The effect of burdock leaf fraction on adhesion, biofilm formation, quorum sensing and virulence factors of Pseudomonas aeruginosa.

AIMS: This study aimed to evaluate the effect of a fraction of burdock (Arctium lappa L.) leaf on the initial adhesion, biofilm formation, quorum sensing and virulence factors of Pseudomonas aeruginosa. METHODS AND RESULTS: Antibiofilm activity of the burdock leaf fraction was studied by the method of crystal violet staining. When the concentration of the burdock leaf fraction was 2·0 mg ml-1 , the inhibition rates on biofilm formation of P. aeruginosa were 100%. The burdock leaf fraction was found to inhibit the formation of biofilm by reducing bacterial surface hydrophobicity, decreasing bacterial aggregation ability and inhibiting swarming motility. Interestingly, the burdock leaf fraction inhibited the secretion of quorum-sensing (QS) signalling molecule 3-oxo-C12-HSL and interfered quorum sensing. Moreover, the QS-regulated pyocyanin and elastase were also inhibited. Chemical composition analysis by UPLC-MS showed 11 active compounds in the burdock leaf fraction. CONCLUSIONS: The burdock leaf fraction significantly inhibited the formation of biofilm and quorum sensing, as well as significantly decreased the content of virulence factors. SIGNIFICANCE AND IMPACT OF THE STUDY: This study introduces a natural and effective bacterial biofilm inhibitor, which could also significantly decrease the content of virulence factors and the drug resistance of P. aeruginosa.

[Preventive and therapeutic effects of compound ginkgo extract in rats with nonalcoholic steatohepatitis induced by high-fat, high-fructose diet].

Objective: To establish a rat model of nonalcoholic steatohepatitis (NASH), and to investigate the preventative and therapeutic effects of compound ginkgo extract against NASH. Methods: A total of 60 male Sprague-Dawley rats were fed with high-fat feed and 10% fructose water for 24 weeks to establish the rat model of NASH. The general behaviors of the rats were observed, and the body weight was recorded. Blood samples from the inferior vena cava and the liver were collected after the last administration to measure serum total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), as well as liver function parameters. The liver index was calculated, HE staining was performed to observe liver histopathological changes, and the total lipase activity and the levels of TC, TG, and free fatty acid (FFA) in liver tissue were measured. Results: After 24 weeks, compared with the normal group, the model group had a significantly faster increase in body weight, significant increases in serum levels of TC (2.20±0.52 mmol/L), TG (0.87±0.22 mmol/L), LDL-C (1.22±0.50 mmol/L), alanine aminotransferase (ALT) (129.4±44.7 U/L), and aspartate aminotransferase (AST) (209.3±42.8 U/L), liver index (3.62%±0.28%), and the levels of TC (4.42±1.39 mmol/mg.prot), TG (0.85±0.11 mmol/mg.prot), and FFA (644.78±36.65µmol/L) in liver tissue, and significant reductions in serum HDL-C level (0.58±0.11 mmol/L) and the activity of lipoprotein lipase (LPL) (9.95±1.64 U/mg.prot) and hepatic lipase (HL) (9.91±1.03 U/mg.prot) (allP< 0.01). In addition, the pathological results showed severe hepatocyte steatosis, varying degrees of inflammatory cell infiltration, exudation in the portal area, and necrosis of liver cells in the model group. After the intervention with compound ginkgo extract, there were significant reductions in serum levels of TC (1.78±0.21 mmol/L), TG (0.58±0.07 mmol/L), LDL-C (0.84±0.19 mmol/L), and ALT (84.1±17.1 U/L), AST (155.4±20.9 U/L), liver index (2.71%±0.15%), and the levels of TC (2.24±1.02 mmol/mg.prot), TG (0.46±0.11 mmol/mg.prot), and FFA (580.56±50.63µmol/L) in liver tissue, as well as significant increases in serum HDL-C level (0.68±0.10 mmol/L) and the activities of LPL (15.54±2.21 U/mg.prot) and HL (11.92±1.87 U/mg.prot) (P< 0.05 orP< 0.01). At the same time, it significantly reduced hepatomegaly in rats and improved fatty degeneration and degree of inflammation in liver cells. Conclusion: Compound ginkgo extract can prevent and treat NASH by correcting dyslipidemia, improving liver function and fatty degeneration in hepatocytes, and reducing the degree of inflammation, and its mechanism of action may be associated with increasing total lipase activity, reducing FFA in the liver, increasing the decomposition of TG, and reducing the synthesis of TG.

