Salicylic acid positively regulates maize defenses against lepidopteran insects

In response to insect attack,plants use intricate signaling pathways,including phytohormones,such as jasmonate(JA),ethylene(ET),and salicylic acid(SA),to activate defenses.Maize(Zea mays)is one of the most important staple food crops around the world.Previous studies have shown that the JA and ET signaling play important roles in maize defense against insects,but little is known about whether and how SA regulates maize resistance to insect herbivores.In this study,we ectopically expressed the NahG(salicylate hydroxylase)gene in maize plants(NahG maize)to block the accumulation of SA.It was found that compared with the wild-type(WT)maize,the NahG-maize exhibited decreased resistance to the generalist insects Spodoptera litura and Spodoptera frugiperda and the specialist Mythimna separata,and the compromised resistance in the NahG maize was associated with decreased levels of defensive metabolites benzoxazinoids(Bxs)and chlorogenic acid(CA).Quantification of simulated S.litura feedinginduced JA,JA-isoleucine conjugate(JA-Ile),and ET in the WT and NahG maize indicated that SA does not regulate JA or JA-Ile,but positively controls ET.We provide evidence suggesting that the SA pathway does not crosstalk with the JA or the ET signaling in regulating the accumulation of Bxs and CA.Transcriptome analysis revealed that the bHLH,ERF,and WRKY transcription factors might be involved in SAregulated defenses.This study uncovers a novel and important phytohormone pathway in maize defense against lepidopterous larvae.

Investigating the mechanisms of isochorismate synthase:An approach to improve salicylic acid synthesis and increase resistance to Fusarium head blight in wheat

Salicylic acid(SA),a vital endogenous hormone,plays a crucial role in plant growth and the response to abiotic and biotic stress.Isochorismate synthase(ICS)and phenylalanine ammonia lyase(PAL)are critical rate-limiting enzymes for SA synthesis.Fusarium head blight(FHB)seriously threatens the safety of wheat production,but increasing the content of SA can enhance FHB resistance.However,the pathway of SA synthesis and regulation in wheat remains unknown.In this study,three wheat ICS(TaICSA,TaICSB,and TaICSD)were identified,and their functions were validated in vitro for isomerizing chorismate to isochorismate.The mutation of one or two homoeoalleles of TaICSA,TaICSB,and TaICSD in the wheat variety‘Cadenza’reduced SA levels under ultraviolet treatment and Fusarium graminearum infection,further enhancing sensitivity to FHB.Overexpression of TaICSA can significantly enhance SA levels and resistance to FHB.To further study SA synthesis pathways in wheat and avoid interference with pathogenicity related genes,the leaves of wild-type Cadenza and different TaICS mutant lines were subjected to ultraviolet treatment for transcriptomic analysis.The results showed that 37 PALs might be involved in endogenous SA synthesis,and 82 WRKY and MYB family transcription factors may regulate the expression of ICS and PAL.These results were further confirmed by RT-PCR.In conclusion,this study expands our knowledge of SA biosynthesis and identifies TaICSA,as well as several additional candidate genes that encode transcription factors for regulating endogenous SA levels,as part of an efficient strategy for enhancing FHB resistance in wheat.

OsbZIP53 Negatively Regulates Immunity Response by Involving in Reactive Oxygen Species and Salicylic Acid Metabolism in Rice

The basic region/leucine zipper(bZIP)transcription factors play important roles in plant development and responses to abiotic and biotic stresses.OsbZIP53 regulates resistance to Magnaporthe oryzae in rice by analyzing APIP5-RNAi transgenic plants.To further investigate the biological functions of OsbZIP53,we generated osbzip53 mutants using CRISPR/Cas9 editing and also constructed OsbZIP53 over-expression transgenic plants.Comprehensive analysis of phenotypical,physiological,and transcriptional data showed that knocking-out OsbZIP53 not only improved disease resistance by inducing a hypersensitivity response in plants,but also regulated the immune response through the salicylic acid pathway.Specifically,disrupting OsbZIP53 increased H2O2 accumulation by promoting reactive oxygen species generation through up-regulation of several respiratory burst oxidase homologs(Osrboh genes)and weakened H2O2 degradation by directly targeting OsMYBS1.In addition,the growth of osbzip53 mutants was seriously impaired,while OsbZIP53 over-expression lines displayed a similar phenotype to the wild type,suggesting that OsbZIP53 has a balancing effect on rice immune response and growth.

