Response of Liver Nucleic Acids and Lipids in Rats Fed Cycas circinalis L. Endosperm or Cycasin

Summary

The feeding of ground Cycas circinalis L. endosperm or cycasin, a glyco-side isolated from the cycad endosperm, both of which produce liver and kidney tumors in rats and liver tumors in guinea pigs, produces an almost identical loss of RNA and phospholipids from rat liver cells. The ground endosperm is considerably more active, based on its cycasin content, than is cycasin. These changes correlate closely with loss of cyto-plasmic basophilia, as observed with the light microscope, and with loss of ribosomes from the parallel arrays of the lipoprotein-rich endoplasmic reticular membrane, as observed with the electron microscope. No effect on DNA concentration occurred. Liver cholesterol and neutral glycerides were increased by cycasin feeding.

The authors wish to thank Dr. John C. Keresztesy for preparation of the ground cycad meal, Mrs. Alice J. Hurlebaus for most competent technical assistance in these studies, and Dr. A. Kobayashi, Dept. of Agricultural Biochemistry, Univ. of Hawaii, for analysis of the cycad meal for cycasin.