Screening Multidrug Resistance Reversal Agents in Traditional Chinese Medicines by Efflux Kinetics of D-Luciferin in MCF-7/DOXFluc Cells.

In this study, we established a simple and rapid in vitro method for screening multidrug resistance (MDR) reversal agents in traditional Chinese medicines (TCMs), which could better correspond to the MDR reversing effect in vivo. Here, D-luciferin, a substrate for the enzyme firefly luciferase and also a substrate for ATP-binding cassette transporters (ABC transporters), was used as the probe to detect its efflux kinetics caused by ABC transporters. First, we established a stable doxorubicin (DOX)-resistant cell line (MCF-7/DOXFluc) that overexpressed luciferase. Then, some kinds of TCMs were chosen for the MDR reversal agents to measure its effect on inhibiting the D-luciferin outflow from MCF-7/DOXFluc, and the ideal reversal agent with the least D-luciferin efflux from MCF-7/DOXFluc was selected to further investigate its effect combined with DOX on MCF-7/DOXFluc tumor-bearing mice. The results indicated that quercetin (Qu) could remarkably increase the retention of D-luciferin in MCF-7/DOXFluc in vitro and in vivo. Also, the combination of Qu and DOX could exceedingly inhibit the tumor growth, which proved the feasibility of this in vitro screening method. The study proposed a feasible method for mass screening of MDR agents from TCMs in vitro.

Degradation of rhodamine B by persulfate activated with green tea iron nanoparticles.

Green iron tea nanoparticles (GT-Fe NPs) were used as persulfate(PS) activators to oxidize rhodamine B (RhB) in this study. Optimized oxidative degradation condition was 0.033 mM Fe, 5 mM PS at pH 3.0 and 298 K with an initial RhB content of 50 mg/L. After 120 min of RhB degradation utilizing GT-Fe NPs activated PS, 99% of RhB reduction was achieved, while 98% RhB reduction with PS activated by citric acid-Fe2+(CA-Fe) with the same amount of Fe2+. This RhB reduction was due to the delayed release of Fe(II) in the GT-Fe NPs. The addition of GT-Fe NPs enhanced the synthesis of OH· and SO4-· while inhibiting the formation of O2-·. A possible RhB degradation pathway was the chromophore destruction and ring-opening processes using GT-Fe NPs/PS, which produced a range of low molecular weight carboxylic acids (oxalic acid, lactic acid, acetic acid, and formic acid). GT-Fe NPs seem to be a promising persulfate activator in comparison to common activators such as CA-Fe.

3ß-Angeloyloxy-8ß,10ß-dihydroxyeremophila-7(11)-en-12,8α-lactone Inhibits Lipopolysaccharide-Induced Nitric Oxide Production in RAW264.7 Cells.

Farfugium japonicum (L.) KITAM, named "Lian-Peng-Cao" in China, has been traditionally used in Chinese folk medicine to treat sore throat, cold and cough due to its anti-inflammatory properties. In this study, the anti-inflammatory action of 3ß-angeloyloxy-8ß,10ß-dihydroxyeremophila-7(11)-en-12,8α-lactone (FJ1) isolated from Farfugium japonicum and its molecular mechanism in RAW264.7 cells were investigated. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that FJ1 with or without 3 µg/mL lipopolysaccharide (LPS) had no significant cytotoxicity in RAW264.7 cells. The production of nitric oxide (NO) was identified with a Griess reagent kit. The mRNA expression of inducible nitric oxide synthase (iNOS) and cytokines, including tumor necrosis factor α (TNF-α) and cyclooxygenase-2 (COX-2), was measured by real-time polymerase chain reaction (PCR). Reactive oxygen species (ROS) production was detected by flow cytometry analysis. Western blot was used to examine the protein expression of nuclear factor-kappa B (NF-κB)/p65, inhibitor of kappa B (IκB)-α, phosphorylated IκB-α (p-IκB-α), mitogen-activated protein kinase (MAPK) molecules, iNOS, and TNF-α. We discovered that FJ1 possesses anti-inflammatory effects that inhibit the release of LPS-stimulated pro-inflammatory cytokines, including NO and ROS. The molecular mechanism of FJ1-mediated anti-inflammation is associated with decreasing phosphorylation of MAPK molecules, including extracellular signal-related kinase 1/2 (ERK1/2), p38 MAPK, and c-Jun NH2-terminal kinase (JNK), FJ1 also reverses IκB degradation and attenuates the mRNA and protein expression of NF-κB-related downstream inducible enzymes and cytokines, such as iNOS, TNF-α in RAW264.7 cells. The results suggest that FJ1 has anti-inflammatory properties, which indicates that F. japonicum can be utilized to treat inflammatory diseases. The potential mechanism is associated with the NF-κB and MAPK activation pathways in LPS-stimulated macrophages.

Telekin induces apoptosis associated with the mitochondria-mediated pathway in human hepatocellular carcinoma cells.

Telekin, a eudesmane-type sesquiterpene lactone compound isolated from Chinese folk medicine Carpesium divaricatum, has been reported to strongly inhibit the proliferation of cancer cells. In this study, the involvement of a mitochondria-mediated pathway in the pro-apoptotic action of telekin was investigated in human hepatocellular carcinoma cells. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays showed that telekin exhibited excellent anti-proliferation activity in hepatocellular carcinoma cells and low cytotoxicity to normal hepatocyte cells. Telekin-induced apoptosis was characterized by chromatin condensation, formation of apoptotic bodies, and exposure of phosphatidylserine on the extracellular surface, as revealed by 4,6-diamidino-2-phenylindole (DAPI) nuclear staining and flow cytometry. Flow cytometry analysis showed that telekin induced the loss of mitochondrial membrane potential (MMP), as well as increased the levels of intracellular free calcium and reactive oxygen species (ROS). Additionally, Western blot results demonstrated that telekin induced the decrease in Apaf-1 and Bcl-2 expression, increase in Bax expression, release of cytochrome C, and activation of caspase-9 and caspase-3 in HepG-2 cells. These findings indicate that telekin activates the mitochondria-mediated apoptotic pathway in hepatocellular carcinoma cells and may merit further investigation as a potential therapeutic agent for the treatment of hepatocellular carcinoma.

Sesquiterpenoids from Carpesium divaricatum and their cytotoxic activity.

In the course of searching for cytotoxic terpenoids from medicinal plants in China, two new eudesmane sesquiterpenoids, 5α-hydroxy-13-methoxy-7αH,11αH-eudesm-4(15)-en-12,8ß-lactone (1) and 1ß-hydroxy-7αH,11αH-eudesm-4(15)-en-12,8ß-lactone (2), along with fourteen known sesquiterpenoids were isolated from the whole plant of Carpesium divaricatum. The structures of new compounds were determined using spectroscopic methods, including IR, HRESIMS, and 1D and 2D NMR spectroscopy. The cytotoxicity of selected sesquiterpene lactones against human oral epidermoid carcinoma (KB), human breast cancer (MCF-7) and human hepatoma (HepG-2) cells was also evaluated by MTT method.