Modulation of histone acetylation enables fully mechanized hybrid rice breeding.

Hybrid rice has achieved high grain yield and greatly contributes to food security, but the manual-labour-intensive hybrid seed production process limits fully mechanized hybrid rice breeding. For next-generation hybrid seed production, the use of small-grain male sterile lines to mechanically separate small hybrid seeds from mixed harvest is promising. However, it is difficult to find ideal grain-size genes for breeding ideal small-grain male sterile lines without penalties in the number of hybrid seeds and hybrid rice yield. Here we report that the use of small-grain alleles of the ideal grain-size gene GSE3 in male sterile lines enables fully mechanized hybrid seed production and dramatically increases hybrid seed number in three-line and two-line hybrid rice systems. The GSE3 gene encodes a histone acetyltransferase that binds histones and influences histone acetylation levels. GSE3 is recruited by the transcription factor GS2 to the promoters of their co-regulated grain-size genes and influences the histone acetylation status of their co-regulated genes. Field trials demonstrate that genome editing of GSE3 can be used to immediately improve current elite male sterile lines of hybrid rice for fully mechanized hybrid rice breeding, providing a new perspective for mechanized hybrid breeding in other crops.

Nudifloside, a Secoiridoid Glucoside Derived from Callicarpa nudiflora, Inhibits Endothelial-to-Mesenchymal Transition and Angiogenesis in Endothelial Cells by Suppressing Ezrin Phosphorylation.

Callicarpa nudiflora is a traditional folk medicine in China used for eliminating stasis to subdue swelling. Several compounds from Callicarpa nudiflora have been proved to show anti-inflammatory, haemostasis, hepatitis, and anti-proliferative effects. Tumor endothelial cells play crucial roles in tumor-induced angiogenesis. Recently, it was demonstrated that ECs may be the important source of cancer associated fibroblasts (CAFs) through endothelial to mesenchymal transition (EndoMT). In this study, we evaluated the effects of nudifloside (NDF), a secoiridoid glucoside from Callicarpa Nudiflora, on TGF-ß1-induced EndoMT and VEGF-induced angiogenesis, and the underlying mechanisms were also involved. It was found that NDF significantly inhibited enhanced migration, invasion and F-actin assembly in endothelial cells (ECs) exposed in TGF-ß1. NDF obviously reversed expression of several biomarkers associated with EndoMT and recovered the morphological characteristics of ECs and tube-like structure induced by TGF-ß1. Furthermore, treatment of NDF resulted in a significant destruction of VEGF-induced angiogenesis in vitro and ex vivo. Data from co-immunoprecipitation assay provided the evidence that Ezrin phosphorylation and the interaction with binding protein can be inhibited by NDF, which can be confirmed by data from Ezrin silencing assay. Collectively, the application of NDF inhibited TGF-ß1-induced EndoMT and VEGF-induced angiogenesis in ECs by reducing Ezrin phosphorylation.

OsBCAT2, a gene responsible for the degradation of branched-chain amino acids, positively regulates salt tolerance by promoting the synthesis of vitamin B5.

Salt stress negatively affects rice growth, development and yield. Metabolic adjustments contribute to the adaptation of rice under salt stress. Branched-chain amino acids (BCAA) are three essential amino acids that cannot be synthesized by humans or animals. However, little is known about the role of BCAA in response to salt stress in plants. Here, we showed that BCAAs may function as scavengers of reactive oxygen species (ROS) to provide protection against damage caused by salinity. We determined that branched-chain aminotransferase 2 (OsBCAT2), a protein responsible for the degradation of BCAA, positively regulates salt tolerance. Salt significantly induces the expression of OsBCAT2 rather than BCAA synthesis genes, which indicated that salt mainly promotes BCAA degradation and not de novo synthesis. Metabolomics analysis revealed that vitamin B5 (VB5) biosynthesis pathway intermediates were higher in the OsBCAT2-overexpressing plants but lower in osbcat2 mutants under salt stress. The salt stress-sensitive phenotypes of the osbcat2 mutants are rescued by exogenous VB5, indicating that OsBCAT2 affects rice salt tolerance by regulating VB5 synthesis. Our work provides new insights into the enzymes involved in BCAAs degradation and VB5 biosynthesis and sheds light on the molecular mechanism of BCAAs in response to salt stress.

