Traditional uses, chemical constituents, pharmacological activities, and toxicological effects of Dendrobium leaves: A review

Gigantol ameliorates DSS-induced colitis via suppressing β2 integrin mediated adhesion and chemotaxis of macrophage

ETHNOPHARMACOLOGICAL RELEVANCE

Dendrobium, recognized as "Shihu" in traditional Chinese medicine, holds a rich history of medicinal utilization documented in the Chinese Pharmacopoeia. Ancient texts like "Shen Nong Ben Cao Jing" extol Dendrobium's virtues as a superior herbal medicine fortifying "Yin" and invigorating the five viscera. Dendrobium is extensively employed for the treatment of gastrointestinal inflammatory disorders, showcasing significant therapeutic efficacy, particularly against ulcerative colitis (UC), within the realm of Chinese ethnopharmacology. Dendrobium plays crucial pharmacological roles due to its rich content of polysaccharides, alkaloids, phenanthrenes, and bibenzyls. Gigantol, a prominent bibenzyl compound, stands out as one of the most vital active constituents within Dendrobium, the gigantol content of Dendrobium leaves can reach approximately 4.79 μg/g. Its significance lies in being recognized as a noteworthy anti-inflammatory compound derived from Dendrobium.

AIM OF THE STUDY

Given the pivotal role of gigantol as a primary active substance in Dendrobium, the therapeutic potential of gigantol for gastrointestinal diseases remains enigmatic. Our present investigation aimed to evaluate the therapeutic effects of gigantol on dextran sulfate sodium (DSS)-induced colitis and reveal its potential mechanism in countering UC activity.

MATERIALS AND METHODS

The protective efficacy of gigantol against colitis was assessed by examining the histopathological changes and conducting biochemical analyses of colon from DSS-challenged mice. Assessments focused on gigantol's impact on improving the intestinal epithelial barrier and its anti-inflammatory effects in colonic tissues of colitis mice. Investigative techniques included the exploration of the macrophage inflammatory signaling pathway via qPCR and Western blot analyses. In vitro studies scrutinized macrophage adhesion, migration, and chemotaxis utilizing transwell and Zigmond chambers. Furthermore, F-actin and Rac1 activation assays detailed cellular cytoskeletal remodeling. The potential therapeutic target of gigantol was identified and validated through protein binding analysis, competitive enzyme-linked immunosorbent assay (ELISA), cellular thermal shift assay (CETSA), and drug affinity responsive target stability (DARTS) assay. The binding sites between gigantol and its target were predicted via molecular docking.

RESULTS

Gigantol ameliorated symptoms of DSS-induced colitis, rectified damage to the intestinal barrier, and suppressed the production of pro-inflammatory cytokines in colonic tissues. Intriguingly, gigantol significantly curtailed NF-κB signaling activation in the colons of DSS-induced colitis mice. Notably, gigantol impaired the β2 integrin-dependent adhesion and migratory capacity of RAW264.7 cells. Moreover, gigantol notably influenced the cytoskeleton remodeling of RAW264.7 cells by suppressing Vav1 phosphorylation and Rac1 activation. Mechanistically, gigantol interacted with β2 integrin, subsequently diminishing binding affinity with intercellular adhesion molecule-1 (ICAM-1).

CONCLUSIONS

In conclusion, these findings elucidate that gigantol ameliorates DSS-induced colitis by antagonizing β2 integrin-mediated macrophage adhesion, migration, and chemotaxis, thus it may impede macrophage recruitment and infiltration into colonic tissues. This study suggests that gigantol shows promise as a viable candidate for clinical colitis therapy.

Dendrobium officinale flos water extract ameliorates ethanol-induced acute gastric mucosal injury via inhibiting oxidative stress and inflammation

BACKGROUND

Dendrobium officinale flos (DOF), a novel food raw material, is used in Chinese folk medicine to nourish the stomach. However, there is still no available study to evaluate the effects of DOF on animal models of acute gastric injury and its mechanism by modern pharmacological research.

RESULTS

Herein, we characterized the major components of an aqueous extract of DOF and assessed its potential ameliorative effects in a rat model of acute gastric mucosal injury. The DOF water extract showed significant protective effects on the gastric mucosa and exhibited excellent antioxidant and anti-inflammatory activities. Acute gastric injury rat models induced by ethanol (6 mL kg-1) were pretreated with different doses of DOF water extract (50-100 mg kg-1 day-1), and the biological effects of DOF extract in gastric tissues were evaluated. DOF extract alleviated the symptoms of ethanol-stimulated acute gastric mucosal injury, as evidenced by a significant reduction in gastric injury index and the degree of gastric pathological changes. Additionally, treatment with DOF extract upregulated mucin expression in the gastric mucosa, attenuated oxidative stress, decreased the release of inflammatory mediators (TNF-α, IL-6), suppressed the expression of key proinflammatory enzymes (COX-2 and iNOS), reduced the phosphorylation of p38 MAPK and p65 NF-κB and increased the level of PGE2 in gastric tissues.

CONCLUSION

DOF exerts protective effects against ethanol-induced acute gastric mucosal injury, mainly by inhibiting inflammation and oxidative stress. © 2024 Society of Chemical Industry.

An improved deep learning network for image detection and its application in Dendrobii caulis decoction piece

In recent years, with the increasing demand for high-quality Dendrobii caulis decoction piece, the identification of D. caulis decoction piece species has become an urgent issue. However, the current methods are primarily designed for professional quality control and supervision. Therefore, ordinary consumers should not rely on these methods to assess the quality of products when making purchases. This research proposes a deep learning network called improved YOLOv5 for detecting different types of D. caulis decoction piece from images. In the main architecture of improved YOLOv5, we have designed the C2S module to replace the C3 module in YOLOv5, thereby enhancing the network's feature extraction capability for dense and small targets. Additionally, we have introduced the Reparameterized Generalized Feature Pyramid Network (RepGFPN) module and Optimal Transport Assignment (OTA) operator to more effectively integrate the high-dimensional and low-dimensional features of the network. Furthermore, a new large-scale dataset of Dendrobium images has been established. Compared to other models with similar computational complexity, improved YOLOv5 achieves the highest detection accuracy, with an average mAP@.05 of 96.5%. It is computationally equivalent to YOLOv5 but surpasses YOLOv5 by 2 percentage points in terms of accuracy.

Isolation and characterization of Paenibacillus peoriae JC-3jx from Dendrobium nobile

Dendrobium is a rich source of high-value natural components. Endophytic fungi are well studied, yet bacteria research is limited. In this study, endophytic bacteria from Dendrobium nobile were isolated using an improved method, showing inhibition of pathogens and growth promotion. JC-3jx, identified as Paenibacillus peoriae, exhibited significant inhibitory activity against tested fungi and bacteria, including Escherichia coli. JC-3jx also promoted corn seed rooting and Dendrobium growth, highlighting its excellent biocontrol and growth-promoting potential.

PPARα is one of the key targets for dendrobine to improve hepatic steatosis in NAFLD

ETHNOPHARMACOLOGICAL RELEVANCE

Dendrobium nobile Lindl. (DNL) is a traditional Chinese ethnobotanical herb. Dendrobine (DNE) has been designated as a quality indicator for DNL in the Chinese Pharmacopoeia. DNE exhibits various pharmacological activities, including the reduction of blood lipids, regulation of blood sugar levels, as well as anti-inflammatory and antioxidant properties.

AIM OF THE STUDY

The objective of this study is to explore the impact of DNE on lipid degeneration in nonalcoholic fatty liver disease (NAFLD) liver cells and elucidate its specific mechanism. The findings aim to offer theoretical support for the development of drugs related to DNL.

MATERIALS AND METHODS

We utilized male C57BL/6J mice, aged 6 weeks old, to establish a NAFLD model. This model allowed us to assess the impact of DNE on liver pathology and lipid levels in NAFLD mice. We investigated the mechanism of DNE's regulation of lipid metabolism through RNA-seq analysis. Furthermore, a NAFLD model was established using HepG2 cells to further evaluate the impact of DNE on the pathological changes of NAFLD liver cells. The potential mechanism of DNE's improvement was rapidly elucidated using HT-qPCR technology. These results were subsequently validated using mouse liver samples. Following the in vitro activation or inhibition of PPARα function, we observed changes in DNE's ability to ameliorate pathological changes in NAFLD hepatocytes. This mechanism was further verified through RT-qPCR and Western blot analysis.

