Therapeutic Grade Lemon and Orange essential oils contains approximately 59-73% and 85-96% d-limonene (DL) respectively and d-limonene is a monoterpene (MT). Lemon essential Oil has an proximately ORAC of 6,619 (TE/L) and is cold-pressed from the rinds of lemons. Jean Valnet MD estimated that it takes 3,000 lemons to produce one kilo of oil. Orange Essential Oil has an proximately ORAC of 18,898 (TE/L).
Studies have shown that limonene and monoterpenes specifically, affect positively liver enzymes. Limonen increase the levels of liver enzymes involved in detoxifying carcinogens. The Glutathione S-transferase (GST) is a system which eliminates carcinogens. Limonene seems to promote the GST system in the liver and small bowel, thereby decreasing the damaging effects of carcinogens. Animal studies demonstrated that dietary limonene reduced mammary tumor growth.
A study by Mark Brudnak, Ph.D. ND explains how monoterpenes (MTs), found in essential oils offer hope in the struggle to prevent and treat tumors. The best news is that DL and POH can not only prevent but also treat altered cells. The MTs can act before a cancer is established and where degeneration is already present, they can cause a regression of the tumor.
First, during the initiation phase of carcinogenesis they induce Phase-II carcinogen-metabolizing enzymes, resulting in carcinogen detoxification. An example of such a Phase-II enzyme would be glutathione S-transferase.
Second, post initiation phase, they have been shown to increase cell redifferentiation. This causes the cells to take on a more normal morphology.
Third, they can induce apoptosis in otherwise immortalized (see above) cells.
Fourth, they have been shown to inhibit the isoprenylation of the cellular products (Ras ) of oncogenes. Simply put, the proteins from oncogenes, which on the whole are cell-growth regulating proteins, need to be modified by a process called prenylation in order to be placed in a membrane where they are active. If the proteins from oncogenes do not undergo isoprenylation, they do not cause the cell to behave erratically and hence cell degeneration inhibition results.
Cancer Chemoprevention and Therapy by Monoterpenes
Department of Human Oncology, University of Wisconsin, Madison 53792, USA
Monoterpenes are found in the essential oils of many plants including fruits, vegetables, and herbs. They prevent the carcinogenesis process at both the initiation and promotion/progression stages. In addition, monoterpenes are effective in treating early and advanced cancers.
Monoterpenes such as limonene and perillyl alcohol have been shown to prevent mammary, liver, lung, and'other cancers. These compounds have also been used to treat a variety of rodent cancers, including breast and pancreatic carcinomas. In addition, in vitro data suggest that they may be effective in treating neuroblastomas and leukemias. Both limonene and perillyl alcohol are currently being evaluated in phase-I clinical trials in advanced cancer patients.
The monoterpenes have several cellular and molecular activities that could potentially underlie their positive therapeutic index. The monoterpenes inhibit the isoprenylation of small G-proteins. Such inhibitions could alter signal transduction and result in altered gene expression.
The results of a new gene expression screen-subtractive display-have identified or confirmed several up or downregulated genes in regressing mammary carcinomas. For example, these regressing tumors overexpress the mannose 6-phosphate/IGF II receptor. The product of the gene both degrades the mammary tumor mitogen IGF II and activates the cytostatic factor TGF-beta.
These and other alterations in the gene expression of mammary carcinomas lead to a G1 cell cycle block, followed by apoptosis, redifferentiation, and finally complete tumor regression in which tumor parenchyma is replaced by stromal elements. It is likely that monoterpenes prevent mammary cancer during their progression stage by mechanisms similar to those that occur during therapy. In contrast, prevention of mammary cancer by polycyclic hydrocarbons such as 7,12-dimethylbenz[a]anthracene occur by the induction of detoxifying phase-II hepatic enzymes.
This may not be the complete list of references from this article:
TE/L is expressed as micromole Trolox equivalent per liter
Cancer-Preventing Properties of Essential Oil Monoterpenes D-Limonene and Perillyl Alcohol. by Mark Brudnak, Ph.D. ND. listed in cancer, originally published in issue 53 - June 2000
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