OsMDH12: A Peroxisomal Malate Dehydrogenase Regulating Tiller Number and Salt Tolerance in Rice.

Salinity is an important environmental factor influencing crop growth and yield. Malate dehydrogenase (MDH) catalyses the reversible conversion of oxaloacetate (OAA) to malate. While many MDHs have been identified in various plants, the biochemical function of MDH in rice remains uncharacterised, and its role in growth and salt stress response is largely unexplored. In this study, the biochemical function of OsMDH12 was determined, revealing its involvement in regulating tiller number and salt tolerance in rice. OsMDH12 localises in the peroxisome and is expressed across various organs. In vitro analysis confirmed that OsMDH12 converts OAA to malate. Seedlings of OsMDH12-overexpressing (OE) plants had shorter shoot lengths and lower fresh weights than wild-type (WT) plants, while osmdh12 mutants displayed the opposite. At maturity, OsMDH12-OE plants had fewer tillers than WT, whereas osmdh12 mutants had more, suggesting OsMDH12's role in tiller number regulation. Moreover, OsMDH12-OE plants were sensitive to salt stress, but osmdh12 mutants showed enhanced salt tolerance. The Na+/K+ content ratio increased in OsMDH12-OE plants and decreased in osmdh12 mutants, suggesting that OsMDH12 might negatively affect salt tolerance through influencing the Na+/K+ balance. These findings hint at OsMDH12's potential as a genetic tool to enhance rice growth and salt tolerance.

Comprehensive DNA methylation profiling of COVID-19 and hepatocellular carcinoma to identify common pathogenesis and potential therapeutic targets.

BACKGROUND & AIMS: The effects of SARS-CoV-2 infection can be more complex and severe in patients with hepatocellular carcinoma (HCC) as compared to other cancers. This is due to several factors, including pre-existing conditions such as viral hepatitis and cirrhosis, which are commonly associated with HCC. METHODS: We conducted an analysis of epigenomics in SARS-CoV-2 infection and HCC patients, and identified common pathogenic mechanisms using weighted gene co-expression network analysis (WGCNA) and other analyses. Hub genes were identified and analyzed using LASSO regression. Additionally, drug candidates and their binding modes to key macromolecular targets of COVID-19 were identified using molecular docking. RESULTS: The epigenomic analysis of the relationship between SARS-CoV-2 infection and HCC patients revealed that the co-pathogenesis was closely linked to immune response, particularly T cell differentiation, regulation of T cell activation and monocyte differentiation. Further analysis indicated that CD4+ T cells and monocytes play essential roles in the immunoreaction triggered by both conditions. The expression levels of hub genes MYLK2, FAM83D, STC2, CCDC112, EPHX4 and MMP1 were strongly correlated with SARS-CoV-2 infection and the prognosis of HCC patients. In our study, mefloquine and thioridazine were identified as potential therapeutic agents for COVID-19 in combined with HCC. CONCLUSIONS: In this research, we conducted an epigenomics analysis to identify common pathogenetic processes between SARS-CoV-2 infection and HCC patients, providing new insights into the pathogenesis and treatment of HCC patients infected with SARS-CoV-2.

Molecular mechanism of Ganji Fang in the treatment of hepatocellular carcinoma based on network pharmacology, molecular docking and experimental verification technology.