RESULTS

DNE demonstrated a capacity to enhance serum TC, TG, and liver TG levels in mice, concurrently mitigating liver lipid degeneration. RNA-seq analysis unveiled that DNE primarily modulates the expression of genes related to metabolic pathways in mouse liver. Utilizing HT-qPCR technology, it was observed that DNE markedly regulates the expression of genes associated with the PPAR signaling pathway in liver cells. Consistency was observed in the in vivo data, where DNE significantly up-regulated the expression of PPARα mRNA and its protein level in mouse liver. Additionally, the expression of fatty acid metabolism-related genes (ACOX1, CPT2, HMGCS2, LPL), regulated by PPARα, was significantly elevated following DNE treatment. In vitro experiments further demonstrated that DNE notably ameliorated lipid deposition, peroxidation, and inflammation levels in NAFLD hepatocytes, particularly when administered in conjunction with fenofibrate. Notably, the PPARα inhibitor GW6471 attenuated these effects of DNE.

CONCLUSIONS

In summary, DNE exerts its influence on the expression of genes associated with downstream fat metabolism by regulating PPARα. This regulatory mechanism enhances liver lipid metabolism, mitigates lipid degeneration in hepatocytes, and ultimately ameliorates the pathological changes in NAFLD hepatocytes.

Optimization of the selection of suitable harvesting periods for medicinal plants: taking Dendrobium officinale as an example

BACKGROUND

Dendrobium officinale is a medicinal plant with high commercial value. The Dendrobium officinale market in Yunnan is affected by the standardization of medicinal material quality control and the increase in market demand, mainly due to the inappropriate harvest time, which puts it under increasing resource pressure. In this study, considering the high polysaccharide content of Dendrobium leaves and its contribution to today's medical industry, (Fourier Transform Infrared Spectrometer) FTIR combined with chemometrics was used to combine the yields of both stem and leaf parts of Dendrobium officinale to identify the different harvesting periods and to predict the dry matter content for the selection of the optimal harvesting period.

RESULTS

The Three-dimensional correlation spectroscopy (3DCOS) images of Dendrobium stems to build a (Split-Attention Networks) ResNet model can identify different harvesting periods 100%, which is 90% faster than (Support Vector Machine) SVM, and provides a scientific basis for modeling a large number of samples. The (Partial Least Squares Regression) PLSR model based on MSC preprocessing can predict the dry matter content of Dendrobium stems with Factor = 7, RMSE = 0.47, R2 = 0.99, RPD = 8.79; the PLSR model based on SG preprocessing can predict the dry matter content of Dendrobium leaves with Factor = 9, RMSE = 0.2, R2 = 0.99, RPD = 9.55.

CONCLUSIONS

These results show that the ResNet model possesses a fast and accurate recognition ability, and at the same time can provide a scientific basis for the processing of a large number of sample data; the PLSR model with MSC and SG preprocessing can predict the dry matter content of Dendrobium stems and leaves, respectively; The suitable harvesting period for D. officinale is from November to April of the following year, with the best harvesting period being December. During this period, it is necessary to ensure sufficient water supply between 7:00 and 10:00 every day and to provide a certain degree of light blocking between 14:00 and 17:00.

Two new sesquiterpene glycosides from Dendrobium findleyanum

One new ylangene-type sesquiterpene glycoside, findlayanoside C (1), and one new picrotoxane-type sesquiterpene glycoside, findlayanoside D (3), together with five known sesquiterpene glycosides, dendrofindlayanoside C (2), dendronobiloside B (4), dendronobiloside A (5), dendroside F (6) and dendromoniliside D (7), have been isolated from the stems of Dendrobium findleyanum. The structures of compounds 1 and 3 were elucidated by means of extensive spectroscopic analyses, and their absolute configuration were confirmed by electronic circular dichroism (ECD) calculations. Cytotoxic activity assays against SMMC-7721, A-549 and MCF-7 human cancer cell lines revealed IC50 values of 10.12, 12.32 and 14.13 μM for compound 1, and of 9.25, 13.16 and 16.26 μM for compound 2. This study enriches the anti-tumour sesquiterpenoids composition of D. findleyanum.

Diverse modulatory effects of bibenzyls from Dendrobium species on human immune cell responses under inflammatory conditions

Dendrobium plants are widely used in traditional Chinese medicine. Their secondary metabolites such as bibenzyls and phenanthrenes show various pharmacological benefits such as immunomodulation and inhibitory effects on cancer cell growth. However, our previous study also showed that some of these promising compounds (i.e., gigantol and cypripedin) also induced the expression of inflammatory cytokines including TNF in human monocytes, and thus raising concerns about the use of these compounds in clinical application. Furthermore, the effects of these compounds on other immune cell populations, apart from monocytes, remain to be investigated. In this study, we evaluated immunomodulatory effects of seven known bibenzyl compounds purified from Dendrobium species in human peripheral blood mononuclear cells (PBMCs) that were stimulated with lipopolysaccharide (LPS). Firstly, using flow cytometry, moscatilin (3) and crepidatin (4) showed the most promising dose-dependent immunomodulatory effects among all seven bibenzyls, determined by significant reduction of TNF expression in LPS-stimulated CD14+ monocytes. Only crepidatin at the concentration of 20 μM showed a significant cytotoxicity, i.e., an increased cell death in late apoptotic state. In addition, deep immune profiling using high-dimensional single-cell mass cytometry (CyTOF) revealed broad effects of Dendrobium compounds on diverse immune cell types. Our findings suggest that to precisely evaluate therapeutic as well as adverse effects of active natural compounds, a multi-parameter immune profiling targeting diverse immune cell population is required.

A case report of integrating Chinese and Western medicine: A new era in the treatment of stiff person syndrome

RATIONALE

At present, there are limitations to the treatment of stiff person syndrome (SPS). Current treatments are still ineffective or financially burdensome for some patients, so it is imperative to explore more appropriate treatments for patients. This is a case report of a SPS with a more significant effect of combined Chinese and Western medicine, which may provide new treatment ideas for other patients.

PATIENT CONCERNS

This patient presented with episodes of stiffness and pain in the lower back and lower extremities. His electromyography shows continued activation of normal motor units in the paraspinal and abdominal muscles. However, relevant laboratory tests including glutamic acid decarboxylase antibody and Amphiphysin antibody were negative. After a period of treatment including clonazepam, baclofen, prednisone and intravenous immunoglobulin, this patient experiences a shortened maintenance period of medication, accompanied by symptoms such as emotional anxiety and cognitive decline, which severely affects his life.

DIAGNOSES

This patient was diagnosed with SPS.

INTERVENTIONS

In May 2022 the patient decided to combine Chinese medicine for simultaneous treatment.

OUTCOMES

During the period of simultaneous treatment with Chinese and Western medicine, the patient experienced remission of clinical symptoms, reduction of concomitant symptoms and improved quality of life.

CONCLUSION

A combination of Western and Chinese medicine was effective in relieving this patient pain and stiffness and reducing the patient anxiety. Combined Chinese and Western medicine treatment may be able to bring better results to more patients with stiff person syndrome.

Sesquiterpenoids and bibenzyl derivative from Dendrobium hercoglossum

Three new sesquiterpenoids, dendrohercoglin A - C (1-3), and one new bibenzyl derivative, dendronbiline D (4), together with nine known sesquiterpenoids (5-13) were isolated from Dendrobium hercoglossum. The structures of the new compounds were elucidated by extensive spectroscopic analysis as well as NMR and ECD calculations. All the compounds were evaluated for their neuroprotective and anti-inflammatory activities. Compounds 2 and 3 increased the H2O2-damaged SH-SY5Y cell viabilities from 43.3% to 58.6% and 68.4%, respectively. Compound 4 exhibited pronounced anti-inflammatory activity with IC50 value of 9.5 ± 0.45 μM which was superior to the reference compound quercetin (IC50: 15.7 ± 0.89 μM).

A signal R3-type, CAPRICE-like MYB transcription factor from Dendrobium nobile controls trichome and root-hair development in Arabidopsis

The CAPRICE-like MYB transcription factors with R3 MYB motif play a central role in regulating trichome and root-hair development in plants. We identified the homologous gene of ENHANCER OF TRY AND CPC (ETC) in Arabidopsis from Dendrobium nobile Lindl with full cDNA sequence and genomic sequence (CAPRICE-LIKE MYB, DnCPL and DngCPL) respectively. Phylogenic analyses revealed a close relationship of CAPRICE-like MYB TFs between D. nobile and A. thaliana. Promoter analysis indicated that DnCPL is specifically expressed in trichome basal cells of leaf epidermis and root hairs. Overexpression of DnCPL results in the suppression of trichome formation and overproduction of root hairs. In transgenic plants overexpressing DnCPL and DngCPL, trichome formation was inhibited, moreover, no trichomes were observed in tissues of aerial parts, and root-hair differentiation was significantly enhanced by strongly repressing endogenous genes of AtCPC, AtTCL1, and AtTCL2 expression, thereby enhancing AtTRY expression. The DnCPL RNAi plants formed fewer lateral roots with a corresponding change in AtCPC, AtTCL1 and AtTCL2 expression. These results suggest that Dendrobium and Arabidopsis partially use similar transcription factors for epidermal cell differentiation and the CPC-like R3 MYB, DnCPL, may be a key common regulator of plant trichome and root-hair development. The results also provided genes and means of regulation to improve the survival ratio of artificially cultivated Dendrobium with more lateral roots.

