Qian-Ping Shi

Neuroprotective effects of scutellarin and scutellarein on repeatedly cerebral ischemia-reperfusion in rats.

Scutellarin had protective effects against neuronal injury, however, there are few studies on the protective effect of scutellarein, which is the main metabolite of scutellarin in vivo. This study investigated whether the neural injury by ischemia/reperfusion would be influenced by different doses of scutellarin and scutellarein. Male Wistar rats were orally administered with scutellarin and scutellarein at the doses of 0.09, 0.17, 0.35, 0.70, 1.40 mmol/kg, respectively; then after six consecutive days, they were subjected to global ischemia by occlusion of the bilateral common carotid arteries (BCCAO). After reperfusion for about 21 h, neurological and histological examinations were performed. The present results showed that scutellarein attenuated neuronal cell damage, reduced cerebral water content, regulated the expression of glutamic acid (Glu), aspartic acid (Asp), glycine (Gly), γ-aminobutyric acid (GABA) and taurine (Tau), and improved the Ca(2+)-ATPase and Na(+),K(+)-ATPase activity. Meanwhile, significant difference was found among various doses of scutellarin and scutellarein. Our studies indicated that scutellarin and scutellarein could improve neuronal injury, and scutellarein had better protective effect than scutellarin in rat cerebral ischemia.

Mannich bases of scutellarein as thrombin-inhibitors: Design, synthesis, biological activity and solubility

Two series of 8-aminomethylated derivatives were prepared by Mannich reaction of scutellarein (2) with appropriate aliphatic amines, alicyclic amines and formaldehyde. All the compounds were tested for their thrombin inhibition activity through the analyzation of prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT) and fibrinogen (FIB). The antioxidant activities of these target products were assessed by 1,1-diphenyl-2-picrylhydrazyl radical 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH) assay using 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) assay method and the solubility were assessed by ultraviolet (UV). The results showed that morpholinyl aminomethylene substituent derivative (3d) demonstrated stronger anticoagulant activity, better water solubility and good antioxidant activity compared with scutellarein (2), which warrants further development as a agent for ischemic cerebrovascular disease treatment.

Design, synthesis and biological evaluation of glucose-containing scutellarein derivatives as neuroprotective agents based on metabolic mechanism of scutellarin in vivo

Based on metabolic mechanism of scutellarin in vivo that scutellarin could be hydrolyzed into scutellarein by β-glucuronide enzyme, some glucose-containing scutellarein derivatives were designed and synthesized through the introduction of glucose moiety at C-7 position of scutellarein via a glucosidic bond. Biological activity evaluation showed that these glucose-containing scutellarein derivatives exhibited potent DPPH radical scavenging activities. Furthermore, the improvement of physicochemical properties such as anticoagulant and neuroprotective activities alongside with the water solubility was achieved by introducing glucose. These findings suggest that the introduction of the glucose moiety to scutellarein wattants further development of this kind of compounds as neuroprotective agents.

Synthesis and Protective Effect of Scutellarein on Focal Cerebral Ischemia/Reperfusion in Rats

Scutellarein, the main metabolite of scutellarin in vivo, has relatively better solubility, bioavailability and bio-activity than scutellarin. However, compared with scutellarin, it is very difficult to obtain scutellarein from Nature. Therefore, the present study focused on establishing an efficient route for the synthesis of scutellarein by hydrolyzing scutellarin. Neurological deficit score and cerebral infarction volume with the administration of scutellarein were then used to compare its neuroprotective effects on focal cerebral ischemia/reperfusion in rats induced by middle cerebral artery occlusion (MCAO) with those of scutellarin. The results showed that scutellarein had better protective effect on focal cerebral ischemia/reperfusion than scutellarin, which laid the foundation for further research and development of scutellarein as a promising candidate for ischemic cerebro-vascular disease.

Synthesis and structure–activity relationship analysis of caffeic acid amides as selective matrix metalloproteinase inhibitors

Four series of acid amides were synthesized, and through measurement using a fluorogenic substrate assay with human recombinant MMP-1, MMP-2 and MMP-9, compound 3f showed considerable inhibitory activities against MMP-2, MMP-9 and the best selectivity over MMP-1. Preliminary structure-activity relationship analysis indicated that caffeic acid amides with electron-donating groups at para-position of amino phenyl group showed better inhibitory activities and selectivity than those with electron-withdrawing groups, and the presence of adjacent dihydroxy in the caffeoyl group was very important for the MMP-2 and MMP-9 inhibitory activities.

Design, Synthesis, and Preliminary Evaluation of Substituted Cinnamic Acid Esters as Selective Matrix Metalloproteinase Inhibitors

Strategy, Management and Health Policy Preclinical Research

Comparative Metabolomic Analysis of the Neuroprotective Effects of Scutellarin and Scutellarein against Ischemic Insult.

For more than thirty years, scutellarin (Scu) has been used in China to clinically treat acute cerebral infarction and paralysis. Scutellarein (Scue), the major Scu metabolite in vivo, exhibits heightened neuroprotective effects when compared to Scu. To explore the neuroprotective role of these compounds, we performed ultra-high-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry (UHPLC-QTOF/MS) coupled with a pattern recognition approach to investigate metabolomic differences in a rat model of ischemia after treatment with each compound. We examined metabolites in urine, hippocampal tissue, and plasma, and we tentatively identified 23 endogenous metabolites whose levels differed significantly between sham-operated and model groups. Upon pathway analysis, we found an additional 11 metabolic pathways in urine, 14 metabolic pathways in the hippocampal tissue, and 3 metabolic pathways in plasma. These endogenous metabolites were mainly involved in sphingolipid metabolism, lysine biosynthesis, and alanine, aspartate, and glutamate metabolism. We found that metabolic changes after ischemic injury returned to near-normal levels after Scue intervention, unlike Scu treatment, further validating the heightened protective effects exerted by Scue compared to Scu. These results demonstrate that Scue is a potential drug for treatment of ischemic insult.

Design, Synthesis and Biological Evaluation of Caffeic Acid Amides as Selective MMP‐2 and MMP‐9 Inhibitors

Strategy, Management and Health Policy Preclinical Research

Synthesis of scutellarein derivatives to increase biological activity and water solubility.

In order to improve the biological activity and water solubility of scutellarin (1), some derivatives of its main metabolite (scutellarein) were designed and synthesized. All the compounds were tested for their thrombin inhibition activity through the analyzation of thrombin time (TT), activated partial thromboplastin time (APTT), prothrombin time (PT) and fibrinogen (FIB). Their antioxidant activities were assessed by measuring their scavenging capacities toward 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and the ability to protect PC12 cells against H2O2-induced cytotoxicity, their water solubility were also assessed by ultraviolet (UV) spectrophotometer. The results showed that compound 8b demonstrated stronger anticoagulant and antioxidant activity, better water solubility compared with scutellarein (2), which warrants it as a promising agent for the treatment of ischemic cerebrovascular disease.

Biological evaluation and SAR analysis of O-methylated analogs of quercetin as inhibitors of cancer cell proliferation.

Preclinical Research