Displacement of bilirubin from albumin by berberine

A study was made of the effect of berberine, the major ingredient of the Chinese herb huanglian (coptis chinensis) reported to pose some risk for kernicterus among jaundiced newborn Chinese infants, on the protein binding of bilirubin, using the peroxidase kinetic method. Berberine was found in vitro, as to its displacing effect on a molar basis, to be about tenfold superior to phenylbutazone, a known potent displacer of bilirubin, and about hundredfold to papaverine, a berberine-type alkaloid. The chronic intraperitoneal administration of berberine (10 and 20 micrograms/g) daily for 1 week to adult rats (mixed breed of Wistar and Sprague-Dawley) resulted in a significant decrease in mean bilirubin serum protein binding, due to an in vivo displacement effect and a persistent elevation in steady-state serum concentrations of unbound and total bilirubin, possibly due to inhibition of metabolism. The use of the herb and other traditional Chinese medicines containing a high proportion of berberine is best avoided in jaundiced neonates and pregnant women.