Is glucose uptake dependent on insulin?

Is glucose uptake dependent on insulin?

In the human body, glucose uptake is accomplished via two mechanisms, insulin mediated glucose uptake (IMGU), which occurs only in insulin-sensitive tissues (i.e. liver, muscle and adipocytes) and non-insulin mediated glucose uptake (NIMGU), which occurs in both insulin-sensitive and non-insulin-sensitive tissues (i.e. …

Can cells uptake glucose without insulin?

Insulin Is not Required for Glucose Uptake Into Cells.

Which cells have glucose transport which functions independently of insulin?

1. Glucose transport into muscle cell is mediated by two glucose transport proteins: insulin-independent GLUT1 and insulin-dependent GLUT4. If glucose is transported though the GLUT1 pathway, it is further metabolized by hexokinase I via glucose 6-phosphate (G-6-P) and fructose 6-phosphate (F-6-P) also to hexosamines.

How does insulin control glucose uptake?

Insulin increases glucose uptake mainly by enriching the concentration of Glut4 proteins at the plasma membrane, rather than by increasing the intrinsic activity of the transporter (2,3).

What does it mean to be insulin independent?

Insulin independence was defined by fasting blood glucose levels ≤126 mg/dL and 2-hour postprandial levels ≤180 mg/dL without exogenous insulin.

Is GLUT4 insulin-dependent?

GLUT4 is an insulin-regulated glucose transporter that is responsible for insulin-regulated glucose uptake into fat and muscle cells. In the absence of insulin, GLUT4 is mainly found in intracellular vesicles referred to as GLUT4 storage vesicles (GSVs).

What happens to the glucose transporter without insulin?

In the absence of insulin, GLUT4 slowly recycles between the plasma membrane and vesicular compartments within the cell, where most of the GLUT4 resides. Insulin stimulates the translocation of a pool of GLUT4 to the plasma membrane, through a process of targeted exocytosis.

What causes glucose uptake?

Glucose uptake in response to insulin in skeletal muscle and adipose tissue is mediated by the glucose transporter GLUT4 [1,2,3,4]. GLUT4 is a 12-transmembrane protein that permits peripheral blood glucose to move into the cell across the plasma membrane.

Where does insulin promote glucose uptake?

Additionally, insulin promotes the uptake of circulating glucose into its target tissues, such as skeletal muscle and fat tissue, and thereby reduces the blood glucose level.

Which organ depends on insulin for glucose uptake?

Insulin stimulates the liver to store glucose in the form of glycogen. A large fraction of glucose absorbed from the small intestine is immediately taken up by hepatocytes, which convert it into the storage polymer glycogen. Insulin has several effects in liver which stimulate glycogen synthesis.

What causes insulin independent diabetes?

Glucose intolerance in patients with insulin-independent diabetes mellitus can theoretically arise from a loss of normal tissue sensitivity to insulin (insulin resistance) and/or from a decrease in insulin secretory capacity.

Which diabetes is insulin independent?

Type 2 diabetes mellitus is also called non-insulin dependent diabetes mellitus (NIDDM), since it can be treated with lifestyle changes and/or types of medication other than insulin therapy. Type 2 diabetes is significantly more common than type 1 diabetes.

Is GLUT2 insulin dependent?

It is the principal transporter for transfer of glucose between liver and blood Unlike GLUT4, it does not rely on insulin for facilitated diffusion.

What is meant by glucose uptake?

Abstract. Skeletal muscle extracts glucose from the blood to maintain demand for carbohydrates as an energy source during exercise. Such uptake involves complex molecular signalling processes that are distinct from those activated by insulin.

Is the kidney insulin independent?

The kidney is a known target of insulin; however, whether the kidney develops “insulin resistance” is debatable. Regulation of the insulin receptor (IR) expression and its function is very well studied in major metabolic tissues like liver, skeletal muscles, and adipose tissue.

Which hormone is most important for glucose uptake?

insulin
The pancreas produces a hormone called insulin, a chemical messenger essential for the entry of glucose into cells. As the blood glucose levels rise after a meal, insulin is released into the bloodstream and sets processes in motion to trigger the removal of glucose from the blood to enter into the cells.

What is insulin independence?