cytochrome-c-t and euscaphic-acid

A compound was isolated from Potentilla chinensis, and it was identified as tormentic acid (TA) based on its physicochemical properties and spectral data. The hepatoprotective effect of TA was evaluated using an acute liver failure model induced by lipopolysaccharide (LPS)/D-galactosamine (D-GalN). The results revealed that TA significantly prevented LPS/D-GalN-induced fulminant hepatic failure, as evidenced by the decrease in serum aminotransferase and total bilirubin activities and the attenuation of histopathological changes. TA alleviated the pro-inflammatory cytokines including TNF-α and NO/iNOS by inhibiting nuclear factor-κB (NF-κB) activity. Moreover, TA strongly inhibited lipid peroxidation, recruited the anti-oxidative defense system, and increased HO-1 activity. In addition, TA significantly attenuated increases in TUNEL-positive hepatocytes through decreasing the levels of cytochrome c, as well as caspases-3, 8 and 9, while augmenting the expression of Bcl-2. In conclusion, TA protects hepatocytes against LPS/D-GalN-induced injury by blocking NF-κB signaling pathway for anti-inflammatory response and attenuating hepatocellular apoptosis. Consequently, TA is a potential agent for preventing acute liver injury and may be a major bioactive ingredient of Potentilla chinensis.

Topics: Animals; Anti-Inflammatory Agents; Caspases; Cytochromes c; Cytokines; Galactosamine; Heme Oxygenase-1; Lipid Peroxidation; Lipopolysaccharides; Liver; Liver Failure, Acute; Male; Membrane Proteins; Mice; Mice, Inbred C57BL; Nitric Oxide Synthase Type II; Phytotherapy; Potentilla; Protective Agents; Proto-Oncogene Proteins c-bcl-2; Transcription Factor RelA; Triterpenes

Chronic myeloid leukemia (CML) is a potentially fatal stem-cell cancer. P-glycoprotein (P-gp/ABCB1) activity has been described as a relevant factor in the chemotherapeutic failure and correlated to a poor prognosis in these malignancies. In the present study, we investigated the mechanism of the antineoplastic activity of 3β-acetyl tormentic acid (3ATA), a triterpene isolated from C. lyratiloba, on Lucena-1, an MDR leukemia cell line, that overexpressed P-gp/ABCB1. Results showing that this triterpene induced DNA-fragmentation, activation of caspase-3 and cytochrome c release indicated that its activity is mediated by the activation of the intrinsic pathway of apoptosis. Interestingly, this triterpene did not interfere with P-gp/ABCB1 expression or activity, indicating that induction of death is not mediated by any effect on this protein. Moreover, the results show that none of the others triterpenes from C. lyratiloba were able to modulate the activity of P-gp/ABCB1. Together these results suggest 3ATA and the other triterpenes as a promising material for the development of anti-neoplastic drugs for leukemia and other tumors independent of P-gp/ABCB1 activity or expression.

Topics: Antineoplastic Agents, Phytogenic; Apoptosis; ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily B, Member 1; Caspase 3; Cecropia Plant; Cytochromes c; Dose-Response Relationship, Drug; Drug Resistance, Neoplasm; Enzyme Activation; Humans; K562 Cells; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Time Factors; Triterpenes