Comparative Study between Damiana and Thyme on Nervous System Impairment during Aging

Abstract: : As we age, the brain begins to loose function and memory also concentration can be affected by age. Food has the ability to change the production or release of neurotransmitters, the chemical messengers that carry information from one nerve cell to another, by altering the chemical composition in the brain. The brain generates more free radicals per gram of tissue than any other organ, so brain cells need extra antioxidant protection. This study was aimed to examine the effect of damiana and thyme leaves powders and water extracts on brain oxidative status in aged rats and measure serum levels of neurotransmitters in order to compare between these plants and find out the best source and the most effective way to maintain or improve nervous system functions during aging. A total of 42 Sprague-Dawley aged male rats weighing 370 to 385 g were divided into 7 groups, each group contained 6 rats. The first group fed on basal diet and considered as a control group. The other 6 groups of rats were studied according to the following scheme for 30 days: (1) aged rats fed on basal diet and administered 2 mg aldomet (methyldopa, ), which is an effective antihypertensive drug but with adverse effect on nervous system and adrenergic receptors, Gr.(2) aged rats fed on basal diet + aldomet + 2 mg damiana water extract, Gr(3) aged rats fed on basal diet + aldomet + 2 mg thyme water extract, Gr(4) aged rats fed on basal diet + aldomet + 5% damiana powder, Gr(5) aged rats fed on basal diet + aldomet + 5% thyme powder and Gr(6) aged rats fed on basal diet + aldomet + 2.5% damiana powder + 2.5% thyme powder. Blood samples were taken from each rat. Antioxidant enzymes SOD, GSH and GPx activities were assayed in blood and MDA and neurotransmitters levels in serum were also measured. At the end of the experiment, antioxidant enzymes and malondialdehyde levels were measured in brains which also histopathologically examined. It could be found that thyme water extract achieved the highest increase in antioxidant enzymes SOD, GSH and GPx in aged rats brains. Thyme leaves water extract and powder caused the highest reduction in MDA in rats brains. The highest increase in antioxidant enzymes in serum of aged rats was achieved by using thyme water extract and reached about 66.73%, 62.69% and 25.17% for SOD, GSH and GPx activities, respectively, followed by thyme leaves powder. The highest reduction in serum MDA level was 17.32% by using thyme leaves water extract. Administration of aldomet to aged rats caused a significant increase in serum neurotransmitters: dopamine, serotonin, noradrenaline and adrenaline compared with control aged rats. Studied materials caused significant increase in serum neurotransmitters levels compared with control aged rats, while caused significant decrease compared with control rats administered with aldomet which had a favorable effect on nervous system functions during aging. The most abundant phenolic compounds found in thyme leaves were catechein, pyrogallol, caffeic acid and catechol. Chlorogenic acid and chrisin were not detected in damiana leaves. From chemical, biological and histopathological examination of the studied materials, It could be concluded that thyme leaves were more effective than damiana leaves in achieving the desired results and water extracts were better than powders when administered to aged rats to improve nervous system functions during aging.
Publication year 2012
Pages 50-61
Organization Name
serial title N Y Sci J
ISSN 1554-0200
Author(s) from ARC
Publication Type Journal
↑