Background: Hepatocellular carcinoma (HCC) is a malignant tumor harmful to human health. Ganji Fang (GJF) has good clinical efficacy in the treatment of HCC, but its mechanism is still unclear. Objective: The aim of this study was to investigate the mechanism of action of GJF in the treatment of HCC through network pharmacology, molecular docking and in vitro experiments. Methods: A series of network pharmacology methods were used to identify the potential targets and key pathways of GJF in the treatment of HCC. Then, molecular docking technology was used to explore the binding ability of key active ingredients and targets in GJF. Multiple external databases were used to validate the key targets. In in vitro experiments, we performed MTT assays, wound-healing assays, cell cycle assays, apoptosis assays and RT‒qPCR to verify the inhibitory effect of GJF on the Human hepatoma G2 (HepG2) cells. Result: A total of 162 bioactive components and 826 protein targets of GJF were screened, and 611 potential targets of HCC were identified. Finally, 63 possible targets of GJF acting on HCC were obtained. KEGG enrichment analyses showed that the top five pathways were the cell cycle, cellular senescence, p53 signaling pathway, PI3K/Akt signaling pathway, and progesterone-mediated oocyte maturation. Among them, we verified the PI3K/Akt signaling pathway. CCNE1, PKN1, CCND2, CDK4, EPHA2, FGFR3, CDK6, CDK2 and HSP90AAI were enriched in the PI3K/Akt pathway. The molecular docking results showed that the docking scores of eight active components of GJF with the two targets were all less than -5.0, indicating that they had certain binding activity. In vitro cell experiments showed that GJF could inhibit the proliferation and migration of HepG2 cells, block the cell cycle and induce apoptosis of HepG2 cells, which may be related to the PI3K/Akt signaling pathway. In summary, EPHA2 may be an important target of GJF in HCC, and pachymic acid may be an important critical active compound of GJF that exerts anticancer activity. Conclusion: In general, we demonstrated, for the first time, that the molecular mechanism of GJF in HCC may involve induction of G0/G1 phase cycle arrest through inhibition of the PI3K/Akt signaling pathway and promote apoptosis of hepatoma cell lines. This study provides a scientific basis for the subsequent clinical application of GJF and the in-depth study of its mechanism.

Recent Advances in Development of Metal-Organic Frameworks Based Extraction Approaches for Food and Biological Matrices.

Food and human biological samples analysis are of great importance for human health. However, due to the complexity of sample matrices and low concentrations of target analytes, sample preparation is essentially critical for these samples through the whole analytical workflow. Metal-organic frameworks (MOFs), a class of synthesized functional nanomaterial, have been well recognized as novel adsorbents to enhance the sensitivity of current analytical methods and greatly assist the determination of potentially harmful substances present in food and biological samples. This critical review summarized the most advances in the applications of MOFs or hybrid MOFs as adsorbents for food and biological analysis in the past five years, particularly pertaining to sample preparation purpose including removal, adsorption, and enrichment of environmental contaminants. The synthetic routes and analytical performance of representative MOFs or MOFs composites are discussed. The limitations in preparation and application of reported MOFs adsorbents are discussed and the improvement methods for these limitations also have been concluded in the future perspectives.

Natural variations of OsAUX5, a target gene of OsWRKY78, control the neutral essential amino acid content in rice grains.

Grain essential amino acid (EAA) levels contribute to rice nutritional quality. However, the molecular mechanisms underlying EAA accumulation and natural variation in rice grains remain unclear. Here we report the identification of a previously unrecognized auxin influx carrier subfamily gene, OsAUX5, which encodes an amino acid transporter that functions in uptake of multiple amino acids. We identified an elite haplotype of Pro::OsAUX5Hap2 that enhances grain EAA accumulation without an apparent negative effect on agronomic traits. Natural variations of OsAUX5 occur in the cis elements of its promoter, which are differentially activated because of the different binding affinity between OsWRKY78 and the W-box, contributing to grain EAA variation among rice varieties. The two distinct haplotypes were shown to have originated from different Oryza rufipogon progenitors, which contributed to the divergence between japonica and indica. Introduction of the indica-type Pro::OsAUX5Hap2 genotype into japonica could significantly increase EAA levels, indicating that indica-type Pro::OsAUX5Hap2 can be utilized to increase grain EAAs of japonica varieties. Collectively, our study uncovers an WRKY78-OsAUX5-based regulatory mechanism controlling grain EAA accumulation and provides a potential target for breeding EAA-rich rice.

