We got a paper published the other month. In an attempt to increase science on here, and improve my ability to talk about complicated matters I’m going to do explain it to you dumb-dumbs.*
So, muscles can spit out a bunch of stuff; these are called myokines. When you do exercise your muscle starts spitting out more things. Some of these then move throughout your body and have positive effects elsewhere. This is one of the reasons why exercise is good for you.
In Type 2 Diabetes, your muscle becomes worse. It becomes insulin resistant, and stops taking up glucose after insulin stimulation. Skeletal muscle from Type 2 diabetics is weaker, and less able to function properly. So does Type 2 Diabetes affect the muscle’s ability to spit out all that junk? Does it now spit out nasty things?
Hell yeah it does! Both times.
We took muscle from people with and without diabetes and grew muscle cells in the lab. (You know those guys who grew a burger in the lab? Ted and Bob basically invented that technique!) We found out that muscle cells from Type 2 diabetics secretes more nasty proteins, and that a lot of these nasty proteins are high in the blood of the same folks. A lot of these myokines are pro-inflammatory, which you can imagine are usually the bad guys.
We then treated the cells with some pro- and anti-inflammatory things, to see if that would effect the muscle in different ways. Muscle cells from Type 2 diabetics responded more abruptly to pro-inflammatory stimuli (palmitate and LPS) suggesting that these cells are “primed” by the disease. Another difference was seen with anti-inflammatory stimuli. Using the diabetic medicine pioglitazone diabetic muscle secretes less nasty junk, but oleate, a anti-inflammatory dietary lipid, had a diminished affect.
Take that chumps obsessed with “natural” things over medications, you bags of dummies.
So what does this all of this do? Well we looked at the effect on muscle itself. This called an “autocrine*” effect. So we looked at the two functions of muscle; glucose uptake, with and without insulin; and oxidation of fatty acids. Both of these are diminished in Type 2 Diabetic muscle. Whilst there was no real difference in glucose uptake (apart from pioglitazone increasing it all), the fatty acid oxidation was increased by palmitate and pioglitazone treatment. This is a bit strange as they have opposite effects on myokine secretion.
Now for potentially some more confusing science.
Muscle cells from Type 2 diabetics have higher levels of pro-inflammatory proteins than muscle cells from non-diabetics. When you stick pro-inflammatory stimuli on Type 2 diabetic muscle the cells are already maxed out, whereas muscle from non-diabetics suddenly have increased pro-inflammatory signalling. Conversely, anti-inflammatory stimuli have no effect on the non-diabetic cells as they are already sorted, but muscle from Type 2 diabetics responds properly and the pro-inflammatory signalling is decreased.
So, what have we learnt?
Muscle cells from Type 2 diabetics secretes a whole bunch of nasty things.
Diabetes medication may lower this secretion.
Possibly because they are maxed out on pro-inflammatory pathways.
However, the myokines may not contribute effectively to muscle function.
Today’s quote is from Haruki Murakami
* Or you know, people who don’t care about myokines.
**”auto” for self and “crine” for erm… well I think it’s taken from endocrinology and the endocrine system, basically meaning the spitting out of things, which in turn have an effect. Jeez this is going terribly.