“Background: Ischemia/reperfusion (I/R) is a pivotal mechanism of organ injury during clinical stetting for example for cardiopulmonary bypasses. The generation of reactive oxygen species (ROS) during I/R induces oxidative stress that promotes endothelial dysfunction, DNA dissociation and local inflammation. In turn, those processes induce cytokine release, resulting in damage to cellular structures and cell death. One of the major psychoactive compounds of Cannabis is delta-9-tetrahydrocannabinol (Δ9-THC), which is known as an anti-inflammatory mediator. Our research aimed to test if Δ9-THC may be protective in the treatment of cardiovascular system dysfunction arising from I/R heart injury.

Methods: Two experimental models were used: isolated rat hearts perfused with the Langendorff method and human cardiac myocytes (HCM) culture. Rat hearts and HCM underwent ex vivo/chemical in vitro I/R protocol with/without Δ9-THC treatment. The following parameters were measured: cell metabolic activity, morphology changes, cell damage as lactate dehydrogenase (LDH) activity, ceramide kinase (CERK) activity, ROS level, total antioxidant capacity (TAC) and heart hemodynamic parameters.

Results: Δ9-THC protected the heart, as evidenced by the improved recovery of cardiac function (p < 0.05, N = 3-6). Cells subjected to I/R showed lower cytoplasmic LDH activity, and 10 μM Δ9-THC treatment reduced cell injury and increased LDH content (p = 0.019, N = 6-9). Morphology changes of HCM-spherical shape, vacuolisation of cytoplasm and swollen mitochondria-were inhibited due to Δ9-THC treatment. I/R condition affected cell viability, but 10 μM Δ9-THC decreased the number of dead cells (p = 0.005, N = 6-9). The total level of CERK was lower in the I/R group, reflecting oxidative/nitrosative stress changes. The administration of Δ9-THC effectively increased the production of CERK to the level of aerobic control (p = 0.028, N = 6-9). ROS level was significantly decreased in I/R cells (p = 0.007, N = 6-8), confirming oxidative stress, while administration of 10 μM Δ9-THC enhanced TAC in cardiomyocytes subjected to I/R (p = 0.010, N = 6-8).

Conclusions: Δ9-THC promotes the viability of cardiomyocytes, improves their metabolic activity, decreases cell damage and restores heart mechanical function, serving as a cardioprotective. We proposed the use of Δ9-THC as a cardioprotective drug to be, administered before onset of I/R protocol.”

https://pubmed.ncbi.nlm.nih.gov/35468673/

“Background: Atrial fibrillation, ventricular tachycardia, acute coronary syndromes, and cardiac arrest have been attributed to marijuana. But the National Academy of Science’s 2017 Report, The Health Effects of Cannabis and Cannabinoids, found limited evidence that acute marijuana smoking is positively associated with an increased risk of acute myocardial infarction, and uncovered no evidence to support or refute associations between any chronic effects of marijuana use and increased risk of myocardial infarct (MI).

Aims: We sought to determine the association of marijuana smoking with MI in the UK Biobank cohort. Because red wine is a mood-altering substance, we compared the effect of marijuana with red wine on MI incidence.

Methods: Our analysis included all subjects with MI. The diagnosis was ascertained using the 10^th Revision of the International Classification of Diseases (ICD10 I21). Marijuana was recorded in UKB Category 143, medical conditions, marijuana use. Cigarette smoking information was from UKB Category 100058, smoking. To compare marijuana smoking with the effect of wine drinking we used data from UKB Category 10051, alcohol.

Results: With marijuana use, MI incidence decreased (p < 0.001, two tail Fisher exact test). Red wine was associated with lower MI incidence, although the incidence begins to rise at 11 or more glasses per week (p < 0.001, two tail Fisher exact test). Multivariate analysis was done with logistic regression, MI dependent variable, cigarette pack-years, diabetes type 2, sex, BMI, hypertension, marijuana use, age, red wine consumption, independent variables. Odds ratio (O.R.) 0.844 associated with marijuana use indicates that MI was less likely in marijuana users and was comparable to the effect of red wine (O.R. 0.847).

Conclusion: Marijuana, which has not been shown to have the favorable physiologic effects of red wine on the heart, does reduce MI risk to an extent comparable to red wine. Perhaps both affect the heart by reducing stress.”

https://pubmed.ncbi.nlm.nih.gov/35165641/