Scrophularia amplexicaulis increases anti-cancer potential of doxorubicin in gastric cancer cells

Increased drug resistance has reduced efficiency of chemotherapic drugs such as Doxorubicin (Dox). Scrophularia amplexicaulis (Scr) is one of the most important medicinal plants in Iran that has anti-cancer activity. The aim of this study was to investigate a novel approach to enhance therapeutic efficacy of Dox (as a chemotherapeutic agent) by co-administration of Scr (as a bioactive herbal compound) in gastric cancer treatment. In the present study, effects of Dox, Scr, and their combinations (Scr-Dox) were evaluated on viability and proliferation of two gastric cancer cell lines (AGS and MKN28). Moreover, morphological changes, invasion, migration, colony formation, and apoptosis rate in the treated cancer cells were evaluated. Expression of BAX, BCL2, SAMC, SURVIVIN, CASP9, P53, MMP9, and MMP2 in the treated cancer cells and untreated controls were evaluated by Real-Time PCR method. Treatments of cancer cells by Scr, Dox, and Scr-Dox significantly decreased proliferation, invasion, migration, and colony formation of gastric cancer cells. Treatments of cancer cells by Scr, Dox, and Scr-Dox significantly increased apoptosis rate as well as decreased cells mobility through modification of apoptosis- and metastasis-related genes expression. However, anti-cancer activity of Scr-Dox combination was significantly more than Scr and Dox treatments alone. In general, we demonstrated that Scr-Dox combination therapy exerts more profound anti-cancer effects on AGS and MKN28 cell lines than Scr and Dox monotherapy.

in response to drought stress

Plants respond to water shortage by regulating biochemical pathways which result in the biosynthesis of osmotic compounds. Active metabolites and compatible osmolytes control the inhibition of oxygen free radicals and dehydration. The physiological response of scrophularia striata to drought stress, a factorial completely randomized design (FCRD) experiment was conducted in three replication. Drought stress was induced at two levels (100% and 50% field capacity), and salicylic acid (SA) and silicon (Si) and Ecotype were also used at two levels of (0 and 100 PPM), (0 and 1 g/L) and (Ilam and Abdanan) respectively. Data analysis results indicated that the H2O2 content, Malondialdehyde (MDA), glycine betaine (GB) and the activity of the enzyme glutathione reductase (GR; EC 1.6.4.2) of aerial parts increased during the entire stress exposure period. Although the SA + Si + stress + ecotype interaction increased the content of soluble carbohydrate s and the GR activity in aerial parts of Ilam and Abdanan ecotypes, this interaction led to a decrease in MDA, H2O2 in Ilam ecotypes. The interaction between the stress + SA + Si + ecotype led to an increase in the phenylalanine ammonialyase (PAL; EC 4.3.1.5) activity in the Abdanan ecotype, but no important difference was observed. As compared to the control treatment, the content of Polyphenol increased, The interaction between ecotype + stress + Si caused to increased the of proline content in the Abadanan ecotype. The results showed that the increase in antioxidant defense and compatible osmolytes due to the use of SA and Si can improve the drought tolerance in S.striata.

Variations in Rhizospheric and Endophytic Root Fungal Communities of Scrophularia ningpoensis in Different Producing Areas

Few studies have examined the association of factors associated with soil fertility and composition with the structure of microbial communities in the rhizosphere and endosphere. Hence, this study aimed to explore the effects of geographical differences on fungal communities in the roots of Scrophularia ningpoensis and the relationship between the fungal communities and secondary metabolic components in the host plant. We found that there was greater diversity in the fungal communities of the rhizosphere compartment than in endosphere communities. Ascomycota and Basidiomycota were dominant among the endosphere fungi, whereas Mortierellomycota was distributed in the rhizosphere. The composition of bulk soil obtained from different producing areas was significantly different, and the correlation between the rhizospheric and physicochemical compartments of the soil was higher than that observed with the endophytic compartment. Redundancy analysis and canonical correspondence analysis of the rhizospheric and endophytic samples revealed that the organic matter, total organic carbon, total nitrogen, and Hg levels were adequately correlated with the composition of rhizospheric and endophytic fungal communities. Multiple linear regression analyses facilitated the identification of potentially beneficial fungi whose abundance was correlated with levels of secondary metabolites, such as harpagide and harpagoside. These fungi could potentially provide valuable information regarding the use of S. ningpoensis in the medicinal plant industry.

