Scientists believe they may be on to a possible cure for cocaine addiction with the help of bile acids, the gut compounds used for digestion.
When it comes to solving a major health problem such as cocaine addiction, scientists from Vanderbilt University Medical Center believe an answer could lie in our own body.
In a paper published to PLOS Biology, a research team at the university found strong evidence that bile acids – gut compounds used by the digestive system to break down dietary fats – could reduce the desire for cocaine.
Those in the team have long studied metabolic changes associated with bariatric surgery for weight loss, with patients typically experiencing dramatic changes in glucose regulation and taste preferences when in recovery.
Realising that something beyond our understanding was happening here, the researchers questioned whether elevated serum bile acids – a common effect of bariatric surgery – were affecting the reward centres of the brain for fatty foods.
In the most common type of bariatric surgery, Roux-en-Y gastric bypass, the surgeon restricts the size of the stomach and alters the path of the food through the digestive tract. This also changes where bile acids enter the small intestine, increasing the circulation of the acids in the body.
Testing this theory in mice using a procedure called bile diversion, the researchers connected the gall bladder of a mouse to its small intestine.
For obese mice, the procedure reduced their weight and desire for fatty foods; in normal-weight mice, the procedure reduced cocaine-induced increases in brain dopamine release and also reduced cocaine-associated behaviours.
Expanding on this knowledge, a synthetic bile acid drug called obeticholic acid (OCA) was given to mice without surgery.
Once again, it was shown to reduce a desire for cocaine and that the bile acid receptor TGR5 mediates the effects of elevated bile acids in the reward circuitry of the brain.
“Will bile acids cure cocaine addiction in humans? We don’t know, but our research certainly suggests that bariatric surgery or consumption of bile acids may have beneficial effects,” said Charles Flynn of the research team.
“OCA is already clinically approved, so it might be possible to move quickly to clinical trials of its efficacy in treating addiction.”