Salvianolic acid A inhibits calpain activation and eNOS uncoupling during focal cerebral ischemia in mice.

BACKGROUND: Salvianolic acid A (SAA) is obtained from Chinese herb Salviae Miltiorrhizae Bunge (Labiatae), has been reported to have the protective effects against cardiovascular and neurovascular diseases. HYPOTHESIS: The aim of present study was to investigate the relationship between the effectiveness of SAA against neurovascular injury and its effects on calpain activation and endothelial nitric oxide synthase (eNOS) uncoupling. STUDY DESIGN: SAA or vehicle was given to C57BL/6 male mice for seven days before the occlusion of middle cerebral artery (MCAO) for 60min. METHODS: High-resolution positron emission tomography scanner (micro-PET) was used for small animal imaging to examine glucose metabolism. Rota-rod time and neurological deficit scores were calculated after 24h of reperfusion. The volume of infarction was determined by Nissl-staining. The calpain proteolytic activity and eNOS uncoupling were determined by western blot analysis. RESULTS: SAA administration increased glucose metabolism and ameliorated neuronal damage after brain ischemia, paralleled with decreased neurological deficit and volume of infarction. In addition, SAA pretreatment inhibited eNOS uncoupling and calpain proteolytic activity. Furthermore, SAA inhibited peroxynitrite (ONOO-) generation and upregulates AKT, FKHR and ERK phosphorylation. CONCLUSION: These findings strongly suggest that SAA elicits a neurovascular protective role through the inhibition of eNOS uncoupling and ONOO- formation. Moreover, SAA attenuates spectrin and calcineurin breakdown and therefore protects the brain against ischemic/reperfusion injury.

Myrislignan attenuates lipopolysaccharide-induced inflammation reaction in murine macrophage cells through inhibition of NF-κB signalling pathway activation.

Myrislignan is a new kind of lignan isolated from Myristica fragrans Houtt. Its antiinflammatory effects have not yet been reported. In the present study, the antiinflammatory effects and the underlying mechanisms of myrislignan in lipopolysaccharide (LPS)-induced inflammation in murine RAW 264.7 macrophage cells were investigated. Myrislignan significantly inhibited LPS-induced production of nitric oxide (NO) in a dose-dependent manner. It inhibited mRNA expression and release of interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α). This compound significantly inhibited mRNA and protein expressions of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) dose-dependently in LPS-stimulated macrophage cells. Further study showed that myrislignan decreased the cytoplasmic loss of inhibitor κB-α (IκB-α) protein and the translocation of NF-κB from cytoplasm to the nucleus. Our results suggest that myrislignan may exert its antiinflammatory effects in LPS-stimulated macrophages cells by inhibiting the NF-κB signalling pathway activation.

Pyranocoumarins isolated from Peucedanum praeruptorum Dunn suppress lipopolysaccharide-induced inflammatory response in murine macrophages through inhibition of NF-κB and STAT3 activation.

Praeruptorin C, D, and E (PC, PD, and PE) are three pyranocoumarins isolated from the dried root of Peucedanum praeruptorum Dunn of Umbelliferae. In the present study, we investigated the anti-inflammatory effect of these compounds in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. Pyranocoumarins significantly inhibited LPS-induced production of nitric oxide, interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). The mRNA and protein expressions of inducible nitric oxide synthase, IL-6, and TNF-α were also suppressed by these compounds. Both PD and PE exhibited greater anti-inflammatory activities than PC. Further study showed that pyranocoumarins suppressed the cytoplasmic loss of inhibitor κB-α protein and inhibited the translocation of NF-κB from cytoplasm to nucleus. In addition, pyranocoumarins suppressed LPS-induced STAT3 tyrosine phosphorylation. Taken together, the results suggest that pyranocoumarins may exert anti-inflammatory effects in LPS-stimulated RAW 264.7 macrophages through the inhibition of NF-κB and STAT3 activation.

[The enhancing effect of Angelica dahurica extracts on absorption of baicalin--the active composition of Scutellaria].