P2X7-Receptor Pathway Involvement in the Anti-Inflammatory Activity of Medicinal Plants

Medicinal plants used in European folk medicine attached to Lamiales, Gentianales or Asterales orders are used to treat inflammatory disorders. Many targets have been identified but to date, implication of purinergic receptor P2X7 activation has not yet been investigated. We managed to evaluate the protective effect on P2X7 activation by plant extracts used as anti-inflammatory in European folk medicine by the YO-PRO-1 uptake dye in vitro bioassay. Results revealed that among our selected plants, species from Scrophularia and Plantago genus were able to decrease significantly P2X7 activation (>50 % at 0.1 and 1 μg/mL). UPLC/MS, dereplication and metabolomic analysis of Scrophularia extracts, allowed us to identify the cinnamoyl-iridoid harpagoside as putative inhibitor of P2X7 activation. These results open a new research field regarding the anti-inflammatory mechanism of cinnamoyl-iridoids bearing plants, which may involve the P2X7 receptor.

Aqueous extract of Scrophularia ningpoensis improves insulin sensitivity through AMPK-mediated inhibition of the NLRP3 inflammasome

BACKGROUND

Scrophularia ningpoensis Hemsl. is a commonly used medicinal plant in China for the treatment of diabetes mellitus (DM), but its mechanism of action remains poorly described. Type 2 diabetes mellitus (T2DM) accounts for > 90% of all DM cases and is characterized by insulin resistance.

PURPOSE

The aim of this study was to investigate whether the insulin sensitivity can be improved by treatment with aqueous extract of S. ningpoensis (AESN) and further explore its mechanism(s) of activity.

METHODS

Primary mouse hepatocytes and human HepG2 hepatocytes were used to investigate the effects of AESN on cell viability, AMP-activated protein kinase (AMPK) activation and glucose output under normal culture conditions. To mimic hyperglycemia and insulin resistance in vitro, hepatocytes were exposed to high glucose (HG), and the influences of AESN on AMPK phosphorylation, NLRP3 inflammation activation, insulin signaling, lipid accumulation and glucose output were investigated. Increasing doses of AESN (50, 100 and 200 mg/kg/day) were administered by gavage to db/db mice for 8 weeks, and then biochemical analysis and histopathological examinations were performed.

RESULTS

AESN significantly activated AMPK and inhibited glucose output in hepatocytes, but did not impact cell viability under normal culture conditions. Moreover, in HG-treated hepatocytes, AESN protected against aberrant AMPK activity, NLRP3 inflammasome activation, insulin signaling, and lipid accumulation. AMPK inhibition abolished the regulatory effects of AESN on the NLRP3 inflammasome, insulin signaling, lipid accumulation, and glucose output of hepatocytes following HG exposure. Furthermore, AESN administration reduced blood glucose and serum insulin levels, improved lipid profiles and insulin resistance, and corrected the aberrant AMPK activity and NLRP3 inflammasome activation in liver tissues.

CONCLUSION

AESN improves insulin sensitivity via AMPK-mediated NLRP3 inflammasome inhibition.

Changes in phenolic compounds production as a defensive mechanism against hydrogen sulfide pollution in Scrophularia striata

