Resveratrol and Type 2 diabetes

The role of resveratrol in disease prevention and treatment continues to increase and clear-cut cases have been documented. A lot of studies have shown that resveratrol plays a significant role in diabetes.

Insulin Resistance
A hormone, known as insulin, produced and secreted by the beta cells of the pancreas, is responsible for driving glucose in the blood circulation into the cells, especially cells of the skeletal muscles. In the cells of the muscles, the glucose is used either for energy production or storage as fat. What this means is that after every carbohydrate meal and the glucose level in the blood begins to rise, insulin production and release also start to increase. This insulin drives the glucose above the normal blood level of insulin into the cells. When that is done and the level of glucose in the blood returns to normal, insulin secretion stops.

Now, our meals in this part of the world are a high carbohydrate and high fat diet. The carbohydrate portion of what we eat is mainly starchy foods that have high glycaemic indices. The glycaemic index of a nutrient is the rate at which such a nutrient is absorbed into the blood (or the rate at which a nutrient appears in the blood) and causes the release of insulin. These starchy nutrients with high glycaemic indices, being the main stay of our diet cause a sudden release of insulin into the circulation. I am talking of such foods as white flour and its products, polished rice, pasta, yam, potatoes etc. These types of food cause what is known as an insulin spike or surge.

This is the sudden outpouring of insulin into the circulation in response to the sudden increase of glucose. In a short time, this insulin will drive all the glucose into the cells. When this is done, the individual begins to feel hungry and reaches for a soft drink (soda) and a snack, both of which will elicit another insulin spike. This is repeated all day long for several weeks, months and years until there comes a time when the cells no longer respond appropriately to the insulin; response begins to diminish. As it happens, the level of glucose in the blood will continue to rise and force the beta cells of the pancreas to secrete more insulin to try and drive the glucose into the cells. As this goes on, the level of insulin reaches an all-time high, a condition that is known as hyperinsulinaemia. This disorder is referred to as INSULIN RESISTANCE.

Even though the high blood insulin level may effectively control the blood glucose level, this level of insulin in the blood may give rise to certain serious health challenges. The following are features of the adverse effects of elevated insulin level in the body: hypertension, low HDL (good) cholesterol, high LDL (bad) cholesterol, high triglycerides, increased incidences of blood clots, increased rate of inflammation of the arteries and development of central obesity (weight gain mainly around the lower abdomen, giving an apple appearance.

Insulin resistance is the stage before the full-blown diabetes mellitus at which the beta cells in the pancreas become exhausted and begin to fail in insulin production. As insulin level falls, blood glucose level rises.

Effect of resveratrol on the management of complications of insulin resistance/diabetes
In research studies on animals and man in a few cases, resveratrol has been found to have the following effects:

Resveratrol reduces blood sugar level. It also reduces insulin resistance by lowering the insulin level in the blood. The level of HDL (good) goes up with resveratrol, while that of LDL (bad) cholesterol is reduced. Total cholesterol and other fats such as triglycerides are reduced. The systolic blood pressure in particular that was increased goes down and the risk of coronary heart disease is further reduced. Resveratrol has also been found to inhibit clot formation in the walls of the arteries.

Resveratrol and other complications of diabetes mellitus
Diabetic retinopathy
This is due to a microangiopathy, a disease that causes damage to the micro vascular network of the blood vessels in the retina. It could also be as a result of the development of poorly formed micro vessels in the retina. These both can cause inflammation, exudates and oedema (swelling) of the retina, which can eventually lead to blindness.

Resveratrol can halt the onset and development of this diabetic retinopathy by inhibiting inflammation and preventing angiogenesis (formation of new blood vessels). It also prevents capillary leakage and exudates in the retina.