Ultra-high-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry coupled with three-step data post-processing techniques for comprehensive profiling of the multiple components in Fufang Xianzhuli Ye.

INTRODUCTION: Fufang Xianzhuli (FXZL) Ye, a classical formula of traditional Chinese medicine, is composed of Succus Bambusae, Houttuyniae herba, Pinelliae Rhizoma, Zingiberis Rhizoma Recens, Eriobotryae Folium, Platycodonis Radix, and peppermint oil. For many years, FXZL has been primarily utilised in China to treat cough and phlegm. The chemical composition of FXZL has not been reported, which seriously affects the safety of the clinical application. OBJECTIVE: To establish a systematic method for rapidly classifying and recognising the chemical constituents in the FXZL for the safety of the clinical application. METHODS: An ultra-high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry coupled with a three-step data post-processing strategy was developed to screen the chemical constituents of FXZL. RESULTS: In this experiment, the diagnostic ions in FXZL were classified into six main compounds. A total of 106 compounds were unambiguously identified in FXZL based on their retention times, accurate masses, and tandem mass spectrometry data. These include 11 chlorogenic acids, three flavonoids, eight sesquiterpenoids, six organic acids, 65 triterpenoid saponins, and 13 other compounds. CONCLUSION: The chemical composition of FXZL was identified and summarised, providing useful information for quality control and a basis for further exploration of its active ingredients in vivo.

Cucurbit(n)uril-functionalized magnetic composite for the dispersive solid-phase extraction of perfluoroalkyl and polyfluoroalkyl substances in environmental samples with determination by ultra-high performance liquid chromatography coupled to Orbitrap high-resolution mass spectrometry.

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) have raised serious public health concerns because of their potential adverse effects in humans as revealed by toxicological and epidemiological research. However, routine monitoring of PFASs is still challenging due to their trace levels in various environmental and biological matrices. In this study, magnetic composite materials based on iron (II, III) oxide (Fe3O4) with surface functionalization by cucurbit(n)uril (CB(n)) (Fe3O4@CB(n)) (n = 6, 7, 8), were prepared and evaluated as new adsorbents for the magnetic solid-phase extraction of nine PFASs in lake water, tap water and fish muscle samples. The Fe3O4@CB(n) was characterized to examine their surface morphologies, sizes magnetism and thermal stability. Featuring good aqueous solution dispersibility, the macrocyclic structure of Fe3O4@CB(n) was also endowed with strong host-guest interactions, allowing extraction and enrichment capability towards the PFASs in complex matrices. MSPE using Fe3O4@CB(7) combination with ultra-high performance liquid chromatography coupled to Orbitrap high-resolution mass spectrometry, gave satisfactory quantitative analytical performance with low limits of detection of 0.004-0.04 µg L-1 and limits of quantification of 0.005-0.1 µg L-1, linearities ranging from 0.01 to 10 µg L-1 with high coefficients of determination (R2 ≥ 0.993), and enrichment factors (15-76) for the nine target PFASs. The method proved to be effective for the enrichment and analysis of trace levels of PFASs in genuine environmental water and fish muscle samples, indicating that Fe3O4@CB(7) has promising applicability as an adsorbent for these contaminants.

Nucleophilic Dearomatization Strategy to Synthesize Disubstituted 3-Isoquinolinones under Transition Metal-Free Conditions.

Herein, a one-pot protocol for constructing the disubstituted isoquinolinone derivatives via the three-component reactions of 3-haloisoquinolines, alkyl halides, and indoles under transition-metal-free conditions is described. The reaction realized the trifunctionalization of isoquinoline via a dearomatization strategy, which displayed high chemical selectivity, excellent functional group tolerance, and a wide range of substrates, and is environmentally friendly. The three-component coupling involves the construction of new C-N, C═O, and C-C bonds in one step.

