FrogHeart

It’s known that grapefruit, despite its health benefits, can inhibit (or even a pose danger) to a medication’s effectiveness. Most of us have been warned at one time or another to avoid grapefruit juice when downing a pill. So, the news from the University of Louisville (Kentucky; UofL) about grapefruit as part of a drug delivery system seems a little counter-intuitive (from the May 22, 2013 news item on Azonano),

Grapefruits have long been known for their health benefits, and the subtropical fruit may revolutionize how medical therapies like anti-cancer drugs are delivered to specific tumor cells.

University of Louisville researchers have uncovered how to create nanoparticles using natural lipids derived from grapefruit, and have discovered how to use them as drug delivery vehicles. UofL scientists Huang-Ge Zhang, D.V.M., Ph.D., Qilong Wang, Ph.D., and their team today (May 21, 2013), published their findings in Nature Communications.

The May 21, 2013 University of Louisville news release by Julie Heflin, which originated the news item, describes how the nanoparticles are derived and their advantages,

“These nanoparticles, which we’ve named grapefruit-derived nanovectors (GNVs), are derived from an edible plant, and we believe they are less toxic for patients, result in less biohazardous waste for the environment and are much cheaper to produce at large scale than nanoparticles made from synthetic materials,” said Zhang, who holds the Founders Chair in Cancer Research at the Brown Cancer Center.

The researchers demonstrated that GNVs can transport various therapeutic agents, including anti-cancer drugs, DNA/RNA and proteins such as antibodies. Treatment of animals with GNVs seemed to cause less adverse effects than treatment with drugs encapsulated in synthetic lipids.

“Our GNVs can be modified to target specific cells — we can use them like missiles to carry a variety of therapeutic agents for the purpose of destroying diseased cells,” he said. “Furthermore, we can do this at an affordable price.”

The therapeutic potential of grapefruit derived nanoparticles was further validated through a Phase 1 clinical trial for treatment of colon cancer patients. So far, researchers have observed no toxicity in the patients who orally took the anti-inflammatory agent curcumin encapsulated in grapefruit nanoparticles.

The UofL scientists also plan to test whether this technology can be applied in the treatment of inflammation related autoimmune diseases like rheumatoid arthritis.

Here’s a link to and a citation for the researchers’ paper,

Delivery of therapeutic agents by nanoparticles made of grapefruit-derived lipids by Qilong Wang, Xiaoying Zhuang, Jingyao Mu, Zhong-Bin Deng, Hong Jiang, Xiaoyu Xiang, Baomei Wang, Jun Yan, Donald Miller, & Huang-Ge Zhang. Nature Communications 4, 1867 doi:10.1038/ncomms2886 Published 21 May 2013

This paper is behind a paywall.

As for the dangers of grapefruit-medication interactions, ABC (American Broadcasting Corporation) has a Nov. 26, 2012 news item featuring then new research suggesting that even more medications are affected by grapefruit/grapefruit juice than had previously been believed,

It has long been known that grapefruit juice can pose dangerous — and even deadly — risks when taken along with certain medications. Now, experts warn the list of medications that can result in these interactions is longer than many may have believed.

…

In a new report released Monday in the Canadian Medical Association Journal [CMAJ], researchers at the University of Western Ontario said that while 17 drugs were identified in 2008 as having the potential to cause serious problems when taken with grapefruit, this number has now grown to 43.

…

So how does a common breakfast fruit cause these problems? Grapefruits contain chemicals called furanocoumarins that interfere with how your body breaks down drugs before they enter the bloodstream. By preventing this normal breakdown of a drug, these chemicals in grapefruit can effectively cause a drug overdose and more severe side-effects.

Among the side effects sometimes seen with grapefruit-induced overdoses are heart rhythm problems, kidney failure, muscle breakdown, difficulty with breathing and blood clots. …

ABC provides a list of drugs that are affected by grapefruit here.

For interested parties, here’s a link to and a citation for the research on grapefruit-medication interactions,

Grapefruit–medication interactions: Forbidden fruit or avoidable consequences? by David G. Bailey, George Dresser, and J. Malcolm O. Arnold. CMAJ March 5, 2013 185:309-316; published ahead of print November 26, 2012,

This paper is behind a paywall.

I have a couple of final comments. (1) It would seem that the grapefruit’s characteristics at the macroscale are not echoed at the nanoscale. (2) Interestingly, the grapefruit nanoparticles (grapefruit nanovectors [GNVs]) are being used to encapsulate curcumin (a constituent of turmeric). I wrote about turmeric and its healing properties in a Dec. 26, 2011 posting, which features a number of links to research in this area.