“Aberrant Notch signaling has recently emerged as a possible mechanism for the altered neurogenesis, cognitive impairment, and learning and memory deficits associated with Alzheimer disease (AD). Recently, targeting the endocannabinoid system in models of AD has emerged as a potential approach to slow the progression of the disease process. Although studies have identified neuroprotective roles for endocannabinoids, there is a paucity of information on modulation of the pro-survival Notch pathway by endocannabinoids. In this study the influence of the endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol, on the Notch-1 pathway and on its endogenous regulators were investigated in an in vitro model of AD. We report that AEA up-regulates Notch-1 signaling in cultured neurons… In summary, AEA has the proclivity to enhance Notch-1 signaling in an in vitro model of AD, which may have relevance for restoring neurogenesis and cognition in AD.”
Category Archives: Endocannabinoid System
Role of the endocannabinoid system in Alzheimer’s disease: new perspectives.
Abstract
“The role of the endocannabinoid system in several diseases is currently under intense study. Among these, Alzheimer’s disease may be a new promising area of research. We have recently reported the existence of profound changes in the location and density of several elements of this system in Alzheimer’s disease tissue samples, indicating that a non-neuronal endocannabinoid system is up-regulated in activated glia. Additional data from other groups suggest that glial cells may be important elements in the regulation of endocannabinoid system activity, both in health as in disease. Some of these aspects are briefly discussed in the present review.”
The therapeutic potential of the endocannabinoid system for Alzheimer’s disease.
“Based on the complex pathology of AD, a preventative, multimodal drug approach targeting a combination of pathological AD symptoms appears ideal. Importantly, cannabinoids show anti-inflammatory, neuroprotective and antioxidant properties and have immunosuppressive effects. Thus, the cannabinoid system should be a prime target for AD therapy. The cannabinoid receptor 2 appears to be a promising candidate but its role in AD has to be investigated cautiously. Furthermore, the phytocannabinoid cannabidiol is of particular interest as it lacks the psychoactive and cognition-impairing properties of other cannabinoids. In conclusion, future research should focus on the evaluation of the effects of manipulations to the endocannabinoid system in established animal models for AD, combined with early-phase studies in humans.”
Amyotrophic lateral sclerosis: delayed disease progression in mice by treatment with a cannabinoid.
Abstract
“Effective treatment for amyotrophic lateral sclerosis (ALS) remains elusive. Two of the primary hypotheses underlying motor neuron vulnerability are susceptibility to excitotoxicity and oxidative damage. There is rapidly emerging evidence that the cannabinoid receptor system has the potential to reduce both excitotoxic and oxidative cell damage. Here we report that treatment with Delta(9)-tetrahydrocannabinol (Delta(9)-THC) was effective if administered either before or after onset of signs in the ALS mouse model (hSOD(G93A) transgenic mice). Administration at the onset of tremors delayed motor impairment and prolonged survival in Delta(9)-THC treated mice when compared to vehicle controls. In addition, we present an improved method for the analysis of disease progression in the ALS mouse model. This logistic model provides an estimate of the age at which muscle endurance has declined by 50% with much greater accuracy than could be attained for any other measure of decline. In vitro, Delta(9)-THC was extremely effective at reducing oxidative damage in spinal cord cultures. Additionally, Delta(9)-THC is anti-excitotoxic in vitro. These cellular mechanisms may underlie the presumed neuroprotective effect in ALS. As Delta(9)-THC is well tolerated, it and other cannabinoids may prove to be novel therapeutic targets for the treatment of ALS.”
Increasing cannabinoid levels by pharmacological and genetic manipulation delay disease progression in SOD1 mice.
“Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the selective loss of motoneurons in the spinal cord, brain stem, and motor cortex. However, despite intensive research, an effective treatment for this disease remains elusive. In this study we show that treatment of postsymptomatic, 90-day-old SOD1G93A mice with a synthetic cannabinoid, WIN55,212-2, significantly delays disease progression…
Increasing evidence suggests that cannabinoids might have therapeutic potential in neurodegenerative conditions. In a variety of in vivo and in vitro models, cannabinoids exert neuroprotective effects under excitotoxic, ischemic, and inflammatory conditions. This combination of neuroprotective actions might be particularly relevant to ALS and suggests that cannabinoids might have a greater impact on disease progression than the established therapy that targets excitotoxicity alone.
… the neuroprotective effects observed following pharmacological and genetic augmentation of cannabinoid levels are not necessarily mediated by the CB1 receptor, and indeed inhibition of the CB1 receptor might actually be neuroprotective. Therefore, in contrast to previous studies that have suggested that cannabinoids exert neuroprotection via the CB1 receptor, the present results suggest that activation of CB2 receptors might underlie the beneficial effects of cannabinoids at least in SOD1G93A mice .”
