Curcumin glucuronides: assessing the proliferative activity against human cell lines.
Level 5 - mechanism / opinion, no new human data
In vitro bench research using human cancer cell lines
PubMed 24280069 · doi:10.1016/j.bmc.2013.11.006
What was done
Researchers synthesized curcumin glucuronide metabolites (curcumin mono-glucuronide 2 and di-glucuronide 3) on a gram scale in four steps. They evaluated the anti-proliferative effects of parent curcumin and both glucuronide metabolites in vitro across four human cancer cell lines: KBM-5, Jurkat, U266, and A549.
What was found
Parent curcumin showed anti-proliferative activity starting at 1 μM and achieved almost 100% cell kill at 10 μM on two of the four cell lines. Curcumin mono-glucuronide and di-glucuronide showed no suppression of cell proliferation.
Why it matters
Because curcumin is rapidly metabolized into glucuronide conjugates in humans, these results suggest that glucuronidation eliminates curcumin's direct anti-proliferative activity against tumor cells.
Limits
This study was conducted entirely in vitro on cell lines without evaluating in vivo pharmacodynamics, tissue distribution, or potential intracellular deconjugation. Specific quantitative response values for the other two cell lines were not detailed in the abstract.
Cited by
- supports Glucuronidated curcumin is completely biologically inactive.