds of plants have been shown to exhibit anticonvulsant activity in phenotypic screens performed in experimental animals. Some of those extracts appear to exhibit anticonvulsant efficacy similar to that of synthetic AEDs. Dozens of plant-derived chemical compounds have similarly been shown to act as anticonvulsants in various in vivo and in vitro assays. To a significant degree, anticonvulsant effects of plant extracts can be attributed to widely distributed flavonoids, (furano)coumarins, phenylpropanoids, and terpenoids. Flavonoids and coumarins have been shown to interact with the benzodiazepine site of the GABAA receptor and various voltage-gated ion channels, which are targets of synthetic AEDs. Modulation of the activity of ligand-gated and voltage-gated ion channels provides an explanatory basis of the anticonvulsant effects of plant secondary metabolites. Many complex extracts and single plant-derived compounds exhibit antiinflammatory, neuroprotective, and cognition-enhancing activities that may be beneficial in the treatment of epilepsy. Thus, botanicals provide a base for target-oriented antiepileptic drug discovery and development. In the future, preclinical work should focus on the characterization of the effects of plant extracts and plant-derived compounds on well-defined targets rather than on phenotypic screening using in vivo animal models of acute seizures. At the same time, available data provide ample justification for clinical studies with selected standardized botanical extracts and plant-derived compounds. This article is part of a Special Issue entitled "Botanicals for Epilepsy".

The importance of botanical treatments in traditional societies and challenges in developing countries

Epilepsy is one of the most common neurological conditions worldwide, with many affected persons found in Asia, Latin America, and sub-Saharan Africa. Relatedly, the large majority found in these regions does not receive the appropriate therapy with antiepileptic drugs (AEDs), stemming from various reasons among which are lack of access to AEDs, social stigma, and negative cultural attitudes. The presence of epilepsy resistant to the available AEDs coupled with the frequent AED side effects has further fueled the widespread and growing use of botanicals as alternative therapy in several traditional societies in these developing countries since people with epilepsy (PWE) consider them as safe and effective. There have, however, been few botanicals that have been examined for their pharmacological activities related to traditional uses, and there is hardly any conclusive evidence regarding their efficacy in humans or knowledge about the exact mechanism(s) of action. This review discusses some botanical treatments that have been used for epilepsy in developing countries and the challenges faced. This article is part of a Special Issue entitled "Botanicals for Epilepsy".

Antimicrobial Activities of a Plethora of Medicinal Plant Extracts and Hydrolates against Human Pathogens and Their Potential to Reverse Antibiotic Resistance

Microbial infections till date remain a scourge of humanity due to lack of vaccine against some infections, emergence of drug resistant phenotypes, and the resurgence of infections amongst others. Continuous quest for novel therapeutic approaches remains imperative. Here we (i) assessed the effects of extracts/hydrolates of some medicinal plants on pathogenic microorganisms and (ii) evaluated the inhibitory potential of the most active ones in combination with antibiotics. Extract E03 had the highest DZI (25 mm). Extracts E05 and E06 were active against all microorganisms tested. The MICs and MBCs of the methanol extracts ranged from 16.667 × 10³  μg/mL to 2 μg/mL and hydrolates from 0.028 to 333333 ppm. Extract E30 had the highest activity especially against S. saprophyticus (MIC of 6 ppm) and E. coli (MIC of 17 ppm). Combination with conventional antibiotics was shown to overcome resistance especially with E30. Analyses of the extracts revealed the presence of alkaloids, flavonoids, triterpenes, steroids, phenols, and saponins. These results justify the use of these plants in traditional medicine and the practice of supplementing decoctions/concoctions with conventional antibiotics. Nauclea pobeguinii (E30), the most active and synergistic of all these extracts, and some hydrolates with antimicrobial activity need further exploration for the development of novel antimicrobials.

Warburgia: a comprehensive review of the botany, traditional uses and phytochemistry

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Warburgia (Canellaceae) is represented by several medicinal trees found exclusively on the African continent. Traditionally, extracts and products produced from Warburgia species are regarded as important natural African antibiotics and have been used extensively as part of traditional healing practices for the treatment of fungal, bacterial and protozoal infections in both humans and animals. We here aim to collate and review the fragmented information on the ethnobotany, phytochemistry and biological activities of ethnomedicinally important Warburgia species and present recommendations for future research.