Comparative Evaluation of the Physiochemical Properties, and Antioxidant and Hypoglycemic Activities of Dendrobium officinale Leaves Processed Using Different Drying Techniques

Dendrobium officinale leaves have the potential to be processed into natural antioxidants, functional foods, and food additives. To maximally maintain their quality, fresh D. officinale leaves were dehydrated using different drying methods, i.e., hot air drying (HD), microwave drying (MD), infrared drying (IRD), and freeze drying (FD), and then the physicochemical properties, microstructure, and biological activities of the dried samples were compared. The results showed that, with the FD method, the samples had a porous microstructure, maintained the highest phenolic content, and demonstrated the highest antioxidant and hypoglycemic activities. Among the three thermal drying methods, with the IRD method, the samples retained higher phenolic contents, showed stronger DPPH free-radical scavenging, ferric ion reducing, ferrous ion chelating, and α-glucosidase inhibitory abilities, and more strongly promoted glucose metabolism in insulin-resistant HL-7702 cells than the samples with the MD and HD methods. These results suggested that FD was the most suitable method. However, IRD might be a promising alternative, owing to the high cost and long time needed for FD for the large-scale drying of D. officinale leaves.

Genome-Wide Identification and Characterization of the NAC Gene Family and Its Involvement in Cold Response in Dendrobium officinale

The NAC (NAM, ATAF1/2 and CUC2) gene family is one of the largest plant-specific transcription factor families, functioning as crucial regulators in diverse biological processes such as plant growth and development as well as biotic and abiotic stress responses. Although it has been widely characterized in many plants, the significance of the NAC family in Dendrobium officinale remained elusive up to now. In this study, a genome-wide search method was conducted to identify NAC genes in Dendrobium officinale (DoNACs) and a total of 110 putative DoNACs were obtained. Phylogenetic analysis classified them into 15 subfamilies according to the nomenclature in Arabidopsis and rice. The members in the subfamilies shared more similar gene structures and conversed protein domain compositions. Furthermore, the expression profiles of these DoNACs were investigated in diverse tissues and under cold stress by RNA-seq data. Then, a total of five up-regulated and five down-regulated, cold-responsive DoNACs were validated through QRT-PCR analysis, demonstrating they were involved in regulating cold stress response. Additionally, the subcellular localization of two down-regulated candidates (DoNAC39 and DoNAC58) was demonstrated to be localized in the nuclei. This study reported the genomic organization, protein domain compositions and expression patterns of the NAC family in Dendrobium officinale, which provided targets for further functional studies of DoNACs and also contributed to the dissection of the role of NAC in regulating cold tolerance in Dendrobium officinale.

1,5,6-Trimethoxy-2,7-dihydroxyphenanthrene from Dendrobium officinale Exhibited Antitumor Activities for HeLa Cells

Natural products are irreplaceable reservoirs for cancer treatments. In this study, 12 phenanthrene compounds were extracted and isolated from Dendrobium officinale. Each chemical structure was identified using comprehensive NMR analysis. All compounds were evaluated for their cytotoxic activities against five tumor cell lines, i.e., HeLa, MCF-7, SK-N-AS, Capan-2 and Hep G2. Compound 5, 1,5,6-trimethoxy-2,7-dihydroxyphenanthrene, displayed the most significant cytotoxic effect against HeLa and Hep G2 cells, with an IC50 of 0.42 and 0.20 μM. For Hela cells, further experiments demonstrated that compound 5 could obviously inhibit cell migration, block cell cycle in the G0/G1 phase and induce apoptosis. Expression measurements for p53 indicated that knock down of p53 by siRNA could mitigate the apoptosis induced by compound 5. Therefore, the compound 5 is a potential candidate drug for HeLa cells in cervical cancer.

Multiple pesticide residues and risk assessment of Dendrobium officinale Kimura et Migo: a three-year investigation

Dendrobium officinale Kimura et Migo (D. officinale) is a traditional Chinese medicine homologous to food, and its safety has attracted considerable attention. Pesticide residues are critical indicators for evaluating the safety of D. officinale. This study investigated the levels of 130 pesticides in 137 stem samples and 82 leaf samples from five main production areas of D. officinale in Zhejiang Province, along with the associated risk of dietary exposure for the population between 2019 and 2021. Forty-five pesticides were detected in 171 samples, of which pyraclostrobin had the highest detection frequency. Multiple residues were detected in 52.56% of the stem samples and 54.88% of the leaf samples, and one stem sample contained up to 18 pesticides. Here, the level of difenoconazole in three samples (two stem samples and one leaf sample) was higher than the maximum residue limit (MRL) in China. Considering the possible health risks related to pesticide residues, a risk assessment of human exposure to pesticides via the intake of D. officinale stems and leaves was evaluated, indicating negligible short-term, long-term, and cumulative risks to human health. However, considering the high detection rate of unregistered pesticides, the supplementation of pesticide registration information on D. officinale should be expedited, and MRLs should be established to ensure food and drug safety.

Anti-inflammatory and α-glucosidase inhibitory constituents from Dendrobium nobile Lindl

Four new compounds ((±)-1-3), including one pair of enantiomers ((±)-1), along with 11 known bibenzyls (4-14) were isolated from Dendrobium nobile. The structures of the new compounds were elucidated by spectroscopic methods including 1D and 2D NMR as well as HRESIMS. The configurations of (±)-1 were established via the electronic circular dichroism (ECD) calculations. Compounds (+)-1 and 13 displayed pronounced α-glucosidase inhibitory activities with IC50 values of 16.7 ± 2.3 and 13.4 ± 0.2 μM, respectively, which were comparable to that of genistein (IC50, 8.54 ± 0.69 μM). Kinetic studies revealed that (+)-1 and 13 were non-competitive inhibitors against α-glucosidase and molecular docking simulations illuminated their interactions with α-glucosidase. All the isolates were also evaluated for their anti-inflammatory activities. Compounds 4, 5, and 11 exhibited superior inhibition activity with IC50 values ranging from 9.2 to 13.8 μM to that of quercetin (IC50, 16.3 ± 1.1 μM).

Antimicrobial peptides in Dendrobium officinale: Genomic parameters, peptide structures, and gene expression patterns

A weak codon usage bias was found in Dendrobium catenatum (D. officiale) antimicrobial peptides (AMPs), after the analysis of relative synonymous codon usage, GC contents, and the effective number of codons. The codon usage preference was mainly influenced by natural selection pressure. The self-optimized prediction method and SWISS-MODEL were applied for peptide structural and domain analyses, and some typical antimicrobial domains were found in D. officinale AMP amino sequences, such as knot1 domain, gibberellins-stimulated domain, cupin_1 domain, defensin_like domain, and SLR1-BP (S locus-related glycoprotein 1 binding pollen coat protein) domain. To investigate the AMPs gene expression pattern, abiotic stresses, such as salt stress, drought stress, salicylic acid (SA), and methyl jasmonate (JA), were applied and the gene expression levels were detected by the real-time fluorescent quantitative polymerase chain reaction. Results showed that, even though the basic AMPs gene expressions were low, some AMPs can still be induced by salt dress, while the drought dress did not show the same impact. The SA and JA signaling pathways might be involved in most of the AMPs expressions. The natural selection of the D. officinale AMPs and thus forming diverse types of AMPs enhanced the plant's innate immunity and disease resistance capability, which would lead to a better understanding of the molecular mechanism for D. officinale adapting to the environment. The finding that salt stress, SA, and JA signaling pathways can induce AMP expression lays a foundation for the further development and functional verification of D. officinale AMPs.

