Exercise and Caffeine May Activate Metabolic Genes

ananyo writes "A trip to the gym could mean not just losing pounds — but also chemical modifications from DNA in the form of methyl groups. The presence (or absence) of methyl groups at certain positions on DNA can affect gene expression. Researchers at the Karolinska Institute in Stockholm looked at the methylation status of genes in small biopsies taken from the thigh muscles of healthy young adults before and after a stint on an exercise bike. They found that, for some genes involved in energy metabolism, the workout demethylated the promoter regions (stretches of DNA that facilitate the transcription of particular genes). Genes unrelated to metabolism remained methylated. Furthermore, similar demethylation could be seen when cultured muscle cells were given a massive (probably lethal) dose of caffeine."

Re:Exercising easier? Really?

[babblefrog]

A 20 oz Mountain Dew contains approximately 19 tsp of sugar. Calibrate accordingly.

Re:Translation?

[biodata]

I think it may be the other way round, if I have it right - methylation of the promoter region stops the gene being activated. The promoter is the DNA 'upstream' of the gene, usually, where the trasnscription machinery binds to begin reading off the gene and producing messenger RNA. If the promoter is methylated, the DNA doesn't unwind to provide access to the machinery. The researchers found that 'useful' metabolic genes were demethylated (so activated) by exercise and caffeine.

Re:Translation?

[Anonymous Coward]

Being methylated activates the gene. It depends on the context if it is good or bad. For example, a growth gene might be good during development, but might be bad in the case of cancer.

IAAB, and you have this backwards. Methylation is associated with gene silencing, and demethylation with activation. The extra methyl groups may in many cases inhibit the binding of transcription factors, which tend to favor canonical, unmodified DNA. This is also mentioned in TFA.

Of course, in biology, nothing is certain, and I'd bet that someone's found a transcription factor somewhere that binds to methylated DNA and preferentially activates genes in methylated regions, but the general trend is that demethylation promotes activation.

Re:Exercising easier? Really?

[Anonymous Coward]

Keep in mind that it's 60% fructose, which is broken down by the liver and at a fixed rate.

Having 50 bottles of sugar soda simply will cause your liver to be damaged in much the same way drinking a large amount of alcohol would (over the long term).

Of course, you would go into insulin shock long before that... And die from caffeine overdose and stomach rupture and about 100 other problems with this discussion.

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[account_deleted]

Comment removed based on user account deletion

Samantha Wright (nt)

[Anonymous Coward]

Filler

Re:Translation?

[Randle_Revar]

Correct, methylation stops gene expression. Mod Parent up, grandparent down

http://www.sciencedaily.com/releases/2007/04/070421211622.htm [sciencedaily.com]

Better explanation in New Scientist

[QuincyDurant]

http://www.newscientist.com/article/dn21544-exercise-instantly-boosts-fatbusting-genes.html?DCMP=OTC-rss&nsref=health [newscientist.com]

Now there is no excuse to avoid the gym: just one hour of exercise instantly changes your genes to boost the breakdown of fat.

Juleen Zierath and Romain Barrès at the Karolinska Institute in Stockholm, Sweden, and colleagues looked for epigenetic changes – the addition of a methyl group to genes – in muscle cells during strenuous exercise. To do so, the team collected biopsies from the thigh muscles of eight men who led relatively sedentary lives, both before and after an hour of exercise.

Several genes involved in fat metabolism that were methylated before the exercise lost their methyl group. Such demethylation allows genes to more easily make proteins, which suggests that more proteins involved in the breakdown of fat are being made after exercise, says Zierath.

The group was surprised to see these effects happen so quickly. They think calcium, produced in muscle cells during exercise, may be involved since subjecting the same biopsies to caffeine – which also increases calcium in muscles – caused the same demethylation.

Unfortunately, you would get caffeine intoxication before gaining the same effects from coffee as an hour-long workout, says Zierath.

Not exactly plain, nose-picker English, but I sorta get it: exercise is good for you.

Re:Exercising easier? Really?

[Auroch]

If your goal is "weight loss" then eating less is far easier and more effective than trying to burn it off at the gym. Going to the gym often makes you eat more when you get home - making it a waste of time.

(Yeah, I know it's heresy in the USA to say gym isn't the answer to everything...)

... Wrong. Eating less will only work for a while, and only if it is a moderate decrease. You burn most of your calories due to metabolic rates, and the best way to increase your metabolism is to build muscle. So no, you don't have to go to the gym. And cardio won't really do it for you either. But you do need to bulk up on your muscle mass.

Example - an hour of cardio will let you burn about 300-400 calories. Increasing your base metabolic rate by 10% will let you burn the exact same amount with absolutely NO cardio. So if you drop about 5-10% of your body fat and turn that into muscle, you'll lose the equivalent of an hour of cardio (a DAY), simply by going to the gym 3x a week and doing weights. It'll probably take you about 2 months @ 3x half an hour (so 1.5 hours a week over 8 weeks) a week to see that muscle increase, but you'll be getting the equivalent of a 7 hours a week of cardio for weight loss.

Or you could continue to believe whatever pseudoscience you're spouting (and probably read in "mens health" or equivalent trash magazine) and stay fat.