Ginkgo biloba extract (GbE) enhances the anti-atherogenic effect of cilostazol by inhibiting ROS generation.

In this study, the synergistic effect of 6-[4-(1-cyclohexyl- 1H-tetrazol-5-yl) butoxy]-3,4-dihydro-2(1H )-quinolinone (cilostazol) and Ginkgo biloba extract (GbE) was examined in apolipoprotein E (ApoE) null mice. Co-treatment with GbE and cilostazol synergistically decreased reactive oxygen species (ROS) production in ApoE null mice fed a high-fat diet. Co-treatment resulted in a significantly decreased atherosclerotic lesion area compared to untreated ApoE mice. The inflammatory cytokines and adhesion molecules such as monocyte chemoattractant-1 (MCP-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), and VCAM-1 which can initiate atherosclerosis were significantly reduced by the co-treatment of cilostazol with GbE. Further, the infiltration of macrophages into the intima was decreased by co-treatment. These results suggest that co-treatment of GbE with cilostazol has a more potent anti-atherosclerotic effect than treatment with cilostazol alone in hyperlipidemic ApoE null mice and could be a valuable therapeutic strategy for the treatment of atherosclerosis.

Anti-inflammatory and analgesic activities of SKLJI, a highly purified and injectable herbal extract of Lonicera japonica.

The parenteral route has many merits over the oral route, including greater predictability, reproducibility of absorption, and rapid drug action, but injectable phytomedicines are uncommon due to protein precipitating tannin and hemolytic saponin components. In this study, in an effort to develop a safe injectable analgesic phytomedicine, we prepared a tannin and saponin-free Lonicera japonica extract, SKLJI, through fractionation and column purification, and evaluated its anti-inflammatory and analgesic activities in in vivo experimental models of inflammation and pain. The removal of tannin and saponin resulted in loganin and sweroside-enriched SKLJI and it showed reduced hemolysis and protein precipitation. In efficacy tests, SKLJI inhibited croton oil- and arachidonic acid-induced ear edema, acetic acid-induced writhing, and carrageenan-induced rat hind paw hyperalgesia. Inhibition of cylcooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and 5-lipoxyfenase (5-LO) activities by SKLJI appeared to be the mechanism underlying anti-inflammatory and analgesic efficacy. Loganin and sweroside also showed anti-inflammatory and analgesic activities, suggesting that they might be active principles in the efficacy of SKLJI. These results suggest that SKLJI is a viable candidate for a new anti-inflammatory and analgesic phytomedicine that can be administered by the parenteral route.

Enhancement of gastric ulcer healing and angiogenesis by cochinchina Momordica seed extract in rats.

Cochinchina momordica seed is the dried ripe seed of Momordica cochinchinensis, a perennial vine. The antiulcer effect of an extract from cochinchina momordica seeds (SK-MS10) was evaluated in a rat model of acetic acid-induced gastric ulcers. Gastric ulcers were produced by subserosal injection of acetic acid. SK-MS10 (200 mg/kg) or vehicle was administered orally once per day for 14 days after the acetic acid injection. The stomach was removed and the ulcer size measured at day 7 and 14 of the treatment. Expression of vascular endothelial growth factor (VEGF) was assessed by real-time RT-PCR and Western blot analysis. In addition, the microvasculature density (MVD) adjacent to the ulcer margin was examined by immunohistochemistry. The treatment with SK-MS10 for 7 and 14 days significantly accelerated ulcer healing and increased the expression of mRNA (at day 7) as well as VEGF protein (at day 14) compared to the vehicle-treated rats. The MVD for factor VIII was also higher in the SK-MS10 treatment group compared to the vehicle-treated rats; however, these differences were not statistically significant. These results suggest that SK-MS10 treatment accelerates the healing of gastric ulcers via upregulation of VEGF and angiogenesis in an acetic acid rat model.

Ginkgo biloba extract enhances antiplatelet and antithrombotic effects of cilostazol without prolongation of bleeding time.