Inhibitory effect of Dendrobium officinale polysaccharide on oxidative damage of glial cells in aging mice by regulating gut microbiota

Polysaccharides extracted from Dendrobium officinale have various physiological effects. In this study, we used D-galactose-induced senescent mice as an animal model to investigate the inhibitory effects of Dendrobium officinale polysaccharide (DOP) on oxidative damage in glial cells by attenuating oxidative stress and modulating the gut microbiota. The results showed that DOP significantly alleviated the activation of glial cells, increased the activity of antioxidant enzymes and reduced the MDA content in senescent mice. In addition, DOP reshaped the disordered gut microbiota, decreased the abundance ratio of Firmicutes to Bacteroidetes and increased the abundance of beneficial bacteria Lactobacillus. DOP may reverse the gut microbiota disturbance and alleviate the oxidative damage of glial cells, therefore exert potential neuroprotective effects by modulating gut microbiota.

Comprehensive chemical profiling of two Dendrobium species and identification of anti-hepatoma active constituents from Dendrobium chrysotoxum by network pharmacology

BACKGROUND

Dendrobium nobile and Dendrobium chrysotoxum are important species of the genus Dendrobium and have great economic and medicinal value. However, the medicinal properties of these two plants remain poorly understood. This study aimed to investigate the medical properties of D. nobile and D. chrysotoxum by conducting a comprehensive chemical profiling of the two plants. Additionally, active compounds and predictive targets for anti-hepatoma activity in D. chrysotoxum extracts were identified using Network Pharmacology.

RESULTS

Chemical profiling showed that altogether 65 phytochemicals were identified from D. nobile and D. chrysotoxum, with major classes as alkaloids, terpenoids, flavonoids, bibenzyls and phenanthrenes. About 18 compounds were identified as the important differential metabolites in D. nobile and D. chrysotoxum. Furtherly, CCK-8 results showed that the extracts of stems and leaves of D. nobile and D. chrysotoxum could inhibit the growth of Huh-7 cells, and the anti-hepatoma activity of extracts were dose-dependent. Among the extracts, the extract of D. chrysotoxum showed significant anti-hepatoma activity. In order to find the potential mechanism of anti-hepatoma activity of D. chrysotoxum, five key compounds and nine key targets were obtained through constructing and analyzing the compound-target-pathway network. The five key compounds were chrysotobibenzyl, chrysotoxin, moscatilin, gigantol and chrysotoxene. Nine key targets, including GAPDH, EGFR, ESR1, HRAS, SRC, CCND1, HIF1A, ERBB2 and MTOR, could be considered as the core targets of the anti-hepatoma activity of D. chrysotoxum.

CONCLUSIONS

In this study, the chemical composition difference and anti-hepatoma activity of stems and leaves of D. nobile and D. chrysotoxum were compared, and the potential anti-hepatoma mechanism of D. chrysotoxum was revealed in a multi-target and multi-pathway manner.

Dendrobium as a new natural source of bioactive for the prevention and treatment of digestive tract diseases: A comprehensive review with future perspectives

BACKGROUND

The incidence of diseases related to the digestive tract is on the rise, with many types of complex etiologies. Dendrobium nobile Lindl. is a famous Traditional Chinese Medicine (TCM) rich in many bioactives proven to be beneficial in several health diseases related to inflammation and oxidative stress.

PURPOSE

At present, despite the availability of various therapeutic clinical drugs used for the treatment of digestive tract diseases, resistance emergence and existence of several side effects warrant for the developing of novel drugs for improved effects on digestive tract diseases.

METHODS

"Orchidaceae", "Dendrobium", "inflammation", "digestive tract", and "polysaccharide" were used as search terms to screen the literature. The therapeutic use of Dendrobium related to digestive tract diseases relative to known polysaccharides and other bioactive compounds were derived from online databases, including Web of Science, PubMed, Elsevier, Science Direct, and China National Knowledge Infrastructure, as well as relevant information on the known pharmacological actions of the listed phytochemicals.

RESULTS

To better capitalize upon Dendrobium for preventing and treating diseases related to digestive tract, this review summarizes bioactives in Dendrobium reported of potential in digestive tract diseases management and their underlying action mechanisms. Studies revealed that Dendrobium encompasses diverse classes including polysaccharides, phenolics, alkaloids, bibenzyls, coumarins, phenanthrene and steroids, with polysaccharide as the major class. Dendrobium exerts various health effects on a variety of disease related to the digestive tract. Action mechanisms involve antioxidant, anti-inflammatory, anti-apoptotic, antioxidant, anticancer, alongside the regulation of some key signaling pathways.

CONCLUSION

Overall, Dendrobium appears as a promising TCM source of bioactives that has the potential to be further developed into nutraceuticals for digestive tract diseases compared to current drug treatments. This review highlights for Dendrobium potential effects with future perspectives for needed future research to maximize the use of bioactive compounds from Dendrobium for digestive tract disease treatment. A compile of Dendrobium bioactives is also presented alongside methods for their extraction and enrichment for potential incorporation in nutraceuticals.

Immunomodulatory Effects of New Phenanthrene Derivatives from Dendrobium crumenatum

Three new phenanthrene derivatives (1, 2, 4), one new fluorenone (3), and four known compounds (5-8) were isolated from the ethyl acetate extract of Dendrobium crumenatum Sw. stems using column chromatography. The chemical structures were elucidated by analysis of spectroscopic data. The absolute configuration of 4 was determined by electronic circular dichroism calculation. We also evaluated the immunomodulatory effects of compounds isolated from D. crumenatum in human peripheral blood mononuclear cells from healthy individuals and those from patients with multiple sclerosis in vitro. Dendrocrumenol B (2) and dendrocrumenol D (4) showed strong immunomodulatory effects on both CD3⁺ T cells and CD14⁺ monocytes. Compounds 2 and 4 could reduce IL-2 and TNF production in T cells and monocytes that were treated with phorbol-12-myristate-13-acetate and ionomycin (PMA/Iono). Deep immune profiling using high-dimensional single-cell mass cytometry could confirm immunomodulatory effects of 4, quantified by the reduction of activated T cell population under PMA/Iono stimulation, in comparison to the stimulated T cells without treatment.

Assessment of Antioxidant, Anti-Lipid Peroxidation, Antiglycation, Anti-Inflammatory and Anti-Tyrosinase Properties of Dendrobium sulcatum Lindl

Dendrobium sulcatum Lindl or “Ueang Jampa-Nan” (Orchidaceae family) is widely dis-tributed in Thailand and Laos. It is classified in the genus Dendrobium, which is used in both traditional Chinese medicine and Ayurvedic medicine for health enhancement and anti-aging. The purpose of this study was to investigate the phytochemical constituents and bioefficacy of stems, leaves and flowers from D. sulcatum for cosmetic and cosmeceutical applications. Phenolic and flavonoid contents were tested for the phytochemical evaluation. The antioxidant (DPPH, FRAP and ABTS assays), anti-lipid peroxidation, antiglycation, anti-inflammatory and anti-tyrosinase properties were assessed for their bioefficacy. The results showed that the extracts of stem and leaf had higher total phenolic content than that of the flower, and the leaf extract had the highest flavonoid content. The antioxidant, anti-lipid peroxidation and anti-inflammatory activities of the extracts were greater in those from the stem and leaf compared with that of the flower. The leaf extract exhibited the greatest antiglycation property. The results of anti-tyrosinase analysis of the extracts showed that the leaf and flower exhibited potent activities with a percentage inhibition greater than 70% (at a concentration of 50 µg/mL). In conclusion, these findings suggest that the ethanolic extracts from different parts of D. sulcatum are promising sources of natural active ingredients for further cosmetic and cosmeceutical products.

Two new alkaloids from Dendrobium nobile Lindl. exhibited neuroprotective activity, and dendrobine alleviated Aβ1-42 -induced apoptosis by inhibiting CDK5 activation in PC12 cells

Dendrobium nobile Lindl. is registered in the Chinese Pharmacopoeia as a traditional medicine. Phytochemical investigation of the ethanol extract of D. nobile Lindl. stems yielded three alkaloid compounds, including two new compounds dendroxine B (2) and denrine B (3) as well as one known compound dendrobine (1). Here, we identified the structure of these compounds using spectroscopic analyses and compared them with those described in previous studies. Compounds 1-3 were found to show protective effect against amyloid-β 1-42 (Aβ_1-42 )-induced neurotoxicity in rat pheochromocytoma (PC12) cells, among which dendrobine exhibited the most significant neuroprotective effect. Hoechst 33342/propidium iodide staining indicated that dendrobine ameliorated Aβ_1-42 -induced apoptosis. Moreover, quantitative real-time polymerase chain reaction and western blot analysis analysis demonstrated that dendrobine suppressed the activation of cyclin-dependent kinase 5 (CDK5), upregulated Bcl-2 expression, and downregulated Bax, cyto-c, and caspase-3 expression. Molecular docking analysis and surface plasmon resonance assay suggested that dendrobine directly bound to CDK5 protein with a KD value of 2.05 × 10^-4  M. In summary, alkaloids are the neuroprotective constituents of D. nobile Lindl., and dendrobine protected PC12 cells against Aβ_1-42 -induced apoptosis by inhibiting CDK5 activation.

