четверг, 12 июня 2014 г.

Statins and Exercise

 

 
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Pathways for muscle damage and rhabdo.
Statins block an enzyme that occurs early in the long chain of events leading to the production of cholesterol. Many other fats and enzymes originate on that chain as well, so statins may have far-reaching effects on many elements of the body and of metabolism.

A striking aspect of statin use is pointed to by Stephanie Seneff in her essay Why Statins Don't Work. "Statins, then, slowly erode the muscle cells over time. After several years have passed, the muscles reach a point where they can no longer keep up with essentially running a marathon day in and day out. The muscles start literally falling apart, and the debris ends up in the kidney, where it can lead to the rare disorder, rhabdomyolysis, which is often fatal. In fact, 31 of our statin reviews contained references to "rhabdomyolysis" as opposed to none in the comparison set. Kidney failure, a frequent consequence of rhabdomyolysis, showed up 26 times among the statin reviews, as opposed to only four times in the control set. "

Statin-induced damage to muscle can be detected in tests for creatine kinase in the blood. Here is her elegant summary of the four complications of statin therapy for muscles: "
The skeletal muscle cells are severely affected by statin therapy. Four complications they now face are:

(1) their mitochondria are inefficient due to insufficient coenzyme Q10,

(2) their cell walls are more vulnerable to oxidation and glycation damage due to increased fructose concentrations in the blood, reduced cholesterol in their membranes, and reduced antioxidant supply,

(3) there's a reduced supply of fats as fuel because of the reduction in LDL particles, and

(4) crucial ions like sodium and potassium are leaking across their membranes, reducing their charge gradient. Furthermore, glucose entry, mediated by insulin, is constrained to take place at those lipid rafts that are concentrated in cholesterol. Because of the depleted cholesterol supply, there are fewer lipid rafts, and this interferes with glucose uptake. Glucose and fats are the main sources of energy for muscles, and both are compromised."

As a result, muscle metabolism becomes dependent on anaerobic metabolism and the production of lactate. The mitochondria can no longer keep up energy supply and the FTb fibers atrophy and the release of contents from the damaged muscle damages the nerves. No wonder so many older individuals, most of whom are likely on statin therapy lose their ability to generate force rapidly or to maintain activity for long periods.

There is a nice summary of rhabdo, its causes and its consequences (often death). http://www.medicinenet.com/rhabdomyolysis/article.htm