Magnesium in the Pathophysiology and Treatment of Hypertension and Diabetes Mellitus: Where Are We in 1997?

T dence of vascular disease? Is there a threshold level of magnesium depletion at which elevated blood pressure or insulin resistance can be expected, or are magnesium levels related to these measurements in a conhe article published in this issue of the American Journal of Hypertension by Paolisso and Barbagallo 1 reviews evidence obtained by these authors and others demonstrating a role for deficiencies of magnesium metabolism in the tinuous, incremental manner? pathophysiology of essential hypertension as well as 4) Finally, can reversing the magnesium deficits of diabetes mellitus, and suggesting the therapeutic found in these conditions actually ameliorate these potential of magnesium supplementation. Considerdiseases or modify their vascular consequences? Is ing the prevalence of these conditions in the general providing extra magnesium to the organism as a population, and of their overriding importance as facwhole by oral-nutritional supplementation effective, tors predisposing to atherosclerotic cardiovascular or sufficient, in reversing the magnesium or clinical disease, it is important to ascertain more precisely: abnormalities? As of 1997, while the answers to the above questions 1) What does magnesium have to do with these are only incompletely known, a link between magneapparently different, but often clinically coincident, sium, diabetes mellitus, and hypertension seems esconditions? How definitive can we be at this stage tablished beyond a reasonable doubt, and this should that altered magnesium metabolism actually contrinow be appreciated outside of the narrow confines of butes to either or both of these conditions, rather than magnesium research laboratories by the wider audirepresenting an epiphenomenal marker of them? ence of clinicians treating these conditions. Magne2) What diagnostic tools are available to define the sium intake is an independent predictor of blood presmagnesium ‘‘status’’ of subjects that might identify sure and the prevalence of hypertension in large popsubjects suffering from these conditions, or those with ulations, often more significantly related to disease positive family histories or with other factors predisrisk than other mineral elements, such as sodium and posing them to hypertension, diabetes mellitus, and calcium. At the biochemical level, magnesium dithe vascular disease attendant to these syndromes? rectly regulates cellular glucose metabolism, peptide Are these techniques ready for widespread clinical hormone receptor signal transduction, stimulus-conapplication? traction coupling, stimulus-secretion coupling, and 3) What quantitative degree of deviation from avion channel translocation. This is because of its role erage normal values confers a significantly increased as part of the activated MgATP complex required for risk of expressing these conditions or preclinical eviall of the rate-limiting enzymes of glycolysis, the activity of all protein kinases, and more generally, all ATP and phosphate transfer-associated enzymes, Received December 19, 1996. Accepted December 19, 1996. such as the CaATPases in plasma membrane and enFrom the Division of Endocrinology and Hypertension, Wayne doplasmic reticulum. Significant decrements in these State University Medical Center, Detroit, Michigan. Address correspondence and reprint requests to Lawrence M. enzyme activities can already be observed at the range Resnick, MD, Division of Endocrinology/Hypertension, Wayne of magnesium values seen in disease states such as State University Medical Center, 4201 St. Antoine, UHC-4H, Detroit, MI 48201. diabetes mellitus and hypertension. Consistent with