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

Breast milk found to protect against food allergy

November 20, 2017
Eating allergenic foods during pregnancy can protect your child from food allergies, especially if you breastfeed, suggests new research from Boston Children's Hospital. The study, published online today in the Journal of ...

Zika-related nerve damage caused by immune response to the virus

November 20, 2017
The immune system's response to the Zika virus, rather than the virus itself, may be responsible for nerve-related complications of infection, according to a Yale study. This insight could lead to new ways of treating patients ...

How a poorly explored immune cell may impact cancer immunity and immunotherapy

November 17, 2017
The immune cells that are trained to fight off the body's invaders can become defective. It's what allows cancer to develop. So most research has targeted these co-called effector T-cells.

Asthma attacks reduced in tree-lined urban neighborhoods

November 17, 2017
People living in polluted urban areas are far less likely to be admitted to hospital with asthma when there are lots of trees in their neighbourhood, a study by the University of Exeter's medical school has found.

How the immune system identifies invading bacteria

November 16, 2017
The body's homeland security unit is more thorough than any airport checkpoint. For the first time, scientists have witnessed a mouse immune system protein frisking a snippet of an invading bacterium. The inspection is far ...

Can asthma be controlled with a vitamin supplement?

November 16, 2017
The shortness of breath experienced by the nearly 26 million Americans who suffer from asthma is usually the result of inflammation of the airways. People with asthma typically use albuterol for acute attacks and inhaled ...

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.