Thursday, January 6, 2011

New Study Shows Honey, Propolis Flavonoids Protect Liver

Propolis contains numerous flavanoids and depending on its origin, their concentrations may vary. Chrysin is consistenly found European and North American Propolis and having its concentration certified is a real plus... 
Chrysin Abrogates Early Hepatocarcinogenesis and Induces Apoptosis in N-Nitrosodiethylamine-Induced Preneoplastic Nodules in Rats
Toxicology and Applied Pharmacology, Article in Press, 2011, January 04

Flavonoids possess strong anti-oxidant and cancer chemopreventive activities.

Chrysin (5,7-dihydroxyflavone) occurs naturally in many plants, honey, and propolis. In vitro, chrysin acts as a general anti-oxidant, causes cell cycle arrest and promotes cell death. However, the mechanism by which chrysin inhibits cancer cell growth and the subcellular pathways activated remains poorly understood.

Effect of dietary supplementation with chrysin on proliferation and apoptosis during diethylnitrosamine (DEN)-induced early hepatocarcinogenesis was investigated in male Wistar rats.

To induce hepatocarcinogenesis, rats were given DEN injections (i.p, 200 mg/kg) three times at 15 day interval. An oral dose of chrysin (250 mg/kg bodyweight) was given three times weekly for 3 weeks, commencing 1 week after the last dose of DEN. Changes in the mRNA expression of COX-2, NFkB p65, p53, Bcl-xL and β-arrestin-2 were assessed by quantitative real-time PCR. Changes in the protein levels were measured by western blotting.

Chrysin administration significantly (P < 0.001) reduced the number and size of nodules formed. Also, a significant (P < 0.01) reduction in serum activities of AST, ALT, ALP, LDH and γGT were noticed. Expression of COX-2 and NFkB p65 were significantly reduced whereas that of p53, Bax and caspase3 increased at the mRNA and protein levels. Likewise, a decrease in levels of β-arrestin and the anti-apoptotic marker Bcl-xL was also noted. These findings suggest that chrysin exerts global hepato-protective effect and its chemopreventive activity is associated with p53-mediated apoptosis during early hepatocarcinogenesis.

No comments:

Post a Comment