[Effect of Polygonati Rhizoma aqueous extract on chronic obstructive pulmonary disease in rats].

This study aimed to investigate the effects and potential mechanism of Polygonati Rhizoma aqueous extract on chronic obstructive pulmonary disease(COPD) in rats. Forty-eight Sprague-Dawley rats were randomly assigned to the normal, model,Yupingfeng Granules(1. 5 g·kg~(-1)), and low-, medium-, and high-dose(0. 25, 0. 5, and 1 g·kg~(-1), respectively) Polygonati Rhizoma aqueous extract groups. The rat model of COPD was established by cigarette smoke inhalation for 8 weeks, and then the modeled rats received corresponding treatment for 4 weeks. The grip strength and fecal moisture content were measured, and the lung index was calculated. Enzyme-linked immunosorbent assay(ELISA) was employed to determine the levels of interleukin(IL)-6 and tumor necrosis factor(TNF)-α in the lung tissue. Hematoxylin-eosin(HE) staining and Masson staining were performed to assess the pathological changes in the lung tissue. Flow cytometry was used to analyze T lymphocytes and their subpopulations in the peripheral blood, and the immunofluorescence assay and Western blot were employed to measure the protein levels of Toll-like receptor 4(TLR4), phosphorylated nuclear factor-kappaB(p-NF-κB), NF-κB, phosphorylated inhibitory kappa B-α(p-IκBα), IκBα, IL-6,and TNF-α in the lung tissue. The results indicated that the treatment with Polygonati Rhizoma aqueous extract significantly reduced the fecal moisture content, enhanced the grip strength, and inhibited inflammatory infiltration and fibrosis in the lung tissue. The treatment increased the Th/Tc ratio and Th cell proportion and decreased the Tc cell proportion in the peripheral blood. Furthermore,the treatment down-regulated the expression levels of TLR4, IL-6, and TNF-α and the p-NF-κB/NF-κB and p-IκBα/IκBα ratios in the lung tissue. In conclusion, Polygonati Rhizoma aqueous extract can ameliorate lung tissue damage in the rat model of COPD by inhibiting the TLR4/NF-κB signaling pathway and the production of inflammatory mediators.

Development of SSR markers for genetic diversity analysis and species identification in Polygonatum odoratum (Mill.) Druce based on transcriptome sequences.

Polygonatum odoratum (Mill.) Druce is a well-known traditional Chinese herb belonging to the Polygonatum. However, the understanding of the genetic diversity of this species at the molecular level is limited due to the lack of transcriptomic and genomic information. In this study, 37,387 unigenes were assembled based on the transcriptome sequencing of the rhizome of Polygonatum odoratum (Mill.) Druce., and 11,021 single- sequence repeats (SSR) motifs, mainly consisting of single-nucleotide repeats (44.44%), dinucleotides (31.06%), and trinucleotides (22.59%), were identified. Based on these SSR motifs, 9,987 primer pairs of SSR markers were designed and 68 SSR markers were randomly selected for verification, of which 21 SSR markers showed polymorphisms among the 24 Polygonatum odoratum germplasms. Ninety-four alleles were detected: the observed alleles ranged from 2 to 11, the effective alleles varied from 1.086 8 to 4.916 8, the Shannon diversity index was 0.173 2~1.749 7, and the polymorphism information content PIC ranged from 0.076 7 to 0.803 9. Based on our analysis of genetic diversity (SSR genotypes) and population structure, we divided the 24 germplasm resources into two groups, indicating that the germplasm with similar geographical origins can be grouped together. In addition, the primers 'YZ14' and 'YZ47' could effectively distinguished the related species: Polygonatum kingianum Coll.et Hemsl., Polygonatum sibiricum Red., Polygonatum cyrtonema Hua, Polygonatum zanlanscianense Pamp. and Polygonatum odoratum (Mill.) Druce. This is the first study in which a dataset of expressed sequence tag (EST)-SSR markers is constructed for the Polygonatum odoratum (Mill.) Druce, and these newly developed EST-SSR markers provided a very efficient tool for genetic relationship analysis, species identification and marker-assisted selection breeding of Polygonatum odoratum (Mill.) Druce.

