PHARMACEUTICALS
Bile acids :
From ancient Chinese medicines to modern treatments
Dr Alex Weymouth-Wilson of ICE Group looks at how bile acids are emerging as a therapy in multiple fields
Figure 1 – Bile acids
CA CDCA DCA LCA UDCA Meanwhile in Japan 1953 Tanabe Seiyaku Co . Ltd developed UDCA as a liver tonic , inspired by the
Bile from a wide variety of animals has been used in Chinese medicines to treat various diseases and ailments from as early as the Zhu dynasty over three millennia ago . Modern research is now highlighting the potential of bile acid and bile salts for various therapeutic areas . Bile acids are synthesised from cholesterol in the liver . The primary bile acids in humans are cholic acid ( CA ) and chenodeoxycholic acid ( CDCA ). These are converted to secondary bile acids in the gut by microbial actions : deoxycholic acid ( DCA ) is produced from CA , lithocholic acid ( LCA ) from CDCA ( Figure 1 ). It is well known that bile acids play an essential nutritional role in the solubilisation and absorption of dietary fat and lipid-soluble vitamins , as they are natural detergents . In addition , due to the detergent nature of bile acids and bile salts , they are part of the mechanism to control bacterial overgrowth in the gut by disrupting and fragmenting the cell walls of the bacteria . Despite the elucidation and understanding of the true chemical structures of bile acids in the early part of the 20th century , there was little interest in them in Western medicine . Western medical professionals at the time thought that they had few therapeutic properties .
Modern interest begins
Meanwhile in Japan in 1953 , Tanabe Seiyaku developed UDCA as a liver tonic , inspired by the claimed therapeutic effects of bear bile . This was a low 10mg dose and was taken to promote digestion and assist with indigestion . The Chinese had always considered bear bile or xiong dan , in which the major bile acid is UDCA , to be the ‘ king ’ of animal biles and it was used widely throughout ancient China to treat conditions from jaundice to laryngitis . In the early 1970s , CDCA was shown to decrease biliary cholesterol saturation and Dr Falk Pharma marketed it for the dissolution of radiolucent gallstones , establishing the first Western bile acid medicine . UDCA soon superseded CDCA in this application , because it was proven to be a safer product with no hepatoxicity effects . It was not until the early 1990s that UDCA found another therapeutic application , in the prevention or delay of liver damage in patients with primary biliary cholangitis ( PBC ). PBC is characterised by an inflammatory lesion of the interlobular bile ducts , which results in the destruction of the bile duct ‣
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