沈阳药科大学

This study aimed to systematically identify the rice SPX gene family at the whole-genome level,characterize its evolu-tionary features and expression patterns,and provide a basis for elucidating SPX functions in phosphorus signal transduction.Bioinformatics approaches were used to identify SPX genes in rice and to analyze their physicochemical properties,phylogenetic relationships,gene structures,conserved motifs,promoter cis-acting elements,and collinearity.Transcriptomic data and quantita-tive real-time PCR(RT-qPCR)were used to examine tissue-specific expression and responses to phosphorus stress.Six SPX genes were identified and mapped to five chromosomes.Phylogenetic analysis showed that OsSPX1 and OsSPX2 clustered together with 100%bootstrap support,whereas OsSPX3 formed a well-supported subclade with OsSPX5 and OsSPX6.Collinearity analy-sis identified two segmental duplication pairs(OsSPX1/OsSPX2 and OsSPX5/OsSPX6),and all Ka/Ks values were<1(0.19-0.44),indicating strong purifying selection.Gene structure analysis showed that OsSPX members contain 2-3 exons,and conserved motif distributions were highly consistent with the phylogenetic relationships.Promoter analysis identified 135 cis-acting ele-ments,mainly related to hormone,light,and stress responses,with methyl jasmonate-and abscisic acid-responsive elements being the most abundant.RT-qPCR analysis in the ShijinB variety indicated that OsSPX1-OsSPX6 were preferentially expressed in roots,with OsSPX3 also showing relatively high expression in inflorescences and OsSPX1 and OsSPX4 showing relatively high expression in leaves.Under low-phosphorus conditions,OsSPX1,OsSPX2,OsSPX3,OsSPX5,and OsSPX6 were significantly upregulated,with OsSPX3 showing the strongest induction,whereas OsSPX4 was not affected by phosphorus availability.Overall,the rice SPX gene family appears to have expanded via segmental duplication and subsequently evolved under purifying selection;although gene structures and motif compositions are relatively conserved,members show clear tissue specificity and differential responsiveness to phosphorus stress.

We undertook this study to evaluate the structure and immunomodulatory activity of polysaccharides from dried Siraitia grosuenorii fruits.The crude polysaccharides were obtained by water extraction followed by alcohol precipitation and purified and separated into two homogeneous fractions:SGP-C2 and SGP-D1 through sequential Cellulose DE-52 and Sephadex G-200 column chromatography.The monosaccharide compositions and molecular masses of SGP-C2 and SGP-D1 were analyzed by pre-column derivatization with 1-phenyl-3-methyl-5-pyrazolone(PMP)followed by high performance liquid chromatography(HPLC)equipped with a refractive index detector(RID).Their structures were characterized by Fourier transform infrared spectrometer(FTIR)and nuclear magnetic resonance(NMR)spectroscopy.Their immunomodulatory activity was evaluated by the neutral red colorimetric assay,their activity to induce the release of reactive oxygen species(ROS)from RAW264.7 cells was tested using 2',7'-dichlorodihydrofluorescein diacetate(DCFH-DA)as the fluorescent probe,and their activity to induce NO production and the secretion of tumor necrosis factor-α(TNF-α)and interleukin-6(IL-6)in RAW264.7 cells was examined using a Griess kit and an enzyme-linked immunosorbent assay(ELISA)kit,respectively.SGP-C2 and SGP-D1 were heteropolysaccharides composed of glucuronic acid,rhamnose,galacturonic acid,glucose,galactose and arabinose with mole ratios of 0.78:1.84:26.57:1.31:0.49:0.06 and 1.37:2.00:20.79:0.61:0.12:0.25,respectively.Their relative molecular masses were 5.0×105 and 7.6×105 Da,respectively.NMR analysis showed that the backbone chain structure of SGP-C2 was →4)-α-D-GalpA-(1→ and →4)-α-D-GalpAMe-(1→,while that of SGP-D1 was →4)-α-D-Galp A-(1→.In the concentration range of 6.25-25 µg/mL,both polysaccharides promoted macrophage phagocytosis,NO production,and the secretion of TNF-α and IL-6.Besides,SGP-D1 significantly promoted the release of ROS.These results showed that SGP-C2 and SGP-D1 had immune-enhancing effects in vitro.This study provides the scientific basis for the development and application of polysaccharides from S.grosuenorii.

