CBD Benefits to the Cardiovascular System:
As previously stated, cannabidiol (CBD) has beneficial effects on a wide range of disorders. At iwantmycbd.org, we’ve written about CBD as a potential therapy for Alzheimer’s disease, epilepsy, osteoporosis, arthritis, alcoholism, multiple sclerosis, migraine, irritable bowel disease, and cancer – just to name a few.
But although we’ve touched on the subject before, evidence also suggests that CBD is beneficial in the cardiovascular system as well. This is increasingly important as metabolic syndrome has become epidemic. Metabolic syndrome is typified by high cholesterol, dyslipidemia, hyperglycemia, and hyperinsulinemia. Eventually, hypertension and coronary heart disease develop. However, because of its powerful anti-inflammatory and antioxidant properties, studies have found the cardiovascular system to be a potential therapeutic target for CBD.
A 2013 study published in the British Journal of Clinical Pharmacology by researchers in the U.K. reviewed the research on this subject:
Impaired vasorelaxation is often involved in the pathogenesis of cardiovascular diseases. Numerous studies have shown that endogenous cannabinoids and synthetic cannabinoids cause vasorelaxation (reduction in tension of the blood vessel walls) of a range of animal and human arterial beds. However, plant-derived cannabinoids can induce vasorelaxation as well and several studies have investigated CBD’s vascular effects in animal and human arteries.
For example, a study published in 2003 in the journal Molecular Pharmacology by researchers in the U.S. found that CBD caused a concentration-dependent near maximal vasorelaxation of isolated mesenteric arteries in rats. Although the study did not probe the mechanisms of action, subsequent research published in 2009 in the European Journal of Pharmacology revealed that CBD caused a time-dependent vasorelaxant response by binding to and activating the peroxisome proliferator-activated receptors gamma (PPARγ) receptor. PPARγ regulates fatty acid storage and glucose metabolism by stimulating adipocyte (fat cell) differentiation and lipid metabolism and PPARγ agonists have been shown to have positive cardiovascular effects. The researchers also found that vasorelaxation in the rat isolated aorta appeared to be largely due to calcium channel inhibition.
In another study published in 2015 in Cardiovascular Research, researchers from the U.K. investigated the acute vascular effects of CBD in human arteries and the pharmacology behind the effects. This was the first study of its kind on human arteries and it showed that CBD caused time-dependent vasorelaxation of human mesenteric arteries through the activation of cannabinoid receptor type 1 (CB1) and transient receptor potential (TRP) receptors, and was dependent on endothelium, nitric oxide, and potassium channel modulation. The researchers also discovered that CBD vasorelaxation effects were reduced in males, in patients with type-2 diabetes or hypercholesterolemia (high levels of cholesterol in the blood), and in patients taking statins, beta blockers, and hypoglycaemic medication.
Heart Rate and Blood Pressure
Although researchers have found that CBD doesn’t appear to have any effect on resting blood pressure or heart rate, it does appear to reduce the cardiovascular response to various types of stress.
For example, a number of studies have shown that CBD reduces the cardiovascular response to anxiety or stressful situations. This may be tied to its anxiolytic effects.
One study published in Behaviorial Brain Research in 2006 found that CBD lowered blood pressure and heart rate in Wistar rats in response to conditioned fear. Another study published in the British Journal of Pharmacology in 2009 found that CBD lowered the blood pressure and heart rate of rats in response to acute restraint stress as well.
This could have a significant impact on the development of atherosclerosis and hypertension, which are known to be accelerated by stress.
Numerous studies have shown that CBD has cardioprotective effects which may be through a direct action on the heart or via a general anti-inflammatory / anti-oxidant mechanism. CBD treatment has a protective role in reducing the effects of cardiac ischemia (inadequate blood supply to keep tissue alive) and reperfusion (the damage done when blood flow is restored after a heart attack or stroke), or in reducing cardiac dysfunction associated with diabetes. CBD also has a protective role in reducing the ischemic damage in models of stroke, partly due to maintaining cerebral blood flow.
One study published in Cardiovascular Therapeutics in 2010 found that CBD was protective by reducing the infarct size (an area of dead tissue resulting from failure of blood supply), reduced myocardial inflammation, and improved left ventricular function in rat models of ischemia-reperfusion. Another study published in 2010 in the British Journal of Pharmacology found that acute administration of CBD suppresses ischemia-induced cardiac arrhythmias and reduces infarct size when given at reperfusion. Finally, another 2010 study published in the Journal of the American College of Cardiology showed that CBD reduced cardiac dysfunction, oxidative stress, fibrosis, and inflammatory and cell death signaling pathways in diabetic cardiomyopathy (heart disease).
Endothelial (the inner lining of blood vessels) dysfunction can be broadly defined as an imbalance between vasodilating and vasoconstricting substances produced by (or acting on) the endothelium. Endothelial dysfunction, as defined by a lack of nitric oxide (NO), has been linked to a variety of disease states, including atherosclerosis, diabetes mellitus, coronary artery disease, hypertension, and hypercholesterolemia. However, studies have shown that CBD can combat the negative effects of some conditions (like high glucose levels in diabetes) associated with endothelial dysfunction.
For example, one study showed that CBD lowers high glucose-induced endothelial cell inflammatory response and barrier disruption. Another found that CBD prevented vascular hyperpermeability at the blood−retinal barrier (BRB), and protected the retina against oxidative damage, inflammation and an increase in adhesion molecules. CBD-mediated protection of the vasculature in a model of diabetes may lead to a reduction in complications such as retinopathy. One study also showed that CBD reduced lipopolysaccharide-induced vascular changes and inflammation in the mouse brain as well.
With these studies, CBD has been demonstrated to reduce the negative effects of high glucose, diabetes and inflammation on the vasculature, and on vascular hyperpermeability.
Neuroprotective and Haematological effects (effects on blood physiology)
As discussed previously, CBD provides neuroprotection by regulating Ca2+ homeostasis and can also play a role in restoring damage caused by iron loading in rat models. It also provides neuroprotection in animal and in vitro models of stroke. These neuroprotective effects of CBD are mediated by the ability of CBD to increase cerebral blood flow and reduce vascular hyperpermeability in the brain.
Finally, aside from the effects of CBD on the heart and vasculature, there is evidence that CBD also influences blood cell function as well. Studies have shown that CBD influences both the survival and death of white blood cells, white blood cell migration and platelet aggregation. These actions could possibly help delay or prevent the development of cardiovascular disorders.
As you can see, this review found CBD to have generally positive effects on the cardiovascular system. Although none of the studies conducted were clinical trials, the drug looks extremely promising for a wide range of heart problems. As researchers continue to investigate this subject, CBD may eventually prove to be as beneficial for cardiovascular disease as it does for other adverse health conditions as well.
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