Together these results show that cannabinoids have significant neuroprotective effects in this model of ALS and suggest that these beneficial effects may be mediated by non-CB1 receptor mechanisms.”
Endocannabinoids accumulate in spinal cord of SOD1 G93A transgenic mice.
Abstract
“Approximately 2% of amyotrophic lateral sclerosis (ALS) cases are caused by mutations in the super oxide dismutase 1 (SOD1) gene and transgenic mice for these mutations recapitulate many features of this devastating neurodegenerative disease. Here we show that the amount of anandamide (AEA) and 2-arachidonoylglycerol (2-AG), two endocannabinoids that have neuroprotective properties, increase in spinal cord of SOD1(G93A) transgenic mice. This increase occurs in the lumbar section of spinal cords, the first section to undergo neurodegeneration, and is significant before overt motor impairment. Our results show that chronic neurodegeneration induced by a genetic mutation increases endocannabinoid production possibly as part of an endogenous defense mechanism.”
The CB2 cannabinoid agonist AM-1241 prolongs survival in a transgenic mouse model of amyotrophic lateral sclerosis when initiated at symptom onset.
“Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive motor neuron loss, paralysis and death within 2-5 years of diagnosis. Currently, no effective pharmacological agents exist for the treatment of this devastating disease. Neuroinflammation may accelerate the progression of ALS. Cannabinoids produce anti-inflammatory actions via cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2), and delay the progression of neuroinflammatory diseases…
…treatment with non-selective cannabinoid partial agonists prior to, or upon, symptom appearance minimally delays disease onset and prolongs survival through undefined mechanisms…
…Δ9-Tetrahydrocannabinol (Δ9-THC) is the main psychoactive constituent in the plant Cannabis sativa (marijuana) and produces its effects by activation of cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2) cannabinoid receptors. CB1 receptors are expressed throughout the CNS, while CB2 receptors are expressed predominantly in immune cells and non-neuronal tissues. Therapeutic agents which modulate the cann-abinoid system are effective in treating a wide variety of disorders characterized by inflammation. More specifically, drugs which activate CB2 receptors successfully improve the symptoms of several inflammatory diseases…
More importantly, daily injections of the selective CB2 agonist AM-1241, initiated at symptom onset, increase the survival interval after disease onset by 56%. Therefore, CB2 agonists may slow motor neuron degeneration and preserve motor function, and represent a novel therapeutic modality for treatment of ALS.”
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2819701/
AM1241, a cannabinoid CB2 receptor selective compound, delays disease progression in a mouse model of amyotrophic lateral sclerosis.
“Effective treatment for amyotrophic lateral sclerosis (ALS) remains elusive. Motor neuron degeneration is the primary pathology in ALS; however non-neuronal cells contribute to the disease process. In particular, inflammatory processes have been shown to play an important role. AM1241 is a cannabinoid CB2 receptor selective agonist that has been shown to be effective in models of inflammation and hyperalgesia. Here we report that treatment with AM1241 was effective at slowing signs of disease progression when administered after onset of signs in an ALS mouse model (hSOD1(G93A) transgenic mice)…. As AM1241 was well tolerated by the animals, cannabinoid CB2 receptor-selective compounds may be the basis for developing new drugs for the treatment of ALS and other chronic neurodegenerative diseases.”
Abnormal sensitivity of cannabinoid CB1 receptors in the striatum of mice with experimental amyotrophic lateral sclerosis.
“Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that primarily affects motor neurons.
The sensitivity of cannabinoid CB1 receptors controlling both glutamate and GABA transmission was remarkably potentiated in ALS mice, indicating that adaptations of the endocannabinoid system might be involved in the pathophysiology of ALS. In conclusion, our data identify possible physiological correlates of striatal dysfunction in ALS mice, and suggest that cannabinoid CB1 receptors might be potential therapeutic targets for this dramatic disease.”
The endocannabinoid system in the inflammatory and neurodegenerative processes of multiple sclerosis and of amyotrophic lateral sclerosis.
Abstract
“Multiple sclerosis (MS) and amyotrophic lateral sclerosis (ALS) are chronic diseases of the central nervous system (CNS), featured by a complex interplay between inflammation and neurodegeneration. Increasing evidence supports the involvement of the endocannabinoid system (ECS) in both inflammatory and neurodegenerative processes typical of these pathological conditions. Exogenous or endogenous cannabinoids regulate the function of immune system by limiting immune response. On the other hand, by preventing excitotoxic damage, cannabinoids protect neuronal integrity and function. Of note, the ECS not only plays a role as modulator of disease processes, but it can also be disrupted by the same diseases. Agents modulating cannabinoid receptors or endocannabinoid tone provide promising therapeutic opportunities in the treatment of inflammatory neurodegenerative disorders of the CNS.”