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The biosynthesis of salvianolic acid B shares the phenylpropanoid pathway with lignin, and cinnamoyl CoA reductase (CCR; EC 1.2.1.44) is a specific enzyme in the lignin pathway. In this study, a CCR gene ( SmCCR1) from Salvia miltiorrhiza Bunge was cloned using DNA walking technology (GenBank ID: JF798634). The full-length SmCCR1 is 2,489 bp long and consists of four introns and five exons encoding a polypeptide of 324 amino acid residues. Sequence alignment revealed that SmCCR1 shares 83 % identity with CCR sequences reported in Camellia oleifera and other plant species. Expression pattern analysis indicated that expression of SmCCR1 can be induced by exposure to Xanthomonas campestris pv. Campestris or methyl jasmonate. To demonstrate its functioning, we selected a 296-bp fragment and established an RNA interference construct that was introduced into S. miltiorrhiza by Agrobacterium tumefaciens-mediated gene transfer. Transgenic plants exhibited dwarfing phenotypes, and both syringyl and guaiacyl lignin monomers were decreased more than 60 %. In contrast, biosynthesis of phenolic acids-danshensu, rosmarinic acid, and salvianolic acid B-was strongly induced by 2.03-, 1.41-, and 1.45-fold, respectively, in the roots of transgenic plants from line CCR-10. Consistent with these phytochemical changes, downregulation of SmCCR1 also affected the expression of related genes in the phenolics and lignin biosynthetic pathways. Our results also provide potential opportunities for engineering danshensu and salvianolic acid B production in S. miltiorrhiza. [ABSTRACT FROM AUTHOR]

Bletilla striata (Thunb.) Reichb.f., is a traditional Chinese medicine, and the Bletilla striata polysaccharide (BSP) is one of the principal components extracted from Bletilla striata with various biological activities. Previous studies have shown that many natural polysaccharides have significant immunomodulatory activities. However, as a plant polysaccharide, the research of BSP on immunomodulatory activities is limited. In this study, we aim to investigate the immunomodulatory effect of BSP in vivo and further explore its underlying mechanism in vitro. In vivo, a cyclophosphamide (CTX)-induced immunosuppression mice mode was established by intraperitoneal injection of CTX, and the immune-enhancing effect of BSP (25, 50 and 100 mg/kg) on immunosuppressed mice were evaluated. The result indicated that BSP could significantly improve the immune organ index and the content of immunoglobulin, TNF-α and IL-4 in serum. It was also found that BSP could clearly ameliorate the spleen damage induced by CTX. Meanwhile, the result showed that BSP could not only improve the proliferation of splenocytes, but also activate the lactate dehydrogenase (LDH) and acid phosphatase (ACP) in mouse spleen tissue. In vitro, potential mechanism was further revealed in macrophages. The result supported that BSP could activate macrophages with high phagocytic ability, and induce macrophages to secrete cytokines. Finally, it revealed that activation of NF-κB and MAPK signalling pathway should be the underlying mechanism of the immunoenhancment of BSP. [ABSTRACT FROM AUTHOR]

Interleukin (IL) 9, a dominant cytokine in Th9 cells, has been proven to play a pathogenic role in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), by augmenting T cell activation and differentiation; however, whether IL-9 signaling affects central nervous system (CNS)-resident cells during CNS autoimmunity remains unknown. In the present study, we found that the IL-9 receptor (IL-9R) was highly expressed in astrocytes, oligodendrocyte progenitor cells (OPCs), oligodendrocytes and microglia cells, and that its expression was significantly upregulated in brain and spinal cord during EAE. In addition, IL-9 increased chemokine expression, including CXCL9, CCL20 and MMP3, in primary astrocytes. Although IL-9 had no effect on the proliferation of microglia cells, it decreased OPC proliferation and differentiation when in combination with other pro-inflammatory cytokines, but not with IFN-γ. IL-9 plus IFN-γ promoted OPC proliferation and differentiation. These findings indicate that CNS-restricted IL-9 signaling may be involved in the pathogenesis of MS/EAE, thus providing a potential therapeutic target for future MS/EAE treatment through disruption of CNS cell-specific IL-9 signaling. [ABSTRACT FROM AUTHOR]

