Category Archives: Endocannabinoid System

The influence of cannabinoids on learning and memory processes of the dorsal striatum.

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“Extensive evidence indicates that the mammalian endocannabinoid system plays an integral role in learning and memory…

A tentative conclusion based on the available data is that acute disruption of the endocannabinoid system with either agonists or antagonists impairs, whereas chronic cannabinoid exposure enhances, dorsal striatum-dependent S-R/habit memory.

CB1 receptors are required for multiple forms of striatal synaptic plasticity implicated in memory, including short-term and long-term depression.

Interactions with the hippocampus-dependent memory system may also have a role in some of the observed effects of cannabinoids on habit memory.

The impairing effect often observed with acute cannabinoid administration argues for cannabinoid-based treatments for human psychopathologies associated with a dysfunctional habit memory system (e.g. post-traumatic stress disorder and drug addiction/relapse).”

http://www.ncbi.nlm.nih.gov/pubmed/26092091

Anandamide, Acting via CB2 Receptors, Alleviates LPS-Induced Neuroinflammation in Rat Primary Microglial Cultures.

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“Microglial activation is a polarized process divided into potentially neuroprotective phenotype M2 and neurotoxic phenotype M1, predominant during chronic neuroinflammation.

Endocannabinoid system provides an attractive target to control the balance between microglial phenotypes.

Anandamide as an immune modulator in the central nervous system acts via not only cannabinoid receptors (CB1 and CB2) but also other targets (e.g., GPR18/GPR55).

In summary, we showed that the endocannabinoid system plays a crucial role in the management of neuroinflammation by dampening the activation of an M1 phenotype. This effect was primarily controlled by the CB2 receptor, although functional cross talk with GPR18/GPR55 may occur.”

http://www.ncbi.nlm.nih.gov/pubmed/26090232

Endocannabinoids drive the acquisition of an alternative phenotype in microglia.

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“The ability of microglia to acquire diverse states of activation, or phenotypes, reflects different features that are determinant for their contribution to homeostasis in the adult CNS, and their activity in neuroinflammation, repair or immunomodulation.

Despite the widely reported immunomodulatory effects of cannabinoids in both the peripheral immune system and the CNS, less is known about how the endocannabinoid signaling system (eCBSS) influence the microglial phenotype.

The general aim of the present study was to investigate the role of endocannabinoids in microglia polarization by using microglia cell cultures.

We show that alternative microglia (M2a) and acquired deactivated microglia (M2c) exhibit changes in the eCB machinery that favor the selective synthesis of 2-AG and AEA, respectively.

Once released, these eCBs might be able to act through CB1 and/or CB2 receptors in order to influence the acquisition of an M2 phenotype.

We present three lines of evidence that the eCBSS is critical for the acquisition of the M2 phenotype: (i) M2 polarization occurs on exposure to the two main endocannabinoids 2-AG and AEA in microglia cultures; (ii)cannabinoid receptor antagonists block M2 polarization; and, (iii) M2 polarization is dampened in microglia from CB2 receptor knockout mice.

Taken together, these results indicate the interest of eCBSS for the regulation of microglial activation in normal and pathological conditions.”

http://www.ncbi.nlm.nih.gov/pubmed/26086345

Coadministration of indomethacin and minocycline attenuates established paclitaxel-induced neuropathic thermal hyperalgesia: Involvement of cannabinoid CB1 receptors.

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“Taxanes such as paclitaxel, which are chemotherapeutic drugs, cause dose-dependent painful neuropathy in some patients.

We investigated whether coadministration of minocycline and indomethacin produces antinociceptive effects in mice with paclitaxel-induced neuropathic thermal hyperalgesia and if the cannabinoid system is involved…

In conclusion our results indicate that coadministration of minocycline and indomethacin abrogates established paclitaxel-induced neuropathic thermal hyperalgesia in mice, and the potentiation of the antinociceptive effects of this combination involves the cannabinoid system.”

Role of the Endocannabinoid System in Diabetes and Diabetic Complications.

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“Increasing evidence suggests that an overactive endocannabinoid system (ECS) may contribute to the development of diabetes by promoting energy intake and storage, impairing both glucose and lipid metabolism, and by exerting pro-apoptotic effects in pancreatic β cells, and by facilitating inflammation in pancreatic islets.

Furthermore, hyperglycemia associated with diabetes has also been implicated in triggering perturbations of the ECS amplifying the above mentioned pathological processes, eventually culminating in a vicious circle.

Compelling evidence from preclinical studies indicates that the ECS also influences diabetes-induced oxidative stress, inflammation, fibrosis, and subsequent tissue injury in target organs for diabetic complications.

