Synthesis of Quercetin-Acid Esters and Its Reduction of H2 O2 -Triggered PC12 Cells Damage by Down-Regulating ROS.

Quercetin is a kind of polyphenolic flavonoid compounds which has perfect antioxidant properties. However, quercetin is not available in many situations due to its poor bioavailability. In this work, the QAEs with better solubility and even stronger antioxidant properties were synthesized, through the esterification between quercetin and the chlorinated cinnamic acid or its derivatives, whose chlorination were achieved by using SOCl2 . The protective effects of the QAEs were evaluated by the H2 O2 -induced apoptosis experiment in rat adrenal pheochromocytoma cells (PC12 cells) and its ability to remove ROS generated by oxidative stress. Compared with the original quercetin group, the QAEs groups showed much improved cell viability and capability of removing ROS, which means their higher bioavailability than the parent.

Two macamide extracts relieve physical fatigue by attenuating muscle damage in mice.

BACKGROUND: Macamides, the main active components contained in maca, have attracted increasing attention due to their various bioactivities. In this study, crude macamide extract (CME) and purified macamide extract (PME) were prepared by enzyme-assisted extraction and macroporous resin separation, and the anti-fatigue effects of CME and PME were evaluated in a forced swimming model. RESULTS: The composition analysis results revealed that both CME and PME mainly contain eight kinds of macamide. Based on the results of a weight-loaded forced swimming test, compared with a control group, CME and and PME groups could prolong exhaustive swimming time, increase levels of liver glycogen (LG) and muscle glycogen (MG), accelerate fatty acid oxidation in serum to provide energy, eliminate the accumulation of blood lactic acid (BLA) and blood urea nitrogen (BUN), and decrease the serum biomarkers for muscle damage, such as lactate dehydrogenase (LDH) and creatine kinase (CK). Histological analysis also indicated that CME and PME attenuated damage to skeletal muscle and the myocardium in mice during exercise. CONCLUSION: Two macamide extracts have a beneficial effect on relieving physical fatigue by attenuating the damage of skeletal muscle and myocardium during exercise, and a better effect was observed in the PME group. © 2018 Society of Chemical Industry.

Synthesis, in silico and in vivo blood brain barrier permeability of ginkgolide B cinnamate.

Ginkgolide B, one of the important components of Ginkgo biloba extracts, has been revealed to exhibit great potential in therapy of cerebrovascular diseases. However the lack of permeability greatly limited it from further clinical application. Based on the prediction model for blood brain barrier (BBB) permeation, herein a potential brain-targeting analog ginkgolide B cinnamate (GBC) was successfully synthesized and characterized. After intravenous administration of GBC or GB, liquid chromatography tandem mass spectrometry (LC-MS/MS) was conducted to determine the analog in rat plasma and brain. The results showed that GBC had a significant increase in BBB permeability. A significant 1.61-times increase in half-life was observed for GBC and the drug targeting index (DTI) value was calculated to be 9.91. The experiment results matched well with the predicted one, which revealed that BBB permeability prediction model combined with in vivo study could be used as a quick, feasible and efficient tool for brain-targeting drug design.

Comparison of prediction models for blood brain barrier permeability and analysis of the molecular descriptors.

To develop an in silico model for predicting blood brain barrier (BBB) permeability, and evaluate whether incorporation of two new biological descriptors, high affinity P-glycoprotein substrate probability (HAPSP) and plasma protein binding ratio (PPBR), could result in a better model, four different multiple linear regression (MLR) models have been constructed and compared with each other. The optimized model demonstrated predictive ability and simplicity, not only suitable for passive but also for active transport. Moreover, the molecular descriptors used here are discussed.