Tag Archives: therapies

Peripherally restricted CB1 receptor blockers.

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“Antagonists (inverse agonists) of the cannabinoid-1 (CB1) receptor showed promise as new therapies for controlling obesity and related metabolic function/liver disease.

These agents, representing diverse chemical series, shared the property of brain penetration due to the initial belief that therapeutic benefit was mainly based on brain receptor interaction. However, undesirable CNS-based side effects of the only marketed agent in this class, rimonabant, led to its removal, and termination of the development of other clinical candidates soon followed. Re-evaluation of this approach has focused on neutral or peripherally restricted (PR) antagonists.

Supporting these strategies, pharmacological evidence indicates most if not all of the properties of globally acting agents may be captured by molecules with little brain presence. Methodology that can be used to eliminate BBB penetration and the means (in vitro assays, tissue distribution and receptor occupancy determinations, behavioral paradigms) to identify potential agents with little brain presence is discussed.

Focus will be on the pharmacology supporting the contention that reported agents are truly peripherally restricted. Notable examples of these types of compounds are: TM38837 (structure not disclosed); AM6545 (8); JD5037 (15b); RTI-12 (19).”

http://www.ncbi.nlm.nih.gov/pubmed/23902803

Marijuana Ingredient Inhibits VEGF Pathway Required For Brain Tumor Blood Vessels

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“Cannabinoids, the active ingredients in marijuana, restrict the sprouting of blood vessels to brain tumors by inhibiting the expression of genes needed for the production of vascular endothelial growth factor (VEGF).

“Blockade of the VEGF pathway constitutes one of the most promising antitumoral approaches currently available,” said Manuel Guzmán, professor of biochemistry and molecular biology, with the Complutense University in Madrid, Spain, and the study’s principal investigator.

“The present findings provide a novel pharmacological target for cannabinoid-based therapies.””

More: http://www.sciencedaily.com/releases/2004/08/040816085401.htm

“Cannabinoids inhibit the vascular endothelial growth factor pathway in gliomas.” http://cancerres.aacrjournals.org/content/64/16/5617.long

CB1 agonists, locally applied to the cortico-thalamic circuit of rats with genetic absence epilepsy, reduce epileptic manifestations.

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“Drugs that modulate the endocannabinoid system and endocannabinoids typically play an anticonvulsant role although some proconvulsant effects have been reported both in humans and animal models.

 This study aims to characterize the role of cannabinoids in specific areas of the cortico-thalamic network involved in oscillations that underlie seizures in a genetic animal model of absence epilepsy, the WAG/Rij rat.

These results, together with previous reports, support therapeutic potential for endocannabinoid system modulators in absence epilepsy and highlight that attenuated endocannabinergic function may contribute to the generation and maintenance of seizures. Furthermore, the entire cortico-thalamic network responds to cannabinoid treatment, indicating that in all areas considered, CB receptor activation inhibits the pathological synchronization that subserves absence seizures.

 In conclusion, our result might be useful for the identification of future drug therapies in absence epilepsy.”

http://www.ncbi.nlm.nih.gov/pubmed/23860329

Amphiregulin is a factor for resistance of glioma cells to cannabinoid-induced apoptosis.

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“Gliomas, one of the most malignant forms of cancer, exhibit high resistance to conventional therapies. Identification of the molecular mechanisms responsible for this resistance is therefore of great interest to improve the efficacy of the treatments against these tumors. Delta9-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 ability of these compounds to induce apoptosis of tumor cells.

…we identified the epidermal growth factor receptor ligand amphiregulin as a candidate factor to mediate the resistance of glioma cells to cannabinoid treatment… in vivo silencing of amphiregulin rendered the resistant tumors xenografts sensitive to cannabinoid antitumoral action.

Amphiregulin expression was associated with increased extracellular signal-regulated kinase (ERK) activation, which mediated the resistance to THC by blunting the expression of p8 and TRB3-two genes involved in cannabinoid-induced apoptosis of glioma cells.

 Our findings therefore identify Amphirregulin as a factor for resistance of glioma cells to THC-induced apoptosis and contribute to unraveling the molecular bases underlying the emerging notion that targeted inhibition of the EGFR pathway can improve the efficacy of antitumoral therapies.”

http://www.ncbi.nlm.nih.gov/pubmed/19229996

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

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“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/

Human Immunodeficiency Virus In Late-Stage AIDS Inhibited By Marijuana-Like Chemicals – MedicalNewsToday

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“Mount Sinai School of Medicine researchers have discovered that marijuana-like chemicals trigger receptors on human immune cells that can directly inhibit a type of human immunodeficiency virus (HIV) found in late-stage AIDS, according to new findings published online in the journal PLoS ONE.

Medical marijuana is prescribed to treat pain, debilitating weight loss and appetite suppression, side effects that are common in advanced AIDS. This is the first study to reveal how the marijuana receptors found on immune cells – called cannabinoid receptors CB1 and CB2 – can influence the spread of the virus. Understanding the effect of these receptors on the virus could help scientists develop new drugs to slow the progression of AIDS.

“We knew that cannabinoid drugs like marijuana can have a therapeutic effect in AIDS patients, but did not understand how they influence the spread of the virus itself,” said study author Cristina Costantino, PhD, Postdoctoral Fellow in the Department of Pharmacology and Systems Therapeutics at Mount Sinai School of Medicine. “We wanted to explore cannabinoid receptors as a target for pharmaceutical interventions that treat the symptoms of late-stage AIDS and prevent further progression of the disease without the undesirable side effects of medical marijuana.”

