Stimulation of the midkine/ALK axis renders glioma cells resistant to cannabinoid antitumoral action

“Δ9-Tetrahydrocannabinol (THC), the major active ingredient of marijuana, and other cannabinoids inhibit tumor growth in animal models of cancer, including glioma, an effect that relies, at least in part, on the stimulation of autophagy-mediated apoptosis in tumor cells. 

…Altogether, our findings identify Mdk as a pivotal factor involved in the resistance of glioma cells to THC pro-autophagic and antitumoral action, and suggest that selective targeting of the Mdk/ALK axis could help to improve the efficacy of antitumoral therapies for gliomas.”

Full text: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3131933/

Stimulation of ALK by the growth factor midkine renders glioma cells resistant to autophagy-mediated cell death

“Δ9-tetrahydrocannabinol (THC), the main active component of marijuana, promotes cancer cell death via autophagy stimulation.

We find that activation of the tyrosine kinase receptor ALK by its ligand midkine interferes with the signaling mechanism by which THC promotes autophagy-mediated glioma cell death.”

 http://www.ncbi.nlm.nih.gov/pubmed/21593591

Biochemical and immunohistochemical changes in delta-9-tetrahydrocannabinol-treated type 2 diabetic rats.

“The regulation of glucose, lipid metabolism and immunoreactivities of insulin and glucagon peptides by delta-9-tetrahydrocannabinol (Δ9-THC) in diabetes were examined in an experimental rat model… 

These results indicate that Δ9-THC may serve a protective role against hyperlipidemia and hyperglycemia in diabetic rats.”

http://www.ncbi.nlm.nih.gov/pubmed/23845579

Antibacterial cannabinoids from Cannabis sativa: a structure-activity study.

Journal of Natural Products

“Marijuana (Cannabis sativa) has long been known to contain antibacterial cannabinoids, whose potential to address antibiotic resistance has not yet been investigated. All five major cannabinoids (cannabidiol (1b), cannabichromene (2), cannabigerol (3b), Delta (9)-tetrahydrocannabinol (4b), and cannabinol (5)) showed potent activity against a variety of methicillin-resistant Staphylococcus aureus (MRSA) strains of current clinical relevance.

Activity was remarkably tolerant to the nature of the prenyl moiety, to its relative position compared to the n-pentyl moiety (abnormal cannabinoids), and to carboxylation of the resorcinyl moiety (pre-cannabinoids). Conversely, methylation and acetylation of the phenolic hydroxyls, esterification of the carboxylic group of pre-cannabinoids, and introduction of a second prenyl moiety were all detrimental for antibacterial activity.

Taken together, these observations suggest that the prenyl moiety of cannabinoids serves mainly as a modulator of lipid affinity for the olivetol core, a per se poorly active antibacterial pharmacophore, while their high potency definitely suggests a specific, but yet elusive, mechanism of activity.” http://www.ncbi.nlm.nih.gov/pubmed/18681481

“Antibacterial Cannabinoids from Cannabis sativa: A Structure−Activity Study”  http://pubs.acs.org/doi/abs/10.1021/np8002673

Antibacterial activity of delta9-tetrahydrocannabinol and cannabidiol.

Image result for Antonie Van Leeuwenhoek. journal

“The minimum inhibiting concentrations (MIC) of delta9-tetrahydrocannabinol (THC) and cannabidiol (CBD) for staphylococci and streptococci in broth are in the range of 1-5 mug/ml.

In the same range, both compounds are also bactericidal.

In media containing 4% serum or 5% blood the antibacterial activity is strongly reduced (MIC 50 mug/ml). Gram-negative bacteria are resistant to THC and CBD.”

http://www.ncbi.nlm.nih.gov/pubmed/1085130

Preparation and characterization of Δ9-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 Δ9-tetrahydrocannabinol (THC) biodegradable microspheres as an alternative delivery system for cannabinoid parenteral administration is proposed. Tetrahydrocannabinol was encapsulated into biodegradable microspheres by the oil-in-water (o/w) emulsion solvent evaporation method. Several formulations were prepared using different drug:polymer ratios. The influence of antioxidant (α-tocopherol acetate) concentration on the release of THC from the microparticles was studied. Elevated process yield and entrapment efficiencies were achieved.The in vitro drug release studies showed that the encapsulated drug was released over a two week period.

 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

Acute Δ9-tetrahydrocannabinol blocks gastric hemorrhages induced by the nonsteroidal anti-inflammatory drug diclofenac sodium in mice.

“Nonsteroidal anti-inflammatory drugs (NSAIDs), which are among the most widely used analgesics in the world, cause gastrointestinal inflammation that is potentially life-threatening.

