Identification of SARS-CoV-2 Main Protease Inhibitors from a Library of Minor Cannabinoids by Biochemical Inhibition Assay and Surface Plasmon Resonance Characterized Binding Affinity


“The replication of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is mediated by its main protease (Mpro), which is a plausible therapeutic target for coronavirus disease 2019 (COVID-19). Although numerous in silico studies reported the potential inhibitory effects of natural products including cannabis and cannabinoids on SARS-CoV-2 Mpro, their anti-Mpro activities are not well validated by biological experimental data. Herein, a library of minor cannabinoids belonging to several chemotypes including tetrahydrocannabinols, cannabidiols, cannabigerols, cannabichromenes, cannabinodiols, cannabicyclols, cannabinols, and cannabitriols was evaluated for their anti-Mpro activity using a biochemical assay. Additionally, the binding affinities and molecular interactions between the active cannabinoids and the Mpro protein were studied by a biophysical technique (surface plasmon resonance; SPR) and molecular docking, respectively. Cannabinoids tetrahydrocannabutol and cannabigerolic acid were the most active Mpro inhibitors (IC50 = 3.62 and 14.40 μM, respectively) and cannabigerolic acid had a binding affinity KD=2.16×10-4 M). A preliminary structure and activity relationship study revealed that the anti-Mpro effects of cannabinoids were influenced by the decarboxylation of cannabinoids and the length of cannabinoids’ alkyl side chain. Findings from the biochemical, biophysical, and computational assays support the growing evidence of cannabinoids’ inhibitory effects on SARS-CoV-2 Mpro.”

“In summary, the inhibitory effects of a collection of cannabinoids on SARS-CoV-2 3CL Mpro were screened by a biochemical assay. Several minor cannabinoids (e.g., THCB and CBGA) showed promising anti-Mpro activity. In addition, we observed that decarboxylated cannabinoids, such as CBG and CBD, showed undermined inhibition capacity, as compared to the precursing cannabinoid acids (i.e., CBGA and CBDA, respectively). This SAR was supported by the binding affinities between these cannabinoids and the Mpro protein obtained from the SPR assays. Furthermore, the impact of the length of the alkyl side chain of cannabinoids on their anti-Mpro activity was explored. Our study is the first to evaluate the anti-Mpro activity of minor cannabinoids and their mechanisms of action, which contribute to a better understanding of cannabinoids’ potential roles in the management of COVID-19.”

Analysis of Anti-Cancer and Anti-Inflammatory Properties of 25 High-THC Cannabis Extracts


“Cannabis sativa is one of the oldest cultivated plants. Many of the medicinal properties of cannabis are known, although very few cannabis-based formulations became prescribed drugs. Previous research demonstrated that cannabis varieties are very different in their medicinal properties, likely due to the entourage effect-the synergistic or antagonistic effect of various cannabinoids and terpenes.

In this work, we analyzed 25 cannabis extracts containing high levels of delta-9-tetrahydrocannabinol (THC). We used HCC1806 squamous cell carcinoma and demonstrated various degrees of efficiency of the tested extracts, from 66% to 92% of growth inhibition of cancer cells.

Inflammation was tested by induction of inflammation with TNF-α/IFN-γ in WI38 human lung fibroblasts. The efficiency of the extracts was tested by analyzing the expression of COX2 and IL6; while some extracts aggravated inflammation by increasing the expression of COX2/IL6 by 2-fold, other extracts decreased inflammation, reducing expression of cytokines by over 5-fold.

We next analyzed the level of THC, CBD, CBG and CBN and twenty major terpenes and performed clustering and association analysis between the chemical composition of the extracts and their efficiency in inhibiting cancer growth and curbing inflammation.

A positive correlation was found between the presence of terpinene (pval = 0.002) and anti-cancer property; eucalyptol came second, with pval of 0.094. p-cymene and β-myrcene positively correlated with the inhibition of IL6 expression, while camphor correlated negatively. No significant correlation was found for COX2. We then performed a correlation analysis between cannabinoids and terpenes and found a positive correlation for the following pairs: α-pinene vs. CBD, p-cymene vs. CBGA, terpenolene vs. CBGA and isopulegol vs. CBGA.

Our work, thus, showed that most of high-THC extracts demonstrate anti-cancer activity, while only certain selected extracts showed anti-inflammatory activity. Presence of certain terpenes, such as terpinene, eucalyptol, cymene, myrcene and camphor, appear to have modulating effects on the activity of cannabinoids.”

