Neurobiology of Fatigue and its Botanical Treatment

Abstract

Chronic fatigue is a multifaceted illness and is considered to be the seventh most common symptom in primary healthcare. Biology of fatigue is one of the least understood conditions in the medical science. Fatigue is most often chronic and at times severe in intensity. Chronic fatigue, either by itself or associated with other diseases, reduces quality of life and negatively affects personal, occupational and social activities. Chronic fatigue often occurs in aging and in various neurological, psychiatric, and systemic diseases including in aging, Parkinson's disease, multiple sclerosis, ALS, cancer, depression, and HIV infection. There is no safe and proven modern drug for fatigue. The kani, a high altitude living tribe in southern India traditionally use seeds of Trichopus zeylanicus (TZ) to enhance energy and to combat fatigue. The effectiveness of TZ whole plant powder on fatigue in normal, aged, animal model of aging and Parkinson's disease fatigue animal model was investigated. TZ (250 and 500 mg/kg) treated young Sprague-Dawley rats resisted fatigue at a significant level (p < 0.005) compared to controls by extended swim time in forced swim test. Oral TZ (500 mg/kg) treatment for two weeks significantly increased the mobility time in the aged mutant (p < 0.05) and normal mice (p < 0.01) and significantly increased swim time in the forced swim test in the aged normal mice (p < 0.05). Amphetamine-mimetic activity in TZ was excluded by suitable studies. Further studies showed that TZ contains NADH, polyphenols and sulfhydryl compounds, which have the ability to scavenge reactive oxygen species suggesting that the antioxidant activity may be an important mechanism of action of TZ to combat fatigue. TZ also possess significant and DNA protecting properties. Thus, TZ has potential to be developed as a safe and effective anti-fatigue drug.