Genomic Investigation of a Rhizosphere Isolate, Streptomyces sp. JL1001, Associated with Polygonatum cyrtonema Hua.

In the present study, using genome mining, Streptomyces sp. JL1001, which possesses a leinamycin-type gene cluster, was identified from 14 strains of Streptomyces originating from the rhizosphere soil of Polygonatum cyrtonema Hua. The complete genome of Streptomyces sp. JL1001 was sequenced and analyzed. The genome of Streptomyces sp. JL1001 consists of a 7,943,495 bp chromosome with a 71.71% G+C content and 7315 protein-coding genes. We also identified 36 biosynthetic gene clusters (BGCs) for secondary metabolites in Streptomyces sp. JL1001. Twenty-seven BGCs had low (< 50%) or moderate (50-80%) similarity to other known secondary metabolite BGCs. In addition, a comparative analysis was conducted between the leinamycin-type gene cluster in Streptomyces sp. JL1001 and the biosynthetic gene clusters of leinamycin and largimycin. This study aims to provide a comprehensive analysis of the genomic features of rhizosphere Streptomyces sp. JL1001. It establishes the foundation for further investigation into experimental trials involving novel bioactive metabolites such as AT-less type I polyketides that have important potential applications in medicine and agriculture.

Polygonatum sibiricum polysaccharide regulation of gut microbiota: A viable approach to alleviate cognitive impairment.

Polygonatum sibiricum has anti-inflammatory effects and is one of the well-known functional foods. Polygonatum sibiricum polysaccharide (PSP), as a traditional medicinal and food homologous substance, can regulate the balance of intestinal flora and short chain fatty acid levels, reduce intestinal permeability and serum endotoxin levels, and inhibit the activation of astrocytes and microglia. It can significantly alleviate neurological diseases and improve cognitive impairment. Current evidence suggests that bidirectional communication between the central nervous system and the gastrointestinal tract may affect the human nervous system, cognition, and behavior through the gut-brain axis. This article provides a systematic review, detailing the biological activity of PSP, and explores the pathogenesis of gut microbiota signaling in cognitive impairment, providing a promising strategy for improving cognitive impairment.

Elucidating the interaction of rhizosphere microorganisms and environmental factors influencing the quality of Polygonatum kingianum Coll. et Hemsl.

Polygonatum kingianum Collett & Hemsl., is one of the most important traditional Chinese medicines in China. The purpose of this study is to investigate the relationship between herb quality and microbial-soil variables, while also examining the composition and structure of the rhizosphere microbial community in Polygonatum kingianum, the ultimate goal is to provide a scientific approach to enhancing the quality of P. kingianum. Illumina NovaSeq technology unlocks comprehensive genetic variation and biological functionality through high-throughput sequencing. And in this study it was used to analyze the rhizosphere microbial communities in the soils of five P. kingianum planting areas. Conventional techniques were used to measure the organic elements, pH, and organic matter content. The active ingredient content of P. kingianum was identified by High Performance Liquid Chromatography (HPLC) and Colorimetry. A total of 12,715 bacterial and 5487 fungal Operational Taxonomic Units (OTU) were obtained and taxonomically categorized into 81 and 7 different phyla. Proteobacteria, Bacteroidetes, and Acidobacteriae were the dominant bacterial phyla Ascomycota and Basidiomycota were the dominat fungal phyla. The key predictors for bacterial community structure included hydrolysable nitrogen and available potassium, while for altering fungal community structure, soil organic carbon content (OCC), total nitrogen content (TNC), and total potassium content (TPOC) were the main influencing factors. Bryobacter and Candidatus Solibacter may indirectly increase the polysaccharide content of P. kingianum, and can be developed as potential Plant Growth Promoting Rhizobacteria (PGPR). This study has confirmed the differences in the soil and microorganisms of different origins of P. kingianum, and their close association with its active ingredients. And it also broadens the idea of studying the link between plants and microorganisms.

Polygonati Rhizoma varieties and origins traceability based on multivariate data fusion combined with an artificial intelligence classification algorithm.

