Role of cannabinoid receptor type 1 in rostral ventrolateral medulla in high-fat diet-induced hypertension in rats.

Posted on March 3, 2018 by David

Image result for ovid journal

“Stimulation of cannabinoid type 1 (CB1) receptor in the rostral ventrolateral medulla (RVLM) increases renal sympathetic activity (RSNA) and blood pressure (BP) in rats. Thus, we hypothesized that CB1 receptor in the RVLM may play a critical role in the development of obesity-induced hypertension.

METHODS:

To this end, we evaluated the levels of endocannabinoids and CB1 receptors in the RVLM in high-fat diet (HFD)-induced hypertensive rats. We then used pharmacological and molecular methods to examine the role of RVLM CB1 receptors in regulation of BP, heart rate (HR), and RSNA in obesity-induced hypertensive rats.

RESULTS:

We found that HFD-fed rats exhibited higher basal BP, HR, and RSNA than standard diet-fed rats, which were associated with increased levels of endocannabinoids and CB1 receptor expression in the RVLM. Furthermore, unilateral intra-RVLM microinjections of AM251 (0, 100, or 500 nM/0.5 μl/site) dose-dependently decreased BP, HR, and RSNA to a greater extent in HFD-fed rats than in standard diet-fed rats. Finally, siRNA-mediated knockdown of CB1 receptor expression in the RVLM robustly decreased BP, HR, and RSNA in HFD-fed rats.

CONCLUSION:

Taken together, our results suggested that enhanced CB1 receptor-mediated neurotransmissions in the RVLM may play a role in the development of obesity-induced hypertension.”

https://www.ncbi.nlm.nih.gov/pubmed/29493561

https://insights.ovid.com/crossref?an=00004872-201804000-00015

The Role of Cannabinoid Receptor 1 in the Immunopathology of Respiratory Syncytial Virus.

Posted on February 21, 2018 by David

Mary Ann Liebert, Inc. publishers

“Endocannabinoid system plays an important role in pathophysiologic processes such as immune functions and impacts on disease severity.

Our previous study showed that cannabinoid receptor 2 (CB2) affects clinical course of respiratory syncytial virus (RSV) infection. In this study, we investigated the role of cannabinoid receptor 1 (CB1) in RSV immunopathology and its therapeutic potential in mice model.

This study and our previous finding indicated that endocannabinoid signaling regulates the inflammatory response to RSV infection, and is a potential therapeutic candidate for alleviation of RSV-associated immunopathology.”

https://www.ncbi.nlm.nih.gov/pubmed/29461930

http://online.liebertpub.com/doi/10.1089/vim.2017.0098

Sex differences in antinociceptive response to Δ-9-tetrahydrocannabinol and CP 55,940 in the mouse formalin test.

Posted on February 21, 2018 by David

“Cannabinoids have shown promise for the treatment of intractable pain states and may represent an alternative pharmacotherapy for pain management.

A growing body of clinical evidence suggests a role for sex in pain perception and in cannabinoid response.

We examined cannabinoid sensitivity and tolerance in male and female mice expressing a desensitization-resistant form (S426A/S430A) of the cannabinoid type 1 receptor (CB1R).

Mice were assessed for acute and inflammatory nociceptive behaviors in the formalin test following pretreatment with either vehicle or mixed CB1R/CB2R agonists, Δ-9-tetrahydrocannabinol ([INCREMENT]-THC) (1-6 mg/kg) or CP 55,940 (0.06-0.2 mg/kg). Tolerance to the effects of 6 mg/kg [INCREMENT]-THC or 0.1 mg/kg CP 55,940 was examined by the formalin test following chronic daily dosing.

Female mice showed decreased sensitivity to the effects of [INCREMENT]-THC and CP 55,940 compared with male mice. The S426A/S430A mutation increased the attenuation of nociceptive behaviors for both agonists in both sexes. Female mice displayed delayed tolerance to [INCREMENT]-THC compared with male mice, whereas the S426A/S430A mutation conferred a delay in tolerance to [INCREMENT]-THC in both sexes. Male S426A/S430A mutant mice also display resistance to tolerance to CP 55,940 compared with wild-type controls.

