Screening Heart Drugs
Rolf Bodmer, PhD (Professor in the Development and Aging Program of the Sandford-Burnham Medical Institute in La Jolla, California), has been studying genetic and environmental influences on heart function. He has been doing this research primarily on fruit flies.
The heart of a fruit fly is basically a tube with an aorta at the upper end. But the muscular effects of fly heart aging are surprisingly similar to humans. As with humans, exercise-training in fruit flies reduces the age-related decline in heart function.40 Dr. Bodmer’s research team has demonstrated that, as with humans, fruit flies show a decrease in heart rate and an increase in heart arrhythmias (irregular heartbeats) as they age. 41 Dr. Bodmer illustrated these effects at the conference by showing a video of a heart operation in young and old fruit flies. Studying fruit flies has the advantages of short life span, ability to genetically manipulate, and ability to precisely quantify the effects.
Fruit flies fed a high fat diet become obese and display features of metabolic syndrome. Dr. Bodmer’s research team demonstrated that the high fat diet affects the heart independently of atherosclerotic effects by directly impairing heart function.42 Dr. Bodmer suggests that fruit flies could be used for primary screening of drugs to be used against cardiac arrhythmias.43
Reducing Amyloid Formation
Edward Lakatta, MD (Chief of the Laboratory of Cardiovascular Science at the National Institute on Aging in Baltimore, Maryland), has been studying stiffening of arteries close to the heart with aging, a process that leads to an increase in blood pressure. He said that 8 out of 10 older adults develop high blood pressure. He noted that artery stiffness is strongly influenced by collagen, elastin, and other proteins in the artery walls.44 Lakatta has been particularly interested in stiffening of the aorta and upper body by an amyloid fibril protein. Insofar as this form of amyloid is found in the aorta of virtually every Caucasian over the age of 50, this amyloid represents a potential overlooked cause of cardiovascular disease. 45 Dr. Lakatta would like to find ways to reduce amyloid formation in the central arteries as a way of reducing cardiovascular aging.
The Role of Autophagy
Ana Maria Cuervo, MD, PhD (Co-Director of the Einstein Institute of Aging Research at the Albert Einstein College of Medicine in Bronx, New York), was introduced as “the Queen of Autophagy.” Her name appears on sixteen peer-reviewed journal articles about autophagy in 2012 alone.
Autophagy is the most important garbage-collection system used by cells to dispose of cellular waste. Autophagy is the process by which waste is taken to (or taken into) a cell’s lysosome (“incinerator”). From the point of view that the lysosome digests cellular material and recycles (reuses) the breakdown products, the lysosome could also be called the “stomach” of a cell.
More than a decade ago, Dr. Cuervo established that autophagy declines with aging.46 In 2007 she established that age-related autophagy decline is primarily due to changes in the lysosome membrane.47
In her presentation Dr. Cuervo focused on the role that autophagy decline or malfunction plays in neurodegenerative disease. Her team has established that protein malformation in Parkinson’s disease blocks autophagy,48 and that a similar problem occurs in Huntington’s disease49 as well as Alzheimer’s disease.50 They also showed that one of the enzymes that is defective in inherited cases of Alzheimer’s disease is required for effective lysosome function.51 And most recently they showed that a high fat diet or a high cholesterol diet reduces autophagy due to incorporation of those fats into the lysosome membrane.52 Decline in autophagy function could explain the increased risk of Alzheimer’s disease associated with obesity.53
Overall, this conference seemed more concerned with diseases of aging than aging itself, except for the discussion of stem cell rejuvenation and senescent cell action. Nonetheless, chronic inflammation and the effects of fat in aging were recurrent themes. A deep inquiry into the particular conditions revealed the significant roles played by fat and inflammation. Fortunately, Life Extension members have been taking supplements that help suppress chronic inflammation like vitamin D, curcumin, luteolin, DHEA, and omega-3s.
If you have any questions on the scientific content of this article, please call a Life Extension® Health Advisor at 1-866-864-3027.
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