Human insulin suppresses mosquito immune system: Increasing cases of type 2 diabetes could abet malaria's spread

June 19, 2012

Human insulin suppresses the mosquito immune system, according to a paper in the June Infection and Immunity. And while mosquitoes and malaria might seem to go together like baseball and hotdogs, mosquitoes' immunological resistance to the malaria parasite actually slows its spread among H. sapiens.

"A fair portion actually fight off the infection," says first author Nazzy Pakpour of the University of California, Davis.

But now the rate of is climbing in Africa as in most of the rest of the world, to the point where by 2030, one in five adults there are predicted to be so-afflicted. More diabetes means more hyperinsulinemia—more human insulin to inhibit mosquitoes' immune response to Plasmodium falciparum, thus aiding and abetting transmission of this dread disease.

As horrific as the medical consequences of all this might be, the science is intriguing. "It's crazy to think something in our blood could change how mosquitoes respond to parasites," says Pakpour.

In earlier work, Pakpour and collaborators showed that ingested human insulin activates the insulin/IGF-1 signaling pathway in Anopheles stephensi , making them more vulnerable to invasion by P. falciparum. The new study showed that insulin signaling reduced expression of certain mosquito immunity genes that are under the same regulatory control, and that human insulin suppressed mosquito immunity by activating the so-called PI3K signaling pathway, and that artificially inhibiting that pathway could reverse the immunosuppressive effects of human insulin.

Explore further: Wolbachia bacteria reduce parasite levels and kill the mosquito that spreads malaria

More information: N. Pakpour, V. Corby-Harris, G.P. Green, H.M. Smithers, K.W. Cheung, M.A.Riehle, and S. Luckhart, 2012. Ingested human insulin inhibits the mosquito NF-KAPPAB-dependent immune response to Plasmodium falciparum. Infect. Immun. 80:2141-2149. Download the journal article at http://bit.ly/asm061912a

Related Stories

Wolbachia bacteria reduce parasite levels and kill the mosquito that spreads malaria

May 19, 2011
Wolbachia are bacteria that infect many insects, including mosquitoes. However, Wolbachia do not naturally infect Anopheles mosquitoes, which are the type that spreads malaria to humans. Researchers at the Johns Hopkins Bloomberg ...

Scientists engineer mosquito immune system to fight malaria

December 22, 2011
Researchers at the Johns Hopkins Malaria Research Institute have demonstrated that the Anopheles mosquito's innate immune system could be genetically engineered to block the transmission of malaria-causing parasites to humans. ...

Certain bacteria render mosquitoes resistant to deadly malaria parasite

May 12, 2011
cientists have identified a class of naturally occurring bacteria that can strongly inhibit malaria-causing parasites in Anopheles mosquitoes, a finding that could have implications for efforts to control malaria. The study, ...

Recommended for you

Immune system can be modulated by targeted manipulation of cell metabolism

August 21, 2017
In its attempt to fight a serious bacterial infection, caused by listeria, for example, the immune system can become so over-activated that the resulting inflammatory response and its consequences can quickly lead to death. ...

Australian researchers in peanut allergy breakthrough

August 17, 2017
Australian researchers have reported a major breakthrough in the relief of deadly peanut allergy with the discovery of a long-lasting treatment they say offers hope that a cure will soon be possible.

Genetic variants found to play key role in human immune system

August 16, 2017
It is widely recognized that people respond differently to infections. This can partially be explained by genetics, shows a new study published today in Nature Communications by an international collaboration of researchers ...

Study identifies a new way to prevent a deadly fungal infection spreading to the brain

August 16, 2017
Research led by the University of Birmingham has discovered a way to stop a deadly fungus from 'hijacking' the body's immune system and spreading to the brain.

Biophysics explains how immune cells kill bacteria

August 16, 2017
(Tokyo, August 16) A new data analysis technique, moving subtrajectory analysis, designed by researchers at Tokyo Institute of Technology, defines the dynamics and kinetics of key molecules in the immune response to an infection. ...

How a nutrient, glutamine, can control gene programs in cells

August 15, 2017
The 200 different types of cells in the body all start with the same DNA genome. To differentiate into families of bone cells, muscle cells, blood cells, neurons and the rest, differing gene programs have to be turned on ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.