Objective To design and synthesize derivatives of oleanolic acid and ursolic acid, and investigate their anti-hepatitis C virus （HCV） activity along with that of common triterpenoid acids. To explore the structure-activity relationship and provide a reference for the research of anti-HCV drugs derived from natural products through obtaining compounds with higher activity. Methods Oleanolic acid and ursolic acid were directly reacted with corresponding amines using PyBOP as a condensing agent in the presence of DIEA. Alternatively, the target compounds were prepared through PCC oxidation followed by the Baeyer-Villiger reaction catalyzed by m-CPBA. In vitro anti-HCV activity was tested using the HCVcc infection model. Molecular docking was performed by Autodock software to investigate the interaction between the active compounds and HCV NS5B. Results Oleanolic acid, glycyrrhetinic acid, ursolic acid, and asiatic acid all exhibited certain anti-HCV effects. Specifically, oleanolic acid derivatives OA2-OA4, OA6, and OA7, as well as ursolic acid derivatives UA1 and UA2, demonstrated superior anti-HCV activity compared to their parent compounds. Preliminary structure-activity relationship analysis revealed that introducing a bulky group to 28-COOH of oleanolic acid and ursolic acid enhanced their activity. Molecular docking results demonstrated that the active compounds could stably bind to HCV NS5B, thereby exhibiting antiviral activity. Conclusion Pentacyclic triterpenoids possessed anti-HCV effects, and their derivatives coud be synthesized to obtain more active compounds. The anti-HCV mechanism of these compounds may be associated with their inhibition of NS5B.

BACKGROUND: Bistort rhizome is also named as caoheche, which is characterized by clearing heat, relieving convulsion, regulating damp and reducing swelling. Additionally, its water extract is characterized by antiarrhythmia and central inhibition; however, analgesia should be studied further.OBJECTIVE: To observe analgesic effect of polygonum bistorta L. Water extract, and compare with morphine and amidazofen.DESIGN: Completely randomized digital table and randomized controlled animal study.SETTING: Department of Pharmacology, Gannan Medical College.MATERIALS: The experiment was carried out in the Laboratory of Scientific Center of Gannan Medical College from March to May 2004. ① A total of 150 healthy adult Kunming mice were used in the 4 independent experiments. ② Medicines: Polygonum bistorta L. Water extract (Department of Phytochemistry, Shenyang Pharmaceutical University; batch number: 2003061001); morphine hydrochloride solution (Shenyang First Pharmaceutical Factory; batch number: 000305); naloxone hydrochloride solution (Yanqiao pharmaceutical Co. Ltd.; batch number: 20021109).METHODS: ① Effect of polygonum bistorta L. Water extract on twisting-body reaction of mice induced by acetic acid: Forty mice were randomly divided into 4 groups: saline group, 0.10 and 0.15 mg/g polygonum bistorta L. Water extract groups and amidazofen group with 10 in each group. All mice were intraperitoneally injected with 0.02 mL/g saline,0.10 and 0.15 mg/g polygonum bistorta L. Water extract solution and 0.10 mg/g amidazofen, respectively. Fifteen minutes later, mice were intraperitoneally injected with 6 g/L 0.01 mL/g acetic acid glacial to record times of twisting-body reaction within 15 minutes. ② Effect of polygonum bistorta L. Water extract on pain response of mice induced by hot-plate test: Forty female mice were randomly divided into 4 groups:saline group, 0.10 and 0.15 polygonum bistorta L. Water extract groups and morphine group with 10 in each group. All mice were intraperitoneally injected with 0.02 mL/g saline, 0.10 and 0.15 mg/g polygonum bistorta L. Water extract solution and 0.01 mg/g morphine solution, respectively. GJ-8402 hot-plate pain response threshold detector was used in this study; pain response temperature was (55.0±0.5) ℃; pain response after licking hindfoot was regarded as reactive marker; latency of pain response threshold was within 60 s. Pain response was measured at 15, 30 and 60 minutes after administration with hot-plate test. ③ Effect of morphine, naloxone