Tag Archives: cannabinoid

Cannabidiol reduces host immune response and prevents cognitive impairments in Wistar rats submitted to pneumococcal meningitis.

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 European Journal of Pharmacology “Pneumococcal meningitis is a life-threatening disease characterized by an acute infection affecting the pia matter, arachnoid and subarachnoid space. The intense inflammatory response is associated with a significant mortality rate and neurologic sequelae, such as, seizures, sensory-motor deficits and impairment of learning and memory.

The aim of this study was to evaluate the effects of acute and extended administration of cannabidiol on pro-inflammatory cytokines and behavioral parameters in adult Wistar rats submitted to pneumococcal meningitis.

The extended administration of cannabidiol at different doses reduced the TNF-α level in frontal cortex. Prolonged treatment with canabidiol, 10mg/kg, prevented memory impairment in rats with pneumococcal meningitis.

Although descriptive, our results demonstrate that cannabidiol has anti-inflammatory effects in pneumococcal meningitis and prevents cognitive sequel.”  https://www.ncbi.nlm.nih.gov/pubmed/23085269

“Although descriptive, our results demonstrate that chronic treatment with CBD plays an anti-inflammatory role in pneumococcal meningitis. Furthermore, it prevents cognitive damage, possibly representing a new pharmacological approach towards pneumococcal meningitis.” https://www.sciencedirect.com/science/article/pii/S0014299912008485?via%3Dihub

Molecular biology of cannabinoid receptors.

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Abstract

“During the last decade, research on the molecular biology and genetics of cannabinoid receptors has led to a remarkable progress in understanding of the endogenous cannabinoid system, which functions in a plethora of physiological processes in the animal. At present, two types of cannabinoid receptors have been cloned from many vertebrates, and three endogenous ligands (the endocannabinoids arachidonoyl ethanolamide, 2-arachidonoyl glycerol and 2-arachidonoyl-glycerol ether) have been characterized. Cannabinoid receptor type 1 (CB(1)) is expressed predominantly in the central and peripheral nervous system, while cannabinoid receptor type 2 (CB(2)) is present almost exclusively in immune cells. Cannabinoid receptors have not yet been cloned from invertebrates, but binding proteins for endocannabinoids, endocannabinoids and metabolic enzyme activity have been described in a variety of invertebrates except for molting invertebrates such as Caenorhabditis elegans and Drosophila. In the central nervous system of mammals, there is strong evidence emerging that the CB(1) and its ligands comprise a neuromodulatory system functionally interacting with other neurotransmitter systems. Furthermore, the presynaptic localization of CB(1) together with the results obtained from electrophysiological experiments strengthen the notion that in cerebellum and hippocampus and possibly in other regions of the central nervous system, endocannabinoids may act as retrograde messengers to suppress neurotransmitter release at the presynaptic site. Many recent studies using genetically modified mouse lines which lack CB(1) and/or CB(2) finally could show the importance of cannabinoid receptors in animal physiology and will contribute to unravel the full complexity of the cannabinoid system.”

http://www.ncbi.nlm.nih.gov/pubmed/12052031

Cannabinoid signalling regulates inflammation and energy balance: the importance of the brain-gut axis.

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Abstract

“Energy balance is controlled by centres of the brain which receive important inputs from the gastrointestinal tract, liver, pancreas, adipose tissue and skeletal muscle, mediated by many different signalling molecules. Obesity occurs when control of energy intake is not matched by the degree of energy expenditure. Obesity is not only a state of disordered energy balance it is also characterized by systemic inflammation. Systemic inflammation is triggered by the leakage of bacterial lipopolysaccharide through changes in intestinal permeability. The endocannabinoid system, consisting of the cannabinoid receptors, endogenous cannabinoid ligands and their biosynthetic and degradative enzymes, plays vital roles in the control of energy balance, the control of intestinal permeability and immunity. In this review we will discuss how the endocannabinoid system, intestinal microbiota and the brain-gut axis are involved in the regulation of energy balance and the development of obesity-associated systemic inflammation. Through direct and indirect actions throughout the body, the endocannabinoid system controls the development of obesity and its inflammatory complications.”

http://www.ncbi.nlm.nih.gov/pubmed/22269477

[The role of the endocannabinoid system in the regulation of endocrine function and in the control of energy balance in humans].