Increasing pollutants such as hydrogen sulfide (H₂S) from industrial activities is an ecological challenge for plants, which seriously affects their health and productivity. Scrophularia striata is a plant endemic to Iran growing in the province of Ilam, wherein a gas refinery releases toxic agents such as H₂S whose detrimental effects on the function and tolerability of medicinal plants in this region have yet to be elucidated. Thus, we initiated a hydroponic study into hormetic effect of sodium hydrogen sulfide (NaHS) concentrations (0, 3 and 7 mM) as H₂S-donor at different time points on oxidative status and phenolic compounds, focusing more on phenylethanoid glycosides (PhGs) in S. striata. Our results indicated that hydrogen peroxide (H₂O₂) increased significantly at 3 mM NaHS after 48 h, while its peak at 7 mM occurred after 24 h. Nitric oxide (NO) level peaked at 3 mM and 7 mM after 24 h. Treatment with NaHS also resulted in a dose-dependent induction of phenylalanine ammonia-lyase (PAL) and tyrosine ammonia-lyase (TAL) enzyme activities, phenolic acids production (cinnamic acid, coumaric acid, ferulic acid, caffeic acid and salicylic acid) and acteoside accumulation, ultimately leading to an increase in antioxidant capacity. Modulation of soluble sugars contents including glucose, mannose and rhamnose/xylose, occurred after the treatment with NaHS, likely increasing plant tolerance due to their biological activity and structural effects. Overall, our results suggest that dose-dependent accumulation of phenolics, notably acteoside, leads to an augmentation in antioxidant system to deal with H₂S stress in S. striata.

Pharmacology, phytochemistry, and traditional uses of Scrophularia ningpoensis Hemsl

ETHNOPHARMACOLOGICAL RELEVANCE

Scrophularia ningpoensis Hemsl. (known as Xuanshen) has been used in China for centuries as a traditional medicinal plant to treat numerous diseases including inflammation, hypertension, cancer, and diabetes.

AIM OF REVIEW

In this review, we provide an update on the botany, pharmacology, phytochemistry, pharmacokinetics, traditional uses, and safety of S. ningpoensis to highlight future research needs and potential uses of this plant.

MATERIALS AND METHODS

All information on S. ningpoensis was obtained from scientific databases including ScienceDirect, Springer, PubMed, Sci Finder, China Knowledge Resource Integrated Database from the China National Knowledge Infrastructure (CNKI), Google Scholar, and Baidu Scholar. Additional information was collected from Chinese herbal medicine books, Ph.D. dissertations, and M.Sc. Theses. Plant taxonomy was verified by "The Plant List" database (http://www.theplantlist.org).

RESULTS

S. ningpoensis displays fever reducing, detoxifying, and nourishing 'Yin' effects in traditional Chinese medicine (TCM). More than 162 compounds have been identified and isolated from S. ningpoensis, including iridoids and iridoid glycosides, phenylpropanoid glycosides, organic acids, volatile oils, terpenoids, saccharides, flavonoids, sterols, and saponins. These compounds possess a diverse variety of pharmacological properties that affect the cardiovascular, hepatic, and nervous systems, and protect the body against inflammation, oxidation, and carcinogenesis.

CONCLUSIONS

Modern pharmacological studies have confirmed that S. ningpoensis is a valuable Chinese medicinal herb with many pharmacological uses in the treatment of cardiovascular, diabetic, and liver diseases. Most of the S. ningpoensis activity may be attributed to iridoid glycosides and phenylpropanoid glycosides; however, detailed information on the molecular mechanisms, metabolic activity, toxicology, and structure-function relationships of active components is limited. Further comprehensive research to evaluate the medicinal properties of S. ningpoensis is needed.

Synergistic nourishing 'Yin' effect of iridoid and phenylpropanoid glycosides from Radix Scrophulariae in vivo and in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

Radix Scrophulariae (RS), is a renowned traditional Chinese medicine used as nourishing 'Yin'. The iridoid glycosides (IG) and phenylpropanoid glycosides (PG) are main chemical constituents in RS. However, there had been no pharmacological experiment studies of synergy between IG and PG. Due to the constituents interactions, exploring their synergy profile is of great important for explaining the essence of nourishing 'Yin' efficacy of RS.

AIM OF STUDY

The present study was undertaken to evaluate synergistic nourishing 'Yin' effect of IG and PG from RS in vivo and in vitro through their immunoregulation and antioxidant activities.

MATERIALS AND METHODS

In this study, IG and PG fractions in RS were isolated and identified by High Performance Liquid Chromatography coupled with tandem quadrupole time-of-flight Mass Spectrometry (HPLC-Q-TOF-MS). The synergistic nourishing 'Yin' effect of two fractions were investigated in vivo and in vitro with thyroxine-induced 'Yin' deficiency (YD) mice model and primary splenic lymphocyte, respectively. The exterior syndrome signs and serologic and cellular biomarkers changes were detected. Then, the synergistic coefficient (SC) of IG and PG on every pharmacodynamics index were calculated by Webb method.