Acute lung injury (ALI) is characterized by an excessive inflammatory response, closely related to sepsis occurrence and development. It has been reported that Schisandrin (Sch) exhibits anti‐inflammatory activity. However, whether the beneficial effects of Sch exists during ALI remains to be studied. In this study, the impact of Sch was evaluated by studying lung tissue damage, measuring the concentrations of pro‐inflammatory factors, and the expression of apoptotic proteins in the LPS‐induced ALI mice model. Protein expression of inflammation‐related signaling pathway within the lung tissue and A549 cells were also measured. In addition, the effect of Sch on A549 cell apoptosis and inflammatory markers was also detected. Animal experiments demonstrated that pre‐feeding Sch alleviated the production of inflammation mediators, abnormal pathological injuries, and blocked the progression of apoptotic events in the lung tissue. The in vitro experiments showed that Sch pretreatment reduced LPS upregulated interleukin‐1β (IL‐1β), IL‐18, and IL‐6 levels, and improved LPS‐induced abnormal apoptosis. Sch and the pathway inhibitor AG490 also inhibited the expression levels of p‐JAK2 and p‐STAT3 in A549 cells. Moreover, pretreatment with Sch significantly inhibited the activation of NLRP3 inflammasomes, reduced inducible nitric oxide synthase, and cyclooxygenase 2 proteins expression during ALI in vitro and in vivo. Overall, Sch effectively alleviated ALI and provided a new mechanism to support the protective effect of Sch for sepsis‐induced ALI. Practical implications: ALI is characterized by inflammatory injury of the lungs, which is an important cause of high morbidity and mortality in severe patients. Sch is considered as a botanical active ingredient with various pharmacological activities, such as neuroprotective and vascular protective effects. However, the effect of Sch on ALI and its mechanism remains largely unknown. Research data indicate that Sch exerts an anti‐inflammatory effect by reducing the production of inflammatory factors and abnormal apoptosis of cells, further alleviating lung damage. The protective effect of Sch was associated with inhibition of the activation of NLRP3 and the JAK2/STAT3 inflammatory pathways. The study, therefore, confirmed that Sch has a potential as an effective drug to prevent ALI diseases. [ABSTRACT FROM AUTHOR]

The WRKY gene family is an important inducible regulatory factor in plants, which has been extensively studied in many model plants. It has progressively become the focus of investigation for the secondary metabolites of medicinal plants. Currently, there is no systematic analysis of the WRKY gene family in Scutellaria baicalensis Georgi. For this study, a systematic and comprehensive bioinformatics analysis of the WRKY gene family was conducted based on the genomic data of S. baicalensis. A total of 77 WRKY members were identified and 75 were mapped onto nine chromosomes, respectively. Their encoded WRKY proteins could be classified into three subfamilies: Group I, Group II (II-a, II-b, II-c, II-d, II-e), and Group III, based on the characteristics of the amino acid sequences of the WRKY domain and genetic structure. Syntenic analysis revealed that there were 35 pairs of repetitive fragments. Furthermore, the transcriptome data of roots, stems, leaves, and flowers showed that the spatial expression profiles of WRKYs were different. qRT-PCR analysis revealed that 11 stress-related WRKYs exhibited specific expression patterns under diverse treatments. In addition, sub cellular localization analysis indicated that SbWRKY26 and SbWRKY41 were localized in nucleus. This study is the first to report the identification and characterization of the WRKY gene family in S. baicalensis, which is valuable for the further exploration of the biological function of SbWRKYs. It also provides valuable bioinformatics data for S. baicalensis and provides a reference for assessing the medicinal properties of the genus. [ABSTRACT FROM AUTHOR]

Salvia miltiorrhiza Bunge, a well-known medicinal plant, has more than 20 effective components. The aim of this study was to comprehensively investigate foliar fungal endophyte communities of S. miltiorrhiza and explore the inside relationship between host-specific fungal endophytes and effective components accumulation. Five plant samples were collected from four geological different provinces in China. Foliar fungal endophyte communities were determined by terminal restriction fragment length polymorphism (T-RFLP) of the ITS region. Effective components were analyzed with high-performance liquid chromatography. The results showed that S. miltiorrhiza foliage harbored a large diversity of fungal endophytes. Principal component analysis revealed similar T-RFLP profiles and the characteristics of the 24 effective components among the five samples, which could be clustered into three groups. In foliar T-RFLP profiles derived from the restriction digestion by CfoI, HaeIII, MspI, or TaqI, there were identical 45, 42, 38, and 34 terminal restriction fragments (T-RFs) from the five samples. We consider these T-RFs as host-specific fungal endophytes. Correlation analysis of these T-RFs' area and 24 effective components contents revealed a significant correlationship between some host-specific fungal endophytes and foliage or root effective components accumulation. [ABSTRACT FROM AUTHOR]