This study collected multidimensional feature data such as spectra, texture, and component contents of Polygonati Rhizoma from different origins and varieties (Polygonatum kingianum Coll. et Hemsl from Yunnan and Guizhou; Polygonatum cyrtonema Hua from Anhui and Jiangxi; Polygonatum sibiricum Red from Hunan). Multivariate statistical analysis was used to select 39 characteristic factors for distinguishing PR origins and 14 characteristic factors for discriminating PR varieties (VIP > 1 and P < 0.05). In addition, by combining multivariate statistical analysis with a deep belief network (DBN) classification algorithm, a novel artificial intelligence algorithm was developed and optimized. Compared to traditional discriminant analysis methods, the accuracy of this new approach was significantly improved, achieving a 100% discrimination rate for PR varieties and a 100% accuracy rate for tracing the origin of PR. This research provides a reference and data support for constructing intelligent algorithms based on multidimensional data fusion, to achieve food variety discrimination and origin tracing.

Integrative analyses of metabolome and transcriptome reveal the dynamic accumulation and regulatory network in rhizomes and fruits of Polygonatum cyrtonema Hua.

BACKGROUND: According to Chinese ancient books, both fruits and rhizomes of Polygonatum cyrtonema Hua have medicinal and edible values. Up to now, there is no report about the metabolite profiles and regulatory network in fruits and different year-old rhizomes of P. cyrtonema. RESULTS: In this study, we performed integrative analyses of metabolome and transcriptome to reveal the dynamic accumulation and regulatory network of fruits and different year-old rhizomes in P. cyrtonema. The relative content of phenolic acids, lignans and coumarins, flavonoids and alkaloids increased with growth years, while steroids and lipids decreased with it. In addition, the relative content of nucleotides and derivatives, flavonoids, organic acids, steroids and lipids in fruits were higher than rhizomes. Genes that might relate to the biosynthesis of polysaccharides, flavonoids, triterpene saponins and alkaloids biosynthesis were further analyzed by transcriptome analysis, including sacA, GMPP, PMM, CCoAOMT, CHI, ANR, CHS, DXS, GGPS, ZEP, CYP72A219 and so on, for their expressions were positively correlated with the relative content of the metabolites. Additionally, the correlation network in sugar and aromatic amino acids metabolites were constructed to further illustrate the biosynthesis of polysaccharides, flavonoids and alkaloids in P. cyrtonema, and some transcription factors (TFs) were screened, such as C2C2, MYB, bZIP, GRAS and NAC. CONCLUSIONS: This study can deepen our understanding of the accumulation patterns and molecular mechanism of the main compounds in P. cyrtonema, and provide reference for the standardize production of P. cyrtonema.

Zinc finger transcription factor ZFP1 is associated with growth, conidiation, osmoregulation, and virulence in the Polygonatum kingianum pathogen Fusarium oxysporum.

Rhizome rot is a destructive soil-borne disease of Polygonatum kingianum and adversely affects the yield and sustenance of the plant. Understanding how the causal fungus Fusarium oxysporum infects P. kingianum may suggest effective control measures against rhizome rot. In germinating conidia of infectious F. oxysporum, expression of the zinc finger transcription factor gene Zfp1, consisting of two C2H2 motifs, was up-regulated. To characterize the critical role of ZFP1, we generated independent deletion mutants (zfp1) and complemented one mutant with a transgenic copy of ZFP1 (zfp1 tZFP1). Mycelial growth and conidial production of zfp1 were slower than those of wild type (ZFP1) and zfp1 tZFP1. Additionally, a reduced inhibition of growth suggested zfp1 was less sensitive to conditions promoting cell wall and osmotic stresses than ZFP1 and zfp1 tZFP1. Furthermore pathogenicity tests suggested a critical role for growth of zfp1 in infected leaves and rhizomes of P. kingianum. Thus ZFP1 is important for mycelial growth, conidiation, osmoregulation, and pathogenicity in P. kingianum.

Structural characterization and hypoglycemic effect of polysaccharides of Polygonatum sibiricum.

