Antibacterial compounds from the leaves of Acanthopanax senticosus

Chiisanogenin (1), hyperin (2) and chiisanoside (3) were isolated from the leaves of Acanthopanax senticosus, and were tested for their inhibitory activities against 6 strains of bacteria. Among them, chiisanogenin (1) revealed broad but moderate antibacterial activities against G (+) and G (-) bacteria, the minimum inhibitory concentration (MIC) being in the range of 50-100 microg/ml.

In vivo anti-oxidant activities of tectochrysin

The anti-oxidant activities of tectochrysin, a major compound of propolis, were investigated. Tectochrysin exhibited a significant decrease in serum transaminase activities elevated by hepatic damage induced by CCl4-intoxication in rats. Tectochrysin tested exhibited a lipid peroxidation causing a significant decrease in MDA production in TBA-reactant assay. Tectochrysin was strong in the increase in the anti-oxidant enzymes such as hepatic cytosolic superoxide dismutase, catalase and glutathione peroxidase activities in CCl4-intoxicated rats. These results suggest that tectochrysin possess not only the anti-oxidant, but also the activities in CCl4-intoxicated rats. Especially, tectochrysin was found to cause significant increases in the rat liver cytosolic SOD, catalase, GSH-px activities as well as a significant decrease in the MDA production.

Pharmacological activities of a new glycosaminoglycan, acharan sulfate isolated from the giant African snail Achatina fulica

Acharan sulfate (AS) is a glycosaminoglycan (GAG) prepared from the giant African snail, Achatina fulica. In this study, some biological activities of AS were evaluated on the basis of structural similarities to heparin/heparan sulfate and the biological functions of GAGs. We demonstrated that it exhibited strong immunostimulating activities as measured by carbon clearance test in mice and in vivo phagocytosis. It also exhibited a significant hypoglycemic activity in epinephrine (EP)-induced hyperglycemia as well as antifatigue effects by weight-loaded forced swimming test. And it showed hypolipidemic activities in cholesterol-rich mixture induced hyperlipidemia in rats. The above results indicate that AS has diverse biological activities and suggest therapeutically important target molecules.

Inhibition of prostaglandin E(2) production by taiwanin C isolated from the root of Acanthopanax chiisanensis and the mechanism of action

Five lignans, l-sesamin, savinin, helioxanthin, taiwanin C, and cis-dibenzylbutyrolactone, were isolated from the root of Acanthopanax chiisanensis (Araliaceae), a Korean medicinal plant, and their inhibitory effects on the production of prostaglandin (PG) E(2) stimulated by 12-O-tetradecanoylphorbol 13-acetate (TPA) in rat peritoneal macrophages were examined. Among the five lignans, taiwanin C was the most potent (IC(50)=0.12 microM), followed by helioxanthin, cis-dibenzylbutyrolactone, and savinin. l-Sesamin had no effect. Taiwanin C showed no inhibitory effect on the TPA-induced release of radioactivity from [3H]arachidonic acid-labeled macrophages, nor did it inhibit the expression of cyclooxygenase (COX)-2 protein induced by TPA. However, the activities of isolated COX-1 and COX-2 were inhibited by taiwanin C (IC(50)=1.06 and 9.31 microM, respectively), reflecting the inhibition of both COX-1- and COX-2-dependent PGE(2) production in the cell culture system. These findings suggest that the mechanism of action of taiwanin C in the inhibition of PGE(2) production is the direct inhibition of COX enzymatic activity.

Sessiline, a new nitrogenous compound from the fruits of Acanthopanax sessiliflorus

A new nitrogenous compound, named sessiline [5-(5-oxo-pyrrolidin-2-yloxymethyl)-furan-2-carbaldehyde (1)], was isolated from the fruits of Acanthopanax sessiliflorus, together with (-)-sesamin, scoparone, protocatechuic acid, ursolic acid, hyperin and 5-hydroxymethylfurfural by CC. The structures of these compounds were elucidated by physico-chemical and spectral analysis.