In this review, we provide an update on the contribution of the ECS to the pathogenesis of diabetes and diabetic microvascular (retinopathy, nephropathy, and neuropathy) and cardiovascular complications. The therapeutic potential of targeting the ECS is also discussed.”

http://www.ncbi.nlm.nih.gov/pubmed/26076890#

http://www.thctotalhealthcare.com/category/diabetes/

Neurobiological Interactions Between Stress and the Endocannabinoid System.

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“Stress affects a constellation of physiological systems in the body and evokes a rapid shift in many neurobehavioral processes.

A growing body of work indicates that the endocannabinoid (eCB) system is an integral regulator of the stress response.

In the current review, we discuss the evidence to date that demonstrates stress-induced regulation of eCB signaling and the consequential role changes in eCB signaling play with respect to many of the effects of stress.

Across a wide array of stress paradigms, studies have generally shown that stress evokes bidirectional changes in the two eCB molecules, anandamide (AEA) and 2-arachidonoyl glycerol (2-AG), with stress exposure reducing AEA levels and increasing 2-AG levels.

Additionally, in almost every brain region examined, exposure to chronic stress reliably causes a down-regulation or loss of cannabinoid type 1 (CB1) receptors.

With respect to the functional role of changes in eCB signaling during stress, studies have demonstrated that the decline in AEA appears to contribute to the manifestation of the stress response, including activation of the hypothalamic-pituitary-adrenal (HPA) axis and increases in anxiety behavior, while the increased 2-AG signaling contributes to termination and adaptation of the HPA axis, as well as potentially contributing to changes in pain perception and synaptic plasticity.

More so, translational studies have shown that eCB signaling in humans regulates many of the same domains and appears to be a critical component of stress regulation, and impairments in this system may be involved in the vulnerability to stress-related psychiatric conditions, such as depression and post-traumatic stress disorder.

Collectively, these data create a compelling argument that eCB signaling is an important regulatory system in the brain that largely functions to buffer against many of the effects of stress and that dynamic changes in this system contribute to different aspects of the stress response.”

http://www.ncbi.nlm.nih.gov/pubmed/26068727

Intrathecal cannabinoid-1 receptor agonist prevents referred hyperalgesia in acute acrolein-induced cystitis in rats.

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“We investigated the capacity of intrathecal arachidonyl-2′-chloroethylamide (ACEA), a cannabinoid-1 receptor (CB1R) agonist, to inhibit referred hyperalgesia and increased bladder contractility resulting from acute acrolein-induced cystitis in rats…

These findings suggest that pain arising from cystitis may be inhibited by activation of spinal CB1R but the acute local response of the bladder appeared to be unaffected by stimulation of spinal CB1R.”

http://www.ncbi.nlm.nih.gov/pubmed/26069885

In vivo inflammation imaging using a CB2R-targeted near infrared fluorescent probe.

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“Chronic inflammation is considered as a critical cause of a host of disorders, such as cancer, rheumatoid arthritis, atherosclerosis, and neurodegenerative diseases…

Imaging tools that can specifically target inflammation are therefore important to help reveal the role of inflammation in disease progression, and allows for developing new therapeutic strategies to ultimately improve patient care.

The purpose of this study was to develop a new in vivo inflammation imaging approach by targeting the cannabinoid receptor type 2 (CB2R), an emerging inflammation biomarker, using a unique near infrared (NIR) fluorescent probe…

The combined evidence indicates that NIR760-mbc94 is a promising inflammation imaging probe. Moreover, in vivo CB2R-targeted fluorescence imaging may have potential in the study of inflammation-related diseases.”

http://www.ncbi.nlm.nih.gov/pubmed/26069858

Does cannabis affect dopaminergic signaling in the human brain? A systematic review of evidence to date.

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“While abnormalities in multiple pathways may lead to schizophrenia, an abnormality in dopamine neurotransmission is considered to be the final common abnormality.

One would thus expect cannabis use to be associated with dopamine signaling alterations.

This is the first systematic review of all studies, both observational as well as experimental, examining the acute as well as chronic effect of cannabis or its main psychoactive ingredient, THC, on the dopamine system in man…

In man, there is as yet little direct evidence to suggest that cannabis use affects acute striatal dopamine release or affects chronic dopamine receptor status in healthy human volunteers. ”

http://www.ncbi.nlm.nih.gov/pubmed/26068702

Role of the endocannabinoid system in the emotional manifestations of osteoarthritis pain.

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“The levels of the endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol.

In this study, we investigated the role of the endocannabinoid system (ECS) in the emotional and cognitive alterations associated with osteoarthritis pain.

Changes found in these biomarkers of the ECS correlated with pain, affective and cognitive symptoms in these patients.

The ECS plays a crucial role in osteoarthritis and represents an interesting pharmacological target and biomarker of this disease.”

http://www.ncbi.nlm.nih.gov/pubmed/26067584

http://www.thctotalhealthcare.com/category/osteoarthritis/