GARLIC JOINS THE FIGHT AGAINST CANCER
Findings reveal the vegetable contains a compound that’s able to assist in overcoming this group of diseases, writes Nontando Mposo
GARLIC is a common cooking ingredient that is used by many because of its distinct flavour and aroma. The plant has also been recognised since ancient times as a powerful healing food that can treat a wide range of conditions and diseases.
Now recent research findings by Dr Catherine Kaschula, a lecturer at the University of Cape Town, has revealed just how the bulb-shaped plant contains cancer-fighting properties.
Kaschula and her research team established that a natural compound found in crushed cloves of garlic, known as ajoene, is able to kill cancer cells.
The word “ajoene”, is derived from “ajo”, the Spanish word for garlic, and refers to the main compound produced in crushed and heated garlic.
Using the compound on breast and oesophageal cancer cells, the research team showed that ajoene was not only toxic to cancer cells, but also established how the compound interferes with protein folding which leads to the death of cancer cells.
Kaschula presented her findings at the Cancer Association of SA (Cansa) Research in Action Conference in Stellenbosch in July.
Speaking from her office at UCT, she said the researchers made use of synthetic organic chemistry techniques to “clip” a fluorescent tag onto ajoene, which enabled them to track its movement in the cancer cell by visualising the fluorescence. This unveiled that ajoene penetrates cancer cells and attaches itself to newly synthesised proteins causing the cells to die.
While this specific research was only conducted on breast and oesophageal cancer cells, previous studies have shown that ajoene is also toxic to other cancer cell types, explains Kaschula.
Their findings provide a detailed explanation as to why ajoene is toxic to cancer cells. “The ‘tagged’ ajoene was found to localise a specific organelle in the cancer cell called the Endoplasmic Reticulum. This is a place where newly synthesised proteins are folded before they are sent to their specific sites,” says Kaschula.
“We found that ajoene exerts its toxic effect by interfering with protein folding in the endoplasmic reticulum of the cancer cell.
“This leads to an accumulation of misfolded proteins which aggregate together and the aggregates are toxic to the cells. So in a way it is the very own proteins of the cancer cell which end up poisoning it.”
Kaschula said that one clove of garlic, which weighs more or less two grams, crushed and heated to 80 degrees in about 50ml of sauce would produce enough ajoene to bring about the effects they observed in the lab.
“By cooking garlic you are actually doing some kitchen chemistry. Crushing releases a natural antibiotic called allicin, which is then converted into the cancer-fighting chemical ajoene upon heating (cooking).
“The plant is not generating the ajoene for our cancer prevention benefit but, being a plant, it doesn’t want to be eaten by microorganisms… therefore it generates these toxic substances as a protective measure in self-defence.
“A lot of cancer therapeutics have come from plants, where these toxic chemicals are specifically produced,” she says.
“Essentially, what it boils down to is that it has been known for quite some time that garlic has cancer-preventative qualities.
“There is a lot of literature out there where researchers have found that people who consume high amounts of garlic have a lower risk of developing certain cancers, which are mainly of the gastrointestinal tract,” Kaschula says.
“It’s quite interesting how a lot of foods are actually medicine, and garlic is an example of a food we obtain through our diet which contains potent chemicals that have cancer-fighting properties.
“Garlic has so many interesting-properties that I feel this may just be the beginning of what I can find out… I really feel like I’ve just scratched the surface.
“There are a lot of beneficial health effects of garlic, and cancer prevention is just one of them.
“As I studied the plant, I was amazed by how many different biological processors these compounds are able to modulate.
“Cancer prevention has been my focus, but I have also started looking at how it’s able to modulate different immune responses as well,” Kaschula said.