Polygonatum sibiricum polysaccharide (PSP) was extracted and purified from raw material obtained from P. sibiricum. The structural features of PSP were investigated by Congo red, circular dichroism spectrum, high-performance gel permeation chromatography, scanning electron microscope, atomic force microscope, ultraviolet spectroscopy, and Fourier transform infrared spectroscopy analysis. In vitro simulations were conducted to investigate the kinetics of PSP enzyme inhibition. Moreover, a type II diabetes mouse model (T2DM) with streptozotocin-induced insulin resistance was established, and the indexes of lipid quadruple, insulin resistance index, oral glucose tolerance (OGTT), organ index, and pancreatic morphology of model mice were measured. The results showed that PSP mainly consists of monosaccharides, such as mannose, glucose, galactose, xylose, and arabinose. It also has a ß-glycosidic bond of a pyranose ring and an irregular reticulated aggregated structure with a triple helix. In vitro enzyme inhibition assays revealed that PSP acts as a reversible competitive inhibitor of α-glucosidase and α-amylase. Furthermore, PSP was found to reduce insulin resistance index, increase OGTT and serum insulin levels, decrease free fatty acid content to improve lipid metabolism, and lower glycated serum protein content to enhance glucose metabolism in T2DM mice, thereby leading to a reduction in blood glucose concentration. Additionally, PSP exhibited reparative effects on the damaged liver tissue cells and pancreatic tissue in T2DM mice. The experiment results provide a preliminary basis for the therapeutic mechanism of PSP about type II diabetes and a theoretical reference for application in food and pharmaceutical development.

Surface-Engineered Polygonatum Sibiricum Polysaccharide CaCO3 Microparticles as Novel Vaccine Adjuvants to Enhance Immune Response.

Micro- and nanoparticles delivery systems have been widely studied as vaccine adjuvants to enhance immunogenicity and sustain long-term immune responses. Polygonatum sibiricum polysaccharide (PSP) has been widely studied as an immunoregulator in improving immune responses. In this study, we synthesized and characterized cationic modified calcium carbonate (CaCO3) microparticles loaded with PSP (PEI-PSP-CaCO3, CTAB-PSP-CaCO3), studied the immune responses elicited by PEI-PSP-CaCO3 and CTAB-PSP-CaCO3 carrying ovalbumin (OVA). Our results demonstrated that PEI-PSP-CaCO3 significantly enhanced the secretion of IgG and cytokines (IL-4, IL-6, IFN-γ, and TNF-α) in vaccinated mice. Additionally, PEI-PSP-CaCO3 induced the activation of dendritic cells (DCs), T cells, and germinal center (GC) B cells in draining lymph nodes (dLNs). It also enhanced lymphocyte proliferation, increased the ratio of CD4+/CD8+ T cells, and elevated the frequency of CD3+ CD69+ T cells in spleen lymphocytes. Therefore, PEI-PSP-CaCO3 microparticles induced a stronger cellular and humoral immune response and could be potentially useful as a vaccine delivery and adjuvant system.

Fermentation of Polygonati Rhizoma aqueous extract using Lactiplantibacillus plantarum under the condition of eutrophication.

In this experiment, the eutrophication system was established by adding sucrose and yeast powder, and the pH and dissolved oxygen were measured in a bioreactor in real time to study the effect of aerobic environment on the fermentation process of Polygonati Rhizoma extract by Lactiplantibacillus plantarum. To further analyze metabolic changes, UPLC-Q-Exactive MS was used for metabolomic analysis and metabolic profiling. Multivariate analysis was performed using principal component analysis and Orthogonal projections to latent structures discriminant analysis. Finally, 313 differential metabolites were selected, 196 of which were annotated through database matching. After fermentation, the content of short-chain fatty acids, lactic acid, and their derivatives increased significantly, and there were 13 kinds and 4 kinds, respectively. Both compounds and their derivatives are beneficial to the intestinal flora. Consequently, incorporating L. plantarum into the aerobic fermentation process of Polygonati Rhizoma extract within the eutrophic system is potentially advantageous in enhancing the impact of its fermentation solution on the gut microbiota and its effects on human health. Our findings for this kind of edible and medicinal material research and development offer useful insights.

Multiomics reveals the ameliorating effect and underlying mechanism of aqueous extracts of polygonatum sibiricum rhizome on obesity and liver fat accumulation in high-fat diet-fed mice.

