Normal blood sugar is tightly regulated glucose production in the liver, glucose uptake and utilization by peripheral tissues, mainly skeletal muscles, and the actions of insulin and glucagon.

Catabolism is the major source of energy for cellular processes.

Glucose is taken up differently for various tissues dependent on glucose transporters.

Glucose is a polar compounds thats solubility and transportability occurs through specialized tissue glucose transporters, particularly in the kidney tubule, the small intestine, the brain, and peripheral tissues.

Two gene families are involved in glucose transport and include the sodium-glucose cotransporters (SGLT’s) and facilitated glucose transporters (GLUT’s).

Glucose transporters facilitate passive transport along membranes and sugar-glucose cotransporters are involved in active transport.

Glucose is an osmotic molecule, and can have effects on osmotic pressure in high concentrations possibly leading to cell damage or death if stored in the cell without being modified.

SGLT2 is the most important renal transporter and reabsorbs nearly 90% of the glucose that is filtered by the glomeruli, and is minimally expressed elsewhere, while SGLT1 absorbs the remainder.

Glucose uptake in muscle and fat is insulin level dependent.

Glucose use in the brain is primarily insulin independent.

The brain accounts for approximately 60% of the total basal glucose consumption, and because of it’s limited glycogen reserves the symptoms of hypoglycemia are primarily neurologic in origin.

Insulin and glucagon have opposing regulatory effects on glucose homeostasis.

The kidney plays a major role in glucose homeostasis by gluconeogenesis and glomerular filtration absorption of glucose in the proximal convoluted tubules.

The glomeruli of the normal adult kidney filters 180 g of glucose daily.

Glucose reabsorption from the tubules is virtually complete with less than 1% being excreted in the urine.

The reabsorption of glucose from kidney tubules is a multistep process and once filtered into the tubule must be transported through the tubular epithelial cells and then across the basolateral membrane into tubular capillaries.

When tubular glucose load is approximately 120 mg/minute or less, no glucose is lost in the urine.

When tubular glucose load exceeds 220 mg/minute, the glucose threshold, glucose begins to appear in the urine.

The tubular glucose threshold ranges between 130 and 300 mg per deciliter, and the threshold increases with age.

Glycosuria generally does not occur until the blood glucose concentration exceeds 180 mg per deciliter.

Pure dietary glucose is found in a modified corn syrup has relatively little sweetness.

Following dietary glucose stimulates insulin secretion, promotes glycogen synthesis in the liver and glucose uptake by tissues throughout the body.

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