Stem-leaf saponins from Panax notoginseng (SLSP) comprise numerous PPD-type saponins with diverse pharmacological properties; however, their role in Parkinson's disease (PD), characterized by microglia-mediated neuroinflammation, remains unclear. This study evaluated the effects of SLSP on suppressing microglia-driven neuroinflammation in experimental PD models, including the 1-methyl-4-phenylpyridinium (MPTP)-induced mouse model and lipopolysaccharide (LPS)-stimulated BV-2 microglia. Our findings revealed that SLSP mitigated behavioral impairments and excessive microglial activation in models of PD, including MPTP-treated mice. Additionally, SLSP inhibited the upregulation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2) and attenuated the phosphorylation of PI3K, protein kinase B (AKT), nuclear factor-κB (NFκB), and inhibitor of NFκB protein α (IκBα) both in vivo and in vitro. Moreover, SLSP suppressed the production of inflammatory markers such as interleukin (IL)-1β, IL-6, and tumor necrosis factor alpha (TNF-α) in LPS-stimulated BV-2 cells. Notably, the P2Y2R agonist partially reversed the inhibitory effects of SLSP in LPS-treated BV-2 cells. These results suggest that SLSP inhibit microglia-mediated neuroinflammation in experimental PD models, likely through the P2Y2R/PI3K/AKT/NFκB signaling pathway. These novel findings indicate that SLSP may offer therapeutic potential for PD by attenuating microglia-mediated neuroinflammation.
Animals ; Panax notoginseng/chemistry* ; Saponins/pharmacology* ; Microglia/immunology* ; Mice ; NF-kappa B/immunology* ; Signal Transduction/drug effects* ; Proto-Oncogene Proteins c-akt/immunology* ; Phosphatidylinositol 3-Kinases/genetics* ; Male ; Parkinson Disease/immunology* ; Mice, Inbred C57BL ; Disease Models, Animal ; Plant Leaves/chemistry* ; Neuroinflammatory Diseases/drug therapy* ; Humans

A comprehensive phytochemical investigation of the leaves and twigs of Physalis angulata. var. villosa resulted in the isolation of 23 withanolide derivatives, including one novel 13,20-γ-lactone withanolide derivative (1) and three new withanolide derivatives (2-4). Architecturally, physalinin A (1) represents the first identified type B withanolide featuring a 13,20-γ-lactone moiety. The molecular structures of all isolates were elucidated using an integrated approach combining nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry (MS), infrared (IR) spectroscopy, and quantum chemical calculations to confirm structural assignments. The antiproliferative activities of all isolated withanolides were evaluated against four human cancer cell lines (HEL, HCT-116, Colo320DM, and MDA-MB-231). Among them, eight derivatives (2, 5-8, 14, 15, and 23) exhibited significant inhibitory effects, with half-maximal inhibitory concentration (IC₅₀) values of 0.18 ± 0.03 to 17.02 ± 0.21 μmol·L^-1. Structure-activity relationship (SAR) analysis suggested that the presence of an epoxide ring enhances anticancer activity, potentially through increased reactivity or specific interactions with molecular targets involved in cancer progression. These findings underscore the pharmacological potential of withanolides as promising lead compounds for the development of novel anticancer therapeutics.
Withanolides/isolation & purification* ; Physalis/chemistry* ; Humans ; Molecular Structure ; Cell Line, Tumor ; Antineoplastic Agents, Phytogenic/isolation & purification* ; Cell Proliferation/drug effects* ; Plant Leaves/chemistry* ; Plant Extracts/pharmacology*

The anti-inflammatory phytochemical investigation of the leaves of Illicium dunnianum (I. dunnianum) resulted in the isolation of five pairs of new lignans (1-5), and 7 known analogs (6-12). The separation of enantiomer mixtures 1-5 to 1a/1b-5a/5b was achieved using a chiral column with acetonitrile-water mixtures as eluents. The planar structures of 1-2 were previously undescribed, and the chiral separation and absolute configurations of 3-5 were reported for the first time. Their structures were determined through comprehensive spectroscopic data analysis [nuclear magnetic resonance (NMR), high-resolution electrospray ionization mass (HR-ESI-MS), infrared (IR), and ultraviolet (UV)] and quantum chemistry calculations (ECD). The new isolates were evaluated by measuring their inhibitory effect on NO in lipopolysaccharide (LPS)-stimulated BV-2 cells. Compounds 1a, 3a, 3b, and 5a demonstrated partial inhibition of NO production in a concentration-dependent manner. Western blot and real-time polymerase chain reaction (PCR) assays revealed that 1a down-regulated the messenger ribonucleic acid (mRNA) levels of tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), COX-2, and iNOS and the protein expressions of COX-2 and iNOS. This research provides guidance and evidence for the further development and utilization of I. dunnianum.
Lignans/isolation & purification* ; Plant Leaves/chemistry* ; Anti-Inflammatory Agents/isolation & purification* ; Mice ; Animals ; Molecular Structure ; Plant Extracts/pharmacology* ; Illicium/chemistry* ; Cyclooxygenase 2/immunology* ; Interleukin-6/immunology* ; Nitric Oxide/metabolism* ; Cell Line ; Tumor Necrosis Factor-alpha/immunology* ; Nitric Oxide Synthase Type II/immunology* ; Lipopolysaccharides

