Dendrobium Nobile Research Articles

Dendrobium nobile Lindl. polysaccharides improve follicular development in PCOS rats

Polycystic ovary syndrome (PCOS) is the most typical and common metabolic abnormalities in women of reproductive age. This study examined the protective effects of Dendrobium nobile Lindl. polysaccharides (DNLP) on ovarian follicular development in letrozole-induced PCOS rats and explored the underlying molecular mechanisms. The PCOS rats showed the increased body weight, serum testosterone and luteinizing hormone levels and insulin resistance. DNLP treatment reduced the body weight, serum testosterone level and insulin resistance, but failed to affect luteinizing hormone level in the PCOS rats. DNLP treatment recovered disrupted estrous cycle in the PCOS rats. DNLP treatment decreased antral follicles and increased the thickness of the granular cell layer. DNLP treatment increased the PCNA mRNA and protein expression levels in the PCOS ovarian tissues, and inhibited cell apoptosis in the PCOS ovarian tissues via regulating apoptosis-related proteins including Bax, Bcl-2 and caspase-3. In summary, this study demonstrated the protective effects of DNLP on the ovaries in the letrozole-induced PCOS rat model. DNLP exerted its protective effects via improving follicular development and inhibiting apoptosis of ovarian granular cells in PCOS rats. This study will provide experimental basis for the future clinical application of DNLP in the treatment of PCOS.

Does soaking time during disinfestation affect germination rates in Dendrobium?

Asymbiotic germination is considered an efficient and viable technique that can increase germination rates. The effect of type and concentration of disinfestants, and the exposure time to disinfestants may differ according to the plant species. Therefore, species-specific standardization of disinfestation agent and procedure is necessary to achieve optimal germination rates. The objective of this study was to determine a disinfestation methodology to increase in vitro germination rates and the early development of seedlings of Dendrobium nobile and Dendrobium phalaenopsis, using different times for seed disinfestation and different culture media. Seeds were disinfected by soaking in a 0.8% sodium hypochlorite solution for 5 or 15 min under aseptic conditions, after which seed suspensions were either washed with water or left unwashed. Next, they were seeded in culture flasks containing four different culture media (MS, ½MS, K, and VW). The flasks were then transferred to a growth room under controlled photoperiod and temperature, where they remained under an irradiance of 20 μmol m-2 s-1. Germination rates of the species were evaluated 45 days after placement in the culture flasks. A higher germination rate was observed when the seeds were triple washed, regardless of the culture medium or soaking time. Seed soaking disinfestation for 5 min is also recommended. MS and ½MS media were the most effective culture media in promoting in vitro germination of the species under study.

First Report of Leaf Black Circular Spots on Dendrobium nobile Caused by Trichoderma longibrachiatum in Guizhou Province, China

First Report of Leaf Black Circular Spots on <i>Dendrobium nobile</i> Caused by <i>Trichoderma longibrachiatum</i> in Guizhou Province, China

Four New Picrotoxane-Type Sesquiterpenes From Dendrobium nobile Lindl

Four picrotoxane-type sesquiterpenes, dendroterpene A–D (1–4), together with four known compounds (5–8), were isolated from the stems of Dendrobium nobile Lindl. Their structures were elucidated by spectroscopic analysis, X-ray diffraction analysis, analysis of the ECD data according to the Klyne's lactone sector rule, and quantum ECD calculation. Compounds 1 and 2 are two new picrotoxane-type sesquiterpenes with a new carbon skeleton containing a formamide group, which may be derived from the previously reported dendrobiumane B skeleton by the C(9)-C(11) carbon bond cleavage. Compounds 3, 5, 6, and 8 exhibited inhibitory activity against α-glycosidase. Compounds 5 and 6 were cytotoxic against SGC-7901, K562, A549, BEL-7402, and Hela cell lines.

Extraction of Polysaccharide from Dendrobium nobile Lindl. by Subcritical Water Extraction.

