Anti-Neurodegenerative Biflavonoid Glycosides from Impatiens balsamina

Four biflavonoid glycosides, balsamisides A-D (1-4), and nine known compounds (5-13) were obtained from the white petals of Impatiens balsamina. The 2D structures of the purified phytochemicals were established using conventional NMR techniques in addition to the new long-range HSQMBC NMR experiment. Acid hydrolysis followed by experimental and quantum-mechanics-based ECD data analysis permitted full configurational assignment of the purified metabolites. Compounds 1-13 were assessed for their potential to impede the generation of nitric oxide in lipopolysaccharide-stimulated BV2 cells. They were also investigated for potential neuroprotective activity using C6 cells and cytotoxicity against some human tumor cell lines, but were inactive (IC₅₀ > 10 μM) against all the cell lines.

P2X1 Receptor-Mediated Ca2+ Influx Triggered by DA-9801 Potentiates Nerve Growth Factor-Induced Neurite Outgrowth

Nerve growth factor (NGF)-induced neuronal regeneration has emerged as a strategy to treat neuronal degeneration-associated disorders. However, direct NGF administration is limited by the occurrence of adverse effects at high doses of NGF. Therefore, development of a therapeutic strategy to promote the NGF trophic effect is required. In view of the lack of understanding of the mechanism for potentiating the NGF effect, this study investigated molecular targets of DA-9801, a well-standardized Dioscorea rhizome extract, which has a promoting effect on NGF. An increase in intracellular calcium ion level was induced by DA-9801, and chelation of extracellular calcium ions with ethylene-bis(oxyethylenenitrilo)tetraacetic acid (EGTA) suppressed the potentiating effect of DA-9801 on NGF-induced neurite outgrowth. In addition, EGTA treatment reduced the DA-9801-induced phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/2), the major mediators of neurite outgrowth. To find which calcium ion-permeable channel contributes to the calcium ion influx induced by DA-9801, we treated PC12 cells with various inhibitors of calcium ion-permeable channels. NF449, a P2X1 receptor selective antagonist, significantly abolished the potentiating effect of DA-9801 on NGF-induced neurite outgrowth and abrogated the DA-9801-induced ERK1/2 phosphorylation. In addition, transfection with siRNA of P2X1 receptor significantly reduced the DA-9801-enhanced neurite outgrowth. In conclusion, calcium ion influx through P2X1 receptor mediated the promoting effect of DA-9801 on NGF-induced neurite outgrowth via ERK1/2 phosphorylation.

Development of ciclopirox nail lacquer with enhanced permeation and retention

Onychomycosis is a prevailing disease caused by fungal infection of nails that mostly affects athletes and the elderly. Ciclopirox is approved by the US Food and Drug Administration for the topical treatment of onychomycosis. However, the desired penetration of ciclopirox into the nail bed has not been achieved via topical application for efficient treatment. Therefore, the main aim of this study was to enhance ciclopirox permeation and retention in nail by the development of a new nail lacquer formulation. We screened the effects of different solvents, alkalizing agents, and permeation enhancers on the permeation of bovine hooves by ciclopirox and its retention in human nail clippings. The results suggest that isopropyl alcohol, potassium hydroxide, and urea as the solvent, alkalizing agent, and permeation enhancer, respectively, improved the permeation of the ciclopirox nail lacquer formulation the most with high flux rates. Comparison of the final formulation and marketed product revealed enhanced retention of ciclopirox from our developed formulation in human nail clippings. Therefore, our newly developed nail lacquer may be a potentially effective formulation for the treatment of onychomycosis in humans.

Phenolic derivatives from the rhizomes of Dioscorea nipponica and their anti-neuroinflammatory and neuroprotective activities

ETHNOPHARMACOLOGICAL RELEVANCE

Dioscorea nipponica (Dioscoreaceae) have been used as traditional medicines for diabetes, inflammatory and neurodegenerative diseases in Korea. The aim of the study was to isolate the bioactive components from the rhizomes of Dioscorea nipponica and to evaluate their anti-neuroinfalmmatory and neuroprotective activities.

