What is Microscopic infiltrate, MST or myostatin toxin therapy? Myostatin is a naturally occurring protein found in cattle's muscle and bones. The protein is secreted from the muscle. Over time myostatin builds up inside the muscle cells destroying the myostatin. This protein is being used as a natural way to prevent muscle loss in people with MOSTLY insulin resistance situations, where the pancreas has NOT produced sufficient amounts of insulin. The problem with injecting insulin is that it stops the pancreas from producing the protein on its own. This stops the muscle cell from absorbing glucose. So, the only way to get the glucose into the muscles is by micro-injecting myostatin protein into the muscle. ( Note: Myostatin does NOT stop the heart beat, it only acts as an insulin suppressor.) Micro-injection therapy works best with someone who is insulin resistant. This means the person must have had their blood work done, and need to be on a long term maintenance drug. Also some p