Inhibition by acharan sulphate of angiogenesis in experimental inflammation models

1. The effects of acharan sulphate, a glycosaminoglycan isolated from the giant African snail Achatina fulica, on angiogenesis in the granulation tissue were analysed using an air pouch-type carrageenin-induced inflammation model in rats and a cotton thread-induced inflammation model in mice. 2. In the carrageenin-induced inflammation model in rats, intra-pouch injections of acharan sulphate (5 and 50 micro g) inhibited the pouch fluid accumulation and the granulation tissue formation as well as the angiogenesis in the granulation tissue at day 6 in a dose-dependent manner. 3. The inhibitory effects of acharan sulphate at 50 micro g on the pouch fluid accumulation and the leucocyte infiltration into the pouch fluid was not so effective as that of the cyclo-oxygenase inhibitor indomethacin at 100 micro g, but the inhibitory effects of acharan sulphate at 50 micro g on the granulation tissue formation and angiogenesis in the granulation tissue were almost the same as those of indomethacin at 100 micro g. 4. Acharan sulphate did not affect levels of vascular endothelial growth factor (VEGF) in the granulation tissue and in the pouch fluid at day 6, but indomethacin significantly lowered them. 5. In the cotton thread-induced inflammation model in mice, injections of acharan sulphate (10 micro g) at the site of the cotton thread implantation inhibited the granulation tissue formation and angiogenesis as indomethacin (20 micro g) did. Acharan sulphate (10 micro g) did not affect levels of VEGF in the cotton thread-induced granulation tissue at day 5, but indomethacin (20 micro g) significantly lowered them. 6. In culture of human vascular endothelial cells, acharan sulphate at 10 and 100 micro g ml(-1) inhibited VEGF-induced capillary tube formation. 7. These findings suggest that the inhibitory effect of acharan sulphate on angiogenesis in carrageenin- and cotton thread-induced granulation tissues is not due to the inhibition of VEGF protein induction, but is due to the inhibition of VEGF-induced vascular tube formation.

Isoflavonoids from the rhizomes of Belamcanda chinensis and their effects on aldose reductase and sorbitol accumulation in streptozotocin induced diabetic rat tissues

Aldose reductase, the key enzyme of the polyol pathway, is known to play important roles in the diabetic complication. The inhibitors of aldose reductase, therefore, would be potential agents for the prevention of diabetic complications. To evaluate active principles for the inhibition of aldose reductase from the rhizomes of Belamcanda chinensis, twelve phenolic compounds were isolated and tested for their effects on rat lens aldose reductase. As a result, isoflavones such as tectorigenin, irigenin and their glucosides were found to show a strong aldose reductase inhibition. Tectoridin and tectorigenin, exhibited the highest aldose reductase inhibitory potency, their IC50 values, being 1.08 x 10(-6) M and 1.12 x 10(-6) M, respectively, for DL-glyceraldehyde as a substrate. Both compounds, when administered orally at 100 mg/kg for 10 consecutive days to streptozotocin-induced diabetic rats, caused a significant inhibition of sorbitol accumulation in the tissues such as lens, sciatic nerves and red blood cells. Tectorigenin showed a stronger inhibitory activity than tectoridin. From these results, it is suggested that tectorigenin is attributed to be a promising compound for the prevention and/or treatment of diabetic complications.

Crystal structure of byakangelicin (C17H18O7)

The crystal structure of byakangelicin, one of furanocoumarin aldose reductase inhibitors, was determined by X-ray diffraction method. The crystal is triclinic, with a = 8.114(1), b = 10.194(1), c = 11.428(1)A, a = 111.50(1), beta= 95.57(1), gamma = 112.52(1) degrees , Dx = 1.41, Dm = 1.39 g/cm3, space group P1 and Z = 2. The intensity data were collected by omega-2theta scan method with CuK(a) radiations. The structure was solved by direct method and refined by full matrix least-squares procedure to the final R-value of 0.056. There are two molecules with different conformations in an asymmetric unit. The molecules are kept by two intermolecular O-HO type hydrogen bonds and van der Waal's forces in the crystal. The absolute configuration of the molecules was estimated to S-form by the 'Eta refinement' procedure.

Phytochemical constituents from the fruits of Acanthopanax sessiliflorus

Six compounds were isolated from the fruits of Acanthopanax sessiliflorus. Their structures were elucidated as (-)-sesamin, scoparone, protocatechuic acid, ursolic acid, hyperin and 5-hydroxymethylfurfural by physicochemical and spectroscopic analysis. Among them, scoparone, ursolic acid and 5-hydroxymethylfurfural were isolated for the first time from Acanthopanax species.

