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Purpose: As the demand for natural cosmetics increases, properly managing production and quality control should be prioritized. Chlorogenic acid (CGA), epicatechin gallate (ECG), and rosmarinic acid (RMA) were selected to validate the cosmetic composite LOL, a mixture of 50% EtOH extract of Ligularia stenocephala (LS), Orostachys japonica (OJ), and Lavandula angustifolia (LA). Methods: Highperformance liquid chromatography with a diode array detector (HPLC-DAD) was used to simultaneously analyze the three LOL compounds from LOL (Ligularia stenocephala , Orostachys japonica , Lavandula angustifolia ). Linearity, accuracy, and precision analyses were performed using HPLC-DAD, and the anti-oxidative effects were evaluated through a 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay. Results: All three extracts showed a high DPPH radical-scavenging effect, and the detected marker compounds showed significant linearity (R2≥0.9997). The limit of detection (LOD) of CGA, ECG, and RMA was 0.83 μg/mL, 0.33 μg/mL, and 0.20 μg/mL, respectively. Meanwhile, the limit of quantification (LOQ) of CGA, ECG, and RMA was 2.51 μg/mL, 0.99 μg/mL, and 0.61 μg/mL, respectively. Method validation showed acceptable precision (intra-and inter-day precision, CGA, ECG, and RMA, 1.77, 1.42, 0.80% and 1.09, 0.72, 1.42%, respectively) and recovery (CGA, ECG, and RMA, 102.00%–117.78%, 94.40%-108.06%, and 93.79%–107.05%). Conclusion: The contents of the three markers were 13.99 μg/mL CGA, 8.28 μg/mL ECG, and 8.40 μg/mL of RMA, respectively. This study also suggests that the developed method can validate the LOL cosmetic composition quality control process.

Purpose: Recently, the demand for natural extracts and naturally derived ingredients from core raw materials has increased in the cosmetic industry, but their manufacturing and quality control standards are not sufficiently established. This study aims to standardize the compositions of marker compounds from natural cosmetics using ethanol extracts of Chrysanthemum indicum (CI) and Cymbopogon cirtratus (CC). The method is then validated. Methods: In liquid chromatography (LC)/mass spectrometry, astragalin and p -coumaric acid were determined as the marker compounds for quantitative analysis. The performances (linearity, accuracy, and precision) of these two marker components were simultaneously analyzed in a mixture of both natural products using high-performance liquid chromatography with a diode array detector (HPLC-DAD). Results: The marker compounds of CI and CC in the extracts were determined as astragalin and p -coumaric acid, respectively. The detected marker compounds from the CI and CC showed significant linearity (R2≥0.9999). The astragalin and p -coumaric acid markers achieved limits of detection of 1.20 and 0.07 ng/mL, respectively, and limits of quantification of 3.59 and 0.22 ng/mL, respectively. The marker concentrations were 0.24 μg/mL in CI and 1.55 μg/mL in CC. Conclusion: This study suggests that the developed method may be an important basic data for the manufacturing and quality control of natural cosmetic.

Alzheimer's disease (AD) is linked to an extensive neuron loss via accumulation of amyloid-beta (Aβ) as senile plaques associated with reactive astrocytes and microglial activation in the brain. The objective of this study was to assess the therapeutic effect of WS-5 ethanol extract in vitro and in vivo against Aβ-induced AD in mice and to identify the extract’s active constituents. In the present study, WS-5 exerted a significant inhibitory effect on acetylcholinesterase (AChE). Analysis by transmission electron microscopy (TEM) revealed that WS-5 prevented Aβ oligomerization via inhibition of Aβ1-42 aggregation. Evaluation of antioxidant activities using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) demonstrated that WS-5 possessed a high antioxidant activity, which was confirmed by measuring the total antioxidant status (TAS). Furthermore, the anti-inflammatory properties of WS-5 were examined using lipopolysaccharide-stimulated BV-2 microglial cells. WS-5 significantly inhibited the lipopolysaccharide–induced production of nitric oxide and two proinflammatory cytokines, TNF-α and IL-6. The memory impairment in mice with Aβ-induced AD was studied using the Morris water maze and passive avoidance test. Immunohistochemistry was performed to monitor pathological changes in the hippocampus and cortex region of the mouse brain. The animal study showed that WS-5 (250 mg/kg) treatment improved learning and suppressed memory impairment as well as reduced Aβ plaque accumulation in Aβ-induced AD. HPLC analysis identified the extract’s active compounds that exert anti-AChE activity. In summary, our findings suggest that WS-5 could be applied as a natural product therapy with a focus on neuroinflammation-related neurodegenerative disorders.

