Metabolic Complications of Severe Malaria

Planche, Tim; Dzeing, Arnaud; Ngou-Milama, Édouard; Kombila, Maryvonne; Stacpoole, Peter W.

doi:10.1007/3-540-29088-5_5

Cited by 36 publications

(42 citation statements)

References 112 publications

(176 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Human insulin activates proteins associated with insulin signaling in the mosquito midgut, suggesting that the control of aging by IIS is evolutionarily conserved in the mosquito and that, as has been observed in C. elegans (Libina et al, 2003), the midgut may function as a signaling center for mosquito lifespan. In the light of the fact that hyperinsulinemia can be associated with human malaria infection (Planche et al, 2005), our data also suggest that the lifespan of mosquitoes in nature is directly regulated by this blood-derived hormone, perhaps to an even greater degree when human parasite infection is prevalent.…”

Section: Introductionmentioning

confidence: 68%

“…In mice, hypoglycemia has been causally linked to hyperinsulinemia (Elased and Playfair, 1996). In humans, malaria parasite infection and quinine therapy of infection can also lead to hyperinsulinemia (White et al, 1983;Planche et al, 2005). Average insulin levels in hyperinsulinemic malaria patients were 1.6ϫ10 ·mol·l -1 (White et al, 1983).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Insulin regulates aging and oxidative stress in Anopheles stephensi

Kang

Mott

Tapley

et al. 2008

Journal of Experimental Biology

View full text Add to dashboard Cite

SUMMARYObservations from nematodes to mammals indicate that insulin/insulin-like growth factor signaling (IIS) regulates lifespan. As in other organisms, IIS is conserved in mosquitoes and signaling occurs in multiple tissues. During bloodfeeding, mosquitoes ingest human insulin. This simple observation suggested that exogenous insulin could mimic the endogenous hormonal control of aging in mosquitoes, providing a new model to examine this phenomenon at the organismal and cellular levels. To this end, female Anopheles stephensi mosquitoes were maintained on diets containing human insulin provided daily in sucrose or three times weekly by artificial bloodmeal. Regardless of delivery route, mosquitoes provided with insulin at 1.7ϫ10 -4 and 1.7ϫ10 -3 ·mol·l -1 , doses 0.3-fold and 3.0-fold higher than non-fasting blood levels, died at a faster rate than controls. In mammals, IIS induces the synthesis of reactive oxygen species and downregulates antioxidants, events that increase oxidative stress and that have been associated with reduced lifespan. Insulin treatment of mosquito cells in vitro induced hydrogen peroxide synthesis while dietary supplementation reduced total superoxide dismutase (SOD) activity and manganese SOD activity relative to controls. The effects of insulin on mortality were reversed when diets were supplemented with manganese (III) tetrakis (4-benzoic acid) porphyrin (MnTBAP), a cell-permeable SOD mimetic agent, suggesting that insulin-induced mortality was due to oxidative stress. In addition, dietary insulin activated Akt/protein kinase B and extracellular signal-regulated kinase (ERK) in the mosquito midgut, suggesting that, as observed in Caenorhabditis elegans, the midgut may act as a ʻsignaling centerʼ for mosquito aging.

show abstract

Section: Introductionmentioning

confidence: 68%

Section: Introductionmentioning

confidence: 99%

Insulin regulates aging and oxidative stress in Anopheles stephensi

Kang

Mott

Tapley

et al. 2008

Journal of Experimental Biology

View full text Add to dashboard Cite

show abstract

“…One possibility is that parasitaemia may correlate negatively with blood quality, and that mosquitoes compensate for poorly nutritious blood by feeding more, which would result in higher infection levels. In human malaria, it is well established that peak parasitaemia is associated with decreased concentrations of several blood metabolites, including lipid and sugar levels [55]. In our experiments, the only measure of blood quality we recorded was the number of red blood cells, which are known to be an important source of protein for mosquitoes.…”