FaSnRK1a mediates salicylic acid pathways to enhance strawberry resistance to Botrytis cinerea

Strawberry is a major fruit crop worldwide because its nutritional and health benefits to human health,but its productivity is limited by Botrytis cinerea.Sucrose nonfermentation 1-related protein kinase 1(SnRK1)has a defense function against pathogens,but the function of SnRK1 in the defense response to B.cinerea in plants is still unclear.In this study,FaSnRK1a-OE and RNAi fruits were constructed and then inoculated with B.cinerea.The result reveals a positive role of Fa SnRK1a in the regulation of resistance to gray mold.FaSnRK1a affects SA content by regulating FaPAL1 and FaPAL2 expressions.The genes related to the SA signaling pathway(FaTGA1 and FaTGA2.1)were significantly increased/decreased in FaSnRK1a-OE or FaSnRK1a-RNAi fruit,respectively.FaSnRK1a interacted with the FaWRKY33.2 protein and negatively regulated FaWRKY33.2 expression,and FaWRKY33.2 acts as a repressor of disease resistance to B.cinerea.Finally,FaSnRK1a regulates the expression of six PR genes and the activities of antioxidant enzymes to boost defense response after B.cinerea inoculation.Our findings showed that FaSnRK1a increases the resistance of strawberry fruit to B.cinerea via SA signaling pathway and interaction with the FaWRKY33.2 transcription factor.

二维聚合物[MnNa(Salicylate)_2(CH_3OH)(H_2O)]_n·0.5nH_2O的合成、晶体结构与活性研究

In this paper, a novel polymeric complex [MnNa（Salicylate）2（CH3OH）（H2O）]n·0.5nH2O was obtained and characterized by IR spectra, elemental analysis and single crystal X-ray diffraction. The titled complex is crystallized in triclinic system, space group P1 with a=0.763 82（15） nm, b= 1.037 1（2） nm, c=1.290 9（3） nm, α= 103.59（3）°, β=104.65（3）°, γ=109.50（3）°, V=0.873 6（3） nm 3, Z=2, Dc=1.556 Mg/m 3, Mr=409.20, μ=0.823 mm -1, F（000）=418, R=0.0614, wR= 0.147 6. The activity in catalyzing the superoxygen anionic free radical dismutation was determinated.

Nitric Oxide Production is Involved in Inhibition Growth of Salicylate at Chilling Temperature

[Objective] The aim was to investigate whether NO is involved in the inhibitory effect of salicylic acid on the growth at low temperature in Arabidopsis.[Method] The endogenous NO level in roots of wild-type and NahG mutant growing at 22 or 4 ℃ was measured with NO-specific probe DAF-FM DA staining method.[Result] NO level in plants growing at 4 ℃ for a long term could be increased with time;low temperature could induce NO production in wild-type and NahG mutant,and the NO level in NahG mutant with low level of salicylic acid was significantly lower than that in wild-type.[Conclusion] NO was involved in the inhibitory effect of salicylic acid on the growth of Arabidopsis at low temperature.

Advances in Molecular Mechanism of Microbiological Degradation of Salicylate

Salicylate is a type of pollutant widely and persistently existed in environ- ment. Microbiological degradation of salicylate as one kind of biological remediation methods has the advantages of low cost, good effect and no secondary pollution, and also attracts wide attention both at home and abroad. Currently, many salicy- late-degrading bacteria are isolated and screened, while the molecular mechanism of salicylate metabolism is also worth deep research. The research about molecular mechanism of microorganism degradation was overviewed, various degrading path- ways including catechol meta-cleavage pathway and gentisate pathway were intro- duced, and the latest progress in regulating genes of salicylate degradation was summarized.

