A new antipsychotic mechanism of action for cannabidiol

Totally dope! – A new antipsychotic mechanism of action for cannabidiol, by Anand Gururajan

“The pharmacological strategy for the treatment of schizophrenia has not changed in the six decades since chlorpromazine was introduced in 1952. Although several newer agents have recently gained approval, the mechanism of action of antipsychotics is still largely based on normalising dopaminergic neurotransmission which does not adequately address the symptomatology of a very complex disorder. Moreover, they cause side effects such as extrapyramidal motor symptoms and metabolic syndrome which can worsen the patient condition.

In this regard, preclinical and clinical studies since the ’90s have demonstrated the antipsychotic potential of cannabidiol (CBD), a derivative of the cannabis sativa plant which does not have the adverse psychoactive properties of tetrahydrocannabinol.

In particular, CBD has been shown to be effective in attenuating the positive symptoms of schizophrenia with a negligible side-effect profile.

Accumulating evidence implicates dysfunction of the mammalian target of rapamycin (mTOR) signaling cascade in the pathophysiology of schizophrenia. Thus, in a recent paper, Renard et al. (2016) used the amphetamine (AMPH)-sensitisation protocol in rats to investigate whether the antipsychotic effects of CBD were mediated by its effects on the mTOR cascade. Specifically, they focused on the nucleus accumbens shell (NASh) which has been implicated as a therapeutically relevant ‘hot-spot’ for antipsychotic action and is one of the brain regions targeted by CBD.

Thus, together with the fact that CBD alone had no behavioural effects, the behavioural findings reinforce the potential utility of this cannabinoid as an antipsychotic for the treatment of the positive symptoms of schizophrenia.”

http://medicalxpress.com/news/2016-08-antipsychotic-mechanism-action-cannabidiol.html

Cannabigerol is a novel, well-tolerated appetite stimulant in pre-satiated rats.

 

“The appetite-stimulating properties of cannabis are well documented and have been predominantly attributed to the hyperphagic activity of the psychoactive phytocannabinoid, ∆9-tetrahydrocannabinol (∆9-THC).

However, we have previously shown that a cannabis extract devoid of ∆9-THC still stimulates appetite, indicating that other phytocannabinoids also elicit hyperphagia. One possible candidate is the non-psychoactive phytocannabinoid cannabigerol (CBG), which has affinity for several molecular targets with known involvement in the regulation of feeding behaviour.

CBG produced no adverse effects on any parameter in the neuromotor tolerability test battery. In the feeding assay, 120-240 mg/kg CBG more than doubled total food intake and increased the number of meals consumed, and at 240 mg/kg reduced latency to feed. However, the sizes or durations of individual meals were not significantly increased.

CONCLUSIONS:

Here, we demonstrate for the first time that CBG elicits hyperphagia, by reducing latency to feed and increasing meal frequency, without producing negative neuromotor side effects. Investigation of the therapeutic potential of CBG for conditions such as cachexia and other disorders of eating and body weight regulation is thus warranted.”

http://www.ncbi.nlm.nih.gov/pubmed/27503475

Pure Δ9-tetrahydrocannabivarin and a Cannabis sativa extract with high content in Δ9-tetrahydrocannabivarin inhibit nitrite production in murine peritoneal macrophages.

“Historical and scientific evidence suggests that Cannabis use has immunomodulatory and anti-inflammatory effects.

We have here investigated the effect of the non-psychotropic phytocannabinoid Δ9-tetrahydrocannabivarin (THCV) and of a Cannabis sativa extract with high (64.8%) content in THCV (THCV-BDS) on nitric oxide (NO) production, and on cannabinoid and transient receptor potential (TRP) channel expression in lipopolysaccharide (LPS)-stimulated murine peritoneal macrophages.

THCV-BDS and THCV exhibited similar affinity in radioligand binding assays for CB1 and CB2 receptors, and inhibited, via CB2 but not CB1 cannabinoid receptors, nitrite production evoked by LPS in peritoneal macrophages.

THCV down-regulated the over-expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and interleukin 1β (IL-1β) proteins induced by LPS.

Furthermore, THCV counteracted LPS-induced up-regulation of CB1 receptors, without affecting the changes in CB2, TRPV2 or TRPV4 mRNA expression caused by LPS. Other TRP channels, namely, TRPA1, TRPV1, TRPV3 and TRPM8 were poorly expressed or undetectable in both unstimulated and LPS-challenged macrophages.

It is concluded that THCV – via CB2 receptor activation – inhibits nitrite production in macrophages. The effect of this phytocannabinoid was associated with a down-regulation of CB1, but not CB2 or TRP channel mRNA expression.”

http://www.ncbi.nlm.nih.gov/pubmed/27498155

Inhibition of interleukin-8 release in the human colonic epithelial cell line HT-29 by cannabinoids.

 

“We have investigated the effects of cannabinoid agonists and antagonists on tumour necrosis factor-alpha (TNF-alpha)-induced secretion of interleukin-8 from the colonic epithelial cell line, HT-29.

