Blood cholesterol levels (TC)

Blood cholesterol levels represent a clinical measurement of the concentration of sterols, primarily low-density lipoprotein (LDL) and high-density lipoprotein (HDL), circulating in the bloodstream. While cholesterol is an essential structural component of cell membranes and a precursor for steroid hormones and bile acids, chronically elevated levels of LDL cholesterol are a major driver of atherosclerosis. This condition involves the accumulation of plaque in arterial walls, leading to increased risk of myocardial infarction, stroke, and peripheral vascular disease. Although 'blood cholesterol levels' is a physiological state or biomarker rather than a single molecular target like an enzyme or receptor, it is the primary therapeutic endpoint for lipid-lowering drugs. Pharmacological interventions generally target specific proteins such as HMG-CoA reductase, PCSK9, or NPC1L1 to decrease the production, increase the clearance, or decrease the absorption of cholesterol, respectively. Management of these levels is a cornerstone of cardiovascular risk reduction in clinical practice.

Other names

Serum cholesterolPlasma cholesterolTotal cholesterolLipid profileCholesterolemia

Drugs modulate blood cholesterol levels by targeting specific proteins involved in its metabolism: statins inhibit HMG-CoA reductase to reduce endogenous cholesterol synthesis; PCSK9 inhibitors prevent the degradation of Low-Density Lipoprotein Receptors (LDLR), enhancing the clearance of LDL from the blood; ezetimibe inhibits the NPC1L1 transporter to block intestinal cholesterol absorption (StatPearls, 2023) [https://www.ncbi.nlm.nih.gov/books/NBK459188/].