In order to discover lifespan-extending compounds made from natural resources, activity-guided fractionation of Zingiber officinale Roscoe (Zingiberaceae) ethanol extract was performed using the Caenorhabditis elegans (C. elegans) model system. The compound 6-gingerol was isolated from the most active ethyl acetate soluble fraction, and showed potent longevity-promoting activity. It also elevated the survival rate of worms against stressful environment including thermal, osmotic, and oxidative conditions. Additionally, 6-gingerol elevated the antioxidant enzyme activities of C. elegans, and showed a dose-depend reduction of intracellular reactive oxygen species (ROS) accumulation in worms. Further studies demonstrated that the increased stress tolerance of 6-gingerol-mediated worms could result from the promotion of stress resistance proteins such as heat shock protein (HSP-16.2) and superoxide dismutase (SOD-3). The lipofuscin levels in 6-gingerol treated intestinal worms were decreased in comparison to the control group. No significant 6-gingerol-related changes, including growth, food intake, reproduction, and movement were noted. These results suggest that 6-gingerol exerted longevity-promoting activities independently of these factors and could extend the human lifespan.

Background: A set of logical criteria that can accurately identify and verify the cultivation region of raw materials is a critical tool for the scientific management of traditional herbal medicine. Methods and Results: Volatile compounds were obtained from 19 and 32 samples of Angelica gigas Nakai cultivated in Korea and China, respectively, by using steam distillation extraction. The metabolites were identified using GC/MS by querying against the NIST reference library. Data binning was performed to normalize the number of variables used in statistical analysis. Multivariate statistical analyses, such as Principal Component Analysis (PCA), Partial Least Squares-Discriminant Analysis (PLS-DA), and Orthogonal Partial Least Squares-Discriminant Analysis (OPLS-DA) were performed using the SIMCA-P software. Significant variables with a Variable Importance in the Projection (VIP) score higher than 1.0 as obtained through OPLS-DA and those that resulted in p-values less than 0.05 through one-way ANOVA were selected to verify the marker compounds. Among the 19 variables extracted, styrene, -pinene, and -terpinene were selected as markers to indicate the origin of A. gigas. Conclusions: The statistical model developed was suitable for determination of the geographical origin of A. gigas. The cultivation regions of six Korean and eight Chinese A. gigas. samples were predicted using the established OPLS-DA model and it was confirmed that 13 of the 14 samples were accurately classified.

It is believed that traditional Korean medicines can be managed more scientifically through the development of logical criteria to verify their region of cultivation, and that this could contribute to the advancement of the traditional herbal medicine industry. This study attempted to determine such criteria for Sansuyu. The volatile compounds were obtained from 20 samples of domestic Corni fructus (Sansuyu) and 45 samples of Chinese Sansuyu by steam distillation. The metabolites were identified in the NIST Mass Spectral Library via the obtained gas chromatography/ mass spectrometer (GC/MS) data of 53 training samples. Data binning at 0.2 min intervals was performed to normalize the number of variables used in the statistical analysis. Multivariate statistical analyses, such as principle component analysis (PCA), partial least squares-discriminant analysis (PLS-DA), and orthogonal partial least squares-discriminant analysis (OPLS-DA) were performed using the SIMCA-P software package. Significant variables with a variable importance in the projection (VIP) score higher than 1.0 were obtained from OPLS-DA, and variables that resulted in a p-value of less than 0.05 through one-way ANOVA were selected to verify the marker compounds. Finally, among the 11 variables extracted, 1-ethylbutyl-hydroperoxide (9.089 min), nonadecane (20.170 min), butylated hydroxytoluene (25.319 min), 5β,7βH,10α-eudesm-11-en-1α-ol (25.921 min), 7,9-bis(2-methyl-2-propanyl)-1-oxaspiro(4.5)deca-6,9- diene-2,8-dione (34.257 min), and 2-decyldodecyl-benzene (54.717 min) were selected as markers to indicate the origin of Sansuyu. The statistical model developed was suitable for the determination of the geographical origin of Sansuyu. The cultivation areas of four Korean and eight Chinese Sansuyu samples were predicted via the established OPLS- DA model, and it was confirmed that 11 of the 12 samples were accurately classified. 요약 : 생약의 원산지를 판별하는 논리적인 일련의 기준을 개발한다면, 현재 유통되는 한약을 좀 더 과 학적으로 관리 할 수 있을 것이다. 이러한 노력은 전통적인 한약 산업 발전에 기여할 것이라고 사료된다. 산수유의 원산지 판별법을 개발하기 위해, 본 연구에서는 우선 국산 산수유와 중국산 산수유를 각각 수 증기 증류하고 이 때 얻은 휘발성분을 GC/MS를 이용하여 분석하였다. NIST mass spectral library의 데이

