Content Determination of Chlorogenic Acid and Luteoloside in Flos Lonicerae

The contents of chlorogenic acid and luteoloside in Flos Lonicerae from Binhai New Area and Jinnan District of Tianjin were determined to provide basis for the quality identification of this medicinal material. The content of chlorogenic acid was determined by HPLC. In Flos Lonicerae from Binhai New Area and in Flos Lonicerae harvested at different stages from Jinnan District,the contents of chlorogenic acid were 3. 804%,5. 507%( three green stage),4. 855%( silver flower stage) and 4. 220%( golden flower stage),respectively,and the contents of luteoloside were 5. 53%,12. 405%( three green stage),14. 370%( silver flower stage) and 0. 917%( golden flower stage),respectively. The contents of chlorogenic acid in Flos Lonicerae from Jinnan District were higher than that from Binhai New Area. Among different stages,the content of chlorogenic acid was highest in three green stage,followed by that in silver flower stage. As the flowers bloomed,the content of chlorogenic acid in the medicinal material showed a significant downward trend. In Flos Lonicerae from Jinnan District,the content of luteoloside was highest in silver flower stage and lowest in golden flower stage.

Luteoloside protects the vascular endothelium against iron overload injury via the ROS/ADMA/DDAHⅡ/eNOS/NO pathway

Iron overload injury is considered to be a part of blood stasis syndrome of arthralgia in traditional Chinese medicine.Its primary therapies include clearing heat and detoxification,activating blood circulation,and removing blood stasis.Lonicera japonica flos(LJF)has long been known as an excellent antipyretic and antidote.Luteoloside(Lut)is one of the main components of LJF and exhibits antioxidant,anti-inflammatory,and cytoprotective properties.However,the protection of Lut against iron overload injury and its underlying mechanisms remain unclear.Therefore,HUVECs were exposed to 50μmol·L^(−1)iron dextran for 48 h to establish an iron overload damage model and the effects of Lut were assessed.Our results showed that 20μmol·L^(−1)Lut not only increased cell viability and weakened LDH activity,but also significantly up-regulated DDAHⅡexpression and activity,increased p-eNOS/eNOS ratio and NO content,and reduced ADMA content in HUVECs exposed to iron overload.Furthermore,Lut significantly attenuated intracellular/mitochondrial ROS generation,improved SOD,CAT,and GSH-Px activities,reduced MDA content,maintained MMP,inhibited mPTP opening,prevented cyt c from mitochondria released into cytoplasm,reduced cleaved-caspase3 expression,and ultimately decreased cell apoptosis induced by iron overload.The effects of Lut were similar to those of L-arginine(an ADMA competitive substrate),cyclosporin A(a mPTP blocker agent),and edaravone(a free radical scavenger)as positive controls.However,addition of pAD/DDAHⅡ-shRNA adenovirus reversed the above beneficial effects of Lut.In conclusion,Lut can protect HUVECs against iron overload injury via the ROS/ADMA/DDAHⅡ/eNOS/NO pathway.The mitochondria are the target organelles of Lut’s protective effects.