
Cognitive damage halted by THC in marijuana, Israeli reseachers discover

“An Israeli researcher has found that tiny doses of the psychoactive chemical in marijuana helps the brain of mice combat injury.”
“The words “marijuana” and “brain damage” usually go in that order in medical literature. An Israeli researcher has flipped them around, finding that THC, the active ingredient in marijuana, may arrest some forms of brain damage in mice. The loco weed already is favored by those who suffer from chronic diseases, not to mention fans of Cypress Hill, Bob Marley and the Grateful Dead. But pharmacologist Josef Sarne of Tel Aviv University found that a minuscule amount of tetrahydrocannabinol may protect the brain after injuries from seizures, toxic drug exposure or a lack of oxygen.” |
“Extremely low doses of THC, the psychoactive component of marijuana, protects the brain from long-term cognitive damage in case of injury from hypoxia (lack of oxygen), seizures, or toxic drugs, a new study has claimed.
Medical cannabis is often used by sufferers of chronic ailments, including cancer and post-traumatic stress disorder, to combat pain, insomnia, lack of appetite, and other symptoms.
Now, Professor Yosef Sarne of Tel Aviv University’s Adelson Center for the Biology of Addictive Diseases at the Sackler Faculty of Medicine in US found the drug has neuroprotective qualities as well.
Previous studies focused on injecting high doses of THC within a very short time frame approximately 30 minutes before or after injury.
Sarne’s current research, published in the journals Behavioural Brain Research and Experimental Brain Research, demonstrates that even extremely low doses of THC around 1,000 to 10,000 times less than that in a conventional marijuana cigarette administered over a wide window of 1 to 7 days before or 1 to 3 days after injury can jump start biochemical processes which protect brain cells and preserve cognitive function over time.
This treatment, especially in light of the long time frame for administration and the low dosage, could be applicable to many cases of brain injury and be safer over time, Sarne said.
While performing experiments on the biology of cannabis, researchers found that low doses of the drug had a big impact on cell signalling, preventing cell death and promoting growth factors.
This finding led to a series of experiments designed to test the neuroprotective ability of THC in response to various brain injuries.
In the lab, the researchers injected mice with a single low dose of THC either before or after exposing them to brain trauma. A control group of mice sustained brain injury but did not receive the THC treatment.”
http://www.indianexpress.com/news/marijuana-component-can-halt-brain-damage/1123274/
“Though marijuana is a well-known recreational drug, extensive scientific research has been conducted on the therapeutic properties of marijuana in the last decade. Medical cannabis is often used by sufferers of chronic ailments, including cancer and post-traumatic stress disorder, to combat pain, insomnia, lack of appetite, and other symptoms.
Now Prof. Yosef Sarne of Tel Aviv University’s Adelson Center for the Biology of Addictive Diseases at the Sackler Faculty of Medicine says that the drug has neuroprotective qualities as well. He has found that extremely low doses of THC—the psychoactive component of marijuana—protects the brain from long-term cognitive damage in the wake of injury from hypoxia (lack of oxygen), seizures, or toxic drugs. Brain damage can have consequences ranging from mild cognitive deficits to severe neurological damage.
Previous studies focused on injecting high doses of THC within a very short time frame—approximately 30 minutes—before or after injury. Prof. Sarne’s current research, published in the journals Behavioural Brain Research and Experimental Brain Research, demonstrates that even extremely low doses of THC—around 1,000 to 10,000 times less than that in a conventional marijuana cigarette—administered over a wide window of 1 to 7 days before or 1 to 3 days after injury can jumpstart biochemical processes which protect brain cells and preserve cognitive function over time.
This treatment, especially in light of the long time frame for administration and the low dosage, could be applicable to many cases of brain injury and be safer over time…”
More: http://medicalxpress.com/news/2013-05-doses-marijuana-component-brain-injury.html
“Though marijuana is a well-known recreational drug, extensive scientific research has been conducted on the therapeutic properties of marijuana in the last decade. Medical cannabis is often used by sufferers of chronic ailments, including cancer and post-traumatic stress disorder, to combat pain, insomnia, lack of appetite and other symptoms.
Now Prof. Yosef Sarne of Tel Aviv Univ.’s Adelson Center for the Biology of Addictive Diseases at the Sackler Faculty of Medicine says that the drug has neuroprotective qualities as well. He has found that extremely low doses of THC — the psychoactive component of marijuana — protects the brain from long-term cognitive damage in the wake of injury from hypoxia (lack of oxygen), seizures or toxic drugs. Brain damage can have consequences ranging from mild cognitive deficits to severe neurological damage.
Previous studies focused on injecting high doses of THC within a very short time frame — approximately 30 minutes — before or after injury. Sarne’s current research, published in the journals Behavioural Brain Research and Experimental Brain Research, demonstrates that even extremely low doses of THC — around 1,000 to 10,000 times less than that in a conventional marijuana cigarette — administered over a wide window of one to seven days before or one to three days after injury can jumpstart biochemical processes which protect brain cells and preserve cognitive function over time.
This treatment, especially in light of the long time frame for administration and the low dosage, could be applicable to many cases of brain injury and be safer over time, Sarne says.”