Background: Tumor-associated macrophages (TAM)s are critical regulators of glioma progression. As yet, however, TAMs in isocitrate dehydrogenase (IDH) mutated lower-grade gliomas (LGGs) have not been thoroughly investigated. The aim of this study was to determine whether 1p/19q co-deletion status affects the TAM phenotype or its prevalence in IDH mutated LGGs. Methods: TAMs in IDH mutated LGGs were analyzed using transcriptome data from 230 samples in the TCGA database in combination with transcriptome data from single-cell RNA sequencing of IDH-mutated LGGs. Proteins potentially involved in TAM regulation were examined by immuno-staining in primary LGG samples harboring IDH mutations. Essential signaling pathways regulating TAM phenotypes were investigated in a glioma mouse model using small molecule inhibitors. Results: Most of the TAMs in IDH-mutated LGGs expressed the M1 activation markers CD86 and TNF, whereas a subset of individual TAMs co-expressed both M1 and M2-related markers. Bioinformatics analysis in combination with immuno-staining of IDH-mutated patient samples revealed higher amounts of TAMs expressing M2-related markers in 1p/19q non-codeletion IDH-mutated LGGs compared to 1p/19q codeletion LGGs. The levels of transforming growth factor beta 1 (TGFβ1) and macrophage colony-stimulating factor (M-CSF) were significantly higher in 1p/19q non-codeletion LGGs than in 1p/19q codeletion LGGs. M-CSF and TGFβ1 signal inhibition decreased tumor growth and modulated the TAM phenotype in a glioma mouse model. Conclusions: Our data indicate that 1p/19q co-deletion status relates to distinct TAM infiltration in gliomas, which is likely mediated by M-CSF and TGFβ1 signaling. M-CSF and TGFβ1 signaling may play a pivotal role in regulating the TAM phenotype in glioma. [ABSTRACT FROM AUTHOR]

The present study explored the changes in phytochemical profiles (proximate, amino acids, fatty acids, and lignans) and antioxidant activity of Schisandra sphenathera fruit with three maturity stages (un-ripen, semi-ripen and fully-ripen). The results showed that the whole fruit contained high levels of essential amino acids and unsaturated fatty acids (linoleic and oleic acids), whose content slightly reduced with maturity. Meanwhile, the contents of total phenolics, total flavonoids, and total tannins were generally decreased in the extractable, free, conjugated, and bound phenolic fractions, while the total anthocyanin content in these phenolic fractions were increased during ripening. Furthermore, the lignan profiling of these fractions indicated an increased content of schisandrol A and gomisin J, but a decreased content of schisandrin B and schisandrin C in the extractable phenolic fractions during fruit maturation. It was noted that schisantherin B and schisandrin A were recorded in all phenolic fractions, alongside schisandrin B and schisandrin C detected only in extractable form. Additionally, the extractable phenolic fractions exerted considerable antioxidant activity with little or low significance at three maturity stages. Therefore, the whole fruit of S. sphenathera abound with unsaturated fatty acids and antioxidant lignans, boosting its chances of being fully utilized as a versatile and economical crop in pharmaceutical and food industries for different purposes. • S. sphenathera fruit contained high levels of essential amino acids and unsaturated fatty acids. • Both extractable and non-extractable phenolics changed with ripening stages. • Lignan profiles of different phenolics fractions were also varied. • Schisantherin B and schisandrin A presented in free, conjugated and bound forms. [ABSTRACT FROM AUTHOR]

CLE peptides have been implicated in various developmental processes of plants and mediate their responses to environmental stimuli. However, the biological relevance of most CLE genes remains to be functionally characterized. Here, we report that CLE9, which is expressed in stomata, acts as an essential regulator in the induction of stomatal closure. Exogenous application of CLE9 peptides or overexpression of CLE9 effectively led to stomatal closure and enhanced drought tolerance, whereas CLE9 loss‐of‐function mutants were sensitivity to drought stress. CLE9‐induced stomatal closure was impaired in abscisic acid (ABA)‐deficient mutants, indicating that ABA is required for CLE9‐medaited guard cell signalling. We further deciphered that two guard cell ABA‐signalling components, OST1 and SLAC1, were responsible for CLE9‐induced stomatal closure. MPK3 and MPK6 were activated by the CLE9 peptide, and CLE9 peptides failed to close stomata in mpk3 and mpk6 mutants. In addition, CLE9 peptides stimulated the induction of hydrogen peroxide (H2O2) and nitric oxide (NO) synthesis associated with stomatal closure, which was abolished in the NADPH oxidase‐deficient mutants or nitric reductase mutants, respectively. Collectively, our results reveal a novel ABA‐dependent function of CLE9 in the regulation of stomatal apertures, thereby suggesting a potential role of CLE9 in the stress acclimatization of plants. CLE peptides have been implicated in various developmental processes of plants and mediate their responses to environmental stimuli. Here, we reported an essential role of CLE9 in the induction of stomatal closure. CLE9 stimulated stomatal closure in an ABA‐dependent manner, accompanied with H2O2/NO production. Further investigation revealed that OST1, SLAC1, and MPK3/MPK6 are required for CLE9‐mediated guard cell signalling. [ABSTRACT FROM AUTHOR]

