Teenagers and Early Mornings

This Morning, BBC5live were running a science story about why teenagers were biologically idle... OK, they didn't phrase it like that they said: Melatonin levels changed at different times of the day for teenagers and that is why they struggle to get up in the morning.

OK a word on this: All animals have a "circadian rhythm" this is a daily series of hormone level changes which occurs roughly on a 24hr cycle.  First thing in the morning, just before you USUALLY get up, there is a spike in cortisol (hydocortisone) and various other changes which make getting up easier (allegedly!).  This circadian rhythm is so robust that even if you chop certain nerve cells out of the brain all together and put them into a dish and keep the dish in darkness... they still change their pattern of activity on a more-or-less 24hr cycle for a while.

No wonder, when we travel transatlantic we feel dreadful jet-lag?  We are getting the hormonal wake up and go to sleep signals still, but they are all at the wrong times.  Over a few days, the "clock" gets re-set and we can return to normal (just in time to travel back transatlantically!).  So what causes the body clock to re-adjust and eventually sort out the jet lag?  Two things: (1) Your habits, if you keep going to bed the same time, the hormones pick-up this and go with it (2) Day light.  Daylight hits particular cells of the eye and transmits a trigger signal to an area inside the brain called the hypothalamus and to the pineal gland.  Each time those day light signal hit the hypothalamus, they bring the circadian rhythm slightly back into line until eventually they you are back in sync.

So, teenagers?  Well it stands to reason that if you make a habit of getting up late, and spending longer in doors with the curtains pulled the body clock cannot adjust correctly.  I hope to read the actual paper to which the BBC were referring and see if there really is anymore to it than that.  I hope this is not a peice of "stating-the-bleedin' obvious" type of research!! 

Antibiotic Resistance

Yes, it's true. There is a danger of widespread catastrophic failure of antibiotics in the future, as stated on our radios this morning by Sally Davies. I think it is sometime off however, but here's what antibiotic resistance is all about, why it happens and what can be done to prevent it.

What does antibiotic resistance mean?

There is a feeling that "natural" things are good and "synthetic" things bad. This is why the processed food story is so appealing. Sorry, but this is simply not true. Bugs ("pathogens", bacteria, virus and fungal infections) are all totally natural and they are out to get us. Also, many natural plant extracts and animal "secretions" are poisonous without any known medicinal use. Antibiotics on the other hand are our allies. They generally derive from a natural substance, but they are then chemically synthesised in a lab. They attack bacteria in one or more of a range of possible different ways. Some attack the bacterium's cell wall (it's skin if you like) and others stop them reproducing etc etc. But they evolve. And they evolve really fast. Or the adapt and any rate like the Borg in StarTrek. When they adapt, they can withstand the attack by the antibiotics and you have to switch to a different antibiotic to get'em!

Why does it happen?
Well there are two levels to this question. "Biologically" what happens and "therapeutically" what happens. Biologically first. As I said above, it's like a kind of evolution. The genetics of bacteria change really fast and so the unfit bacteria perish and the strong ones survive. So "unfit" means unfit to fight that particular antibiotic. Get a dish of bacteria and they are constantly mutating subtly. Some mutations make them stronger, others make them weaker. This just happens. there is not much we can do about it. Then add your antibiotic to the dish: Most of the bacteria will be killed, but a few will survive, that's inevitable. BUT, here's the rub... the ones which survive will obviously be the ones who have a genetic mutation which makes them slightly better at resisting the antibiotic. Now take those survivors away, grow them up and hit them again with the same antibiotic: What would you expect? ...well the antibiotic will kill many of them, but now those strong survivors have multiplied and a large proportion of them will now survive. Take these survivors, do the same again and you have a superbug! Congratulations! ...you've moved closer to the end of mankind :-/
So medically/therapeutically how does it happen: You don't use a dish you use a person. You give a person with an infection an antibiotic and enough will be killed to make the person feel better..... but there may be a few bacterial survivors. These spread on to the next person and the experiment above is recreated in a real person rather than a dish and you are creating superbugs. Simple as that.

