Researchers discover surprising drug that blocks malaria

Jan 16, 2007

Northwestern University researchers have discovered how malaria parasites persuade red blood cells to engulf them -- and how to block the invading parasites. The malaria marauders hack into the red cell's signaling system and steal the molecular equivalent of its password to spring open the door to the cell. But researchers have found that a common blood pressure medication – propranolol – jams the signal to prevent the parasite from breaking in.

Scientists had long been perplexed by malaria's ability to hijack red blood cells, then wildly multiply and provoke its life-threatening symptoms.

"This opens the possibility for important new drugs for malaria that won't become resistant. New drugs are urgently needed because the parasite has evolved resistance against virtually all types of commonly used drugs," said Kasturi Haldar, principal investigator for the study and the Charles E. and Emma H. Morrison Professor in the department of pathology at the Feinberg School of Medicine at Northwestern. Sean Murphy, a Medical Sciences Training Program student, is the study's lead author.

The study was published in PLoS Medicine.

Malaria, one of the top three deadliest diseases in the developing world, is resurging worldwide because of drug resistance and the lack of an effective vaccine, Haldar said. Jamaica recently reported an outbreak of malaria after it had been eradicated in that country for 50 years.

A blood-borne illness, malaria is transmitted by infected mosquitoes. The symptoms include high fevers and flu-like symptoms such as chills, headache, muscle aches and fatigue. The disease kills an estimated 2 million people a year, mostly African children under five. It also poses a risk to travelers. An estimated 500 million cases of malaria were expected in 2006.

Commonly used drugs against malaria attack the parasite, but it rapidly changes its molecular structure to become resistant to those drugs. It would be difficult, however, for the malaria parasite to develop resistance to a drug that acts on a person's red blood cells as the blood pressure medication does, Haldar said.

When Haldar and her colleagues tested propranolol in combination with existing anti-malarial drugs in human cell cultures and mice, it reduced the dose of the anti-malarial drugs needed to kill the parasites by tenfold. That's significant because high doses of anti-malarial drugs – increasingly necessary as resistance to them builds -- can be toxic. In addition, blood pressure medication like propranolol is cheap and safe for use even in pregnant women, a group particularly vulnerable to malaria.

"We're working on developing a unique drug that would combine anti-malarial drugs with blood pressure medication. We think it has a high likelihood of success," Haldar said. The next step is human clinical trials.

Source: Northwestern University

Explore further: Radical vaccine design effective against herpes viruses

add to favorites email to friend print save as pdf

Related Stories

Nanotechnology against malaria parasites

Dec 09, 2014

Malaria parasites invade human red blood cells, they then disrupt them and infect others. Researchers at the University of Basel and the Swiss Tropical and Public Health Institute have now developed so-called ...

Recommended for you

Radical vaccine design effective against herpes viruses

5 hours ago

Herpes simplex virus infections are an enormous global health problem and there is currently no viable vaccine. For nearly three decades, immunologists' efforts to develop a herpes vaccine have centered on ...

Popular antioxidant likely ineffective, study finds

14 hours ago

The popular dietary supplement ubiquinone, also known as Coenzyme Q10, is widely believed to function as an antioxidant, protecting cells against damage from free radicals. But a new study by scientists at McGill University ...

New findings on 'key players' in brain inflammation

15 hours ago

Inflammation is the immune system's natural reaction to an 'aggressor' in the body or an injury, but if the inflammatory response is too strong it becomes harmful. For example, inflammation in the brain occurs ...

Gut microbial mix relates to stages of blood sugar control

Mar 05, 2015

The composition of intestinal bacteria and other micro-organisms—called the gut microbiota—changes over time in unhealthy ways in black men who are prediabetic, a new study finds. The results will be presented Friday ...

User comments : 0

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.