The Immunomodulatory Effect of Sambucol on Leishmanial and Malarial Infections
ABSTRACT A nontoxic dose of Sambucol, an immunomodulator commercially sold as an immune stimulator, was examined in murine models of leishmaniasis and malaria. Sambucol causes a shift in the immune response, as demonstrated in human monocyte cultures, to Th1 (inflammation-associated) responses. Treatment of leishmania-infected mice with Sambucol delayed the development of the disease. As there was no direct IN VITRO anti-leishmanial effect, the observed partial protection IN VIVO is most likely related to immune modulation. Although increased Th1 responses are associated with protection from leishmaniasis, they are considered to be the main immunopathological processes leading to cerebral malaria. Administration of Sambucol to mice prior to and following infection with Plasmodium berghei ANKA increased the incidence of cerebral malaria, while administration of Sambucol after infection had no effect on the disease. The results demonstrate how an inflammatory-like response may alleviate or exacerbate clinical symptoms of disease and hint at the importance of administration timing. The overall effect of immunomodulator administration depends on the ongoing immune response and the Th1/Th2 balance determined by both host and parasite defense mechanisms.
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ABSTRACT: Himatanthus sucuuba (HsL) latex exhibited a potent leishmanicidal activity against intracellular amastigotes of Leishmania amazonensis, a causative agent of cutaneous leishmaniasis. HsL inhibited intracellular amastigote growth in a dose-dependent manner (IC(50)=15.7microg/mL). Moreover, HsL increased nitric oxide (NO) and Tumor Nuclear Factor-alpha (TNF-alpha) and decreased Transforming Growth Factor-beta (TGF-beta) production in macrophages. As assessed by plasma membrane integrity and mitochondrial activity, HsL showed low toxicity for host macrophages. HsL in vivo was active by the oral route, reducing the parasite load in established footpad lesions after only five doses. In summary, these findings support HsL as an interesting candidate for further evaluations regarding its potential application as a therapeutical agent against Leishmania.Parasitology International 06/2010; 59(2):173-7. DOI:10.1016/j.parint.2010.01.002 · 2.11 Impact Factor
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ABSTRACT: From antiquity up into the 20th century tertian and quartan malaria which are caused by the parasites Plasmodium vivax and Plasmodium malariae were widespread in Central Europe. Hundreds of different remedies against malaria can be found in herbals from the Renaissance. To document and discuss from a modern pharmacological viewpoint the old remedies described in eight 16th and 17th century herbals written in German. Eight of the most important herbals of the 16th and 17th century including Bock (1577), Fuchs (1543), Matthiolus (1590), Lonicerus (1560), Brunfels (1532), Zwinger (1696), and Tabernaemontanus (1591 and 1678) were searched for terms related to malaria, and documented plants and recipes described for its treatment. Additionally the overlapping of these remedies with those in De Materia Medica by the Greek physician Dioscorides was studied. Three hundred and fourteen taxa were identified in the herbals for this indication. Recent pharmacological data was found for just 5% of them. The influence of De Materia Medica was shown to be negligible with only 3.5% of the remedies in common. European Renaissance herbals may be a valuable source of information for the selection of plants for focussed antiplasmodial screening programmes, but have received only little scientific attention. Antimalarial remedies from these herbals must be viewed as independent sources of knowledge separate from Dioscorides' De Materia Medica.Journal of ethnopharmacology 11/2010; 133(2):278-88. DOI:10.1016/j.jep.2010.10.060 · 2.94 Impact Factor
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ABSTRACT: This paper examines cellular and molecular mechanisms that may underpin the purported effects of five herbal supplements in the context of athlete immune function. Ginseng and echinacea are used frequently by athletes, whereas astragalus and elderberry are used infrequently and pequi is just emerging as a possible supplement. In vivo studies of these products on athlete immune function have yielded heterogeneous results, likely due to experimental design differences. Ginseng, echinacea, elderberry, and pequi are considered asterids sensu lato. Ginseng appears to exert strongest effects on components of adaptive immunity, in particular maintaining Th1/Th2 balance of CD4+T cells and their downstream effects, via its ginsenosides, flavonoids, and polysaccharides. Echinacea alkamides, caffeic acid derivatives, and polysacchardies may target both innate and adaptive immunity, though perhaps the former more consistently. Elderberry harbors anthocyanins and lectins which may modulate innate immunity. Data on pequi is limited but suggests that carotenoids, phenols, and fatty acids may alter circulating leukocyte populations. More phylogenetically distant, astragalus is a rosid sensu lato and may influence the innate immune system through flavonoids, polysaccharides, and saponins. Supplements generally demonstrate no effects on physiologic parameters such as lactate, oxygen dynamics, or athletic performance. Bioavailability studies indicate that purported bioactive molecules of these supplements may reach circulation in low but therapeutically-relevant quantities. Difficulties in crosscomparisons due to study design differences, coupled with an overall dearth of research on the topic, currently hamper any formal conclusions regarding the efficacy of these supplements as immunoregulators for athletes.02/2013; 8(1):78-100. DOI:10.1007/s11515-012-1197-z