Physiological and transcriptomic comparisons shed light on the cold stress response mechanisms of Dendrobium spp.

BACKGROUND: Dendrobium spp. comprise a group of tropical orchids with ornamental and medicinal value. Dendrobium spp. are sensitive to low temperature, and the underlying cold response regulatory mechanisms in this group are unclear. To understand how these plants respond to cold stress, we compared the transcriptomic responses of the cold-tolerant cultivar 'Hongxing' (HX) and the cold-sensitive cultivar 'Sonia Hiasakul' (SH) to cold stress. RESULTS: Chemometric results showed that the physiological response of SH in the later stages of cold stress is similar to that of HX throughout the cold treatment. Orthogonal partial least squares discriminant analysis (OPLS-DA) revealed that soluble protein content and peroxidase activity are key physiological parameters for assessing the cold tolerance of these two Dendrobium spp. cultivars. Additionally, weighted gene co-expression network analysis (WGCNA) results showed that many cold response genes and metabolic pathways significantly associated with the physiological indices were enriched in the 12 detected modules. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and gene ontology (GO) enrichment analyses of the 105 hub genes showed that Dendrobium spp. adapt to cold stress by regulating signal transduction, phytohormones, transcription factors, protein translation and modification, functional proteins, biosynthesis and metabolism, cell structure, light, and the circadian clock. Hub genes of the cold stress response network included the remorin gene pp34, the abscisic acid signaling pathway-related genes PROTEIN PHOSPATASE 2 C (PP2C), SNF1-RELATED PROTEIN KINASE 2 (SnRK2), ABRE-BINDING FACTOR 1 (ABF1) and SKI-INTERACTING PROTEIN 17 (SKIP17), the Ca2+ signaling-related GTP diphosphokinase gene CRSH1, the carbohydrate-related gene STARCH SYNTHASE 2 (SS2), the cell wall biosynthesis gene CINNAMYL ALCOHOL DEHYDROGENASE (CAD7), and the endocytosis-related gene VACUOLAR PROTEIN SORTING-ASSOCIATED PROTEIN 52 A (VPS52A). CONCLUSIONS: The cold-responsive genes and metabolic pathways of Dendrobium spp. revealed in this study provide important insight to enable the genetic enhancement of cold tolerance in Dendrobium spp., and to facilitate cold tolerance breeding in related plants.

DhuFAP: a platform for gene functional analysis in Dendrobium huoshanense.

BACKGROUND: Dendrobium huoshanense, a traditional medicinal and food plant, has a rich history of use. Recently, its genome was decoded, offering valuable insights into gene function. However, there is no comprehensive gene functional analysis platform for D. huoshanense. RESULT: To address this, we created a platform for gene function analysis and comparison in D. huoshanense (DhuFAP). Using 69 RNA-seq samples, we constructed a gene co-expression network and annotated D. huoshanense genes by aligning sequences with public protein databases. Our platform contained tools like Blast, gene set enrichment analysis, heatmap analysis, sequence extraction, and JBrowse. Analysis revealed co-expression of transcription factors (C2H2, GRAS, NAC) with genes encoding key enzymes in alkaloid biosynthesis. We also showcased the reliability and applicability of our platform using Chalcone synthases (CHS). CONCLUSION: DhuFAP ( www.gzybioinformatics.cn/DhuFAP ) and its suite of tools represent an accessible and invaluable resource for researchers, enabling the exploration of functional information pertaining to D. huoshanense genes. This platform stands poised to facilitate significant biological discoveries in this domain.

Optimizing nutrient solution for vegetative growth of Dendrobium Tubtim Siam and Phalaenopsis Taisuco Swan through plant tissue nutrient balance estimation.

