Antidepressant effects of the water extract from Taraxacum officinale leaves and roots in mice

Context: The leaves and roots of the Taraxacum officinale F. (Asteraceae) is widely used as traditional medicinal herb in Eastern Asian countries.

Objective: In the present study, the antidepressant-like effects of the water extract of T. officinale (WETO) leaves and roots were investigated in mice using forced swimming test (FST), tail suspension test (TST) and open field test (OFT).

Materials and methods: Effects of acute (1-day) and chronic treatments (14-days) with WETO (50, 100 and 200?mg/kg) on the behavioral changes in FST, TST and OFT, and the serum corticotrophin releasing factor (CRF), adrenocorticotropic hormone (ACTH) and corticosterone concentration were assessed in mice.

Results: Chronic treatment (14-days) with WETO at the doses of 50, 100 and 200?mg/kg significantly decreased the immobility time in both FST (92.6, 85.1 and 77.4?s) and TST (84.8, 72.1 and 56.9?s). Acute treatment (1-day) with WETO at a dose of 200?mg/kg also markedly decreased the immobility time in both FST (81.7?s) and TST (73.2?s). However, all treatments did not affect the locomotor activity in the OFT. Moreover, FST induced a significant increase in serum CRF (5.8?ng/ml), ACTH (104.7?pg/ml) and corticosterone levels (37.3?ng/ml). Chronic treatment (14-days) with WETO decreased the serum CRF (200?mg/kg: 3.9?ng/ml) and corticosterone (50?mg/kg: 29.9?ng/ml; 100?mg/kg: 22.5?ng/ml; 200?mg/kg: 19.8?ng/ml) levels.

Discussion and conclusion: These results clearly demonstrated the antidepressant effects of WETO in animal models of behavioral despair and suggested the mechanism involved in the neuroendocrine system.