“Cannabis sativa is a plant with a long history of consumption as food and medicine. Delta-9-tetrahydrocannabinol (THC) is one of the main cannabinoids in cannabis; it has many properties, including anti-cancer, anti-inflammatory, analgetic and others.”

Preoperative cannabis use does not increase opioid utilization following primary total hip arthroplasty in a propensity matched analysis


“Purpose: The recreational and medical use of cannabis is being legalized worldwide. Its use has been linked to an increased risk of developing opioid use disorders. As opioids continue to be prescribed after total hip arthroplasty (THA), the influence that preoperative cannabis use may have on postoperative opioid consumption remains unknown. The purpose of this study was to assess the relationship between preoperative cannabis use and opioid utilization following primary THA.

Methods: We identified all patients over the age of 18 who underwent unilateral, primary THA for a diagnosis of osteoarthritis at a single institution from February 2019 to April 2021. Our cohort was grouped into current cannabis users (within 6 months of surgery) and those who reported never using cannabis. One hundred and fifty-six current users were propensity score matched 1:6 with 936 never users based on age, sex, BMI, history of chronic pain, smoking status, history of anxiety/depression, ASA classification and type of anesthesia. Outcomes included inpatient and postdischarge opioid use in morphine milligram equivalents.

Results: Total inpatient opioid utilization, opioids refilled, and total opioids used within 90 postoperative days were similar between the groups.

Conclusion: In propensity score matched analyses, preoperative cannabis use was not independently associated with an increase in inpatient or outpatient, 90-days opioid consumption following elective THA.”

Does cannabis use predict aggressive or violent behavior in psychiatric populations? A systematic review

Publication Cover

“Background: Despite an increase in information evaluating the therapeutic and adverse effects of cannabinoids, many potentially important clinical correlates, including violence or aggression, have not been adequately investigated.Objectives: In this systematic review, we examine the published evidence for the relationship between cannabis and aggression or violence in individuals with psychiatric disorders.Methods: Following PRISMA guidelines, articles in English were searched on PubMed, Google Scholar, MEDLINE, and PsycINFO from database inception to January 2022. Data for aggression and violence in people with psychiatric diagnoses were identified during the searches.Results: Of 391 papers identified within the initial search, 15 studies met inclusion criteria. Cross-sectional associations between cannabis use and aggression or violence in samples with post-traumatic stress disorder (PTSD) were found. Moreover, a longitudinal association between cannabis use and violence and aggression was observed in psychotic-spectrum disorders. However, the presence of uncontrolled confounding factors in the majority of included studies precludes any causal conclusions.Conclusion: Although cannabis use is associated with aggression or violence in individuals with PTSD or psychotic-spectrum disorders, causal conclusions cannot be drawn due to methodological limitations observed in the current literature. Well-controlled, longitudinal studies are needed to ascertain whether cannabis plays a causal role on subsequent violence or aggression in mental health disorders.”

Cannabidiol and Delta-9-Tetrahydrocannabinol Interactions in Male and Female Rats with Persistent Inflammatory Pain

The Journal of Pain

“Cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC), two of the primary constituents of cannabis, are used by some individuals to self-treat chronic pain. It is unclear whether the pain-relieving effects of CBD alone and in combination with THC are consistent across genders and among types of pain.

The present study compared the effects of CBD and THC given alone and in combination in male and female rats with Complete Freund’s adjuvant-induced inflammatory pain.

After induction of hindpaw inflammation, vehicle, CBD (0.05-2.5 mg/kg), THC (0.05-2.0 mg/kg), or a CBD:THC combination (3:1, 1:1, or 1:3 dose ratio) was administered i.p. twice daily for three days. Then on day four, mechanical allodynia, thermal hyperalgesia, weight-bearing, and locomotor activity were assessed 0.5-4 h after administration of the same dose combination. Hindpaw edema and open field (anxiety-like) behaviors were measured thereafter.

THC alone was anti-allodynic and anti-hyperalgesic, and decreased paw thickness, locomotion, and open field behaviors. CBD alone was anti-allodynic and anti-hyperalgesic. When combined with THC, CBD tended to decrease THC effects on pain-related behaviors and exacerbate THC-induced anxiety-like behaviors, particularly in females.

These results suggest that at the doses tested, CBD-THC combinations may be less beneficial than THC alone for the treatment of chronic inflammatory pain.

