Totality of the Evidence Suggests Prenatal Cannabis Exposure Does Not Lead to Cognitive Impairments: A Systematic and Critical Review

Special issue Frontiers in Psychology“Despite limited data demonstrating pronounced negative effects of prenatal cannabis exposure, popular opinion and public policies still reflect the belief that cannabis is fetotoxic.

This article provides a critical review of results from longitudinal studies examining the impact of prenatal cannabis exposure on multiple domains of cognitive functioning in individuals aged 0 to 22 years.

The current evidence does not suggest that prenatal cannabis exposure alone is associated with clinically significant cognitive functioning impairments.

The current review of the literature found that there are relatively few cognitive alterations noted in offspring exposed to cannabis prenatally.

In general, prenatal cannabis exposure was associated with few effects, negative or positive.”

https://www.frontiersin.org/articles/10.3389/fpsyg.2020.00816/full

Cross-Generational THC Exposure Alters Heroin Reinforcement in Adult Male Offspring.

Drug and Alcohol Dependence“An emerging area of preclinical research has investigated whether drug use in parents prior to conception influences drug responsivity in their offspring.

The present work sought to further characterize such effects with cannabis by examining whether a parental THC history modified locomotor sensitization to morphine and self-administration of heroin in adult progeny.

RESULTS:

Germline THC exposure had no effect on morphine locomotor sensitization. However, F1-THC males displayed a reduced motivation to self-administer heroin relative to F1-Veh males.

CONCLUSIONS:

The present data indicate that parental THC exposure alters the reinforcing properties of heroin in a sex-specific manner. As such, mild to moderate cannabis use during adolescence may alter heroin abuse liability for males in the subsequent generation, but have limited effects on females.”

https://www.ncbi.nlm.nih.gov/pubmed/32386920

https://www.sciencedirect.com/science/article/abs/pii/S0376871620301502?via%3Dihub

Activation of CB1R Promotes Lipopolysaccharide-Induced IL-10 Secretion by Monocytic Myeloid-Derived Suppressive Cells and Reduces Acute Inflammation and Organ Injury.

The Journal of Immunology: 204 (10)“Cannabis sativa and its principal components, Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol, are increasingly being used to treat a variety of medical problems, including inflammatory conditions.

Although studies suggest that the endocannabinoid system has immunomodulatory properties, there remains a paucity of information on the effects of cannabinoids on immunity and on outcomes of infection and injury.

We investigated the effects and mechanism(s) of action of cannabinoid receptor agonists, including Δ9-THC, on inflammation and organ injury in endotoxemic mice.

Administration of Δ9-THC caused a dramatic early upregulation of plasma IL-10 levels, reduced plasma IL-6 and CCL-2 levels, led to better clinical status, and attenuated organ injury in endotoxemic mice. The anti-inflammatory effects of Δ9-THC in endotoxemic mice were reversed by a cannabinoid receptor type 1 (CB1R) inverse agonist (SR141716), and by clodronate-induced myeloid-cell depletion, but not by genetic invalidation or blockade of other putative Δ9-THC receptors, including cannabinoid receptor type 2, TRPV1, GPR18, GPR55, and GPR119. Although Δ9-THC administration reduced the activation of several spleen immune cell subsets, the anti-inflammatory effects of Δ9-THC were preserved in splenectomized endotoxemic mice. Finally, using IL-10-GFP reporter mice, we showed that blood monocytic myeloid-derived suppressive cells mediate the Δ9-THC-induced early rise in circulating IL-10.

These results indicate that Δ9-THC potently induces IL-10, while reducing proinflammatory cytokines, chemokines, and related organ injury in endotoxemic mice via the activation of CB1R. These data have implications for acute and chronic conditions that are driven by dysregulated inflammation, such as sepsis, and raise the possibility that CB1R-signaling may constitute a novel target for inflammatory disorders.”

https://www.ncbi.nlm.nih.gov/pubmed/32385136

https://www.jimmunol.org/content/early/2020/05/07/jimmunol.2000213

Acute and residual mood and cognitive performance of young adults following smoked cannabis.

Pharmacology Biochemistry and Behavior“To examine acute and residual mood and cognitive performance in young adult regular cannabis users following smoked cannabis.

METHODS:

Ninety-one healthy young adults completed this double-blind, placebo-controlled, parallel-groups study. Participants were randomized to receive active (12.5% THC) or placebo cannabis with a 2:1 allocation ratio, and mood [Profile of Mood States (POMS)] and cognitive performance [Hopkins Verbal Learning Test – Revised (HVLT-R), Digit Symbol Substitution Test (DSST), Continuous Performance Test (CPT), grooved pegboard (GPB)] were assessed before and 1, 24, and 48 h after smoking cannabis ad libitum. High and Low THC groups were based on blood THC concentrations.