Effect of sodium salicylate on oxidative stress and insulin resistance induced by free fatty acids

BACKGROUND: It has been reported that high-dose salicylates improve free fatty acids (FFAs)-induced insulin resistance and beta-cell dysfunction in vitro, but the mechanism remains uncertain. In insulin-resistant rats, we found that the supplementation of sodium salicylate is associated with a reduction of plasma malondialdehyde (MDA), a marker of oxidative stress. Few studies have investigated the effects of salicylates on oxidative stress levels in insulin-resistant animal models. This study aimed to assess the effect of sodium salicylate on insulin sensitivity and to explore the potential mechanism by which it improves hepatic and peripheral insulin resistance. METHODS: Intralipid+heparin (IH), saline (SAL), or intralipid+heparin+sodium salicylate (IHS) were separately infused for 7 hours in normal Wistar rats. During the last 2 hours of the infusion, hyperinsulinemic-euglycemic clamping was 3 performed with [6-(3)H] glucose tracer. Plasma glucose was measured using the glucose oxygenase method. Plasma insulin and C-peptide were determined by radioimmunoassay. MDA levels and glutathione peroxidase (GSH-PX) activity in the liver and skeletal muscle were measured with colorimetric kits. RESULTS: Compared with infusion of SAL, IH infusion increased hepatic glucose production (HGP), and decreased glucose utilization (GU) (P<0.05). The elevation of plasma free fatty acids increased the MDA levels and decreased the GSH-PX activity in the liver and muscle (P<0.01). Sodium salicylate treatment decreased HGP, elevated GU (P<0.05), reduced MDA content by 60% (P<0.01), and increased the GSH-PX activity by 35% (P<0.05). CONCLUSIONS: Short-term elevation of fatty acids induces insulin resistance by enhancing oxidative stress levels in the liver and muscle. The administration of the anti-inflammatory drug sodium salicylate reduces the degree of oxidative stress, therefore improving hepatic and peripheral insulin resistance. IKK-beta and NF-kappa B provide potential pathogenic links to oxidative stress.

Effects of Sodium Salicylate on the Expression of HSP27 Protein during Oxidative Stress in Tissue-cultured Human Lens Epithelial Cells

The effects of sodium salicylate on the expression of heat shock protein 27 （HSP27） during oxidative stress in tissue-cultured human lens epithelial cells were investigated. Cultured human lens epithelial cells （HLB-3） were divided into 3 groups： control group （group A）, oxidation injury group （group B） and sodium salicylate group （group C）. Apoptosis of human lens epithelial cells cultured in vitro was induced in the presence of 150 μmol/L H2O2. Cells viability and the expression of HSP27 were analyzed. Viability of the cells was measured by methyl thiazole tetrazolium （MTT） chromatometry. The expression of HSP27 in HLB-3 cells was detected by using immunohistochemistry and image analysis system, Sodium salicylate could induce the expression of HSP27, and the cells viability in group C was significantly higher than in group B （0.2667±0.01414 vs 0.2150±0.01080, P=0.012〈0.05）. The average gray value of HSP27 in group B was less than that in group C （P=0.000〈0.05）. The increased expression of HSP27 by sodium salicylate might play an important role in the protection of hydrogen peroxide-induced injury of human lens epithelial cells, suggesting that sodium salicylate could suppress, at least in part, the apoptosis of human lens epithelial cells.

Kinetics of the Thermal Decomposition of Magnesium Salicylate Powder in Air

Simultaneous thermogravimetry-differential thermal analysis （TG-DTA） was used to study the kinetics and the degradation of magnesium salicylate（ C14H10MgO6 ） in air. The results show that the decomposition proceeds through two steps. The kinetics of the first decomposition step was studied. The activation energies were calculated by using the Friedman and Flynn Wall Ozawa（FWO） methods, and the most probable kinetic model function was estimated using the multiple linear regression method. The values of the correlated kinetic parameters for the first decomposition step are E = 152.97 kJ/mol, lg（A/S^-1 ） = 10. 78, f（α） = （ 1 - α）^n（ 1 ＋Kcatα）, n =0. 691, and Kcat = 1. 3048.

