A Systematic Review of In Vitro Activity of Medicinal Plants from Sub-Saharan Africa against Campylobacter spp.

Introduction. Campylobacter spp. are zoonotic bacteria that cause gastroenteritis in humans and may cause extraintestinal infections such as Guillain-Barré syndrome, reactive arthritis, and bacteremia. Resistance to antibiotics is an increasing concern in the Sub-Saharan Africa; thus, search for alternatives such as plant-based active ingredients is important in order to develop new drugs. Objectives. To present a systematic review of in vitro and in vivo studies of the antibacterial activity of medicinal plants from Sub-Saharan Africa against Campylobacter spp. Methodology. Studies published until March 2020 on medicinal plants used against Campylobacter spp. from each country of Sub-Saharan Africa were searched on PubMed, Science Direct, AJOL, and Google Scholar. Articles were selected based on the existence of information regarding in vitro and in vivo activity of medicinal plants against Campylobacter spp. Results. A total of 47 medicinal plants belonging to 28 families were studied for in vitro activity against Campylobacter spp. No plant was studied in vivo. Plants from Fabaceae family were the most commonly studied. The plants with the strongest antimicrobial activities were Cryptolepis sanguinolenta and Terminalia macroptera. The root extracts from these plants were effective, and both had a minimal inhibitory concentration (MIC) of 25 μg/ml. Seven pure compounds were isolated and analyzed for activity against Campylobacter spp. The compound cryptolepine from C. sanguinolenta was the most effective with MIC values ranging between 6.25 and 25 μg/ml. Conclusion. Several native plants from the Sub-Saharan Africa region were studied for in vitro activity against Campylobacter spp. Some plants seemed very effective against the bacteria. Chemical compounds from three plants have been isolated and analyzed, but further studies are needed in order to produce new and effective drugs.

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Schistosoma mansoni eggs induce Wnt/β-catenin signaling and activate the protooncogene c-Jun in human and hamster colon

Scientific Reports ◽

10.1038/s41598-020-79450-4 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Jakob Weglage ◽

Friederike Wolters ◽

Laura Hehr ◽

Jakob Lichtenberger ◽

Celina Wulz ◽

...

Keyword(s):

Signaling Pathways ◽

Colorectal Carcinogenesis ◽

Sub Saharan Africa ◽

Interleukin 4 ◽

Health Burden ◽

Sub Saharan ◽

Considerable Morbidity ◽

First Time

AbstractSchistosomiasis (bilharzia) is a neglected tropical disease caused by parasitic flatworms of the genus Schistosoma, with considerable morbidity in parts of the Middle East, South America, Southeast Asia, in sub-Saharan Africa, and particularly also in Europe. The WHO describes an increasing global health burden with more than 290 million people threatened by the disease and a potential to spread into regions with temperate climates like Corsica, France. The aim of our study was to investigate the influence of S. mansoni infection on colorectal carcinogenic signaling pathways in vivo and in vitro. S. mansoni infection, soluble egg antigens (SEA) and the Interleukin-4-inducing principle from S. mansoni eggs induce Wnt/β-catenin signaling and the protooncogene c-Jun as well as downstream factor Cyclin D1 and markers for DNA-damage, such as Parp1 and γH2a.x in enterocytes. The presence of these characteristic hallmarks of colorectal carcinogenesis was confirmed in colon biopsies from S. mansoni-infected patients demonstrating the clinical relevance of our findings. For the first time it was shown that S. mansoni SEA may be involved in the induction of colorectal carcinoma-associated signaling pathways.

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Medicinal Plants with Anti-Trichomonas vaginalis Activity in Iran: A Systematic Review

Iranian Journal of Parasitology ◽

10.18502/ijpa.v14i1.712 ◽

2019 ◽

Cited By ~ 2

Author(s):

Hajar ZIAEI HEZARJARIBI ◽

Najmeh NADEALI ◽

Mahdi FAKHAR ◽

Masoud SOOSARAEI

Keyword(s):