Background:The previous research has confirmed the existence of idiosyncratic drug-induced liver injury(IDILI)caused by Polygonum multiflorum(PM-IDILI),and demonstrated that PM-IDILI is an immune-mediated injury,with HLA-B*35:01 identified as a genetic suscep-tibility marker.Additionally,emodin-8-O-β-D-glucoside(EG)and 2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside have been pro-posed as potential contributory ingredients in the pathogenesis of PM-IDILI.However,the precise mechanisms through which these susceptible factors contribute to the development of PM-IDILI remain unclear. Objectives:This study aims to explore the molecular characteristics of HLA-B*35:01 that contribute to PM-DILI and to propose a mechanistic hypothesis based on our previous research on PM-induced protein adducts. Methods:Key differences between HLA-B*35:01 and general Chinese HLA-B alleles were identified by comparing protein sequences,peptide binding motifs,and protein structures.Molecular docking was employed to assess whether PM-induced haptenated peptides can be presented by HLA-B*35:01 and other related alleles.Additionally,a simplified dipeptide model was used to evaluate the binding affinity of HLA-B*35:01 to EG-haptenated peptides. Results:Our findings revealed significant differences in the residues of the B and F peptide binding pockets of HLA-B*35:01 compared to general Chinese HLA-B alleles.Further analysis suggested that the F pocket of HLA-B*35:01 was capable of binding EG-cysteine adducts and might be a key feature in the PM-IDILI pathogenesis.Peptide docking using DINC and molecular dynamics simulations indicated that HLA-B*35:01 could form stable complexes with EG-haptenated peptides.Molecular dynamics simulations also highlighted the critical roles of both the B and F pockets in peptide binding.Specifically,the F pocket binds the EG-modified residue in haptenated peptides,while the B pocket,despite lacking shared features among PM-IDILI patients,may indirectly influence the inci-dence of PM-IDILI by filtering haptenated peptides.The binding affinity of HLA-B*35:01 to EG-modified cysteine residues was experi-mentally validated through a dipeptide-based assay,confirming that HLA-B*35:01 could bind EG-haptenated peptides. Conclusions:This study identified the unique B and F binding pockets of HLA-B*35:01 as key factors in PM-IDILI pathogenesis and demonstrated that HLA-B*35:01 could bind EG-haptenated peptides.These findings suggest that PM-IDILI may be a hapten-based drug hypersensitivity reaction driven by EG,providing a theoretical framework for further research aimed at elucidating the molecular mechanisms underlying PM-IDILI.

Hyperuricemia is a prevalent metabolic disorder resulting from dysregulation of purine metabolism, often accompanied by inflammation. It is characterized by an abnormal elevation in uric acid (UA) levels. In our investigation, the combined treatment with Lactiplantibacillus plantarum DY1 and quercetin suppressed the activity of xanthine oxidase and adenosine deaminase, decreased the levels of UA, tumor necrosis factor alpha (TNF-α) and interleukin 1β (IL-β), downregulated gene expression of urate transporter 1 (URAT1) and glucose transporter 9 (GLUT9), and upregulated organic anion transporter 1 (OAT1) and ATP-binding cassette transporter subfamily G member 2 (ABCG2). The combination increased the abundance of Lactobacillus and decreased the abundance of norank_f_norank_o__Clostridia_UCG-014 and Roseburia. Metabolomics analysis revealed that the combination of probiotics and quercetin exhibited distinct metabolic pathways compared to their individual administrations. When compared to probiotics alone, the combination led to alterations in glutathione metabolism (oxidized glutathione and glutathione) as well as sphingolipid metabolism (sphingosine and sphinganine). When compared to quercetin alone, the combination resulted in variations in tryptophan metabolism (indole-3-acetamide, 5-hydroxy-L-tryptophan, indoleacetaldehyde, 3-(3-indolyl)-2-oxopropanoic acid, 3-indoleacetic acid and 3-methylindole) along with purine metabolism (UA, xanthosine, cyclic adenosine monophosphate (cAMP), adenosine diphosphate (ADP) and adenosine monophosphate (AMP)). The subsequent fecal microbiota transplantation proved that the effect of the combination on reducing UA levels was mediated by the gut microbiota. Therefore, this new combination can be considered a promising adjuvant therapy capable of synergistically alleviating hyperuricemia.

The fluorescent molecule capable of recognizing 10-hydroxycamptothecin (HCPT), a broad-spectrum anti-tumor drug, is not only able to detect it, but also able to enhance its activity due to the improvement of the delivery. Therefore, the construction of highly selective fluorescent hosts of HCPT is valuable, but remains challenging. In this work, an amphiphilic carbazole macrocyclic molecule (3) was synthesized and the host-guest interaction between 3 and HCPT was studied by fluorescence spectroscopy, NMR, scanning electron microscopy and transmission electron microscopy. The results showed that 3 could recognize HCPT with a stoichiometric ratio of 2 & ratio;1 via the mechanism of fluorescence resonance energy transfer (FRET) and a binding constant of 1.26x1014 (mol/L)(-2). The detection of limit (LOD) is 11.7 nmol center dot L-1. In addition, the complexation enhanced the activity of HCPT to inhibit the proliferation of MCF-7 (Michigan Cancer Foundation-7) cells in vitro, and the IC50 value decreased by two orders of magnitude, indicating that 3 possessed the dual function of both fluorescence probe and molecular carrier, thus providing scientific basis for further research.