While doing research for an article being featured in print later this year, I’ve accumulated a nice little body of quotes and research regarding the brain, its chemistry and the methods through which cannabis interacts with it- specifically, how cannabis can inspire creativity and thought.
Quotes included are from the abstract and are not meant to stand alone as definitive statements about each study’s conclusions.
3 Studies That Show Cannabis Grows Brain Cells
“The endocannabinoid system has been implicated in the modulation of adult neurogenesis.
Here, we describe the effect of type 1 cannabinoid receptor (CB1R) activation on self-renewal, proliferation and neuronal differentiation in mouse neonatal subventricular zone (SVZ) stem/progenitor cell cultures.
Expression of CB1R was detected in SVZ-derived immature cells (Nestin-positive), neurons and astrocytes.
Stimulation of the CB1R … increased self-renewal of SVZ cells, as assessed by counting the number of secondary neurospheres … Moreover, … treatment for 48 h, increased proliferation …
Surprisingly, stimulation of CB1R … also promoted neuronal differentiation (without affecting glial differentiation), at 7 days, as shown by counting the number of NeuN-positive neurons in the cultures.
Moreover, by … a method that allows the functional evaluation of neuronal differentiation, we observed an increase in neuronal-like cells.
This proneurogenic effect was blocked when SVZ cells were co-incubated with … the CB1R antagonist AM 251, for 7 days, thus indicating that this effect involves CB1R activation.
In accordance with an effect on neuronal differentiation and maturation … also increased neurite growth …
Taken together, these results demonstrate that CB1R activation induces proliferation, self-renewal and neuronal differentiation from mouse neonatal SVZ cell cultures.”
“The hippocampal dentate gyrus in the adult mammalian brain contains neural stem/progenitor cells (NS/PCs) capable of generating new neurons, i.e., neurogenesis.
Most drugs of abuse examined to date decrease adult hippocampal neurogenesis, but the effects of cannabis (marijuana or cannabinoids) on hippocampal neurogenesis remain unknown… cannabinoids could act on CB1 receptors to regulate neurogenesis… suggesting that chronic HU210 treatment produces anxiolytic- and antidepressant-like effects likely via promotion of hippocampal neurogenesis.”
The anxiolytic effect of cannabidiol on chronically stressed mice depends on hippocampal neurogenesis: involvement of the endocannabinoid system
“Cannabidiol (CBD), the main non-psychotomimetic component of the plant Cannabis sativa, exerts therapeutically promising effects on human mental health such as inhibition of psychosis, anxiety and depression. However, the mechanistic bases of CBD action are unclear… CBD administration increased hippocampal anandamide levels… These findings support that the anxiolytic effect of chronic CBD administration in stressed mice depends on its proneurogenic action in the adult hippocampus by facilitating endocannabinoid-mediated signalling.”
Investigating the interaction between schizotypy, divergent thinking and cannabis use
Cannabis acutely increases schizotypy and chronic use is associated with elevated rates of psychosis. Creative individuals have higher levels of schizotypy, however links between cannabis use, schizotypy and creativity have not been investigated. We investigated the effects of cannabis smoked naturalistically on schizotypy and divergent thinking, a measure of creativity… Cannabis increased state psychosis-like symptoms in both groups and the high creativity group were significantly higher in trait schizotypy, but this does not appear to be linked to the verbal fluency change. Acute cannabis use increases divergent thinking as indexed by verbal fluency in low creatives.
Dopamine release in chronic cannabis users: a [11c]raclopride positron emission tomography study.
Low striatal dopamine 2/3 receptor (D(2/3)) availability and low ventrostriatal dopamine (DA) release have been observed in alcoholism and cocaine and heroin dependence. Less is known about the dopaminergic system in cannabis dependence… Cannabis users had an average consumption of 517 ± 465 estimated puffs per month, indicating mild to moderate cannabis dependence. Neither baseline BP(ND) nor ΔBP(ND) differed from control subjects in any region of interest, including ventral striatum. In cannabis-dependent subjects, earlier age of onset of use correlated with lower [ΔBP(ND)] in the associative striatum when controlling for current age. Unlike other addictions, cannabis dependence of mild to moderate severity is not associated with striatal DA alterations.
Dopamine response to psychosocial stress in chronic cannabis users: a PET study with [11C]-+-PHNO.
A number of addictions have been linked with decreased striatal dopamine (DA) receptor availability and DA release. Stress has a key role in cannabis craving, as well as in modulation of dopaminergic signaling… In conclusion, despite an increase in striatal BP(ND) observed during the control task, chronic cannabis use is not associated with alterations in stress-induced DA release.
A Brain on Cannabinoids: The Role of Dopamine Release in Reward Seeking
Increases in mesolimbic dopamine transmission are observed when animals are treated with all known drugs of abuse, including cannabis, and to conditioned stimuli predicting their availability. In contrast, decreases in mesolimbic dopamine function are observed during drug withdrawal, including cannabis-withdrawal syndrome… The recent discovery that endogenous cannabinoids modulate the mesolimbic dopamine system, however, might be exploited for the development of potential pharmacotherapies designed to treat disorders of motivation. Indeed, disrupting endocannabinoid signaling decreases drug-induced increases in dopamine release in addition to dopamine concentrations evoked by conditioned stimuli during reward seeking.
Marijuana Drastically Shrinks Aggressive Form Of Brain Cancer, New Study Finds
“Over the past few years, research has revealed that marijuana can both destroy certain cancer cells and reduce the growth of others. Now, a new study in mice has found that when combined with radiation treatment, cannabis can effectively shrink one of the most aggressive types of brain tumors.
In a paper published Friday in the journal Molecular Cancer Therapies, a team of researchers from St. George’s University of London outlined the “dramatic reductions” they observed in high-grade glioma masses, a deadly form of brain cancer, when treated with a combination of radiation and two different marijuana compounds, also known as cannabinoids. In many cases, those tumors shrunk to as low as one-tenth the sizes of those in the control group.”
Science Shows Marijuana Can Help Kill Tumors, Federal Government Admits
“The information war about marijuana may have turned a new page with the federal government’s acknowledgment of a recent study that found the plant can significantly reduce aggressive types of brain tumors when combined with radiation treatment, endorsing what medicinal marijuana advocates have long affirmed as its healing properties.
A team of researchers from St. George’s University of London recorded reductions in high-grade glioma masses — a deadly form of brain cancer — in mice. The mice’s tumors shrank after they were exposed to radiation in tandem with two marijuana compounds: THC, which creates the “high feeling,” and CBD, which has no psychoactive side effects. In their report, the researchers said that both cannabinoids made tumors more receptive to the radiation treatment, creating what lead author Dr. Wai Lui described to HuffPost as a “triple threat” approach.
“We’ve shown that cannabinoids could play a role in treating one of the most aggressive cancers in adults,” Liu wrote in an op-ed earlier this year. “The results are promising…it could provide a way of breaking through glioma and saving more lives.”
Source: The Compassion Chronicles