Systematic Review ◽

Medicinal Plants ◽

Trichomonas Vaginalis ◽

Scientific Information ◽

Medicinal Herbs ◽

In Vivo Studies ◽

Eligibility Criteria ◽

Sexually Transmitted

Background: Trichomoniasis, due to Trichomonas vaginalis, is one of the most common sexually transmitted parasitic diseases in the world such as Iran. This systematic review aimed to explore the studies evaluating the medicinal herbs with anti- T. vaginalis activity which used in Iran. Methods: Articles published in 4 Persian and 4 English databases were obtained between 2000 and 2015 including Google Scholar, PubMed, Science Direct, Scopus, Magiran, Barakatkns (formerly IranMedex), Elm net, and SID (Scientific Information Database). Studies out of Iran, studies on animal models and articles on other parasite species than T. vaginalis were excluded from this review. Results: Twenty-one articles including in vitro experiments, met our eligibility criteria. Thoroughly, 26 types of plants were examined against T. vaginalis. Medicinal herbs such as Artemisia, Zataria multiflora, and Lavandula angustifolia are remarkably effective on T. vaginalis. As such, use of other parts of these plants in different concentrations and timelines is recommended for future in vivo studies. Conclusion: The present systematic review provides comprehensive and useful information about Iranian medicinal plants with anti-T. vaginalis activity, which would be examined in the future experimental and clinical trials and herbal combination therapy.

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In vitro and In vivo Antimicrobial Activities of Medicinal Plants against Crown Gall in Grapevine

Korean Journal of Horticultural Science&Technology ◽

10.12972/kjhst.20160055 ◽

2016 ◽

Vol 34 (4) ◽

Keyword(s):

Medicinal Plants ◽

Crown Gall ◽

Antimicrobial Activities

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Physiological Differences in Cryptococcus neoformans Strains In Vitro versus In Vivo and Their Effects on Antifungal Susceptibility

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02108-16 ◽

2016 ◽

Vol 61 (3) ◽

Cited By ~ 13

Author(s):

Nina T. Grossman ◽

Arturo Casadevall

Keyword(s):

Cryptococcus Neoformans ◽

Cryptococcal Meningitis ◽

Antifungal Susceptibility ◽

Sub Saharan Africa ◽

Content Type ◽

Laboratory Conditions ◽

Physiological Differences ◽

Sub Saharan

ABSTRACT Cryptococcus neoformans is an environmentally ubiquitous fungal pathogen that primarily causes disease in people with compromised immune systems, particularly those with advanced AIDS. There are estimated to be almost 1 million cases per year of cryptococcal meningitis in patients infected with human immunodeficiency virus, leading to over 600,000 annual deaths, with a particular burden in sub-Saharan Africa. Amphotericin B (AMB) and fluconazole (FLC) are key components of cryptococcal meningitis treatment: AMB is used for induction, and FLC is for consolidation, maintenance and, for occasional individuals, prophylaxis. However, the results of standard antifungal susceptibility testing (AFST) for AMB and FLC do not correlate well with therapeutic outcomes and, consequently, no clinical breakpoints have been established. While a number of explanations for this absence of correlation have been proffered, one potential reason that has not been adequately explored is the possibility that the physiological differences between the in vivo infection environment and the in vitro AFST environment lead to disparate drug susceptibilities. These susceptibility-influencing factors include melanization, which does not occur during AFST, the size of the polysaccharide capsule, which is larger in infecting cells than in those grown under normal laboratory conditions, and the presence of large polyploid “titan cells,” which rarely occur under laboratory conditions. Understanding whether and how C. neoformans differentially expresses mechanisms of resistance to AMB and FLC in the AFST environment compared to the in vivo environment could enhance our ability to interpret AFST results and possibly lead to the development of more applicable testing methods.

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Antiplasmodial, antimalarial activities and toxicity of African medicinal plants: a systematic review of literature

Malaria Journal ◽

10.1186/s12936-021-03866-0 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Elahe Tajbakhsh ◽

Tebit Emmanuel Kwenti ◽

Parya Kheyri ◽

Saeed Nezaratizade ◽

David S. Lindsay ◽

...