Measurement and Correlation of Solid-Liquid Equilibria of Phenyl Salicylate with C4 Alcohols

In an equilibrium vessel,the solid-liquid equilibria(SLE) for three binary mixtures of phenyl salicylate with 1-butanol,2-butanol,and 2-methyl-1-propanol,respectively,have been measured from 283.15 K to the melting temperature of the solute using a method in which an excess amount of solute was equilibrated with the alcohol solution.The liquid concentrations of the investigated phenyl salicylate in the saturated solution were analyzed by UV spectrometry.Activity coefficients for phenyl salicylate have been calculated by means of the Wilson,NRTL,and UNIQUAC equations and with them were correlated solubility data that were compared with the experimental ones.The best correlation of the solubility data has been obtained by the Wilson equation by which the average root-mean-square deviation of temperature for the three systems is 1.03 K.

Effects of Mitogen-activated Protein Kinase Signal Pathway on Heat Shock Protein 27 Expression in Human Lens Epithelial Cells Exposed to Sodium Salicylate in vitro

The roles of mitogen-activated protein kinase （MAPK） signal pathway in sodium salieylate-induced expression of heat shock protein 27 （HSP27） in human lens epithelial cells （HLECs-B3） in vitro were investigated. HLECs-B3 were incubated in the fresh media containing sodium salicylate at different concentrations for different durations, and allowed to be recovered in fresh medium without sodium salicylate for different durations with or without pretreatment with p38MAPK inhibitor （SB203580）, ERK1/2 inhibitor （PD98059） and JNK/SAPK inhibitor （SP600125）. The expression of P38MAPK, ERK1/2, JNK/SAPK, phosphorylated P38MAPK, phosphorylated ERK1/2, phosphorylated JNK/SAPK and HSP27 was detected by Western blot. The expression of HSP27 mRNA and protein was detected by RT-PCR and immunohistochemistry respectively. It was found there was only weak expression of HSP27 in normal HLECs. The expression of HSP27 was not detectable in HLECs-B3 that were exposed to sodium salicylate （55 retool/L） for 1-5 h. It was indicated that recovery from sodium salicylate （〉35 mmol/L） significantly increased the synthesis of HSP27. The expression of HSP27 was up-regulated in HLECs-B3 under sodium salicylate recovery for 3 h, reached the peak level for 6 h, and returned to the level of control cells by 24 h. Activation of P38MAPK from sodium salicylate stimulation occurred at 30th rain, and increased significantly at 1st h, then declined and renamed to baseline level at 3rd h under sodium salicylate recovery. Activation of ERK1/2 occurred at 1st h and reached the peak level at 6th h under sodium salicylate recovery. However, JNK/SAPK was inactivated by sodium salicylate. The expression of HSP27 could be down-regulated with the pretreatment of SB203580 and PD98059 jointly. It is concluded that sodium salicylate can induce the expression of HSP27 in HLECs-B3. The effects are mediated, at least in part, through the activation of P38MAPK and ERK1/2 signaling pathway.

THE EFFECTS OF SALICYLATE ON AUDITORY EVOKED POTENTIAL AMPLITWDE FROM THE AUDITORY CORTEX AND AUDITORY BRAINSTEM

Tinnitus has often been studied using salicylate in animal models as they are capable of inducing tempo-rary hearing loss and tinnitus. Studies have recently observed enhancement of auditory evoked responses of the auditory cortex (AC) post salicylate treatment which is also shown to be related to tinnitus like behavior in rats. The aim of this study was to observe if enhancements of the AC post salicylate treatment are also present at structures in the brainstem. Four male Sprague Dawley rats with AC implanted electrodes were tested for both AC and auditory brainstem response (ABR) recordings pre and post 250 mg/kg intraperitone-al injections of salicylate. The responses were recorded as the peak to trough amplitudes of P1-N1 (AC), ABR wave V, and ABR waveⅡ. AC responses resulted in statistically significant enhancement of ampli-tude at 2 hours post salicylate with 90 dB stimuli tone bursts of 4, 8, 12, and 20 kHz. Wave V of ABR re-sponses at 90 dB resulted in a statistically significant reduction of amplitude 2 hours post salicylate and a mean decrease of amplitude of 31%for 16 kHz. WaveⅡamplitudes at 2 hours post treatment were signifi-cantly reduced for 4, 12, and 20 kHz stimuli at 90 dB SPL. Our results suggest that the enhancement chang-es of the AC related to salicylate induced tinnitus are generated superior to the level of the inferior colliculus and may originate in the AC.

