Many phytoantioxidants have therapeutic drawbacks due to their potent prooxidant bioactivity. It is hypothesized that phytoantioxidants (PAO) are beneficial only to the early-stage diabetes mellitus (DM) and will become ineffective once renopathy occurs. Gallic acid, rutin, EGCG, ferulic acid (FA), and quercetin were tried on the streptozotocin (STZ)-induced DM rat model for a 28 week experimental period. All of these PAO were shown to be ineffective for hypoglycemic action. The incidence of cataract (50%), injured glomerules, and renal cell carcinoma (RCC) was very common, among which the most severely affected involved the quercetin- and the FA-treated groups. The tumorigenicity of ferulic acid is still unclear. However, for quercetin, this can be attributted to (i) the prooxidant effect, (ii) the insulin-secretagogue bioactivity, and (iii) the competitive and noncompetitive inhibition on the O-methyltransferase to enhance the estradiol-induced tumorigenesis. Conclusively, quercetin and FA are able to aggravate, if not induce, nephrocarcinoma. It is tie to reevaluate the tumorigenic detrimental effect of PAO, especially those exhibiting prooxidant bioactivity.
All Science Journal Classification (ASJC) codes
- Agricultural and Biological Sciences(all)