Alzheimer's disease (AD), which is characterized by progressive cognitive impairment, is the most common neurodegenerative disease. Here, we investigated the preventive effect of a phosphodiesterase III inhibitor, cilostazol against cognitive decline in AD mouse model. In vitro studies using N2a cells stably expressing human amyloid precursor protein Swedish mutation (N2aSwe) showed that cilostazol decreased the amyloid β (Aβ) levels in the conditioned medium and cell lysates. Cilostazol attenuated the expression of ApoE, which is responsible for Aβ aggregation, in N2aSwe. Intracerebroventricular injection of Aβ(25-35) in C57BL/6J mice resulted in increased immunoreactivity of Aβ and p-Tau, and microglia activation in the brain. Oral administration of cilostazol for 2 weeks before Aβ administration and once a day for 4 weeks post-surgery almost completely prevented the Aβ-induced increases of Aβ and p-Tau immunoreactivity, as well as CD11b immunoreactivity. However, post-treatment with cilostazol 4 weeks after Aβ administration, when Aβ was already accumulated, did not prevent the Aβ-induced neuropathological responses. Furthermore, cilostazol did not affect the neprilysin and insulin degrading enzymes involved in the degradation of the Aβ peptide, but decreased ApoE levels in Aβ-injected brain. In addition, cilostazol significantly improved spatial learning and memory in Aβ-injected mice. The findings suggest that a phosphodiesterase III inhibitor, cilostazol significantly decreased Aβ accumulation and improved memory impairment induced by Aβ(25-35). The beneficial effects of cilostazol might be explained by the reduction of Aβ accumulation and tau phosphorylation, not through an increase in Aβ degradation but via a significant decrease in ApoE-mediated Aβ aggregation. Cilostazol may be the basis of a novel strategy for the therapy of AD.

Proteolytic processing of amyloid precursor protein (APP) by beta- and gamma-secretases generates beta-amyloid (Abeta) peptides, which accumulate in the brains of individuals affected by Alzheimer disease. Detergent-resistant membrane microdomains (DRM) rich in cholesterol and sphingolipid, termed lipid rafts, have been implicated in Abeta production. Previously, we and others reported that the four integral subunits of the gamma-secretase associate with DRM. In this study we investigated the mechanisms underlying DRM association of gamma-secretase subunits. We report that in cultured cells and in brain the gamma-secretase subunits nicastrin and APH-1 undergo S-palmitoylation, the post-translational covalent attachment of the long chain fatty acid palmitate common in lipid raft-associated proteins. By mutagenesis we show that nicastrin is S-palmitoylated at Cys(689), and APH-1 is S-palmitoylated at Cys(182) and Cys(245). S-Palmitoylation-defective nicastrin and APH-1 form stable gamma-secretase complexes when expressed in knock-out fibroblasts lacking wild type subunits, suggesting that S-palmitoylation is not essential for gamma-secretase assembly. Nevertheless, fractionation studies show that S-palmitoylation contributes to DRM association of nicastrin and APH-1. Moreover, pulse-chase analyses reveal that S-palmitoylation is important for nascent polypeptide stability of both proteins. Co-expression of S-palmitoylation-deficient nicastrin and APH-1 in cultured cells neither affects Abeta40, Abeta42, and AICD production, nor intramembrane processing of Notch and N-cadherin. Our findings suggest that S-palmitoylation plays a role in stability and raft localization of nicastrin and APH-1, but does not directly modulate gamma-secretase processing of APP and other substrates.