Dysregulation of Hypothalamo-Pituitary-Adrenocortical Axis in Overweight Female Diabetic Subjects is Associated with Downregulation of Corticosteroid Receptors and 11ß-HSD1 in the Brain.

The objective of this work was to assess hypothalamo-pituitary-adrenocortical (HPA) axis dysregulation in overweight diabetic women and investigate the possible mechanism using overweight diabetic rats. Twenty-two overweight diabetic women were recruited alongside 34 lean and 23 overweight healthy women serving as controls. Dexamethasone suppression test (0.25 mg DST) and low dose adrenocorticotropic hormone (ACTH) stimulation assay were used to evaluate the HPA axis activity. Then, high fat diet (HF) and STZ-induced diabetic rats were utilized to investigate the possible mechanism. After measurement of corticosterone circadian patterns and dexamethasone suppression levels, mRNA amounts of mineralocorticoid receptors (MR), glucocorticoid receptors (GR), and 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) were determined by real time PCR at hippocampus, hypothalamus, and pituitary levels. Overweight diabetic women showed impaired HPA axis with negative feedback efficacy (suppression ratio F-DEX%: 0.52±0.06% vs. 0.49±0.06% vs. 0.14±0.08%), as well as increased adrenal cortisol secretion response to low dose ACTH stimulation. Interestingly, F-DEX% was negatively correlated with BMI (r=- 0.323, p=0.003), waist circumference (r=- 0.319, p=0.004), and HbA1c (r=- 0.334, p=0.002). Stepwise linear regression analysis showed F-DEX% was significantly related to HbA1c level (ß=- 0.328, p=0.007) after adjusting for other covariates (age, BMI, waist circumference, SBP, TC, TG, and HOMA-IR). Furthermore, 11ß-HSD1, MR, and GR mRNA expression levels were reduced at pituitary level while GR expression was downregulated at hippocampus level in HF and HF+STZ rats. In conclusion, hyperactive HPA axis in overweight diabetic subjects may be associated with downregulation of 11ß-HSD1, MR, and GR in the brain.

First Report of 'Candidatus Liberibacter asiaticus' from Atalantia buxifolia in Guangdong, China.

Atalantia buxifolia (Poir.) Oliv., synonym Severinia buxifolia (Poir.) Ten. as commonly found in literature, is a common landscape plant and a popular Chinese medicinal herb known as Jiubingle or Dongfengjie. It remains unclear if this rutaceous plant could host 'Candidatus Liberibacter asiaticus', the pathogen of citrus Huanglongbing (HLB) in Guangdong, P. R. China. This information is important for HLB control in citrus because infected A. buxifolia could serve as a source of inoculum. In August of 1994, three A. buxifolia plants adjacent to a citrus experimental orchard of the South China Agricultural University at Guangzhou were found showing leaf mottle/yellowing symptoms. Two buds from each plant were grafted onto three mandarin trees (Citrus reticulata cv. Pongan) in a psyllid-proof screenhouse for indexing. By October of 1995, typical leaf mottle symptoms were observed in all three grafted trees compared with a healthy control. In March of 1996, one of the A. buxifolia plants was transferred to a screenhouse and has been maintained there. The leaf mottle/yellowing symptoms persisted but did not significantly affect plant growth. DNA was extracted from leaf samples in October 2006 by using the CTAB (cetyltrimethylammoniumbromide) method and assayed by nested-PCR using the general bacterial 16S rDNA primer set fDl/rD1 as the first round of amplification and primer set OI1/OI2c as second round amplification (1,3). After agarose gel electrophoresis and staining with ethidium bromide, an approximate 1.1-kb DNA band was detected in symptomatic samples but not healthy leaf samples of A. buxifolia and C. reticulata. XbaI digestion of the amplicons yielded approximate 500- and 600-bp fragments, characteristic of 'Ca. L. asiaticus'. Similarly, a standard PCR with primer set A5/J2 (3) yielded an approximate 700-bp DNA band characteristic of 'Ca. L. asiaticus' from symptomatic samples only. To our knowledge, this is the first report of graft transmission and PCR detection of 'Ca. L. asiaticus' from A. buxifolia in Guangdong, P. R. China. This work also confirms the findings from Taiwan (2) that A. buxifolia could serve as a source of 'Ca. L. asiaticus'. References: (1) X. Deng et al. Online publication. doi:10.1094/PHP-2007-0419-01-BR. Plant Health Progress, 2007. (2) T.-H. Hung et al. Eur. J. Plant Pathol. 107:183, 2001. (3) S. Jagoueix et al. Mol. Cell. Probes 10:43, 1996.

Two new flavanes and bioactive compounds from Daphne tangutica Maxim.

