Juvenon Health Journal Vol. 4 No. 5, May 2005
By Benjamin V. Treadwell, Ph.D.
Do you lack energy, or feel tired and physically or mentally unprepared to take on the tasks of the day? This is not unusual, especially as we age, and today’s topic may help explain some of the reasons for this energy deficit.
Two natural compounds produced by our tissues, L-carnitine and acetyl-L-carnitine (ALC), are similar in that both have identical chemical core structures. However, one (ALC) contains an extra component, an acetic acid bound to the core molecule (in what is known as an ester linkage). It turns out that this extra chemical piece makes a significant difference in how this molecule behaves in our body relative to its non-acetylated cousin, L-carnitine. These differences are described below, but first a brief summary of how these molecules normally function in our body.
L-carnitine functions as a vehicle to ferry fat constituents (fatty acids) across a membrane barrier into the cell’s energy-producing machine, the mitochondria, where the fat is converted to energy. Equally important, L-carnitine works in the reverse direction, too. It ferries toxic products produced during fat metabolism out of the mitochondria. This latter step helps maintain the mitochondria as clean-burning, energy-efficient machines.
We are all aware of the fact that as we age, our energy level diminishes. This decrease in energy parallels a decrease in the plasma level of L-carnitine. L-carnitine also decreases under conditions of stress, both psychological and physical. Consequently, it is described as a conditionally essential nutrient. This simply means that when our bodies cannot produce enough of it to meet demand, we need to increase the intake of this nutrient.
Acetyl-L-carnitine is just as active as L-carnitine in transporting fatty acids into the mitochondria. However, as described below, that extra acetyl group confers additional properties to this form of L-carnitine, which make it superior to its non-acetylated cousin.
Both compounds increase energy
Experiments with rats show a dramatic decrease (between 50-70%) in the activity level of old rats as compared to the young animal. Old rats, too, get tired with age! This decrease, as mentioned above, parallels a decrease in the amount of L-carnitine present in the animal’s tissues and blood.
This observation led researchers to investigate whether the old energy-deficient animals could be transformed into more energetic, youthful animals by feeding them a diet enriched with L-carnitine. Supplying L-carnitine to the diet increased the ambulatory activity of the old rats almost two-fold. The experiment was repeated with ALC, and it too increased the animals’ activity level to about an equal degree. So both compounds worked equally well in improving the old rats’ energy levels.
ALC protects the brain
One of the two cousins, ALC, stands out with respect to its effects on the brain and nervous system. First, ALC is more effectively transported into the central nervous system. It more readily traverses the blood-brain barrier – the safety network of blood vessels that separate the brain from the general circulatory system.
ALC, but not L-carnitine, has been demonstrated in animal studies to protect the brain, especially a region involved in short-term memory, the hippocampus, from damage inflicted by toxic oxidants. More specifically, ALC inhibited the production of markers of oxidant-induced tissue damage. This includes damage to cell membrane constituents (lipids), proteins, nucleic acid components of the genetic code (DNA), and molecules generated from the genetic code (mRNA).
These experiments were repeated in animal studies with additional areas of the brain, such as the cortex, with similar results. The quantity of these damaged molecules normally increases with age. This observation supports the hypothesis held by many that aging may be the product of the accumulation of damaged cellular molecules. In animal studies, ALC helped to slow down the rate of accumulated damaged molecules.
ALC may help slow down age-associated cognitive decline. In addition to promoting these positive effects on the cellular constituents of the brain, ALC also may help to increase levels of neurotransmitters. Experiments have demonstrated that the acetic acid group on ALC can be transferred to a molecule known as choline, and convert it to the neurotransmitter, acetylcholine. Acetylcholine is critical for the transmission of impulses in certain nerve cells. A lack of sufficient quantities of this neurotransmitter is associated with aging, and more importantly with impaired memory and mental function. Additional neurotransmitters that may be affected by ALC include glutamate, aspartate and GABA. (Because space is limited, they will not be discussed here.)
ALC’s ability to stimulate neurotransmitters may help explain the observed positive effect of ALC, but not L-carnitine, on cognitive function.
In conclusion, the experimental data from the animal studies described above, and presented in numerous publications, support ALC as having beneficial attributes not shared by L-carnitine.
L-carnitine and acetyl L-carnitine have been extensively researched for many years, in both preclinical and human studies. While the biochemical characteristics of the two amino acids are well established, the absorption and activity of the two substances had never been studied in a head-to-head comparison. Recently a team of researchers from California and Japan compared the effects of the two substances at the same dose in an animal study. Both had positive effects, but ALC was the winner of the face-off. For details, click here.
“Comparison of the Effects of L-Carnitine and Acetyl-L-Carnitine on Carnitine Levels, Ambulatory Activity, and Oxidative Stress Biomarkers in the Brain of Old Rats”
Ann. N.Y. Acad. Sci. 1033: 117–131 (2004).
This Research Update column highlights articles related to recent scientific inquiry into the process of human aging. It is not intended to promote any specific ingredient, regimen, or use and should not be construed as evidence of the safety, effectiveness, or intended uses of the Juvenon product. The Juvenon label should be consulted for intended uses and appropriate directions for use of the product.
I was so impressed with all I’ve read and the results I’ve seen with Juvenon that I bought two for my parents. Then I wondered whether there are any problems with mixing this cellular health supplement with thyroid medication.
My mother had her thyroid killed with radiation and currently takes medication that is working very well. She is 71-years-old and basically in very good health. Will taking Juvenon interact/interfere with her medication?
V.Y., via email
There are many people taking Juvenon who are on medications for hypothyroid conditions. To date there are no reported problems. It is important, however, that your mother continue to have regular checkups to determine blood levels of thyroid hormone (from the drug she takes, as she has a thyroid with reduced activity). I suggest your mother start with oneJuvenon™ Cellular Health tablet per day. She may find that this dose is all she needs. She should take the tablet early in the day for best results, as it can interfere with sleep if taken too late in the day. Of course, it is always a good idea to consult with her health professional regarding the use of dietary supplements with drugs.