Systemic lupus erythematosus (SLE) is characterized by inflammatory and dysregulatory immune responses including overactive B cells, overproduction of proinflammatory cytokines, and T cell hyperactivity. PGE(2) modulates a variety of immune processes at sites of inflammation, including production of inflammatory cytokines. However, the role of PGE(2) in dysregulatory inflammatory and immune responses in lupus remains unclear. We investigated whether PGE(2) mediates production of inflammatory cytokines in pristane-induced lupus BALB/c mice. Our results showed that levels of serum and BAL PGE(2) and LPS-stimulated production of PGE(2) by peritoneal macrophages were remarkably increased in pristane-induced lupus mice compared to healthy controls. Exogenous PGE(2) enhanced production of IL-6, IL-10, and NO but decreased TNF-alpha by macrophages and augmented IFN-gamma, IL-6, and IL-10 by splenocytes from pristane-induced lupus mice compared to healthy controls. Exogenous PGE(2) also enhanced production of IFN-gamma, IL-6, and IL-10 by thymocytes from pristane-induced lupus mice. Indomethacin (Indo), a PGE(2) synthesis inhibitor, greatly inhibited LPS-induced production of IL-6 and IL-10 by macrophages from pristane-induced lupus mice, while enhanced TNF-alpha. Indo remarkably inhibited Con A-increased production of IFN-gamma, IL-6, and IL-10 by splenocytes and thymocytes from pristane-induced lupus mice. Therefore, our findings suggest that endogenous PGE(2) may mediate dysregulation of production of proinflammatory cytokines, such as IL-6, IL-10, and IFN-gamma, and NO in pristane-induced lupus mice.

With the goal of developing Alzheimer's disease therapeutics, we have designed and synthesized new piperidine derivatives having dual action of acetylcholinesterase (AChE) and beta-amyloid peptide (Abeta) aggregation inhibition. For binding with the catalytic site of AChE, an ester with aromatic group was designed, and for the peripheral site, another aromatic group was considered. And for intercalating amyloid-beta oligomerization, long and linear conformation with a lipophilic group was considered. The synthetic methods employed for the structure with dual action depended on alcohols with an aromatic ring and the substituted benzoic acids, which are esterificated in the last step of the synthetic pathway. We screened these new derivatives through inhibition tests of acetylcholinesterase, butyrylcholinesterase (BChE), and Abeta(1-42) peptide aggregation, AChE-induced Abeta(1-42) aggregation. Our results displayed that compound 12 showed the best inhibitory potency and selectivity of AChE, and 29 showed the highest selectivity of BChE inhibition. Compounds 15 and 12 had inhibitory activities against Abeta(1-42) aggregation and AChE-induced Abeta aggregation. In the docking model, we confirmed that 4-chlorobenzene of 12 plays the parallel pi-pi stacking against the indole ring of Trp84 in the bottom gorge of AChE. Because the benzyhydryl moiety of 12 covered the peripheral site of AChE in a funnel-like shape, 12 showed good inhibitory potency against AChE and could inhibit AChE-induced Abeta(1-42) peptide aggregation.

A new antimicrobial peptide, cryptonin, was isolated and characterized from the adult Korean blackish cicada, Cryptotympana dubia. It consists of 24 amino acid residues and has a molecular weight of 2,704 Da on mass spectroscopy. The predicted α-helical structure analysis and increased helix percent in 40% trifloroethanol of cryptonin suggests that it belongs to the typical linear α-helix forming peptide. Binding of the biotin-labeled cryptonin at the surface of E. coli cells and increased influx of propidium iodide in E. coli after cryptonin treatment indicates that it kills microbial cells by binding bacterial cell surfaces and disrupting the cell permeability. Cryptonin showed strong antibacterial (MIC 1.56–25 μg/ml) and antifungal (MIC 3.12–50 μg/ml) activities against tested bacteria and fungi including two antibiotic-resistant bacterial strains; methicilin-resistant S. aureus and vancomycin-resistant Enterococci (MIC 25 μg/ml, each). Arch. Insect Biochem. Physiol. 66:204–213, 2007. © 2007 Wiley-Liss, Inc.

