LACK OF FOLIC ACID LINKED TO PARKINSON'S DISEASE
Folic acid deficiency could increase the brain's susceptibility to Parkinson's disease, according to scientists at the National Institute on Aging. The findings, published in the January issue of the Journal of Neurochemistry, says mice that were fed folate, and then given MPTP which causes Parkinson-like symptoms, developed only mild symptoms of the disease. The scientists found that mice with low amounts of dietary folic acid had elevated levels of homocysteine in the blood and brain. The researchers suspect that increased levels of homocysteine in the brain caused damage to the DNA of nerve cells in the substantia nigra, an important brain structure that produces dopamine. Loss of dopamine causes the nerve cells to dysfunction, leaving patients unable to direct or control their movement in a normal manner. In mice fed adequate amounts of folate, dopamine-producing nerve cells were able to repair damaged DNA and counteract the adverse effects of homocysteine. However, similar nerve cells in folate-deficient mice could not repair the extensive DNA damage. "This is the first direct evidence that folic acid may have a key role in protecting adult nerve cells against age-related disease," says Mark Mattson, Ph.D.
REDUCING STOMACH ACID INCREASES GASTRITIS
When it comes to cooling the burning pain of gastritis or an inflamed stomach lining, reducing the amount of acid in the stomach may seem like a good idea. But two studies with laboratory mice, conducted by Howard Hughes Medical Institute scientists at the University of Michigan Medical School, indicate it could be exactly the wrong thing. The scientists found that antibiotics were the best way to kill the bacteria that cause gastritis and eliminate stomach inflammation in their experimental mice. Mice treated with prescription drugs called proton pump inhibitors or PPIs, which block acid production, acquired more bacteria and developed more inflammatory changes in their stomach linings than untreated mice. "These animal studies indicate that it is the inflammatory response -- triggering the overproduction of hydrochloric acid -- which is the stomach's primary response to bacterial colonization," says Juanita L. Merchant, M.D. "Inflammation of the stomach lining coincides with production of peptides called cytokines, which stimulate production of a hormone called gastrin." Gastrin triggers parietal cells in the stomach lining to produce more hydrochloric acid, which kills off most invading microbes. "If you inhibit gastric acid production, you interfere with the stomach's natural defense mechanism," says Merchant.
WOMEN WAIT TO BUILD HIERARCHIES
A study in the January edition of the Personality and Social Psychology Bulletin may show that men and women both form dominance hierarchies but act differently when first entering a new group. The study, conducted at Northeastern University and the University of Zurich in Switzerland, is the first to examine women's patterns in dominance structures, according to Marianne Schmid Mast. Her study shows that women build hierarchies among themselves naturally, but they determine their structure differently from men. In a social setting or a large meeting, women begin relationships in a more impartial manner, waiting to form hierarchies long after their male counterparts, who tend to enter a room and dominate others. However, women gather their power slowly and carefully and form alliances just as hierarchical and powerful as men do. "Women may feel more comfortable to form hierarchies after getting to know the people in any new group," says Mast. "When running a business, a newly-hired female executive may feel the need to interact with her group before assigning work, while many men would immediately take charge and would delegate from the get-go."
DREAMS MAY PROVIDE CLUE TO DEPRESSION
Research being conducted at Rush-Presbyterian-St. Luke's Medical Center in Chicago has provided doctors here with a glimpse into how the dreams of those who are depressed from a recent divorce may contribute to overcoming depression. This may provide clues why some people seem to recover from depression while others do not. Rosalind Cartwright, Ph.D., and colleagues designed a study to test the hypothesis that if people depressed after a marital break up will emotionally adjust more rapidly if they are able to construct and recall well-developed, emotionally rich dreams. "The preliminary data suggest that emotional problem solving takes place during dreaming," Cartwright says. Preliminary data reveals that when dreams of the ex-spouse are seen in a casual or distant manner, the recently separated or divorced person will begin to recover and cope with the life change. Those who are not coping well with a recent marital separation have sparse dreams, and if the ex-partner appears at all in the dreams, they are seen in a negative role, often as weak, rejecting or punishing. "We find that when feelings in the dreams that are reported just before the morning wake up time are negative, the person is likely to have a continuing depressive mood," Cartwright says.
(EDITOR: For more information, about PARKINSON'S, call 301 496-1752; about GASTRITIS, call 734 615-6912; about HIERARCHIES, call 617 373-5739; about DREAMS, call 312 942-3686.)