BACKGROUND: Orchids are grown without soil in many regions of the world, but there is a lack of studies to define the balanced and adequate nutrient solution for their cultivation, mainly in the vegetative growth phase. Therefore, this paper aims to evaluate the optimal concentration of the nutrient solution based on the proposal by Hoagland and Arnon (1950) in the vegetative growth phase capable of increasing the nutrient contents, growth, and dry matter production of Dendrobium Tubtim Siam and Phalaenopsis Taisuco Swan. In addition, this paper aims to estimate a new nutrient solution from the optimal nutrient contents in the dry matter of these orchid species to be used in the vegetative growth phase. RESULTS: Nutrient contents, growth, and dry matter production increased as the nutrient solution concentration increased up to an average concentration of 62 and 77% for D. Tubtim Siam and P. Taisuco Swan, respectively. We found that the Hoagland and Arnon solution presented a group of nutrients with concentrations above the requirement for P. Taisuco Swan (nitrogen, phosphor, calcium, and sulfur) and D. Tubtim Siam (phosphor, calcium, magnesium, and sulfur), while other nutrients in the solution did not meet the nutritional demand of these orchid species, inducing nutritional imbalance in the vegetative growth phase. CONCLUSION: We conclude that using a balanced nutrient solution created specifically for each orchid species in vegetative growth might favor their sustainable cultivation by optimizing the use of nutrients in the growing medium.

DcERF109 regulates shoot branching by participating in strigolactone signal transduction in Dendrobium catenatum.

Shoot branching fundamentally influences plant architecture and agricultural yield. However, research on shoot branching in Dendrobium catenatum, an endangered medicinal plant in China, remains limited. In this study, we identified a transcription factor DcERF109 as a key player in shoot branching by regulating the expression of strigolactone (SL) receptors DWARF 14 (D14)/ DECREASED APICAL DOMINANCE 2 (DAD2). The treatment of D. catenatum seedlings with GR24rac/TIS108 revealed that SL can significantly repress the shoot branching in D. catenatum. The expression of DcERF109 in multi-branched seedlings is significantly higher than that of single-branched seedlings. Ectopic expression in Arabidopsis thaliana demonstrated that overexpression of DcERF109 resulted in significant shoot branches increasing and dwarfing. Molecular and biochemical assays demonstrated that DcERF109 can directly bind to the promoters of AtD14 and DcDAD2.2 to inhibit their expression, thereby positively regulating shoot branching. Inhibition of DcERF109 by virus-induced gene silencing (VIGS) resulted in decreased shoot branching and improved DcDAD2.2 expression. Moreover, overexpression of DpERF109 in A. thaliana, the homologous gene of DcERF109 in Dendrobium primulinum, showed similar phenotypes to DcERF109 in shoot branch and plant height. Collectively, these findings shed new insights into the regulation of plant shoot branching and provide a theoretical basis for improving the yield of D. catenatum.

Structure characteristics, protective effect and mechanisms of ethanol-fractional polysaccharides from Dendrobium officinale on acute ethanol-induced gastritis.

Gastritis is a common disease characterized by gastric ulcers and severe bleeding. Excessive daily alcohol consumption can cause acute gastritis, impacting individuals' quality of life. This study aims to explore the protective effects of different ethanol-fractional polysaccharides of Dendrobium officinale (EPDO) on acute alcohol-induced gastric injury in vivo. Results showed that EPDO-80, identified as a ß-glucan, exhibited significant anti-inflammatory properties in pathology. It could reduce the area of gastric mucosal injury and cell infiltration. EPDO-80 had a dose-effect relationship in reducing the levels of malondialdehyde and cyclooxygenase-2 and decreasing the levels of inflammation mediators such as tumor necrosis factor α. More extensively, EPDO-80 could inhibit the activation of the TNFR/IκB/NF-κB signaling pathway, reducing the production of TNF-α mRNA and cell apoptosis in organs. Conversely, EPDO-80 could promote changes in the gut microbiota structure. These findings suggest that EPDO-80 could have great potential in limiting oxidative stress and inflammation mediated by inhibiting the NF-κB signaling pathway, which is highly related to its ß-glucan structure and functions in gut microbiota.

[Identification and expression profiling of SAPK gene family members in Dendrobium officinale].