Although inhibitors of endocannabinoid catabolic enzymes protect against gastropathy in fasted NSAID-treated mice, the gastroprotective effects of Δ9-tetrahydrocannabinol (THC), the primary psychoactive component of marijuana, have yet to be investigated…

 These data indicate that the phytocannabinoid Δ9-THC protects against diclofenac-induced gastric inflammatory tissue damage at doses insufficient to cause common cannabinoid side effects.”

http://www.ncbi.nlm.nih.gov/pubmed/23769745

Synthetic derivatives of THC may weaken HIV-1 infection to enhance antiviral therapies – MedicalXpress

“A new use for compounds related in composition to the active ingredient in marijuana may be on the horizon: a new research report published in the Journal of Leukocyte Biology shows that compounds that stimulate the cannabinoid type 2 (CB2) receptor in white blood cells, specifically macrophages, appear to weaken HIV-1 infection. The CB2 receptor is the molecular link through which the pharmaceutical properties of cannabis are manifested. Diminishing HIV-1 infection in this manner might make current anti-viral therapies more effective and provide some protection against certain HIV-1 complications.

“The synthetic compounds we used in our study may show promise in helping the body fight HIV-1 infection,'” said Yuri Persidsky, M.D., Ph.D., a researcher involved in the work from the Department of Pathology and Laboratory Medicine at Temple University School of Medicine in Philadelphia, PA. “As compounds like these are improved further and made widely available, we will continue to explore their potential to fight other viral diseases that are notoriously difficult to treat.”

To make this discovery, scientists used a cell culture model to infect human macrophages with HIV-1 and added synthetic compounds similar to the active ingredient in marijuana to activate the CB2 receptor. At different times during the infection, samples from the culture were taken to see if the replication of the HIV virus was decreased. The researchers observed diminished HIV growth and a possible protective effect from some HIV-1 complications.

“HIV/AIDS has posed one of the most significant health challenges in modern medicine,” said John Wherry, Ph.D., Deputy Editor of the Journal of Leukocyte Biology. “Recent high profile vaccine failures mean that all options need to be on the table to prevent or treat this devastating infection. Research on the role of cannabinoid type 2 receptors and viral infection may one day allow targeting these receptors to be part of combination therapies that use exploit multiple weaknesses of the virus simultaneously.””

http://medicalxpress.com/news/2013-04-synthetic-derivatives-thc-weaken-hiv-.html

Psychoactive cannabinoids reduce gastrointestinal propulsion and motility in rodents.

“Marijuana has been reported to be an effective antinauseant and antiemetic in patients receiving cancer chemotherapy.

Whether this is due to psychological changes, central antiemetic properties and/or direct effects on gastrointestinal (GI) function is not known. The purpose of these investigations was to determine whether the major constituents of marijuana and the synthetic cannabinoid nabilone have any effects on GI function which can be detected in rodent models of GI transit and motility. Intravenous delta 9-tetrahydrocannabinol (delta 9-THC) slowed the rate of gastric emptying and small intestinal transit in mice and in rats. Delta 9,11-THC, cannabinol and nabilone given i.v. also inhibited small intestinal transit in mice, but were less effective in reducing gastric emptying. Cannabidiol given i.v. had no effect on gastric emptying or intestinal transit. Those cannabinoids which inhibited GI transit did so at doses equal to, or lower, than those reported to produce central nervous system activity. In rats, delta 9-THC produced greater inhibition of gastric emptying and small intestinal transit than large bowel transit, indicating a selectivity for the more proximal sections of the gut. In addition, i.v. delta 9-THC decreased the frequency of both gastric and intestinal contractions without altering intraluminal pressure. Such changes probably reflect a decrease in propulsive activity, without change in basal tone.

These data indicate that delta 9-THC, delta 9,11-THC, cannabinol and nabilone (but not cannabidiol) exert an inhibitory effect on GI transit and motility in rats.”

http://www.ncbi.nlm.nih.gov/pubmed/2542532

Pharmacological synergism between cannabinoids and paclitaxel in gastric cancer cell lines.

“Orally applicable Delta9-tetrahydrocannabinol and its synthetic derivatives have been used as antiemetic drugs during chemotherapy in cancer patients.

 However, it is not well known how cannabinoids influence the effects of chemotherapeutic agents on malignant tumors. In this study, we investigated how the endogenous cannabinoid anandamide (AEA) changes the effect of paclitaxel on gastric cancer cell lines.

 In the human gastric cancer cell line, HGC-27, which express cannabinoid receptor 1 (CB1), AEA stimulated proliferation at concentrations under 1 microM, while it strongly suppressed proliferation through the induction of apoptosis at 10 microM. This bimodal effect was reproduced by a selective CB1 agonist, arachidonyl-2-chloroethylamide, although the effects were less marked. When AEA was used with paclitaxel, AEA at 10 microM synergistically enhanced the cytotoxic effect of paclitaxel, whereas it showed no significant effect at lower concentrations. Flow cytometric analysis revealed that addition of 10 microM AEA synergistically enhanced paclitaxel-induced apoptosis, possibly through the activation of caspase-3, -8, and -9.

Our results suggest that cannabinoids could be a good palliative agent for cancer patients receiving paclitaxel.”

http://www.ncbi.nlm.nih.gov/pubmed/19394652