Snooki - fighting the good fight?

Okay, okay, first things first — no one reading this should run out and grab the Smirnoff in the name of hematologic health. (If you’re of legal drinking age and want to do shots responsibly for some other reason, that’s your business.)

But it is worth noting the recent discovery that fruit flies like to get their buzz on (pun alert) to protect themselves against parasites trying to take up residence in their blood. While there’s quite a bit of difference between us and fruit flies, it’s definitely worth considering whether we or other organisms could derive similar benefits from alcohol consumption in the fight against certain blood-borne diseases.

Besides, if you get a little crazy on Thirsty Thursday and you have to explain your splitting headache to your boss on Friday, this post might give you a new excuse to try.

[But no, really, drink responsibly.]

There are a million reasons I can think of to pity fruit flies, but the latest one is this: certain types of wasps try to deposit their eggs in fruit flies’ babies, in hopes that the baby wasps will hatch and eat the baby fruit flies from the inside out, enabling a well-fed adult wasp to emerge. Here’s a visual, to make this sadder:

Sucks. Can you imagine how the fruit fly parents of that fruit fly larva must be feeling??? No, no you can’t.

But take heart, dear reader! Those fruit fly larvae are not as defenseless as they may seem. In fact, they’ve evolved for just such occasions. You know how those tiny flies start to hover around your fruit basket when it’s been out for more than a few days? Those are fruit flies, and their larvae often live off of rotting fruit that can have over 5% alcohol content due to fermentation.

Researchers at Emory University decided to put some larvae on a 6% alcohol diet, and others on a 0% alcohol diet. The larvae on the 6% alcohol diet survived wasp infection 60% of the time, while none of the larvae on a nonalcoholic diet lived once infected. In other words, baby fruit flies that are drunk out of their minds are way better at surviving attacks by parasites. Wasps are not adapted to the high alcohol content of rotting, fermented fruit, so when they try to lay their eggs in fruit fly larvae that have gorged themselves on 5% alcohol all day, those eggs just don’t stand a chance.

Since humans have not evolved to eat rotten fruit all day and detoxify that much alcohol, we probably shouldn’t run out and get hammered when we’re trying to avoid malaria. However, it could be in our interests for someone to look into the potential benefits of moderate alcohol consumption in fighting parasite infection…any volunteers?

Bottoms up!

Milan NF, Kacsoh BZ, & Schlenke TA (2012). Alcohol Consumption as Self-Medication against Blood-Borne Parasites in the Fruit Fly. Current biology : CB, 22 (6), 488-93 PMID: 22342747

The research described in this article identifies a new potential way to target the ability of malaria parasites to hijack red blood cells for their own use.

Title: Malaria parasite clag3 genes determine channel-mediated nutrient uptake by infected red blood cells

Authors: Wang Nguitragool, Abdullah A.B. Bokhari, Ajay D. Pillai, Kempaiah Rayavara, Paresh Sharma, Brad Turpin, L. Aravind and Sanjay A. Desai

Date of publication: May 26, 2011

Direct link: http://www.cell.com/retrieve/pii/S0092867411005241

PMID: 21620134

Abstract: In order for malaria parasites to replicate inside of red blood cells, the parasites force the cells to take up increased amounts of nutrients. This is a conserved feature across diverse malaria parasite species and thus is an opportune drug target. It has been unclear exactly how the parasite forces the cell to take up more nutrients, although past studies have shown that the nutrients are taken in through some kind of channel — but is the channel already present in the red blood cells and waiting for activation, or did the parasites put them there? The best candidate for a channel made by parasites and inserted into red blood cells is a channel called the plasmodial surface anion channel (PSAC). These authors use genetic analysis to find a family of parasite genes that regulate PSAC, and this work also includes a screen for drugs that inhibit this channel — presumably, these drugs have the potential for stopping malaria parasites from taking advantage of red blood cells.

Methods: The researchers performed a chemical screen for drugs that would inhibit PSAC activity in cells infected with malaria parasites and two drugs, ISPA-28 and ISPA-43, are followed up. Genetic studies were done to identify and assess two related parasite genes, clag3.1 and clag3.2, that have a role in PSAC activity.

Results: This paper is perhaps more complex than the others I’ve featured, and I will try to only include the most salient points. The authors screened chemical compounds for any that would inhibit PSAC activity, and they tested this using cells infected with two different strains of malaria parasite. Conveniently, the compound ISPA-28 inhibited the channels for one strain significantly more than for the other, meaning that the two strains could be compared for genetic differences that might help explain how the channel works. It turned out that expression of one version of a gene versus another, clag3.1 versus clag3.2, determined whether the drug was effective at inhibiting PSAC. The authors even found another drug from their screen, ISPA-43, that had the opposite inhibition pattern of ISPA-28. This is to say that ISPA-28 inhibits the channels of parasites expressing clag3.1 and ISPA-43 inhibits the channels of parasites expressing clag3.2. More work needs to be done to fully explain how these genes interact with the PSAC channel to alter its susceptibility to these drugs, but the authors did find that the proteins encoded by these genes end up at the surface of red blood cells, where the channel is located.

Bottom line: These authors have found two versions of the same gene in some malaria parasites that can determine whether the parasite will be affected by a particular drug or not. Specifically, one of two drugs will inhibit the channel that lets nutrients into red blood cells during parasite infection, depending on which of two gene versions is present. Essentially, this work opens the door to a whole new world of ways to potentially treat malaria infections — by developing drugs and vaccines against the PSAC channel. Additionally, knowing which genes lend susceptibility to which drugs would mean that the parasites from infected persons could be screened to select the best treatment for the patient.

 
Nguitragool W, Bokhari AA, Pillai AD, Rayavara K, Sharma P, Turpin B, Aravind L, & Desai SA (2011). Malaria Parasite clag3 Genes Determine Channel-Mediated Nutrient Uptake by Infected Red Blood Cells. Cell, 145 (5), 665-77 PMID: 21620134

Photo credit: http://scienceblogs.com