To investigate the potential roles of stress-activated protein kinase (SAPK) gene family members in Dendrobium officinale, we employed multiple bioinformatics methods to identify the members of this family. The physicochemical properties, chromosomal localization, phylogenetic relationship, gene structure, and cis-acting elements of each D. officinale SAPK (DoSAPK) member were analyzed. In addition, their expression profiles in different tissues and under the low-temperature or salt stress treatment were determined by real-time fluorescence quantitative PCR. The results showed that D. officinale carried eight DoSAPK family members, which belonged to three groups (groups Ⅰ, Ⅱ, and Ⅲ). These genes were located on seven chromosomes, and there were two pairs of genes with replication. The DoSAPK members within the same group had similar gene structures, conserved motifs, and secondary structures. The cis-acting elements in the promoter regions of DoSAPK genes included abundant hormone and stress response elements. DoSAPK family members presented tissue-specific expression in D. officinale. Furthermore, they were differentially expressed under the low-temperature or salt stress treatment, which suggested that they might be involved in the responses to low-temperature and salt stress. Intriguingly, DoSAPK1 might play a role in the abiotic stress responses. The results laid a foundation for in-depth study of the members and roles of the DoSAPK gene family.

Mechanism of Dendrobium Nobile Polysaccharide Inhibition of Ferroptosis in Rats with Spinal Cord Injury.

BACKGROUND: It has been reported that ferroptosis participates in the pathophysiological mechanism of spinal cord injury (SCI). Our preliminary experiments verified that dendrobium nobile polysaccharide (DNP) improved the behavioral function of SCI rats. Therefore, the purpose of this study was to examine the role of DNP on ferroptosis and its neuroprotective mechanism in SCI rats. METHODS: Adult female sprague dawley (SD) rats were exposed to SCI by Allen's method, followed by an intragastric injection of 100 mg/kg DNP per day for 2 weeks. Behavioral features were verified by the Basso-Beattie-Bresnahan (BBB) scale and footprint evaluation. Iron content and glutathione (GSH) were assessed spectrophotometrically. Mitochondrial morphology was examined by transmission electron microscopy. The expression of ferroptosis-related genes, including System Xc- light chain (xCT), G-rich RNA sequence binding Factor 1 (GRSF1) and glutathione peroxidase 4 (Gpx4), was examined by real-time polymerase chain reaction (PCR) and western blot. The spinal cavity was defined using hematoxylin-eosin (HE) staining, and neuronal modifications were detected by immunofluorescence. RESULTS: Compared with the SCI group, the BBB score of rats in the DNP group increased at 7 d, 14 d, 21 d, and 28 d. The differences between the two groups were statistically significant. At 12 h post-injury the iron content began to decrease. At 24 h post-injury the iron content decreased significantly in the DNP group. The morphological changes of the mitochondrial crest and membrane in the DNP group were ameliorated within 24 h. Compared with the sham group, the expression of xCT, GSH, Gpx4, and GRSF1 were significantly reduced after SCI. After DNP treatment, the expression of xCT, Gpx4, and GSH were higher. The tissue cavity area was significantly reduced and the amount of NeuN+ cells was increased in the DNP group at 14 d and 28 d after SCI. CONCLUSIONS: DNP facilitated the post-injury recovery in SCI rats via the inhibition of ferroptosis.

Effects of Ethanol Concentrations on Primary Structural and Bioactive Characteristics of Dendrobium officinale Polysaccharides.

Ethanol fractional precipitation can initially separate polysaccharides according to the structure, which exhibits strong correlation with the biological activities. This study aimed to investigate the impact of varying ethanol concentrations on the structural characteristics, and the antitumor and antioxidant activities of polysaccharides derived from Dendrobium officinale through ethanol fractional precipitation, as well as their internal relationships. The polysaccharides acquired by absolute alcohol additions at a final liquor-ethanol volume ratio of 1:1, 1:2, and 1:4 were named DOP-1, DOP-2, and DOP-4, and the supernatant was named DOP-S. The results of the structural analysis revealed that the increase in ethanol concentrations resulted in a reduction in the molecular weights and the acetylation degree of the polysaccharides, as well as a decrease in mannose content and an increase in glucose content. In vitro experiments demonstrated that DOP-S exhibited optimal antitumor and antioxidant activities. Animal experiments further confirmed that DOP-S suppressed the growth of solid tumors significantly, enhanced lymphocytes, mediated immune ability, and improved the activity of antioxidant enzymes. These findings would establish a theoretical foundation and provide technical support for further advances and applications of polysaccharides derived from D. officinale in the fields of food and medicine.

