Travel can be a joy, except for that first day or so when jet lag sets in. While not a serious condition, jet lag can nonetheless disturb digestion, alter your mood and disrupt your ability to concentrate. While supplements including melatonin as well as light therapy have been shown to help the symptoms of jet lag, there is no real cure except time. New research out of the Physiological Society in the UK however, might one day make getting over your disrupted body clock as simple as taking a few eye drops.
The researchers, led by Mike Ludwig, Professor of Neurophysiology at The University of Edinburgh, say that for the first time ever, it's been discovered that our retinas have cells in them that create a hormone known as vasopressin.
While vasopressin's primary role is maintaining the balance of particles in the fluid surrounding our cells, it's been known that hormone, along with other chemicals, are used by the region of our brain known as the suprachiasmatic nucleus (SCN) in our hypothalamus to regulate our circadian rhythms. "Circadian rhythms are physical, mental and behavioral changes that follow a roughly 24-hour cycle, responding primarily to light and darkness in an organism's environment," says the US National Institute of General Medical Sciences. It is the disruption to those rhythms that causes jet lag.
Finding that not only do our eyes themselves also make vasopressin, but that those cells also communicate directly with the SCN, provided the researchers with a path of inquiry: They inhibited the retinal vasopressin-producing cells in rats and discovered that the creatures did not suffer the symptoms of jet lag.
The discovery makes the researchers hopeful that developing simple methods to suppress vasopressin in the retina could keep jet lag – and its symptoms – at bay, although they are cautious to point out that much more research will be needed.
"Our exciting results show a potentially new pharmacological route to manipulate our internal biological clocks," says Ludwig. "Studies in the future which alter vasopressin signaling through the eye could lead to developing eye drops to get rid of jet lag, but we are still a long way off from this."
The study has been published in the Journal of Physiology.
Source: The Physiological Society