Friday 6 September 2013

Hyperinsulinemia increases GLUT4 in white adipose tissue

Hyperinsulinemia increases the amount of GLUT4 mRNA in white adipose tissue and decreases that of muscles: a clue for increased fat depot and insulin resistance.

To mimick a state of hyperinsulinemia, normal rats were infused with insulin for 4 days via minipumps, and compared to saline infused rats. At the end of the experimental period, the abundance of mRNA was increased in white adipose tissue (WAT) and decreased in muscles of "insulinized" rats compared to controls. These findings were accompanied, in all tissues considered, except the diaphragm, by parallel changes in the amount of the glucose transporter protein and by parallel changes in the in vivo glucose utilization index. Hyperinsulinemia is thus a driving force in stimulating adipose tissue metabolic activity, while bringing about incipient muscle insulin resistance.

 Anyone got full text of this? I havent seen this study on the likes of carbsanity. But anyway its quite clear as I have said before, high fasting insulin is a nasty problem and it contributes to making you fat. The calories go where the GLUT4's are. Calories into muscle = lean and strong, calories into fat = obese and lazy.

Hyperinsulinaemia increases insulin action in vivo in white adipose tissue but not in muscles.

The effect of 4 days of stable hyperglycaemia and resulting hyperinsulinaemia on insulin-induced glucose utilization by individual rat tissues was studied in vivo. The treatment produced a net increase in the glucose utilization index under both basal and insulin-stimulated (euglycaemic/hyperinsulinaemic clamp) conditions in white adipose tissue. On the contrary, glucose utilization was unchanged in aerobic muscles but was decreased in glycolytic skeletal muscles during the clamp.

Old news but still noteworthy.












5 comments:

  1. I can't get the full text unfortunately as the paper is quite old.

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  2. Interesting. I'm a fatty. A weight reduced fatty (went from 310 to 250 lbs through a combination of low carb and some resistance training), but still a fatty. I find the best way to shut down non-terminating hunger and increase energy for the rest of the day is to engage in a quick session of intense resistance training. It's like it almost instantaneously changes my phenotype from that of an obese person to one of a lean person. The thought of food is disgusting after intense resistance training. It is only after intense resistance training that I know what it feels like to be a skinny food adverse ectomorph (i.e. a hardgainer). Eventually Glut 4s on the surface of my skeletal muscle tissue downregulate and my phenotype reverts back to that of an obese person. I've been thinking of engaging in resistance training every single day for this reason. It might not be ideal for recovery, but it might be a great idea if I want to drop the rest of my excess weight, leptin levels be damned.

    Given my history of extreme insulin resistance while still having a completely normal fasting glucose, I suspect that even low carb by itself isn't enough to overcome a huge beta cell mass that pumps out a metric ton of insulin in response to even normal amounts of protein and low amounts of dietary CHO. I could try what Jimmy Moore is doing and eat an 85% fat diet, but I'd rather not end up looking like Jimmy Moore.

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    Replies
    1. interesting comment, btw I think you can resistance train every day, just dont do the same muscle groups all the time.

      and yes as so many of us have learned, lowcarb doesnt "cure" anything, it only treats the problem. like bordering up a broken window, you dont see the damage, but the window is still broken.

      no-one should have to eat a 85%fat diet just to be normal or healthy. I mean the vast majority of people are not eating a diet anything like this and are in good health.

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  3. "Calories into muscle = lean and strong, calories into fat = obese and lazy."
    +1

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  4. Nice blog. Do you have hyperinsulinism?
    Did you every try DPP4?

    Best,
    Joe

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