This study demonstrates sex and genotype differences in response for two different cannabinoid agonists. The results underscore the importance of including both male and female mice in preclinical studies of pain and cannabinoid pharmacology.”

https://www.ncbi.nlm.nih.gov/pubmed/29461336

https://insights.ovid.com/crossref?an=00001756-900000000-98413

Limited Access to a High Fat Diet Alters Endocannabinoid Tone in Female Rats.

Posted on February 20, 2018 by David

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“Emerging evidence suggest an impaired endocannabinoid activity in the pathophysiology of binge eating disorder (BED). Herein, we investigated whether endocannabinoid tone could be modified as a consequence of dietary-induced binge eating in female rats.

For this purpose, brain levels of the endocannabinoids anandamide (AEA) and 2-arachidonoyl glycerol (2-AG), as well as two endocannabinoid-like lipids, oleoylethanolamide (OEA) and palmitoylethanolamide (PEA), were assessed in different brain areas involved in the hedonic feeding (i.e., prefrontal cortex, nucleus accumbens, amygdala, hippocampus, and hypothalamus).

The brain density of cannabinoid type-1 receptors (CB₁) was also evaluated. Furthermore, we determined plasma levels of leptin, ghrelin, and corticosterone hormones, which are well-known to control the levels of endocannabioids and/or CB1 receptors in the brain.

To induce binge eating behavior, rats were subject to an intermittent and limited access to a high fat diet (HFD) (margarine). Three experimental groups were used, all with ad libitum access to chow: control (CTRL), with no access to margarine; low restriction (LR), with 2 h margarine access 7 days/week; high restriction (HR), with 2 h margarine access 3 days/week. Bingeing was established when margarine intake in the HR group exceeded that of the LR group.

Our results show that, compared to CTRL, AEA significantly decreased in the caudate putamen, amygdala, and hippocampus of HR group. In contrast, 2-AG significantly increased in the hippocampus while OEA decreased in the hypothalamus. Similar to the HR group, AEA and OEA decreased respectively in the amygdala and hypothalamus and 2-AG increased in the hippocampus of LR group. Moreover, LR group also had AEA decreased in the prefrontal cortex and increased in the nucleus accumbens. In both groups we found the same reduction of CB₁ receptor density in the prefrontal cortex compared to CTRL. Also, LR and HR groups showed alterations in both ghrelin and corticosterone levels, while leptin remained unaltered.

In conclusion, our findings show a modified endocannabinoid tone due to margarine exposure, in several brain areas that are known to influence the hedonic aspect of food. Even if not uniquely specific to binge eating, margarine-induced changes in endocannabinoid tone could contributes to the development and maintenance of this behavior.”

https://www.ncbi.nlm.nih.gov/pubmed/29456490

https://www.frontiersin.org/articles/10.3389/fnins.2018.00040/full

Role of the Endocannabinoid System in the Neurobiology of Suicide

Posted on February 19, 2018 by David

Cover of The Neurobiological Basis of Suicide

“In the past decade, remarkable advances have been made in cannabinoid (CB) research. The brain endocannabinoid (eCB) system modulates several neurobiological processes and its dysfunction is suggested to be involved in the pathophysiology of mood and drug use disorders.

The CB1 receptor–mediated signaling, in particular, has been shown to play a critical role in the neural circuitry that mediates mood, motivation, and emotional behaviors. This chapter presents the data pertaining to the involvement of the eCB system in depression, suicide, and alcohol addiction.

It appears that the eCB system might have a critical role in the regulation of mood and emotional responses that are impaired in patients with depression and suicidal behavior.

The data provided in this chapter support the notion that the eCB system might be an additional target for the development of a drug against alcohol use, depression, and suicidal behavior.

Among therapeutic agents, antidepressants are the most widely used drugs for the treatment of depression-related disorders.”

https://www.ncbi.nlm.nih.gov/pubmed/23035286

https://www.ncbi.nlm.nih.gov/books/NBK107200/

“Antidepressant-like effect of Δ9-tetrahydrocannabinol and other cannabinoids isolated from cannabis sativa L. The antidepressant action of cannabis as well as the interaction between antidepressants and the endocannabinoid system has been reported. Results of this study show that Δ9-THC and other cannabinoids exert anti-depressant-like actions, and thus may contribute to the overall mood-elevating properties of cannabis.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2866040/

Long-term depression induced by endogenous cannabinoids produces neuroprotection via astroglial CB1R after stroke in rodents.