The cannabinoid receptor agonists [(-)-3-[2-hydroxy-4-(1,1-dimethyl-heptyl)-phenyl]4-[3-hydroxypropyl]cyclo-hexan-1-ol] (CP55,940); Delta-9-tetrahydrocannabinol; [R(+)-[2,3-dihydro-5-methyl-3-[(morpholinyl) methyl] pyrrolo[1,2,3-de]1,4-benzoxazin-6-yl](1-naphthyl) methanone mesylate] (WIN55,212-2) and 1-propyl-2-methyl-3-naphthoyl-indole (JWH 015) inhibited TNF-alpha induced release of interleukin-8 in a concentration-dependent manner.

We conclude that in HT-29 cells, TNF-alpha-induced interleukin-8 release is inhibited by cannabinoids through activation of cannabinoid CB(2) receptors.”

http://www.ncbi.nlm.nih.gov/pubmed/12498928

“Essential involvement of interleukin-8 (IL-8) in acute inflammation.”  http://www.ncbi.nlm.nih.gov/pubmed/7964163

“Interleukin-8 (IL-8) is known to possess tumorigenic and proangiogenic properties. Overexpression of IL-8 has been detected in many human tumors, including colorectal cancer (CRC). IL-8 promotes tumor growth, metastasis, chemoresistance and angiogenesis, implying IL-8 to be an important therapeutic target in CRC.”  http://www.ncbi.nlm.nih.gov/pubmed/20648559

Modulation of L-α-lysophosphatidylinositol/GPR55 mitogen-activated protein kinase (MAPK) signaling by cannabinoids.

“This study has implications for developing new therapeutics for the treatment of cancer, pain, and metabolic disorders.

GPR55 is activated by l-α-lysophosphatidylinositol (LPI) but also by certain cannabinoids.

In this study, we investigated the GPR55 pharmacology of various cannabinoids, including analogues of the CB1 receptor antagonist Rimonabant®, CB2 receptor agonists, and Cannabis sativa constituents.

Here, we show that CB1 receptor antagonists can act both as agonists alone and as inhibitors of LPI signaling under the same assay conditions. This study clarifies the controversy surrounding the GPR55-mediated actions of SR141716A; some reports indicate the compound to be an agonist and some report antagonism. In contrast, we report that the CB2 ligand GW405833 behaves as a partial agonist of GPR55 alone and enhances LPI signaling. GPR55 has been implicated in pain transmission, and thus our results suggest that this receptor may be responsible for some of the antinociceptive actions of certain CB2 receptor ligands.

Here, we report that the little investigated cannabis constituents CBDV, CBGA, and CBGV are potent inhibitors of LPI-induced GPR55 signaling.

The phytocannabinoids Δ9-tetrahydrocannabivarin, cannabidivarin, and cannabigerovarin are also potent inhibitors of LPI.

Our findings also suggest that GPR55 may be a new pharmacological target for the following C. sativa constituents: Δ9-THCV, CBDV, CBGA, and CBGV.

These Cannabis sativa constituents may represent novel therapeutics targeting GPR55.”  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3249141/

“Lysophosphatidylinositol (LPI) is a bioactive lipid generated by phospholipase A2 which is believed to play an important role in several diseases.”  http://www.ncbi.nlm.nih.gov/pubmed/22285325

 “The putative cannabinoid receptor GPR55 promotes cancer cell proliferation.  In this issue of Oncogene, two groups demonstrated that GPR55 is expressed in various cancer types in an aggressiveness-related manner, suggesting a novel cancer biomarker and a potential therapeutic target.” http://www.ncbi.nlm.nih.gov/pubmed/21057532
“The orphan G protein-coupled receptor GPR55 promotes cancer cell proliferation via ERK. These findings reveal the importance of GPR55 in human cancer, and suggest that it could constitute a new biomarker and therapeutic target in oncology.” http://www.ncbi.nlm.nih.gov/pubmed/20818416
“The putative cannabinoid receptor GPR55 defines a novel autocrine loop in cancer cell proliferation. These findings may have important implications for LPI as a novel cancer biomarker and for its receptor GPR55 as a potential therapeutic target.”  http://www.ncbi.nlm.nih.gov/pubmed/20838378
“L-α-lysophosphatidylinositol meets GPR55: a deadly relationship. Evidence points to a role of L-α-lysophosphatidylinositol (LPI) in cancer.”  http://www.ncbi.nlm.nih.gov/pubmed/21367464

Endocannabinoid system: Role in depression, reward and pain control (Review).

 

“Depression and pain co-exist in almost 80% of patients and are associated with impaired health-related quality of life, often contributing to high mortality. However, the majority of patients who suffer from the comorbid depression and pain are not responsive to pharmacological treatments that address either pain or depression, making this comorbidity disorder a heavy burden on patients and society.

