Micronutrients & Aging
First Time Evidence that Long-Term Magnesium Deficiency Causes Cellular Aging
In an April Procedures of the National Academy of Sciences publication, David Killilea, PhD, and Bruce Ames, PhD, of CHORI’s Center for Nutrition and Metabolism, report on the intriguing results of prolonged moderate magnesium deficiency on human fibroblast cells.
“We wanted to get a better understanding of the consequences of magnesium deficiency on the cell,” says Dr. Killilea.While many studies have assessed the effects of micronutrient deficiency, this is one of the first to investigate the impact of magnesium deficiency in a more real-world model by studying moderate magnesium deficiency on human fibroblast cells over the entire lifespan of those cells.
"Most of the previous cellular and animal studies have only looked at the impact of extreme magnesium deficiency for a short period of time," says Dr. Killilea. "This isn't really reflective of what actually happens in human populations. Most of us have lower than optimal intake, but not none at all."
Unlike cells deprived of all magnesium, which undergo severe stress and die off within a week, the cells in the moderately magnesium deprived medium initially appeared to be relatively healthy and minimally impacted by the lack of magnesium. Further investigation provided some revealing results, however.
"We measured the number of times the cells double, or their replicative capacity, and found it was significantly less in magnesium deficient conditions," Dr. Killilea says.Cell viability wasn't impacted at all, however, which suggested that the cause of the reduced replicating power could be related to cellular senescence, or aging.
"If you're a cell, and you only have 80 percent of a nutrient you need, you'll use that 80 percent for the most important processes you need to get through the day, but to do that, you have to shortchange some other process. While the cells can live with this if they have to, we think the long term consequence is increased cellular aging."
Understanding the underlying mechanism by which magnesium deficiency causes age acceleration requires further exploration. Drs. Killilea and Ames would like to determine what activates the aging process, and why and how magnesium is available for some processes and not others. Nevertheless, the new PNAS study provides significant evidence of the interrelationship between micronutrient deficiency and overall health.
"At least in cell culture lines, moderate but prolonged magnesium deficiency has a consequence," says Dr. Killilea. "The cell can survive, but the long term consequence is that the cell population is not as healthy at the end of its life span."
Whether this translates to the whole animal or human remains to be seen, but in the mean time, Drs. Killilea and Ames will continue to investigate the mechanisms that cause magnesium deprivation to accelerate aging, pursuing the long term goal of understanding what causes aging and aging-related diseases and how simple things like addressing micronutrient deficiency could turn aging-related health decline around.
Tuesday, May 17, 2011 8:19 AM