Keyword(s):

Systematic Review ◽

Medicinal Plants ◽

Plant Species ◽

Azadirachta Indica ◽

Antiplasmodial Activity ◽

Research Articles ◽

Moderate Activity ◽

Maytenus Senegalensis

Abstract Background Malaria still constitutes a major public health menace, especially in tropical and subtropical countries. Close to half a million people mainly children in Africa, die every year from the disease. With the rising resistance to frontline drugs (artemisinin-based combinations), there is a need to accelerate the discovery and development of newer anti-malarial drugs. A systematic review was conducted to identify the African medicinal plants with significant antiplasmodial and/or anti-malarial activity, toxicity, as wells as assessing the variation in their activity between study designs (in vitro and in vivo). Methods Key health-related databases including Google Scholar, PubMed, PubMed Central, and Science Direct were searched for relevant literature on the antiplasmodial and anti-malarial activities of African medicinal plants. Results In total, 200 research articles were identified, a majority of which were studies conducted in Nigeria. The selected research articles constituted 722 independent experiments evaluating 502 plant species. Of the 722 studies, 81.9%, 12.4%, and 5.5% were in vitro, in vivo, and combined in vitro and in vivo, respectively. The most frequently investigated plant species were Azadirachta indica, Zanthoxylum chalybeum, Picrilima nitida, and Nauclea latifolia meanwhile Fabaceae, Euphorbiaceae, Annonaceae, Rubiaceae, Rutaceae, Meliaceae, and Lamiaceae were the most frequently investigated plant families. Overall, 248 (34.3%), 241 (33.4%), and 233 (32.3%) of the studies reported very good, good, and moderate activity, respectively. Alchornea cordifolia, Flueggea virosa, Cryptolepis sanguinolenta, Zanthoxylum chalybeum, and Maytenus senegalensis gave consistently very good activity across the different studies. In all, only 31 (4.3%) of studies involved pure compounds and these had significantly (p = 0.044) higher antiplasmodial activity relative to crude extracts. Out of the 198 plant species tested for toxicity, 52 (26.3%) demonstrated some degree of toxicity, with toxicity most frequently reported with Azadirachta indica and Vernonia amygdalina. These species were equally the most frequently inactive plants reported. The leaves were the most frequently reported toxic part of plants used. Furthermore, toxicity was observed to decrease with increasing antiplasmodial activity. Conclusions Although there are many indigenous plants with considerable antiplasmodial and anti-malarial activity, the progress in the development of new anti-malarial drugs from African medicinal plants is still slothful, with only one clinical trial with Cochlospermum planchonii (Bixaceae) conducted to date. There is, therefore, the need to scale up anti-malarial drug discovery in the African region.

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Solution structure, glycan specificity and of phenol oxidase inhibitory activity of Anopheles C-type lectins CTL4 and CTLMA2

Scientific Reports ◽

10.1038/s41598-019-51353-z ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Ritika Bishnoi ◽

Gregory L. Sousa ◽

Alicia Contet ◽

Christopher J. Day ◽

Chun-Feng David Hou ◽

...

Keyword(s):

Malaria Vector ◽

Solution Structure ◽

Biochemical Characterization ◽

Phenol Oxidase ◽

Sub Saharan Africa ◽

Scattering Data ◽

Molecular Features ◽

Sub Saharan

Abstract Malaria, the world’s most devastating parasitic disease, is transmitted between humans by mosquitoes of the Anopheles genus. An. gambiae is the principal malaria vector in Sub-Saharan Africa. The C-type lectins CTL4 and CTLMA2 cooperatively influence Plasmodium infection in the malaria vector Anopheles. Here we report the purification and biochemical characterization of CTL4 and CTLMA2 from An. gambiae and An. albimanus. CTL4 and CTLMA2 are known to form a disulfide-bridged heterodimer via an N-terminal tri-cysteine CXCXC motif. We demonstrate in vitro that CTL4 and CTLMA2 intermolecular disulfide formation is promiscuous within this motif. Furthermore, CTL4 and CTLMA2 form higher oligomeric states at physiological pH. Both lectins bind specific sugars, including glycosaminoglycan motifs with β1-3/β1-4 linkages between glucose, galactose and their respective hexosamines. Small-angle x-ray scattering data supports a compact heterodimer between the CTL domains. Recombinant CTL4/CTLMA2 is found to function in vivo, reversing the enhancement of phenol oxidase activity in dsCTL4-treated mosquitoes. We propose these molecular features underline a common function for CTL4/CTLMA2 in mosquitoes, with species and strain-specific variation in degrees of activity in response to Plasmodium infection.