Salicylate enhances expression and function of NMDA receptors in cochlear spiral ganglion neurons

Objective To study the effect of salicylate on the expression and function of NMDA receptors in spiral ganglion neurons （SGNs）. Methods The mRNA of NR1 subunit of NMDA receptor in modiolus tissues were detected by Real time fluorescence quantitative PCR （FQ-PCR）. NMDA receptor whole-cell currents were recorded using patch clamp in acute isolated SGNs. Results Compared with the control group, salicylate significantly increased the mRNA level of NR1 subunit in SGNs. NMDA of concentrations ranging from 0.1 mM to 10 mM evoked no current in SGNs. NMDA （0. 1mM and 0.5 mM） applied with salicylate （5 mM）, however, induced inward currents （212.6±15.2pA, n=5; 607.9±44.3pA, n=5） in a dose-dependent manner, which could be inhibited by APV. Salicylate alone did not produce any current in SGNs. Conclusion Salicylate increases the expression of NMDA receptors and facilitates the currents mediated by NMDA receptors in SGNs.

Synthesis and Crystal Structure of the Ladder-like Organotin Complex: μ-pentaoxygen bridged penta(bis-benzyltin) bis-salicylate

A novel organotin complex of μ-pentaoxygen bridged penta（bis-benzyltin） bissalicylate has been synthesized by the reaction of bis-benzyltin oxide and salicylic acid and its structure has been determined by X-ray diffraction. The crystal belongs to monoclinic, space group P21/n with a = 1.7206（5）, b = 2.1401（6）, c = 2.1488（6）nm, β= 93.325（5）°, V = 7.899（4） nm^3, Z = 4, Dc = 1.564 g/cm^3,μ（MoKα） = 16.17cm^-1, Mr = 1859.94, F（000） = 3692, R1= 0.0755 and wR2= 0.1557. According to structural analysis, the coordination geometry of tin is a distorted trigonal bipyramid, and the ladder-like structure is shaped by four Sn2O2 planar four-membered rings.

X-ray absorption study of tribofilms from ZDDP and overbased salicylate detergents

The interaction of overbased salicylate detergents with zinc dialkyldithiophosphates （ZDDP） and its effect on the formation of tribofilms under boundary lubrication have been studied by means of X-ray absorption near-edge structure spectroscopy. The results show that addition of metallic detergents to neat ZDDP results in the change of surface chemistry of the tribofilm formed from neat ZDDP. Calcium from detergents is digested in the tribofilm. For the high overbased detergents, the deposit of overbasing agent CaCO3 in the tribofilm is also observed along with the formation of calcium phosphate in tribofilms.

Multiform Host Lattices in the Layer Type Inclusion Compound of Thiourea with Tetrabutylammonium Salicylate and Water

A new inclusion complex thiourea with tetrabutylammonium salicylate and water, 4(C4H9)4N+C7H5O3 ?4(NH2)2CS?2H2O, has been prepared and characterized by X-ray crystallo- graphy. Crystal data: MoKα radiation, triclinic, space group P1 with a = 13.505(5), b = 13.645(5), c = 30.720(10) ?, α = 92.872(7), β = 92.329(7), γ = 92.538(7)°, V = 5643.0(3) ?3, C96H184N12O14S4, Mr = 1858.79, Z = 2, Dc = 1.094 g/cm3, μ = 0.143 mm-1, F(000) = 2040, R = 0.0694 and wR = 0.1282 for 4303 observed reflections with I > 2σ(I). There are three different layer type host-lattices in the crystal structure of the title compound. All of them are formed by [(NH2)2CS·(C7H5O3 )]4 tetramers, but water molecules are located between tetramers and link them by hydrogen bonds to generate ribbons at c = 0 and 1/2, and isolated tetramers are arranged side by side at c = 1/4. The tetrabutylammonium cations are sandwiched between puckered layers.