BACKGROUND: Polygonatum sibiricum polysaccharides protect against obesity and NAFLD. However, the potential effects of PS rhizome aqueous extracts (PSRwe) on adiposity and hepatic lipid accumulation remains unexplored. PURPOSE: Elucidating the impact and underlying mechanism of PSRwe on HFD-induced obesity and liver fat depostition. STUDY DESIGN: 56 male mice, aged eight weeks, were divided into seven groups: Positive, four doses of PSRwe, Model, and Control. HFD was fed for eight weeks, followed by alternate-day gavage of orlistat and PSRwe for an additional eight-week period. Integrative analysis encompassing multiomics, physiological and histopathological, and biochemical indexes was employed. METHODS: Body weight (BW); liver, fat and Lee's indexes; TC, TG, LDL-C, HDL-C, AST, ALT, FFA, leptin, and adiponectin in the liver and blood; TNFα, IL-6, and LPS in the colon, plasma, and liver; H&E, PAS and oil red O staining on adipose and liver samples were examined. OGTT and ITT were conducted The gut microbiome, microbial metabolome, colonic and liver transcriptome, plasma and liver metabolites were investigated. RESULTS: PSRwe at the dosage of 7.5 mg/kg demonstrated significant and consistent reduction in BW and hepatic fat deposition than orlistat. PSRwe significantly decreased TC, TG, LDL-C, LEP, FFA levels in blood and liver. PSRwe significantly enhanced the relative abundance of probiotics including Akkermansia muciniphila, Bifidobacterium pseudolongum, Lactobacillus reuteri, and metabolic pathways including glycolysis and fatty acids ß-oxidation. The 70 up-regulated microbial metabolites in PSRwe-treated mice mainly involved in nucleotides and amino acids metabolism, while 40 decreased metabolites primarily associated with lipid metabolism. The up-regulated colonic differentially expressed genes (DEGs) participate in JAK-STAT/PI3K-Akt/FoxO signaling pathway, serotonergic/cholinergic/glutamatergic synapses, while the down-regulated DEGs predominantly focused on fat absorption and transport. The up-regulated liver DEGs mainly concentrated on fatty acid oxidation and metabolism. Liver metabolisms revealed 131 differential metabolites, among which carnitine and oxidized lipids significantly increased in PSRwe-treated mice. In plasma, the 58 up-regulated metabolites mainly participate in co-factors/vitamins metabolism while 154 down-regulated ones in fatty acids biosynthesis. Comprehensive multiomics association analysis revealed significant associations between gut microbiota and colonic/liver gene expression, and suggested exogenous and endogenous betaine may be active compound in alleviating HFD-induced symptoms. CONCLUSION: PSRwe effectively mitigate HFD-induced obesity and hepatic steatosis by increasing beneficial bacteria, reducing colonic fat digestion/absorption, increasing hepatic lipid metabolism, and elevating betaine levels.

Integrative analysis of the transcriptome and metabolome provides insights into polysaccharide accumulation in Polygonatum odoratum (Mill.) Druce rhizome.

Background: Polygonatum odoratum (Mill.) Druce is a traditional Chinese herb that is widely cultivated in China. Polysaccharides are the major bioactive components in rhizome of P. odoratum and have many important biological functions. Methods: To better understand the regulatory mechanisms of polysaccharide accumulation in P. odoratum rhizomes, the rhizomes of two P. odoratum cultivars 'Y10' and 'Y11' with distinct differences in polysaccharide content were used for transcriptome and metabolome analyses, and the differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) were identified. Results: A total of 14,194 differentially expressed genes (DEGs) were identified, of which 6,689 DEGs were down-regulated in 'Y10' compared with those in 'Y11'. KEGG enrichment analysis of the down-regulated DEGs revealed a significant enrichment of 'starch and sucrose metabolism', and 'amino sugar and nucleotide sugar metabolism'. Meanwhile, 80 differentially accumulated metabolites (DAMs) were detected, of which 52 were significantly up-regulated in 'Y11' compared to those in 'Y10'. The up-regulated DAMs were significantly enriched in 'tropane, piperidine and pyridine alkaloid biosynthesis', 'pentose phosphate pathway' and 'ABC transporters'. The integrated metabolomic and transcriptomic analysis have revealed that four DAMs, glucose, beta-D-fructose 6-phosphate, maltose and 3-beta-D-galactosyl-sn-glycerol were significantly enriched for polysaccharide accumulation, which may be regulated by 17 DEGs, including UTP-glucose-1-phosphate uridylyltransferase (UGP2), hexokinase (HK), sucrose synthase (SUS), and UDP-glucose 6-dehydrogenase (UGDH). Furthermore, 8 DEGs (sacA, HK, scrK, GPI) were identified as candidate genes for the accumulation of glucose and beta-D-fructose 6-phosphate in the proposed polysaccharide biosynthetic pathways, and these two metabolites were significantly associated with the expression levels of 13 transcription factors including C3H, FAR1, bHLH and ERF. This study provided comprehensive information on polysaccharide accumulation and laid the foundation for elucidating the molecular mechanisms of medicinal quality formation in P. odoratum rhizomes.

