In every mammal, Glucose is acts as an important energy source metabolic substrate. It is obtained directly from the diet, principally following the hydrolysis of ingested disaccharides and polysaccharides, and by synthesis from other substrates in organs such as the liver. In the breakdown of each gram of carbohydrates, four calories of energy are consumed. Once ingested into the body, special enzymes in the digestive system break down the carbohydrates into simple sugars called glucose. This breaking down process allows the body to access the calories of energy contained in the carbohydrate. Glucose derived from the diet is transferred from the lumen of the small intestine, and both dietary glucose and glucose synthesized within the body have to be transported from the circulation into target cells.
Normally a healthy individuals completed their daily works by the help of energy which is actually derived from the breakdown of simple sugars. Glucose – C6H12O6 – a simple sugar that is influential in providing energy for cells in our body. In fact, it’s the main power supply for most cells, and is the only energy supply for certain cells like brain cells and red blood cells because, under normal conditions, glucose is the sole substrate for these tissues. In our body glucose is mostly utilized by the brain, neurons and developing red blood cells for achieving energy. In all these tissues, after the glucose metabolism the main outcome is to yield energy in the form of adenosine triphosphate (ATP).
There are two methods by which glucose is produced endogenously to maintain plasma glucose levels: glycogenolysis and gluconeogenesis
Gluconeogenesis (GNG) is a metabolic pathway that results in the synthesis of glucose from non-carbohydrate precursors, such as pyruvate, lactate, glycerol, and glucogenic amino acids.
According to the David, Nelson and Michael, plants, animals, fungi, bacteria, and other microorganisms plays a pivotal roles for spontaneous generation of glucose by gluconeogenesis(1). However, some precursors for biosynthetic reactions, such as the formation of some amino acids, nucleotides and other intermediary metabolites has been produced after the metabolism of glucose. If unfortunately our carbohydrate level will goes down from the normal levels, then our normal body homeostasis make it balanced by depletion of glycogen stores to give the brain fuel. Once the stores fail, the body begins to break down muscle tissue to make glucose.
In 1977, Young told that Gluconeogenesis took place mainly in the liver for vertebrates, and, to a lesser extent, in the cortex of the kidneys (2). During periods of fasting, starvation, low-carbohydrate diets, or intense exercise this process occurs rapidly in many other animals (3).Usually the liver and the kidneys are the two major sites for gluconeogenesis, but the 90% of the gluconeogenesis is happened in the liver & the rest of the glucose production is carried out by the kidney in healthy individuals. But very small amount of glucose production is happened by other tissues. For maintain the metabolic demand of glucose on the brain, muscle & red blood cells, the liver and …
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