Anti-Inflammatory Effect ofTaraxacum officinaleLeaves on Lipopolysaccharide-Induced Inflammatory Responses in RAW 264.7 Cells

Abstract

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 microg/mL). The levels of nitric oxide (NO), prostaglandin (PG) E(2), and pro-inflammatory cytokines including tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, 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 PGE(2) in a dose-dependent manner. The chloroform fraction significantly suppressed production of NO, PGE(2), and two pro-inflammatory cytokines (TNF-alpha and IL-1beta) in a dose-dependent manner with 50% inhibitory concentration values of 66.51, 90.96, 114.76, and 171.06 microg/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, PGE(2), and pro-inflammatory cytokines and reduced expressions of iNOS and COX-2 via inactivation of the MAP kinase signal pathway.

Antioxidant properties ofTaraxacum officinalefruit extract are involved in the protective effect against cellular death induced by sodium nitroprusside in brain of rats

“…Flavonoids and phenolic compounds, such as luteolin, caffeic acid, and cholorgenic acid, are found in extracts of T. officinale (Hu & Kitts, 2003;Domitrovic et al, 2010;Koh et al, 2010). These compounds, which are generally found in plants, protect cells from oxidative stress by preventing the formation of free radicals or by detoxifying free radicals, resulting in the prevention of a variety of pathophysiological processes (Mates & Sanchez-Jimenez, 2000).…”

Chinese herbal Jin-Ying-Tang attenuates the inflammatory response by inhibiting the activation of TLR4/MyD88/TRAF-6/NIK pathway at the mRNA level in LPS-stimulated mouse mammary epithelial cells

“…Taraxacum mongolicum Hand.-Mazz. shows anti-inflammatory activity through the inhibition of TNF-α and IL-1 production, and COX-2 expression (15). Lonicerae macranthoides Hand.-Mazz.…”

Solubility and solubilizing capabilities of aqueous solutions of Extractum Taraxaci e radix cum herba aqu. siccum in light of selected values of general Hildebrand-Scatchard-Fedors theory of solubility

“…Comprehensive studies on T. officinale extraction product, methanol, chloroform and ethyl acetate [3] confirmed their high anti-inflammatory activity, whereas sterile lyophilized "decoctum" from Taraxaci effectively affected the progression of immune parameters in mice [4].…”

“…The process of micellar solubilization was performed in a container of V=100 cm 3 into which there were weighed not less than 0.350 g of homogeneous cholesterol granules of φ=1.00 mm, in the case of ketoprofen the weighed quantity did not exceed 0.3530 g. Then, 25.0 cm 3 of the aqueous solution of the extract was pipetted into 0.1 mol HCl and phosphate buffer of pH=6.88. The containers were fixed in EIPIN+375 water bath shaker at bath temp.…”