Indole-3-Carbinol, Estrogen and Cancer.
May 13, 2012 Admin 0
Indole-3-Carbinol is a pale coloured solid derived from the breakdown (mostly during cooking and general processing) of glucobrassicin, in cruciferous vegetables such as cabbage, cauliflower and brocolli. Glucobrassicin can be viewed as the precursor of Indole-3-Carbinol. Indole-3-carbinol contains a primary metabolite known as diindoylmethane which is known to augment Oestrogen metabolism and favour greater 2-hydroxy oestrogen production.
Contemporary studies have indicated Indole-3-Carbinol obtained from a diet rich in cruciferous vegetables protects against the risk of oestrogen enhanced cancers such as breast and cervical cancers. Whereas oestrogen can expedite and aid in the proliferation of certain tumours, Indole-3-Carbinol conversely causes an attenuation of growth and induces apoptosis (cell death).
One such study conducted in Scandanavia amongst postmenopausal women showed that the consumption of cruciferous vegetables was associated with a reduced risk of developing breast cancer. Other studies have also demonstrated that Indole-3-Carbinol decreased the migration of MDA-MB-231 (a type of aggressive breast cancer cell).
In a more specific chemo-preventive role, Indole-3-Carbinol can stimulate the production of certain detoxifying enzymes and protect against the potential carcinogenic effects of pesticides, environmental contaminants and certain food toxins. There is also a marked synergistic upregulation of Phase II detoxification enzymes by consumption of processed cruciferous vegetables rich in Indole-3-Carbinol and another phytochemical, Crambene. Crambene, also found in cruciferous vegetables is a nitrile proven for its ability to activate specific detoxification enzymes.
Although not so important, as cruciferous vegetables contain both Indole-3-Carbinol and Crambene, when consumed in combination they offer an induction of Glutathione-S-Transferase and Quinone Oxidoreductase which is observed to be greater than if each compound is ingested alone.
Although Indole-3-Carbinol and other phytonutrients become available by cooking certain vegetables it is not a win-win situation as far as other nutrients are concerned. The cooking of Broccoli can reduce the amount of the antioxidant sulforaphane by as much as 95% according to a study conducted in the Netherlands. They discovered that :
“Consumption of raw broccoli resulted in faster absorption, higher bioavailability, and higher peak plasma amounts of sulforaphane, compared to cooked broccoli.”
A workaround for those concerned in maximising the nutrients available in both raw and cooked cruciferous vegetables is to consume generous portions of both. These don’t have to be at the same sitting and can be split throughout your meal plan in any given week. This we feel will give the best of ‘both worlds’ and enable you to take advantage of what the vegetables offer, nutrient wise. A further recommendation is to buy organic vegetables whenever possible too.
Indole-3-carbinol inhibits MDA-MB-231 breast cancer cell motility and induces stress fibers and focal adhesion formation by activation of Rho kinase activity. (Brew C.T, Aronchik I, Kosco K, McCammon J, Bjeldanes LF, Firestone GL.Department of Molecular and Cell Biology, The University of California at Berkeley.)
Bioavailability and kinetics of sulforaphane in humans after consumption of cooked versus raw broccoli. (Vermeulen M, Vaes WH et al, TNO Quality of Life, AJ Zeist, The Netherlands.)
3,3′-Diindolylmethane and Genistein Decrease the Adverse Effects of Estrogen in LNCaP and PC-3 Prostate Cancer Cells (Smith S, Sepkovic D, Bradlow H, Auborn K. , J. Nutr. 2008 138: 2379-2385)
Indole-3-Carbinol Is a Negative Regulator of Estrogen (Auborn K, Fan S, Rosen, EM, Goodwin L et all, 2003 The American Society for Nutritional Sciences).