Metabolites rapid-annotation in mice by comprehensive method of virtual polygons and Kendric mass loss filtering: A case study of Dendrobium nobile Lindl.

With significant advancements in high-resolution mass spectrometry, there has been a substantial increase in the amount of chemical component data acquired from natural products. Therefore, the rapid and efficient extraction of valuable mass spectral information from large volumes of high-resolution mass spectrometry data holds crucial significance. This study illustrates a targeted annotation of the metabolic products of alkaloid and sesquiterpene components from Dendrobium nobile (D. nobile) aqueous extract in mice serum through the integration of an in-houses database, R programming, a virtual metabolic product library, polygonal mass defect filtering, and Kendrick mass defect strategies. The research process involved initially establishing a library of alkaloids and sesquiterpenes components and simulating 71 potential metabolic reactions within the organism using R programming, thus creating a virtual metabolic product database. Subsequently, employing the virtual metabolic product library allowed for polygonal mass defect filtering, rapidly screening 1705 potential metabolites of alkaloids and 3044 potential metabolites of sesquiterpenes in the serum. Furthermore, based on the chemical composition database of D. nobile and online mass spectrometry databases, 95 compounds, including alkaloids, sesquiterpenes, and endogenous components, were characterized. Finally, utilizing Kendrick mass defect analysis in conjunction with known alkaloids and sesquiterpenes targeted screening of 209 demethylation, methylation, and oxidation products in phase I metabolism, and 146 glucuronidation and glutathione conjugation products in phase II metabolism. This study provides valuable insights for the rapid and accurate annotation of chemical components and their metabolites in vivo within natural products.

Dendrobium officinale regulate lipid metabolism in diabetic mouse liver via PPAR-RXR signaling pathway: Evidence from an integrated multi-omics analysis.

Dendrobium officinale (DEN) is recognized as a kind of functional food that can effectively ameliorate endocrine and metabolic disruptions. This study delved into the pharmacological mechanism of DEN on hepatic lipotoxicity associated with Type II diabetes mellitus (T2DM). In vivo study experiments on db/db mice indicated that DEN treatment notably enhanced liver function, decreased blood lipid levels, and improved insulin sensitivity. Non-targeted metabolomics analysis revealed that DEN significantly ameliorated metabolism pathways, including lipoic acid, linoleic acid, bile secretion, and the alanine/aspartate/glutamate metabolism, as well as taurine and hypotaurine metabolism. Transcriptomics analysis demonstrated DEN treatment could modulate the expression of genes such as Cpt1b, Scd1, G6pc2, Fos, Adrb2, Atp2a1, Ppp1r1b, and Cyp7a1. Furthermore, Proteomics analysis indicated that the beneficial effect of DEN on lipid metabolism was linked to pathways like AMPK and PPAR signaling. The integrative analysis of multi-omics revealed that the PPAR-RXR signaling was critical to the therapeutic effect of DEN on T2DM-induced fatty liver. Additionally, in vitro study on AML-12 cells confirmed that DEN counteract PA-induced lipid accumulation by activating the PPAR-RXR pathway. Overall, these findings suggested that DEN exhibited the potential to mitigate T2DM-induced hepatic lipo-toxicity and manage lipid imbalances in T2DM.

Integrated component identification, network pharmacology, and experimental verification revealed mechanism of Dendrobium officinale Kimura et Migo against lung cancer.

