Aerobic glycolysis, tumors

Berberine inhibits oxidative decarboxylation of yeast pyruvic acid (310) the same dose has, however, no effect upon aerobic glycolysis, Warburg s respiratory enzymes, indophenol oxidase, etc. Berberine and tetrahydroberberine have an inhibitory effect on oxidation of (+ )-alanine in rat kidney homogenates (498). Berberine and palmatine show a specific inhibitory effect upon cholinesterase in rabbit spleen and on pseudocholinesterase in horse serum (499). Berberine inhibits cellular respiration in ascitic tumors and even in tissue cultures (500-502). The specific toxic effect of berberine on the respiration of cells of ascitic tumors in mice was described (310). The glycolysis was not found to be affected, but the uptake of oxygen was smaller. Fluorescence was used in order to demonstrate berberine in cellular granules. Hirsch (503) assumed that respiration is inhibited by the effect of berberine on the yellow respiratory enzymes. Since the tumorous tissue contains a smaller number of yellow respiratory enzymes than normal tissue it is more readily affected by berberine. Subcutaneous injections of berberine, palmatine, or tetrahydropalmatine significantly reduce the content of ascorbic acid in the suprarenals, which is not affected by hypophysectomy (504). 

It is accepted that the cells in tumors in vivo undergo high rates of aerobic glycolysis to produce lactate. A major substrate appears to be glutamine derived from the degradation of muscle proteins (Newsholme et al., 1985 McKeehan,... 

Suolinna, E-N., Lang, D. and Packer, E. (1974). Quercetin, an artificial regulator of the high aerobic glycolysis of tumor cells. J. Natl. Cancer Inst. 53, 1515-1519. 

NDGA has been shown to have antitumor activity in vivo and in vitro. It is a powerful cancer antimetabolite producing in vitro complete inhibition of aerobic and anaerobic glycolysis and respiration of suspensions of several types of tumor cells including leukemia types. In vivo, NDGA combined with ascorbic acid is reported to reduce... 

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