Two new flavanes, named daphneflavan B (1) and daphneflavan C (2), along with two known biflavonoids, daphnodorin D(1) (3) and daphnodorin D(2) (4), were isolated from the roots of Daphne tangutica Maxim. Their structures were established on the basis of chemical, physicochemical, and spectroscopic evidences. Two compounds 3 and 4 were noted to have the most marked antitumor activity in vivo assay.

Inducible expression and pharmacology of the human excitatory amino acid transporter 2 subtype of L-glutamate transporter.

1. In this study we have examined the use of the ecdysone-inducible mammalian expression system (Invitrogen) for the regulation of expression of the predominant L-glutamate transporter EAAT2 (Excitatory Amino Acid Transporter) in HEK 293 cells. 2. HEK 293 cells which were stably transformed with the regulatory vector pVgRXR (EcR 293 cells) were used for transfection of the human EAAT2 cDNA using the inducible vector pIND and a clone designated HEK/EAAT2 was selected for further characterization. 3. Na+-dependent L-glutamate uptake activity (3.2 pmol min-1 mg-1) was observed in EcR 293 cells and this was increased approximately 2 fold in the uninduced HEK/EAAT2 cells, indicating a low level of basal EAAT2 activity in the absence of exogenous inducing agent. Exposure of HEK/EAAT2 cells to the ecdysone analogue Ponasterone A (10 microM for 24 h) resulted in a > or = 10 fold increase in the Na+-dependent activity. 4. L-glutamate uptake into induced HEK/EAAT2 cells followed first-order Michaelis-Menten kinetics and Eadie-Hofstee transformation of the saturable uptake data produced estimates of kinetic parameters as follows; Km 52.7+/-7.5 microM, Vmax 3.8+/-0.9 nmol min-1 mg-1 protein. 5. The pharmacological profile of the EAAT2 subtype was characterized using a series of L-glutamate transport inhibitors and the rank order of inhibitory potency was similar to that described previously for the rat homologue GLT-1 and in synaptosomal preparations from rat cortex. 6. Addition of the EAAT2 modulator arachidonic acid resulted in an enhancement (155+/-5% control in the presence of 30 microM) of the L-glutamate transport capacity in the induced HEK/EAAT2 cells. 7. This study demonstrates that the expression of EAAT2 can be regulated in a mammalian cell line using the ecdysone-inducible mammalian expression system.

A new biologically active acylated triterpene saponin from Silene fortunei.

A new acylated triterpene-saponin (1), together with a mixture of the known jenisseensosides C and D, has been isolated from the roots of Silene fortunei. The structure of the new compound was established by chemical means and spectroscopic methods as 3-O-[beta-D-galactopyranosyl-(1-->2)-beta-D-glucuronopyranosyl]-28 -O- [[alpha-L-arabinopyranosyl-(1-->2)-alpha-L-arabinopyranosyl- (1-->3)-b eta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)]-[beta-D- glucopyranosyl-(1-->3)]-4-O-acetyl-beta-D-fucopyranosyl]quillaic acid. This saponin showed a significant enhancement of granulocyte phagocytosis in vitro.

[Studies on identification of yinchaihu by UV and IR].

OBJECTIVE: To study the identification of nine species of Yinchaihu derived from four genera of Caryophyllaceae, namely, Stellaria dichotoma var. lanceolata, St. dichotoma var. dichotoma, Arenaria juncea, A. capillaris var. glandulifera, Silene fortunei, Si. jenisseensis, Gypsophila pacifica, G. oldhamiana and G. licentiana. METHOD: UV and IR of alcohol extraction. RESULTS: The UV and IR spectra of these 9 plant roots have some difference. CONCLUSION: St. dichotoma var. lanceolata specified in the Chinese Pharmacopoeia can be distinguished from the other plants and all these 4 genera can be differentiated from one another by both UV and first derivative spectra. The genus Stellaria can be identified from the other 3 genera by IR.

Jennisseensosides C and D, biologically active acylated triterpene saponins from Silene jenisseensis.

We previously reported the isolation and structure elucidation of a new trans-p-methoxycinnamoyl triterpene-saponin along with its cis-p-methoxycinnamoyl isomer as an inseparable mixture from the roots of Silene jenisseensis. In a continuing study on this plant, two additional new acylated triterpene-saponins were obtained as an inseparable mixture. Their structures have been established by chemical means and spectroscopic methods including 1D and 2D homonuclear and heteronuclear correlation NMR spectroscopy as 3-O-[beta-D-galactopyranosyl-(1-->2)-beta-D-glucuronopyranosyl]-28 -O-[{alpha-L-rhamnopyranosyl-(1-->2)}-{4-O-trans-p-methoxycinnamoyl++ +}-beta-D-fucopyranosyl] quillaic acid and its cis-isomer, respectively. They showed a significant enhancement of the granulocyte phagocytosis in vitro.