Targeting the Interplay of Autophagy and ROS for Cancer Therapy: An Updated Overview on Phytochemicals

Autophagy is an evolutionarily conserved self-degradation system that recycles cellular components and damaged organelles, which is critical for the maintenance of cellular homeostasis. Intracellular reactive oxygen species (ROS) are short-lived molecules containing unpaired electrons that are formed by the partial reduction of molecular oxygen. It is widely known that autophagy and ROS can regulate each other to influence the progression of cancer. Recently, due to the wide potent anti-cancer effects with minimal side effects, phytochemicals, especially those that can modulate ROS and autophagy, have attracted great interest of researchers. In this review, we afford an overview of the complex regulatory relationship between autophagy and ROS in cancer, with an emphasis on phytochemicals that regulate ROS and autophagy for cancer therapy. We also discuss the effects of ROS/autophagy inhibitors on the anti-cancer effects of phytochemicals, and the challenges associated with harnessing the regulation potential on ROS and autophagy of phytochemicals for cancer therapy.

Effects of a Macroporous Resin Extract of Dendrobium officinale Leaves in Rats with Hyperuricemia Induced by Anthropomorphic Unhealthy Lifestyle

Aim

Hyperuricemia (HUA) has received increased attention in the last few decades due to its global prevalence. Our previous study found that administration of a macroporous resin extract of Dendrobium officinale leaves (DoMRE) to rats with HUA that was induced by exposure to potassium oxazine combined with fructose and a high-purine diet led to a significant reduction in serum uric acid (SUA) levels. The aim of this study was to explore the effects of DoMRE on hyperuricemia induced by anthropomorphic unhealthy lifestyle and to elucidate its possible mechanisms of action.

Methods

Dosages (5.0 and 10.0 g/kg/day) of DoMRE were administered to rats daily after induction of HUA by anthropomorphic unhealthy lifestyle for 12 weeks. The levels of UA in the serum, urine, and feces; the levels of creatinine (Cr) in the serum and urine; and the levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum were all measured using an automatic biochemical analyzer. The activities of xanthine oxidase (XOD) and adenosine deaminase (ADA) in the serum, liver, and intestine tissue supernatant were measured using appropriate kits for each biological target. The expressions levels of UA transporters (ABCG2 and GLUT9), tight junction (TJ) proteins (ZO-1 and occludin), and inflammatory factors (IL-6, IL-8, and TNF-α) in the intestine were assayed by immunohistochemical (IHC) staining. Hematoxylin and eosin (H&E) staining was used to assess histological changes in the renal and intestinal tissues.

Results

DoMRE treatment significantly reduced SUA levels and concomitantly increased fecal UA (FUA) levels and the fractional excretion of UA (FEUA) in HUA rats. Furthermore, DoMRE significantly reduced both the XOD activity in the serum, liver, and intestine and the ADA activity in the liver and intestine. DoMRE also effectively regulated the expression of GLUT9 and ABCG2 in the intestine, and it significantly upregulated the expression of the intestinal TJ proteins ZO-1 and occludin. Therefore, DoMRE reduced the damage to the intestinal barrier function caused by the increased production of inflammatory factors due to HUA to ensure normal intestinal UA excretion.

Conclusion

DoMRE demonstrated anti-HUA effects in the HUA rat model induced by an anthropomorphic unhealthy lifestyle, and the molecular mechanism appeared to involve the regulation of urate transport-related transporters (ABCG2 and GLUT9) in the intestine, protection of the intestinal barrier function to promote UA excretion, and inhibition of XOD and ADA activity in the liver and intestine to inhibit UA production in the HUA-induced rats.

Dendrobium Nobile Polysaccharides Attenuates Ferroptosis and Improves Cognitive Function in Vascular Dementia Rats

INTRODUCTION

To investigate the neuroprotective effect and mechanism of Dendrobium nobile polysaccharide (DNP) on vascular dementia (VD) rats.

METHODS

VD model rats were prepared by permanent ligation of bilateral common carotid arteries. Cognitive function was tested by morris water maze test, mitochondrial morphology and ultrastructure of hippocampal synapses were tested by transmission electron microscopy, GSH, xCT, GPx4, and PSD-95 expressions were tested by western blot and PCR.

RESULTS

The number of platform crossing was significantly increased, and the escape latency was significantly shorter in DNP group. The expressions of GSH, xCT and GPx4 in the hippocampus were up-regulated in DNP group. Moreover, the synapses of DNP group were relatively intact and synaptic vesicles increased, the length of synaptic active zone and PSD thickness were significantly increased, and PSD-95 protein expression was significantly up-regulated compared VD group.

CONCLUSION

DNP may take a neuroprotective effect by inhibiting ferroptosis in VD.

Dendrobium and its active ingredients: Emerging role in liver protection

Dendrobium is a traditional medicinal plant, which has a variety of clinical applications in China. It has been reported that Dendrobium contains various bioactive components, mainly including polysaccharides and alkaloids. Previous studies have shown that Dendrobium has pharmacological activities including antiviral, anti-inflammatory, and antioxidant effects, as well as immune regulation. Particularly, the anti-aging functions and neuroprotective effects of Dendrobium have been well characterized in a wide array of cell and animal models. In recent years, the effect of Dendrobium on the liver has emerged as a new direction to explore its therapeutic benefits and has received more and more attention. This review is focused on the beneficial effects of Dendrobium on liver toxicity and various liver disorders, which presumably are attributed to a consequence of an array of modes of action due to its multiple bioactive components, and largely lack mechanistic and pharmacokinetic characterization. A particular emphasis is placed on the potential action mechanisms related to Dendrobium's liver protection. Research perspectives in regard to the potential therapeutic application for Dendrobium are also discussed in this review.

A review of plant antipathogenic constituents: Source, activity and mechanism

Green prevention and control of plant pathogens is a development direction of sustainable and low-carbon agriculture given the limitation of traditional chemicals. Plant-derived antipathogenic constituents (PAPCs) exhibit the advantages of being environmental benign and a broad spectrum of target pathogens over traditional chemicals. Here, we review the research advances on plant sources, chemical compositions, activities of antipathogenic constituents in the past 20 years. Reported PAPCs are classified into categories of phenols, flavonoids, terpenoids, alkaloids and antimicrobial peptides. Angiosperms, gymnosperms and some lower plants are the main plant source of detected PAPCs. The PAPCs act on pathogens through multiple pathways including destroying cell structures, blocking key composition synthesis and inhibiting cell metabolism. The development trends of PAPCs are finally prospected. This review serves as a comprehensive review on the study of plant antipathogenic constituents and a key reference for forecasting the source, characteristic and activity of PAPC.

Antioxidant and anti-inflammatory activity of constituents isolated from Dendrobium nobile (Lindl.)

Dendrobium nobile (Lindl.) have long been used as herbal tea and a traditional herbal medicine to treat Alzheimer’s disease (AD). In the current study, nineteen compounds (1–19), including two new vitamin E homologues (1–2), one new sesquiterpene (6), and two new dendrobines (7, 8), were isolated and identified from stems of Dendrobium nobile. Their structures were elucidated on the basis of NMR, ¹³C NMR calculation, and DP4⁺ probability analyses. The absolute configurations of new compounds were determined by electronic circular dichroism (ECD) data analysis. Antioxidant, anti-inflammatory, and cytotoxic activities of isolated compounds were evaluated. Among them, compound 2 demonstrated significant antioxidant activity compared with ascorbic acid (VC), while compounds 2 and 4 also exhibited an equal effect to positive control cisplatin. This study on the biological activity of the new vitamin E homologues from Dendrobium nobile may indicate its potential application in the pharmaceutical and food industries.

