How The Aging Clock Works

Melatonin is the pacemaker for the circadian rhythms that maintain our health, strength, and youthful vigor through the neuroendocrine and immunologic control of vital functions such as sleep, appetite, heart rate, blood pressure, temperature, movement, coordination, pain and pleasure, sexual function, reproduction, and protection against invading bacteria, viruses, chemicals, and radiation.

Melatonin is the clock that governs the actions of the hypothalamus region of the brain, which produces releasing factors that trigger the pituitary gland to release peptide hormones such as prolactin and growth hormone which, in turn, stimulate the release of thyroid hormones, adrenal hormones such as DHEA and cortisol, and steroid hormones from the testes and ovaries such as testosterone, estrogen, and progesterone.

The healthy functioning of this intricate system requires a synchronized, rhythmic, cascading ebb-and-flow involving highly sensitive interactions among the neurotransmitters, hormones, and enzymes that affect every organ and life system in the body. A good example of the circulatory, cascading nature of the system is the fact that estrogen is produced by the ovaries after a long series of signals or messages starting in the brain. After its release, estrogen travels throughout the body to help maintain strength and vigor and, finally, ends up in the brain, where it helps to maintain memory and other cognitive functions in the process of starting the cycle over again.

Sending Messages From One Cell To Another

In governing this system, melatonin acts as a neurotransmitter to help control the activity of neurons in the central nervous system. It does so by sending chemical messages via cyclic nucleotides such as cyclic AMP (cAMP) and cyclic GMP (cGMP) which travel from one neuron to another within the brain, spinal cord, and peripheral nerves.

Studies at the University of Milan in Italy have shown that one of melatonin's primary functions, in conjunction with GABA (gabaamino-butyric-acid), is to inhibit the neuronal firing rate in the cortex of the brain in order to synchronize activity within the neuroendocrine system. Excessive or uncontrolled brain cell activity can contribute to movement disorders as in Parkinson's Disease and cognitive disorders as in Alzheimer's Disease. It can also contribute to the time-dependent declines of normal aging, which leads to progressive deterioration, culminating in the death of the organism. Taking 3-6 mg. of melatonin at night on a daily basis helps to resynchronize the clock, which slows aging and helps to prevent some of the diseases of aging.