Scutellaria baicalensis is a flowering plant of the Lamiaceae genus whose petals are mostly purple, with a few being pink and white. To elucidate the kinetics behind S. baicalensis petal coloration, an integrative analysis of target flavonoid metabolic and transcriptome profiles was performed to identify the anthocyanin biosynthesis pathway, which was differently activated in S. baicalensis germplasms with three different petal colors (white, pink and purple). Metabolomic profile data revealed that 18 anthocyanins were significantly different in S. baicalensis petals. Transcriptomic data showed that S. baiANS in anthocyanin biosynthesis was significantly downregulated in white flower petals. Interestingly, the sequence variations were found in the S. baiANS promoter region, where it was likely that a mutation reduced S. baiANS expression in white S. baicalensis flowers. Yeast one-hybrid (Y1H) analysis of S. baiMYB indicated that it was not bound to the S. baiANS promoters of white S. baicalensis flowers. Dual-luciferase assays further confirmed that the S. baiANS promoter decreased promoter activity, which resulted in reduced anthocyanin biosynthesis in white S. baicalensis flowers. The findings of this study elucidate the mechanisms behind the loss-of-color phenotype in white S. baicalensis flowers while providing potential leads for further studies on biological and flower evolution. [Display omitted] • Eighteen types of anthocyanins were detected in three S. baicalensis germplasms. • S. baiANS were significantly differentially expressed in White-F S. baicalensis. • Variations in the promoter region resulted in a loss-of-color phenotype. • S.baiMYB transcription factors did not regulate S. baiANS to influence the formation of flower color. [ABSTRACT FROM AUTHOR]

Abstract: The membrane lipid peroxidation, antioxidant metabolites, as well as ultrastructure of chloroplasts of leaves were investigated in two cool-season turfgrass species, perennial ryegrass (heat sensitive) and tall fescue (moderate), exposed to three heat stress levels (38, 42, 46°C) for 14h, respectively, with a heat acclimation pretreatment at 30°C for 3 days in a growth chamber. Relative water content (RWC), cell membrane thermostability, malondialdehyde (MDA) content, accumulation of hydrogen peroxide (H2O2) and superoxide (O2 −), ascorbate (AsA) and glutathione (GSH) contents were measured in leaves. RWC decreased with increase in heat stress levels in tall fescue and perennial ryegrass leaves. However, leaves with heat acclimation pretreatment kept lower decrease in RWC than those without heat acclimation pretreatment at three heat stress levels. Under heat stresses, leaves heat-acclimated pretreatment in two turfgrass species maintained higher membrane thermostability and lower membrane lipid peroxidation product (MDA) than those in no heat-acclimated leaves; however, perennial ryegrass leaves showed greater membrane injury than tall fescue leaves regardless of heat acclimation pretreatment, especially at 46°C. Significant accumulation of H2O2 and O2 − was observed in two turfgrass species leaves regardless of heat-acclimated pretreatment at all stress levels; however, their degree of accumulation kept lower level in heat-acclimated leaves than in no heat-acclimated leaves. AsA and GSH are two important metabolites in antioxidant system in plants. Our results showed the contents of AsA and GSH in heat-acclimated leaves were higher than those in control at same heat stress level though the contents of AsA and GSH showed the trend of significant decrease with increase in heat stress levels. After heat acclimation pretreatment, ultrastructure of chloroplasts had lower damage in two turfgrass species leaves under heat stress than those without heat acclimation pretreatment, which may contribute to the decrease in membrane lipid peroxidation, increase in AsA and GSH contents at same heat stress level. However, it was insufficient to protect the chloroplast from damage with increase in heat stress level, even if with high AsA and GSH contents to remove reactive oxygen species (ROS). [Copyright &y& Elsevier]