What Are Liver Function Effects on Blood Sugar?

The liver plays a vital role in regulating blood sugar levels.

The liver's role in regulating blood sugar levels in the body ensures that energy is available to carry out daily tasks and activities. A number of mechanisms are in place to respond to changing chemical conditions in the blood. Cellular and organ processes rely on the effects the liver has on blood sugar levels.

Digestion Process

The liver is an essential organ within the body's digestive process. The stomach and intestine work to grind up ingested foods and release these materials into bloodstream. From there, the liver converts available carbohydrates, fats and proteins into usable forms for the body's cell structures. One of the liver's primary roles is to maintain certain blood sugar levels within the bloodstream. This entails providing more sugar, or glucose, when levels are low, and removing excess amounts when levels are high.

Liver Function

The liver is the largest gland in the human body, weighing in at around 3 to 4 lbs. Its cells--called hepatocytes--are designed to process nutrients and filter out toxic and waste materials. Blood sugar mechanisms are regulated by a series of metabolic pathways contained within the cells of the liver. As the body's blood sugar levels must remain near 0.1 percent at all times, the liver is constantly working to monitor and regulate what materials are needed. Glucose and glycogen are the two forms that sugar takes within the body. The liver's job is to manufacture, store and release sugar in accordance with the body's needs.

Glycogenolysis

Low blood sugar conditions prompt the metabolic pathways in the liver to restore needed levels. Glycogenolysis is the process used to convert glycogen materials into glucose. Glycogen is the form sugar takes when it's being stored inside the liver. Hepatocyte cells work to break down glycogen reserves into glucose, which is then secreted into the bloodstream. The amount needed to restore blood levels is determined by existing blood sugar levels. These conditions let metabolic pathways know when the needed levels have been reached.

Gluconeogenesis

If blood sugar levels should drop at a time when the liver has no glycogen reserves available, the liver must manufacture new glucose out of amino acid materials. Gluconeogenesis is the process through which alanine--an amino acid produced by the muscles--is used to make glucose. This process is also coordinated by metabolic pathways in response to chemical conditions in the bloodstream and the liver. Under conditions of starvation, gluconeogenesis processes will utilize cell and muscle byproducts to manufacture needed glucose materials.

Glucose Cycle

The glucose cycle is the process used by the liver to convert cell byproducts back into glucose. Glucose-6-phosphate materials are byproducts from the cellular metabolism process. These materials are secreted into the bloodstream and transported to the liver. Using an enzyme called glucose-6-phosphatase, the liver is able to break down cell byproducts and convert them back into glucose. Glucose-6-phosphate is also a product of the glycogenolysis and gluconeogenesis cycles. In effect, the liver is able to utilize any one of these mechanisms to ensure blood sugar levels remain stable.

References

• Glycogen Synthesis and Metabolism
• Metabolism

Resources

• Principles of Liver Support Systems