Blood sugar level In humans, glucose is the primary source of energy, and is critical for normal function, in a number of tissues, particularly the human brain which consumes approximately 60% of blood glucose in fasted, sedentary individuals. Glucose can be transported from the intestines or liver to other tissues in the body via the bloodstream. Cellular glucose uptake is primarily regulated by insulin, a hormone produced in the pancreas. Glucose levels are usually lowest in the morning, before the first meal of the day, and rise after meals for an hour or two by a few millimoles. Blood sugar levels outside the
Glucose major facilitator superfamily. In the small intestine (more precisely, in the jejunum), glucose is taken up into the intestinal epithelial cells with the help of glucose transporters via a secondary active transport mechanism called sodium ion-glucose symport via the sodium/glucose cotransporter 1. The further transfer occurs on the basolateral side of the intestinal epithelial cells via the glucose transporter GLUT2, as well as their uptake into liver cells, kidney cells, cells of the islets of Langerhans, nerve cells, astrocytes and tanyocytes. Glucose enters the liver via the vena portae and is stored there as a cellular glycogen. In the liver