The OsSPL10 gene has previously been reported to positively regulate trichome development and negatively regulate salt and drought stress tolerance in rice. However, it is not clear whether this gene can be used for gene editing to create new germplasm of glabrous leaf and salt-tolerant rice. In this study, we created six rice mutants by CRISPR/Cas9-mediated editing of OsSPL10 from 'Xinfeng 2', 'Xinkedao 31', and 'Xindao 25', the main rice cultivars along the Yellow River. Visual observation and scanning electron microscopy verified that the mutants lacked trichomes on the leaves and glumes, and the expression of glabrous marker genes OsHL6, OsGL6, and OsWOX3B in mutants was down-regulated compared with that in the wild type. The net photosynthetic rate, stomatal conductance, and transpiration rate of flag leaves in the mutants were significantly higher than those in the wild type. In addition, the survival rates of the mutants were much higher than that of the wild type after 7 days of treatment with 200 mmol/L NaCl. The results of quantitative real-time polymerase chain reaction (qRT-PCR) further verified that compared with the wild type, the mutants demonstrated down-regulated expression of the salt stress-related gene OsGASR1 and up-regulated expression of OsNHX2 and OsIDS1. Statistical analysis of agronomic traits showed that the mutants had increased plant height and no significant changes in yield-related traits compared with the wild type. The six spl10 mutants created in this study not only had glabrous leaves and glumes but also demonstrated enhanced tolerance to salt stress, serving as new germplasm resources for directional breeding of rice along the Yellow River.
Oryza/physiology* ; CRISPR-Cas Systems/genetics* ; Salt Tolerance/genetics* ; Gene Editing/methods* ; Plant Proteins/genetics* ; Rivers ; Plant Leaves/genetics* ; Mutation ; Plants, Genetically Modified/genetics* ; China

Microalgae possess high photosynthetic efficiency, robust adaptability, and substantial biomass, serving as excellent biological resources for large-scale cultivation. Malic enzyme (ME), a ubiquitous metabolic enzyme in living organisms, catalyzes the decarboxylation of malate to produce pyruvate, CO₂, and NAD(P)H, playing a role in multiple metabolic pathways including energy metabolism, photosynthesis, respiration, and biosynthesis. In this study, we identified the Scenedesmus quadricauda malic enzyme gene (SqME) and its biological functions, aiming to provide excellent target genes for the genetic improvement of higher plants. Based on the RNA-seq data from S. quadricauda under the biofilm cultivation mode with high CO₂ and light energy transfer efficiency and small water use, a highly expressed gene (SqME) functionally annotated as ME was cloned. The physicochemical properties of the SqME-encoded protein were systematically analyzed by bioinformatics tools. The subcellular localization of SqME was determined via transient transformation in Nicotiana benthamiana leaves. The biological functions of SqME were identified via genetic transformation in Nicotiana tabacum, and the potential of SqME in the genetic improvement of higher plants was evaluated. The ORF of SqME was 1 770 bp, encoding 590 amino acid residues, and the encoded protein was located in chloroplasts. SqME was a NADP-ME, with the typical structural characteristics of ME. The ME activity in the transgenic N. tabacum plant was 1.8 folds of that in the wild-type control. Heterologous expression of SqME increased the content of chlorophyll a, chlorophyll b, and total chlorophyll by 20.9%, 26.9%, and 25.2%, respectively, compared with the control. The transgenic tobacco leaves showed an increase of 54.0% in the fluorescence parameter NPQ and a decrease of 30.1% in Fo compared with the control. Moreover, the biomass, total lipids, and soluble sugars in the transgenic tobacco leaves enhanced by 20.5%, 25.7%, and 9.5%, respectively. On the contrary, the starch and protein content in the transgenic tobacco leaves decreased by 22.4% and 12.2%, respectively. Collectively, the SqME-encoded protein exhibited a strong enzymatic activity. Heterologous expressing of SqME could significantly enhance photosynthetic protection, photosynthesis, and biomass accumulation in the host. Additionally, SqME can facilitate carbon metabolism remodeling in the host, driving more carbon flux towards lipid synthesis. Therefore, SqME can be applied in the genetic improvement of higher plants for enhancing photosynthetic carbon fixation and lipid accumulation. These findings provide scientific references for mining of functional genes from S. quadricauda and application of these genes in the genetic engineering of higher plants.
Nicotiana/genetics* ; Photosynthesis/physiology* ; Malate Dehydrogenase/biosynthesis* ; Plant Leaves/genetics* ; Scenedesmus/enzymology* ; Carbon Cycle/genetics* ; Lipid Metabolism/genetics* ; Plants, Genetically Modified/metabolism*