RESULTS

Compared with model and mono-therapy group (IG or PG group), IG combined with PG group significantly ameliorated YD by exerting immunoregulation and antioxidant effects. Based on the SC, IG and PG possessed a synergistic effect on heart rate, average speed, upright times, spleen index, LPO, SOD, IL-6, Na⁺-K⁺-ATP enzyme in vivo, and cAMP/cGMP, IFN-γ/IL-10, and MDA in vitro with SC > 1.

CONCLUSIONS

The nourishing 'Yin' benefits were clearly produced when IG and PG were used in combination, which provided the scientific evidence of multiple-components and multiple-approach synergistic effect of Chinese traditional herbal medicine to control and management of diseases.

Two new compounds from the roots of Scrophularia ningpoensis and their anti-inflammatory activities

Aiming to investigate the bioactive constituents with anti-inflammatory activity from the roots of Scrophularia ningpoensis, two new compounds (1 and 3) were isolated from the extract of the roots of the plant. Their structures were elucidated on the basis of spectral analyses (UV, IR, NMR, and MS spectroscopy), as well as experimental and calculated electronic circular dichroism (ECD) analyses. All of the isolates were tested for their anti-inflammatory properties in terms of suppressing the production of NO in lipopolysaccharide-induced BV2 cells. Compound 2 exhibited stronger anti-inflammatory effects (77.65%) than the positive control curcumin (69.75%) at 10 μM.

Clinical, in vitro and phytochemical, studies of Scrophularia striata mouthwash on chronic periodontitis disease

ETHNOPHARMACOLOGICAL RELEVANCE

Chronic periodontitis is an inflammatory process of the oral cavity that is caused by different reasons. Streptococcus mutans bacteria is the main cause of the disease. Scrophularia striata in Iranian traditional medicine is used to heal inflammation of gum and mouth. Also, In vitro anti-bacterial effect of S. striata in S. mutans have been demonstrated.

AIM OF THE STUDY

Clinical, in vitro and chemical constituent studies of S. striata on chronic periodontitis disease.

MATERIALS AND METHODS

This study is a randomized clinical trial that was performed in Dental College, Hamadan University of Medical Sciences. Fifty patients with chronic periodontitis (20-50 years old) were selected and the study was approved and registered in Iranian Registry of Clinical Trials as number IRCT2015081323468N1 prior to the experiment. The 50 patients were divided into two groups. One group used herbal mouthwash that was made from hydro alcoholic extract of S. striata and another group used Irsha mouthwash (Iranian form of Listerine mouthwash). Patients were followed up after two weeks and four weeks of using mouthwash for assessment of plaque index (PI), pocket depth (PD), bleeding on probing (BOP) and counting Streptococcus mutans. The mouthwash was standardized according to gallic acid, quercetin and apigenin reference using the RP-HPLC method. The total phenolic and flavonoids contents were also determined spectrophotometerically.

RESULTS

S. striata in the short term, improve plaque index, pocket depth and bleeding on probing but the number of Streptococcus mutans changed significantly in the long term and is more potent in comparison to Irsha mouthwash. The mouthwash was standardized according to gallic acid, quercetin and apigenin standard (3, 24, 11 μg, respectively). The total phenolic and flavonoid content of mouthwash were 120.7 μg GAE/100 cc and 78.6 μg QE/100 cc respectively.

CONCLUSIONS

S. striata mouthwash is effective in the treatment of chronic periodontitis disease and is more potent comparing the Iranian Irsha mouthwash.