PERSPECTIVE: The present study compared CBD and THC effects alone and in combination in male and female rats with persistent inflammatory pain. This study could help clinicians who prescribe cannabis-based medicines for inflammatory pain conditions determine which cannabis constituents may be most beneficial.”

“THC and CBD each reduced chronic inflammatory pain (allodynia and hyperalgesia) in rats.”

Chronic delta-9-tetrahydrocannabinol (THC) treatment counteracts SIV-induced modulation of proinflammatory microRNA cargo in basal ganglia-derived extracellular vesicles

Journal of Neuroinflammation logo

“Background: Early invasion of the central nervous system (CNS) by human immunodeficiency virus (HIV) (Gray et al. in Brain Pathol 6:1-15, 1996; An et al. in Ann Neurol 40:611-6172, 1996), results in neuroinflammation, potentially through extracellular vesicles (EVs) and their micro RNAs (miRNA) cargoes (Sharma et al. in FASEB J 32:5174-5185, 2018; Hu et al. in Cell Death Dis 3:e381, 2012). Although the basal ganglia (BG) is a major target and reservoir of HIV in the CNS (Chaganti et al. in Aids 33:1843-1852, 2019; Mintzopoulos et al. in Magn Reson Med 81:2896-2904, 2019), whether BG produces EVs and the effect of HIV and/or the phytocannabinoid-delta-9-tetrahydrocannabinol (THC) on BG-EVs and HIV neuropathogenesis remain unknown.

Methods: We used the simian immunodeficiency virus (SIV) model of HIV and THC treatment in rhesus macaques (Molina et al. in AIDS Res Hum Retroviruses 27:585-592, 2011) to demonstrate for the first time that BG contains EVs (BG-EVs), and that BG-EVs cargo and function are modulated by SIV and THC. We also used primary astrocytes from the brains of wild type (WT) and CX3CR1+/GFP mice to investigate the significance of BG-EVs in CNS cells.

Results: Significant changes in BG-EV-associated miRNA specific to SIV infection and THC treatment were observed. BG-EVs from SIV-infected rhesus macaques (SIV EVs) contained 11 significantly downregulated miRNAs. Remarkably, intervention with THC led to significant upregulation of 37 miRNAs in BG-EVs (SIV-THC EVs). Most of these miRNAs are predicted to regulate pathways related to inflammation/immune regulation, TLR signaling, Neurotrophin TRK receptor signaling, and cell death/response. BG-EVs activated WT and CX3CR1+/GFP astrocytes and altered the expression of CD40, TNFα, MMP-2, and MMP-2 gene products in primary mouse astrocytes in an EV and CX3CR1 dependent manners.

Conclusions: Our findings reveal a role for BG-EVs as a vehicle with potential to disseminate HIV- and THC-induced changes within the CNS.”

“In summary, the findings of this study suggest that HIV/SIV infection reprograms the BG leading to the release of pathogenic EVs that may potentially promote CNS inflammation and toxicity. However, cannabinoid mediated modulation of EV cargo composition as shown in this study maybe a mechanism for the regulation of HIV/SIV-induced changes. This is significant, because exploration of the potential of THC EVs in a preclinical animal model may be logical to investigate whether the clinical advantages of THC EVs will result in beneficial outcomes. The findings of this study also pave the way for investigation into the effects of the combined administration of THC:CBD [1:1 or 1:3 ratio] on neuroinflammation and their effects on BG-EV composition and function. The implication of our findings goes beyond HIV-induced inflammation. Glia cells (microglia and astrocytes) are involved in the pathogenesis of pain. Activated/reactive astrocytes play a role in neuropathic pain, inflammatory pain, as well as bone cancer pain. Activated astrocytes are also involved in Parkinson’s disease, spinal cord injury, and traumatic brain injury. In line with their role in the pathogenesis of pain, studies are warranted to assess the effect of CNS EVs in mediating the development and maintenance of pain.”

Neuroprotective potential of Cannabis sativa-based oils in Caenorhabditis elegans

Scientific Reports

“Substances from the Cannabis sativa species, especially cannabidiol (CBD) and Delta-9-tetrahydrocannabinol (Δ9-THC), have attracted medical attention in recent years. The actions of these two main cannabinoids modulate the cholinergic nervous system (CholNS) involving development, synaptic plasticity, and response to endogenous and environmental damage, as a characteristic of many neurodegenerative diseases.

