CB1 cannabinoid receptor induction in experimental stroke.

“Cannabinoids protect cortical neurons from ischemic injury by interacting with CB1 receptors. Because a variety of neuroprotective genes are induced in cerebral ischemia, we examined the effect of experimental stroke, produced by 20 minutes of middle cerebral artery occlusion in rats, on CB1 receptor expression.

Western blotting and immunohistochemistry showed that CB1 expression on neurons was increased in the arterial boundary zone of the cortical mantle, beginning by 2 hours and persisting for 72 hours or more after ischemia.

These findings are consistent with a neuroprotective role for endogenous cannabinoid signaling pathways and with a potential therapeutic role in stroke for drugs that activate CB1 receptors.”

http://www.ncbi.nlm.nih.gov/pubmed/10939579

Endocannabinoids and obesity.

“A safe and effective antiobesity drug is needed to combat the global obesity epidemic. The discovery of cannabinoids from medicinal herbs has revealed the endocannabinoid system (ECS) in animals and humans, which regulates various physiological activities such as feeding, thermogenesis, and body weight (BW).

Although cannabinoid receptors 1 (CB1) antagonists have shown antiobesity efficacies in animal models and in the clinic, they failed to establish as a treatment due to their psychological side effects.

 Recent studies indicate that CB1 in various peripheral tissues may mediate some of the therapeutic effects of CB1 antagonists, such as improved lipid and glucose homeostasis.

 It rationalizes the development of compounds with limited brain penetration, for minimizing the side effects while retaining the therapeutic efficacies. A survey of the literature has revealed some controversies about how the ECS affects obesity. This review summarizes the research progresses and discusses some future perspectives.”

http://www.ncbi.nlm.nih.gov/pubmed/23374723

Cannabinoid receptors as novel targets for the treatment of melanoma

“Melanoma causes the greatest number of skin cancer-related deaths worldwide. Here, we evaluated the efficacy of cannabinoid receptor agonists, a new family of potential antitumoral compounds, at skin melanoma. Human melanomas and melanoma cell lines express CB1 and CB2 cannabinoid receptors. Activation of these receptors decreased growth, proliferation, angiogenesis and metastasis, and increased apoptosis, of melanomas in mice. Cannabinoid antimelanoma activity was independent of the immune status of the animal, could be achieved without overt psychoactive effects and was selective for melanoma cells vs. normal melanocytes.

Cannabinoid antiproliferative action on melanoma cells…

 These findings may contribute to the design of new chemotherapeutic strategies for the management of melanoma.

 …the present report, together with the implication of CB2 receptors in the control of processes such as pain initiation, emesis, and inflammation, opens the attractive possibility of finding cannabinoid-based therapeutic strategies devoid of nondesired psychotropic side effects.

Specifically, the antiproliferative effect of cannabinoids reported here may set the basis for a new therapeutic approach for the treatment of malignant melanoma.”

Full text: http://www.fasebj.org/content/20/14/2633.long

Inhibition of skin tumor growth and angiogenesis in vivo by activation of cannabinoid receptors

“Cannabinoids inhibit skin tumor growth in vivo. Here we show that the CB1 and the CB2 receptor are expressed in normal skin and skin tumors of mice and humans. In cell culture experiments pharmacological activation of cannabinoid receptors induced the apoptotic death of tumorigenic epidermal cells, whereas the viability of nontransformed epidermal cells remained unaffected. Local administration of the mixed CB1/CB2 agonist WIN-55,212-2 or the selective CB2 agonist JWH-133 induced a considerable growth inhibition of malignant tumors generated by inoculation of epidermal tumor cells into nude mice. Cannabinoid-treated tumors showed an increased number of apoptotic cells.

 

Cannabinoids, the active components of Cannabis sativa linnaeus (marijuana)…

Marijuana and its derivatives have been used in medicine for many centuries, and currently there is a renaissance in the study of the therapeutic effects of cannabinoids… cannabinoids may be potential antitumoral agents owing to their ability to induce the regression of various types of tumors, including lung adenocarcinoma, glioma, and thyroid epithelioma in animal models.