Posted on February 14, 2018 by David

“Ischemia not only activates cell death pathways but also triggers endogenous protective mechanisms. However, it is largely unknown what is the essence of the endogenous neuroprotective mechanisms induced by preconditioning. In this study we demonstrated that systemic injection of JZL195, a selective inhibitor of eCB clearance enzymes, induces in vivo long-term depression at CA3-CA1 synapses and at PrL-NAc synapses produces neuroprotection. JZL195-elicited long-term depression is blocked by AM281, the antagonist of cannabinoid 1 receptor (CB₁R) and is abolished in mice lacking cannabinoid CB₁ receptor (CB₁R) in astroglial cells, but is conserved in mice lacking CB₁R in glutamatergic or GABAergic neurons. Blocking the glutamate NMDA receptor and the synaptic trafficking of glutamate AMPA receptor abolishes both long-term depression and neuroprotection induced by JZL195. Mice lacking CB₁R in astroglia show decreased neuronal death following cerebral ischemia. Thus, an acute elevation of extracellular eCB following eCB clearance inhibition results in neuroprotection through long-term depression induction after sequential activation of astroglial CB₁R and postsynaptic glutamate receptors.”

https://www.ncbi.nlm.nih.gov/pubmed/29432698

http://journals.sagepub.com/doi/abs/10.1177/0271678X18755661?journalCode=jcba

Blockade of cannabinoid 1 receptor improves glucose responsiveness in pancreatic beta cells.

Posted on February 14, 2018 by David

Journal of Cellular and Molecular Medicine

“Cannabinoid 1 receptors (CB1Rs) are expressed in peripheral tissues, including islets of Langerhans, where their function(s) is under scrutiny. Using mouse β-cell lines, human islets and CB1R-null (CB1R^-/- ) mice, we have now investigated the role of CB1Rs in modulating β-cell function and glucose responsiveness. Synthetic CB1R agonists diminished GLP-1-mediated cAMP accumulation and insulin secretion as well as glucose-stimulated insulin secretion in mouse β-cell lines and human islets. In addition, silencing CB1R in mouse β cells resulted in an increased expression of pro-insulin, glucokinase (GCK) and glucose transporter 2 (GLUT2), but this increase was lost in β cells lacking insulin receptor. Furthermore, CB1R^-/- mice had increased pro-insulin, GCK and GLUT2 expression in β cells. Our results suggest that CB1R signalling in pancreatic islets may be harnessed to improve β-cell glucose responsiveness and preserve their function. Thus, our findings further support that blocking peripheral CB1Rs would be beneficial to β-cell function in type 2 diabetes.”

https://www.ncbi.nlm.nih.gov/pubmed/29431265

http://onlinelibrary.wiley.com/doi/10.1111/jcmm.13523/abstract

Role for neuronal nitric-oxide synthase in cannabinoid-induced neurogenesis.

Posted on February 12, 2018 by David

Role for neuronal nitric-oxide synthase in cannabinoid-induced neurogenesis. “Cannabinoids, acting through the CB1 cannabinoid receptor (CB1R), protect the brain against ischemia and related forms of injury.

This may involve inhibiting the neurotoxicity of endogenous excitatory amino acids and downstream effectors, such as nitric oxide (NO).

Cannabinoids also stimulate neurogenesis in the adult brain through activation of CB1R.

Because NO has been implicated in neurogenesis, we investigated whether cannabinoid-induced neurogenesis, like cannabinoid neuroprotection, might be mediated through alterations in NO production.” https://aggregator.leafscience.org/role-for-neuronal-nitric-oxide-synthase-in-cannabinoid-induced-neurogenesis/

“Nitric oxide negatively regulates mammalian adult neurogenesis.” http://www.pnas.org/content/100/16/9566.long

“Thus, cannabinoids appear to stimulate adult neurogenesis by opposing the antineurogenic effect of NO.” http://jpet.aspetjournals.org/content/jpet/319/1/150.full.pdf

Acute ethanol inhibition of adult hippocampal neurogenesis involves CB1 cannabinoid receptor signaling.

