Towards identifying novel anti-Eimeria agents: trace elements, vitamins, and plant-based natural products

Abstract

Eimeriosis, a widespread infectious disease of livestock, is caused by coccidian protozoans of the genus Eimeria. These obligate intracellular parasites strike the digestive tract of their hosts and give rise to enormous economic losses, particularly in poultry, ruminants including cattle, and rabbit farming. Vaccination, though a rational prophylactic measure, has not yet been as successful as initially thought. Numerous broad-spectrum anti-coccidial drugs are currently in use for treatment and prophylactic control of eimeriosis. However, increasing concerns about parasite resistance, consumer health, and environmental safety of the commercial drugs warrant efforts to search for novel agents with anti-Eimeria activity. This review summarizes current approaches to prevent and treat eimeriosis such as vaccination and commercial drugs, as well as recent attempts to use dietary antioxidants as novel anti-Eimeria agents. In particular, the trace elements selenium and zinc, the vitamins A and E, and natural products extracted from garlic, barberry, pomegranate, sweet wormwood, and other plants are discussed. Several of these novel anti-Eimeria agents exhibit a protective role against oxidative stress that occurs not only in the intestine of Eimeria-infected animals, but also in their non-parasitized tissues, in particular, in the first-pass organ liver. Currently, it appears to be promising to identify safe combinations of low-cost natural products with high anti-Eimeria efficacy for a potential use as feed supplementation in animal farming.

Antimalarial and antioxidant activities of Indigofera oblongifolia on Plasmodium chabaudi-induced spleen tissue injury in mice

“…. Clearance of malaria parasites appears to be mediated by both acquired and innate immune responses (Wunderlich et al 2014). Female C57BL/6 mice were able to heal infections with P. chabaudi and to develop long-lasting immunity against homologous rechallenge (Dkhil 2009).…”

“…Cytokines in malaria are reported to be important molecular markers of cell-mediated immune response and known to be critical players in the regulation of disease. Several studies have shown cytokines to be associated differentially with appearance of disease symptoms, levels of parasitemia, and with disease severity and complications (Malaguarnera and Musumeci 2002;Wunderlich et al 2014). The inflammatory response that is needed to remove parasites leads to considerable tissue damage, and activation of phagocytes to kill intracellular or extracellular parasites requires the production of inflammatory cytokines.…”

Anticoccidial and antioxidant activities of zinc oxide nanoparticles on Eimeria papillata-induced infection in the jejunum

“…2 Zinc oxide nanoparticles (ZNPs) represent one such nanotechnological approach, and are characterized by their high catalytic efficiency and high adsorbing ability. 3 Moreover, zinc is considered to be an essential trace element for various cellular activities 4 and is a part of more than 200 enzymes. 5 Recently, Ahmadi et al 6 reported that dietary ZNPs improved oxidant state and had positive effect on the activity of several serum enzymes.…”

“…7 More generally, it is recognized that dietary trace elements/ antioxidants can help maintain an appropriate antioxidant balance in the case of many infections. 28 Wunderlich et al 4 for example, reported that zinc is fundamentally important for a balanced redox state, for the immune system, as well as for growth and development. More recently, Shoae-Hagh et al 29 reported that ZNPs reduce apoptosis and oxidative stress values in isolated rat pancreatic islets.…”

Nanosizing Cynomorium: Thumbs up for Potential Antifungal Applications

“…Although modern chemical and biological techniques such as combinatorial chemistry and library-based automated screening have, at some point, eclipsed the more down-to-earth hunt for exotic natural products in equally exotic places, the last decade has witnessed a renewed interest in plant-based natural products [2,3]. This renaissance of the natural product has been fuelled in part by the emergence of drug-resistant pathogens, but also by a need for "milder" drugs, to treat, for instance, an ageing population over longer time periods and also against less aggressive pathogens.…”