Category Archives: Depression

Brain CB₂ Receptors: Implications for Neuropsychiatric Disorders.

Posted on by
Reply

pharmaceuticals-logo

“Although previously thought of as the peripheral cannabinoid receptor, it is now accepted that the CB₂ receptor is expressed in the central nervous system on microglia, astrocytes and subpopulations of neurons.

Expression of the CB₂ receptor in the brain is significantly lower than that of the CB₁ receptor. Conflicting findings have been reported on the neurological effects of pharmacological agents targeting the CB₂ receptor under normal conditions.

Under inflammatory conditions, CB₂ receptor expression in the brain is enhanced and CB2 receptor agonists exhibit potent anti-inflammatory effects. These findings have prompted research into the CB₂ receptor as a possible target for the treatment of neuroinflammatory and neurodegenerative disorders.

Neuroinflammatory alterations are also associated with neuropsychiatric disorders and polymorphisms in the CB₂ gene have been reported in depression, eating disorders and schizophrenia. This review will examine the evidence to date for a role of brain CB₂ receptors in neuropsychiatric disorders.”

 https://www.ncbi.nlm.nih.gov/pubmed/27713365

Endocannabinoid signaling in social functioning: an RDoC perspective.

Posted on by
Reply

Image result for Transl Psychiatry.

“Core deficits in social functioning are associated with various neuropsychiatric and neurodevelopmental disorders, yet biomarker identification and the development of effective pharmacological interventions has been limited.

Recent data suggest the intriguing possibility that endogenous cannabinoids, a class of lipid neuromodulators generally implicated in the regulation of neurotransmitter release, may contribute to species-typical social functioning.

Systematic study of the endogenous cannabinoid signaling could, therefore, yield novel approaches to understand the neurobiological underpinnings of atypical social functioning.

This article provides a critical review of the major components of the endogenous cannabinoid system (for example, primary receptors and effectors-Δ9-tetrahydrocannabinol, cannabidiol, anandamide and 2-arachidonoylglycerol) and the contributions of cannabinoid signaling to social functioning.

Data are evaluated in the context of Research Domain Criteria constructs (for example, anxiety, chronic stress, reward learning, motivation, declarative and working memory, affiliation and attachment, and social communication) to enable interrogation of endogenous cannabinoid signaling in social functioning across diagnostic categories.

The empirical evidence reviewed strongly supports the role for dysregulated cannabinoid signaling in the pathophysiology of social functioning deficits observed in brain disorders, such as autism spectrum disorder, schizophrenia, major depressive disorder, posttraumatic stress disorder and bipolar disorder.

Moreover, these findings indicate that the endogenous cannabinoid system holds exceptional promise as a biological marker of, and potential treatment target for, neuropsychiatric and neurodevelopmental disorders characterized by impairments in social functioning.”

https://www.ncbi.nlm.nih.gov/pubmed/27676446

Don’t Worry, Be Happy: Endocannabinoids and Cannabis at the Intersection of Stress and Reward.

Posted on by
Reply

Image result for annual review of pharmacology and toxicology

“Cannabis enables and enhances the subjective sense of well-being by stimulating the endocannabinoid system (ECS), which plays a key role in modulating the response to stress, reward, and their interactions.

The recent shift toward legalization of medical or recreational cannabis has renewed interest in investigating the physiological role of the ECS as well as the potential health effects, both adverse and beneficial, of cannabis.

Here we review our current understanding of the ECS and its complex physiological roles.

We discuss the implications of this understanding vis-á-vis the ECS’s modulation of stress and reward and its relevance to mental disorders in which these processes are disrupted (i.e., addiction, depression, posttraumatic stress disorder, schizophrenia), along with the therapeutic potential of strategies to manipulate the ECS for these conditions.”

http://www.ncbi.nlm.nih.gov/pubmed/27618739

Interaction between interleukin-1β and type-1 cannabinoid receptor is involved in anxiety-like behavior in experimental autoimmune encephalomyelitis.

Posted on by
Reply

Image result for J Neuroinflammation.

“Mood disorders, including anxiety and depression, are frequently diagnosed in multiple sclerosis (MS) patients, even independently of the disabling symptoms associated with the disease.