MATERIALS AND METHODS

Peer-reviewed articles using "Warburgia" as search term ("all fields") were retrieved from Scopus, ScienceDirect, SciFinder and Google Scholar with no specific time frame set for the search. In addition, various books were consulted that contained botanical and ethnopharmacological information.

RESULTS

The ethnopharmacology, phytochemistry and biological activity of Warburgia are reviewed. Most of the biological activities are attributed to the drimane sesquiterpenoids, including polygodial, warburganal, muzigadial, mukaadial and ugandensial, flavonoids and miscellaneous compounds present in the various species. In addition to anti-infective properties, Warburgia extracts are also used to treat a wide range of ailments, including stomach aches, fever and headaches, which may also be a manifestation of infections. The need to record anecdotal evidence is emphasised and conservation efforts are highlighted to contribute to the protection and preservation of one of Africa's most coveted botanical resources.

Zebrafish bioassay-guided microfractionation identifies anticonvulsant steroid glycosides from the Philippine medicinal plant Solanum torvum

Medicinal plants used for the treatment of epilepsy are potentially a valuable source of novel antiepileptic small molecules. To identify anticonvulsant secondary metabolites, we performed an in vivo, zebrafish-based screen of medicinal plants used in Southeast Asia for the treatment of seizures. Solanum torvum Sw. (Solanaceae) was identified as having significant anticonvulsant activity in zebrafish larvae with seizures induced by the GABAA antagonist pentylenetetrazol (PTZ). This finding correlates well with the ethnomedical use of this plant in the Philippines, where a water decoction of S. torvum leaves is used to treat epileptic seizures. HPLC microfractionation of the bioactive crude extract, in combination with the in vivo zebrafish seizure assay, enabled the rapid localization of several bioactive compounds that were partially identified online by UHPLC-TOF-MS as steroid glycosides. Targeted isolation of the active constituents from the methanolic extract enabled the complete de novo structure identification of the six main bioactive compounds that were also present in the traditional preparation. To partially mimic the in vivo metabolism of these triterpene glycosides, their common aglycone was generated by acid hydrolysis. The isolated molecules exhibited significant anticonvulsant activity in zebrafish seizure assays. These results underscore the potential of zebrafish bioassay-guided microfractionation to rapidly identify novel bioactive small molecules of natural origin.

Anticonvulsant effect of ferula assa-foetida oleo gum resin on chemical and amygdala-kindled rats

Background:

In Iranian traditional medicine, Ferula assa-foetida oleo gum resin (asafoetida) have been used as anti-convulsant agents.

Aims:

This study was designed to evaluate the anti-convulsant effect of asafoetida on chemical and amygdala -kindled rats.

Materials and Methods:

In chemical model, rats received orally asafoetida at dose of 50 and 100 mg/kg 90 minutes prior to Pentylenetetrazol injection in dose of 35 mg/kg intraperitoneally (i.p.) and control group received normal saline. Convulsive behavior was recorded for 30 minutes. For amygdala kindle model, bipolar stimulating and monopolar recording electrodes were implanted stereotaxically. After kindling, the effect of asafoetida (50 and 100mg/kg) on after discharge duration, duration of stage 5 seizure and latency to the onset of bilateral forelimb clonuses was measured.

Results:

Pretreatment animals with asafoetida significantly reduced the mean seizure stage during the 20 kindling injection of Pentylenetetrazol. Seizure parameters in amigdala kindle model improved in treatment animals at both dose 50 and 100 mg/kg. The number of stimulations in stage 3, 4, and 5 in asafoetida-treated rats at both doses significantly increased.

Conclusions:

These results showed that asafoetida could prevent seizure in both chemical and electrical kindling model and this effect may partially be related to the terpenoids compounds.

