The metabolic syndrome is a cluster of cardiovascular risk factors, including abdominal obesity, atherogenic dyslipidemia, elevated blood pressure, and insulin resistance, associated with a prothrombotic and proinflammatory state. It is a major health problem in the United States and elsewhere, but we still don't understand its etiology.
Recent studies suggest that endocannabinoids, which are the brain's own marijuana, may be an etiologic factor linked to the metabolic syndrome.[1]
New data show that the human brain makes its own “chemical marijuana” in the form of 2 compounds: anandamide, a Sanskrit word meaning “bliss,” and 2-AG (2-arachidonoylglycerol).[2]
These endocannabinoids are unique since they are synthesized on demand and work in a reverse direction, from postsynaptic neurons where they are synthesized to presynaptic neurons where they bind to receptors.
Two specific endocannabinoid receptors have been identified. These receptors are in high concentrations in the brain, liver, muscle, gut, and adipose tissue. Generally, these receptors appear to be located in areas of the body responsible for modulating energy balance, feeding behavior, hepatic lipogenesis, and glucose homeostasis.[3]
Endocannabinoid stimulation favors metabolic processes that lead to weight gain, lipogenesis, insulin resistance, dyslipidemia, and impaired glucose tolerance, and overactivity of this system has been found in human obesity and in animal models of genetic and diet-induced obesity.
Treatment with a specific endocannabinoid inhibitor, rimonobant, in clinical trials in human obesity has not only reduced excess body weight, but also lowered blood pressure in hypertensive patients, improved insulin sensitivity, corrected dyslipidemia, and decreased the prevalence of metabolic syndrome.[4]
It is remarkable that marijuana components, which have been used for centuries by man, have led to the unfolding story of the effects of endocannabinoids and a possible answer to the metabolic syndrome.
That's my opinion. I'm Dr. George Griffing, Professor of Medicine at St. Louis University and Editor-in-Chief of Internal Medicine for eMedicine.
Footnotes
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References
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