[Optimization of drying process for Scrophulariae Radix by multivariate statistical analysis]

To establish the suitable modern drying processing parameters for Scrophulariae Radix (SR). With reference to the traditional drying processing method of SR and the characteristics of modern drying equipment, the drying process for SR was simulated as the following three stages: temperature-controlled drying-tempering-temperature-controlled drying. Eighteen batches of SR samples were obtained by the drying methods after the orthogonal design experiment with seven factors namely temperature, wind speed, and target moisture for the first stage, tempering time and temperature, as well as temperature and wind speed for the second stage. UPLC-TQ-MS was applied for determination of nine target compounds including catalpol, harpagide, verbascoside, ferulic acid, angroside-C, aucubin, harpagoside, cinnamic acid and ursolic acid in those dried samples and another 19 batches of SR samples collected from genuine producing area. Principal Component Analysis (PCA) was performed, and total energy consumption was also taken into consideration for analysis and evaluation. Results showed that the optimal drying processing method for SR was as follows: drying temperature of 60 ℃, drying wind speed of 50 Hz, and 50% for target moisture in the first stage; 24 h for tempering time and temperature of 20 ℃ in the second stage; drying temperature of 60 ℃, and drying wind speed of 30 Hz in the third stage. The medicinal materials with optimized modern drying processing method were extremely similar to those collected from genuine producing area in the aspect of both external properties and target compounds, and they were in line with the 2015 version of "Chinese Pharmacopoeia" requirements. In addition, they could help to shorten the drying time and increase the efficiency of primary processing, and thus promote the normalization and standardization of primary drying processing for SR.

[Species, Damage and Community Structure of Weeds in Scrophularia ningpoensis Fields in Nanchuan, Chongqing]

OBJECTIVE

To investigate the damage and community structure of weeds in Scrophularia ningpoensis fields in Nanchuan, Chongqing.

METHODS

From 2013 to 2014, an investigation was carried out by inverted W-9 point sampling method to study the weed species.

RESULTS

96 weed species belonged to 75 genera of 30 families were observed, including 18 species of Asteraceae weeds (accounted for 18.75%), 10 species of Poaceae weeds (accounted for 10.42%). Moreover, there were 57 species of annual weeds (accounted for 59.38%) and 39 species of perennial weeds (accounted for 40.63%). The overall abundance of Erigeron annuus, Digitaria adscendens, Torilis scabra, Polygonum nepalense, Ranunculus japonicas, Stellaria media and Commelina communis were relatively higher than that of the others.

CONCLUSION

The difference of weed species and community structure might result from the physical and chemical characteristics of soil, moisture content, cropping system, tillage type, environmental and climatic conditions, crop distribution and weed control.

[Chemical constituents of Scrophularia ningpoensis root]

OBJECTIVE

To investigate the chemical constituents from Scrophularia ningpoensis root.

METHODS

The compounds were isolated and purified by silica gel and Sephadex LH-20 column chromatography. The structures of these compounds were elucidated on the basis of spectroscopic analysis.

RESULTS

Eleven compounds were isolated and identified as vanillin (1), eugenol (2), isoeugenol methyl ether(3), ferulic acid(4), benzoic acid(5), syringic acid(6) ,rhamnopyranosyl vanilloyl(7), syringic acid-4-O-alpha-L-rhamnopyr-anoside(8), beta-sitosterol(9), adenosine (10) and dibutyl phthalate(11).

CONCLUSION

Compound 1-3 and 6-8 are obtained from this plant for the first time.

Biological screening of Scrophularia nodosa extract and its fractions

Biological screening of Scrophularia nodosa crude extract and its fractions (hexane, chloroform, ethyl-acetate, n-butanol and aqueous) was carried out on phytotoxicity, cytotoxicity, antibacterial, antifungal and analgesic activities. Crude extract and its fractions produced 50-100% phytotoxicity at 1000μ/mL concentration whereas 25-77% phytotoxicity was observed at 10μ/mL concentration. The fractions exhibited significant antibacterial and antifungal effects. The non-toxic results of this plant were recorded in Brine Shrimps Bioassay method at all concentrations. Similarly no significant insecticidal activity was observed in crude extracts and fractions. Analgesic activity results of S. nodosa in mice were found highly significant in crude extract as compared to fractions. In writhing test crude extract at 500 mg/kg showed 65.6% highest inhibitory response in mice.

