October 8, 2013
Marijuana Compound Shows Promise In The Fight Against Multiple Sclerosis
April Flowers for redOrbit.com - Your Universe Online
Multiple Sclerosis, an inflammatory disease in which the immune system attacks the nervous system, results in a wide range of debilitating motor, physical and mental problems. Scientists still have no idea why someone gets the disease or how to treat it.
A new study, led by Tel Aviv University's Dr. Miriam and Sheldon G. Adelson Center for the Biology of Addictive Diseases and Sackler Faculty of Medicine, reveals some of the chemical compounds found in marijuana can help treat MS-like diseases in mice. The research team, which included scientists from Tel Aviv University and the Weizmann Institute of Science, said the compounds prevent inflammation in the brain and spinal cord. Their results were published in the Journal of Neuroimmune Pharmacology.
"Inflammation is part of the body's natural immune response, but in cases like MS it gets out of hand," says Dr. Ewa Kozela. "Our study looks at how compounds isolated from marijuana can be used to regulate inflammation to protect the nervous system and its functions."
There is a strong tradition of marijuana research in Israel. For example, in 1964 Israeli scientists Raphael Mechoulam and Yechiel Gaoni discovered THC, or tetrahydrocannabinol. This kick-started the global scientific study of the plant and its chemical components. So far, around 70 compounds - called cannabinoids - have been identified that are unique to cannabis and have interesting biological effects. Professor Vogel, in the 1990s, was among the first to describe THC-acting molecules, called endocannabinoids, in the human body.
The second most plentiful and potent cannabinoid in marijuana, after THC, is cannabidiol, or CBD. CBD is of particular interest to the TAU researchers because it offers medicinal benefits without the controversial mind-altering effects of THC.
CBD was shown to help treat MS-like symptoms in mice in a 2011 TAU study. The compound prevented immune cells in the bodies of the mice from transforming and attacking the insulating covers of nerve cells in the spinal cord. The researchers induced an MS-like condition in the mice by partially paralyzing their limbs, then injected them with CBD. The mice regained movement, first tail twitching and then beginning to walk without a limp following the treatment. The mice treated with CBD also showed less inflammation in the spinal cord than the untreated mice.
The current study was designed to see if the known anti-inflammatory properties of THC and CBD could be applied to the treatment of inflammation associated with MS. To investigate, they turned to the immune system.
The team isolated immune cells from mice that specifically target and harm the brain and spinal cord and treated the cells with either CBD or THC. They found that in both cases the immune cells produced fewer inflammatory molecules, particularly one called interleukin 17, or IL-17. IL-17 has a strong association with MS and is very harmful to nerve cells and their insulating covers. The presence of CBD or THC restrains the immune cells from triggering the production of inflammatory molecules, according to the research team. They also limit the molecules' ability to reach and damage the brain and spinal cord.
The team says further research is required to prove the effectiveness of cannabinoids in treating MS in humans. They do believe their research offers hope, however. CBC and THC are already prescribed in many countries for the treatment of MS symptoms, including pain and muscle stiffness.
"When used wisely, cannabis has huge potential," says Kozela, who previously studied opiates like morphine, derived from the poppy plant. "We're just beginning to understand how it works."