Combined Metabolomics and Transcriptomics Analysis of the Distribution of Flavonoids in the Fibrous Root and Taproot of Polygonatum kingianum Coll.et Hemsl.

Polygonati rhizoma, known for its distinct yellow rhizomes, is a common therapeutic and culinary plant in Far East Asia. The hue of medicinal plants is closely tied to the flavonoid biosynthesis and content levels. In this research, the fibrous root and taproot of Polygonatum kingianum Coll.et Hemsl. were studied to explore the secondary metabolite expression and flavonoid biosynthesis mechanisms using transcriptomics and metabolomics. Metabolic analysis identified that the differentially accumulated metabolites (DAMs) in the fibrous root and taproot were predominantly flavonoids, steroids, alkaloids, and phenolic acids. Overall, 200 flavonoids were identified in P. kingianum Coll.et Hemsl., with 170 exhibiting variances between the fibrous root and taproot. The transcriptome analysis revealed that a total of 289 unigenes encoding 32 enzymes were annotated into four flavonoid biosynthesis pathways, which include phenylpropanoid biosynthesis pathway, flavonoid biosynthesis pathway, isoflavonoid biosynthesis pathway, and flavone and flavonol biosynthesis pathway. The integration of transcriptomic and metabolomic data elucidated that the 76 differentially expressed genes (DEGs) encoding 13 enzyme genes (HCT, CCOMT, C4H, C3'H, CHI, PGT1, FLS, F3'H, CHS, ANR, DFR, F3'5'H, and LAR) and 15 DAMs preferred to be regulated in the flavonoid biosynthesis pathway. The expression of 10 DEGs was validated by qRT-PCR, agreeing with the same results by RNA-Seq. These findings shed light into the biosynthesis of secondary metabolites in P. kingianum Coll.et Hemsl., offering valuable information for the sustainable utilization and enhancement of this plant species.

Polygonatum sibiricum polysaccharides protect against knee osteoarthritis by inhibiting the TLR2/NF-κB signaling pathway in vivo and in vitro.

Polygonatum sibiricum polysaccharides (PSP), the primary constituent of Polygonatum sibiricum, have been shown to exhibit a wide range of pharmacological effects, but their impact on osteoarthritis (OA) remains unclear. The objective of this study was to investigate the protective effects of PSP against OA and to elucidate its underlying molecular mechanism. In our in vitro experiments, PSP not only inhibited the IL-1ß-induced inflammatory responses and the nuclear factor kappa-B (NF-κB) signaling pathway in chondrocytes but also regulated the cartilage matrix metabolism. In addition, we detected 394 significantly differentially expressed genes through RNA-seq analysis on PSP-intervened chondrocytes, and the toll-like receptor 2 (TLR2) was identified as the most important feature by functional network analysis and qRT-PCR. It was also revealed that PSP treatment significantly reversed the IL-1-induced up-regulation of TLR2 expression in chondrocytes, while TLR2 overexpression partially inhibited the regulatory effects of PSP on inflammation, NF-κB signaling pathway and matrix metabolism. In our in vivo experiments, PSP treatment alleviated the development of destabilization of medial meniscus (DMM)-induced OA in mouse knee joints, inhibited the DMM-induced activation of the TLR2/NF-κB signaling pathway in mouse knee joint cartilage, and reduced the serum levels of inflammatory cytokines. In conclusion, PSP exerts its anti-inflammatory, matrix synthesis-promoting and matrix catabolism-suppressing effects in knee OA by inhibiting the TLR2/NF-κB signaling pathway, suggesting that PSP may be potentially targeted as a novel all-natural, low-toxicity drug for OA prevention and treatment.