Proteolytic processing of amyloid precursor protein generates beta-amyloid (Abeta) peptides that are deposited in senile plaques in brains of aged individuals and patients with Alzheimer's disease. Presenilins (PS1 and PS2) facilitate the final step in Abeta production, the intramembranous gamma-secretase cleavage of amyloid precursor protein. Biochemical and pharmacological evidence support a catalytic or accessory role for PS1 in gamma-secretase cleavage, as well as a regulatory role in select membrane protein trafficking. In this report, we demonstrate that PS1 is required for maturation and cell surface accumulation of nicastrin, an integral component of the multimeric gamma-secretase complex. Using kinetic labeling studies we show that in PS1(-/-)/PS2(-/-) cells nicastrin fails to reach the medial Golgi compartment, and as a consequence, is incompletely glycosylated. Stable expression of human PS1 restores these deficiencies in PS1(-/-) fibroblasts. Moreover, membrane fractionation studies show co-localization of PS1 fragments with mature nicastrin. These results indicate a novel chaperone-type role for PS1 and PS2 in facilitating nicastrin maturation and transport in the early biosynthetic compartments. Our findings are consistent with PS1 influencing gamma-secretase processing at multiple steps, including maturation and intracellular trafficking of substrates and component(s) of the gamma-secretase complex.

Neuroinflammation is implicated for amyloidogenesis. Sulfur compounds extracted from garlic have been shown to have anti-inflammatory properties. Previously, we have investigated that thiacremonone, a sulfur compound isolated from garlic has anti-inflammatory effects. To investigate thiacremonone's potential effect on anti-neuroinflammation and anti-amyloidogenesis, 4 week old ICR mice were given different doses of thiacremonone (1, 3, and 10 mg/kg) in drinking water for 1 month and received intraperitoneal injection of lipopolysaccharide (LPS) (250 μg/kg/day) at last 7 days of treatment. Our data show thiacremonone decreased LPS-induced memory impairment, glial activation, pro-inflammatory mediators' expression, and amyloidogenesis. In an in vitro study, we obtained similar results, with thiacremonone (1, 2, and 5 μg/ml) effectively decreased LPS (1 μg/ml)-induced glial activation and inflammatory mediators generation which are implicated in amyloidogenesis. Our data also demonstrated that thiacremonone inhibited LPS-induced amyloidogenesis in cultured astrocytes and microglial BV-2 cells. NF-κB, a critical transcriptional factor regulating not only inflammation but also amyloid-β generation, was inhibited by thiacremonone via blocking of phosphorylation of IκBα in mice brain as well as cultured astrocytes and microglial BV-2 cells. These results indicated that the anti-inflammatory compound, thiacremonone, inhibited neuroinflammation and amyloidogenesis through inhibition of NF-κB activity, and thus could be applied for intervention of inflammation-related neurodegenerative disease including Alzheimer's disease.

Presenilin 1 (PS1) and presenilin 2 play a critical role in the gamma-secretase processing of amyloid precursor protein (APP) and Notch1. Here, we investigate maturation and intracellular trafficking of APP and other membrane proteins in cells expressing an experimental PS1 deletion mutant (deltaM1,2). Stable expression of deltaM1,2 impairs gamma-secretase processing of Notch1 and delays Abeta secretion. Kinetic studies show enhanced O-glycosylation and sialylation of holo-APP and marked accumulation of APP COOH-terminal fragments (CTFs). Surface biotinylation, live staining, and trafficking studies show increased surface accumulation of holo-APP and CTFs in deltaM1,2 cells resulting from enhanced surface delivery of newly synthesized APP. Expression of a loss-of-function PS1 mutant (D385A) or incubation of cells with gamma-secretase inhibitors also increases surface levels of holo-APP and CTFs. In contrast to APP, glycosylation and surface accumulation of another type I membrane protein, nicastrin, are markedly reduced in deltaM1,2 cells. Finally, expression of deltaM1,2 results in the increased assembly and surface expression of nicotinic acetylcholine receptors, illustrating that PS1's influence on protein trafficking extends beyond APP and other type I membrane protein substrates of gamma-secretase. Collectively, our findings provide evidence that PS1 regulates the glycosylation and intracellular trafficking of APP and select membrane proteins.