BACKGROUND: Dendrobium officinale Kimura et Migo (DO), a valuable Chinese herbal medicine, has been reported to exhibit potential effects in the prevention and treatment of lung cancer. However, its material basis and mechanism of action have not been comprehensively analyzed. PURPOSE: The objective of this study was to preliminarily elucidate the active components and pharmacological mechanisms of DO in treating lung cancer, according to UPLC-Q/TOF-MS, HPAEC-PAD, network pharmacology, molecular docking, and experimental verification. METHODS: The chemical components of DO were identified via UPLC-Q/TOF-MS, while the monosaccharide composition of Dendrobium officinale polysaccharide (DOP) was determined by HPAEC-PAD. The prospective active constituents of DO as well as their respective targets were predicted in the combined database of Swiss ADME and Swiss Target Prediction. Relevant disease targets for lung cancer were searched in OMIM, TTD, and Genecards databases. Further, the active compounds and potential core targets of DO against lung cancer were found by the C-T-D network and the PPI network, respectively. The core targets were then subjected to enrichment analysis in the Metascape database. The main active compounds were molecularly docked to the core targets and visualized. Finally, the viability of A549 cells and the relative quantity of associated proteins within the major signaling pathway were detected. RESULTS: 249 ingredients were identified from DO, including 39 flavonoids, 39 bibenzyls, 50 organic acids, 8 phenanthrenes, 27 phenylpropanoids, 17 alkaloids, 17 amino acids and their derivatives, 7 monosaccharides, and 45 others. Here, 50 main active compounds with high degree values were attained through the C-T-D network, mainly consisting of bibenzyls and monosaccharides. Based on the PPI network analysis, 10 core targets were further predicted, including HSP90AA1, SRC, ESR1, CREBBP, MAPK3, AKT1, PIK3R1, PIK3CA, HIF1A, and HDAC1. The results of the enrichment analysis and molecular docking indicated a close association between the therapeutic mechanism of DO and the PI3K-Akt signaling pathway. It was confirmed that the bibenzyl extract and erianin could inhibit the multiplication of A549 cells in vitro. Furthermore, erianin was found to down-regulate the relative expressions of p-AKT and p-PI3K proteins within the PI3K-Akt signaling pathway. CONCLUSIONS: This study predicted that DO could treat lung cancer through various components, multiple targets, and diverse pathways. Bibenzyls from DO might exert anti-lung cancer activity by inhibiting cancer cell proliferation and modulating the PI3K-Akt signaling pathway. A fundamental reference for further studies and clinical therapy was given by the above data.

Drought Stress Induced Different Response Mechanisms in Three Dendrobium Species under Different Photosynthetic Pathways.

Many Dendrobium species, which hold a high status and value in traditional Chinese medicine, grow on barks and rocks in the wild, often encountering harsh environments and facing droughts. However, the molecular mechanisms underlying the shift in the photosynthetic pathway induced by drought remain unclear. To address this issue, three Dendrobium species with different photosynthetic pathways were selected for sequencing and transcriptome data analysis after drought treatment. The findings included 134.43 GB of sequencing data, with numerous Differentially Expressed Genes (DEGs) exhibiting different response mechanisms under drought stress. Gene Ontology (GO)-KEGG-based enrichment analysis of DEGs revealed that metabolic pathways contributed to drought tolerance and alterations in photosynthetic pathways. Phosphoenolpyruvate Carboxylase (PEPC) was subjected to phylogenetic tree construction, sequence alignment, and domain analysis. Under drought stress, variations were observed in the PEPC gene structure and expression among different Dendrobium species; the upregulation of Dc_gene2609 expression may be caused by dof-miR-384, which resulted in the shift from C3 photosynthesis to CAM, thereby improving drought tolerance in Dendrobium. This study revealed the expression patterns and roles of PEPC genes in enhancing plant drought tolerance and will provide an important basis for in-depth research on Dendrobium's adaptation mechanisms in arid environments.

[Cloning and functional analysis of flavanone synthase â ¡ from Dendrobium huoshanense].