Effect of the essential oil from the flowers of Magnolia sieboldii on the lipopolysaccharide-induced production of nitric oxide and prostaglandin E2 by rat peritoneal macrophages

The essential oil from the flowers of Magnolia sieboldii was tested for its effects on lipopolysaccharide (LPS)-induced production of nitric oxide (NO) and prostaglandin E(2) (PGE(2)) by rat peritoneal macrophages. It was shown to induce the production of NO and PGE 2 in a concentration-dependent manner (3 - 30 microg/ml). Gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) led to the identification of sixty compounds, of which beta-elemene (18.0 %), alpha-terpinene (14.83 %) and beta-myrcene (12.72 %) were the major constituents. Among these three compounds, alpha-terpinene was found to be the most effective one with inhibitory activity on NO and PGE(2) production by LPS-stimulated rat peritoneal macrophages.

Effects of naturally occurring isoflavones on prostaglandin E2 production

Previously, we reported that the isoflavones tectorigenin and tectoridin, a glycosylated tectorigenin, isolated from the rhizomes of Belamcanda chinensis have an activity to inhibit prostaglandin (PG) E2 production in 12-O-tetradecanoylphorbol 13-acetate (TPA)-stimulated rat peritoneal macrophages. The inhibitory effect of tectorigenin is more potent than that of tectoridin. In this study, we investigated the structure-activity relationship of various isoflavones in the inhibition of PGE2 production in TPA-stimulated rat peritoneal macrophages. The isoflavones examined were isolated from the rhizomes of B. chinensis, and the flowers and the rhizomes of Pueraria thunbergiana. The order of potency to inhibit PGE2 production was as follows; irisolidone, tectorigenin > genistein > tectoridin (tectorigenin 7-glucoside), glycitein > daidzein. Kakkalide (irisolidone 7-xylosylglucoside), glycitin (glycitein 7-glucoside), daidzin (daidzein 7-glucoside), puerarin (daizein 8-glucoside), and genistin (genistein 7-glucoside) showed no significant inhibition. These findings indicated that 6-methoxylation and 5-hydroxylation increase the potency to inhibit PGE2 production and 7-O-glycosylation decreases the inhibitory activity.

PTEN gene mutations in colorectal cancers displaying microsatellite instability

To determine the relationship between the mutation of the PTEN gene and genomic instability in human colorectal cancer, we screened the PTEN gene in 32 colorectal cancers (eight cell lines and 24 tissues) displaying microsatellite instability (MSI) and 32 colorectal cancers (six cell lines and 26 tissues) displaying microsatellite stability (MSS). Of 64 samples, six frameshift mutations were identified in six MSI colorectal cancers (two cell lines and four tumor tissues) but not in MSS colorectal cancers. Of the six MSI colorectal cancers containing PTEN mutation, two case (one cell line and one tumor tissue) showed biallelic mutation of PTEN. Furthermore, to compare the frequency of PTEN mutation with that of other MSI target genes, the mononucleotide repeat sequences of TGF-betaRII, BAX, IGFIIR, hMSH6 and hMSH3 were analyzed. The frequencies of frameshift mutation were revealed 78% in TGF-betaRII, 56% in BAX, 46.9% in hMSH3, 37.5% in hMSH6, 21.9% in IGFIIR, and 18.8% in PTEN. These results suggest that the PTEN gene is a target of genomic instability in MSI colorectal tumorigenesis.

Inhibition of prostalglandin E2 production by 2'-hydoxychalcone derivatives and the mechanism of action

