inducing resuscitation with herbal aromatics is important to modulate the brain intake of drugs in traditional Chinese medicine,but limited information has been available on the mechanism of action.The MDCK-MDRl monolayer is an excellent in vitro cell model to use as a tool to study blood brain barrier(BBB) screening.In this study,we established MDCK-MDR1 cell line by stable transfection and investigated the effects of several important herbal aromatics on BBB permeability.The characterization experiment demonstrated the MDCK-MDRl used in this study was valid.In a transport study,we found several herbal aromatics increased the permeability of fluorescein isothiocyanate-labeled dextran 4kDa(FD4) and inhibited efflux of Rhodaminel23(Rhol23).These results demonstrated that herbal aromatics enhanced the BBB permeation of drugs by both inhibition of P-gp and opening of the BBB tight junction,thus providing new insights for understanding the mechanisms of aromatic compounds' BBB permeability.
Abstract: Vanadium compounds are promising therapeutic agents for the treatment of diabetes and cancer. However, vanadium toxicity has been a great concern. Many works suggested that vanadium-induced oxidative stress is a major reason of vanadium toxicity. Quercetin and green tea polyphenols (GTP) are well-known antioxidants that play important roles in the prevention of many oxidative stress-related diseases. In this study, we investigated the protective effects of quercetin and GTP against damages caused by VO(acac)2 on isolated mitochondria and whole cells. The experimental results demonstrated that quercetin and GTP could significantly inhibit mitochondrial dysfimctions induced by VO(acac)2, such as mitochondrial swelling, depolarization of the inner mitochondrial membrane potential (△ψm), and increased release of reactive oxygen species (ROS). Moreover, they also reduce cytotoxicity in Hep G2 cells. These results indicated that use of natural antioxidants to control the metal toxicity of vanadium compounds may be a promising strategy for developing metal-based therapeutic agents.
Vanadium compounds show potential in diabetes and cancer treatment, although the toxicity remains a great concern. Previous studies have shown that vanadium-induced oxidative stress affecting mitochondrial function is intensively responsible for the toxicity. In this work, we investigated the effects of the vanadium compounds sodium metavanadate (NaVO3) and vanadyl acetylacetonate (VO(acac)2) on mitochondrial ROS generation and respiratory complex activities. The experimental results showed that vanadium compounds affected the ROS generation and complex activities in different patterns depending on the chemical species. NaVO3 inhibited mitochondrial complexes Ⅰ and Ⅱ activities and stimulated ROS generation at low concentration range; while VO(acac)2 promoted complex Ⅱ activity but resulted in electron leakage from the complex Ⅰ-involved pathway. The present results provide new evidence for understanding the toxicity of antidiabetic vanadium compounds.