Veggie fans can already point to some cancer-fighting properties of 3,3'-diindolylmethane (DIM), a chemical produced from the compound indole-3-carbinol when Brassica vegetables such as broccoli, cabbage and kale are chewed and digested. Animal studies have shown that DIM can actually stop the growth of certain cancer cells.
This new study in mice, published online today (Monday, Aug. 20) in the Journal of Nutritional Biochemistry, shows that DIM may help boost the immune system as well.
"We provide clear evidence that DIM is effective in augmenting the immune response for the mice in the study, and we know that the immune system is important in defending the body against infections of many kinds and cancer," said Leonard Bjeldanes, UC Berkeley professor of toxicology and principal investigator of the study. "This finding bodes well for DIM as a protective agent against major human maladies."
Previous studies led by Bjeldanes and Gary Firestone, UC Berkeley professor of molecular and cell biology, have shown that DIM halts the division of breast cancer cells and inhibits testosterone, the male hormone needed for growth of prostate cancer cells.
In the new study, the researchers found increased blood levels of cytokines, proteins which help regulate the cells of the immune system, in mice that had been fed solutions containing doses of DIM at a concentration of 30 milligrams per kilogram. Specifically, DIM led to a jump in levels of four types of cytokines: interleukin 6, granulocyte colony-stimulating factor, interleukin 12 and interferon-gamma.
"As far as we know, this is the first report to show an immune stimulating effect for DIM," said study lead author Ling Xue, who was a Ph.D. student in Bjeldanes' lab at the time of the study and is now a post-doctoral researcher in molecular and cell biology at UC Berkeley.
In cell cultures, the researchers also found that, compared with a control sample, a 10 micromolar dose of DIM doubled the number of white blood cells, or lymphocytes, which help the body fight infections by killing or engulfing pathogens. (A large plateful of broccoli can yield a 5-10 micromolar dose of DIM.)
When DIM was combined with other agents known to induce the proliferation of lymphocytes, the effects were even greater than any one agent acting alone, with a three- to sixfold increase in the number of white blood cells in the culture.
"It is well-known that the immune system can seek out and destroy tumor cells, and even prevent tumor growth," said Xue. "An important type of T cell, called a T killer cell, can directly kill certain tumor cells, virally infected cells and sometimes parasites. This study provides strong evidence that could help explain how DIM blocks tumor growth in animals."
DIM was also able to induce higher levels of reactive oxygen species (ROS), substances which must be released by macrophages in order to kill some types of bacteria as well as tumor cells. The induction of ROS - three times that of a control culture - after DIM was added to the cell culture signaled the activation of macrophages, the researchers said.
"The effects of DIM were transient, with cytokine and lymphocyte levels going up and then down, which is what you'd expect with an immune response," said Bjeldanes. "Interestingly, to obtain the effects on the immune response, DIM must be given orally, not injected. It could be that the metabolism of the compound changes when it is injected instead of eaten."
To examine the anti-viral properties of DIM, the researchers infected mice with reoviruses, which live in the intestines but are not life-threatening. Mice that had been given oral doses of DIM were significantly more efficient in clearing the virus from their gut - as measured by the level of viruses excreted in their feces - than mice that had not been fed DIM.
"This means that DIM is augmenting the body's ability to defend itself by inhibiting the proliferation of the virus," said Bjeldanes. "Future studies will determine whether DIM has similar effects on pathogenic viruses and bacteria, including those that cause diarrhea."
The discovery of DIM's effects on the immune system helps bolster its reputation as a formidable cancer-fighter, the researchers said. "This study shows that there is a whole new universe of cancer regulation related to DIM," said Firestone, who also co-authored the new study. "There are virtually no other agents known that can both directly shut down the growth of cancer cells and enhance the function of the immune system at the same time."
Sarah Yang | EurekAlert!
Seeing on the Quick: New Insights into Active Vision in the Brain
15.08.2018 | Eberhard Karls Universität Tübingen
New Approach to Treating Chronic Itch
15.08.2018 | Universität Zürich
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
15.08.2018 | Physics and Astronomy
15.08.2018 | Earth Sciences
15.08.2018 | Physics and Astronomy