Gallensäuren

Gallensäuren, also known as bile acids, are a group of steroid acids synthesized in the liver from cholesterol. They play a crucial role in the digestion and absorption of fats and fat-soluble vitamins in the small intestine. The primary bile acids synthesized in the liver are cholic acid and chenodeoxycholic acid. These are then conjugated with glycine or taurine, forming bile salts, which are more water-soluble.

Bile, containing these bile salts, is stored in the gallbladder and released into the duodenum in response to the consumption of a fatty meal. In the intestine, bile salts emulsify large fat globules into smaller droplets, increasing the surface area for pancreatic enzymes to act upon. They also form micelles, which are essential for the absorption of fatty acids, monoglycerides, and fat-soluble vitamins (A, D, E, and K) by the intestinal cells.

After their role in digestion, the majority of bile acids (around 95%) are reabsorbed in the ileum and returned to the liver via the enterohepatic circulation. A small amount is excreted in the feces. This efficient recycling process conserves the body's bile acid pool. Bile acids also have signaling functions, acting on various receptors to regulate lipid and glucose metabolism. Disruptions in bile acid synthesis or enterohepatic circulation can lead to various health issues, including malabsorption and liver diseases.