MATERIAL AND METHODS

The phytochemical investigation of 50% EtOH extract of Dioscorea nipponica using successive column chromatography over silica gel, Sephadex LH-20, and preparative high performance liquid chromatography (HPLC) resulted in the isolation and identification of 17 phenolic derivatives, including four new phenolic compounds (1-4). The structural elucidation of these compounds was based on spectroscopic methods, including 1D and 2D nuclear magnetic resonance (NMR) spectroscopy techniques, mass spectrometry, and optical rotation. All isolated compounds were evaluated for their effects on nerve growth factor (NGF) secretion in a C6 rat glioma cell line and nitric oxide (NO) production in lipopolysaccharide (LPS)-activated BV2 cells. The neurite outgrowth of compound 16 was further evaluated by using mouse neuroblastoma N2a cell lines.

RESULTS

Three new stilbene derivatives, diosniponol C (1), D (2) and diosniposide A (3) and one new phenanthrene glycoside, diosniposide B (4), together with 13 known compounds were isolated from the rhizomes of Dioscorea nipponica. Of the tested compounds (1-17), phenanthrene, 3,7-dihydroxy-2,4,6-trimethoxy-phenanthrene (16) was the most potent NGF inducer, with 162.35±16.18% stimulation, and strongly reduced NO levels with an IC50 value of 19.56 μM in BV2 microglial cells. Also, it significantly increased neurite outgrowth in N2a cells.

CONCLUSIONS

This study supports the ethnopharmacological use of Dioscorea nipponica rhizomes as traditional medicine.

Identification of antitumor lignans from the seeds of morning glory (Pharbitis nil)

In the search for antitumor compounds from Korean natural resources, activity-guided fractionation and purification processes were used on seeds of morning glory (Pharbitis nil). Air-dried P. nil seeds were extracted with ethanol and separated into n-hexane, chloroform, ethyl acetate, and n-butanol. Four new lignans, pharbilignans A-D (1-4) were isolated from the most active ethyl acetate fraction of the ethanol extract. Their structures were characterized on the basis of spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance (NMR) techniques, high resolution mass spectrometry (HRMS), and circular dichroism (CD) spectroscopy. The cytotoxic activities of the isolates (1-4) were evaluated by determining their inhibitory effects on four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15) using a sulforhodamine B (SRB) bioassay. Pharbilignan C (3) showed potent cytotoxicity against A549, SK-OV-3, SK-MEL-2, and HCT-15 cell lines with IC50 values of 1.42, 0.16, 0.20, and 0.14 μM, respectively. On the basis of the expanded understanding that inflammation is a crucial cause in tumor progress, we also evaluated anti-inflammatory activity of the isolates (1-4). Pharbilignan C (3) strongly inhibited nitric oxide (NO) production in the lipopolysaccharide (LPS)-activated BV-2 microglia cell line with an IC50 value of 12.8 μM.

Bioactive sesquiterpenes from the essential oil of Thuja orientalis

A phytochemical investigation on the essential oil of Thuja orientalis resulted in the isolation and identification of three new sesquiterpenes, 3α-methoxy-4α-epoxythujopsane (1), Δ³,¹⁵-4β-epoxythujopsene (2), and Δ³,⁴-thujopsen-2,15-diol (3), together with eight known sesquiterpenoids (4-11). The structures of these new compounds were elucidated based on spectroscopic data analyses including extensive 2D-NMR data and HR-ESIMS. The full assignments of ¹H and ¹³C NMR chemical shifts for thujopsadiene (4) were obtained by 2D-NMR for the first time. All compounds (1-11) showed antiproliferative activities against the SK-OV-3 and SK-MEL-2 cell lines with IC₅₀ values of 5.85-28.64 µM. In addition, compounds 1, 3, 4, 7, 8, and 9 significantly inhibited nitric oxide production in lipopolysaccharide-activated BV-2 cells with IC₅₀ values of 3.93-17.85 µM without cell toxicity.

Pharbinilic acid, an allogibberic acid from morning glory (Pharbitis nil)

Pharbinilic acid (1), the first naturally occurring allogibberic acid, was isolated from ethanol extracts of morning glory (Pharbitis nil) seeds. Its absolute configuration was determined by NOESY NMR and ECD experiments. Compound 1 showed weak cytotoxicity against A549, SK-OV-3, SK-MEL-2, and HCT-15 cells and weakly inhibited nitric oxide production in lipopolysaccharide-activated BV-2 microglia cells.

