Cannabinoids, Blood-Brain Barrier, and Brain Disposition.

Image result for pharmaceutics“Potential therapeutic actions of the cannabinoids delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) are based on their activity as analgesics, anti-emetics, anti-inflammatory agents, anti-seizure compounds.

THC and CBD lipophilicity and their neurological actions makes them candidates as new medicinal approaches to treat central nervous system (CNS) diseases. However, they show differences about penetrability and disposition in the brain.

The present article is an overview about THC and CBD crossing the blood-brain barrier (BBB) and their brain disposition. Several findings indicate that CBD can modify the deleterious effects on BBB caused by inflammatory cytokines and may play a pivotal role in ameliorating BBB dysfunction consequent to ischemia. Thus supporting the therapeutic potential of CBD for the treatment of ischemic and inflammatory diseases of CNS.

Cannabinoids positive effects on cognitive function could be also considered through the aspect of protection of BBB cerebrovascular structure and function, indicating that they may purchase substantial benefits through the protection of BBB integrity. Delivery of these cannabinoids in the brain following different routes of administration (subcutaneous, oral, and pulmonary) is illustrated and commented. Finally, the potential role of cannabinoids in drug-resistance in the clinical management of neurological or psychiatric diseases such as epilepsy and schizophrenia is discussed on the light of their crossing the BBB.”

https://www.ncbi.nlm.nih.gov/pubmed/32183416

 

Cannabinoids Improve Gastrointestinal Symptoms in a Parenteral Nutrition-Dependent Patient With Chronic Intestinal Pseudo-Obstruction.

Journal of Parenteral and Enteral Nutrition“Chronic intestinal pseudo-obstruction (CIPO) is a rare and challenging cause of pediatric intestinal failure, requiring long-term parenteral nutrition in most cases. Despite optimal management, some patients experience chronic abdominal pain and recurrent obstructive episodes with a major impact on their quality of life.

Cannabinoids have been successfully used in some conditions. However, their use in CIPO has never been reported in the literature.

We report a case of successful use of medicinal cannabinoids in a patient with CIPO, resulting in a significant reduction of abdominal pain, vomiting, and subocclusive episodes and increased appetite and weight, without major adverse events.

Although further observations are required to consolidate these findings, this case may be helpful for other patients suffering from the same condition.”

https://www.ncbi.nlm.nih.gov/pubmed/32181915

https://onlinelibrary.wiley.com/doi/abs/10.1002/jpen.1821

Analgesic Effects of Cannabinoids for Chronic Non-cancer Pain: a Systematic Review and Meta-Analysis with Meta-Regression.

SpringerLink “There is growing interest in using cannabinoids for chronic pain.

We performed a systematic review and meta-analysis of randomized controlled trials to evaluate the analgesic efficacy and adverse effects of cannabinoids for chronic non-cancer pain.

PubMed, EMBASE, Web of Science, Cochrane CENTRAL and clinicaltrials.gov were searched up to December 2018. Information on the type, dosage, route of administration, pain conditions, pain scores, and adverse events were extracted for qualitative analysis. Meta-analysis of analgesic efficacy was performed. Meta-regression was performed to compare the analgesic efficacy for different pain conditions (neuropathic versus non-neuropathic pain). Risk of bias was assessed by The Cochrane Risk of Bias tool, and the strength of the evidence was assessed using the Grade of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

Forty-three randomized controlled trials were included. Meta-analysis was performed for 33 studies that compared cannabinoids to placebo, and showed a mean pain score (scale 0-10) reduction of -0.70 (p < 0.001, random effect). Meta-regression showed that analgesic efficacy was similar for neuropathic and non-neuropathic pain (Difference = -0.14, p = 0.262).

Inhaled, oral, and oromucosal administration all provided statistically significant, but small reduction in mean pain score (-0.97, -0.85, -0.45, all p < 0.001). Incidence of serious adverse events was rare, and non-serious adverse events were usually mild to moderate. Heterogeneity was moderate.

The GRADE level of evidence was low to moderate. Pain intensity of chronic non-cancer patients was reduced by cannabinoids consumption, but effect sizes were small. Efficacy for neuropathic and non-neuropathic pain was similar.”

https://www.ncbi.nlm.nih.gov/pubmed/32172501

https://link.springer.com/article/10.1007%2Fs11481-020-09905-y

The role of the cannabinoid system in opioid analgesia and tolerance.