Efficacy of Iranian traditional medicine in the treatment of epilepsy

Epilepsy is a brain disorder which affects about 50 million people worldwide. Ineffectiveness of the drugs in some cases and the serious side effects and chronic toxicity of the antiepileptic drugs lead to use of herbal medicine as a form of complementary and alternative medicine. In this review modern evidences for the efficacy of antiepileptic medicinal plants in Traditional Iranian Medicine (TIM) will be discussed. For this purpose electronic databases including PubMed, Scopus, Sciencedirect, and Google Scholar were searched for each of the antiepileptic plants during 1970-February 2013.Anticonvulsant effect of some of the medicinal plants mentioned in TIM like Anacyclus pyrethrum, Pimpinella anisum, Nigella sativa, and Ferula gummosa was studied with different models of seizure. Also for some of these plants like Nigella sativa or Piper longum the active constituent responsible for antiepileptic effect was isolated and studied. For some of the herbal medicine used in TIM such as Pistacia lentiscus gum (Mastaki), Bryonia alba (Fashra), Ferula persica (Sakbinaj), Ecballium elaterium (Ghesa-al Hemar), and Alpinia officinarum (Kholanjan) there is no or not enough studies to confirm their effectiveness in epilepsy. It is suggested that an evaluation of the effects of these plants on different epileptic models should be performed.

Chemical constituents from stem bark and roots of Clausena anisata

Phytochemical investigations on the stem bark and roots of the tropical shrub Clausena anisata led to the isolation and characterization three carbazole alkaloids: girinimbine, murrayamine-A and ekeberginine; two peptide derivatives: aurantiamide acetate and N-benzoyl-l-phenylalaninyl-N-benzoyl-l-phenylalaninate; and a mixture of two phytosterols: sitosterol and stigmasterol. The structures of these compounds were established by nuclear magnetic resonance (¹H-NMR, ¹³C-NMR, COSY, HSQC, HMQC, HMBC and NOESY) spectroscopy and electrospray ionization mass spectrometry (MS).

Antiplasmodial Activity of the Ethnobotanical Plant Cassia fistula

In our ongoing investigation of new compounds with activity against malaria parasites, we tested the in vitro antiplasmodial activity of fractions and purified compounds from Cassia fistula L., a plant traditionally used by native populations of Tanzania, Zimbabwe, Mozambique and Brazil to treat malaria or symptoms associated with this disease. Crude extracts from leaves, bark and fruits were tested for their antiplasmodial activity against the chloroquine-sensitive strain of Plasmodium falciparum(D10), where leaf extracts showed the highest activity. The chloroform extract of the leaves was further bioassay-guided fractionated using a combination of centrifugal partition chromatography and flash column chromatography. Three main antiplasmodial principles, phytol (1) (IC50 18.9 ± 0.60 μM), lutein (2) (IC50 12.5 ± 0.35 μM), and di-lineolylgalactopyranosyl-glycerol (DLGG) (IC50 5.8 ± 0.27 μM) (3), were isolated and identified using spectroscopic methods. When the three active principles were tested for their cytotoxicity using a Chinese Hamster Ovarian (CHO) cell line, compound 3 showed very weak toxicity (IC50 75.9 ± 0.28 μM), while the other two compounds were nontoxic, even at the highest concentration tested. The study provides evidence to support the use of Cassia fistula as an antimalarial remedy and describes the antiplasmodial constituents from the leaves.

Role of saponins for the anticonvulsant effect of adventitious roots of Ficus religiosa

CONTEXT

The adventitious roots of Ficus religiosa L. (Moraceae) have been extensively used in traditional medicine for treatment of several disorders, including epilepsy.

OBJECTIVE

To investigate the possible anticonvulsant effect of the adventitious roots of Ficus religiosa, and to find the biologically active fraction, to substantiate its traditional use in epilepsy.

METHODS

The hydroethanolic extract of adventitious roots (5, 10, and 20 mg/kg; i.p.) of Ficus religiosa and its different fractions (hexane, chloroform, ethyl acetate, butanol, aqueous, saponins-rich, and saponins-lacking) at a dose equivalent to 20 mg/kg of the extract were administered 30 min prior to the induction of maximal electroshock (MES) and pentylenetetrazol (PTZ) convulsions. Duration of tonic hind-limb extension (THLE) and latency to clonic convulsions were noted in MES and PTZ tests, respectively. Neurotoxicity was assessed using rotarod test.