The dynamics of these diseases are mediated by specific neurotransmitters, such as the GABAergic nervous system (GNS) and the CholNS. The nematode Caenorhabditis elegans is an important experimental model, which has different neurotransmitter systems that coordinate its behavior and has a transgene strain that encodes the human β-amyloid 1-42 peptide in body wall muscle, one of the main proteins involved in Alzheimer´s disease.

Therefore, the objective of this study was to evaluate the protective potential of terpenoids found in C. sativa in the GNS and CholNS of C. elegans. The effect of two C. sativa oils with variations in CBD and THC concentrations on acetylcholinesterase (AChE) activity, lipid peroxidation, and behavior of C. elegans was evaluated.

C. sativa oils were efficient in increasing pharyngeal pumping rate and reducing defecation cycle, AChE activity, and ROS levels in N2 strains. In the muscle:Abeta1-42 strain, mainly when using CBD oil, worm movement, body bends, and pharyngeal pumping were increased, with a reduced AChE activity.

Consequently, greater investments in scientific research are needed, in addition to breaking the taboo on the use of the C. sativa plant as an alternative for medicinal use, especially in neurodegenerative diseases, which have already shown positive initial results.”

Editorial: Medicinal Cannabis: Evolution of therapeutic use, future approaches and other implications

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“Cannabis has been used in even the oldest traditional medicines available. In the last century, negative attention has prevailed regarding the psychotropic and abuse potential. For this reason, Cannabis has been banned and declared illegal in many countries. In recent years, however, there has been a more in-depth evaluation of the legalization of cannabinoids for medical use in several countries following heightened media attention and reports of effectiveness, although not always thoroughly backed up by scientific evidence. The official introduction of pharmaceutical-grade Cannabis inflorescences for medicinal purposes has allowed physicians and pharmacists, to prescribe and prepare several Cannabis preparations legally. Such products are currently being administered to patients without their efficacy being evaluated in controlled studies: for each patient the composition and route of administration may differ. In addition, many advanced administration systems have been developed or are still under development, but few clinical trials have been completed.

In this context, this Research Topic focused on the in-depth analysis of the legal, technological and pharmacological aspects related to the medical use of Cannabis-based formulations.

Anil et al. have directed their research specifically on the activity of Cannabis for medical use in the context of inflammatory processes. Although activities in this area are plausible, the high number of active molecules produced by Cannabis and simultaneously administered through the extractive products normally used in therapy, has not yet made it possible to identify their specific mechanisms of action. Once the modalities of action of the active molecules have been clarified, it might be of interest to use purified mixtures to obtain a more significant activity potentially (Anil et al.).

Specific literature reviews were then done for some pathologies such as when Xin et al. investigated the potential therapeutic effect of CBD in bone diseases. Even in this case, further studies are needed to evaluate the benefits and risks of cannabinoids’ use (Xin et al.).

A large part of the clinical research relating to Cannabis for medical use concerns its use in the context of diseases of the central nervous system. Ortiz et al. examined evidence supporting the therapeutic utility of cannabinoids for treating neurodegenerative diseases, pain, mood disorders, and substance use disorders. Important considerations were also made on the methods of formulation and the routes of administration (Ortiz et al.). Lacroix et al. Also considered Cannabis in neurological disorders stressing that currently most of the scientific data supports the potential therapeutic use of Cannabis but, as much as patients request it, the knowledge is still too little in-depth. It is therefore certainly urgent to manage clinical trials to provide stronger and safer evidence (Lacroix et al.).

Procaccia et al. discussed how phytocannabinoid profiles differed between plants according to chemovar types and examined the main factors influencing the accumulation of secondary metabolites in the plant, including genotype, growing conditions, processing, storage and the delivery route; the authors highlighted how these factors make the use of Cannabis in therapy highly complex (Procaccia et al.).

In addition to the more well-known compounds such as THC and CBD, Cannabis produces over 120 other phytocannabinoids. The use of THC is associated with acute psychotropic effects that could potentially be avoided considering that minor cannabinoids and their chemical counterparts could offer the same potential benefits without the same adverse effects. In this regard, Walsh et al. reviewed the literature to provide an overview of the endocannabinoid system, phytocannabinoid biosynthesis and a discussion on molecular pharmacology. Potential therapeutic uses of minor cannabinoids underlining that future studies will have to rigorously evaluate these compounds’ risk/benefit ratio (Walsh et al.).

