ergo-log.com

Definition: "An ergogenic aid is any substance or phenomenon that enhances performance "

28.09.2015

Lignan in Arctium lappa makes fasting deadlier for cancer cells

A low-carb diet or fasting inhibits the growth of many kinds of cancer cells, but some types of cancer are resistant to this. Supplementation with arctigenin, a lignan found in the plant Arctium lappa, undermines the resistance of these persistent forms of cancer. Researchers at Toyama Medical And Pharmaceutical University in Japan drew this conclusion from in-vitro and animal studies that they published in Cancer Research.

Arctium lappa
Arctium lappa goes by the common name of Burdock in English. You can buy extracts of the plant in any supplements shop or drugstore. They are supposed to help against a greasy skin, but traditional healers in Asia also use them a remedy for skin rashes, soar throat, arthritis, infertility and low sex drive.

The main active ingredients in Arctium lappa, which by the way grows in large parts of Europe and Asia, are lignans, a few of which are shown below.

1 = Arctigenin, 2 = arctiin, 3 = nordihydroguaiaretic acid, 4 = secoisolariciresinol, 5 = sesamin.

Cancer and fasting
Cancer cells are more likely to succumb to chemotherapy and attacks from the immune system if they are unable to absorb much glucose. That's probably why a lifestyle that includes lots of exercise and a moderate calorie intake reduces the chance of developing cancer, scientists think.

Some cancer cells, however, are capable of defending themselves against a low glucose supply. They increase their synthesis of the anabolic signal molecule Akt. [Cancer Res. 2000 Nov 1;60(21):6201-7.]

The researchers screened extracts of 500 plants that are used in traditional Japanese Kampo medicine, searching for substances that sabotage the process whereby cancer cells make themselves resistant against fasting. This was how they came across arctigenin in Arctium lappa.

Study
The researchers did their experiment on PANC-1, a type of pancreatic cancer cell that is resistant to fasting. The Japanese exposed these cancer cells to arctigenin under different sets of conditions.

Results
The figure below shows that arctigenin killed cancer cells when they had serum and amino acids but no glucose available.

The figure above shows how arctigenin probably works. It reduces the activity of Akt.

Two other lignans in Arctium lappa, nordihydroguaiaretic acid and sesamin, also had some cancer-inhibitory effect according to the Japanese in-vitro studies, but the effect was much less than that of arctigenin. Secoisolarirecinol and arctiin had no effect on the cancer cells at all.

In an animal study, the researchers implanted PANC-1 cancer cells in mice and then waited for 64 days. The researchers injected a solution containing arctigenin daily into the small intestine [Treated] of half of the animals. The human equivalent of the dose they used would be about 20-30 mg per day.

We have no idea a) whether it's possible to ingest this much arctigenin by taking Arctium lappa supplements or b) how fast enzymes convert arctigenin into inactive substances in humans.

Arctigenin did inhibit the growth of the cancer cells.

Conclusion
The researchers hope that arctigenin will prove useful in combatting cancer. It has few side effects and may help to make regular therapies more effective.

The researchers were funded by the Japanese government.

Source:
Cancer Res. 2006 Feb 1;66(3):1751-7.

More:
Arctigenin, the endurance drug in Arctium lappa 04.10.2015
Arctium lappa for more testosterone 11.05.2012

Archives:
Cancer Prevention

This is how physical exercise clears up tumours Physical exertion transforms the body into a hostile environment for cancer cells. This animal study tells how.	Every intensive training session is a chemo lite Every time you do intensive exercise, your body produces substances that kill cancer cells.	'Physical activity should be a standard part of cancer care' "Many treatments may increase survival, but at a cost of quality of life; physical activity may not only extend life but may also enhance its quality."