This background prompted us to explore whether (a) the skin and skin tumors express cannabinoid receptors; (b) cannabinoid receptor activation exerts a growth-inhibiting action on skin tumors in vivo; and (c) inhibition of angiogenesis is implicated in the anti-tumoral effect of cannabinoids.

Our data show that (a) CB1 and CB2 receptors are present in the skin and skin tumors; (b) local cannabinoid receptor activation induces the regression of skin tumors in vivo; and (c) at least two mechanisms may be involved in this action: direct apoptosis of tumor cells and inhibition of tumor angiogenesis.

These results support a new therapeutic approach for the treatment of skin tumors.”

Full text: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC151833/

Revisiting CB1 receptor as drug target in human melanoma.

“Previous studies have indicated the antitumoral effect of human melanocytes, human melanoma cell lines expressing CB1 receptor (CB1), and of the peritumoral administration of endocannabinoids. In the present study, we systematically screened several human melanoma cell lines for the expression of CNR1 and demonstrated transcription of the authentic gene. The product of CNR1, the CB1 protein, was found localized to the cell membrane as well as to the cytoskeleton. Further, the studied human melanoma cell lines expressed functional CB1 since physiological and synthetic ligands, anandamide (AEA), Met-F-AEA, ACEA and AM251 showed a wide range of biological effects in vitro, for example anti-proliferative, proapoptotic and anti-migratory. More importantly, our studies revealed that systemic administration of a stable CB1 agonist, ACEA, into SCID mice specifically inhibited liver colonization of human melanoma cells.

Since therapeutic options for melanoma patients are still very limited, the endocannabinoid-CB1 receptor system may offer a novel target.”

http://www.ncbi.nlm.nih.gov/pubmed/22447182

The endocannabinoid system of the skin in health and disease: novel perspectives and therapeutic opportunities

“The endocannabinoid system (ECS) and the skin. Recent studies have intriguingly suggested the existence of a functional ECS in the skin and implicated it in various biological processes. It seems that the main physiological function of the cutaneous ECS is to constitutively control the proper and well-balanced proliferation, differentiation and survival, as well as immune competence and/or tolerance, of skin cells. The disruption of this delicate balance might facilitate the development of multiple pathological conditions and diseases of the skin (e.g. acne, seborrhea, allergic dermatitis, itch and pain, psoriasis, hair growth disorders, systemic sclerosis and cancer).

Perspectives in the ECS-targeted management of skin diseases

… preclinical data encourage one to systematically explore whether ECS-modulating drugs can be exploited in the management of common skin disorders…

 … we review preliminary data and discuss the possible applications of ECS-targeted therapies…ECS-targeted approaches in skin diseases. Modulations of the fine-tuned tone of the cutaneous endocannabinoid system (ECS) could have therapeutic values in the management of a large variety of human skin diseases…

Conclusions and future directions in experimental and clinical research

… it is envisaged (this is also strongly supported by pilot studies) that the targeted manipulation of the ECS might be beneficial in a multitude of human skin diseases. However, to predict the real therapeutic potential and translate the exciting preclinical observations discussed earlier into clinical practice, numerous important questions should carefully be addressed. Nevertheless, targeting the cutaneous ECS for therapeutic gain remains an intriguing and provocative possibility warranting future studies.”

Full text: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2757311/

The association of N-palmitoylethanolamine with the FAAH inhibitor URB597 impairs melanoma growth through a supra-additive action.

“The incidence of melanoma is considerably increasing worldwide. Frequent failing of classical treatments led to development of novel therapeutic strategies aiming at managing advanced forms of this skin cancer. Additionally, the implication of the endocannabinoid system in malignancy is actively investigated…

CONCLUSIONS:

This study suggests the interest of targeting the endocannabinoid system in the management of skin cancer and underlines the advantage of associating endocannabinoids with enzymatic hydrolysis inhibitors.

This may contribute to the improvement of long-term palliation or cure of melanoma.”