Anti-neuroinflammatory diarylheptanoids from the rhizomes of Dioscorea nipponica

In a continuing search for bioactive constituents from Dioscoreaceae medicinal plants, two new cyclic diarylheptanoids, diosniponol A (1) and B (2), together with 10 known compounds (3-12) were isolated from the rhizomes of Dioscorea nipponica. The structures of these new compounds were determined by spectroscopic analyses, including extensive two-dimensional nuclear magnetic resonance, high-resolution mass spectrometry, and optical rotation. All isolated compounds 1-12 were evaluated for their effects on nitric oxide (NO) production in murine microglia cell line BV-2. Compounds 8 and 11 showed potent inhibitory activities on NO production (IC50 13.36 and 14.36 μM, respectively) without cell toxicity in lipopolysaccharide-activated BV-2 cells.

Withanolides from the rhizomes of Dioscorea japonica and their cytotoxicity

Edible yams are tropical crops that serve as important staple foods in many parts of the world. The rhizome of Dioscorea japonica , well-known as "Japanese yam", is a food and medicinal source known as "San Yak" in Korea. Bioassay-guided fractionation and chemical investigation of the extract of this yam resulted in the identification of two new withanolides, named dioscorolide A (1) and dioscorolide B (2). The structures of these new compounds were determined by spectroscopic methods, including 1D and 2D nuclear magnetic resonance (NMR) techniques, high-resolution mass spectrometry (HRMS), and chemical methods. The cytotoxic activities of the isolates (1 and 2) were evaluated by determining their inhibitory effects on four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15) and a human normal cell line (HUVEC) using a sulforhodamine B (SRB) bioassay. Compounds 1 and 2 showed cytotoxicity against tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15) with IC(50) values ranging from 6.3 to 26.9 μM and exhibited lower activity against the normal cell line (HUVEC) with IC(50) values ranging from 27.1 to 28.8 μM, suggesting selective toxicity among tumor and normal cells.

Furostanol saponins from the rhizomes of Dioscorea japonica and their effects on NGF induction

The rhizome of Dioscorea japonica is a food and medicinal source known as 'San Yak' in Korea. Two new furostanol saponins, coreajaponins A (1) and B (2), together with 10 known compounds (3-12) were isolated from the rhizomes of D. japonica. Their structures were determined by spectroscopic methods, including 1D and 2D NMR techniques, HRMS, and chemical methods. Nerve growth factor (NGF), a crucial factor for neuronal survival and differentiation, can potentially improve neurodegenerative diseases and diabetic polyneuropathy. We evaluated the effects of isolates (1-12) on NGF induction in a C6 rat glioma cell line. Coreajaponin B (2) upregulated NGF content without significant cell toxicity, as did 6, 8, 9, and 11.

New cytotoxic tetrahydroprotoberberine-aporphine dimeric and aporphine alkaloids from Corydalis turtschaninovii

Two new tetrahydroprotoberberine-aporphine dimeric alkaloids, corydaturtschines A (1) and B (2), and a new aporphine derivative, ethyl glausuccinate (3), together with 13 known protoberberine (4-16) and nine known aporphine alkaloids (17-25), were isolated from the tubers of Corydalis turtschaninovii. The structures of these new compounds were determined through spectral analyses, including extensive 2D-NMR data. The absolute configurations of the compounds were clarified by CD spectroscopic studies. The isolated compounds were tested for their cytotoxicity against four human cancer cell lines in vitro using a sulforhodamine B bioassay.

188Re-tin-colloid as a new therapeutic agent for rheumatoid arthritis

Radiation synovectomy is a useful treatment modality in patients with refractory synovitis. We have developed a 188Re-tin-colloid as a new radiopharmaceutical agent and investigated its efficacy and safety in patients with rheumatoid arthritis. Radiation synovectomy was performed using 188Re-tin-colloid in 22 knees from 21 rheumatoid arthritis patients refractory to intra-articular corticosteroid injection. The efficacy and safety of administration of 370-1110 MBq of 188Re-tin-colloid were evaluated after 1, 3, 6, 9 and 12 months. Pain intensity on a visual analogue scale decreased significantly 12 months after therapy (mean+/-SD: 68.0+/-26.1 mm vs. 25.1+/-23.4 mm; P=0.0001 by the paired t-test). Pain decreased in 19 cases (86.3%), joint tenderness improved in 14 cases (63.6%) and joint swelling was reduced in all cases (100%). 188Re-tin-colloid was safe. The residual activity of 188Re in the blood was 0.077%+/-0.25% of the injected dose. The radioactivity of 188Re in the urine was 0.14%+/-0.13% of the injected dose. Transient reactive synovitis was observed in 18 cases (81.8%). No clinical side-effects or abnormalities in leucocyte count, platelet count, liver function tests or urine analysis were observed in any patient. In conclusion, in this first study of radiation synovectomy using 188Re-tin-colloid for patients with rheumatoid arthritis, the treatment resulted in the improvement of arthritis and was well tolerated.

