Synergistic cytotoxicity of erianin, a bisbenzyl in the dietetic Chinese herb Dendrobium against breast cancer cells.

Erianin (ER), a dietary compound extracted from Dendrobium, a traditional Chinese medicinal edible herb, is well recognized for its potential anti-cancer activity. Nevertheless, its limitations, regarding its complex isolation procedure, low yield and low water solubility, limit large scale application. Combinatorial therapeutic regimen that combines several drugs to target different pathways in a characteristically synergistic manner at lower doses of drugs proved effective in several diseases treatment. Besides, new knowledge aimed at improving drug delivery into the intracellular environment is essential. In this study, ER was assessed for its cytotoxic effect in combination with doxorubicin hydrochloride (DOX·HCl) against breast cancer cells. Drug synergy was calculated by using combination index (CI) index and we discovered that they had positive effects. To ensure uniform delivery of both drugs to cells for a desired synergistic action, a dual drug loaded liposomes was developed using thin-film dispersion, and coated by a layer of folate-chitosan. Cytotoxicity and cell proliferation based assays revealed the increase of cell inhibition rate by more than 30% compared with free drugs. Fluorescence imaging revealed that liposomes can aid faster drugs accumulate in cancer cells. The study presented a novel strategy for the treatment of breast cancer.

Dihydro-stilbene gigantol relieves CCl4-induced hepatic oxidative stress and inflammation in mice via inhibiting C5b-9 formation in the liver.

In general, anti-inflammatory treatment is considered for multiple liver diseases despite the etiology. But current drugs for alleviating liver inflammation have defects, making it necessary to develop more potent and safer drugs for liver injury. In this study, we screened a series of (dihydro-)stilbene or (dihydro-)phenanthrene derivatives extracted from Pholidota chinensis for their potential biological activities. Among 31 compounds, the dihydro-stilbene gigantol exerted most potent protective effects on human hepatocytes against lithocholic acid toxicity, and exhibited solid antioxidative and anti-inflammatory effect in vitro. In mice with CCl4-induced acute liver injury, pre-administration of gigantol (10, 20, 40 mg· kg-1· d-1, po, for 7 days) dose-dependently decreased serum transaminase levels and improved pathological changes in liver tissues. The elevated lipid peroxidation and inflammatory responses in the livers were also significantly alleviated by gigantol. The pharmacokinetic studies showed that gigantol was highly concentrated in the mouse livers, which consisted with its efficacy in preventing liver injury. Using a label-free quantitative proteomic analysis we revealed that gigantol mainly regulated the immune system process in liver tissues of CCl4-treated mice, and the complement and coagulation cascades was the predominant pathway; gigantol markedly inhibited the expression of complement component C9, which was a key component for the formation of terminal complement complex (TCC) C5b-9. These results were validated by immunohistochemistry (IHC) or real time-PCR. Confocal microscopy analysis showed that gigantol significantly inhibited the vascular deposition of TCC in the liver. In conclusion, we demonstrate for the first time that oral administration of gigantol potently relieves liver oxidative stress and inflammation, possibly via a novel mechanism of inhibiting the C5b-9 formation in the liver.

Resveratrol, lunularin and dihydroresveratrol do not act as caloric restriction mimetics when administered intraperitoneally in mice.

Resveratrol as well as caloric restriction were shown to extend lifespan in some model organisms and may possibly delay onset of ageing-related diseases in humans. Yet, resveratrol supplementation does not always extend lifespan of animal models or improve health status of humans. Because of interindividual differences in human microbiota, resveratrol metabolite production in the gut differs. While some individuals produce lunularin and dihydroresveratrol in their gut, others produce dihydroresveratrol only. Therefore, we addressed the question whether these metabolites differ in their biological impact on ageing and intraperitoneally injected 13-month-old C57BL/6JRj mice on an ad-libitum (AL) HFD with resveratrol, dihydroresveratrol or lunularin (24 mg/kg bodyweight; 3 times/week). Compared to mice injected with vehicle (AL-control), resveratrol and dihydroresveratrol did not change bodyweight and had no impact on insulin or glucose levels while lunularin slightly reduced feed intake and bodyweight gain. CR-mice showed lowered cholesterol, insulin and leptin levels, elevated adiponectin and phosphorylated AMPK levels in liver as well as increased transcription of Pck1 and Pgc1α when compared to the AL-control. In contrast, injections with the test substances did not change these parameters. We therefore conclude that in our model, resveratrol, lunularin and dihydroresveratrol did not act as CR mimetics.

Combretastatins D-3 and D-4, new macrocyclic lactones from Getonia floribunda.

Chemical investigation of biologically active compounds of Getonia floribunda led to the isolation of two new macrocyclic lactones, combretastatins D-3 (1) and D-4 (2). The structures of these compounds were confirmed by spectroscopic analyses. Combretastatin D-3 (1) exhibited cytotoxicity towards the small-cell lung cancer cell line (NCI-H187, IC50=13.0 +/- 0.2 microg/mL) but was inactive against KB, BC-1, and Vero cell lines. Combretastatin D-3 (1) showed weak antitubercular activity with a minimum inhibitory concentration (MIC) of 100.0 microg/mL, and was inactive towards the malarial parasite. Combretastatin D-4 (2) was inactive in all antitubercular, antiplasmodial, and cytotoxic assays.