The effect of dietary antioxidant supplementation in a vertebrate host on the infection dynamics and transmission of avian malaria to the vector

Abstract

Host susceptibility to parasites is likely to be influenced by intrinsic factors, such as host oxidative status determined by the balance between pro-oxidant production and antioxidant defences. As a result, host oxidative status acts as an environmental factor for parasites and may constrain parasite development. We evaluated the role of host oxidative status on infection dynamics of an avian malarial parasite by providing canaries (Serinus canaria) with an antioxidant supplementation composed of vitamin E (a lipophilic antioxidant) and olive oil, a source of monounsaturated fatty acids. Another group received a standard, non-supplemented food. Half of the birds in each group where then infected with the haemosporidian parasite, Plasmodium relictum. We monitored the parasitaemia, haematocrit level, and red cell membrane resistance, as well as the transmission success of the parasite to its mosquito vector, Culex pipiens. During the acute phase, the negative effect of the infection was more severe in the supplemented group, as shown by a lower haematocrit level. Parasitaemia was lower in the supplemented group during the chronic phase only. Mosquitoes fed on supplemented hosts were more often infected than mosquitoes fed on the control group. These results suggest that dietary antioxidant supplementation conferred protection against Plasmodium in the long term, at the expense of a short-term negative effect. Malaria parasites may take advantage of antioxidants, as shown by the increased transmission rate in the supplemented group. Overall, our results suggest an important role of oxidative status in infection outcome and parasite transmission.Electronic supplementary materialThe online version of this article (10.1007/s00436-018-5869-8) contains supplementary material, which is available to authorized users.

Differential Effect of Antioxidants Glutathione and Vitamin C on the Hepatic Injuries Induced by Plasmodium berghei ANKA Infection

“…Results demonstrated that treatment with GSH accelerates the evolution of the disease in PbA-infected mice as well as the liver damage, while the treatment with vitamin C controls the disease outcome and mitigates the hepatotoxicity associated with the condition. It is widely described in literature that human malaria is characterized by intense hepatotoxicity and liver dysfunction, and although hepatic dysfunction in malaria is not fully understood, oxidative stress is often related to this condition [17]. As demonstrated in both human patients and animals models, liver damage during Plasmodium infection occurs as a result of free heme accumulation that triggers severe oxidative stress and stimulates proinflammatory response by tumor necrosis factor (TNF-α) release [27][28][29].…”

“…Previous studies demonstrate that liver injuries caused by Plasmodium infection are associated with unbalance of the antioxidant system in hepatocytes [ 17 ]. However, it remains unclear if treatment with antioxidants is able to protect the liver of infected subjects.…”

Mediterranean Diet: Lipids, Inflammation, and Malaria Infection

“…An insecticide comprising straight-chain octanoic, nonanoic, and decanoic saturated fatty acids (C8, C9, and C10) called C8910, displayed insecticidal effects on different strains of Anopheles funestus [ 152 ]. Supplemented birds with olive oil and vitamin E increased the transmission to the vector, indicating that vertebrate host oxidative status influences parasite transmission to the vector [ 153 ].…”

Ecophysiological assessment of blood haemosporidian infections in birds

“…1). Varios estudios han relacionado la presencia de hemosporidios con niveles bajos de hematocrito (Booth y Elliott 2002;Delhaye et al 2018), pudiendo ser consecuencia de una anemia hemolítica severa (Desser y Bennett 1993;Palinauskas et al 2011).…”