A Meta-analysis of Salicylates for Type 2 Diabetes Mellitus

The aim of this study was to assess the effects and safety of salicylates on type 2 diabetes mellitus （T2DM）. We searched six databases （Cochrane Central Register of Controlled Trials, MED- LINE, EMBASE, CBM, CNKI and VIP） for all randomized controlled trials （RCTs） and self-control studies which investigated the effects of salicylates on T2DM. We included 34 RCTs and 17 self-control studies involving 13 464 patients with T2DM. It was demonstrated that salicylates had obvious effects on several parameters for patients with T2DM. （1） Any dose of salicylates could significantly reduce HbAIc level [mean difference （MD） -0.39%; 95% C1-0.47 to -0.32] in RCTs, but only high doses of salicylates （〉3000 mg/day） could effectively reduce fasting plasma glucose （FPG） level [standardized mean difference （SMD） -1.05; 95% CI -1.47 to -0.62] for patients with T2DM in both RCTs and self-control studies. Furthermore, high doses of salicylates could also increase plasma fasting insulin level （MD 12.20 mU/L; 95% CI 3.33 to 21.07）; （2） In both RCTs and self-control studies, high doses of salicylates could significantly reduce plasma triglycerides concentration. The results for RCTs were MD -0.44 mmol/L, 95% CI -0.71 to 4）.18, and those for self-control studies were 227±29 mg/dL （pre-treatment） and 117±8 mg/dL （post-treatment） （P=-0.009）; （3） All trials which reported cardiovascu- lar events were RCTs using low doses （〈1000 mg/day） of salicylates, and it was revealed that aspirin could significantly reduce the risk of myocardial infarction （OR 0.73; 95% CI 0.57 to 0.92）; （4） Two RCTs and two self-control studies with 〉3000 mg/day salicylates reported adverse effects, and the over- all effects were mild, and tinnitus occurred most frequently. No evidence of gastrointestinal bleeding was found in all these studies. In conclusion, from our systematic review, the anti-diabetic effect of salicylates is in a dose-dependent manner. High doses of salicylates may have beneficial effects on re- ducing FPG, HbAlc level and increasing fasting insulin concentration, and may also have some positive effects on lipidemia and inflammation-associated parameters for patients with T2DM, without serious adverse effects.

Syntheses and Structures of Two Novel Salicylate-containing Mononuclear Manganese Complexes

Two salicylate containing mononuclear manganese complexes formulated as [Mnand characterized by elemental analysis, IR and single-crystal X-ray diffraction analyses. Crystal data for compound 1： monoclinic, space group C2/c, a=30.748（6）, b=8.1933（13）, c=21.137（4） A, β=126.772（4）°, V=4265.5（13）A^3, Z=8, Mr=471.34, Dc=1.468 g/cm^3, μ=0.667 mm^-1, F（000）=1952,the final R=0.0637, wR=0.1783 （I 〉 2σ（I）） and GOOF=1.073; and those for compound 2： monoclinic,space group C2/c, a=14.505（5）, b=11.048（4）, c=20.711 （7）（A）, β=103.603（6）°, V=3225.6 （18）A^3, Z=4, Mr=668.65, Dc=1.377 g/cm^3, μ=0.466 mm^-1, F（000）=1416, the final R=0.0373, wR=0.1125 （I 〉2σ（I））, and GOOF=1.000. The Mn atoms of both complexes are six-coordinated in an axially elongated octahedral geometry for 1 and an axially compressed octahedral geometry for 2, and their oxidation states have been determined to be trivalent by bond valence sum calculation.