Une étude americain vient de prouver que le réglisse (3arq sous, ou 7arq sous) protége le corps du Cancer!
le réglisse : http://pharm1.pharmazie.uni-greifswald.de/systematik/7_bilder/yamasaki/GlycyrrhizaD.jpg
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Licorice Could Help Prevent Colorectal Cancer
chemical compound found in licorice (Glycyrrhiza glabra root) could be used in the preventive therapies of colorectal cancer (the second leading cause of cancer deaths in the US), as a study conducted by The Vanderbilt University Medical Center and published in the Journal of Clinical Investigation reports. Raymond Harris, M.D., Ming-Zhi Zhang, M.D., and colleagues, trying to develop new preventing therapies, show how inhibiting the enzyme 11β-hydroxysteroid dehydrogenase type 2 (11βHSD2) either by treatment with a natural compound found in licorice (glycyrrhizic acid) or by silencing the 11βHSD2 gene prevents colorectal cancer progression in mice predisposed to the disease.
COX-2 (cyclooxygenase 2 enzyme) produces prostaglandins, which aid the progression of colorectal cancer. Used for their inhibitory attributes against the enzyme, non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or selective COX-2 inhibitors like Vioxx or Celebrex, have limited utility in chemoprevention due to their severe side-effects (like gastrointestinal irritation, cardiovascular events, and immunosuppression).
Harris and Zhang (both nephrologists and members of the Vanderbilt-Ingram Cancer Center), while studying the regulation of COX-2 in the kidney, found that the inhibition of 11βHSD2 stop the expression of the enzyme in this organ. Since only the kidney and the colon have a high expression of 11βHSD2, the conclusion was that there is a correlation between these two enzymes, after the study of their expression in human colon polyps and in the colons of mice predisposed to colon cancer.
They succeeded in inhibiting 11βHSD2 with glycyrrhizic acid (found in licorice) and by silencing the 11βHSD2 gene. The treatments, by inhibiting the production of prostaglandin E2 produced by the COX-2 enzyme, prevented the formation of polyps and stopped tumor growth and metastasis.
While the common drugs used in chemoprevention have serious side effects that affect the whole body, suppressing 11βHSD2 only has effects specific to the tissues in which is highly expressed (kidney, colon). Nonetheless, licorice might have its own side effects, excessive consumption leading to low blood potassium and increases in blood pressure; Harris noted that These are relatively minor compared to the cardiovascular side effects of COX-2 inhibitors. We didnt see (these side effects) in the mice we treated but it would be something to be aware of, and something that could easily be treated with a diuretic.
The researchers are now continuing to investigate the mechanism of 11βHSD2, trying to develop better inhibitors for it and also investigating the enzymes role in lung and other forms of cancer, as told by dr. Zhang: We think we can make (an inhibitor) that is more specific and has better delivery to the target tissues.
le réglisse : http://pharm1.pharmazie.uni-greifswald.de/systematik/7_bilder/yamasaki/GlycyrrhizaD.jpg
____
Licorice Could Help Prevent Colorectal Cancer
chemical compound found in licorice (Glycyrrhiza glabra root) could be used in the preventive therapies of colorectal cancer (the second leading cause of cancer deaths in the US), as a study conducted by The Vanderbilt University Medical Center and published in the Journal of Clinical Investigation reports. Raymond Harris, M.D., Ming-Zhi Zhang, M.D., and colleagues, trying to develop new preventing therapies, show how inhibiting the enzyme 11β-hydroxysteroid dehydrogenase type 2 (11βHSD2) either by treatment with a natural compound found in licorice (glycyrrhizic acid) or by silencing the 11βHSD2 gene prevents colorectal cancer progression in mice predisposed to the disease.
COX-2 (cyclooxygenase 2 enzyme) produces prostaglandins, which aid the progression of colorectal cancer. Used for their inhibitory attributes against the enzyme, non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or selective COX-2 inhibitors like Vioxx or Celebrex, have limited utility in chemoprevention due to their severe side-effects (like gastrointestinal irritation, cardiovascular events, and immunosuppression).
Harris and Zhang (both nephrologists and members of the Vanderbilt-Ingram Cancer Center), while studying the regulation of COX-2 in the kidney, found that the inhibition of 11βHSD2 stop the expression of the enzyme in this organ. Since only the kidney and the colon have a high expression of 11βHSD2, the conclusion was that there is a correlation between these two enzymes, after the study of their expression in human colon polyps and in the colons of mice predisposed to colon cancer.
They succeeded in inhibiting 11βHSD2 with glycyrrhizic acid (found in licorice) and by silencing the 11βHSD2 gene. The treatments, by inhibiting the production of prostaglandin E2 produced by the COX-2 enzyme, prevented the formation of polyps and stopped tumor growth and metastasis.
While the common drugs used in chemoprevention have serious side effects that affect the whole body, suppressing 11βHSD2 only has effects specific to the tissues in which is highly expressed (kidney, colon). Nonetheless, licorice might have its own side effects, excessive consumption leading to low blood potassium and increases in blood pressure; Harris noted that These are relatively minor compared to the cardiovascular side effects of COX-2 inhibitors. We didnt see (these side effects) in the mice we treated but it would be something to be aware of, and something that could easily be treated with a diuretic.
The researchers are now continuing to investigate the mechanism of 11βHSD2, trying to develop better inhibitors for it and also investigating the enzymes role in lung and other forms of cancer, as told by dr. Zhang: We think we can make (an inhibitor) that is more specific and has better delivery to the target tissues.