[Studies on liposoluble constituents from the aerial parts of Siegesbeckia orientalis L].

Eight compounds were isolated from the aerial parts of Siegesbeckia orientalis L. and their structures were elucidated by spectroscopic methods(IR, EI-MS, 13C-NMR, 1H-NMR, 1H-1H COSY, 1H-1H NOESY and 1H-13C COSY). Compounds I and II are new natural products and named siegesesteric acid(I) and siegesetheric acid(II), their structures were confirmed as ent-17-acetoxy-18-isobutyryloxy-16(alpha)-kauran-19-oic acid(I) and ent-17-ethoxy-16(alpha)-(-)-kauran-19-oic acid(II). The others were identified as known compounds: ent-16 beta, 17-dihydroxy-kauran-19-oic acid (III), kirenol(IV), beta-sitosteryl glucoside(V), heneicosanol(VI), methyl arachidate(VII) and beta-sitosterol(VIII). These compounds, except kirenol and beta-sitosterol, were isolated for the first time from the title plant.

[Analysis of phenylethanoid glycosides of Herba cistanchis by RP-HPLC].

The Chinese drug "Rou Cong-rong" (Herba Cistanchis) is one of the commonly used drugs in Chinese traditional medicine. It is used to reinforce the vital function of kidney, especially that of the sexual organs and induce laxation, for the treatment of impotence, premature ejaculation in men, infertility, morbid leukorrhea, profuse metrorrhagia in women, and chronic constipation in the aged. This paper deals with the qualitative and quantitative analysis of phenylethanoid glycosides of four species and one variety of Genus Cistanche and 23 lots of commercial crude drugs of Herba Cistanchis by RP-HPLC. The results were as follows: the chemical constituents of Cistanche deserticola Ma, C. salsa (C. A. Mey) G. Beck, C. salsa var. albiflora P. F. Tu et Z. C. Lou and C. tubulosa were similar while those of C. sinensis were different from the others; the contents of echinacoside and acteoside of C. salsa, which were 2.13% and 1.51%, were the highest of the genus Cistanche. An ODS column (Alltima C18, 5 microns, 250 x 4.6 mm) was employed. Linear gradient elution of acetonitrile--1.5% acetic acid was used as mobile phase, and concentration of acetontrile was from 8% to 20% (0-60 min) in the qualitative analysis, and from 11.5 to 20% (0-35 min) in the quantitative analysis. The flow rate was 1.2 ml.min-1. The detection wavelength was set at 335 nm.

[Identification and survey of commercial crude drug of Herba Cistanchis].

This paper deals with the morphological identification, TLC analysis and survey of commercial crude drug of Herba Cistanchis (Genus Cistinche). This results provide authentic methods for the identification of Herba Cistanchis.

[Botanical origin of commercial samples of traditional Chinese drug xixin (Herba Aasari)].

It has been found out that amony the 158 samples of commercial drug. Xixin (Herba Asari) collected from 28 provinces/cities of China, only three guarters are derived from the species specified in the Chinese Pharmacopoeia and the rest are not. One hundred and eleven samples are derived from Asarum heterotropoides var. mandshuricum and are presently used in 26 provinces/cities, 25 samples are derived from A. himalaicum and used in 10 provinces, the other 22 samples are derived from 9 species such as A. sieboldii, A. forbesii, etc.

[Restricting effects of geologic background system on genuine crude drugs in Sichuan].

The distribution, growth, output and quality of genuine crude drugs are restricted by geologic background system (GBS), whose extensional vector system "rock-->soil-->medicinal plants" accomplishes the unity of geological grand cycle and biological pulmonary circulation. This article describes how genuine crude drugs in Sichuan, such as Coptis chinensis, etc. for example, are restricted by GBS.

Characterization of the receptor protein tyrosine phosphatase gene product PTP gamma: binding and activation by triphosphorylated nucleosides.