Flavonoid C-glycosides are a class of natural products that are widely involved in plant defense responses and have diverse pharmacological activities. They are also important active ingredients of Dendrobium huoshanense. Flavanone synthase Ⅱ has been proven to be a key enzyme in the synthesis pathway of flavonoid C-glycosides in plants, and their catalytic product 2-hydroxyflavanone is the precursor compound for the synthesis of various reported flavonoid C-glycosides. In this study, based on the reported amino acid sequence of flavanone synthase Ⅱ, a flavanone synthase Ⅱ gene(DhuFNSⅡ) was screened and verified from the constructed D. huoshanense genome localization database. Functional validation of the enzyme showed that it could in vitro catalyze naringenin and pinocembrin to produce apigenin and chrysin, respectively. The open reading frame(ORF) of DhuFNSⅡ was 1 644 bp in length, encoding 547 amino acids. Subcellular localization showed that the protein was localized on the endoplasmic reticulum. RT-qPCR results showed that DhuFNSⅡ had the highest expression in stems, followed by leaves and roots. The expression levels of DhuFNSⅡ and other target genes in various tissues of D. huoshanense were significantly up-regulated after four kinds of abiotic stresses commonly encountered in the growth process, but the extent of up-regulation varied among treatment groups, with drought and cold stress having more significant effects on gene expression levels. Through the identification and functional analysis of DhuFNSⅡ, this study is expected to contribute to the elucidation of the molecular mechanism of the formation of quality metabolites of D. huoshanense, flavonoid C-glycosides, and provide a reference for its quality formation and scientific cultivation.

Anticipation and Verification of Dendrobium-Derived Nanovesicles for Skin Wound Healing Targets, Predicated Upon Immune Infiltration and Senescence.

Background: Dendrobium, with profound botanical importance, reveals a rich composition of bioactive compounds, including polysaccharides, flavonoids, alkaloids, and diverse amino acids, holding promise for skin regeneration. However, the precise mechanism remains elusive. Seeking a potent natural remedy for wound healing, exocyst vesicles were successfully isolated from Dendrobium. Aims of the Study: This investigation aimed to employ bioinformatics and in vivo experiments to elucidate target genes of Dendrobium-derived nanovesicles in skin wound healing, focusing on immune infiltration and senescence characteristics. Materials and Methods: C57 mice experienced facilitated wound healing through Dendrobium-derived nanovesicles (DDNVs). Bioinformatics analysis and GEO database mining identified crucial genes by intersecting immune-related, senescence-related, and PANoptosis-associated genes. The identified genes underwent in vivo validation. Results: DDNVs remarkably accelerated skin wound healing in C57 mice. Bioinformatics analysis revealed abnormal expression patterns of immune-related, senescence-related, and pan-apoptosis-related genes, highlighting an overexpressed IL-1ß and downregulated IL-18 in the model group, Exploration of signaling pathways included IL-17, NF-kappa B, NOD-like receptor, and Toll-like receptor pathways. In vivo experiments confirmed DDNVs' efficacy in suppressing IL-1ß expression, enhancing wound healing. Conclusion: Plant-derived nanovesicles (PDNV) emerged as a natural, reliable, and productive approach to wound healing. DDNVs uptake by mouse skin tissues, labeled with a fluorescent dye, led to enhanced wound healing in C57 mice. Notably, IL-1ß overexpression in immune cells and genes played a key role. DDNVs intervention effectively suppressed IL-1ß expression, accelerating skin wound tissue repair.

Dendrobium officinale Polysaccharides as a Natural Functional Component for Acetic-Acid-Induced Gastric Ulcers in Rats.

