Diabetic Tidbits
Interesting developments in sugarland
Cannot stay away from endocrinology for too long. It’s in my ‘blood’ after all these years of research and practice. Here are some interesting and surprising findings of late.
Dopamine in the periphery: regulates carbohydrate metabolism
Antipsychotic medications are thought to be centrally acting dopaminergic agents. And a common side effect is weight gain and diabetes. But new info shows that dopamine acts peripherally and directly on the pancreas itself.
At a low concentration, scientists showed, dopamine primarily binds to inhibitory D2-like dopamine receptors and blocks insulin or glucagon release. At high concentrations, however, dopamine also can bind to beta-adrenergic receptors and become stimulatory, pushing hyperglycemic effects of glucagon release in alpha cells while at the same time inhibiting insulin release in beta cells through inhibitory alpha-adrenergic receptors.
Together, these findings finally explain how psychiatric patients develop metabolic syndrome after getting treatment. Blocking inhibitory dopamine receptors with antipsychotics causes a vicious circle—the brake comes off and insulin and glucagon release become unchecked, quickly desensitizing the body and further propagating hyperinsulimia, hyperglycemia and, eventually, obesity and diabetes. - Aslanoglou et al
Are high blood glucose levels an effect rather than the cause of diabetes?
And now we have a chicken versus egg question: is high glucose a biomarker of another different preceding factor? Type 2 diabetics show high levels of a glucose metabolite called methylglyoxal (MG). Study in flies examined the effect of dosing just this metabolite by turning off the enzyme that breaks down MG. Results were consistant with typical type 2 diabetic signs of insulin resistance, high blood glucose levels, and development of obesity.
It appears to be sufficient to increase the MG level to trigger insulin resistance and typical diabetic metabolic disturbances, …This is clear evidence that MG is not the consequence but rather the cause of type 2 diabetes. - Aurelio A. Teleman
Can glycosylated hemoglobin levels predict atherosclerotic disease risk, even in nondiabetics?
Recent research tags the cheap and prevalent diagnostic blood test, Hemoglobin A1c, as a good predictor of future sclerotic vessel disease.
The advance heralded by the CNIC study is the use of this blood-sugar measure in apparently healthy middle-aged individuals who do not have diabetes mellitus but with or without possible prediabetes. When used in combination with traditional risk factors (hypertension, dyslipidemia, and smoking), the glycosylated hemoglobin test more accurately distinguishes between people at high and low risk of atherosclerotic disease. - Xavier Rossello et al
I wonder if it is the MG metabolite that is glycosylating the vessel wall proteins. Obese people, not yet diabetic, do have elevated MG levels.
Now we need to find out - what causes MG to rise?
REFERENCES
https://medicalxpress.com/news/2021-02-dopamine-key-mystery-metabolic-dysfunction.html
Aslanoglou, D., Bertera, S., Sánchez-Soto, M. et al. Dopamine regulates pancreatic glucagon and insulin secretion via adrenergic and dopaminergic receptors. Transl Psychiatry 11, 59 (2021).
Are high blood glucose levels an effect rather than the cause of diabetes? (2018, March 15) https://medicalxpress.com/news/2018-03-high-blood-glucose-effect-diabetes.html
Alexandra Moraru, Janica Wiederstein, Daniel Pfaff, Thomas Fleming, Aubry K. Miller, Peter Nawroth und Aurelio A. Teleman: Elevated Levels of the Reactive Metabolite Methylglyoxal Recapitulate Progression of Type 2 Diabetes, Cell Metabolism 2018, DOI: 10.1016/j.cmet2018.02003
A blood sugar biomarker identifies patients with atherosclerosis and a risk of cardiovascular events (2021, June 1) https://medicalxpress.com/news/2021-06-blood-sugar-biomarker-patients-atherosclerosis.html
Xavier Rossello et al, Glycated Hemoglobin and Subclinical Atherosclerosis in People Without Diabetes, Journal of the American College of Cardiology (2021). DOI: 10.1016/j.jacc.2021.03.335
Please subscribe to my free newsletter by clicking the button. Many future stories will be exclusive to only paid subscribers to BioMedWorks Newsletter: the PREMIUM CONTENT. I would be grateful if you do go on to upgrade to the paid subscription for just $5 a month or $50 a year.
Human clinical trial reveals verapamil as an effective type 1 diabetes therapy
https://medicalxpress.com/news/2018-07-human-clinical-trial-reveals-verapamil.html
https://www.youtube.com/watch?v=4iTUIGMFNyk