“Opioid receptor agonist drugs, such as morphine, are very effective for treating chronic and severe pain; but, tolerance can develop with long-term use. Although there is a lot of information about the pathophysiological mechanisms of opioid tolerance, it is still not fully clarified. Suggested mechanisms for opioid tolerance include opioid receptor desensitisation, reduction of sensitivity G-proteins, activation of mitogen-activated protein kinase (MAPK), altered intracellular signaling pathway including nitric oxide, and activation of mammalian target of rapamycin (mTOR).

One way to reduce opioid tolerance and increase the analgesic potential is to use low doses. Combination of cannabinoids with opioids has been shown to manifest reduce the opioid dose. Experimental studies revealed an interaction of the endocannabinoid system and opioid antinociception.

Cannabinoid and opioid receptor systems use common pathways in the formation of analgesic effect and demonstrate their activity via G protein coupled receptors (GPCR). Cannabinoid drugs modulate opioid analgesic activity at a number of distinct levels within the cell, ranging from direct receptor associations, to post-receptor interactions through shared signal transduction pathways.

This review summarizes the data indicating that with combining cannabinoids and opioids drugs may be able to produce long-term analgesic effects, while preventing the opioid analgesic tolerance.”

https://www.ncbi.nlm.nih.gov/pubmed/32167427

http://www.eurekaselect.com/180186/article

Cannabis and the Cornea.

Publication Cover

“While cannabis has the potential to reduce corneal pain, cannabinoids might induce side effects. This review article examines the effects of cannabinoids on the cornea. As more states and countries consider the legalization of adult cannabis use, health-care providers will need to identify ocular effects of cannabis consumption.

Methods: Studies included in this review examined the connection between cannabis and the cornea, more specifically anti-nociceptive and anti-inflammatory actions of cannabinoids. NCBI Databases from 1781 up to December 2019 were consulted.

Conclusion: More than half of the studies examined the therapeutic effects of cannabinoids on the cornea. As the field is still young, more studies should be conducted to develop safe cannabinoid treatments for corneal diseases.

Influence of cannabinoids upon nerve-evoked skeletal muscle contraction.

Neuroscience Letters“Endocannabinoids play important roles in regulating CNS synaptic function and peripheral metabolism, but cannabinoids can also act acutely to modulate contraction strength in skeletal muscle.

Nerve terminals and the skeletal muscle sarcolemma express components of the cannabinoid signaling system.

Endocannabinoids, N-arachidonylethanolamine (anandamide, AEA) and 2-arachidonoyl-glycerol (2-AG), are produced by skeletal muscle. They may be involved in the acute regulation of neuromuscular transmission, by adjusting the parameters for quantal acetylcholine release from the motor nerve terminal. Downstream of neuromuscular transmission, cannabinoids may also act to limit the efficiency of excitation-contraction coupling.

Improved understanding of the distinct signaling actions of particular cannabinoid compounds and their receptor/transduction systems will help advance our understanding of the role of endocannabinoids in skeletal muscle physiology.

Cannabinoids might also offer the potential to develop new pharmacotherapeutics to treat neuromuscular disorders that affect muscle strength.”

https://www.ncbi.nlm.nih.gov/pubmed/32156612

https://www.sciencedirect.com/science/article/abs/pii/S0304394020301701?via%3Dihub

Melatonin and cannabinoids: mitochondrial-targeted molecules that may reduce inflammaging in neurodegenerative diseases.

Image result for histology and histopathology“Generally, the development and progression of neurodegenerative diseases are associated with advancing age, so they are usually diagnosed in late adulthood. A primary mechanism underlying the onset of neurodegenerative diseases is neuroinflammation. Based on this background, the concept of “neuroinflammaging” has emerged. In this deregulated neuroinflammatory process, a variety of immune cells participate, especially glial cells, proinflammatory cytokines, receptors, and subcellular organelles including mitochondria, which are mainly responsible for maintaining redox balance at the cellular level. Senescence and autophagic processes also play a crucial role in the neuroinflammatory disease associated with aging.