and polygonum bistorta L. Water extract on pain response of mice induced by hot-plate test: Thirty female mice were randomly divided into 3 groups: saline group, naloxone+morphine group and naloxone+polygonum bistorta L. Water extract group with 10 in each group. All mice were intraperitoneally injected with 0.02 mL/g saline, 0.004 mg/g naloxone solution+0.01 mg/g morphine solution and 0.004 mg/g naloxone solution+0.15 mg/g polygonum bistorta L. Water extract solution, respectivelu. Pain response was measured at 15, 30 and 60 minutes after administration with hot-plate test. ④ Effect of polygonum bistorta L. Water extract on pain response of mice induced by electric stimulation: Forty mice were randomly divided into 4 groups with 10 in each group. All mice were intraperitoneally injected with 0.02 mL/g saline, 0.10 and 0.15 mg/g polygonum bistorta L. Water extract and 1 g/L morphine, respectively. Pain response was measured at 20, 35, 50 and 70 minutes after administration with electric stimulus method.MAIN OUTCOME MEASURES: ① Times of twisting-body reaction; ②duration of pain response induced by hot-plate test; ③ analgesic rate induced by electric stimulation.RESULTS: All 150 healthy adult Kunming mice were involved in the final analysis. ① Times of twisting-body reaction: At 15 inutes after administration, times of twisting-body reaction were less in 0.10 and 0.15 mg/g polygonum bistorta L. Water extract group and amidazofen group than those in saline group [(15.1±11.1), (8.0±6.5), (6.3±3.2), (54.1±20.2) times, t=3.532-3.681, P ＜ 0.01]. ② Duration of pain response induced by hot-plate test:At 15, 30 and 60 minutes after administration, durations of pain response induced by hot-plate test were longer in 0.10 and 0.15 mg/g polygonum bistorta L. Water extract group and morphine group than those in saline group (t=2.676-3.683, P ＜ 0.05-0.01). ③ Duration of pain response was longer in naloxone + polygonum bistorta L. Water extract group than that in saline group at each time point after administration (t=2.676-3.563, P＜ 0.05-0.01); however, duration in naloxone + morphine group was close to that in saline group (P ＞ 0.05). ④ Analgesic rate induced by electric stimulation: At 20, 35, 50 and 70 minutes after administration, analgesic rate induced by electric stimulation was higher in 0.10 and 0.15 mg/g polygonum bistorta L. Water extract group and morphine group than that in saline group (t=3.455-3.634, P ＜ 0.01).CONCLUSION: ① Polygonum bistorta L. Water extract has the obviously analgesic effect, whose intensity is close to that of amidazofen and morphine. ② Naloxone, an opiate receptor antagonist, can resist analgesic effect of morphine but not that of polygonum bistorta L. Water extract. This suggests that analgesic effect of polygonum bistorta L. Water extract dose not react through exciting opiate receptor.

Aim To investigate the inhibitory effects of xanthotoxol(XT) on neutrophil infiltration and brain edema induced by focal cerebral ischemia-reperfusion injury in rats.Methods Focal cerebral ischemia-reperfusion model in rat was induced by transient occlusion of the middle cerebral artery for 2 hours and followed by 24 hours of reperfusion.XT(2.5,5 and 10 mg?kg-1,ip)was administered at 1 hour and 12 hours after the onset of ischemia,respectively.After 24 hours of reperfusion,the influence of XT on neurological deficit score,brain edema and infarct size were evaluated;the activity of Na+,K+-ATPase,Ca2+-ATPase and myeloperoxidasse(MPO) in the ischemic hemisphere cortex of the middle cerebral artery area was assayed by spectrophotometry;the expression of intercellular adhesion molecule-1(ICAM-1) and E-selectin was measured with immunohistochemistry.Results XT significantly reduced the neurological deficit score,brain edema and infarct size,enhanced activity of Na+,K+-ATPase and Ca2+-ATPas,suppressed the injury-induced upregulation of MPO activity and cell adhesion molecules(ICAM-1 and E-selectin) expression in the brain tissue.Conclusion XT attenuates brain damage following focal cerebral ischemia-reperfusion in rats and its mechanism may partly be due to the inhibition of inflammation and brain edema induced by ischemia-reperfusion.