Rice (Oryza sativa L.) is an important food crop. The appearance of lesion mimics in rice leads to phytohormone disorders, which affects rice adaptation to environmental stresses and ultimately reduces the yield and quality. To explore whether the changes in the adaptability of rice lesion-mimic mutants to stressful environments are caused by the disorder of phytohormone metabolism in plants. In this study, we screened an ethyl methane sulfonate-treated population of the japonica cultivar 'Taipei 309' for a mutant with rust-like spots on leaves at the early tillering stage and brown-red spots at maturity and named it rsl1 (rust spotted leaf 1). Compared with the wild type, rsl1 showed decreases in plant height, panicle length, primary branch number, secondary branch number, filled grains per panicle, seed-setting rate, and 1 000-grain weight, and an increase in number of effective panicles. Genetic analysis indicated that rsl1 was controlled by a single recessive nuclear gene. RSL1 was localized between two molecular markers, B7-7 and B7-9, on rice chromosome 7 by map-based cloning. PCR sequencing of the annotated genes in this interval revealed a mutation of C1683A on the eighth exon of SPL5 (LOC_Os07g10390) in rsl1, which resulted in premature termination of protein translation. Exogenous phytohormone treatments showed that rsl1 was less sensitive to salicylic acid (SA), abscisic acid (ABA), and indo-3-acetic acid (IAA) and more sensitive to methyl jasmonate (MeJA) and gibberellin acid (GA) than the wild type. In addition, the survival rate of rsl1 was lower than that of the wild type under salt, alkali, drought, and high temperature stresses, and it was higher than that of the wild type under cold stress. Quantitative real-time polymerase chain reaction (qRT-PCR) results showed that RSL1 was involved in the regulation of ABA, SA, MeJA, IAA, and GA-related genes under abiotic stresses. The present study showed that the RSL1 mutation led to the appearance of lesion mimics and affected the growth, development, and stress resistance of rsl1 under abiotic stresses. The study of the functional mechanism of this gene can provide theoretical guidance for the research on rice stress resistance.
Oryza/microbiology* ; Stress, Physiological/genetics* ; Plant Diseases/genetics* ; Cloning, Molecular ; Chromosome Mapping ; Plant Growth Regulators/metabolism* ; Plant Proteins/genetics* ; Mutation ; Cyclopentanes ; Genes, Plant ; Plant Leaves/genetics* ; Oxylipins

To explore the feasibility of using UAV-LiDAR for measuring the leaf area index (LAI) of crop canopies, we employed UAV-LiDAR to scan sugarcane canopies during the tillering and elongation stages, acquiring canopy point cloud data. Subsequently, features such as average row height, projected row area, point cloud density at different canopy layers, and the ratios between these parameters were extracted. Three feature selection methods-partial least squares regression (PLSR), XGBoost feature importance (XGBoost-FI), and random forest-recursive feature elimination (RF-RFE)-were adopted to evaluate and identify the optimal input variables for modeling. With these selected variables, LAI inversion models were developed based on random forest (RF) and adaptive boosting (AdaBoost) algorithms, and their performance was assessed. Among the extracted features, the projected row area S_p and the total row point count C_total exhibited strong correlations with LAI, with correlation coefficients of 0.73 and 0.72, respectively. The AdaBoost-based LAI inversion model, using the projected row area S_p, average height H_avg, mid-layer point cloud density C_m, and total row point count C_total as input variables, achieved the best performance, with a coefficient of determination (R_v²) of 0.713 and a root mean square error (RMSE_v) of 0.25 on the validation set. This study provides an effective method for high-throughput acquisition of LAI in field crops, offering valuable scientific support for sugarcane field management and breeding efforts.
Plant Leaves/growth & development* ; Saccharum/growth & development* ; Algorithms ; Unmanned Aerial Devices ; Remote Sensing Technology/methods* ; Crops, Agricultural/growth & development*