Effects of taurine on cerulein-induced acute pancreatitis in the rat

Taurine, or 2-aminoethane sulfonic acid, is an intracellular amino acid and has been suggested to have a function in protecting biological systems from oxidative tissue damage. The aim of this study was to determine the effect of taurine against cerulein-induced acute pancreatitis in rats. Acute pancreatitis was induced by administering three subcutaneous injections of cerulein (40 microg/kg body weight) at 1-hour intervals, while taurine was administered intravenously at graded doses (30, 100, or 300 mg/kg, respectively) following the first cerulein injection. The severities of pancreatitis and lung injury were determined by measuring biochemical parameters, tissue myeloperoxidase (MPO), and histological changes. To clarify the mechanism of taurine, serum IL-1beta and TNF-alpha levels and tissue concentrations of malondialdehyde (MDA) were evaluated. In cerulein-induced acute edematous pancreatitis, treatment with taurine significantly decreased hyperamylasemia, tissue MPO, pancreatic edema, and the extent of pancreatic and pulmonary injury. Taurine decreased MDA concentration in the pancreas and lung, but not the serum cytokine concentration. We would conclude that taurine has beneficial effects in cerulein-induced acute pancreatitis and lung injuries by preventing the production of oxygen free radicals.

Apicidin, an inhibitor of histone deacetylase, prevents H-ras-induced invasive phenotype

Cancer metastasis represents the most important cause of cancer death and agents that may inhibit tumor cell invasion have been extensively pursued. In the present study, we have examined the anti-invasive effect of apicidin [cyclo(N-O-methyl-L-tryptophanyl-L-isoleucinyl-D-pipecolinyl -L-2-amin o-8-oxodecanoyl)], a fungal metabolite that was identified as an antiprotozoal agent known to inhibit parasite histone deacetylase (HDAC). We show that apicidin significantly inhibits H-ras-induced invasive phenotype of MCF10A human breast epithelial cells in parallel with a specific downregulation of matrix metalloproteinase (MMP)-2, but not MMP-9. We also show that apicidin induces a morphological reversal and growth inhibition of H-ras MCF10A cells similar to that induced by other HDAC inhibitors. Taken in conjunction with the fact that uncontrolled ras activation is probably the most common genetic defect in human cancer cells, our data showing the anti-invasive and detransforming activities of apicidin in H-ras-transformed MCF10A cells may suggest a potential use of HDAC inhibitors for treatment of cancer.

Protective effect of taurine on TNBS-induced inflammatory bowel disease in rats

We had previously reported that the protective effect of taurine against indomethacin-induced gastric mucosal injury was due to its antioxidant effects, which inhibited lipid peroxidation and neutrophil activation. In this study, we examined the effect of taurine on reducing the inflammatory parameters of trinitrobenzene sulfonic acid (TNBS)-induced inflammatory bowel disease (IBD) in rats. In order to induce IBD, ethanolic TNBS was given to rats intracolonically. Then they received 500 mg/kg/day of taurine orally and were sacrificed one week after IBD induction. While ulceration and inflammation of distal colon with formation of granuloma in the vehicle-treated IBD rats two days after administration of TNBS were observed, treatment with taurine ameliorated colonic damage and decreased the incidence of diarrhea and adhesion. Also, colon weight as an index of tissue edema, which was markedly increased in the IBD rats, became significantly lower after taurine treatment. Myeloperoxidase (MPO) activity in the vehicle-treated IBD rats was substantially increased, compared with that of normal control. The taurine-treated animals significantly reduced MPO activity (35% lower) when compared with that of the vehicle-treated animals. Taurine treatment decreased both basal and formyl-methionyl leucyl phenylalanine-stimulated reactive oxygen generation from colonic tissue in the IBD rats. These results suggest that the administration of taurine reduce the inflammatory parameters in this IBD rat model by increasing defending capacity against oxidative damage.