Sherlock (grazie!) sent me the full curcumin/cell membrane study (abstract: http://tinyurl.com/atknp7), the one that I mentioned in my March 9 2009 post. What was I thinking? What do I know about gramicidin channels of varying lengths and bilayer deformations? Er, not much, I’m afraid…
But…I tried. And, incredibly!, I managed to glean a few pearls. As follows.
Despite intense interest in the physiological effects of curcumin, a general mechanism for its action has not been identified. Studies of curcumin have shown that it influences structurally unrelated membrane proteins across several signaling pathways.
So the business about curcumin possibly affecting membranes had been hypothesized in previous studies. In a moment of utter madness, I actually glanced at a couple. A 2008 study (see http://tinyurl.com/buza49) suggested that curcumin affects the function of membrane proteins. But these changes had not been studied in detail until Prof. Ramamoorthy and his group examined them with solid-state nuclear magnetic resonance techniques (see: http://tinyurl.com/cvvzb3).
After trying to make heads or tails of quadrupolar coupling, acyl chains, anionic amphiphiles and all the other incomprehensible (to me) thingies mentioned in Prof. Ramamoorthy’s report, I gave up and jumped directly to the Discussion…parts of it were beyond my comprehension even after several read-throughs. But a few things were fairly clear.
An interesting suggestion concerns liposomal curcumin: It has also been reported that liposome-encapsulated curcumin has greater bioavailability and in vivo efficiency. Our results suggest that the incorporation of curcumin into liposomes strongly enhances the stability of curcumin and may have a strong impact on the demonstrated greater effectiveness of liposomal curcumin.
Curcumin stuck inside a liposome (see: http://en.wikipedia.org/wiki/Liposome)….a simple (?) solution that sounds better (to me) than the enteric-coated capsule idea.
Important excerpt: Cancer cells treated with curcumin display some features typical of apoptotic cell death […]. However, other features of curcumin-induced cytoxicity […] are not typical of standard apoptosis and point to a direct action of curcumin on the membrane as the initial step in the cytotoxic effect of curcumin on cancer cells. Fascinating.
In conclusion, this 2009 study is the first to detail the real and dramatic changes caused by curcumin in cell membranes. I found most of it difficult or even impossible to interpret, but the parts that suggest that curcumin’s anticancer activity begins at the atomic level might help explain why this yellow-orange powder keeps some of us stable in spite of its well-documented poor bioavailability. Of course, given my lack of scientific training, this is just my own guesswork!