The Extracts of Dendrobium Alleviate Dry Eye Disease in Rat Model by Regulating Aquaporin Expression and MAPKs/NF-κB Signalling

Dry eye is one of the most common ocular surface diseases caused by tear film instability and ocular surface damage due to an abnormal quality or quantity of tears. Inflammatory factors can initiate relevant transduction signalling pathways and trigger the inflammatory cascade response, resulting in ocular surface inflammation. It has been shown that the active ingredients in Dendrobium, such as polysaccharides, alkaloids and phenols, have anti-inflammatory, anti-tumour and immunity-boosting effects, and Dendrobium officinale extract can improve glandular secretion function, increase salivary secretion and increase the expression level of water channel protein in salivary glands in patients with dry eye syndromes. We investigated the in vitro cytoprotective effect of Dendrobium extracts in sodium chloride induced hyperosmotic conditions in human cornea keratocytes (HKs). Results showed that Dendrobium officinale Kimura et Migo water extract (DOW) and Dendrobium loddigesii Rolfe water extract (DLW) could upregulate the expression of aquaporins (AQP)5 protein, thus exerting a repairing effect by promoting cell migration. Furthermore, oral administration of DOW and DLW enhanced tear production in rats and exerted a protective effect on ocular surface damage. DOW and DLW could upregulate the expression of AQP5 and mucin (muc)5ac proteins in the lacrimal gland and reduce the inflammatory response. DOW and DLW inhibited the activation of the corresponding mitogen-activated protein kinases (MAPK) and NF-KB pathway, thereby playing a role in improving dry eye symptoms. This study provides a new perspective on dry eye treatment, and DOW and DLW may be potential therapeutic agents for dry eye.

Effect of cultivation mode on bacterial and fungal communities of Dendrobium catenatum

Background

The orchid growth and development often associate with microbes. However, the interaction between plant performance and microbial communities within and surrounding plants is less understood. Dendrobium catenatum, which used to be an endangered orchid species, has become a billion dollar industry in China. Simulated natural cultivation modes, such as living tree epiphytic (LT) and cliff epiphytic (CE) cultivations, improve the production or quality of D. catenatum and contribute to the development of D. catenatum industry. In a previous study, morphological characteristics, anatomical structure, and main bioactive components (polysaccharides and ethanol-soluble extractives) of D. catenatum grown under LT and CE significantly differed from a facility cultivation mode, pot (PO) cultivation, were observed. Whether cultivation mode affects bacterial and fungal communities of D. catenatum, thereby affecting the chemical quality of this plant, need to be explored.

Results

Both three plant organs (leaf, stem, and root) and cultivating substrates obtained under three cultivation modes: living tree epiphytic (LT), cliff epiphytic (CE), and pot (PO) cultivation were examined by adopting high-throughput sequencing methods. Subsequently, bacterial and fungal correlations with D. catenatum main chemical components, stem polysaccharides and ethanol-soluble extractives and leaf phenols and flavonoids, were elucidated. The results showed that microbial communities of the plants and substrates are both influenced by the cultivation mode. However, the plants and their cultivating substrates exhibited different patterns of bacterial and fungal composition, with clearly distinguished dominant bacterial groups, but shared dominance among fungal groups. Bacteria and fungi differed in abundance, diversity, and community structure, depending on the cultivation environment and plant organ. Both bacterial and fungal communities were affected by cultivation mode and plant organ. In both plants and substrates, PO bacterial and fungal community structure differed significantly from those of LT and CE modes. Bacterial and fungal community structure differed significantly between roots and the other two plant organs examined (stems and leaves). Several bacteria and fungi were positively correlated with main chemical components in D. catenatum.

Conclusions

The findings indicate that microbial communities of the plants and substrates were both influenced by the cultivation mode and plant organ, and some of them were positively correlated with main chemical components in D. catenatum. The research would enhance our understanding of interactions between Dendrobium and the microbial environment, and to provide a theoretical basis for the development of improved D. catenatum cultivation methods.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12866-022-02635-6.

Picrotoxane sesquiterpenoids: chemistry, chemo- and bio-syntheses and biological activities

Covering: up to December 2021Picrotoxane sesquiterpenoids are a special category of natural products known to have a picrotoxane skeleton and are characterised by a highly oxidised cis-hydrindene core, lactone rings, and epoxide functionalities. Ever since the first picrotoxane was isolated from Menispermum cocculus in the early 19^th century, these compounds have long attracted the attention of natural product chemists, synthetic chemists, and pharmacologists for their particular structures and powerful biological activities. This review extensively summarizes a total of 132 naturally occurring picrotoxane sesquiterpenoids, taking into account their distributions, structural classifications, chemical and bio-synthetic researches, and bioactivities. It provides a comprehensive and in-depth perspective for further investigation on picrotoxane sesquiterpenoids.

Selection of Suitable Reference Genes for Gene Expression Normalization Studies in Dendrobium huoshanense

Dendrobium huoshanense is a kind of precious herb with important medicinal and edible value in China, which is widely used in traditional Chinese medicine for various diseases. Recent studies have paid close attention to the genetic expression of the biosynthetic pathway of the main active components (polysaccharides, alkaloids, and flavonoids), and real-time polymerase chain reaction (qPCR) is one of the most widely used methods for doing so. However, so far, no reference gene selections have been reported in D. huoshanense. In this study, 15 reference gene candidates (GAPDH, eIF, EF-1α, PP2A, UBCE, RPL5, TBP, APT1, MDH, PTBP3, PEPC, CYP71, NCBP2, TIP41, and F-box) were selected and evaluated for their expression stability in D. huoshanense under various experimental conditions, including in different tissues (root, stem, and leaf), abiotic stresses (oxidative, drought, cold, and UV), and hormone treatment (methyl jasmonate) using three statistical programs (geNorm, NormFinder, and BestKeeper). Then, the RefFinder program was employed to comprehensively validate the stability of the selected reference genes. Finally, the expression profiles of the CESA and GMPP genes were further analyzed, and these results indicated that TBP, NCBP2, and CYP71 were the top three most stable reference genes after comprehensive comparison, which could be used as stable reference genes for normalizing the genes expression in D. huoshanense. This study described here provides the first data regarding on reference gene selection in D. huoshanense, which will be extremely beneficial for future research on the gene expression normalization in D. huoshanense.

Unravelling the key aroma compounds in the characteristic fragrance of Dendrobium officinale flowers for potential industrial application

Dendrobium officinale Kimura et Migo, one of the most important orchids because of its medicinal and edible value, has a typical Dendrobium Sw. flora scent, which has great application potential and commercial value to be characterized. The aroma-active compounds originating from D. officinale fresh flowers (DFF) were investigated using a sensomics approach. A combined solid phase microextraction and solvent-assisted flavor evaporation method were used to accurately capture the overall aromatic profile. Exactly 34 odorants were detected and identified by aroma extract dilution analysis (AEDA) coupled with gas chromatography/olfactometry-mass spectrometry (GC/O-MS) in DFF, of which nine odorants had a flavor dilution (FD) factor ≥27. All 34 odorants were further quantified. The odor activity values (OAVs) were calculated with the highest value of 7444, in which 18 compounds were confirmed to be key odorants, including 1-octen-3-ol, hexanal, nonanal, phenylacetaldehyde, linalool, 4-oxoisophorone, theaspirane, methyl salicylate, etc. Among the studies above, 42 out of 78 volatiles and 14 out of 34 odorants were identified in DFF for the first time. Then, the aroma profile of the DFF was simulated successfully by aroma recombination experiments based on the quantitation results, and the omission test suggested that alcohols are the decisive type of compounds in the DFF key odorants. In addition, a progressive addition test showed that the aroma recombinate prepared with 18 reference key odorants was able to reconstruct the characteristic aroma of DFF. In comparison, the recombinate constituted by mixing all 34 reference odorants in the same concentrations as determined in the DDF sample could mimic the flower scent and closely match the sensory attributes of the original D. officinale fresh flower.

Batatasin III, a Constituent of Dendrobium scabrilingue, Improves Murine Pain-like Behaviors with a Favorable CNS Safety Profile

Batatasin III is a stilbenoid compound present in a wide variety of Dendrobium species. Although the pharmacological efficacy of batatasin III has been reported in several disease models, its antinociceptive efficacy and central nervous system (CNS) side effects remain unknown. Thus, this study examined the effects of batatasin III on pain-like behaviors in mouse models of formalin- and lipopolysaccharide (LPS)-induced inflammatory pain. The results revealed a significant antinociceptive effect of batatasin III in both models, as 50 mg/kg batatasin III elicited comparable antinociception as 10 mg/kg indomethacin. Further, the anti-inflammatory effect of batatasin III was assessed in LPS-induced RAW 264.7 macrophages and BV-2 microglial cells. The compound significantly reduced the levels of inflammatory mediators (nitric oxide, TNF-α, and IL-6) in LPS-stimulated cells in a concentration-dependent manner. Following efficacy evaluations, the potential CNS side effects of batatasin III were evaluated using the rotarod test and the Laboratory Animal Behavior Observation, Registration, and Analysis System. Batatasin III-treated mice exhibited comparable forced, spontaneous, and general locomotive behaviors to vehicle-treated mice, indicating no potential CNS side effects. Overall, this study demonstrated the preclinical antinociceptive efficacy and CNS safety of batatasin III, suggesting its potential role in the development of new analgesics.