A natural allele of OsMS1 responds to temperature changes and confers thermosensitive genic male sterility.

Changes in ambient temperature influence crop fertility and production. Understanding of how crops sense and respond to temperature is thus crucial for sustainable agriculture. The thermosensitive genic male-sterile (TGMS) lines are widely used for hybrid rice breeding and also provide a good system to investigate the mechanisms underlying temperature sensing and responses in crops. Here, we show that OsMS1 is a histone binding protein, and its natural allele OsMS1wenmin1 confers thermosensitive male sterility in rice. OsMS1 is primarily localized in nuclei, while OsMS1wenmin1 is localized in nuclei and cytoplasm. Temperature regulates the abundances of OsMS1 and OsMS1wenmin1 proteins. The high temperature causes more reduction of OsMS1wenmin1 than OsMS1 in nuclei. OsMS1 associates with the transcription factor TDR to regulate expression of downstream genes in a temperature-dependent manner. Thus, our findings uncover a thermosensitive mechanism that could be useful for hybrid crop breeding.

OsbZIP18, a Positive Regulator of Serotonin Biosynthesis, Negatively Controls the UV-B Tolerance in Rice.

Serotonin (5-hydroxytryptamine) plays an important role in many developmental processes and biotic/abiotic stress responses in plants. Although serotonin biosynthetic pathways in plants have been uncovered, knowledge of the mechanisms of serotonin accumulation is still limited, and no regulators have been identified to date. Here, we identified the basic leucine zipper transcription factor OsbZIP18 as a positive regulator of serotonin biosynthesis in rice. Overexpression of OsbZIP18 strongly induced the levels of serotonin and its early precursors (tryptophan and tryptamine), resulting in stunted growth and dark-brown phenotypes. A function analysis showed that OsbZIP18 activated serotonin biosynthesis genes (including tryptophan decarboxylase 1 (OsTDC1), tryptophan decarboxylase 3 (OsTDC3), and tryptamine 5-hydroxylase (OsT5H)) by directly binding to the ACE-containing or G-box cis-elements in their promoters. Furthermore, we demonstrated that OsbZIP18 is induced by UV-B stress, and experiments using UV-B radiation showed that transgenic plants overexpressing OsbZIP18 exhibited UV-B stress-sensitive phenotypes. Besides, exogenous serotonin significantly exacerbates UV-B stress of OsbZIP18_OE plants, suggesting that the excessive accumulation of serotonin may be responsible for the sensitivity of OsbZIP18_OE plants to UV-B stress. Overall, we identified a positive regulator of serotonin biosynthesis and demonstrated that UV-B-stress induced serotonin accumulation, partly in an OsbZIP18-dependent manner.

Comprehensive analysis of ESR1-related ceRNA axis as a novel prognostic biomarker in hepatocellular carcinoma.

Aims: To further understand, detect and treat hepatocellular carcinoma (HCC), it is urgent to conduct more in-depth research on the mechanism of sex-associated differences. Materials & methods: We established a ceRNA triple regulatory axis associated with ESR1 in HCC and performed expression, survival and nuclear-cytoplasmic localization analyses. In addition to this, we performed methylation analysis and immune infiltration analysis of the ceRNA axis. Results: We constructed the LINC01018/hsa-miR-197-3p/GNA14 (lncRNA/miRNA/mRNA) ceRNA axis to further explain the mechanism of sex-related prognosis in the development of HCC and to provide new insights into candidate biomarkers for targeted therapies. Conclusion: Our study is an innovative attempt at demonstrating the mechanism underlying the prognosis associated with sex differences in HCC by constructing a ceRNA axis (LINC01018/hsa-miR-197-3p/GNA14).

Association between maternal exposure to perfluoroalkyl and polyfluoroalkyl substances and risks of adverse pregnancy outcomes: A systematic review and meta-analysis.