To explore the mechanism of the absorption enhancement of Angelica dahurica extract (Ade), the absorption mechanism of baicalin in the Scutcllaria water extraction as well as the effect of Angelica dahurica extract on absorption of baicalin were investigated. In order to determine the main absorption site, everted intestinal sac model was used to study the effect of Angelica dahurica extract on the absorption of baicalin at duodenum, jejunum, ileum and colon. In situ single pass intestinal perfusion model was performed to study the absorption of various concentrations of baicalin and the effect of Angelica dahurica extract on the absorption of baicalin at the main absorption site. To authenticate the consequence of perfusion by getting the blood from the hepatic portal vein and determine the concentration of the baicalin in the blood. The result showed that baicalin could be absorbed at all of the four intestinal segments with increasing absorption amount per unit as follows: ileum > colon > jejunum > duodenum. The absorption ofbaicalin in the duodenum significantly increased with Angelica dahurica extract, thus, duodenum was chosen to be the studying site. Apparent permeability values (Papp) and absorption rate constant (Ka) of baicalin in the duodenum increased gradually with higher concentrations. When the concentration of baicalin rises to a certain degree, the absorption increase had a saturable process, the absorption of baicalin may be an active transportation. Baicalin may be not a substrate of P-gp as verapamil which had not significantly affected the Papp and Ka of baicalin. The absorption of baicalin in the duodenum significantly increased (P < 0.01) in the two models with Angelica dahurica extract and the concentration of baicalin in the blood from the hepatic portal vein showed that the Angelica dahurica extract can increase the absorption of baicalin.

Praeruptorin A inhibits lipopolysaccharide-induced inflammatory response in murine macrophages through inhibition of NF-κB pathway activation.

Praeruptorin A (PA) is a pyranocoumarin compound isolated from the dried root of Peucedanum praeruptorum Dunn (Umbelliferae). However, the antiinflammatory effect of PA has not been reported. The present study investigated the antiinflammatory effect of PA in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. PA significantly inhibited the LPS-induced production of nitric oxide (NO), interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α). The mRNA and protein expressions of inducible nitric oxide synthase (iNOS), IL-1ß and TNF-α were also suppressed by this compound. Further study showed that PA decreased the cytoplasmic loss of inhibitor κB-α (IκB-α) protein and inhibited the translocation of NF-κB from cytoplasm to nucleus. Taken together, the results suggest that PA may exert antiinflammatory effects in vitro in LPS-stimulated RAW 264.7 macrophages through inhibition of NF-κB signal pathway activation.

Correlation between synergistic action of Radix Angelica dahurica extracts on analgesic effects of Corydalis alkaloid and plasma concentration of dl-THP.

AIM OF STUDY: Yuanhu Zhitong prescription that consists of Corydalis yanhusuo and Radix Angelicae dahuricae has been used for the treatment of gastralgia, costalgia, headache and dysmenorrhea in Traditional Chinese Medicine. Our previous studies demonstrated that Corydalis alkaloid (CA, derived from the root of Corydalis yanhusu) had potent analgesic properties, and the total coumarins of Angelica dahurica (Cou) and volatile oil (VO) that derived from the root of Radix Angelicae dahuricae all could increase the analgesic effect of CA. The major objective of this paper was to investigate the mechanism that leading the analgesia of CA increased by Cou and (or) VO. MATERIALS AND METHODS: The relationship between analgesic effect of CA and the plasma concentration of Dl-tetrahydropalmatine (dl-THP, active component of CA) was assayed in mice writhing test. The CA (34, 68 and 134 mg/kg) reduced the nociception by acetic acid intraperitoneal injection in a dose-dependent manner, and there was a significant linear relationship between the analgesic effect of CA and the plasma concentration of dl-THP. Then the plasma concentration of dl-THP at different time intervals in rats after oral administration of CA, CA-Cou, CA-VO and CA-Cou-VO were examined by using HPLC. RESULTS AND CONCLUSION: The results indicated that Cou and (or) VO raised the plasma concentration of dl-THP prominently. In conclusion, the reason that Radix Angelica dahurica extracts reinforced the analgesic effects of Corydalis alkaloid was related to the improvement of the plasma concentration of dl-THP.

Effect of astragaloside IV on hepatic glucose-regulating enzymes in diabetic mice induced by a high-fat diet and streptozotocin.