Biological characteristics of Cionus latefasciatus (Coleoptera: Curculionidae) and effects of temperature on its growth and development

Cionus latefasciatus Voss (Coleoptera: Curculionidae) is one of the most important insect pests on Scrophularia ningpoensis Hemsl. (Scrophulariales: Scrophuhrhceae), which is a well-known traditional Chinese medicine plant in southeast China. The biological characteristics and effects of temperature on the growth and development of C. latefasciatus were studied in nature, in the greenhouse, and in the laboratory. In the area studied, 9-12 generations of this weevil occurred per year depending on climatic conditions. The overwintered adults migrated to the plant-seeding fields in the earlier days of March, and adults of the last generation began to overwinter in early October. Female adults lived for 50-75 d and male adults for 50-65 d at 28 degrees C. Adults fed on leaves, buds, tender stems, and flower stalks during the entire developmental phase of the plant. Female adults began to lay eggs 2-4 d after emergence and laid an average of 330-390 eggs per female at 28 degrees C. The eggs were usually laid on the surface of the leaves or into the leaves. The larvae have four instars judging from the width of the cephalic capsule of the larvae. The larvae fed on leaves and buds of the plant. Under constant temperatures (17, 20, 25, 28, and 30 degrees C) and fixed humidity (75%), the development periods from egg to adult emergence were 36.91, 29.25, 19.11, 17.26, and 15.36 d, respectively, and 346.31 degree-days, in total, above a lower threshold of 7.7 degrees C was required; the survival rates from egg to adult emergence were 49.1, 62.5, 72.0, 78.7, and 50.0%, respectively. Laboratory experiments showed that the optimum temperature for the development from egg to adult emergence was 28 degrees C.

KD-501, a standardized extract of Scrophularia buergeriana has both cognitive-enhancing and antioxidant activities in mice given scopolamine

AIM OF THE STUDY

The cognitive-enhancing and antioxidant activities of KD-501, a standardized extract of the roots of Scrophularia buergeriana Miquel (Scrophulariceae) were investigated.

MATERIALS AND METHODS

KD-501 was orally administered to amnesic mice induced by scopolamine and we performed passive avoidance and the Morris water maze tests. To elucidate the mechanism of cognitive-enhancing activity, the effects of KD-501 on the activities of acetylcholinesterase and antioxidant enzymes within the cortex and hippocampus of mice were evaluated.

RESULTS

Acute and prolonged oral administration of KD-501 significantly ameliorated scopolamine-induced amnesia in passive avoidance test. In the Morris water maze test, acute and prolonged administration of KD-501 improved the impairment of spatial memory induced by scopolamine indicated by the formation of reference and working memories. The activity of acetylcholinesterase was significantly inhibited by KD-501 within the cortex and hippocampus. Moreover, the reduced activities or contents of glutathione reductase, superoxide dismutase (SOD) and reduced GSH within the cortex and hippocampus caused by scopolamine were elevated by the treatment of KD-501.

CONCLUSIONS

Taken together, it could be postulated that KD-501 may exert its potent cognitive-enhancing activity through both anti-acetylcholinesterase and antioxidative actions.

Taxonomical markers in two endemic plants of Sardinia: Verbascum conocarpum and Scrophularia trifoliata

The monoterpenoid composition of Verbascum conocarpum and Scrophularia trifoliata, both endemic plants of Sardinia, was examined. The main chemotaxonomic markers of Scrophulariaceae, the iridoids aucubin, verbascoside and catalpol, were isolated.

Antidepressant effect of three traditional Chinese medicines in the learned helplessness model

Plantago asiatica, Scrophularia ningpoensis and Ilex pubescens are among the traditional Chinese medicines which are more frequently prescribed for treating depression-like ailments in the past and present traditional Chinese medical practice. The present work was therefore conducted to evaluate the presumable antidepressant effects of the extracts derived from the three remedies in mice using the learned helplessness model being used for screening for antidepressant compounds in modern medicinal researches. As a result, the petroleum extracts of Plantago asiatica and Ilex pubescens as well as the EtOAc extract of Scrophularia ningpoensis and the petroleum-soluble fraction of the acidic hydrolysate of the water extract of Ilex pubescens (after petroleum extraction) decreased significantly the number of escape failures relative to the control. The finding rationalized the clinical prescription of the herbs for the treatment of depression, and shined a clue for the characterization of the antidepressant phytochemical(s).