More: http://www.laboratoryequipment.com/news/2013/05/marijuanas-thc-can-halt-brain-damage
“The term ‘endocannabinoid’ – originally coined in the mid-1990s after the discovery of membrane receptors for the psychoactive principle in Cannabis, Delta9-tetrahydrocannabinol and their endogenous ligands – now indicates a whole signalling system that comprises cannabinoid receptors, endogenous ligands and enzymes for ligand biosynthesis and inactivation. This system seems to be involved in an ever-increasing number of pathological conditions. With novel products already being aimed at the pharmaceutical market little more than a decade since the discovery of cannabinoid receptors, the endocannabinoid system seems to hold even more promise for the future development of therapeutic drugs. We explore the conditions under which the potential of targeting the endocannabinoid system might be realized in the years to come.” http://www.ncbi.nlm.nih.gov/pubmed/15340387
“A number of investigations have shown that CB2 receptor activation has anti-inflammatory therapeutic potential in various CNS diseases, such as multiple sclerosis, traumatic brain injury and Alzheimer’s disease. Because inflammatory responses have been shown to be important contributors to secondary injury following cerebral ischemia; the CB2 receptor has been investigated as a potential therapeutic target in stroke…
The most striking changes were obtained by combing a CB1 antagonist with a CB2 agonist. This combination elevated the cerebral blood flow during ischemia and reduced infarction by 75%…during cerebral ischemia/reperfusion injury, inhibition of CB1 receptor activation is protective while inhibition of CB2 receptor activation is detrimental.
The greatest degree of neuroprotection was obtained by combining an inhibitor of CB1 activation with an exogenous CB2 agonist.
In conclusion, the results of this investigation demonstrate dynamic changes in the expression of CB1 and CB2 receptors during cerebral ischemic/reperfusion injury in mice. The effects of stimulation of these receptors on damage ischemia/reperfusion injury differed dramatically. Stimulation of the CB2 receptor was found to be neuroprotective, while inhibition of the CB1 receptor was also protective,too. The combination of a CB2 agonist and a CB1 antagonist provided the greatest degree of protection and indicated a synergistic effect derived from combining these agents. Therefore, changing the balance of stimulation of these receptors by endogenous cannabinoids may provide an important therapeutic strategy during stroke.”
Full text: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2577828/
Results from the present study prove the selective involvement of PPARγ in the anti-inflammatory and neuroprotective effects of CBD here observed either in vitro and in vivo. In addition, CBD significantly promoted neurogenesis in Aβ injured rat hippocampi, much expanding its already wide spectrum of beneficial actions exerted in AD models, a non negligible effect, due to its capability to activate PPARγ.
In conclusion, results of the present research demonstrate that CBD may exert protective functions through a PPARγ dependent activation, which leads to a reduction in reactive gliosis and consequently in neurodegeneration. Moreover, in the current experimental conditions this phytocannabinoid appears to stimulate neurogenesis since it increases DCX immunopositive cell proliferation rate in rat DG.
Innovative therapeutic approaches which could significantly improve AD course require new molecules that will be able to have an impact on different pathological pathways, which converge at the progressive neurological decline. CBD has shown a capability to profoundly reduce reactive astrogliosis and to guarantee both direct and indirect neuronal protection in Aβ induced neuroinflammation/neurodegeration. So far, the lack of understanding of the precise molecular mechanism involved in CBD pharmacological actions, has had limited interest and has puzzled investigators.
Currently, findings of the present study throw some light on the issue, and frame CBD as a new PPARγ activator.”
“To investigate the mechanisms involved in cannabidiol (CBD)-induced neuroprotection in hypoxic-ischemic (HI) immature brain, forebrain slices from newborn mice underwent oxygen and glucose deprivation in the presence of vehicle, or CBD alone or with selective antagonists of cannabinoid CB(1) and CB(2), and adenosine A(1) and A(2) receptors. CBD reduced acute (LDH efflux to the incubation medium) and apoptotic (caspase-9 concentration in tissue) HI brain damage by reducing glutamate and IL-6 concentration, and TNFalpha, COX-2, and iNOS expression. CBD effects were reversed by the CB(2) antagonist AM630 and by the A(2A) antagonist SCH58261. The A(1A) antagonist DPCPX only counteracted the CBD reduction of glutamate release, while the CB(1) antagonist SR141716 did not modify any effect of CBD. In conclusion, CBD induces robust neuroprotection in immature brain, by acting on some of the major mechanisms underlying HI cell death; these effects are mediated by CB(2) and adenosine, mainly A(2A), receptors.”
“These results provide evidence that the cannabinoid system can serve to protect the brain against neurodegeneration.”
“In summary, we have shown that in an in vivo model of neurodegeneration Δ9-THC reduces neuronal damage via a CB1-receptor-mediated mechanism. This holds in both the acute and late phase after induction of excitotoxicity. Δ9-THC inhibits astrogliosis via a non-CB1-receptor-controlled mechanism. The results strengthen the concept that the endogenous cannabinoid system may serve to establish a defense system for the brain. This system may be functional in several neurodegenerative diseases in which excitotoxicity is thought to play a role, such as amyotrophic lateral sclerosis, Huntington’s and Parkinson’s diseases, and also in acute neuronal damage as found in stroke and traumatic brain injury. It is conceivable that the endogenous cannabinoid system can be exploited for therapeutic interventions in these types of primarily incurable diseases.”