A full-length cDNA for a novel isoform of the human receptor tyrosine phosphatase gamma gene (PTPRG) was overexpressed in Sf9 insect cells, and the gene product, PTP gamma, was purified and characterized. The protein was expressed as a M(r) approximately 185,000 protein accompanied by a M(r) approximately 120,000 putative cleavage product on SDS-PAGE analysis. The protein undergoes N-linked glycosylation and constitutive phosphorylation of serine residues. When assayed for tyrosine-specific phosphatase activity, PTP gamma dephosphorylated myelin basic protein at a pH optimum of 7.5 and a Km of 12.6 microM; reduced carboxyamidomethylated and maleylated lysozyme (RCM-lysozyme) at a pH optimum of 6.0 and a Km of 12 microM; and p-nitrophenylphosphate with a pH optimum of 5.5 and a Km of 3.5 mM. Phosphatase activity was inhibited by ZnCl2 and sodium orthovanadate; Mg2+, Mn2+, and Ca2+ ions were ineffective. The partially purified form of the enzyme was allosterically activated by triphosphorylated nucleosides, with a preference for purines. This activation was prevented by Mg2+ addition and did not occur when a purified form of the enzyme was utilized, suggesting that its activation depends on specific activating factors or conformational constraints. Interestingly, PTP gamma protein was specifically bound by an ATP-agarose matrix through its intracellular domain, suggesting a link between binding of nucleotides and activation of the phosphatase.

Acylated triterpene saponins from Silene jenisseensis.

From the roots of Silene jenisseensis a new trans-p-methoxycinnamoyl triterpene saponin has been isolated along with its cis-p-methoxycinnamoyl isomer as an inseparable mixture. Their structures were established by chemical means and spectroscopic methods including 1D- and 2D-homonuclear and heteronuclear correlation NMR spectroscopy as 3-O-[beta-D-galactopyranosyl-(1 --> 2)-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl-(1 --> 2)-alpha-L-rhamnopyranosyl- (1 --> 2)-beta-D-4-O-trans-p-methoxycinnamoyl-fucopyranosyl] quillaic acid and its cis-isomer, respectively. They did not show any activity in the in vitro chemoluminescence granulocytes assay, but exhibited only a weak inhibitory effect in the cyclooxygenase inhibition assay.

[Effects of Chinese herbs on impaired lymphocyte functions after thermal injury in mice].

Four Chinese herbs were chosen for this study. They were Panax pseudoginseng wall (PPW), Loniconica japonica thunb (LJT), Polygonum cuspidatum (PC) and Jilin ginseng (JG). They were given from the 2nd to the 7th postburn day (PBD). The results showed that the response to antigen signal, the proliferative capacity, the interleukin II production function, and the antibody production ability by lymphocytes in control burned mice were more noticeably reduced than that in the normal mice. The PPW, LJT, PC might restore all the impaired functions in different degrees. The JG showed no effect at all.

[Chemical components of volatile oil from Echinops grijisii Hance].

The volatile oil obtained from Echinops grijisii roots was analysed by GC-MS method. Twenty four constituents have been identified from the oil, among which cis-beta-farnesene and 5-(3-buten-1-ynyl)bithiophene are the main ones.

[Herbalogical studies on rou congrong (herba Cistanchis)].

This paper deals with the investigation of the original plants of Rou Congrong and Cao Congrong recorded in the herbalogical works of the past dynasties. The results have shown that Rou Congrong is the dried fleshy stem of Cistanche deserticola and C. salsa, and Cao Congrong is the dried fleshy stem of Orobanche coerulescens. The substitutes and false drugs of Rou Congrong were also investigated.

[Comparative analysis of several treatment methods for severe congestive heart failure].

UNLABELLED: Western medicines (WM) and the combining WM-TCM were used to treat congestive heart failure (CHF). The three groups of WM were: Digoxin with dihydro-chlorothiazide, captopril with nifedipium, and dobutamine. The three groups of combining WM-TCM were: the above-mentioned three groups of WM with Jisen Shenqi Pill (JSSQ) respectively. The result observed: Total effective rate was 82%, marked effective rate was 43%, the rates of the WM groups were 77% and 36% respectively, and the groups of combining WM-TCM were 88% and 53%. Total mortality was 8.66% (the WM groups was 11.76%, the groups of combining WM-TCM 5%). Cardio-function indexes observed in the groups of combining WM-TCM were obviously improved, including HR, SV, CI, EF, FS and A/E (P < 0.01). HR, CI and SV in the groups of WM were also significantly improved (P < 0.05) except for EF, FS and A/E (P > 0.05). CONCLUSIONS: (1) The treatment of CHF should depend on various conditions and different symptoms in selecting medicines, so that individual treatment could reach the optimal effects. (2) The treatment method of combining WM-TCM could significantly promote effective rate, reduce toxic and side-effects and lower the rate of mortality. (3) JSSQ could obviously improve the function of ventricular diastole and its mechanism might be that the reduced density of beta-receptor was increased.