Posted on February 10, 2018 by David

Alcoholism: Clinical and Experimental Research

“Chronic ethanol exposure has been found to inhibit adult hippocampal neurogenesis in multiple models of alcohol addiction. Together, these findings suggest that acute CB1R cannabinoid receptor activation and binge ethanol treatment reduce neurogenesis through mechanisms involving CB1R. ” https://www.ncbi.nlm.nih.gov/pubmed/29417597 http://onlinelibrary.wiley.com/doi/10.1111/acer.13608/abstract

“Alcohol-induced neurodegeneration” http://www.diva-portal.org/smash/record.jsf?pid=diva2%3A666727&dswid=174

“Defective Adult Neurogenesis in CB1 Cannabinoid Receptor Knockout Mice. Pharmacological studies suggest a role for CB1 cannabinoid receptors (CB1R) in regulating neurogenesis in the adult brain.” http://molpharm.aspetjournals.org/content/66/2/204.full

“Activation of Type 1 Cannabinoid Receptor (CB1R) Promotes Neurogenesis in Murine Subventricular Zone Cell Cultures” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3660454/

“Several studies and patents suggest that the endocannabinoid system has neuro-protective properties and might be a target in neurodegenerative diseases” https://www.ncbi.nlm.nih.gov/pubmed/27364363

“The endocannabinoid system and neurogenesis in health and disease.” https://www.ncbi.nlm.nih.gov/pubmed/17404371

“The role of cannabinoids in adult neurogenesis. Pharmacological targeting of the cannabinoid system as a regulator of neurogenesis may prove a fruitful strategy in the prevention or treatment of mood or memory disorders.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4543605/

“Regulation of Adult Neurogenesis by Cannabinoids” https://www.researchgate.net/publication/264424221_Regulation_of_Adult_Neurogenesis_by_Cannabinoids

“Delta-9-Tetrahydrocannabinol (∆9-THC) Induce Neurogenesis and Improve Cognitive Performances of Male Sprague Dawley Rats. Administration of ∆⁹-THC was observed to enhance the neurogenesis in the brain, especially in hippocampus thus improved the cognitive function of rats.” https://www.ncbi.nlm.nih.gov/pubmed/28933048

“Cannabidiol Reduces Aβ-Induced Neuroinflammation and Promotes Hippocampal Neurogenesis through PPARγ Involvement. CBD was observed to stimulate hippocampal neurogenesis.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3230631/

“Cannabinoids promote embryonic and adult hippocampus neurogenesis and produce anxiolytic- and antidepressant-like effects. Chronic administration of the major drugs of abuse including opiates, alcohol, nicotine, and cocaine has been reported to suppress hippocampal neurogenesis in adult rats. Plant-derived, or synthetic cannabinoids may promote hippocampal neurogenesis. Cannabinoids appear to be the only illicit drug whose capacity to produce increased hippocampal newborn neurons is positively correlated with its anxiolytic- and antidepressant-like effects. In summary, since adult hippocampal neurogenesis is suppressed following chronic administration of opiates, alcohol, nicotine, and cocaine, the present study suggests that cannabinoids are the only illicit drug that can promote adult hippocampal neurogenesis following chronic administration.” https://www.jci.org/articles/view/25509

Involvement of spinal cannabinoid receptors in the antipruritic effects of WIN 55,212-2, a cannabinoid receptor agonist.

Posted on February 10, 2018 by David

Clinical and Experimental Dermatology

“Cannabinoids have been used for their analgesic and euphoric effects for millennia, but recently the antipruritic effects of cannabis have been discovered.

Considering the similarities between pain and itch sensations, we hypothesized that cannabinoid receptors may play a role in the antipruritic effects of cannabinoids.

Our findings support prior researches indicating that cannabinoids exert antipruritic effects. Moreover, our results show that the antipruritic effects of cannabinoids are partially mediated by spinal CB1 receptors.”

https://www.ncbi.nlm.nih.gov/pubmed/29424035

http://onlinelibrary.wiley.com/doi/10.1111/ced.13398/abstract

www.thctotalhealthcare.com

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