RESULTS

Treatment with the root extract (5, 10, and 20 mg/kg; i.p.), butanolic (6 mg/kg; i.p.) and saponins-rich fractions (3.4 mg/kg; i.p.) significantly (p < 0.05) decreased the duration of THLE in MES test, as compared to control. The same treatment also significantly (p < 0.05) increased the latency to PTZ-induced clonic convulsions in comparison to control. The other fractions were found to be ineffective. The root extract and its active fractions at their effective doses showed no neurotoxic effects.

CONCLUSION

The present study concluded that the hydroethanolic extract of adventitious roots of Ficus religiosa has anticonvulsant activity. Retention of anticonvulsant effect in the saponins-rich fraction-treated animals indicated the role of saponins for the activity.

Ethnodiagnostic skills of the digo community for malaria: a lead to traditional bioprospecting

Malaria is a major public health problem that is presently complicated by the development of resistance by Plasmodium falciparum to the mainstay drugs. Thus, new drugs with unique structures and mechanism of action are required to treat drug-resistant strains of malaria. Historically, compounds containing a novel structure from natural origin represent a major source for the discovery and development of new drugs for several diseases. This paper presents ethnophytotherapeutic remedies, ethnodiagnostic skills, and related traditional knowledge utilized by the Digo community of the Kenyan Coast to diagnose malaria as a lead to traditional bioprospecting. The current study was carried out in three Digo villages of Diani sub-location between May 2009 and December 2009. Data was collected using semi-structured interviews, and open and close-ended questionnaires. A total of 60 respondents (34 men and 26 women) provided the targeted information. The results show that the indigenous knowledge of Digo community on malaria encompasses not only the symptoms of malaria but also the factors that are responsible for causing malaria, attributes favoring the breeding of mosquitoes and practices employed to guard against mosquito bites or to protect households against malaria. This knowledge is closely in harmony with scientific approaches to the treatment and control of the disease. The Digo community uses 60 medicinal plants distributed in 52 genera and 27 families to treat malaria. The most frequently mentioned symptoms were fever, joint pains, and vomiting while the most frequently mentioned practices employed to guard against mosquito bites and/or to protect households against malaria was burning of herbal plants such as Ocimum suave and ingestion of herbal decoctions and concoctions. The Digo community has abundant ethnodiagnostic skills for malaria which forms the basis of their traditional bioprospecting techniques.

Anticonvulsant activity of aqueous root extract of Ficus religiosa

ETHNOPHARMACOLOGICAL RELEVANCE

Ficus religiosa Linn is frequently used for the treatment of nervous disorders among Pawara tribe of the Satpuda range, India.

AIM OF THE STUDY

This study aimed to investigate the anticonvulsant activity of the aqueous aerial root extract of Ficus religiosa in chemoconvulsant-induced seizures in mice.

MATERIALS AND METHODS

The anticonvulsant activity of the extract (25, 50 and 100 mg/kg, p.o.) was investigated in strychnine-, pentylenetetrazole-, picrotoxin- and isoniazid-induced seizures in mice. Rat ileum and fundus strip preparations were used to study the effect of the extract on acetylcholine (Ach)- and serotonin (5-HT)-induced contractions, respectively.

RESULTS

The extract showed no toxicity and protected the animals in the strychnine and pentylenetetrazole tests in a dose-dependent manner. Its effect in the picrotoxin and isoniazid tests, however, was less potent. The extract also exhibited dose-dependent potentiation of Ach in rat ileum but failed to potentiate the effect of 5-HT in rat fundus strip preparation.

CONCLUSIONS

The results suggest that an orally administered aqueous root extract of Ficus religiosa has dose-dependent and potent anticonvulsant activities against strychnine- and pentylenetetrazole-induced seizures. The observed activities may be ascribed to the appreciable content of zinc and magnesium in the extract.

Evaluation of the anti-inflammatory properties of Dodonaea polyandra, a Kaanju traditional medicine

ETHNOPHARMACOLOGICAL RELEVANCE

Extracts of the medicinal plant species Dodonaea polyandra were investigated as part of a collegial research partnership between Northern Kaanju traditional owners represented by Chuulangun Aboriginal Corporation (centred on the Wenlock and Pascoe Rivers, Cape York Peninsula, Queensland, Australia) and university-based researchers. D. polyandra, known as "Uncha" in Kaanju language, is used in Northern Kaanju Traditional Medicine for relief from pain associated with toothache and related ailments. The species has a restricted distribution in Cape York Peninsula and there has been no previous Western scientific investigation of its pharmacology or chemistry.