Full text: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3364151/

Cannabidiol Inhibits Growth and Induces Programmed Cell Death in Kaposi Sarcoma–Associated Herpesvirus-Infected Endothelium

“Kaposi sarcoma is the most common neoplasm caused by Kaposi sarcoma–associated herpesvirus (KSHV). Current treatments for Kaposi sarcoma can inhibit tumor growth but are not able to eliminate KSHV from the host. When the host’s immune system weakens, KSHV begins to replicate again, and active tumor growth ensues. New therapeutic approaches are needed.

Cannabidiol (CBD), a plant-derived cannabinoid, exhibits promising antitumor effects without inducing psychoactive side effects. CBD is emerging as a novel therapeutic for various disorders, including cancer.

In this study, we investigated the effects of CBD both on the infection of endothelial cells (ECs) by KSHV and on the growth and apoptosis of KSHV-infected ECs, an in vitro model for the transformation of normal endothelium to Kaposi sarcoma….

Cannabidiol (CBD) was first isolated in 1940. It is a major component of the plant Cannabis sativa, which is also the source of Δ9-tetrahydrocannabinol (Δ9-THC). Due to its multiple biological activities, CBD has been identified as a potential clinical agent. Moreover, CBD affects these activities without the psychoactive side effects that typify Δ9-THC. Recent studies have documented the potential antitumorigenic properties of CBD in the treatment of various neoplasms, including breast cancer, lung cancer, bladder cancer, glioblastoma,and leukemia.CBD induces these effects through a variety of mechanisms and signaling pathways

CBD has been evaluated clinically for the treatment of various conditions, including anxiety, psychosis, and pain. In contrast to other members of the cannabinoid family, CBD has a strong safety profile and induces no psychotropic effects.Therefore, it has become an attractive agent in the search for new anticancer therapies.Our current study demonstrated that CBD preferentially enhanced apoptosis and inhibited the proliferation of KSHV-infected endothelial cells. This selective targeting of KSHV-induced neoplasia suggests that CBD may have a desirable therapeutic index when used to treat cancer. Moreover, a recent study demonstrated that CBD can be delivered effectively by nasal and transdermal routes, which may be particularly valuable for the treatment of Kaposi sarcoma oral or skin lesions.”

Full text: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3527984/

Cannabidiol Relieves Psychosis in Schizophrenia, Why is it Illegal?

“A molecule in cannabis (CBD) has shown to relieve anxiety and symptoms of psychosis in people diagnosed with schizophrenia, though many patients are denied or discouraged from this medicine with fewer side effects than pharmaceutical products because the DEA has deemed the cannabis plant to be “illegal”. The U.S. government needs to answer “why?” this medicine warrents time in prison when nobody is being harmed.

 Investigators concluded, “Our results provide evidence that the non-cannabimimetic constituent of marijuana, cannabidiol, exerts clinically relevant antipsychotic effects that are associated with marked tolerability and safety, when compared with current medications. … The results … potentially represent a completely new mechanism in the treatment of schizophrenia.”

 “Studies have suggested a wide range of possible therapeutic effects of cannabidiol on several conditions, including Parkinson’s disease, Alzheimer’s disease, cerebral ischemia, diabetes, rheumatoid arthritis, other inflammatory diseases, nausea and cancer,” Zuardi writes. Let’s look at a few of these in detail, shall we?

1. Antiepileptic action
“In 1973, a Brazilian group reported that CBD was active in … blocking convulsions produced in experimental animals.”

2. Sedative action
“In humans with insomnia, high doses of CBD increased sleep duration compared to placebo.”

3. Anxiolytic action
“CBD induce[s] a clear anxiolytic effect and a pattern of cerebral activity compatible with an anxiolytic activity.”

4. Antipsychcotic action
“[C]linical studies suggest that CBD is an effective, safe and well-tolerated alternative treatment for schizophrenic patients.”

5. Antidystonic action
“CBD … had antidystonic effects in humans when administered along with standard medication to five patients with dystonia, in an open study.”

