Insulin and form fibrillar interdigitated beta-sheets. This can cause injection amyloidosis, and prevents the storage of insulin for long periods. Insulin is produced in the pancreas and the Brockmann body (in some fish), and released when any of several stimuli are detected. These stimuli include ingested protein and glucose in the blood produced from digested food. Carbohydrates can be polymers of simple sugars or the simple sugars themselves. If the carbohydrates include glucose, then that glucose will be absorbed into the bloodstream and blood glucose level will begin to rise. In target cells, insulin initiates a signal transduction, which has the
Insulin resistance (generally caused by insulin resistance), this down-regulation acts as a kind of positive feedback, increasing the need for insulin. Exercise reverses this process in muscle tissue, but if it is left unchecked, it may contribute to insulin resistance. Elevated blood levels of glucose—regardless of cause—lead to increased glycation of proteins with changes, only a few of which are understood in any detail, in protein function throughout the body. Insulin resistance often is found in people with visceral adiposity (i.e., a high degree of fatty tissue within the abdomen—as distinct from subcutaneous adiposity or fat between the skin and the muscle