RESULTS:

One hour after smoking cannabis, compared to Placebo, in both the High and Low THC groups, there were increases in POMS Arousal and Positive Mood, and in the High THC group only, increases in Confusion, Friendliness, and Elation, and a decrease in Fatigue. Increases in Friendliness and Elation in the High THC group remained significant for 24 h. The only significant acute effect of cannabis on cognition was a decrease in the percent of words retained in the HVLT-R in the High THC group compared to Placebo (mean difference = 15.8%, 95% CI = 3.6-28.0%, p = 0.006). Unexpectedly, compared to Placebo, both the High and Low THC groups improved in DSST performance at 48 h (p ≤ 0.016).

CONCLUSIONS:

Under the present experimental conditions, in young regular cannabis users, smoking cannabis ad libitum had significant effects on mood, some of which persisted 24 h later, yet minimal effects on cognition, and no evidence of residual cognitive impairment.”

https://www.ncbi.nlm.nih.gov/pubmed/32360692

“There were few acute effects of cannabis on cognitive performance.”

https://www.sciencedirect.com/science/article/pii/S0091305719306276?via%3Dihub

The impact of naturalistic cannabis use on self-reported opioid withdrawal.

A Case of Mutism Subsequent to Cocaine Abuse - Journal of ...“Four states have legalized medical cannabis for the purpose of treating opioid use disorder. It is unclear whether cannabinoids improve or exacerbate opioid withdrawal. A more thorough examination of cannabis and its impact on specific symptoms of opioid withdrawal is warranted.

METHOD:

Two hundred individuals recruited through Amazon Mechanical Turk with past month opioid and cannabis use and experience of opioid withdrawal completed the survey. Participants indicated which opioid withdrawal symptoms improved or worsened with cannabis use and indicated the severity of their opioid withdrawal on days with and without cannabis.

RESULTS:

62.5% (n = 125) of 200 participants had used cannabis to treat withdrawal. Participants most frequently indicated that cannabis improved: anxiety, tremors, and trouble sleeping. A minority of participants (6.0%, n = 12) indicated cannabis worsened opioid withdrawal, specifically symptoms of yawning, teary eyes, and runny nose. Across all symptoms, more participants indicated that symptoms improved with cannabis compared to those that indicated symptoms worsened with cannabis. Women reported greater relief from withdrawal with cannabis use than men.

DISCUSSION:

These results show that cannabis may improve opioid withdrawal symptoms and that the size of the effect is clinically meaningful. It is important to note that symptoms are exacerbated with cannabis in only a minority of individuals. Prospectively designed studies examining the impact of cannabis and cannabinoids on opioid withdrawal are warranted.”

https://www.ncbi.nlm.nih.gov/pubmed/32359667

“Cannabis alleviates self-reported opioid withdrawal symptoms.”

https://www.journalofsubstanceabusetreatment.com/article/S0740-5472(19)30564-1/pdf

Targeting the Endocannabinoid System in Borderline Personality Disorder.

“Borderline Personality Disorder (BPD) is a chronic debilitating psychiatric disorder characterized mainly by emotional instability, chaotic interpersonal relationships, cognitive disturbance (e.g. dissociation and suicidal thoughts) and maladaptive behaviors. BPD has a high rate of comorbidity with other mental disorders and high burden on society.

In this review, we focus on two compromised brain regions in BPD – the hypothalamus and the corticolimbic system, emphasizing the involvement and potential contribution of the endocannabinoid system (ECS) to improvement in symptoms and coping.

The hypothalamus-regulated endocrine axes (hypothalamic pituitary – gonadal, thyroid & adrenal) have been found to be dysregulated in BPD. There is also substantial evidence for limbic system structural and functional changes in BPD, especially in amygdala and hippocampus, including cortical regions within the corticolimbic system.

Extensive expression of CB1 and CB2 receptors of the ECS has been found in limbic regions and the hypothalamus. This opens new windows of opportunity for treatment with cannabinoids such as cannabidiol (CBD) as no other pharmacological treatment has shown long-lasting improvement in the BPD population to date.

This review aims to show the potential role of the ECS in BPD patients through their most affected brain regions, the hypothalamus and the corticolimbic system. The literature reviewed does not allow for general indications of treatment with CBD in BPD. However, there is enough knowledge to indicate a treatment ratio of high level of CBD to low level of THC.

A randomized controlled trial investigating the efficacy of cannabinoid based treatments in BPD is warranted.”

https://www.ncbi.nlm.nih.gov/pubmed/32351183

http://www.eurekaselect.com/181504/article

Innovative methods for the preparation of medical Cannabis oils with a high content of both cannabinoids and terpenes.

Journal of Pharmaceutical and Biomedical Analysis“Cannabis-based medications are being increasingly used for the treatment of different clinical conditions.

Among all galenic formulations, olive oil extracts from medical Cannabis are the most prescribed ones for their easy preparation and usage. A great variety of methods have been described so far for the extraction of medical Cannabis oils to reach a high yield of Δ9-tetrahydrocannabinol (Δ9-THC), but poor attention has been paid to the preservation of the terpene fraction from the plant, which may contribute to the overall bioactivity of the extracts.