6. Antioxidative action
“[I]t was demonstrated that CBD can reduce hydroperoxide-induced oxidative damage as well as or better than other antioxidants. CBD was more protective against glutamate neurotoxicity than either ascorbate or a-tocopherol, indicating that this drug is a potent antioxidant.”

7. Neuroprotective action
“A marked reduction in the cell survival was observed following exposure of cultured rat pheochromocytoma PC12 cells to beta-A peptide. Treatment of the cells with CBD prior to beta-A exposure significantly elevated the cell survival.”

8. Antiinflammatory action
“CBD, administered i.p. or orally, has blocked the progression of arthritis.”

9. Cardioprotective action
“CBD induces a substantial cardioprotective effect.”

10. Action on diabetes
“CBD treatment of NOD (non-obese diabetic) mice before the development of the disease reduced its incidence from 86% in the non-treated control mice to 30% in CBD-treated mice. … It was also observed that administration of CBD to 11-14 week old female NOD mice, which were either in a latent diabetes stage or had initial symptoms of diabetes, ameliorated the manifestations of the disease.”

11. Antiemetic action
“The expression of this conditioned retching reaction was completely suppressed by CBD and delta9-THC, but not by ondansetron, [an] antagonist that interferes with acute vomiting.”

12. Anticancer action
“A study of the effect of different cannabinoids on eight tumor cell lines, in vitro, has clearly indicated that, of the five natural compounds tested, CBD was the most potent inhibitor of cancer cell growth.”

In sum, the past 45 years of scientific study on CBD has revealed the compound to be non-toxic, non-psychoactive, and to possess a multitude of therapeutic properties. Yet, to this day it remains illegal to possess or use (and nearly impossible to study in US clinical trials) simply because it is associated with marijuana.

What possible advancements in medical treatment may have been achieved over the past decades had US government officials chosen to advance — rather than inhibit — clinical research into CBD (which, under federal law, remains a Schedule I drug defined as having “no currently accepted medical use”)? Perhaps it’s time someone asks John Walters or the DEA?” 

Read more: http://rinf.com/alt-news/latest-news/cannabidiol-relieves-psychosis-in-schizophrenia-why-is-it-illegal/17827/

Cannabinoids Halt Pancreatic Cancer, Breast Cancer Growth, Studies Say

“Compounds in cannabis inhibit cancer cell growth in human breast cancer cell lines and in pancreatic tumor cell lines, according to a pair of preclinical trials published in the July issue of the journal of the American Association for Cancer Research.

In one trial, investigators at Complutense University in Spain and the Institut National de la Sante et de la Recherche Medicale (INSERM) in France assessed the anti-cancer activity of cannabinoids in pancreatic cancer cell lines and in animals. Cannabinoid administration selectively increased apoptosis (programmed cell death) in pancreatic tumor cells while ignoring healthy cells, researchers found. In addition, “cannabinoid treatment inhibited the spreading of pancreatic tumor cells … and reduced the growth of tumor cells” in animals.

“These findings may contribute to … a new therapeutic approach for the treatment of pancreatic cancer,” authors concluded.

In the second trial, investigators at Spain’s Complutense University reported that THC administration “reduces human breast cancer cell proliferation [in vitro] by blocking the progression of the cell cycle and by inducing apoptosis.” Authors concluded that their findings “may set the bases for a cannabinoid therapy for the management of breast cancer.”

Previous preclinical data published in May in the Journal of Pharmacological and Experimental Therapeutics reported that non-psychoactive cannabinoids, particularly cannabidiol (CBD), dramatically halt the spread of breast cancer cells and recommended their use in cancer therapy.

Separate trials have also shown cannabinoids to reduce the size and halt the spread of glioma (brain tumor) cells in animals and humans in a dose dependent manner. Additional preclinical studies have demonstrated cannabinoids to inhibit cancer cell growth and selectively trigger malignant cell death in skin cancer cells, leukemic cells, lung cancer cells, and prostate carcinoma cells, among other cancerous cell lines.”

http://norml.org/news/2006/07/06/cannabinoids-halt-pancreatic-cancer-breast-cancer-growth-studies-say