Anatomical, biochemical, and pharmacological evidence indicates that type-1 cannabinoid receptor (CB1R) is implicated in the control of emotional behavior and is modulated during inflammatory neurodegenerative diseases such as MS and experimental autoimmune encephalomyelitis (EAE).

We investigated whether CB1R could exert a role in anxiety-like behavior in mice with EAE. We performed behavioral, pharmacological, and electrophysiological experiments to explore the link between central inflammation, mood, and CB1R function in EAE.

Overall, results of the present investigation indicate that synaptic dysfunction linked to CB1R is involved in EAE-related anxiety and motivation-based behavior and contribute to clarify the complex neurobiological mechanisms underlying mood disorders associated to MS.

Collectively, our data contribute to clarify the synaptic and, at least in part, molecular basis of mood disturbances in EAE and, possibly, MS. Understanding the neurobiological underpinning of anxiety-like behavior in EAE mice is of crucial importance to optimize the treatment of mood disturbance in MS and, possibly, other neuroinflammatory diseases.

In this direction, targeting the endocannabinoid system may be a valid therapeutic tool for the treatment of both psychiatric and motor symptoms in MS patients.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5009553/

Anandamide reverses depressive-like behavior, neurochemical abnormalities and oxidative-stress parameters in streptozotocin-diabetic rats: Role of CB1 receptors.

Posted on by
Reply

“The pathophysiology associated with increased prevalence of depression in diabetics is not completely understood, although studies have pointed the endocannabinoid system as a possible target. Then, we aimed to investigate the role of this system in the pathophysiology of depression associated with diabetes.

Together, our data suggest that in depression associated with diabetes, the endocannabinoid anandamide has a potential to induce neuroadaptative changes able to improve the depressive-like response by its action as a CB1 receptor agonist.”

http://www.ncbi.nlm.nih.gov/pubmed/27544303

Decreased depression in marijuana users.

Posted on by
Reply

“Over 4400 adult internet users completed The Center for Epidemiologic Studies Depression scale and measures of marijuana use.

We employed an internet survey in an effort to recruit the most depressed and marijuana-involved participants, including those who might prove unwilling to travel to the laboratory or discuss drug use on the phone or in person.

We compared those who consumed marijuana daily, once a week or less, or never in their lives.

Despite comparable ranges of scores on all depression subscales, those who used once per week or less had less depressed mood, more positive affect, and fewer somatic complaints than non-users.

Daily users reported less depressed mood and more positive affect than non-users.

These data suggest that adults apparently do not increase their risk for depression by using marijuana.”

http://www.ncbi.nlm.nih.gov/pubmed/15964704

Endocannabinoid system: Role in depression, reward and pain control (Review).

Posted on by
Reply

 

“Depression and pain co-exist in almost 80% of patients and are associated with impaired health-related quality of life, often contributing to high mortality. However, the majority of patients who suffer from the comorbid depression and pain are not responsive to pharmacological treatments that address either pain or depression, making this comorbidity disorder a heavy burden on patients and society.

In ancient times, this depression-pain comorbidity was treated using extracts of the Cannabis sativa plant, known now as marijuana and the mode of action of Δ9‑tetrahydrocannabinol, the active cannabinoid ingredient of marijuana, has only recently become known, with the identification of cannabinoidreceptor type 1 (CB1) and CB2.

Subsequent investigations led to the identification of endocannabinoids, anandamide and 2-arachidonoylglycerol, which exert cannabinomimetic effects through the CB1 and CB2 receptors, which are located on presynaptic membranes in the central nervous system and in peripheral tissues, respectively.

These endocannabinoids are produced from membrane lipids and are lipohilic molecules that are synthesized on demand and are eliminated rapidly after their usage by hydrolyzing enzymes.

Clinical studies revealed altered endocannabinoid signaling in patients with chronic pain.

Considerable evidence suggested the involvement of the endocannabinoid system in eliciting potent effects on neurotransmission, neuroendocrine, and inflammatory processes, which are known to be deranged in depression and chronic pain.

Several synthetic cannabinomimetic drugs are being developed to treat pain and depression. However, the precise mode of action of endocannabinoids on different targets in the body and whether their effects on pain and depression follow the same or different pathways, remains to be determined.”

http://www.ncbi.nlm.nih.gov/pubmed/27484193

Cannabinoids biology: the search for new therapeutic targets.