In ancient times, this depression-pain comorbidity was treated using extracts of the Cannabis sativa plant, known now as marijuana and the mode of action of Δ9‑tetrahydrocannabinol, the active cannabinoid ingredient of marijuana, has only recently become known, with the identification of cannabinoidreceptor type 1 (CB1) and CB2.

Subsequent investigations led to the identification of endocannabinoids, anandamide and 2-arachidonoylglycerol, which exert cannabinomimetic effects through the CB1 and CB2 receptors, which are located on presynaptic membranes in the central nervous system and in peripheral tissues, respectively.

These endocannabinoids are produced from membrane lipids and are lipohilic molecules that are synthesized on demand and are eliminated rapidly after their usage by hydrolyzing enzymes.

Clinical studies revealed altered endocannabinoid signaling in patients with chronic pain.

Considerable evidence suggested the involvement of the endocannabinoid system in eliciting potent effects on neurotransmission, neuroendocrine, and inflammatory processes, which are known to be deranged in depression and chronic pain.

Several synthetic cannabinomimetic drugs are being developed to treat pain and depression. However, the precise mode of action of endocannabinoids on different targets in the body and whether their effects on pain and depression follow the same or different pathways, remains to be determined.”

http://www.ncbi.nlm.nih.gov/pubmed/27484193

Bladder cancer found to be 45% lower in Cannabis users – NCI

National Cancer Institute

“Cannabis has been shown to kill cancer cells in the laboratory” http://www.cancer.gov/about-cancer/treatment/cam/patient/cannabis-pdq

“A review of bladder cancer rates in Cannabis users and non-users was done in over 84,000 men who took part in the California Men’s Health Study. Over 16 years of follow-up and adjusting for age, race/ethnic group and body mass index (BMI), rates of bladder cancer were found to be 45% lower in Cannabis users than in men who did not report Cannabis use.” http://www.cancer.gov/about-cancer/treatment/cam/patient/cannabis-pdq#section/_3

“Association Between Cannabis Use and the Risk of Bladder Cancer: Results From the California Men’s Health Study.”  http://www.ncbi.nlm.nih.gov/pubmed/25623697

Expression of Cannabinoid Receptors in Human Osteoarthritic Cartilage: Implications for Future Therapies

“Cannabinoids have shown to reduce joint damage in animal models of arthritis and reduce matrix metalloproteinase expression in primary human osteoarthritic (OA) chondrocytes.

Chondrocytes from OA joints were shown to express a wide range of cannabinoid receptors even in degenerate tissues, demonstrating that these cells could respond to cannabinoids.

Cannabinoids designed to bind to receptors inhibiting the catabolic and pain pathways within the arthritic joint, while avoiding psychoactive effects, could provide potential arthritis therapies.

Cannabinoids were originally derived from the cannabis plant, Cannabis sativa, which has been used medicinally and recreationally for many years because of its anti-inflammatory, analgesic, and psychoactive properties.”

http://online.liebertpub.com/doi/full/10.1089/can.2015.0001

Preparation and characterization of Δ(9)-tetrahydrocannabinol-loaded biodegradable polymeric microparticles and their antitumoral efficacy on cancer cell lines.

“Cannabinoids present an interesting therapeutic potential as antiemetics, appetite stimulants in debilitating diseases (cancer, AIDS and multiple sclerosis), analgesics, and in the treatment of multiple sclerosis and cancer, among other conditions.

However, despite their high clinical potential, only few dosage forms are available to date.

In this paper, the development of Δ(9)-tetrahydrocannabinol (THC) biodegradable microspheres as an alternative delivery system for cannabinoid parenteral administration is proposed.

As THC has shown therapeutic potential as anticancer drug, the efficacy of the microspheres was tested on different cancer cell lines.

Interestingly, the microspheres were able to inhibit cancer cell proliferation during the nine-day study period.

All the above results suggest that the use of biodegradable microspheres would be a suitable alternative delivery system for THC administration.”

http://www.ncbi.nlm.nih.gov/pubmed/23773072

In vitro and in vivo evaluation of Δ⁹-tetrahidrocannabinol/PLGA nanoparticles for cancer chemotherapy.

“Nanoplatforms can optimize the efficacy and safety of chemotherapy, and thus cancer therapy. However, new approaches are encouraged in developing new nanomedicines against malignant cells.

In this work, a reproducible methodology is described to prepare Δ(9)-tetrahidrocannabinol (Δ(9)-THC)-loaded poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles against lung cancer.

Cell viability studies comparing the activity of the nanoformulations against human A-549 and murine LL2 lung adenocarcinoma cells, and human embryo lung fibroblastic MRC-5 cells revealed a statistically significant selective cytotoxic effect toward the lung cancer cell lines.

In addition, cytotoxicity assays in A-549 cells demonstrated the more intense anticancer activity of Δ(9)-THC-loaded PEGylated PLGA nanoparticles.

These promising results were confirmed by in vivo studies in LL2 lung tumor-bearing immunocompetent C57BL/6 mice.”

http://www.ncbi.nlm.nih.gov/pubmed/25899283