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In Vitro, Ex Vivo, and In Vivo Activities of Diamidines against Trypanosoma congolense and Trypanosoma vivax

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02356-16 ◽

2017 ◽

Vol 61 (5) ◽

Cited By ~ 6

Author(s):

Kirsten Gillingwater ◽

Christina Kunz ◽

Christiane Braghiroli ◽

David W. Boykin ◽

Richard R. Tidwell ◽

...

Keyword(s):

Ex Vivo ◽

Trypanosoma Congolense ◽

Tsetse Fly ◽

Sub Saharan Africa ◽

Content Type ◽

Lead Compounds ◽

Single Bolus Dose ◽

Sub Saharan

ABSTRACT African animal trypanosomosis (AAT) is caused by the tsetse fly-transmitted protozoans Trypanosoma congolense and T. vivax and leads to huge agricultural losses throughout sub-Saharan Africa. Three drugs are available to treat nagana in cattle (diminazene diaceturate, homidium chloride, and isometamidium chloride). With increasing reports of drug-resistant populations, new molecules should be investigated as potential candidates to combat nagana. Dicationic compounds have been demonstrated to have excellent efficacy against different kinetoplastid parasites. This study therefore evaluated the activities of 37 diamidines, using in vitro and ex vivo drug sensitivity assays. The 50% inhibitory concentrations obtained ranged from 0.007 to 0.562 μg/ml for T. congolense and from 0.019 to 0.607 μg/ml for T. vivax. On the basis of these promising results, 33 of these diamidines were further examined using in vivo mouse models of infection. Minimal curative doses of 1.25 mg/kg of body weight for both T. congolense- and T. vivax-infected mice were seen when the diamidines were administered intraperitoneally (i.p.) over 4 consecutive days. From these observations, 15 of these 33 diamidines were then further tested in vivo, using a single bolus dose for administration. The total cure of mice infected with T. congolense and T. vivax was seen with single i.p. doses of 5 and 2.5 mg/kg, respectively. This study identified a selection of diamidines which could be considered lead compounds for the treatment of nagana.

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In vitro and in vivo venom-inhibition assays identify metalloproteinase-inhibiting drugs as potential treatments for snakebite envenoming by Dispholidus typus

10.1101/2022.01.07.475313 ◽

2022 ◽

Author(s):

Stefanie K Menzies ◽

Rachel Hannah Clare ◽

Chunfang Xie ◽

Adam Westhorpe ◽

Steven R Hall ◽

...

Keyword(s):

Treatment Options ◽

Sub Saharan Africa ◽

Consumption Coagulopathy ◽

Survival Times ◽

Clotting Factors ◽

Metalloproteinase Inhibitors ◽

The Matrix ◽

Sub Saharan

Snakebite envenoming affects more than 250,000 people annually in sub-Saharan Africa. Envenoming by Dispholidus typus (boomslang) results in venom induced consumption coagulopathy, whereby highly abundant prothrombin-activating snake venom metalloproteinases (SVMPs) consume clotting factors and deplete fibrinogen. The only available treatment for D. typus envenoming is the monovalent SAIMR Boomslang antivenom. Treatment options are urgently required because this antivenom is often difficult to source and, at $6,000/vial, typically unaffordable for most snakebite patients. We therefore investigated the in vitro and in vivo preclinical efficacy of four SVMP inhibitors to neutralise the effects of D. typus venom; the matrix metalloproteinase inhibitors marimastat and prinomastat, and the metal chelators dimercaprol and DMPS. The venom of D. typus exhibited an SVMP-driven procoagulant phenotype in vitro. Marimastat and prinomastat demonstrated equipotent inhibition of the SVMP-mediated procoagulant activity of the venom in vitro, whereas dimercaprol and DMPS showed considerably lower potency. However, when tested in preclinical murine models of envenomation, DMPS and marimastat demonstrated partial protection against venom lethality, demonstrated by prolonged survival times of experimental animals, whereas dimercaprol and prinomastat failed to confer any protection at the doses tested. The results presented here demonstrate that DMPS and marimastat show potential as novel small molecule-based therapeutics for D. typus snakebite envenomation. These two drugs have been previously shown to be effective against Echis ocellatus venom induced consumption coagulopathy (VICC) in preclinical models, and thus we conclude that marimastat and DMPS may be valuable early intervention therapeutics to broadly treat VICC following snakebite envenoming in sub-Saharan Africa.

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