Cannabis compound can help cells

“Cannabis has been used recreationally and for medicinal purposes for centuries, yet its 60 plus active components are only partly understood. Now scientists have discovered how a compound in cannabis can help cells to function in our bodies, and aid recovery after a damaging event.

In a paper published in the Journal of Neuroscience, the researchers report on their studies into cannabidiol – a naturally occurring molecule found in cannabis.

Also known as CBD, it is not the constituent that gives the high – that compound is called tetrahydrocannabinol or THC – and so may be more acceptable as a drug treatment.

Both compounds are currently used in a pharmaceutical medicine to help patients relieve pain and other symptoms of Multiple Sclerosis.

Now researchers have discovered how CBD actually works within brain cells.

By interacting with mitochondria – which are the power generators of all cells – it can help maintain normal levels of calcium allowing cells to function properly and providing a greater resistance to damage.

Disturbance of calcium levels has long been associated with a number of brain disorders. So the finding could have implications for the development of new treatments for disorders related to malfunctioning mitochondria.

Dr Bettina Platt, from the University’s School of Medical Sciences, said: “Scientists have known for a long time that cannabidiol can help with pain relief but we never really knew how it worked.

“However we have discovered what it actually does at the cellular level.

“We are hoping that our findings can instruct the development of cannabidiol based treatments for disorders related to mitochondrial dysfunction such as Parkinson’s disease or Huntington’s disease.”

More: http://phys.org/news154280470.html

The pharmacologic and clinical effects of medical cannabis.

“Cannabis, or marijuana, has been used for medicinal purposes for many years. Several types of cannabinoid medicines are available in the United States and Canada. Dronabinol (schedule III), nabilone (schedule II), and nabiximols (not U.S. Food and Drug Administration approved) are cannabis-derived pharmaceuticals.

Medical cannabis or medical marijuana, a leafy plant cultivated for the production of its leaves and flowering tops, is a schedule I drug, but patients obtain it through cannabis dispensaries and statewide programs. The effect that cannabinoid compounds have on the cannabinoid receptors (CB(1) and CB(2) ) found in the brain can create varying pharmacologic responses based on formulation and patient characteristics. The cannabinoid Δ(9) -tetrahydrocannabinol has been determined to have the primary psychoactive effects; the effects of several other key cannabinoid compounds have yet to be fully elucidated. Dronabinol and nabilone are indicated for the treatment of nausea and vomiting associated with cancer chemotherapy and of anorexia associated with weight loss in patients with acquired immune deficiency syndrome. However, pain and muscle spasms are the most common reasons that medical cannabis is being recommended.

Studies of medical cannabis show significant improvement in various types of pain and muscle spasticity. Reported adverse effects are typically not serious, with the most common being dizziness. Safety concerns regarding cannabis include the increased risk of developing schizophrenia with adolescent use, impairments in memory and cognition, accidental pediatric ingestions, and lack of safety packaging for medical cannabis formulations. This article will describe the pharmacology of cannabis, effects of various dosage formulations, therapeutics benefits and risks of cannabis for pain and muscle spasm, and safety concerns of medical cannabis use.”

http://www.ncbi.nlm.nih.gov/pubmed/23386598

Modulation of Cannabinoid Receptor Activation as a Neuroprotective Strategy for EAE and Stroke

“These results provide evidence that alteration of the activation patterns of the various cannabinoid receptors warrant consideration for future therapeutic strategies.

Interest in the medicinal use of Cannabis sativa (marijuana) has a long historical record, extending back thousands of years. In comparison to the extensive history for medicinal applications of marijuana, the existence of an “endocannabinoid system”, with important homeostatic and pathologic functions, has only recently gained appreciation. The endocannabinoid system consists of endogenously produced cannabinoids, their receptors, and the enzymes responsible for their synthesis and degradation…

Although used in ancient Greece, Rome, and China for therapeutic purposes, concern about the use of cannabinoids as a drug of abuse has dampened interest in developing the potential therapeutic benefits of these compounds. However, a better understanding of the biologic effects has led recently to an upsurge in interest for the development of therapeutic drugs through modification of the endocannabinoid system. An additional incentive was provided by the development of synthetic cannabinoid analogs and specific inhibitors of cannabinoid receptors. Several excellent reviews cover the therapeutic potential of cannabinoids….

The present review is focused on the effects of CB2 receptor activation in models of multiple sclerosis (experimental autoimmune encephalomyelitis) and stroke (middle cerebral occlusion/reperfusion).

In summary, selective CB2 receptor agonists and CB1 receptor antagonists have significant potential for neuroprotection in animal models of two devastating diseases that currently lack effective treatment options.”

Full text: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2855650/

Modulation of The Balance Between Cannabinoid CB1 and CB2 Receptor Activation During Cerebral Ischemic/Reperfusion Injury

“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/

Role of endocannabinoid system in mental diseases.

“In the last decade, a large number of studies using Delta9-tetrahydrocannabinol (THC), the main active principle derivative of the marijuana plant, or cannabinoid synthetic derivatives have substantially contributed to advance the understanding of the pharmacology and neurobiological mechanisms produced by cannabinoid receptor activation.

 Cannabis has been historically used to relieve some of the symptoms associated with central nervous system disorders. Nowadays, there are anecdotal evidences for the use of cannabis in many patients suffering from multiple sclerosis or chronic pain. Following the historical reports of the use of cannabis for medicinal purposes, recent research has highlighted the potential of cannabinoids to treat a wide variety of clinical disorders. Some of these disorders that are being investigated are pain, motor dysfunctions or psychiatric illness…

 Considering that cannabis or cannabinoid pharmaceutical preparations may no longer be exclusively recreational drugs but may also present potential therapeutic uses, it has become of great interest to analyze the neurobiological and behavioral consequences of their administration. This review attempts to link current understanding of the basic neurobiology of the endocannabinoid system to novel opportunities for therapeutic intervention and its effects on the central nervous system.”

http://www.ncbi.nlm.nih.gov/pubmed/15325960

Cannabidiol: a promising drug for neurodegenerative disorders?