What can be done about it?
Well sure, invent new classes of antibiotics which work in entirely different ways to the current ones. Thanks Sally! But that is the hard way. The easier ways are these:
(1) Don't ask for antibiotics unless you really need them! (Clinicians should not give them to you even if you ask unless it really is necessary). There are frequently alternatives. Usually infections passes. If its a cold or flu antibiotics won't work anyway, because they are viral. Antibiotics only work on bacteria. You always think they work, because by the time you get the clinician to give you the drug you are just starting to get better anyway (yes even though you don't feel any better yet).
(2) Don't give them to animals to increase farming yield. Use better animal husbandry instead. If you cram your chicken (for example) into ridiculously tight spaces so infections spread by wildfire and then load them up with antibiotics "just in case".... you are not just being cruel to the chicken you are going to end up killing people. Yes you are!!!
(3) Finish your course of antibiotics if you do get them. People frequently get a course of antibiotics and stop taking them when they feel better. Its innocent enough, but this is a huge problem, It massively increases the chances of strong bugs surviving and going on to spawn a new generation of superbugs. If you read down this far and want one message its this, please please please, a thousand times please finish your meds!!!!

 

Diets of Processed Food Shorten Life Expectancy?

Last night, I sat in a restaurant toying with the idea of just ordering (for a change) a simple beefburger.  I thought of the processed food story and decided I couldn't give a duck about that... then I looked straight at the "BEEF" word and thought... I bet it isn't.  It's pony isn't it :-(

I worry about the ethics of eating old beat up equines!

...But what about the processed food story?  Would I die if I ate a beefburger... like, more than if I chose a steak?  Well the media have decided you will.  The story is everywhere!

So I read the actual paper "Meat consumption and mortality – results from the European Prospective Investigation into Cancer and Nutrition".  What does it show? Well its got masses of fancy statistics in it, but basically there is a simple correlation between the amount of process food you eat and your life expectancy... but the bad way around as the title of this blog implies!   ...but it is just a correlation! [i.e., it definitely does not mean that the processed food caused the deaths].  That means that if the people that eat lots of processed food are more likely to do other unhealthy things (like NOT eating vegetables) that other thing could be the cause of the premature death.  On page 23 of the initial PDF release of their paper/article they confess that they could not exclude the possibility that the people who eat more processed meat are more likely to smoke... and thus the real reason there appears to be an early death could be due to smoking.  So the whole thing is pretty much a waste of time.  I daresay processed food is not terribly healthy, but there are other key things that would probably make more difference.  The balance of the diet, i.e., do you eat veggies too! ....the fat content, high fat usually precipitates heart disease.  Drinking too much and smoking of course.

Gosh, why can't we get the same publicity to real science :-(

Drugs to Treat Ageing

10th March 2013

A nice review of the state of drug development to halt ageing right in its tracks just published:

"Longevity and aging- F1000Prime Biology Reports - F1000"
F1000Prime Rep2013, 5:5 (doi: 10.12703/P5-5), Published: 04 Mar 2013.
.... I could write quite a long article of this basically repeating what they say, but the bottom line is that there are a number of drugs being investigated that may extend life. The two most famous of these are rapamycin (sounds like he should be a singer? Is actually an inhibitor of the cell housekeeping enzyme called mTOR) and resveratrol (a drug found naturally in red wine... In addition to alcohol and a few other things). Both of these seem to potentially work like a calorie restricted diet to prolong life. Had you not heard that a calorie restricted diet was supposed to prolong life? No? Well many scientists believe that it does, however, naturally there are a bunch of experiments that contest this theory.
So the bottom line? The evidence seems to be strongest for rapamycin, but it is not yet proven. Benefits of the red wine chemical/ drug resveratrol is also debated, but if anything it seems to help best with people that have a high fat diet?
So watch this space. I will post updates as they become available. Rest assured scientist are on the case, and by the time we are all dead I dare say someone will have invented the secret of eternal youth. That will be a nightmare. Just think of the consequences!!!!!!




1st september 2013: Additional note, an interesting new paper by Boccardi et al., also suggest that statins may be more generalised treatments for ageing than previously thought...

Aging, Ageing, #AgeingResearch, #AgingResearch

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