In this context, the present study was aimed at the chemical characterization of different medical Cannabis oils prepared by following both innovative and existing extraction protocols, with particular attention to cannabinoids and terpenes, in order to set up a suitable method to obtain an extract rich in these chemical classes. In particular, six different extraction procedures were followed, based on different techniques, of which all but one included a decarboxylation of the plant material.

The profile of cannabinoids was studied in detail by means of HPLC-ESI-MS/MS, while terpenes were characterized by means both GC-MS and GC-FID techniques coupled with solid-phase microextraction operated in the head-space mode (HS-SPME). An innovative method that is based on the extraction of the oil by dynamic maceration at room temperature from plant inflorescences, which were partially decarboxylated in a closed system at a moderate temperature and partially pre-extracted with ethanol, produced similar yields of bioactive compounds as that obtained by using a microwave-assisted distillation of the essential oil from the plant material, in combination with a maceration extraction of the oil from the residue.

Both these new methods provided a higher efficiency over already existing extraction procedures of medical Cannabis oils and they can be applied to obtain a product with a high therapeutic value.”

https://www.ncbi.nlm.nih.gov/pubmed/32334134

“New methods were developed for the extraction of medical Cannabis oils.”

https://www.sciencedirect.com/science/article/abs/pii/S0731708520303897?via%3Dihub

Cannabis and cannabinoids in cancer pain management.

 Current Opinion in Supportive and Palliative Care | Apps | 148Apps“An increasing number of patients are turning to cannabis and cannabinoids for management of their palliative and nonpalliative cancer pain and other cancer-related symptoms.

Canadians have a legal framework for access to medical cannabis, which provides a unique perspective in a setting lacking robust clinical evidence. This review seeks to delineate the role of cannabis and cannabinoids in cancer pain management and offers insight into the Canadian practice.

RECENT FINDINGS:

A cohort study using nabiximols on advanced cancer pain in patients already optimized on opioids, over 3 weeks, demonstrated improved average pain score. A large observational study of cancer patients using cannabis over 6 months demonstrated a decreased number of patients with severe pain and decreased opioid use, whereas the number of patients reporting good quality of life increased.

SUMMARY:

Good preclinical animal data and a large body of observational evidence point to the potential efficacy of cannabinoids for cancer pain management. However, there are relatively weak data pointing to clinical efficacy from clinical trial data to date. In Canada, the burgeoning cannabis industry has driven the population to embrace a medicine before clinical evidence. There remains a need for high-quality randomized controlled trials to properly assess the effectiveness and safety of medical cannabis, compared with placebo and standard treatments for cancer-related symptoms.”

https://www.ncbi.nlm.nih.gov/pubmed/32332209

https://journals.lww.com/pages/results.aspx?txtKeywords=10.1097%2fSPC.0000000000000493

Novel approaches and current challenges with targeting the endocannabinoid system.

 Publication Cover“The pathophysiological relevance of the endocannabinoid system has been widely demonstrated in a variety of diseases including cancer, neurological disorders, and metabolic issues. Therefore, targeting the receptors and the endogenous machinery involved in this system can provide a successful therapeutic outcome.

Ligands targeting the canonical cannabinoid receptors, CB1 and CB2, along with inhibitors of the endocannabinoid enzymes have been thoroughly studied in diverse disease models. In fact, phytocannabinoids such as cannabidiol or Δ9-tetrahydrocannabinol are currently on the market for the management of neuropathic pain due to spasticity in multiple sclerosis or seizures in children epilepsy amongst others.

Expert opinion: Even if orthosteric CB1 and CB2 ligands are on the forefront in cannabinoid clinical research, emerging strategies such as allosteric or biased modulation of these receptors along with controlled off-targets effects may increase the therapeutic potential of cannabinoids.”

https://www.ncbi.nlm.nih.gov/pubmed/32336154

“Multi-target approaches could be promising strategies for the treatment of endocannabinoid system-related disorders. The authors believe that phytocannabinoids are at the forefront of future clinical research.”

https://www.tandfonline.com/doi/abs/10.1080/17460441.2020.1752178?journalCode=iedc20

Effects of THC/CBD oromucosal spray on spasticity-related symptoms in people with multiple sclerosis: results from a retrospective multicenter study.

 Journal cover“The approval of 9-δ-tetrahydocannabinol (THC)+cannabidiol (CBD) oromucosal spray (Sativex®) in Italy as an add-on medication for the management of moderate to severe spasticity in multiple sclerosis (MS) has provided a new opportunity for MS patients with drug-resistant spasticity.

We aimed to investigate the improvement of MS spasticity-related symptoms in a large cohort of patients with moderate to severe spasticity in daily clinical practice.

CONCLUSION:

Our study confirmed that the therapeutic benefit of cannabinoids may extend beyond spasticity, improving spasticity-related symptoms even in non-NRS responder patients.”

https://www.ncbi.nlm.nih.gov/pubmed/32335779

https://link.springer.com/article/10.1007%2Fs10072-020-04413-6