“Neurodegenerative diseases represent, nowadays, one of the main causes of death in the industrialized country. They are characterized by a loss of neurons in particular regions of the nervous system. It is believed that this nerve cell loss underlies the subsequent decline in cognitive and motor function that patients experience in these diseases. A range of mutant genes and environmental toxins have been implicated in the cause of neurodegenerative disorders but the mechanism remains largely unknown. At present, inflammation, a common denominator among the diverse list of neurodegenerative diseases, has been implicated as a critical mechanism that is responsible for the progressive nature of neurodegeneration.

Since, at present, there are few therapies for the wide range of neurodegenerative diseases, scientists are still in search of new therapeutic approaches to the problem. An early contribution of neuroprotective and antiinflammatory strategies for these disorders seems particularly desirable because isolated treatments cannot be effective.

 In this contest, marijuana derivatives have attracted special interest, although these compounds have always raised several practical and ethical problems for their potential abuse. Nevertheless, among Cannabis compounds, cannabidiol (CBD), which lacks any unwanted psychotropic effect, may represent a very promising agent with the highest prospect for therapeutic use.”

http://www.ncbi.nlm.nih.gov/pubmed/19228180

Cannabidiol Reduces Aβ-Induced Neuroinflammation and Promotes Hippocampal Neurogenesis through PPARγ Involvement

“CBD blunted neuroinflammation sustained by astrocytes through PPARγ selective activation in vitro and in vivo.

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.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3230631/

The development of cannabinoid CBII receptor agonists for the treatment of central neuropathies.

“Cannabinoids have been used in the treatment of nausea and emesis, anorexia and cachexia, tremor and pain associated with multiple sclerosis. These treatments are limited by the psychoactive side-effects of CBI activation. Recently CBII has been described within the CNS, both in microglia and neuronal progenitor cells (NPCs), but with few exceptions, not by neurons within the CNS.

This has suggested that CBII agonists could have potential to treat various conditions without psycho-activity.

This article reviews the potential for CBII agonists as treatments for neurological conditions, with a focus on microglia and NPCs as drug targets. We first discuss the role of microglia in the healthy brain, and then the role of microglia in chronic neuroinflammatory disorders, including Alzheimer’s disease and Parkinson’s disease, as well as in neuroinflammation following acute brain injury such as stroke and global hypoxia. As activation of CBII receptor on microglia results in suppression of the proliferation and activation of microglia, there is potential for the anti-inflammatory properties of CBII agonist to treat neuropathologies that involve heightened microglia activity. In addition, activating CBII receptors may result in an increase in proliferation and affect migration of NPCs.Therefore, it is possible that CBII agonists may assist in the treatment of neuropathologies by increasing neurogenesis…”

http://www.ncbi.nlm.nih.gov/pubmed/20236042

The Cannabinoid CB2 Receptor as a Target for Inflammation-Dependent Neurodegeneration

“THE CANNABINOID CB2 RECEPTOR AS A BIORATIONAL TARGET FOR THE TREATMENT OF NEURODEGENERATION. The presence of CB2 receptors in microglia in the human Alzheimer’s diseased brain suggests that CB2 may provide a novel target for a range of neuropathologies.

 The first approved cannabinoid drugs were analogues of Δ9-tetrahydrocannabinol (Δ9-THC). Dronabinol is a natural isomer of THC that is found in the cannabis plant, and Marinol contains synthetic dronabinol. Marinol, and another analogue nabilone (Cesamet ) are used to prevent nausea and vomiting after treatment with anti-cancer medicines. More recently, GW-100 (Sativex) which combines nearly equal amounts of Δ9-THC and cannabidiol in a whole plant extract from cultivated cannabis, has been approved in Canada…

We conclude that the administration of CB2 agonists and antagonists may differentially alter microglia-dependent neuroinflammation. CB2 specific compounds have considerable therapeutic appeal over CB1 compounds, as the exclusive expression of CB2 on immune cells within the brain provides a highly specialised target, without the psychoactivity that plagues CB1 directed therapies.

In addition, CB2 activation appears to prevent or decrease microglial activation.

In a rodent model of Alzheimer’s disease microglial activation was completely prevented by administration of a selective CB2 agonist.”

http://www.ncbi.nlm.nih.gov/pubmed/18615177

Role of CB2 receptors in neuroprotective effects of cannabinoids.

“CB2 receptors, the so-called peripheral cannabinoid receptor type, were first described in the immune system, but they have been recently identified in the brain in healthy conditions and, in particular, after several types of cytotoxic stimuli. Specifically, CB2 receptors were identified in microglial cells, astrocytes and, to a lesser extent, in certain subpopulations of neurons.

Given the lack of psychoactivity demonstrated by selective CB2 receptor agonists, this receptor becomes an interesting target for the treatment of neurological diseases, in particular, the case of certain neurodegenerative disorders in which induction/up-regulation of CB2 receptors has been already demonstrated. These disorders include Alzheimer’s disease, Huntington’s chorea, amyotrophic lateral sclerosis and others. Interestingly, in experimental models of these disorders, the activation of CB2 receptors has been related to a delayed progression of neurodegenerative events, in particular, those related to the toxic influence of microglial cells on neuronal homeostasis.

 The present article will review the evidence supporting that CB2 receptors might represent a key element in the endogenous response against different types of cytotoxic events, and that this receptor type may be a clinically promising target for the control of brain damage in neurodegenerative disorders.”

 http://www.ncbi.nlm.nih.gov/pubmed/18291574