Posted on by
Reply

“Cannabinoids, in the form of marijuana plant extracts, have been used for thousands of years for a wide variety of medical conditions, ranging from general malaise and mood disorders to more specific ailments, such as pain, nausea, and muscle spasms.

The discovery of tetrahydrocannabinol, the active principal in marijuana, and the identification and cloning of two cannabinoid receptors (i.e., CB1 and CB2) has subsequently led to biomedical appreciation for a family of endocannabinoid lipid transmitters.

The biosynthesis and catabolism of the endocannabinoids and growing knowledge of their broad physiological roles are providing insight into potentially novel therapeutic targets.

Compounds directed at one or more of these targets may allow for cannabinoid-based therapeutics with limited side effects and abuse liability.”

http://www.ncbi.nlm.nih.gov/pubmed/16809476

New Study Finds Marijuana To Be Effective Against Depression, Migraine and Anxiety

Posted on by
Reply

“Research has suggested that cannabis may be a promising treatment option for a number of different physical and mental health conditions, from post-traumatic stress disorder to chronic pain. A study released this week suggests that depression , anxiety and migraine can be added to that list.

Neuroscientists from the University of Buffalo’s Research Institute on Addictions found that endocannabinoids — chemical compounds in the brain that activate the same receptors as THC, an active compound in marijuana — may be helpful in treating depression, anxiety and migraine that results from chronic stress.

In studies on rats, the researchers found that chronic stress reduced the production of endocannabinoids, which affect our cognition, emotion and behavior, and have been linked to reduced feelings of pain and anxiety, increases in appetite and overall feelings of well-being. The body naturally produces these compounds, which are similar to the chemicals in cannabis. Reduction of endocannabinoid production may be one reason that chronic stress is a major risk factor in the development of depression.

Then, the research team administered marijuana cannabinoids to the rats, finding it to be an effective way to restore endocannabinoid levels in their brains — possibly, thereby, alleviating some symptoms of depression.

“Using compounds derived from cannabis — marijuana — to restore normal endocannabinoid function could potentially help stabilize moods and ease depression,” lead researcher Dr. Samir Haj-Dahmane said in a university press release.

Recent research around marijuana’s effect on symptoms of post-traumatic stress disorder further bolsters the Buffalo neuroscientists’ findings, since both disorders involve the way the brain responds to stress. A study published last year in the journal Neuropsychopharmacology, for instance, found synthetic cannabinoids triggered changes in brain centers associated with traumatic memories in rats, preventing some of the behavioral and physiological symptoms of PTSD. Another study published last year found that patients who smoked cannabis experienced a 75 percent reduction in PTSD symptoms.

However, it’s important to note that the relationship between marijuana and depression  is complex. Some research has suggested that regular and heavy marijuana smokers are at a higher risk for depression, although a causal link between cannabis use and depression has not been established. More studies are needed in order to determine whether, and how, marijuana might be used in a clinical context for patients with depression.”  http://painphysicianjournal.co/2016/06/30/new-study-finds-marijuana-to-be-effective-against-depression-migraine-and-anxiety/

New Study Finds Marijuana To Be Effective Against Depression, Migraine and Anxiety

Fluorinated Cannabidiol Derivatives: Enhancement of Activity in Mice Models Predictive of Anxiolytic, Antidepressant and Antipsychotic Effects.

Posted on by
Reply

“Cannabidiol (CBD) is a major Cannabis sativa constituent, which does not cause the typical marijuana psychoactivity. However, it has been shown to be active in a numerous pharmacological assays, including mice tests for anxiety, obsessive-compulsive disorder, depression and schizophrenia. In human trials the doses of CBD needed to achieve effects in anxiety and schizophrenia are high. We report now the synthesis of 3 fluorinated CBD derivatives, one of which, 4′-F-CBD (HUF-101) (1), is considerably more potent than CBD in behavioral assays in mice predictive of anxiolytic, antidepressant, antipsychotic and anti-compulsive activity. Similar to CBD, the anti-compulsive effects of HUF-101 depend on cannabinoid receptors.”

http://www.ncbi.nlm.nih.gov/pubmed/27416026