The interest in molecules other than cannabinoids such as terpenes is certainly relevant. This interest has grown even greater since the possibility of an “entourage” effect between the active molecules of Cannabis has been postulated. Accordingly, Finlay et al. in their study examined whether some terpenes acted directly on cannabinoid receptors. From the results obtained, it was not possible to exclude the existence of an entourage effect. Still, this cannot be linked to a direct action of the terpenes on the cannabinoid receptors. However, the pharmacological mechanism underlying this substances activity remains to be thoroughly investigated (Finlay et al.).

Maayah et al. pointed out that full-spectrum Cannabis extracts have been used in clinical trials to treat various diseases. However, despite their efficacy, their potential use in therapy may be limited by possible behavioural side effects. These researchers then successfully worked on experimental animals to identify a panel of blood metabolites predicting behavioural effects (Maayah et al.).

Pennypacker et al. have evaluated whether the products available on the market in the United States of America are consistent in the concentration of cannabinoids, with the literature indications for use in therapy. Overall, the results of this study have been defined by the authors as alarming as current product offerings do not reflect scientific evidence (Pennypacker et al.).

In the regulatory context MacPhail et al. have analysed the trend of prescriptions in Australia over the last 5 years, noting a substantial increase in prescriptions over time that does not actually reflect a worsening of the pathological conditions of the population but rather a greater prescription linked to greater knowledge and acceptance of this type of therapy (MacPhail et al.).

As regards the use in therapy of medical Cannabis, the current regulations have been analysed by Baratta et al. in those countries where clinical studies have recently been conducted. The results of the trials have been crossed with the pathologies for which the current legislation provides that it is possible to prescribe Cannabis allowing relevant considerations (Baratta et al.).

From all the publications collected, it is clear that there is a great interest in the enormous potential of Cannabis in the medical field but also a widespread awareness of the extreme need to conduct in-depth research that clarifies the mechanisms of action of the quantity of components present in the phytocomplex of this plant species.”

Modulation of type 1 cannabinoid receptor activity by cannabinoid by-products from Cannabis sativa and non-cannabis phytomolecules

Frontiers - Crunchbase Company Profile & Funding

“Cannabis sativa contains more than 120 cannabinoids and 400 terpene compounds (i.e., phytomolecules) present in varying amounts. Cannabis is increasingly available for legal medicinal and non-medicinal use globally, and with increased access comes the need for a more comprehensive understanding of the pharmacology of phytomolecules. The main transducer of the intoxicating effects of Cannabis is the type 1 cannabinoid receptor (CB1R). ∆9-tetrahydrocannabinolic acid (∆9-THCa) is often the most abundant cannabinoid present in many cultivars of Cannabis. Decarboxylation converts ∆9-THCa to ∆9-THC, which is a CB1R partial agonist. Understanding the complex interplay of phytomolecules-often referred to as “the entourage effect”-has become a recent and major line of inquiry in cannabinoid research. Additionally, this interest is extending to other non-Cannabis phytomolecules, as the diversity of available Cannabis products grows. Here, we chose to focus on whether 10 phytomolecules (∆8-THC, ∆6a,10a-THC, 11-OH-∆9-THC, cannabinol, curcumin, epigallocatechin gallate, olivetol, palmitoylethanolamide, piperine, and quercetin) alter CB1R-dependent signaling with or without a co-treatment of ∆9-THC. Phytomolecules were screened for their binding to CB1R, inhibition of forskolin-stimulated cAMP accumulation, and βarrestin2 recruitment in Chinese hamster ovary cells stably expressing human CB1R. Select compounds were assessed further for cataleptic, hypothermic, and anti-nociceptive effects on male mice. Our data revealed partial agonist activity for the cannabinoids tested, as well as modulation of ∆9-THC-dependent binding and signaling properties of phytomolecules in vitro and in vivo. These data represent a first step in understanding the complex pharmacology of Cannabis– and non-Cannabis-derived phytomolecules at CB1R and determining whether these interactions may affect the physiological outcomes, adverse effects, and abuse liabilities associated with the use of these compounds.”

Endocannabinoid System and the Otolaryngologist

Otolaryngologic Clinics of North America

“The endocannabinoid system is located throughout the central and peripheral nervous systems, endocrine system, gastrointestinal system, and within inflammatory cells. The use of medical cannabinoids has been gaining traction as a viable treatment option for varying illnesses in recent years. Research is ongoing looking at the effect of cannabinoids for treatment of common otolaryngologic pathologies. This article identifies common otolaryngologic pathologies where cannabinoids may have benefit, discusses potential drawbacks to cannabinoid use, and suggests future directions for research in the application of medical cannabinoids.”