Iridoids fromScrophularia buergeriana attenuate glutamate-induced neurotoxicity in rat cortical cultures

In previous work, we isolated 7 neuroprotective iridoid glycosides from the 90% MeOH fraction of Scrophularia buergeriana (Scrophulariaceae). We therefore investigated the mode of action of 8-O-E-p-methoxycinnamoyl-harpagide (8-MCA-Harp), the most potent neuroprotective iridoid, and its aglycone, harpagide (Harp) using primary cultures of rat cortical cells in vitro. 8-MCA-Harp only revealed its neuroprotective activity in a pretreatment paradigm; this iridoid had more selectivity in protecting neurons against N-methyl-D-aspartate (NMDA)-induced neurotoxicity as opposed to that induced by kainic acid (KA). On the other hand, Harp exerted significant neuroprotective activity when it was administered either before or after glutamate insult and protected cultured neuronal cells from neurotoxicity induced by NMDA or KA. Furthermore, Harp significantly prevented the decrease of glutathione, an antioxidative compound in the brain, in our cultures. Finally, 8-MCA-Harp and Harp could successfully reduce the overproduction of nitric oxide and the level of cellular peroxide in cultured neurons. Collectively, these results suggested that Harp and 8-MCA-Harp protected primary cultured neurons against glutamate-induced oxidative stress primarily by acting on the antioxidative defense system and on glutamatergic receptors, respectively.

Anti-amnestic activity of E-p-methoxycinnamic acid from Scrophularia buergeriana

We previously reported that phenylpropanoids isolated from the roots of Scrophularia buergeriana Miquel (Scrophulariaceae) protected cultured cortical neurons against glutamate-induced neurotoxicity [Kim and Kim, Phytochemistry, 54 (2000) 503-509; Kim et al., Br. J. Pharmacol. 135 (2002) 1281-1291]. In the present study, we examined the anti-amnestic activities of phenylpropanoids in mice with amnesia induced in vivo by scopolamine. Among the phenylpropanoids tested through passive avoidance tasks, buergeriside A1, buergeriside C1, E-p-methoxycinnamic acid (E-p-MCA) and E-isoferulic acid significantly improved the deficit of memory induced by scopolamine. This suggested that the alpha,beta-unsaturated carboxyl moiety and the para-methoxy group in phenylpropanoids (E-p-MCA) might be a crucial component in their cognition-enhancing activity. Indeed, E-p-MCA (0.01-2 mg/kg body weight, i.p.), given in pre- or post-treatment paradigms, significantly ameliorated scopolamine-induced amnesia as determined by passive avoidance tasks and prevented or aided in the recovery of memory to a level that was about 60% of control. In addition, E-p-MCA (0.1-1.0 mg/kg body weight, i.p.) significantly improved impairments of spatial learning and memory induced by scopolamine; the compound reduced deficits in both long- and short-term memories as measured by the Morris water maze test. We suggest, therefore, that E-p-MCA may ultimately hold significant therapeutic value in alleviating certain memory impairments observed in dementia.

Scropolioside-D2 and harpagoside-B: two new iridoid glycosides from Scrophularia deserti and their antidiabetic and antiinflammatory activity

Five iridoid glycosides, including the two new compounds scropolioside-D(2) (1) and harpagoside-B (2), were isolated from the aerial parts of Scrophularia deserti DEL (Scrophulariaceae). Their structures were elucidated on the basis of spectral data to be 6-O-[2",4"-di-O-acetyl-3"-O-trans-cinnamoyl)-alpha-L-rhamnopyranosyl]-8 alpha-hydroxymethyl-1 alpha,5 beta,6 alpha,7 alpha,9 beta-pentahydro-7(8)-epoxy-2-oxaind-3-ene-1-O-beta-D-glucopyranoside-6'-O-acetate (1) and 5-O-beta-hydroxy-8-O-beta-trans-cinnamoyl-8 alpha-methyl-1,6,7,9-tetrahydro-2-oxaind-3-ene-1-O-beta-D-glucopyranoside (2), respectively. In addition, three more iridoid glycosides, scropolioside-D (3), koelzioside (4), and 8-O-acetyl-harpagide (5), were also isolated and characterized from this source. The biological activity and the structure activity relationship of the compounds were also studied, and scropolioside-D (3) and harpagoside-B (2) were found to possess significant antidiabetic and antiinflammatory activity, respectively.