Red Wine May Protect Against Foodborne Norovirus: A Glass A Day Keeps Gastroenteritis At Bay?

Talking to you about the potential health benefits of red wine is kind of like beating a dead horse at this point, though I will remind you all that there has been a lot of research out there supporting the idea that red wine and it’s “parts” have many beneficial characteristics when it comes to human health.  Of course, not all research is so rosy, and there are contradictory papers out there refuting the idea that red wine is all that good for you, but the evidence supporting the positive benefits seems to be more than plentiful.

A new study has been published examining the anti-viral qualities of red wine, specifically whether or not red wine could provide protection against the foodborne norovirus responsible for acute gastroenteritis,

Eosinophilic gastroenteritis. Photo By  [CC-BY-2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons

Eosinophilic gastroenteritis. Photo By [CC-BY-2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons

which is the leading cause of non-bacterial outbreaks throughout the world.

There have been several studies looking at the effects of red wine on bacterial foodborne pathogens, showing that red wine provides some protection against Staphylococcus aureus, E-coli, Salmonella enterica, Salmonella typhimurium, and Listeria monocytogenes.

In terms of anti-viral activity, red wine has been shown to provide protection against the herpes simplex virus, the varicella zoster virus, the influenza virus, and the Epstein-Barr virus.  However, none of these viruses are foodborne viruses, a specific subset of viruses that has yet to be studied in terms of red wine’s potential protective health benefits.

According to the researchers of this new study, human norovirus (the leading cause of non-bacterial outbreaks in the world) can’t be cultured in the lab, the feline and mouse versions of the norovirus were tested in its place.

Norovirus.  Photo by GrahamColm at en.wikipedia [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC-BY-3.0 (http://creativecommons.org/licenses/by/3.0)], from Wikimedia Commons

Norovirus. Photo by GrahamColm at en.wikipedia [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC-BY-3.0 (http://creativecommons.org/licenses/by/3.0)], from Wikimedia Commons

The results, based off of the in-vitro laboratory cell culture experiments, indicated that red wine, and in particular the red wine compound resveratrol, greatly reduced the ability of both feline and mouse norovirus to infect healthy cells.  From these results, it can be inferred that red wine acts as a sort of “insurance policy” against the potential foodborne norovirus illness, as it seems to prevent the norovirus from proliferating and spreading throughout the system.

 

 

Some more detailed results….

  • Catechin and gallic acid were found to be the major polyphenols in the red wine studied (a 2007 red Bordeaux), though resveratrol was found to be more effective as an anti-viral compound even though it was found in much lower quantities in the wine.

o   Resveratrol showed dose-dependent protection against the feline and mouse norovirus, with a concentration of 7.7uM (uM = micromolar) causing mortality to 50% of the virus present in the experimental sample.  As a comparison, the 50% mortality rate of influenza when occurs at a much higher concentration of resveratrol (45uM).

o   Catechin at 100uM led to norovirus mortality of 24-27%.

o   Gallic acid at 100uM led to norovirus mortality of 33-51%.

o   Caffeic acid at 100uM led to norovirus mortality of 16-24%.

  • Looking a little closer at genetics, this study showed that red wine and resveratrol decreased RdRp gene expression, a gene that is responsible for replication of the virus.

o   So, if red wine reduces RdRp gene expression, this means that virus won’t be replicated!

How much red wine are we talking?

According to the results of this study, it took just 7.7uM of resveratrol to cause 50% mortality in the norovirus.  This means that half of the virus was wiped out from the very beginning just by a concentration of 7.7uM.

How does 7.7uM translate into glasses of red wine?  Well, let’s do some super quick math:

  • There is a wide range of resveratrol levels in different red wines, but one value that is known to be found in one glass of some red wines is 2.0mg per glass of wine.
  • To convert mg/L to a concentration of moles/L, we have to do some simple Stoichiometry using our known amount of resveratrol, the average volume of wine in a single glass, and the molecular weight of resveratrol:

Equation1_the_academic_wino

  • The final step is to convert moles/L into umoles/L to reflect the same concentration mentioned in this paper:

equation2_the_academic_wino

So, using this theoretical glass of wine, with a resveratrol level of 2mg, one is getting a dose of 50uM/L, which is 6.5 times larger than the dose needed to cause a 50% mortality rate in the norovirus.

Now, we need to remember:  the exact noroviruses tested were the feline and mouse versions, though it is important to note that they are genetically very similar to the human norovirus, suggesting that the results are likely to carry over between species.

We also need to remember that this experiment was done in a controlled cell culture.  We’re missing

Photo By Jana Reifegerste (Flickr: Seeking Lavender (Provence 2012)) [CC-BY-SA-2.0 (http://creativecommons.org/licenses/by-sa/2.0)], via Wikimedia Commons

Photo By Jana Reifegerste (Flickr: Seeking Lavender (Provence 2012)) [CC-BY-SA-2.0 (http://creativecommons.org/licenses/by-sa/2.0)], via Wikimedia Commons

things like stomach acid, whatever else we happened to eat that day, and a variety of other complicating factors once you introduce the human digestive system.  So, while we see that in this study it only took 7.7uM of resveratrol to quell half of the norovirus, this value could very well change when you add the more complicated environment that is the gut.

Based on these results, it appears as though a glass of wine (and maybe even less!) may very well be protective against the proliferation and spread of foodborne norovirus.  All the more reason to have a glass of red wine with your meal!  Cheers!

I encourage all of you to share your thoughts!  Constructive comments welcome!

Source: Oh, M., Lee, J-H., Bae, S.Y., Seok, J.H., Kim, S., Chung, Y.B., Han, K.R., Kim, K.H., and Chung, M.S. 2015. Protective effects of red wine and resveratrol for foodborne virus surrogates. Food Control 47: 502-509.

2 comments for “Red Wine May Protect Against Foodborne Norovirus: A Glass A Day Keeps Gastroenteritis At Bay?

  1. WineKnurd
    August 20, 2014 at 8:57 am

    Hi Becca, its me again! Not making anymore lil’ Knurds just busy raising the one we got :)

    This article for me feels like the modern scientific justification of why the romans and medieval folk drank wine as opposed to water, due to its natural anti-bacterial and anti-viral capabilities, whether it be from sheer alcohol or other inhibitory compounds.

    Everyone knew they didn’t get sick when they drank wine, now we know more about why that is!

    • Becca
      August 20, 2014 at 10:07 am

      Glad to hear from you again! Your little knurds must be starting school soon (if they are old enough–I can’t remember!)!

      I think you’re right on the money re: the “modern scientific justification of why the romans and medieval folk drank wine as opposed to water”. It was more than just a party drug, it was a life saver!

      I was actually thinking about this very thing when writing this post. It actually reminded me of this documentary on NetFlix about beer and how it is basically the greatest creation in history. I think we can say the same for wine in many of the example they gave for beer in that documentary. It’s pretty funny and purposefully cheesy as well, and I would recommend watching it if you have NetFlix :) “How Beer Saved the World”: http://www.imdb.com/title/tt1832368/

What do you think about this topic?