Perfluoroalkyl and polyfluoroalkyl substances (PFASs), a class of persistent endocrine-disrupting chemicals, are widely used in consumer products due to their unique amphiphilic properties. Previous epidemiological studies suggest association of maternal PFASs exposure and adverse pregnancy outcomes, while evidences about the association are inconsistent. The aim of this systematic review and meta-analysis is to assess the relationship of maternal PFASs exposure and adverse pregnancy outcomes. Twenty-one relevant studies were identified from three databases before 2020. The quality, heterogeneity and possibility of publication bias of included studies were evaluated by Newcastle-Ottawa Scale, Q-statistic and Begg's test, respectively. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were obtained by means of random-effects meta-analysis models. Meta-analysis results revealed that maternal exposure to perfluorooctane sulfonic acid (PFOS) may have a positive association with preterm birth (OR = 1.20, 95% CI: 1.04, 1.38). The pooled estimates also showed limited evidence of association between maternal perfluorononanoic acid (PFNA) exposure and miscarriage (OR = 1.48, 95% CI: 0.92, 2.38) with obvious heterogeneity (I2 = 93.9, p < 0.01). However, no such significant associations were found between the other PFASs and miscarriage, stillbirth and preterm birth. In addition, the subgroup analyses showed that studies on the relationship of maternal PFASs exposure and miscarriage were mainly contributed by developed countries. The meta-analysis results indicated maternal exposure to PFOS can increase the risk of preterm birth. The results of the included studies are inconsistent and the effects of PFASs on human health are complex. Further studies with enough samples are required to verify these findings.

The LARGE2-APO1/APO2 regulatory module controls panicle size and grain number in rice.

Panicle size and grain number are important agronomic traits and influence grain yield in rice (Oryza sativa), but the molecular and genetic mechanisms underlying panicle size and grain number control remain largely unknown in crops. Here we report that LARGE2 encodes a HECT-domain E3 ubiquitin ligase OsUPL2 and regulates panicle size and grain number in rice. The loss of function large2 mutants produce large panicles with increased grain number, wide grains and leaves, and thick culms. LARGE2 regulates panicle size and grain number by repressing meristematic activity. LARGE2 is highly expressed in young panicles and grains. Biochemical analyses show that LARGE2 physically associates with ABERRANT PANICLE ORGANIZATION1 (APO1) and APO2, two positive regulators of panicle size and grain number, and modulates their stabilities. Genetic analyses support that LARGE2 functions with APO1 and APO2 in a common pathway to regulate panicle size and grain number. These findings reveal a novel genetic and molecular mechanism of the LARGE2-APO1/APO2 module-mediated control of panicle size and grain number in rice, suggesting that this module is a promising target for improving panicle size and grain number in crops.

Exposure to perfluoroalkyl substances and allergic outcomes in children: A systematic review and meta-analysis.

BACKGROUND: Perfluoroalkyl substances (PFASs) are persistent organic pollutants and widespread throughout the environment. Although exposure to PFASs may contribute to the development of allergic diseases in children, evidence about this association remains inconclusive. OBJECTIVE: To conduct a systematic review and meta-analysis to assess the association between PFASs exposure and allergic diseases in children based on current evidence. METHODS: The databases including PubMed, EMBASE, and Web of Science were searched to identify all observational studies that examined the association between PFASs exposure and the risk of childhood allergic diseases. The Newcastle-Ottawa Scale was used to evaluate the quality of case-crossover studies, and a previously validated quality assessment framework was used for observational studies lacking control groups. Random-effects meta-analysis models were applied to pool odds ratio (OR) with 95% confidence intervals (CIs). RESULTS: From an initial 94 articles (after duplicate removal), 13 studies through full-text assessment were included for quantitative assessment and descriptive synthesis. They are ten cohort studies, two cross-sectional studies, and one case-control study. The pooled estimates showed that perfluorononanoic acid (PFNA) was associated with eczema (OR = 0.89, 95% CI = 0.80-0.99), perfluorooctanesulfonic acid (PFOS) with atopic dermatitis (OR = 1.26, 95% CI = 1.01-1.58), and perfluorooctanoic acid (PFOA) with allergic rhinitis (OR = 1.33, 95% CI = 1.13-1.56). However, no such significant associations were found for wheeze and asthma. CONCLUSIONS: The meta-analysis results suggest that PFASs exposure could potentially be associated with eczema, atopic dermatitis, and allergic rhinitis during childhood, but not with childhood asthma or wheeze. Future studies are needed to verify these findings.