To study the differences in transcript levels among different organs of Spatholobus suberectus and to explore the genes encoding enzymes related to the catechin biosynthesis pathway, this study utilized the genome and full-length transcriptome data of S. suberectus as references. Transcriptome sequencing and bioinformatics analysis were performed on five different organs of S. suberectus-roots, stems, leaves, flowers, and fruits-using the Illumina NovaSeq 6000 platform. A total of 115.28 Gb of clean data were obtained, with GC content values ranging from 45.19% to 47.54%, Q20 bases at 94.17% and above, and an overall comparison rate with the reference genome around 90%. In comparisons between the stem and root, stem and leaf, stem and flower, and stem and fruit, 10 666, 9 674, 9 320, and 5 896 differentially expressed genes(DEGs) were identified, respectively. The lowest number of DEGs was found in the stem and root comparison group. KEGG enrichment analysis revealed that the DEGs were mainly concentrated in the pathways of phytohormone signaling, phenylalanine biosynthesis, etc. A total of 39 genes were annotated in the catechin biosynthesis pathway, with at least one highly expressed gene found in all organs. Among these, PAL1, PAL2, C4H1, C4H3, 4CL1, 4CL2, and DFR2 showed high expression in the stems, suggesting that they may play important roles in the biosynthesis of flavonoids in S. suberectus. This study aims to provide important information for the in-depth exploration of the regulation of catechin biosynthesis in S. suberectus through transcriptome analysis of its different organs and to provide a reference for the further realization of S. suberectus varietal improvement and molecular breeding.
Catechin/biosynthesis* ; Gene Expression Profiling ; Gene Expression Regulation, Plant ; Plant Proteins/metabolism* ; Fabaceae/metabolism* ; Transcriptome ; Flowers/metabolism* ; Plant Stems/metabolism* ; Plant Leaves/metabolism* ; Plant Roots/metabolism* ; Fruit/metabolism*

The balance between growth and defense in response to nearby or canopy shading in heliotropic plants has been deeply understood. However, the adaptive traits developed by shade-tolerant plants through long-term evolution remain unclear. In this study, the typical shade-tolerant medicinal plant Anoectochilus roxburghii was used as the experimental material.(1) Different planting densities were set, including 8 cm(row spacing) × 8 cm(plant spacing), 6 cm × 6 cm, 4 cm × 4 cm, and 2 cm × 2 cm, to monitor the individual plant responses to nearby shading.(2) Different light environments, including blue light∶red light=3∶2(B3R2), blue light∶red light∶far-red light=3∶2∶1(B3R2FR1), blue light∶red light∶far-red light=3∶2∶2(B3R2FR2), and blue light∶red light∶far-red light=3∶2∶4(B3R2FR4), were set to monitor the morphological and physiological changes in plants in response to actual shading conditions. The results showed that:(1) Moderate increases in planting density helped optimize morphological traits such as stem diameter and leaf area. This not only slightly increased biomass but also significantly improved SOD activity in both leaves and stems, as well as lignin content in stems, thereby enhancing the plant's defense capabilities.(2) Increasing the far-red light in the light environment negatively regulated the plant height of A. roxburghii, which was contrary to the typical shade-avoidance response observed in heliotropic plants. However, it significantly enhanced SOD and POD activity in both stems and leaves, as well as lignin content in stems. Furthermore, it reduced the incidence and disease index of stalk rot, effectively defending against biotic stress. Therefore, the shade-tolerant plant A. roxburghii has specific adaptive strategies for shading conditions. Reasonable dense planting or light environment modulation can synergistically improve yield, medicinal quality, and resistance of A. roxburghii. This study provides a theoretical foundation and technical support for optimizing the regional deployment and cultivation strategies of ecological planting for Chinese medicinal materials.
Orchidaceae/genetics* ; Light ; Plant Leaves/physiology* ; Sunlight ; Adaptation, Physiological/radiation effects* ; Plant Proteins/genetics*

This study aimed to characterize and identify the non-volatile components in aqueous and ethanolic extracts of the stems and leaves of Rhododendron tomentosum by using sensitive and efficient ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry(UHPLC-Q-TOF-MS) combined with a self-built information database. By comparing with reference compounds, analyzing fragment ion information, searching relevant literature, and using a self-built information database, 118 compounds were identified from the aqueous and ethanolic extracts of R. tomentosum, including 35 flavonoid glycosides, 15 phenolic glycosides, 12 flavonoids, 7 phenolic acids, 7 phenylethanol glycosides, 6 tannins, 6 phospholipids, 5 coumarins, 5 monoterpene glycosides, 6 triterpenes, 3 fatty acids, and 11 other types of compounds. Among them, 102 compounds were reported in R. tomentosum for the first time, and 36 compounds were identified by comparing them with reference compounds. The chemical components in the ethanolic and aqueous extracts of R. tomentosum leaves and stems showed slight differences, with 84 common chemical components accounting for 71.2% of the total 118 compounds. This study systematically characterized and identified the non-volatile chemical components in the ethanolic and aqueous extracts of R. tomentosum for the first time. The findings provide a reference for active ingredient research, quality control, and product development of R. tomentosum.
Rhododendron/chemistry* ; Chromatography, High Pressure Liquid/methods* ; Drugs, Chinese Herbal/chemistry* ; Mass Spectrometry/methods* ; Plant Leaves/chemistry*