Research progress on extraction, purification, structure and biological activity of Dendrobium officinale polysaccharides

Dendrobium officinale Kimura et Migo (D. officinale) is a traditional medicinal and food homologous plant that has been used for thousands of years in folk medicine and nutritious food. Recent studies have shown that polysaccharide is one of the main biologically active components in D. officinale. D. officinale polysaccharides possess several biological activities, such as anti-oxidant, heptatoprotective, immunomodulatory, gastrointestinal protection, hypoglycemic, and anti-tumor activities. In the past decade, polysaccharides have been isolated from D. officinale by physical and enzymatic methods and have been subjected to structural characterization and activity studies. Progress in extraction, purification, structural characterization, bioactivity, structure-activity relationship, and possible bioactivity mechanism of polysaccharides D. officinale were reviewed. In order to provide reference for the in-depth study of D. officinale polysaccharides and the application in functional food and biomedical research.

Transcriptome and Metabonomics Analysis Revealed the Molecular Mechanism of Differential Metabolite Production of Dendrobium nobile Under Different Epiphytic Patterns

The cultivation medium of Dendrobium nobile has an effect on the contents of its main medicinal components, but the specific mechanism is still unclear. In this study, the callus, seedlings, rhizomes, and leaves of D. nobile were sequenced for the PacBio SMRT. The 2-year-old stems were selected for the Illumina sequencing and metabolome sequencing to analyze the genetic mechanism of metabolic differences under different epiphytic patterns. As a result, a total of 387 differential genes were obtained, corresponding to 66 differential metabolites. Different epiphytic patterns can induce a series of metabolic changes at the metabolome and transcriptome levels of D. nobile, including flavonoid metabolism, purine metabolism, terpenoid backbone biosynthesis, amino acid metabolism, and alpha-linolenic acid metabolic, and related regulatory genes include ALDH2B7, ADC, EPSPS-1, SHKA, DHAPS-1, GES, ACS1, SAHH, ACS2, CHLP, LOX2, LOX2.3, and CYP74B2. The results showed that the genetic mechanism of D. nobile under various epiphytic patterns was different. In theory, the content of metabolites under the epiphytic patterns of Danxia stone is higher, which is more suitable for field cultivation.

Changes in the component sugar and immunostimulating activity of polysaccharides isolated from Dendrobium officinale in the pretreatments

BACKGROUND

To isolate polysaccharides with enhanced immunostimulatory activity from Dendrobium officinale, which is used as a herbal medicine in China and Southeast Asia, D. officinale (DO) was pretreated with organic solvents (DOOS) or puffing at 7.5 and 9.0 kg_f (7.5DO and 9DO). Hot-water extracts (DOOS-HW, 7.5DO-HW and 9DO-HW) were prepared from each pretreated DO, along with non-pretreated DO, and crude polysaccharides (DO-CP, DOOS-CP, 7.5DO-CP and 9DO-CP) were fractionated from each hot-water extract using ethanol (five volumes).

RESULTS

When their immunostimulatory activities were compared by macrophage stimulation and intestinal immune system modulation via Peyer's patches, DOOS-CP showed more potent activity than DO-CP. However, crude polysaccharides fractionated from puffed DO showed significantly lower activity than non-puffed DO and DOOS. The most active polysaccharide contained 95% or more neutral sugar, and the composition ratio of mannose and glucose was 3.0, whereas the lowest polysaccharide content was 2.0 or less. In addition, DOOS-CP was a somewhat refined fraction containing a major peak, representing a molecular weight of 250 kDa, despite being a crude polysaccharide.

CONCLUSION

These results suggest that pretreatment of D. officinale with organic solvents may enhance the immunostimulatory activity of polysaccharides and affect the mannose/glucose ratio of polysaccharides, which plays an important role in immunostimulation. © 2021 Society of Chemical Industry.

Application of Time of Flight Mass Spectrometry in the Identification of Dendrobium devonianum Paxt and Dendrobium officinale Kimura et Migo Grown in Longling Area of Yunnan, China

In this study, in order to protect the characteristic Dendrobium devonianum Paxt industry in the Longling area, and promote the healthy development of its characteristic Chinese herbal medicines in Yunnan Province, China, the identification of Dendrobium devonianum Paxt and Dendrobium officinale Kimura et Migo from Longling county was discussed using time of flight mass spectrometry. The data of 13 Dendrobium devonianum and 7 Dendrobium officinale in the Longling area were collected by TOF MS-IDA-15 MS/MS mode, and the collected data were analyzed by PCA and T-test using MarkerView software, and the difference markers were searched using the database to confirm their compound structures. In positive and negative ion modes, 3645 and 2344 peaks were detected, respectively; 64 positive ion compounds and 60 negative ion compounds, for a total of 124 compounds were identified, mainly including organic acids, polyphenols, alkaloids, amino acids and their derivatives, benzene and its derivatives, and other compounds. The score plot and loading plot analyzed by PCA show that Dendrobium devonianum and Dendrobium officinale collected in the Longling area can be effectively identified and differentiated by high-resolution mass spectrometry with the 15 different markers in positive ion mode and 17 markers in negative ion mode, respectively. The successful identification of Dendrobium devonianum and Dendrobium officinale fully demonstrates that TOF MS can be effectively used in the identification of Dendrobium and related Chinese herbal medicines with broadly application foreground.

Dendrobium officinale leaf polysaccharides ameliorated hyperglycemia and promoted gut bacterial associated SCFAs to alleviate type 2 diabetes in adult mice

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Fractions of LDOP show the hypoglycemic effect and can restore histological function of T2D mice.

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There is a difference in the anti-T2D effect between LDOP-A and LDOP-B.

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LDOP-A modulated the gut microbiota composition of T2D mice.

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LDOP-A promotes the formation of SCFAs in T2D mice, especially butyric acid.

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Compared with LDOP-B, LDOP-A shows greater potential to ameliorate T2D.

The present study aimed to explore the possible mechanisms underlying Dendrobium officinale leaf polysaccharides of different molecular weight to alleviate glycolipid metabolic abnormalities, organ dysfunction and gut microbiota dysbiosis of T2D mice. An ultrafiltration membrane was employed to separate two fractions from Dendrobium officinale leaf polysaccharide named LDOP-A and LDOP-B. Here, we present data supporting that oral administration of LDOP-A and LDOP-B ameliorated hyperglycemia, inhibited insulin resistance, reduced lipid concentration, improved β-cell function. LDOP-A with lower molecular weight exhibited improved effect on diabetes than LDOP-B, concurrent with increased levels of colonic short-chain fatty acids (SCFAs) i.e., butyrate, decreased ratio of Firmicutes to Bacteroidetes phyla, and increased abundance of the gut beneficial bacteria i.e., Lactobacillus, Bifidobacterium and Akkermansia. These results suggest that LDOP-A possesses a stronger effect in ameliorating T2D than LDOP-B which may be related to the distinct improved SCFAs levels produced by the change of intestinal flora microstructure.

Anticancer Activity of Erianin: Cancer-Specific Target Prediction Based on Network Pharmacology

Erianin is a major bisbenzyl compound extracted from Dendrobium chrysotoxum Lindl., an important traditional Chinese herb. In recent years, a growing body of evidence has proved the potential therapeutic effects of erianin on various cancers, including hepatoma, melanoma, non-small-cell lung carcinoma, myelogenous leukemia, breast cancer, and osteosarcoma. Especially, the pharmacological activities of erianin, such as antioxidant and anticancer activity, have been frequently demonstrated by plenty of studies. In this study, we firstly conducted a systematic review on reported anticancer activity of erianin. All updated valuable information regarding the underlying action mechanisms of erianin in specific cancer was recorded and summarized in this paper. Most importantly, based on the molecular structure of erianin, its potential molecular targets were analyzed and predicted by means of the SwissTargetPrediction online server (http://www.swisstargetprediction.ch). In the meantime, the potential therapeutic targets of 10 types of cancers in which erianin has been proved to have anticancer effects were also predicted via the Online Mendelian Inheritance in Man (OMIM) database (http://www.ncbi.nlm.nih.gov/omim). The overlapping targets may serve as valuable target candidates through which erianin exerts its anticancer activity. The clinical value of those targets was subsequently evaluated by analyzing their prognostic role in specific cancer using Kaplan-Meier plotter (http://Kmplot.com/analysis/) and Gene Expression Profiling Interactive Analysis (GEPIA) (http://gepia.cancer-pku.cn/). To better assess and verify the binding ability of erianin with its potential targets, molecular flexible docking was performed using Discovery Studio (DS). The valuable targets obtained from the above analysis and verification were further mapped to the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway using the Database for Annotation, Visualization and Integrated Discovery (DAVID) (http://david.abcc.ncifcrf.gov/) to explore the possible signaling pathways disturbed/regulated by erianin. Furthermore, the in silico prediction of absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties of erianin was also performed and provided in this paper. Overall, in this study, we aimed at 1) collecting all experiment-based important information regarding the anticancer effect and pharmacological mechanism of erianin, 2) providing the predicted therapeutic targets and signaling pathways that erianin might act on in cancers, and 3) especially providing in silico ADMET properties of erianin.