AIM OF THE STUDY

The current study investigates the anti-inflammatory effects of several extracts from D. polyandra.

MATERIALS AND METHODS

Phytochemical screening was conducted using TLC. Anti-inflammatory effects of leaf extracts were determined using an acute mouse ear oedema model induced by croton oil and 12-o-tetradecanoylphorbol-13-acetate (TPA) chemical irritants.

RESULTS

Flavonoid and terpenoid secondary compounds were detected in leaf extracts of D. polyandra. Non-polar hexane and methylene chloride/methanol extracts showed potent inhibition of inflammation in TPA-induced mouse ear oedema by 72.12 and 79.81%, respectively, after 24 h at 0.4 mg/ear.

CONCLUSION

In a mouse model of acute inflammation, this study revealed that leaf extracts of D. polyandra possess significant anti-inflammatory potential. These results contribute to a Western scientific understanding of the ethnopharmacological use of the plant in Northern Kaanju Medicine for reducing tooth-related pain.

Traditional antimalarial phytotherapy remedies used by the South Coast community, Kenya

AIM OF THE STUDY

This study was conducted to document herbal medicines used in the treatment of malaria as well as the existing knowledge, attitudes and practices related to malaria recognition, control and treatment in South Coast, Kenya.

METHODS

Data was collected using semistructured questionnaires and interviews. A focused group discussion held with the community members, one in each of the study villages supplemented the interview and questionnaire survey.

RESULTS

The respondents were found to have a good understanding of malaria and could distinguish it from other fever types. They were also aware that malaria was spread by mosquitoes. Malaria prevalence was high, and affected individuals an average of four times a year. Community members avoided mosquito bites by using mosquito nets, clearing bushes around their homesteads and burning plant parts to generate smoke. They prevented and treated malaria by taking decoctions or concoctions of traditional herbal remedies. Forty plant species in thirty-five genera distributed in twenty-four families were used as antimalarials in the study area. Five plant species, namely; Heeria insignis Del. (Anacardiaceae), Rottboelia exaltata L.F (Gramineae), Pentanisia ouranogyne S. Moore (Rubiaceae), Agathisanthenum globosum (A. Rich) Hiern (Rubiaceae), and Grewia trichocarpa Hochst ex A. Rich (Tiliaceae) are documented for the first time in South Coast, Kenya, for the treatment of malaria.

CONCLUSIONS

The plants documented in the current study are a potential source for new bioactive compounds of therapeutic value in malaria treatment. The results provide data for further pharmacological and toxicological studies and development of commercial antimalarial phytotherapy products.

Antimicrobial and antimalarial activity of Cussonia species (Araliaceae)

ETHNOPHARMACOLOGICAL RELEVANCE

Cussonia species are used in African traditional medicine mainly against pain, inflammation, gastro-intestinal problems, malaria and sexually transmitted diseases.

AIM OF THE STUDY

To summarise ethnomedicinal uses of Cussonia and to find scientific evidence in support of selected main uses.

MATERIALS AND METHODS

Using the minimum inhibitory concentration (MIC) method, leaves of 13 Cussonia species, Schefflera umbellifera and Seemannaralia gerrardii were tested against pathogens associated with diarrhoea (Enterococcus faecalis and Escherichia coli), sexually transmitted infections (Neisseria gonorrhoeae and Trichomonas vaginalis) and general infectious diseases (Staphylococcus aureus and Pseudomonas aeruginosa). Antimalarial sensitivity was studied using Plasmodium falciparum and the [(3)H]-hypoxanthine incorporation assay. Cytotoxic effects on a T-cell leukaemia (Jurkat) cell line were determined using the tetrazolium-based cellular toxicity assay.