Thrombosis and thromboembolic occlusions of major and minor blood vessels are a major complication in various peripheral vascular diseases. Antiplatelet agents (APA), key tools in the treatment of atherothrombosis, therefore became a mainstay medication for a wide range of vascular diseases. Cilostazol and Ginkgo biloba extract (GB), commonly used remedies for peripheral arterial disease, inhibit platelet aggregation with distinct therapeutic mechanisms. In this study, we have investigated if GB can potentiate the antiplatelet effects of cilostazol to explore the utility of combination therapy of cilostazol and GB against peripheral occlusive vascular diseases. GB or cilostazol was evaluated alone or in combination for the antiplatelet activity using in vitro and in vivo models. In addition, potential bleeding side effect of the combinative therapy was assessed by measuring bleeding time, prothrombin time (PT) and activated partial thromboplastin time (aPTT) in vivo after oral administration. In in vitro assays using freshly isolated human platelets, the combination of cilostazol and GB showed superior inhibition of both the shear and the collagen-induced platelet aggregation to those of each drug alone. In accordance with these enhanced in vitro antiplatelet activities, the combinative therapy showed enhanced anti-thrombotic effects in in vivo pulmonary embolism model and arterial thrombosis model. In particular, the increase of survival rate in pulmonary embolism model by combination treatment of cilostazol (25 mg/kg) and GB (20 mg/kg) was higher more than two-fold of those of the respective drugs. Notably, the combination of cilostazol and GB did not show a significant effect on the bleeding time, PT and aPTT increase, suggesting that GB may potentiate the antiplatelet effect of cilostazol without the prolongation of bleeding time or coagulation time. With these studies, we suggest that combinative therapy of GB and cilostazol might offer enhanced anti-thrombotic efficacies without increasing side-effects.

Gastroprotective action of Cochinchina momordica seed extract is mediated by activation of CGRP and inhibition of cPLA(2)/5-LOX pathway.

Cochinchina momordica seed extract (SKMS10), which is composed of the major compounds momordica saponins, has been evaluated for its gastroprotective effects in rat models of acute gastric mucosal damage. Ethanol and water immersion restraint stress (WRS) induced gastric damage, including hemorrhages and edema, was significantly attenuated by pretreatment with SK-MS10. In addition, SK-MS10 reduced increases of mucosal myeloperoxidase (MPO), IL-1ß, and TNFα levels and the expression of cPLA(2), and 5-LOX induced by ethanol or WRS. SK-MS10 also increased hexosamine, adherent mucus, and the expression of MUC5AC. Furthermore, SK-MS10 enhanced the mucosal expression of the CGRP gene and its serum levels.N(G)-methyl L-arginine (L-NMMA) or capsaicin desensitization reversed the SK-MS10-induced gastroprotection effect. These results suggest that SK-MS10 is a gastroprotective agent against acute gastric mucosal damage by suppressing proinflammatory cytokines, downregulating cPLA(2), 5-LOX, and increasing the synthesis of mucus. Furthermore, CGRP-NO pathway was found to play an important role in these gastroprotective effects of SK-MS10.

LC-MS/MS method for determination of hederacolchiside E, a neuroactive saponin from Pulsatilla koreana extract in rat plasma for pharmacokinetic study.

A simple, rapid, and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was applied to pharmacokinetic study of a neuroactive oleanolic-glycoside saponin, hederacolchiside E from SK-PC-B70M, a standardized extract of Pulsatilla koreana in rat. Rat plasma samples were pretreated by protein precipitation with acetonitrile, eluted from C(18) column, and analyzed using electrospray ionization (ESI)-MS/MS in negative ion mode. Digoxin was used as an internal standard. The standard curves were linear (r>0.997) over the concentration ranges of 2-500 ng/mL. The intra- and inter-day precisions were measured to be below 9% and accuracy between 90 and 111% for all quality control samples at 2, 20, 100, and 500 ng/mL (n=5). The lower limits of quantification (LLOQ) for hederacolchiside E was 2 ng/mL and the limit of detection (LOD) 0.5 ng/mL using 20 microL of plasma sample. Subsequently, hederacolchiside E was determined in rat plasma samples after oral administration of SK-PC-B70M. The mean maximum plasma concentrations of hederacolchiside E were 0.07, 0.13, and 0.36 microg/mL and the mean areas under the plasma concentration versus time curve 0.56, 1.27, and 6.46 microg h/mL at doses of 100, 200, and 400 mg/kg, respectively, which indicated non-linear pharmacokinetic pattern. In conclusion, this method was successfully applied to the pharmacokinetic study of hederacolchiside E after an oral administration of SK-PC-B70M to rats.