AIM: Hepatic glycogen phosphorylase (GP) and glucose-6-phosphatase (G6Pase) are important in control of blood glucose homeostasis, and are considered to be potential targets for antidiabetic drugs. Astragaloside IV has been reported to have a hypoglycemic effect. However, the biochemical mechanisms by which astragaloside IV regulates hepatic glucose-metabolizing enzymes remain unknown. The present study examines whether GP and G6Pase mediate the hypoglycemic effect of astragaloside IV. METHODS: Type 2 diabetic mice were treated with astragaloside IV for 2 weeks. Blood glucose and insulin levels were measured by a glucometer and the ELISA method, respectively. Total cholesterol (TC) and triglyceride (TG) levels were determined using Labassay kits. Activities of hepatic GP and G6Pase were measured by the glucose-6-phosphate dehydrogenase-coupled reaction. The mRNA and protein levels of both enzymes were determined by real-time RT-PCR and Western blotting. RESULTS: Astragaloside IV at 25 and 50 mg/kg significally decreased the blood glucose, TG and insulin levels, and inhibited the mRNA and protein expression as well as enzyme activity of GP and G6Pase in diabetic mice. CONCLUSIONS: Astragaloside IV exhibited a hypoglycemic effect in diabetic mice. The hypoglycemic effect of this compound may be explained, in part, by its inhibition of hepatic GP and G6Pase activities.

[Comparison of microwave-assisted and conventional extraction of Corydalis yanhusuo].

OBJECTIVE: To compare the extraction yield and economic cost in the microwave-assisted extraction and conventional extraction of Corydalis yanhusuo. METHODS: Both of the extractions of Corydalis yanhusuo were optimized by orthogonal design. The contents of tetrahydropalmatine and total alkaloids were determined by HPLC and ultraviolet spectrophotometer, respectively. Meanwhile, the electricity consumption was determined in the extraction process. RESULTS: Comparing with conventional extraction, the microwave-assisted extraction saved time and money, and provided higher extraction yield of tetrahydropalmatine and total alkaloids. CONCLUSION: The microwave-assisted extraction has advantages in high efficiency and low cost.

[Influence of combination of extractum Angelicae Dahuricae Siccum and total alkaloids of Rhizoma Corydalis on pharmacokinetics of tetrahydropalmatine in rats].

This paper is aimed to develop a rapid and sensitive HPLC-fluorescence detection (FLD) method for the determination of tetrahydropalmatine (TET) in rats' plasma. The influence of combinations of Extractum Angelicae Dahuricae Siccum (coumarin and volatile oil) and total alkaloids (TA) from Rhizoma Corydalis (TA) on pharmacokinetics of TET in rats was studied. Plasma samples were treated with hexane-isopropanol (95:5) to precipitate the protein, and were determined by HPLC-fluorescence detection. The calibration curve was linear in the range of 2.096-167.68 microg L(-1). The limit of quantification was 2.096 microg L(-1). The method recovery of TET was 94.0%-100.0%. The extract recovery was 72.0%-81.5%. RSDs ofintra- and inter-day precisions were all less than 7.0%. Pharmacokinetics of TET in rats was fitted to two compartments open model after oral administration of TA, TA-volatile oil (VO), TA-coumarin (Cou) and TA-VO-Cou. Compared with TA, AUC(0-t), AUC(0-infinity), MRT(0-t), and MRT(0-infinity) of TET had significant deviation when combined with VO and/or Cou. The determination method is sensitive, specific, accurate, and appropriate for determination of TET in vivo. Coumarin and/or VO combined with TA can prolong the resistance time of TET significantly, delay elimination and enhance bioavailability of tetrahydropalmatine.

Ellagitannin (BJA3121), an anti-proliferative natural polyphenol compound, can regulate the expression of MiRNAs in HepG2 cancer cells.

MicroRNAs (miRNAs) play an important role in cancers. A number of miRNA expression-profiling studies have been done to identify the miRNA signatures of cancers from different cellular origin. There is, however, relatively little information on how anticancer agents regulate miRNA expression. Ellagitannin (BJA3121), 1,3-Di-O-galloyl-4,6-(s)-HHDP-b-D-glucopyranose, is a new natural polyphenol compound isolated from Balanophora Japonica MAKINO. Our preliminary results have shown that BJA3121 had antiproliferative effect and modified the expression of different genes in human HepG(2) cancer cells. In this study, we further evaluate whether this antineoplastic compound is able to alter miRNA expression in HepG(2) cells. We demonstrated for the first time that BJA3121 can regulate the expression of 25 miRNAs, including 17 upregulated and 8 downregulated miRNAs in HepG(2) cells. Our results suggested that BJA3121-modifed miRNA expression can mediate, at least in part, the antiproliferative and multigene regulatory action induced by the compound on HepG(2) cancer cells.