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Abstract

“The endocannabinoid system has been recently recognized as an important modulatory system in the function of brain, endocrine, and immune tissues. It appears to play a very important regulatory role in the secretion of hormones related to reproductive functions and response to stress. The important elements of this system are: endocannabinoid receptors (types CB1 and CB2), their endogenous ligands (N-arachidonoylethanolamide, 2-arachidonoyl glycerol), enzymes involved in their synthesis and degradation, as well as cannabinoid antagonists. In humans this system also controls energy homeostasis and mainly influences the function of the food intake centers of the central nervous system and gastrointestinal tract activity. The endocannabinoid system regulates not only the central and peripheral mechanisms of food intake, but also lipids synthesis and turnover in the liver and adipose tissue as well as glucose metabolism in muscle cells. Rimonabant, a new and selective central and peripheral cannabinoid-1 receptor (CB1) blocker, has been shown to reduce body weight and improve cardiovascular risk factor (metabolic syndrome) in obese patients by increasing HDL-cholesterol and adiponectin blood levels as well as decreasing LDL-cholesterol, leptin, and C-reactive protein (a proinflammatory marker) concentrations. It is therefore possible to speculate about a future clinical use of CB1 antagonists, as a means of improving gonadotrophin pulsatility and fertilization capacity as well as the prevention of cardiovasculary disease and type 2 diabetes mellitus. Drugs acting as agonists of CB1 receptors (Dronabinol, Dexanabinol) are currently proposed for evaluation as drugs to treat neurodegenerative disorders (Alzheimer’s and Parkinson’s diseases), epilepsy, anxiety, and stroke.”

http://www.ncbi.nlm.nih.gov/pubmed/17369778

Obesity-dependent cannabinoid modulation of proliferation in adult neurogenic regions.

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Abstract

“Endocannabinoid signalling participates in the control of neurogenesis, especially after brain insults. Obesity may explain alterations in physiology affecting neurogenesis, although it is unclear whether cannabinoid signalling may modulate neural proliferation in obese animals. Here we analyse the impact of obesity by using two approaches, a high-fat diet (HFD, 60% fat) and a standard/low-fat diet (STD, 10% fat), and the response to a subchronic treatment with the cannabinoid receptor type 1 (CB1) inverse agonist AM251 (3 mg/kg) on cell proliferation of two relevant neurogenic regions, namely the subventricular zone in the striatal wall of the lateral ventricle (SVZ) and the subgranular zone of the dentate gyrus (SGZ), and also in the hypothalamus given its role in energy metabolism. We found evidence of an interaction between diet-induced obesity and CB1 signalling in the regulation of cell proliferation. AM251 reduced caloric intake and body weight in obese rats, as well as corrected plasma levels of cholesterol and triglycerides. AM251 is shown, for the first time, to modulate cell proliferation in HFD-obese rats only. We observed an increase in the number of 5-bromo-2-deoxyuridine-labelled (BrdU+) cells in the SGZ, but a decrease in the number of BrdU+ cells in the SVZ and the hypothalamus of AM251-treated HFD rats. These BrdU+ cells expressed the neuron-specific βIII-tubulin. These results suggest that obesity may impact cell proliferation in the brain selectively, and provide support for a role of CB1 signalling regulation of neurogenesis in response to obesity.”

http://www.ncbi.nlm.nih.gov/pubmed/21395869

Obesity, the Endocannabinoid System, and Bias Arising from Pharmaceutical Sponsorship

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“Previous research has shown that academic physicians conflicted by funding from the pharmaceutical industry have corrupted evidence based medicine and helped enlarge the market for drugs. Physicians made pharmaceutical-friendly statements, engaged in disease mongering, and signed biased review articles ghost-authored by corporate employees.

 This paper tested the hypothesis that bias affects review articles regarding rimonabant, an anti-obesity drug that blocks the central cannabinoid receptor.

CONCLUSIONS:

The findings are characteristic of bias that arises from financial conflicts of interest, and suggestive of ghostwriting by a common author. Resolutions for this scenario are proposed.

In summary, financial conflicts permeate the system and are by no means limited to corporations referenced in this article, such as Merck, Parke-Davis, Pfizer, Sanofi-Aventis, and Wyeth-Ayerst. On balance, pharmaceutical corporations do good work and aid in humanitarian efforts. For example Sanofi-Aventis provides artemisinin at cost to malaria-endemic countries. Nevertheless, ghost authorship and the corrupting effects of covert financial support must cease. Only three of eight rimonabant review articles disclosed corporate sponsorship; two authors specifically denied conflicts. Lack of disclosure prevents readers from judging the credibility of an author. Medical journals should require stronger author disclosure procedures, and universities should discipline academics who sign ghostwritten articles. This behavior should be regarded as unethical misconduct. More broadly, researchers with conflicts of interest should not be allowed to sit on guideline committees and regulatory boards. Corporate funding of CME programs and review articles should be abolished.

