Oh, That Jet Lag!

Sara G. Miller, a staff writer for Live Science, composed an article giving us a heads up on recovering from jet lag.

Deep inside our brains is our biological clock.  It may be possible to reset it by targeting certain cells in our eyes, according to a new study.  This may lead to the development of eye drops that could be used to help people adjust to jet lag someday, as the researchers wrote in a study published in The Journal of Physiology.

Because the study was done in lab rats, there is much more research needed to confirm that the findings will also apply to humans.  There is an area of the brain that the scientists know about that is called the suprachiasmatic nucleus (SCN) that controls a person’s biological clock.  It releases signaling molecules that travel throughout the body.  One is called vasopressin, but the SCN doesn’t simply “know” what biological time it is. It gets information from the cells in the eyes that respond differently to light of different intensities.  For example, the bright light in the morning helps to synchronize a person’s biological clock while bright light at night can throw the clock out of whack.  Traveling across time zones exposes us to bright light at different times of day which the body doesn’t expect, and then results in jet lag.

Relaying the info about light intensity is through the cells in the eyes that are called retinal ganglion cells.  These are different from other cells in the eyes, such as the rods and cones that are responsible for telling the brain what a person actually is seeing.   It isn’t really understood how these cells communicate with the biological clock in the brain.  The researchers found in rats that the eyes’ retinal ganglion cells also produce the signaling molecule called vasopressin and this signaling molecule travels from the eyes to the brain to help regulate the biological clock.

The researchers showed in an experiment that a bright pulse of light excited the retinal ganglion cells in the eye of the rats, causing them to release vasopressin.  In another, they showed that after a pulse of light, the neurons in the brain’s suprachiasmatic nucleus were activated as well.  When a compound was injected to brain cells that blocked vasopressin, the brain cells responded less to the same pulse of light.  This suggests vasopressin from the cells in the eye does play a role in regulating the biological clock and could lead to the development of drugs that could also adjust the biological clock, according to senior study author Mike Ludwig, a professor of neurophysiology at the University of Edinburgh in Scotland.

If they can come up with a way to alter the levels of vasopressin that comes from the eye, they might potentially be able to develop an eye drop that could help us to recover from jet lag when traveling.

Till then, drink lots of fluids (not alcohol), take naps, light exercise, and eat properly. Enjoy your trips.

Fredda Branyon