Two new iridoid glycosides from Callicarpa nudiflora.

Two new iridoid glycosides, callicoside E (1) and callicoside F (2), were isolated from the leaves of Callicarpa nudiflora. Their structures were established by one- and two-dimensional NMR spectroscopy and mass spectrometry. In an in vitro bioassay, compounds 1 and 2 showed an pronounced hepatoprotective activity against d-galactosamine-induced toxicity in WB-F344 rat hepatic epithelial stem-like cells.[Formula: see text].

Over-expression of a plasma membrane H+-ATPase SpAHA1 conferred salt tolerance to transgenic Arabidopsis.

The SpAHA1 gene, encoding a plasma membrane (PM) H+-ATPase (AHA) in Sesuvium portulacastrum, was transformed into Arabidopsis plants, and its expression increased salinity tolerance of transgenic Arabidopsis plants: seed germination ratio, root growth, and biomass of transgenic plants were greater compared to wild-type plants under NaCl treatment condition. Upon salinity stress, both Na+ and H+ effluxes in the roots of SpAHA1 expressing plants were faster than those of untransformed plants. Transformed plants with SpAHA1 had lower Na+ and higher K+ contents relative to wild-type plants when treated with NaCl, resulting in greater K+/Na+ ratio in transgenic plants than in wild-type plants under salt stress. Extent of oxidative stress increased in both transgenic and wild-type plants exposed to salinity stress, but overexpression of SpAHA1 could alleviate the accumulation of hydrogen peroxide (H2O2) induced by NaCl treatment in transgenic plants relative to wild-type plants; the content of malondialdehyde (MDA) was lower in transgenic plants than that in wild-type plants under salinity stress. These results suggest that the higher H+-pumping activity generated by SpAHA1 improved the growth of transgenic plants via regulating ion and reactive oxygen species (ROS) homeostasis in plant cells under salinity stress.

Inhibitory effects of luteolin­4'­O­ß­D­glucopyranoside on P2Y12 and thromboxane A2 receptor­mediated amplification of platelet activation in vitro.

Platelet activation and subsequent accumulation at sites of vascular injury are central to thrombus formation, which is considered to be a trigger of several cardiovascular diseases. Callicarpa nudiflora (C. nudiflora) Hook is a traditional Chinese medicinal herb for promoting blood circulation by removing blood stasis. In our previous study, several compounds extracted from this herb, including luteolin­4'­O­ß­D­glucopyranoside (LGP), were revealed to exert inhibitory effects on adenosine diphosphate (ADP)­induced platelet aggregation. The aim of present study was to confirm these antiplatelet effects and elucidate the potential mechanisms. Using a platelet­aggregation assay, it was revealed that LGP significantly inhibited platelet aggregation induced by ADP, U46619 and arachidonic acid. It was also found that LGP exhibited marked inhibitory effects on the activation of αIIbß3 integrin, the secretion of serotonin from granules, and the synthesis of thromboxane A2. In addition, the results showed that LGP suppressed Ras homolog family member A and phosphoinositide 3­kinase/Akt/glycogen synthase kinase 3ß signal transduction. Data from a radiolabeled ligand­binding assay indicated that LGP exhibited apparent competing effects on thromboxane receptor (TP) and P2Y12 receptors. In conclusion, the data presented here demonstrated that LGP, a natural compound from C. nudiflora Hook, inhibited the development of platelet aggregation and amplification of platelet activation. These inhibitory effects may be associated with its dual­receptor inhibition on P2Y12 and TP receptors.