While this paper was under review, Merck halted taranabant RCTs, and Sanofi-Aventis removed rimonabant from the European market. The FDA rejected rimonabant after data submitted by Sanofi-Aventis revealed adverse effects in RIO trials that went unreported in RIO publications [86], including one death in a rimonabant-treated subject (ruled a suicide by the FDA, [86]) that did not appear in the pertinent publication [7]. Although the risk-benefit ratio of cannabinoid receptor blockade may preclude its use for chronic conditions such as obesity and drug or alcohol dependence, cannabinoid receptor blockade could serve in the treatment of acute endocannabinoid dysregulation, such as hepatic cirrhosis, hemorrhagic or endotoxic shock, cardiac reperfusion injury, and doxorubicin-induced cardiotoxicity.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2659447/

 

Rimonabant: a novel selective cannabinoid-1 receptor antagonist for treatment of obesity.

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Abstract

“PURPOSE:

The pharmacology, pharmacokinetics, clinical efficacy, safety, drug interactions, and dosage and administration of rimonabant in the treatment of obesity and related metabolic factors are reviewed.

SUMMARY:

Discovery of the cannabinoid receptors has led to the development of rimonabant, a cannabinoid-1 (CB(1)) antagonist. Selective blockade of this receptor has been shown to lead to decreased appetite and food intake in animal models. Clinical studies have shown that rimonabant 20 mg once daily produces significant decreases in weight and waist circumference in obese human subjects and improves the lipid profile and glucose control. The frequency of metabolic syndrome also decreased significantly with rimonabant 20 mg daily. Limited data are available regarding the pharmacokinetics and pharmacodynamics of rimonabant. Preclinical data have demonstrated a long duration of action. As of yet, no drug-drug, drug-food, or drug-disease interactions have been identified with rimonabant. Adverse reactions occurred rarely, with nausea, dizziness, diarrhea, arthralgia, and back pain being the most common. Psychiatric disorders, including depression and anxiety, were the most common reasons for subjects to withdraw from rimonabant studies. Rimonabant has been shown to be safe for up to two years of treatment. Further research will clarify currently unknown areas, including pharmacokinetics, drug interactions, and the drug’s role in standard therapy.

CONCLUSION:

Rimonabant, a selective CB(1) antagonist, is a novel treatment option for obese and overweight individuals. Significant weight loss, decrease in waist circumference, and improvements in lipid profile and glucose control have been shown in clinical trials of rimonabant.”

http://www.ncbi.nlm.nih.gov/pubmed/17322160

The nonpsychoactive cannabis constituent cannabidiol is an oral anti-arthritic therapeutic in murine collagen-induced arthritis

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“The therapeutic potential of cannabidiol (CBD), the major nonpsychoactive component of cannabis, was explored in murine collagen-induced arthritis (CIA).

CBD was administered after onset of clinical symptoms, and in both models of arthritis the treatment effectively blocked progression of arthritis. CBD was equally effective when administered i.p. or orally.

Clinical improvement was associated with protection of the joints against severe damage.

Taken together, these data show that CBD, through its combined immunosuppressive and anti-inflammatory actions, has a potent anti-arthritic effect in CIA.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC16904/

“In the present study, we report that CBD has a beneficial therapeutic action on established CIA, and we explore its mode of action.”   http://www.pnas.org/content/97/17/9561.long

The endocannabinoid system and neurogenesis in health and disease.

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Consuming plant cannabinoids leads to neurogenesis (birth of neurons), thanks to the endocannabinoid system.

“The endocannabinoid system exerts an important neuromodulatory function in different brain areas and is also known to be involved in the regulation of neural cell fate.

Thus, CB(1) cannabinoid receptors are neuroprotective in different models of brain injury, and their expression is altered in various neurodegenerative diseases. Recent findings have demonstrated the presence of a functional endocannabinoid system in neural progenitor cells that participates in the regulation of cell proliferation and differentiation.

In this Research Update, the authors address the experimental evidence regarding the regulatory role of cannabinoids in neurogenesis and analyze them in the context of those pathological disorders in which cannabinoid function and altered neuronal or glial generation is most relevant, for example, stroke and multiple sclerosis.”