Assessing the geographical distribution of 76 Dendrobium species and impacts of climate change on their potential suitable distribution area in China

The geographical distribution of plant resources is of great significance for studying the origin, distribution, and evolution of species. Climate and geographical factors help shape the distribution of plant species. Dendrobium is a commonly used traditional medicine and a precious economic crop in China. Owing to the over-exploitation and increasing medicinal demand of Dendrobium species plants, systematic investigation of the geographical distribution of the plants and analysis of their potential distribution under climate change are important for protecting Dendrobium plants. We adopted DIVA-GIS to analyze the georeferenced records of 76 species of the Dendrobium species collected from 2166 herbarium records. We analyzed the eco-geographical distribution and species richness of the genus Dendrobium to simulate the distribution of current and future scenarios using MaxEnt. The results revealed the distribution of Dendrobium in 30 provinces of China, with species abundance in Yunnan, Guangxi, Guangdong, and Hainan. Our model identified the following bioclimatic variables: precipitation in the driest months and the warmest seasons, isothermality, and range of annual temperature. Among them, annual precipitation is the most crucial bioclimatic variable affecting the distribution of 16 selected Dendrobium species. The change of climate in the future will lead to an increase in habitat suitability for some Dendrobium species as follows: D. officinal 2.12%, D. hancockii by 6.00%, D. hercoglossum by 8.25%, D. devonianum by 7.71%, D. henryi by 9.40%, and D. hainanense by 13.70%. By contrast, habitat suitability will dramatically decrease for other Dendrobium species: D. chrysotoxum by 0.89%, D. chrysanthum by 12.68%, D. fimbriatum by 5.07%, D. aduncum by 11.44%, D. densiflorum by 18.47%, D. aphyllum by 8.05%, D. loddigesii by 16.45%, D. nobile by 5.41%, D. falconeri by 8.73%, and D. moniliforme by 10.61%. The reduction of these species will be detrimental to the medicinal and economic value of the genus Dendrobium. Therefore, targeted development and reasonable management strategies should be adopted to conserve these valuable resources.

Huoshanmycins A‒C, New Polyketide Dimers Produced by Endophytic Streptomyces sp. HS-3-L-1 From Dendrobium huoshanense

Three new polyketide dimers named huoshanmycins A‒C (1–3) were isolated from a plant endophytic Streptomyces sp. HS-3-L-1 in the leaf of Dendrobium huoshanense, which was collected from the Cultivation base in Jiuxianzun Huoshanshihu Co., Ltd. The dimeric structures of huoshanmycins were composed of unusual polyketides SEK43, SEK15, or UWM4, with a unique methylene linkage. Their structures were elucidated through comprehensive 1D-/2D-NMR and HRESIMS spectroscopic data analysis. The cytotoxicity against MV4-11 human leukemia cell by the Cell Counting Kit-8 (CCK8) method was evaluated using isolated compounds with triptolide as positive control (IC₅₀: 1.1 ± 0.4 μM). Huoshanmycins A and B (1, 2) displayed moderate cytotoxicity with IC₅₀ values of 32.9 ± 7.2 and 33.2 ± 6.1 μM, respectively.

Orchidaceae-Derived Anticancer Agents: A Review

Simple Summary

Orchids are commonly used in folk medicine for the treatment of infections and tumors but little is known about the actual chemical composition of these plants and their anticancer properties. In this paper, the most recent literature on orchid-derived bioactive substances with anticancer properties is reviewed. According to the published data, numerous species of orchids contain potential antitumor chemicals. Still, a relatively insignificant number of species of orchids have been tested for their bioactive properties and most of those studies were on Asian taxa. Broader research, ’including American and African species, as well as the correct identification of samples, is essential for evaluating the usefulness of orchids as a plant family with huge anticancer potential.

Abstract

Species of orchids, which belong to the largest family of flowering plants, are commonly used in folk medicine for the treatment of infections and tumors. However, little is known about the actual chemical composition of these plants and their anticancer properties. In this paper, the most recent literature on orchid-derived bioactive substances with anticancer properties is reviewed. For the assessment, previous papers on the anticancer activity of Orchidaceae published since 2015 were considered. The papers were found by exploring electronic databases. According to the available data, many species of orchids contain potential antitumor chemicals. The bioactive substances in a relatively insignificant number of orchids are identified, and most studies are on Asian taxa. Broader research on American and African species and the correct identification of samples included in the experiments are essential for evaluating the usefulness of orchids as a plant family with vast anticancer potential.

Analysis of Endophytic Bacterial Diversity From Different Dendrobium Stems and Discovery of an Endophyte Produced Dendrobine-Type Sesquiterpenoid Alkaloids

As the unique component of Dendrobium, dendrobine-type sesquiterpenoid alkaloids (DSAs) possess a variety of medicinal properties. It has been well documented that plant endophytes can in vitro synthesize secondary metabolites identical or similar to metabolites produced by their host plants. This study aimed to investigate the composition and distribution of endophytic bacteria of Dendrobium stems by Illumina MiSeq platform sequencing and cultivation-dependent methods and then to assess the potential for endophytic bacteria to produce DSAs. Results indicated that it was necessary to combine both cultivation-dependent and cultivation-independent methods to analyze the community structure of endophytic bacterial in plants comprehensively. The length of the Dendrobium stems influenced the endophytic bacterial community. The diversity and richness of endophytic bacteria in group J10_15cm of stems were the highest, which showed a significant difference from the other stem groups. However, there was no certain connection between the diversity and richness of endophytic bacteria and the content of dendrobine. It was most likely due to the influence of several specific endophytic bacteria genera, such as Sphingomonas and Rhodococcus. Athelia rolfsii, Myrothecium roridum, as pathogenic fungi, and Pectobacterium carotovorum subsp. actinidiae, as pathogenic bacteria of Dendrobium, were used to determine the antimicrobial activities. In these assays, six strains belonging to five genera showed antimicrobial activity against at least two phytopathogens. The strain BL-YJ10_15-29 (Paracoccus pueri THG-N2.35, 98.98%) showed the best antimicrobial activity against the three phytopathogens. In addition, 2 DSAs (6-hydroxydendrobine and nobilonine) were identified in the fermentation supernatant of the strain CM-YJ10_15-44 (Pseudomonas protegens CHA0, 99.24%), whereas the whole-genome analysis results further demonstrated that the precursors of the two DSAs [geranyl-PP and (E, E)-famesyl-PP] were synthesized mainly through the methyl-D-erythritol 4-phosphate pathway in this strain. This study provides new insight into the studies on the biosynthesis of DSAs and provides potential biocontrol bacteria.

PPT1 Reduction Contributes to Erianin-Induced Growth Inhibition in Oral Squamous Carcinoma Cells

The anticancer properties of erianin have been recently discovered. However, the antitumor effect of erianin in oral squamous cell carcinoma (OSCC) remains unclear. In this study, we demonstrated that erianin can hamper OSCC cells growth both in vitro and in vivo. Erianin induced obvious G2/M arrest as well as apoptosis and gasdermin E (GSDME)-dependent pyroptosis in OSCC cells. Moreover, erianin increased autophagosome formation but decreased autolysosome function. Further study indicated that erianin significantly suppressed the expression of protein-palmitoyl thioesterase 1 (PPT1) and mTOR signaling. PPT1 has been reported to be a critical regulator of cancer progression by its modulation of autophagy and mTOR signaling. According to online databases, higher expression of PPT1 has been observed in OSCC tissues and is associated with poorer patient prognosis. As overexpression of PPT1 significantly reversed erianin-induced growth inhibition in OSCC cells, we identified the importance of PPT1 reduction in erianin-induced growth suppression. With the xenograft model, we confirmed the antitumor effect of erianin in vivo. Erianin efficiently decreased the tumor sizes, together with visibly reduced expression of PPT1 and phosphorylation of mTOR in the xenograft tumor tissues. Therefore, the present study indicated that erianin may be potentially used in OSCC therapy.