The effects of 14 synthetic 2'-hydroxychalcone derivatives on prostaglandin E2 (PGE2) production in rat peritoneal macrophages stimulated by the protein kinase C activator, 12-O-tetradecanoylphorbol 13-acetate (TPA), were examined to clarify the structure-activity relationship. 2',4-Dihydroxy-4'-methoxychalcone (compound 3), 2',4-dihydroxy-6'-methoxychalcone (compound 8) and 2'-hydroxy-4'-methoxychalcone (compound 9) suppressed PGE2 production more potently than the other compounds. The IC50 (50% Inhibitory concentration) value for compounds 3, 8 and 9 was calculated to be 3 microM. The activity of cyclooxygenase (COX)-1 was inhibited slightly by compound 9, but that of COX-2 was not inhibited. At concentrations that inhibited the production of PGE2, compound 9 had no effect on the release of radioactivity from [3H]arachidonic acid-labelled macrophages stimulated by TPA. Western-blot analysis revealed that the induction of COX-2 protein by TPA was inhibited by compound 9 in parallel with the inhibition of PGE2 production. Compounds 3 and 8 had similar effects. These findings suggest that 4'-methoxyl and 6'-methoxyl groups are required for the expression of more potent inhibitory activity against PGE2 production, and that the inhibition of PGE2 production by these 2'-hydroxychalcone derivatives is due to the inhibition of TPA-induced COX-2 protein expression.

Ecotoxicity monitoring of hydrocarbon-contaminated soil using earthworm (Eisenia foetida)

In order to assess the applicability of an earthworm bioassay as a technique for monitoring the soil flushing process, short-term and long-term toxicity tests were conducted on remediated soil using various pore volumes of surfactant solution. Results obtained on short-term toxicity testing indicated that biomass increased as the soil flushing proceeded, and on diesel-contaminated soils this testing showed that the effect of diesel is lethal and that 25 pore volumes of soil surfactant were not sufficient to abrogate the toxic effect of diesel. These short-term tests also showed strong sublethal relationships between the development of biomass, and the concentrations of toxic chemicals in the soil. Although relationships between contaminants and the various bioassay parameters examined were not significant in long-term testing, an increase in the number of juveniles was observed over time, which may have been a consequence of a reduction in toxicity associated with the flushing process.

Nicotine-induced behavioral sensitization is associated with extracellular dopamine release and expression of c-Fos in the striatum and nucleus accumbens of the rat

It is well known that repeated injections of nicotine produce progressively larger increases in locomotor activity, an effect referred to as behavioral sensitization. This study was carried out to investigate the neural mechanisms underlying nicotine-induced behavioral sensitization using in vivo microdialysis and Fos-like immunohistochemistry (FLI). Rats were given repeated injections of saline or nicotine (0.4 mg/kg s.c., twice daily for 7 days) followed by one challenge injection on the 4th day after the last daily injection. Systemic challenge with nicotine produced a much larger increase in locomotor activity in nicotine-pretreated rats (659.1+/-94.9 counts/2 h) than in saline-pretreated rats (218.1+/-61 counts/2 h). A direct local challenge of nicotine (1 or 5 mM) via a microdialysis probe in the nucleus accumbens or striatum induced a much greater dose-dependent increase of dopamine (DA) output in nicotine-pretreated rats than in saline-pretreated rats. Furthermore, in parallel with the behavioral and biochemical data, systemic challenge with nicotine produced marked Fos-like immunohistochemistry in the nucleus accumbens and the striatum in the nicotine-pretreated rats. Taken together, this study demonstrates that behavioral sensitization is clearly associated with an increase in DA release and activation of Fos-like immunoreactive cells in the striatum and the nucleus accumbens produced by repeated nicotine treatment. Our results strongly suggest that the striatum and the nucleus accumbens may play a major role in nicotine-induced behavioral sensitization. The present results are discussed in terms of the development and expression of nicotine-induced behavioral sensitization.

Inhibition of prostaglandin E2 production by platycodin D isolated from the root of Platycodon grandiflorum

Platycodin D, isolated from the root of Platycodon grandiflorum A. DC. (Campanulaceae) suppressed prostaglandin E2 production at 10 and 30 microM in rat peritoneal macrophages stimulated by the protein kinase C activator 12-O-tetradecanoylphorbol 13-acetate (TPA). Platycodin D3 and oleanolic acid showed no effect at these concentrations. Western blot analysis revealed that the induction of COX-2 protein by TPA was inhibited by platycodin D in parallel with the inhibition of prostaglandin E2 production. Platycodin D showed no direct effect on COX-1 and COX-2 activities. TPA-induced release of [3H]arachidonic acid from pre-labeled macrophages was also not inhibited by platycodin D.

