Bile salt metabolism pathway

The **bile salt metabolism pathway** refers to the complex series of biochemical reactions responsible for the synthesis, conjugation, secretion, modification by gut bacteria, reabsorption (enterohepatic circulation), and signaling functions of bile acids/salts. This process begins in hepatocytes with conversion of cholesterol into primary bile acids—mainly cholic acid and chenodeoxycholic acid—via enzymes such as cholesterol 7α-hydroxylase (CYP7A1). These are then conjugated with glycine or taurine before being secreted into the intestine where they emulsify dietary fats. In the gut lumen, bacterial enzymes further modify these molecules into secondary bile acids through deconjugation and dehydroxylation steps involving specific microbial pathways like those encoded by bai genes.[1][3][6] Bile salts are efficiently recycled back to the liver via transporters including ASBT/SLC10A2 in enterocytes; this enterohepatic recirculation conserves resources while tightly regulating systemic lipid balance.[3] Beyond their digestive role, certain bile salts act as ligands for nuclear receptor FXR and GPCR TGR5—modulating gene expression related to lipid/glucose metabolism,[4] inflammation,[2] energy expenditure,[2] and even influencing cardiovascular risk.[2][4] Therapeutically relevant interventions target various points along this metabolic axis—for example using sequestrants that bind intestinal bile salts or synthetic agonists/antagonists that modulate receptor-mediated signaling.[2][4][7] Disruption at any step can have significant clinical consequences ranging from dyslipidemia to cholestatic liver disease. **Note:** "Bile salt metabolism pathway" is not a single molecular target but rather a collection of interconnected enzymatic reactions involving multiple proteins/receptors/transporters. It should not be treated as an individual therapeutic target; instead focus should be placed on specific components within this network such as CYP7A1 enzyme ("Cholesterol 7 alpha-hydroxylase"), ASBT transporter ("Apical sodium-dependent bile transporter"), or receptors like "Farnesoid X receptor" (FXR) when seeking structured data about drug targets.[1][3][6] If you require information about one specific component/protein/receptor within this pathway for structured data purposes—for example "Farnesoid X receptor"—please specify which one.

Other names

Bile acid metabolism pathwayBile acid synthesis and recyclingEnterohepatic circulation of bile acidsBile salt metabolic process

Sequestration of bile acids in the intestine to reduce cholesterol reabsorption and lower LDL cholesterol levels Activation or inhibition of nuclear receptors like FXR to regulate bile acid synthesis and metabolic effects on lipids/glucose homeostasis[4][7]