Carbohydrate metabolism is a fundamental biochemical process that ensures a constant supply of energy to living cells. The most important carbohydrate is glucose, which can be broken down via glycolysis to enter into the Krebs cycle and eventually lead to the production of ATP through oxidative phosphorylation.
Glucose transport into cells is facilitated by a family of transport proteins called GLUT (Glucose Transporters). GLUT4 is the primary glucose transporter for insulin-stimulated glucose...

Management of atherosclerosis involves an integrated strategy encompassing pharmacological treatment, surgical interventions, lifestyle changes, and nutrition therapy to address the multifactorial nature of the disease.Pharmacological TherapyA cornerstone of atherosclerosis management is the use of pharmacological agents. Statins, such as atorvastatin, are pivotal in inhibiting HMG-CoA reductase, an enzyme that catalyzes an initial step in cholesterol synthesis in the liver. This reduction in...

Without prolonged fasting, healthy individuals maintain blood glucose levels above 3.5 mM due to a well-adapted neuroendocrine counterregulatory system that effectively prevents acute hypoglycemia, a potentially life-threatening condition. The primary clinical scenarios for hypoglycemia encompass diabetes treatment, inappropriate production of endogenous insulin or insulin-like substances by tumors, and the use of glucose-lowering agents in non-diabetic individuals. Notably, hypoglycemia in the...

Diabetic ketoacidosis (DKA) is a metabolic emergency characterized by hyperglycemia, ketonemia, and metabolic acidosis. It results from severe insulin deficiency and an excess of counterregulatory hormones, leading to uncontrolled lipolysis, ketogenesis, and widespread electrolyte and fluid disturbances.Pathophysiology The central event in DKA is a profound loss of insulin action. Without insulin, glucose uptake in insulin-dependent tissues is impaired, while hepatic glucose production...

During the initial hours of fasting, the body uses up its glycogen stores as an energy source. Once these glycogen reserves are depleted, the body begins breaking down stored triglycerides and structural proteins. During this stage, glycerol becomes a key substrate for gluconeogenesis, while free fatty acids undergo beta-oxidation to provide energy for tissues, such as skeletal muscle. In the fasting state, the body spares protein breakdown as much as possible to conserve muscle and structural...

The postabsorptive state usually starts about four hours after a meal and lasts until the next meal is eaten. During this time, the digestive system stops absorbing nutrients, and the body uses stored energy reserves to maintain stable blood glucose levels.
Initially, glycogen stored in the liver is broken down to release glucose into the bloodstream, while glycogen in the muscles is broken down to supply glucose for energy directly within the muscle cells. As glycogen stores diminish,...