Presenilins (PS1/PS2) play a critical role in proteolysis of beta-amyloid precursor protein (beta APP) to generate beta-amyloid, a peptide important in the pathogenesis of Alzheimer's disease. Nevertheless, several regulatory functions of PS1 have also been reported. Here we demonstrate, in neuroblastoma cells, that PS1 regulates the biogenesis of beta APP-containing vesicles from the trans-Golgi network and the endoplasmic reticulum. PS1 deficiency or the expression of loss-of-function variants leads to robust vesicle formation, concomitant with increased maturation and/or cell surface accumulation of beta APP. In contrast, release of vesicles containing beta APP is impaired in familial Alzheimer's disease (FAD)-linked PS1 mutant cells, resulting in reduced beta APP delivery to the cell surface. Moreover, diminution of surface beta APP is profound at axonal terminals in neurons expressing a PS1 FAD variant. These results suggest that PS1 regulation of beta APP trafficking may represent an alternative mechanism by which FAD-linked PS1 variants modulate beta APP processing.

Presenilin 1 (PS1) and presenilin 2 (PS2) are polytopic membrane proteins that are mutated in the majority of early onset familial Alzheimer's disease (FAD) cases. Two lines of evidence establish a critical role for PS in the production of beta-amyloid peptides (Abeta). FAD-linked PS mutations elevate the levels of highly amyloidogenic Abeta ending at residue 42 (Abeta42), and cells with ablated PS1 alleles secrete low levels of Abeta. Several recent reports have shown that the hydrophilic loop (HL) domain, located between transmembrane domains 6 and 7, contains sites for phosphorylation, caspase cleavage, and sequences that bind several PS-interacting proteins. In the present report, we examined the metabolism of PS polypeptides lacking the HL domain and the influence of these molecules on Abeta production. We report that the deletion of the HL domain does not have a deleterious effect on the regulated endoproteolysis of PS, saturable accumulation of PS fragments, or the self-association of PS fragments. Abeta production was not significantly altered in cells expressing HL-deleted PS polypeptides compared with cells expressing full-length PS. Importantly, deletion of the HL domain did not affect FAD mutation-mediated elevation in the production of Abeta42. Furthermore, the deletion of the HL domain did not impair the role of PS1 or PS2 in facilitating Notch processing. Thus, our results argue against a biologically or pathologically relevant role for the HL domain phosphorylation and caspase cleavage and the association of PS HL domain-interacting proteins, in amyloid precursor protein metabolism and Abeta production or Notch cleavage.

The effect of N-β-alanyl-5-S-glutathionyl-dopa (5-S-GAD), a compound originally isolated from Sarcophaga peregrina (a flesh fly) as an antibacterial substance, on protein phosphorylation was examined using v-src -transformed NIH3T3 cell lysates. 5-S-GAD was found to inhibit tyrosine phosphorylation of protein tyrosine kinase v-src, but not serine/threonine phosphorylation of protein kinase C. The potency of this compound was comparable to that of herbimycin A. Our results suggested that a substitution at position 5 of the catechol in 5-S-GAD with the sulfur of cysteine is essential for 5-S-GAD to inhibit protein tyrosine kinase v-src.

We purified a novel antibacterial substance from immunized adult Sarcophaga and determined its molecular structure to be N-beta-alanyl-5-S-glutathionyl-3,4-dihydroxyphenylalanine (5-S-GAD). We synthesized 5-S-GAD enzymatically from N-beta-alanyl-3, 4-dihydroxyphenylalanine (beta-Ala-Dopa) and reduced glutathione (GSH). The antibacterial activity of 5-S-GAD was found to be due to its production of H2O2. This is a novel antibacterial mechanism as it differs from the mechanisms of known antibacterial peptides. Two possible roles of 5-S-GAD in insect immunity, suppression of bacterial growth and activation of a Rel family transcription factor, are proposed.

We examined the inhibitory effects of N-beta-alanyl-5-S-glutathionyl-3,4-dihydroxyphenylalanine (5-S-GAD), a novel antibacterial substance from the immunized adult Sarcophaga peregrina (flesh fly), on protein phosphorylation using immune complexes of protein tyrosine kinases (PTKs) with anti-PTKs monoclonal antibody. We found that 5-S-GAD directly inhibited not only tyrosine phosphorylation of PTK p60(v-src), but also tyrosine phosphorylation of PTK p210(BCR-ABL). The inhibitory potency of 5-S-GAD was comparable to that of radicicol and herbimycin A of PTK inhibitor.