Microsatellite instability in double primary cancers of the colorectum and stomach

Little is known about genetic alterations of patients who present multiple primary cancers. We hypothesized that microsatellite instability (MSI) is one of the underlying genetic factors in the development of double primary cancers in colorectal cancer patients. We examined for MSI in 41 colorectal cancer patients who presented with extra-colonic primary cancers consisted of 17 gastric and 24 non-gastric cancers. Coincident MSI+ in tumors of two organs were observed in 3 (17.7%) of 17 patients with colon and stomach cancers and 0 of 24 patients with colon and non-gastric cancers (P =.03). In 17 patients with colon and stomach cancers, 6 (31.6%) of 19 colon cancers and 3 (17.7%) of 17 gastric cancers exhibited MSI+. Among four patients with metachronous colon cancers who were identified within the 41 double primary cancer patients, two patients were associated with the MSI+ phenotype. In summary, the prevalent coincidence of MSI suggests that genetic defect of mismatch repair deficiency may be responsible for a small subset of double primary cancers of the colorectum and stomach.

Impacts of elevated level of hCG in serum on clinical course and radiotherapy results in the histology-confirmed intracranial germinomas

The prognosis of intracranial germinoma producing the human chorionic gonadotropin (hCG) is controversial due to limited information. We undertook a retrospective analysis to determine whether this type of tumor has similar clinical course and prognosis to hCG non-secreting germinoma. Thirty-one histologically confirmed intracranial germinoma patients who had pretreatment hCG examination in serum/CSF were treated with radiotherapy between 1980 and 1996. hCG level was measured by immunoradioassay of beta subunit of hCG. Six patients had elevated serum hCG levels and were defined as having hCG secreting germinoma. All except three patients received craniospinal axis irradiation. The follow-up ranged from 19-175 months with a median of 63 months. hCG secreting germinoma accounted for 19% of intracranial germinoma cases. Elevated hCG levels ranged from 39-260 IU/l in serum. No difference was found between hCG non-secreting germinoma and hCG secreting germinoma in terms of patient or treatment characteristics. There was no recurrence among the six hCG secreting germinoma patients. The 5-year overall and disease-free survival rates were 96% for patients with hCG non-secreting germinomas and 100% for the patients with hCG secreting germinomas. The survival difference was not significant (p = 0.59). Our results suggest that elevated level of hCG did not result in any differences in the clinical characteristics or survival after radical radiotherapy in histologically confirmed intracranial germinoma.

Mutations in fibroblast growth factor receptor 2 and fibroblast growth factor receptor 3 genes associated with human gastric and colorectal cancers

Autosomal dominant disorders of skeletal and cranial development have been linked to fibroblast growth factor receptor (FGFR) 2 and FGFR3. Here we report two identical mutations in FGFR2 that cause craniosynostosis syndromes, Crouzon, Apert, and Pfeiffer in gastric carcinoma. A missense mutation (Ser267Pro) in exon IIIa and a splice site mutation (940-2A-->G) in exon IIIc were detected in gastric cancer patients. Interestingly, these heterozygous somatic mutations are identical to the germinal activating mutations in FGFR2 reported previously in craniosynostosis syndromes. In addition, the two novel mutations of FGFR3 in colorectal carcinomas were identified. All identified mutations occurred at highly conserved sequences, not only in the FGFR family of molecules, but also throughout evolution and clustered in the immunoglobulin-like loop-III domain, highlighting the functional importance of this domain. Our results indicate that FGFR2 and FGFR3, in addition to their potential role in skeletal dysplasias, play an important role in tumorigenesis.

Expression of the cAMP response element binding protein (CREB) in hippocampus produces an antidepressant effect

BACKGROUND

Recent studies have demonstrated that chronic antidepressant treatment increases the expression of the cyclic amp (cAMP) response element binding protein (CREB) in rat hippocampus. The study presented here was conducted to determine if CREB is a relevant target that produces an antidepressant-like effect.

METHODS

We employed the herpes simplex virus (HSV)-mediated gene transfer technique to overexpress CREB and determined its effect on the learned helplessness and forced swim tests, two established models used for pharmacological screening of antidepressant drugs.

