Research - Dandelion / Taraxacum officinale
Antidepressant effects of the water extract from Taraxacum officinale leaves and roots in mice
.Li YC1, Shen JD, Li YY, Huang Q.
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.
Source : Pharm Biol.
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Anti-Inflammatory Effect of Taraxacum officinale Leaves on Lipopolysaccharide-Induced Inflammatory Responses in RAW 264.7 Cells
To investigate the efficacy and the mechanism of the anti-inflammatory effect of Taraxacum officinale leaves (TOLs), the effect of a methanol extract and its fractions recovered from TOLs on lipopolysaccharide (LPS)-induced responses was studied in the mouse macrophage cell line, RAW 264.7. Cells were pretreated with various concentrations of the methanol extract and its fractions and subsequently incubated with LPS (1 μg/mL). The levels of nitric oxide (NO), prostaglandin (PG) E2, and pro-inflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 were determined using enzyme-linked immunosorbent assays. Expressions of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 and activation of mitogen-activated protein (MAP) kinases were analyzed using western blotting. The methanol extract and its fractions inhibited LPS-induced production of NO, pro-inflammatory cytokines, and PGE2 in a dose-dependent manner. The chloroform fraction significantly suppressed production of NO, PGE2, and two pro-inflammatory cytokines (TNF-α and IL-1β) in a dose-dependent manner with 50% inhibitory concentration values of 66.51, 90.96, 114.76, and 171.06 μg/mL, respectively. The ethyl acetate fraction also inhibited production of the inflammatory molecules. The chloroform and ethyl acetate fractions reduced LPS-induced expressions of iNOS and COX-2 and activation of MAP kinases in a dose-dependent manner. Among the fractions of the methanol extract, the chloroform and ethyl acetate fractions exhibited the most effective anti-inflammatory activities. These results show that the anti-inflammatory effects of TOLs are probably due to down-regulation of NO, PGE2, and pro-inflammatory cytokines and reduced expressions of iNOS and COX-2 via inactivation of the MAP kinase signal pathway.
Source : Journal of Medicinal Food
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Antioxidant Properties of Taraxacum officinale Leaf Extract Are Involved in the Protective Effect Against Hepatoxicity Induced by Acetaminophen in Mice
Dirleise Colle,1Leticia Priscilla Arantes,1Priscila Gubert,1Sonia Cristina Almeida da Luz,2 Margareth Linde Athayde ,3Joa ̃o Batista Teixeira Rocha,1and Felix Alexandre Antunes Soares1
1Department of Chemistry, Natural and Exact Sciences Center; Departments of 2Pathology and 3Industrial Pharmacy ,Health Sciences Center; Federal University of Santa Maria, Santa Maria, Rio Grande do Sul, Brazil
Acetaminophen (APAP) hepatotoxicity has been related to several cases of hepatitis, cirrhosis, and hepatic transplant. As APAP hepatotoxicity is related to reactive oxygen species (ROS) formation and excessive oxidative stress, natural antioxidant compounds have been tested as an alternative therapy to diminish the hepatic dysfunction induced by APAP. Taraxacum officinale Weber (Family Asteraceae), commonly known as dandelion, is used for medicinal purposes because of its choleretic, diuretic, antioxidant, anti-inflammatory, and hepatoprotective properties. This study evaluated the hepatoprotective activity of T. officinale leaf extract against APAP-induced hepatotoxicity.T. officinale was able to decrease thiobarbituric acid–reactive substance levels induced by 200 mg/kg APAP (p.o.), as well as prevent the decrease in sulfhydryl levels caused by APAP treatment. Furthermore, histopathological alterations, as well as the increased levels of serum aspartate and alanine aminotransferases caused by APAP, were prevented by T. officinale(0.1 and 0.5 mg/mL). In addition, T. officinale extract also demonstrated antioxidant activity in vitro, as well as scavenger activity against 2,2-diphenyl-1-picrylhydrazyl and nitric oxide radicals. Our results clearly demonstrate the hepatoprotective effect of T. officinale against the toxicity induced by APAP. The possible mechanisms involved include its scavenger activities against ROS and reactive nitrogen species, which are attributed to the content of phenolic compounds in the extract.
Source : Journal of Medicinal Food
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