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Thursday 21st June 2012

The summer solstice is a significant event for quite a lot of people. I suppose for early humans the increasing length of the days must have been a cause for concern until it was realised that this was a cyclic process and that the earth was not going to end up constantly bathed in light. It is not surprise that a great deal of myth surrounds the event and many of those myths have a plant dimension, like believing a plant is at its strongest on the longest day.

But for me, this year, the significance of the summer solstice is that I’ve been able to look out at the truly awful weather for longer than on any other day.

It is no surprise that this weather has meant the garden is not looking as it should. The annuals I planted out in late May have made little or no progress and I doubt if I’m going to get any of my Nicotiana sylvestris, woodland tobacco, to flower. Here’s something I don’t understand. Many people have told me about using tobacco soaked in water to make a good insecticide for the garden. There was a time when such insecticides were available commercially but they are now outlawed and home-brewing is also discouraged.

So, how is it that something is munching its way through the leaves of my young Nicotiana plants with apparent impunity?

The only thing that is doing well in spite of the weather is the Digitalis, foxgloves. And that’s handy because, if the Daily Mail is to be believed¹, that’s a plant for which demand may be about to increase.

Of course, the Daily Mail is not to be believed. Like most of the media it has taken the publication of some very early research giving an indication of an avenue for further work likely to take many years and presented it as a firm conclusion with immediate impact.

Researchers have known, for about ten years that a protein labelled RGS2 is important in cardiovascular health. The work seized on by the Mail involved researchers testing thousands of chemicals to see if any of them had an effect on the protein.² They discovered that digoxin, from the foxglove, was one of several compounds that seemed have an effect on RGS2 levels.

They did some further work on cells in the lab to confirm this and conclude that this could be an interesting avenue for further study. At some point, a fair way in the future, digoxin might offer a means of treating high blood pressure. The always excellent NHS Choices website reports on the research and the media coverage in more detail.³

For the Mail to say in its headline ‘Foxglove can protect against high blood pressure’ is like saying the summer solstice means continuous bright sunshine for over fifteen hours. It is completely irresponsible to give people false hope that a resolution to their long-running health problem may be just around the corner, especially considering that digoxin carries a high risk from even a small overdose so it is unlikely that it could ever be very widely used to control blood pressure.

Sorry if that is a bit of an ill-tempered rant. It's been a long day.

References

^1.How extract from poisonous Foxglove can PROTECT against high blood pressure and heart failure Mail Online 15th June 2012  
^2.Cardiotonic steroids stabilize RGS2 protein levels Molecular Pharmacology Fast Forward. Published on June 13, 2012 as doi:10.1124/mol.112.079293
^3.'Foxglove extract digoxin helps the heart' NHS Choices Behind the Headlines 18th June 2012

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