Polygonatum polysaccharide ameliorates D-galactose-induced cognitive dysfunction in aging rats by inhibiting ferroptosis through activation of Nrf2.

CONTEXT: Aging is a major risk factor for various neurodegenerative diseases, and ferroptosis has been identified as an important mode of cell death during accelerated aging. As the main component of the edible plant YuZhu in China, Polygonatum polysaccharide (POP) is an important natural compound with anti-aging properties. OBJECTIVE: To evaluate the anti-aging effects of POP and the underlying molecular mechanisms involved and to evaluate the overall anti-aging effects of POP on cognitive impairment due to accelerated aging. MATERIALS AND METHODS: A D-galactose (D-gal)-induced accelerated aging rat model was established to evaluate the anti-aging effects of POP and the underlying molecular mechanisms involved. In turn, Morris water maze and open field experiments were used to evaluate the anti-aging effects of POP on cognitive impairment due to accelerated aging. RESULTS: The mechanism by which POP affects nuclear factor E2-related factor 2 (Nrf2), an essential transcription factor, was confirmed. POP significantly improved d-gal-induced cognitive dysfunction in treated model rats, which exhibited reduced pathological changes in the hippocampus, reduced latency of the water maze platform, and increased exploration time in the central area in the open field experiment compared to those of untreated model rats. Furthermore, POP intervention downregulated ferroptosis-related proteins and upregulated Nrf2 expression, and selective inhibition of Nrf2 eliminated the ability of POP to reduce ferroptosis. CONCLUSIONS: POP is a natural ingredient with therapeutic potential due to its ability to alleviate aging by activating Nrf2, inhibiting ferroptosis, and alleviating cognitive dysfunction.

Effect of ultrasonic degradation on the physicochemical characteristics, GLP-1 secretion, and antioxidant capacity of Polygonatum cyrtonema polysaccharide.

This study aimed to evaluate the influence of ultrasonic degradation on the physicochemical and biological characteristics of Polygonatum cyrtonema polysaccharide (PCP, 8.59 kDa). PCP was subjected to ultrasonic treatment for 8, 16, and 24 h and yielded the degraded fractions PCP-8, PCP-16, and PCP-24 (5.06, 4.13, and 3.69 kDa), respectively. Compared with the intact PCP, PCP-8, PCP-16 and PCP-24 had a reduced particle size (decrements of 28.03 %, 46.15 % and 62.54 %, respectively). Although ultrasonic degradation did not alter the primary structure of PCP, its triple helical and superficial structures were disrupted, with degraded fractions demonstrating reduced thermal stability and apparent viscosities compared with those of the intact PCP. Furthermore, the functional properties of the degraded fractions were different. PCP-16 most favourably affected GLP-1 secretion, while PCP-8 and PCP-24 exhibited the strongest antioxidant and enzyme inhibitory activities, respectively. Hence, controlled ultrasound irradiation is an appealing approach for partially degrading PCP and enhancing its bioactivity as a functional agent.

Differentiation of Polygonatum Cyrtonema Hua from Different Geographical Origins by Near-Infrared Spectroscopy with Chemometrics.