Section: (C) Virulence In Birds and Mosquito Transmissionmentioning

confidence: 91%

Avian malaria: a new lease of life for an old experimental model to study the evolutionary ecology ofPlasmodium

Pigeault

Vézilier

Cornet

et al. 2015

Phil. Trans. R. Soc. B

View full text Add to dashboard Cite

One contribution of 17 to a theme issue 'Within-host dynamics of infection: from ecological insights to evolutionary predictions'. Avian malaria has historically played an important role as a model in the study of human malaria, being a stimulus for the development of medical parasitology. Avian malaria has recently come back to the research scene as a unique animal model to understand the ecology and evolution of the disease, both in the field and in the laboratory. Avian malaria is highly prevalent in birds and mosquitoes around the world and is amenable to laboratory experimentation at each stage of the parasite's life cycle. Here, we take stock of 5 years of experimental laboratory research carried out using Plasmodium relictum SGS1, the most prevalent avian malaria lineage in Europe, and its natural vector, the mosquito Culex pipiens. For this purpose, we compile and analyse data obtained in our laboratory in 14 different experiments. We provide statistical relationships between different infection-related parameters, including parasitaemia, gametocytaemia, host morbidity (anaemia) and transmission rates to mosquitoes. This analysis provides a wide-ranging picture of the within-host and between-host parameters that may bear on malaria transmission and epidemiology.

show abstract

“…In mice, hypoglycemia has been functionally linked to hyperinsulinemia (Elased and Playfair, 1996). In humans, malaria parasite infection and quinine therapy can precipitate hyperinsulinemia (White et al, 1983;Planche et al, 2005). Insulin levels in hyperinsulinemic malaria patients were 1.6×10 mmoll -1 (White et al, 1983).…”

Section: Introductionmentioning

confidence: 99%

Human IGF1 extends lifespan and enhances resistance to Plasmodium falciparum infection in the malaria vector Anopheles stephensi

Drexler

Nuss

Hauck

et al. 2013

Journal of Experimental Biology

View full text Add to dashboard Cite

SUMMARYThe highly conserved insulin/insulin-like growth factor (IGF) signaling (IIS) pathway regulates metabolism, development, lifespan and immunity across a wide range of organisms. Previous studies have shown that human insulin ingested in the blood meal can activate mosquito IIS, resulting in attenuated lifespan and increased malaria parasite infection. Because human IGF1 is present at higher concentrations in blood than insulin and is functionally linked with lifespan and immune processes, we predicted that human IGF1 ingested in a blood meal would affect lifespan and malaria parasite infection in the mosquito Anopheles stephensi. Here we demonstrate that physiological levels of ingested IGF1, like insulin, can persist intact in the blood-filled midgut for up to 30h and disseminate into the mosquito body, and that both peptides activate IIS in mosquito cells and midgut. At these same levels, ingested IGF1 alone extended average mosquito lifespan by 23% compared with controls and, more significantly, when ingested in infected blood meals, reduced the prevalence of Plasmodium falciparum-infected mosquitoes by >20% and parasite load by 35-50% compared with controls. Thus, the effects of ingested IGF1 on mosquito lifespan and immunity are opposite to those of ingested insulin. These results offer the first evidence that insect cells can functionally discriminate between mammalian insulin and IGF1. Further, in light of previous success in genetically targeting IIS to alter mosquito lifespan and malaria parasite transmission, this study indicates that a more complete understanding of the IIS-activating ligands in blood can be used to optimize transgenic strategies for malaria control.

show abstract

Metabolic Complications of Severe Malaria

Cited by 36 publications

References 112 publications

Insulin regulates aging and oxidative stress in Anopheles stephensi

Insulin regulates aging and oxidative stress in Anopheles stephensi

Avian malaria: a new lease of life for an old experimental model to study the evolutionary ecology ofPlasmodium

Human IGF1 extends lifespan and enhances resistance to Plasmodium falciparum infection in the malaria vector Anopheles stephensi

Contact Info

Product

Resources

About