Wednesday, October 01, 2008 Literatus: Out of the blue By Zosimo T. Literatus, R.M.T. Breakthroughs
British poet John Keats graphically described his depression in a letter to Benjamin Bailey: “I am in that temper that if I were underwater I would scarcely kick to come to the top.” Things look heavier than they are; the world appears darker than it can be. It is a deep, unshakable sadness that diminishes interest in all activities.
Depression is one of the most common mental illnesses around the world, and seemingly more prevalent among women than among men, based on studies after studies.
Most psychologists believe depression results from an interaction between stressful life events and a person’s biological and psychological vulnerabilities.
All of which, however, are biochemical in nature, and can be altered so by drugs and herbal preparations.
Two popular herbs used against depression are the leaves of Perilla (Perilla frutescens) and sage (Salvania officinalis).
Perilla and sage contain an active ingredient known as rosmarinic acid, an antidepressant proven in clinical trials using animals.
Studies, however, indicated it is the rosmarinic metabolite (caffeic acid) that directly caused its antidepressant effect.
How it works? That remains unknown; scientists believe though that it has something to do with its action on the hippocampus — the memory and learning region of the brain — particularly the dentate gyrus, a tooth-like structure in the hippocampus.
Seven researchers from various research centers of the Kitasato University (Tokyo, Japan) ventured to check if that was so. Their study on mice got published this year at the Biological Pharmacy Bulletin by the Pharmaceutical Society of Japan.
The team injected the three groups of mice with three doses of rosmarinic acid: 1.0, 2.0 and 4.0 mg/kg body weight from seven to 14 days and tested them using forced swimming, open field and immunochemical analysis.
Mice treated with 2.0 mg/kg dose for seven days swam longer by 36 percent compared to those receiving no rosmarinic acid. The 4.0-dose group lasted 38 percent more. The 14-day treatment showed better results. A dose of 1.0 mg/kg lasted 37 percent more, 2.0 by 40.5, and 4.0 by 48.5. This result, lead research Naoki Ito wrote, is “dose- and time-dependent.”
Movement duration and distance in open space showed no difference in all doses and treatment periods, an indicator of its more pronounced impact under stressful situations.
Cells in the dentate gyrus multiplied at a rate of 30.8 percent more in the 2.0 mg/kg dose, and 44.7 in the 4.0 dose for the seven-day treatment period. In the 14-day period, the cells increased 42.8 percent in 1.0 mg/kg, 48.9 in 2.0, and 79.9 in 4.0.
So perhaps the next time around, chewing green leaves of Perilla and sage will do to get out to the blue.