BACKGROUND: The identification of the geographical origin of Polygonatum cyrtonema Hua is of particular importance because the quality and market value of Polygonatum cyrtonema Hua from different production areas are highly variable due to differences in the growing environment and climatic conditions. OBJECTIVE: This study utilized near-infrared spectra (NIR) of Polygonatum cyrtonema Hua (n = 400) to develop qualitative models for effective differentiation of Polygonatum cyrtonema Hua from various regions. METHODS: The models were produced under different conditions to distinguish the origins distinctly. Ten preprocessing methods have been used to preprocess the original spectra (OS) and to select the most optimal spectral preprocessing method. Principal component analysis (PCA), partial least-squares discriminant analysis (PLS-DA), and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to determine appropriate models. For simplicity, the pretreated full spectrum was calculated by different wavelength selection methods, and the four most significant variables were selected as discriminant indicator variables. RESULTS: The results show that Polygonatum cyrtonema Hua from different regions can be effectively distinguished using spectra from a series of samples analyzed by OPLS-DA. The accuracy of the OPLS-DA model is also satisfactory, with a good differentiation rate. CONCLUSION: The study findings indicate the feasibility of using spectroscopy in combination with multivariate analysis to identify the geographical origins of Polygonatum cyrtonema Hua. HIGHLIGHTS: The utilization of NIR spectroscopy combined with chemometrics exhibits high efficacy in discerning the provenance of herbal medicines and foods, thereby facilitating QA measures.

Integrated Metabolomics and Transcriptomics Analysis of Flavonoid Biosynthesis Pathway in Polygonatum cyrtonema Hua.

Flavonoids, a class of phenolic compounds, are one of the main functional components and have a wide range of molecular structures and biological activities in Polygonatum. A few of them, including homoisoflavonoids, chalcones, isoflavones, and flavones, were identified in Polygonatum and displayed a wide range of powerful biological activities, such as anti-cancer, anti-viral, and blood sugar regulation. However, few studies have systematically been published on the flavonoid biosynthesis pathway in Polygonatum cyrtonema Hua. Therefore, in the present study, a combined transcriptome and metabolome analysis was performed on the leaf, stem, rhizome, and root tissues of P. cyrtonema to uncover the synthesis pathway of flavonoids and to identify key regulatory genes. Flavonoid-targeted metabolomics detected a total of 65 active substances from four different tissues, among which 49 substances were first study to identify in Polygonatum, and 38 substances were flavonoids. A total of 19 differentially accumulated metabolites (DAMs) (five flavonols, three flavones, two dihydrochalcones, two flavanones, one flavanol, five phenylpropanoids, and one coumarin) were finally screened by KEGG enrichment analysis. Transcriptome analysis indicated that a total of 222 unigenes encoding 28 enzymes were annotated into three flavonoid biosynthesis pathways, which were "phenylpropanoid biosynthesis", "flavonoid biosynthesis", and "flavone and flavonol biosynthesis". The combined analysis of the metabolome and transcriptome revealed that 37 differentially expressed genes (DEGs) encoding 11 enzymes (C4H, PAL, 4CL, CHS, CHI, F3H, DFR, LAR, ANR, FNS, FLS) and 19 DAMs were more likely to be regulated in the flavonoid biosynthesis pathway. The expression of 11 DEGs was validated by qRT-PCR, resulting in good agreement with the RNA-Seq. Our studies provide a theoretical basis for further elucidating the flavonoid biosynthesis pathway in Polygonatum.

Structural Characterization of Polygonatum Cyrtonema Polysaccharide and Its Immunomodulatory Effects on Macrophages.

A neutral Polygonatum cyrtonema polysaccharide (NPCP) was isolated and purified from Polygonatum cyrtonema by various chromatographic techniques, including DEAE-52 and Sephadex-G100 chromatography. The structure of NPCP was characterized by HPLC, HPGPC, GC-MS, FT-IR, NMR, and SEM. Results showed that NPCP is composed of glucose (55.4%) and galactose (44.6%) with a molecular weight of 3.2 kDa, and the sugar chain of NPCP was →1)-α-D-Glc-(4→1)-ß-D-Gal-(3→. In vitro bioactivity experiments demonstrated that NPCP significantly enhanced macrophages proliferation and phagocytosis while inhibiting the M1 polarization induced by LPS as well as the M2 polarization induced by IL-4 and IL-13 in macrophages. Additionally, NPCP suppressed the secretion of IL-6 and TNF-α in both M1 and M2 cells but promoted the secretion of IL-10. These results suggest that NPCP could serve as an immunomodulatory agent with potential applications in anti-inflammatory therapy.