HIV infects active immune cells that carry the viral receptor CD4, which makes these cells unable to fight off the infection. In order to spread, the virus requires that “resting” immune cells be activated. In advanced AIDS, HIV mutates so it can infect these resting cells, gaining entry into the cell by using a signaling receptor called CXCR4. By treating the cells with a cannabinoid agonist that triggers CB2, Dr. Costantino and the Mount Sinai team found that CB2 blocked the signaling process, and suppressed infection in resting immune cells.

Triggering CB1 causes the drug high associated with marijuana, making it undesirable for physicians to prescribe. The researchers wanted to explore therapies that would target CB2 only. The Mount Sinai team infected healthy immune cells with HIV, then treated them with a chemical that triggers CB2 called an agonist. They found that the drug reduced the infection of the remaining cells.

“Developing a drug that triggers only CB2 as an adjunctive treatment to standard antiviral medication may help alleviate the symptoms of late-stage AIDS and prevent the virus from spreading,” said Dr. Costantino. Because HIV does not use CXCR4 to enhance immune cell infection in the early stages of infection, CB2 agonists appear to be an effective antiviral drug only in late-stage disease.

As a result of this discovery, the research team led by Benjamin Chen, MD, PhD, Associate Professor of Infectious Diseases, and Lakshmi Devi, PhD, Professor of Pharmacology and Systems Therapeutics at Mount Sinai School of Medicine, plans to develop a mouse model of late-stage AIDS in order to test the efficacy of a drug that triggers CB2 in vivo. In 2009 Dr. Chen was part of a team that captured on video for the first time the transfer of HIV from infected T-cells to uninfected T-cells.”

http://www.medicalnewstoday.com/releases/243183.php

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

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“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

Scientists weaken HIV infection in immune cells using synthetic agents – MedicalXpress

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“HIV, the virus that causes AIDS, is notorious for hiding within certain types of cells, where it reproduces at a slowed rate and eventually gives rise to chronic inflammation, despite drug therapy. But researchers at Temple University School of Medicine’s Department of Pathology and Laboratory Medicine and Center for Substance Abuse Research (CSAR) recently discovered that synthetic anti-inflammatory substances distantly related to the active ingredient of marijuana may be able to take the punch out of HIV while inside one of its major hideouts – immune cells known as macrophages.

The results suggest that selective CB2 agonists could potentially be used in tandem with existing antiretroviral drugs, opening the door to the generation of new drug therapies for HIV/AIDS. The data also support the idea that the human immune system could be leveraged to fight HIV infection.

“Our study suggests that the body’s own natural defenses can be made more powerful to fight some of the worst symptoms of HIV,” Persidsky explained. He also noted that stimulating CB2 receptors in white blood cells could produce similar benefits against other viral infections.

 The most promising compounds are those derived from THC (tetrahydrocannabinol), the main active substance in cannabis.”

More: http://medicalxpress.com/news/2013-05-scientists-weaken-hiv-infection-immune.html

Marijuana Study Shows Brain Cancer Cells Eat Themselves

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“… a study released by researchers at the Complutense University in Madrid describes how marijuana’s active chemical, tetrahydrocannabinol, can aid anti-cancer therapies due to its ability to coax cancerous brain cells to self-digest.

The research involved stimulating cancer growth in mice and then injecting sites near the tumors with THC every day. An experimental trial involving two brain cancer patients were also analyzed by the researchers.

It studied how an aggressive brain tumor type was affected by THC, noting that the findings fell in line with the tests done on mice. They say the work shows how “a new family of potential antitumoral agent” exists among THC and related cannabinoids.”

http://www.shortnews.com/start.cfm?id=78020

“Cannabinoid action induces autophagy-mediated cell death through stimulation of ER stress in human glioma cells”

Full Text: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2673842/

Cannabis Linked to Decreased Bladder Cancer Risk

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“The use of cannabis among men has been linked to a significantly decreased risk for bladder cancer, according to a recent study; however, no cause and effect association has been found.”

“The study, presented at the AUA 2013 Annual Meeting, found that men who reported using cannabis had a 45% lower risk for developing bladder cancer compared with men who did not smoke, even after adjusting for age, BMI, and race/ethnicity.

“Bladder cancer is one of the most prevalent genitourinary malignancies with an estimated 72,570 new cases and 15,210 cancer-related deaths per year in the United States, and it is the fourth most common malignancy in men,” Anil Thomas, MD, study author and endourology fellow at Kaiser Permanente Los Angeles Medical Center, said in an e-mail communication. “Importantly, advanced bladder cancer is inherently challenging to treat due to its associated high mortality and lack of effective systemic therapies.””

More: http://www.cancernetwork.com/genitourinary-cancer/content/article/10165/2144158

“Association Between Cannabis Use and the Risk of Bladder Cancer: Results From the California Men’s Health Study… using tobacco only was associated with an increased risk of bladder cancer, whereas cannabis use only was associated with a 45% reduction in bladder cancer… cannabis use may be inversely associated with bladder cancer risk…”  http://www.ncbi.nlm.nih.gov/pubmed/25623697

http://www.thctotalhealthcare.com/category/bladder-cancer/