Effect
of dietary chlorophyll derivatives
on mutagenesis and tumor cell growth
Chernomorsky
S, Segelman A, Poretz RD. (1999).
Teratog Carcinog Mutagen.19(5):313-22
Much attention in
recent years has been given to the antigenotoxicity of chlorophyll. Chlorophyll,
however, is known to be converted into pheophytin, pyropheophytin, and
pheophorbide in processed vegetable food and following ingestion by humans.
Studies were conducted on the antimutagenic and tumoricidal potencies
of these compounds. All the chlorophyll derivatives tested exhibit identical
antimutagenic effect towards 3-methylcholanthrene (3-MC), suggesting that
the porphyrin nucleus may complex directly with the mutagen. It does not
exclude, however, another mechanism of activity involving inactivation
the enzymatic transformation of 3-MC. In contrast, the action of N'-nitro-N'-nitrosoguanidine
(MNNG) depends upon structural differences between the chlorophyll derivatives.
It is significantly lower when the phytol-containing pheophytin and pyropheophytin
are tested as to that of the phytol-lacking pheophorbide. The higher concentrations
of the chlorophyll derivatives were required to reduce the mutagenicity
of MNNG than needed for 3-MC. The cytotoxicity of chlorophyll derivatives
against tumor cells also was evaluated. The cellular uptake and inhibition
of myeloma cell multiplicity were found to be greater for pheophorbide
than for pheophytin. Calculated on the amount of cell associated chlorophyll
derivative, however, pheophytin was more cytostatic/cytotoxic than pheophorbide.
The results presented in this report indicate that food sources that yield
chlorophyll derivatives may play a significant role in cancer prevention.
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