RESULTS

Methanolic extracts were active against Pseudomonas aeruginosa (MIC of 1.0-1.5 mg/mL), Trichomonas vaginalis (MIC of 0.8-1.3 mg/mL) and Staphylococcus aureus (Cussonia arborea, 1.8 mg/mL). All samples were active against Neisseria gonorrhoeae (MIC of 0.02-0.7 mg/mL). The methanol extract of Cussonia arborea was the most active against Plasmodium falciparum (13.68 microg/mL) and showed anticancer properties (5.60 microg/mL).

CONCLUSIONS

The traditional use of Cussonia species to treat sexually transmitted diseases and Plasmodium infections appears to have a scientific basis.

Natural Products in Epilepsy-the Present Situation and Perspectives for the Future

More efficacious and better tolerated treatments for epilepsy are clearly needed. Complementary and alternative medicine (CAM) has a long history of use in certain parts of the world and has gained increasing interest over the last decades in Western countries. In countries with a Western-based type of medical system, people with epilepsy (PWE) take natural products or engage in other forms of CAM mainly to enhance general health, but also to prevent seizures or to alleviate symptoms of comorbidities or side effects of antiepileptic medications. In other countries, well developed medical systems, such as traditional Chinese Medicine and Ayurveda, are often the basis for treating PWE. Based on anecdotal reports of efficacy in PWE, natural products from these and other traditions are increasingly being studied in animal models of epilepsy, and candidates for further clinical development have been identified. It is likely, therefore, that natural products will be further evaluated for safety, tolerability and efficacy in PWE with drug-resistant seizures.

Tamarindus indica L. (Fabaceae): patterns of use in traditional African medicine

To increase the understanding of the ethnopharmacology of a single species, elaboration of dispersed primary data is required. Tamarindus indica L. (Fabaceae), or tamarind, is a common tree, especially in West Africa, with a good potential to contribute to affordable local health care based on traditional medicine (TM). For this single species review, more than 60 references with detailed information on the ethnopharmacology of Tamarindus indica in the African context were selected. It showed that most prominently, the fruits are used as laxative or febrifuge throughout the Sahel and Soudan ecological zones. Tamarind bark and leaves are often involved in the treatment of wounds, especially in central West Africa. While the bark is used to treat diarrhoea in West Africa, the leaves are used for this purpose in East Africa. Our findings suggest a difference in the way tamarind is used between East and West Africa and we assess the similarities of its uses within those regions. This review demonstrates the capability of literature research to reveal knowledge by mining and compiling information from the growing body of primary ethnopharmacologic data, much of which is published in this journal. By creating a specific profile of tamarind in the context of traditional medicine throughout Africa, the authors contribute to the collection of current ethnobotanic species accounts on Tamarindus indica that tend to be qualitative and more general.

A community survey of knowledge, perceptions, and practice with respect to epilepsy among traditional healers in the Batibo Health District, Cameroon

OBJECTIVE

The purpose of this study was to gain an understanding of the approach of traditional healers to epilepsy care, in order to develop a community-based epilepsy care program in Batibo Health District.

METHODS

With an 18-item questionnaire, interviews were carried out with 102 traditional healers randomly selected from two associations of traditional healers in the Batibo Health District.

RESULTS

Most traditional healers had heard about epilepsy (98.0%), knew someone with epilepsy (97.8%), or had witnessed a seizure (92.2%). About 40% would object to their children associating with people with epilepsy (PWE), 46.1% would object to their children marrying PWE, and 51% linked the disease to insanity. Though 61.8% of the traditional healers could not offer any treatment for epilepsy, most of them thought it was treatable (74.5%) and would readily refer a patient to the hospital (95.1%). The independent predictors of attitudes were: middle age (30-49 years), P=0.00003; female gender, P=0.007; correct knowledge of the cause(s) of epilepsy, P=0.001; and the misconceptions that epilepsy is contagious and that epilepsy is a form of insanity, P=0.003 and 0.019, respectively.

CONCLUSION

Traditional healers constituted the focus group studied so far in Cameroon that is most familiar with epilepsy. Although they still have some negative practices, the attitudes of traditional healers toward PWE in Batibo Health District are satisfactory, compared with those of the general public and students in the same community. These findings provide evidence for the first time in Cameroon suggesting that collaboration between the modern and traditional health systems with the view of bridging the epilepsy treatment gap is possible. There is a need to train traditional healers in epilepsy care in our context.