RESULTS

In the learned helplessness model, rats that received bilateral microinjection of HSV-CREB into the dentate gyrus showed significantly fewer escape failures in the subsequent conditioned avoidance test than those injected with control vector (HSV-LacZ). In contrast, microinjection of HSV-CREB in either the CA1 pyramidal cell layer of hippocampus or the prefrontal cortex did not produce an antidepressant response. In the forced swim test, CREB expression in the dentate gyrus resulted in a significantly shorter immobility time than those injected with HSV-LacZ.

CONCLUSIONS

These results demonstrate that over-expression of CREB in hippocampus results in an antidepressant effect and suggest that CREB may serve as a potential molecular target for novel therapeutic agents.

Oncogenic osteomalacia associated with mesenchymal tumour detected by indium-111 octreotide scintigraphy

In a 40-year-old man who had suffered from vague and generalized bone pains for 7 years due to oncogenic osteomalacia, the causative tumour was finally detected by Indium-111 octreotide scintigraphy. Some characteristics of the tumour associated with oncogenic osteomalacia, such as its size, growth rate, location and origin, often make the diagnosis difficult. However, the recent discovery of somatostatin receptors in mesenchymal tumours, which are the most common cause of oncogenic osteomalacia, has raised the possibility of early detection of this devastating disorder. Here, we report that radiolabelled octreotide scintigraphy has a potential role as a diagnostic tool in oncogenic osteomalacia. However, the exact role of somatostatin receptors in tumours associated with oncogenic osteomalacia still remains elusive.

Antioxidant and immunostimulating activities of the fruiting bodies of Paecilomyces japonica, a new type of Cordyceps sp

Cordyceps is negative for its many biological activities and a tonic for restoring vital functions in traditional Chinese medicine. In an effort to evaluate the pharmacological effects, including the antiaging effect of the fruiting bodies of the cultivated Paecilomyces japonica fungus, a new type of Cordyceps sp. was investigated. This investigation was focused on ultimately revealing its biologically active principles, its effects on free-radical scavenging enzymes, lipid peroxidation, as well as its immunological functions. As a result, both water and methanol extracts were found to cause not only significant increases in rat liver cytosolic SOD, catalase, and GSEH-px activities, but also a significant decrease in MDA production in TBA reactant assay in rats. The extracts also showed immunostimulating activity as measured by carbon clearance, weight-loaded forced swimming performances, and immobilizing stress in mice. Using bioassay-guided systematic fractionation of the extracts, two pure compounds were isolated as active principles from low molecular-weight fraction, a protein-bound polysaccharide was isolated that showed a marked increase in the liver enzyme activities, as well as a significant inhibition of lipid peroxidation.

ECS-Induced mossy fiber sprouting and BDNF expression are attenuated by ketamine pretreatment

Recent evidence suggests hippocampal and possibly cortical atrophy is associated with major depression. Chronic electroconvulsive seizures (ECS) induce brain-derived neurotrophic factor (BDNF) expression and sprouting of the mossy fiber pathway in the hippocampus, effects that may be related to electroconvulsive therapy's (ECT) mechanism of action. The objective of this study was to investigate the role of NMDA (N-methyl-D-aspartate) receptor in mediating the ECS-induced mossy fiber sprouting and BDNF expression. Timm histochemistry and in situ hybridization methodologies were used to determine the effect of pretreatment with ketamine, an NMDA antagonist, on ECS-induced sprouting and BDNF expression. The results demonstrate the ability of ketamine pretreatment to attenuate ECS-induced sprouting in the dentate gyrus and BDNF expression in the medial prefrontal cortex and the dentate gyrus. In addition, we found a significant decrease in seizure duration with ketamine pretreatment. These data suggest that NMDA receptor activation contributes to both the regulation of neurotrophic factor expression and the morphological changes associated with seizure activity. However, other effects resulting from shortened seizure duration and seizure intensity cannot be excluded. These findings are of increasing interest, as they relate to the use of ECT in the treatment of depression, and the specific anesthetic agents that are used.

An anti-inflammatory principle from cactus

In previous studies, the ethanol extract of cactus (Opuntia ficus-indica) showed potent anti-inflammatory action. In the present study, following fractionation of the methanol extract of cactus stems guided by adjuvant-induced chronic inflammation model in mice, an active anti-inflammatory principle has been isolated and identified as beta-sitosterol.