Statin, osteoporosis drug combo may help treat parasitic infections

October 17, 2013 by James Hataway

Researchers at the University of Georgia have discovered that a combination of two commonly prescribed drugs used to treat high cholesterol and osteoporosis may serve as the foundation of a new treatment for toxoplasmosis, a parasitic infection caused by the protozoan Toxoplasma gondii. They published their findings recently in PLOS Pathogens.

Toxoplasma gondii is a parasite capable of infecting nearly all warm-blooded animals. While healthy human adults usually suffer no lasting ill effects from infection, it can be harmful or fatal to unborn fetuses or those with .

"For many years, therapies for toxoplasmosis have focused on drugs that target only the parasite," said Silvia Moreno, senior author of the article and professor of cellular biology in UGA's Franklin College of Arts and Sciences. "But in this paper, we show how we can hit the parasite with two drugs simultaneously, one that affects body chemistry in the host and one that affects the parasite."

The UGA researchers discovered that a combination of the cholesterol lowering drug atorvastatin and osteoporosis medication , both more commonly known by their respective trade names, Lipitor and Zometa, produce changes in the mammalian host and in the parasite that ultimately block parasite replication and spread of the infection.

"These two drugs have a strong synergy," said Moreno, who is also a member of UGA's Center for Tropical and Emerging Global Diseases. "The mice we treated were cured from a lethal infection using this combination approach."

Moreno and her colleagues began working on this drug combination following a series of experiments with unexpected results. They created a genetically modified version of the parasite in the laboratory that lacked a specific enzyme essential for one of the organism's most basic functions.

They thought such an experiment was an excellent opportunity to observe how the absence of this enzyme would kill the parasites. But every time they checked on the supposedly defective parasites, they were healthy and appeared completely unaffected.

"We kept asking ourselves, 'How did this happen? This enzyme should be essential to the parasite's survival,'" said Zhu-Hong Li, a UGA research scientist and lead author of the article. "It's almost like a human surviving without food or air."

What they discovered is that in order to survive, Toxoplasma has evolved an extraordinary ability to siphon essential compounds from its host when it is unable to make them on its own. This led them to the two-drug therapy.

Zoledronic acid prevents synthesis in the parasite and atorvastatin inhibits production in the host.

When Toxoplasma cannot produce these important molecules itself or steal them from its , the parasites die.

"These drugs have been studied extensively, they are FDA-approved and safe for most people," Moreno said. "Plus, one might not have to take the drugs for an extended period, just long enough to clear the ."

Moreno cautions that more research must be done before this becomes an accepted treatment for humans, but she hopes that a similar strategy might work for other serious parasitic diseases, such as malaria and cryptosporidiosis.

Early experiments with an anti-malarial drug already suggest that combining atorvastatin with fosmidomycin, an antibiotic effective against malaria , creates a more potent antimalarial cocktail and it may lessen the risk of resistance.

Explore further: Hitting parasites where they hurt: New research shows promise in the fight against Toxoplasmosis

Related Stories

Hitting parasites where they hurt: New research shows promise in the fight against Toxoplasmosis

May 21, 2012
Toxoplasmosis, a disease caused by the parasite Toxoplasma gondii, is one of the most common parasitic infections in the world. In the U.S. it is estimated that more than 22 percent of the population 12 years and older have ...

Toxoplasma-infected mice remain unafraid of cats even after parasite clearance

September 18, 2013
Chronic infection with the parasite Toxoplasma gondii can make mice lose their innate, hard-wired fear of cats. This loss of their innate fear may persist after the parasite is no longer detectable in their brains, suggesting ...

Researchers discover potential new mechanisms of drug resistance in Toxoplasma

June 21, 2011
Scientists have for years been puzzled by why drugs are sometimes effective in treating parasitic diseases, while other times they have little or no effect.

Malaria, toxoplasmosis: Toward new lines of research?

October 10, 2013
A study realized by teams from the Institut Pasteur, the Institut Cochin and the Wellcome Trust Centre for Molecular Parasitology of the University of Glasgow, could redefine part of the present lines of research toward a ...

Malaria parasite protein identified as potential new target for drug treatment

April 25, 2013
Scientists have discovered how a protein within the malaria parasite is essential to its survival as it develops inside a mosquito. They believe their findings identify this protein as a potential new target for drug treatments ...

Recommended for you

Two Group A Streptococcus genes linked to 'flesh-eating' bacterial infections

September 22, 2017
Group A Streptococcus bacteria cause a variety of illnesses that range from mild nuisances like strep throat to life-threatening conditions including pneumonia, toxic shock syndrome and the flesh-eating disease formally known ...

Ecosystem approach makes urinary tract infection more treatable

September 22, 2017
The biological term 'ecosystem' is not usually associated with urinary tract infections, but this should change according to Wageningen scientists.

Residents: Frontline defenders against antibiotic resistance?

September 22, 2017
Antibiotic resistance continues to grow around the world, with sometimes disastrous results. Some strains of bacteria no longer respond to any currently available antibiotic, making death by infections that were once easily ...

Individualized diets for irritable bowel syndrome better than placebo

September 21, 2017
Patients with irritable bowel syndrome who follow individualized diets based on food sensitivity testing experience fewer symptoms, say Yale researchers. Their study is among the first to provide scientific evidence for this ...

Superbug's spread to Vietnam threatens malaria control

September 21, 2017
A highly drug resistant malaria 'superbug' from western Cambodia is now present in southern Vietnam, leading to alarming failure rates for dihydroartemisinin (DHA)-piperaquine—Vietnam's national first-line malaria treatment, ...

A dose of 'wait-and-see' reduces unnecessary antibiotic use

September 21, 2017
Asking patients to take a 'wait-and-see' approach before having their antibiotic prescriptions filled significantly reduces unnecessary use, a University of Queensland study has shown.

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.