Dendrobium officinale is an important edible and medicinal plant, with the Dendrobium officinale polysaccharide (DOP) being its primary active constituent, known for its diverse biological activities. In this study, DOP was extracted and characterized for its structural properties. The potential of DOP to ameliorate gastric ulcers (GUs) was investigated using an acetic-acid-induced GU model in rats. The results demonstrated that DOP exerted a multifaceted protective effect against GU, mitigating the deleterious impact on food intake and body weight in rats. DOP exhibited its protective action by attenuating cellular damage attributed to oxidative stress and inflammatory reactions mediated by enhanced activities of SOD, GSH, and GSH-PX, coupled with a downregulation in the expression of pro-inflammatory cytokines, including IL-1ß, IL-6, and TNF-α. Furthermore, DOP effectively inhibited apoptosis in gastric mucosa cells of acetic-acid-induced GU rat models and facilitated the self-repair of damaged tissues. Remarkably, the DOP-200 and DOP-400 groups outperformed omeprazole in reducing the expression of IL-6 and malondialdehyde (MDA) in tissues, as well as IL-1ß, IL-6, and TNF-α in serum. These groups also exhibited an improved expression of SOD in tissues and SOD, GSH, and GSH-PX in serum. A Western blot analysis of gastric mucosa demonstrated that the DOP-200 and DOP-400 groups significantly reduced the expression of NF-κBp65, phosphorylated NF-κBp65, FoxO3a, and Bim. The observed antagonism to GU appeared to be associated with the NF-κB cell pathway. Additionally, qRT-PCR results indicate that DOP reduced the mRNA transcription levels of IL-6, and TNF-α, which shows that the healing of GU is related to the reduction in the inflammatory reaction by DOP. However, the expression of EGF and VEGF decreased, suggesting that the mechanism of DOP inhibiting GU may not be directly related to EGF and VEGF, or there is an uncertain competitive relationship between them, so further research is needed.

Dendrobium Nobile Alcohol Extract Extends the Lifespan of Caenorhabditis elegans via hsf-1 and daf-16.

Dendrobium nobile is a traditional Chinese herb with anti-inflammatory, antioxidant, and neuroprotective properties. However, its antiaging effects are unclear. Herein, we studied the aging-related functions and the mechanism of action of the alcohol extract of Dendrobium nobile (DnAE) in the model organism Caenorhabditis elegans. The results indicated that 1 mg/mL DnAE slowed lipofuscin accumulation, decreased the levels of reactive oxygen species, elevated superoxide dismutase activity, enhanced oxidative and heat stress resistance, extended the lifespan of nematodes, protected their dopamine neurons from 6-hydroxydopamine-induced neurodegeneration, and reduced Aß-induced neurotoxicity. DnAE upregulated the mRNA expression of the transcription factors DAF-16 and HSF-1, promoted the nuclear localization of DAF-16, and enhanced the fluorescence intensity of HSP-16.2. However, it had no effect on the lifespan of DAF-16 mutants. Thus, DnAE can significantly extend lifespan, enhance heat stress tolerance, and delay age-related diseases through a DAF-16-dependent pathway.

Residue analysis and dietary risk assessment of picoxystrobin in potato (Solanum tuberosum), citrus fruit (Citrus reticulata Blanco), and Dendrobium officinale Kimura et Migo.

Picoxystrobin is a systemic fungicide widely used on potato, citrus fruit, and Dendrobium officinale. To provide information for the risk assessment of potato, citrus, and Dendrobium officinale, field experiments combined with QuEChERS and HPLC-MS/MS were performed to detect picoxystrobin. Picoxystrobin had good linearity (R2 > 0.99), the average recovery rate was 75 - 102%, and the relative standard deviation was 1 - 11%. Picoxystrobin was utilized as the test agent in field experiments, and samples were evaluated and analyzed at various times after the final application utilizing random sampling. The results showed that picoxystrobin residuals in potato and citrus (orange meat) were ˂ 0.01 mg kg-1, whereas those in citrus whole fruit, D. officinale (fresh), and D. officinale (dried) were < 0.05 - 0.084, 0.16 - 3.82, and 0.34 - 9.05 mg kg-1, respectively. Based on these results, both the acute risk quotient (2.77%) and chronic risk quotient (8.7%) were ˂100%, and the dietary risk assessment indicated that the intake of picoxystrobin residues in potato, citrus fruit, and D. officinale did not pose a health risk. This study can guide the reasonable use of picoxystrobin in potato, citrus fruit, and D. officinale.

Bibenzyl and naphthalene derivatives from Dendrobium chrysanthum and their anti-hepatic-steatosis activities.