Of particular interest, melatonin, cannabinoids, and the receptors of both molecules which are closely related, exert beneficial effects on the neuroinflammatory processes that precede the onset of neurodegenerative pathologies such as Parkinson’s and Alzheimer’s diseases. Some of these neuroprotective effects are fundamentally related to its anti-inflammatory and antioxidative actions at the mitochondrial level due to the strategic functions of this organelle. The aim of this review is to summarize the most recent advances in the study of neuroinflammation and neurodegeneration associated with age and to consider the use of new mitochondrial therapeutic targets related to the endocannabinoid system and the pineal gland.”

https://www.ncbi.nlm.nih.gov/pubmed/32154907

https://www.hh.um.es/Abstracts/Vol_/_/__18212.htm

Antinociceptive and Immune Effects of Delta-9-tetrahydrocannabinol or Cannabidiol in Male Versus Female Rats with Persistent Inflammatory Pain.

Journal of Pharmacology and Experimental Therapeutics: 373 (1)

“Chronic pain is the most common reason reported for using medical cannabis.

The goal of this research was to determine if the two primary phytocannabinoids, THC and CBD, are effective treatments for persistent inflammatory pain.

These results suggest that THC may be more beneficial than CBD for reducing inflammatory pain, in that THC maintains its efficacy with short-term treatment in both sexes, and does not induce immune activation.

SIGNIFICANCE STATEMENT: CBDs and THCs pain-relieving effects are examined in male and female rats with persistent inflammatory pain to determine if individual phytocannabinoids could be a viable treatment for men and women with chronic inflammatory pain. Additionally, sex differences in the immune response to an adjuvant and to THC and CBD are characterized to provided preliminary insight into immune-related effects of cannabinoid-based therapy for pain.”

https://www.ncbi.nlm.nih.gov/pubmed/32179573

http://jpet.aspetjournals.org/content/early/2020/03/16/jpet.119.263319

An overview of cannabis based treatment in Crohn’s disease.

 Publication Cover“Cannabis use among inflammatory bowel disease (IBD) patients is common. There are many studies of various laboratory models demonstrating the anti-inflammatory effect of cannabis, but their translation to human disease is still lacking.

Areas covered: The cannabis plant contains many cannabinoids, that activate the endocannabinoid system. The two most abundant phytocannabinoids are the psychoactive Tetrahydrocannabinol (THC), and the (mostly) anti-inflammatory cannabidiol (CBD). Approximately 15% of IBD patients use cannabis to ameliorate disease symptoms. Unfortunately, so far there are only three small placebo controlled study regarding the use of cannabis in active Crohns disease, combining altogether 93 subjects. Two of the studies showed significant clinical improvement but no improvement in markers of inflammation.

Expert opinion: Cannabis seems to have a therapeutic potential in IBD. This potential must not be neglected; however, cannabis research is still at a very early stage. The complexity of the plant and the diversity of different cannabis chemovars create an inherent difficulty in cannabis research. We need more studies investigating the effect of the various cannabis compounds. These effects can then be investigated in randomized placebo controlled clinical trials to fully explore the potential of cannabis treatment in IBD.”

https://www.ncbi.nlm.nih.gov/pubmed/32149543

https://www.tandfonline.com/doi/abs/10.1080/17474124.2020.1740590?journalCode=ierh20

Evaluation of pharmacokinetics and acute anti-inflammatory potential of two oral cannabidiol preparations in healthy adults.

Phytotherapy Research“Cannabidiol (CBD) is a dietary supplement with numerous purported health benefits and an expanding commercial market. Commercially available CBD preparations range from tinctures, oils, and powders, to foods and beverages.

Despite widespread use, information regarding bioavailability of these formulations is limited. The purpose of this study was to test the bioavailability of two oral formulations of CBD in humans and explore their potential acute anti-inflammatory activity.

This study provides pilot data for designing and powering future studies to establish the anti-inflammatory potential and bioavailability of a larger variety of commercial CBD products consumed by humans.”

https://www.ncbi.nlm.nih.gov/pubmed/32147925

https://onlinelibrary.wiley.com/doi/abs/10.1002/ptr.6651