In this study, 16 new compounds, six bibenzyls (1-6) and 10 naphthalenes (7-13), including three pairs of naphthalene enantiomers and three known compounds (14-16), were isolated from Dendrobium chrysanthum. Structurally, compounds 1-5 are previously undescribed dimeric bibenzyls, uniquely linked by unusual carbon bonds. The structures of the compounds were determined using spectroscopy and X-ray crystallography. The screening results indicated that 1, 2, and 5 showed remarkable lipid-lowering activities in FFA-induced HepG2 cells, with EC50 values ranging from 3.13 to 6.57 µM. Moreover, 1, 2, and 5 significantly decreased both the mRNA and protein levels of the target SREBP-1c, and 5 also reduced PPARα mRNA and protein levels. Therefore, 1, 2, and 5 are potential drugs against hepatic steatosis by targeting PPARα or SREBP-1c.

Hypoglycemic Effects and Quality Marker Screening of Dendrobium nobile Lindl. at Different Growth Years.

(1) Background: The effect of Dendrobium nobile Lindl. (D. nobile) on hyperglycemic syndrome has only been recently known for several years. Materials of D. nobile were always collected from the plants cultivated in various growth ages. However, regarding the efficacy of D. nobile on hyperglycemic syndrome, it was still unknown as to which cultivation age would be selected. On the other hand, with the lack of quality markers, it is difficult to control the quality of D. nobile to treat hyperglycemic syndrome. (2) Methods: The effects of D. nobile cultivated at year 1 and year 3 were checked on alloxan-induced diabetic mice while their body weight, diet, water intake, and urinary output were monitored. Moreover, levels of glycosylated serum protein and insulin were measured using Elisa kits. The constituents of D. nobile were identified and analyzed by using UPLC-Q/trap. Quality markers were screened out by integrating the data from UPLC-Q/trap into a network pharmacology model. (3) Results: The D. nobile cultivated at both year 1 and year 3 showed a significant effect on hyperglycemic syndrome at the high dosage level; however, regarding the significant level, D. nobile from year 1 showed the better effect. In D. nobile, most of the metabolites were identified as alkaloids and sesquiterpene glycosides. Alkaloids, represented by dendrobine, were enriched in D. nobile from year 1, while sesquiterpene glycosides were enriched in D. nobile from year 3. Twenty one metabolites were differentially expressed between D. nobile from year 1 and year 3. The aforementioned 21 metabolites were enriched to 34 therapeutic targets directly related to diabetes. (4) Conclusions: Regarding the therapy for hyperglycemic syndrome, D. nobile cultivated at year 1 was more recommended than that at year 3. Alkaloids were recommended to be used as markers to control the quality of D. nobile for hyperglycemic syndrome treatment.

Dendrobium officinale flowers' topical extracts improve skin oxidative stress and aging.

BACKGROUND: Dendrobium officinale flowers (DOF) have the effects of antiaging and nourishing yin, but it lacks pharmacological research on skin aging. OBJECTIVE: Confirming the role of DOF in delaying skin aging based on the "in vitro animal-human" model. METHODS: In this experiment, three kinds of free radical scavenging experiments in vitro, D-galactose-induced aging mouse model, and human antiaging efficacy test were used to test whether DOF can improve skin aging through anti-oxidation. RESULTS: In vitro experiment shows that DOF has certain scavenging effect on 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical, hydroxyl free radical, and superoxide free radical, and its IC50 is 0.2090 µg/mL, 15.020, and 1.217 mg/mL respectively. DOF can enhance the activities of T-AOC, SOD, CAT, and GSH Px in the serum of aging mice, increase the content of GSH, and reduce the content of MDA when administered with DOF of 1.0, 2.0, and 4.0 g/kg for 6 weeks. In addition, it can enhance the activity of SOD in the skin of aging mice, increase the content of Hyp, and decrease the content of MDA, activated Keap1/Nrf2 pathway in the skin of aging mice. Applying DOF with a concentration of 0.2 g/mL on the face for 8 weeks can significantly improve the skin water score and elasticity value, reduce facial wrinkles, pores, acne, and UV spots, and improve the facial brown spots and roughness. CONCLUSION: DOF can significantly improve skin aging caused by oxidative stress, and its mechanism may be related to scavenging free radicals in the body and improving skin quality.