Subcritical water extraction (SWE) uses hot compressed water as an effective solvent for both polar and nonpolar compounds and has been developed as an environmentally benign extraction technology for natural materials. Polysaccharides as one of the main ingredients in Dendrobium plants showed obvious biological activity. Thus, SWE of polysaccharides obtained from Dendrobium nobile Lindl. was investigated in this work. The response surface methodology (RSM) was combined with a Box–Behnken design to evaluate the influence that the three independent variables had on the response. The optimal extraction conditions (determined via RSM) were 129.83 °C extraction temperature, 16.71 min extraction time, and 1.12 MPa extraction pressure. The maximum predicted polysaccharide yield was 20.67%, which corresponded well with the experiential extraction (21.88%). The polysaccharides obtained from either the stirring extraction, refluxing extraction, ultrasound extraction, or SWE methods were compared, and the extraction processes were modeled. The molecular weight, monosaccharide composition, and antioxidative activities of the polysaccharides were analyzed.

Effects of non-thermal plasma treatment on the polysaccharide from Dendrobium nobile Lindl. And its immune activities in vitro

In order to improve the hydrophilicity and immune activity of the polysaccharide from Dendrobium nobile Lindl., non-thermal plasma was used to treat the polysaccharide. It was found that the hydrophilicity of the polysaccharide plasma-treated was significantly enhanced. Infrared spectra showed that the content of OH in the molecule increased significantly, and the monosaccharide ring changed from β-pyran sugar to β-furan sugar. The detection of SEM, AFM and TEM showed that the degree of cross-linking of surface molecules increased, and the arrangement of the polysaccharide was more compact and orderly. In vitro cell tests showed that the polysaccharide plasma-treated significantly improve the phagocytosis ability of RAW264.7, and promote the secretion of cytokines TNF-α, IL-6, IL-1. However, the cell proliferation test indicated that the polysaccharide did not increase the concentration of cytokines by promoting cell proliferation. RT-PCR showed that the polysaccharide plasma-treated could promote the expression of IL-1β at the transcriptional level. These results showed that non-thermal plasma treatment can effectively enhance the hydrophilicity of the polysaccharide and enhance its immune activity in vitro. Therefore, it can be inferred that the non-thermal plasma technology can be applied to the modification of active polysaccharides and will promote active polysaccharides to work better.

The complete chloroplast genome of Dendrobium nobile, an endangered medicinal orchid from north-east India and its comparison with related Dendrobium species.

The medicinal orchid genus Dendrobium belonging to the Orchidaceae family is a huge genus comprising about 800–1,500 species. To better illustrate the species status in the genus Dendrobium, a comparative analysis of 33 available chloroplast genomes retrieved from NCBI RefSeq database was compared with that of the first complete chloroplast genome of D. nobile from north-east India based on next-generation sequencing methods (Illumina HiSeq 2500-PE150). Our results provide comparative chloroplast genomic information for taxonomical identification, alignment-free phylogenomic inference and other statistical features of Dendrobium plastomes, which can also provide valuable information on their mutational events and sequence divergence.

Dendrobium alkaloids decrease Aβ by regulating α- and β-secretases in hippocampal neurons of SD rats.

BackgroundAlzheimer’s disease (AD) is the primary cause of dementia in the elderly. The imbalance between production and clearance of amyloid β (Aβ) is a very early, often initiating factor in AD. Dendrobium nobile Lindl. alkaloids (DNLA) extracted from a Chinese medicinal herb, which have been shown to have anti-aging effects, protected against neuronal impairment in vivo and in vitro. Moreover, we confirmed that DNLA can improve learning and memory function in elderly normal mice, indicating that DNLA has potential health benefits. However, the underlying mechanism is unclear. Therefore, we further explored the effect of DNLA on neurons, which is closely related to learning and memory, based on Aβ.MethodsWe exposed cultured hippocampal neurons to DNLA to investigate the effect of DNLA on Aβ in vitro. Cell viability was evaluated by MTT assays. Proteins were analyzed by Western blot analysis.ResultsThe cell viability of hippocampal neurons was not changed significantly after treatment with DNLA. But DNLA reduced the protein expression of amyloid precursor protein (APP), disintegrin and metalloprotease 10 (ADAM10), β-site APP cleaving enzyme 1 (BACE1) and Aβ1–42 of hippocampal neurons in rats and increased the protein expression of ADAM17.ConclusionsDNLA decreases Aβ by regulating α- and β-secretase in hippocampal neurons of SD rats.

New sesquiterpenoids from the stems of Dendrobium nobile and their neuroprotective activities

Three new sesquiterpenoids, (+)-(1R,2S,3R,4S,5R,6S,9R)-3,11,12-trihydroxypicrotoxane-2(15)-lactone (1), (−)-(1S,2R,3S,4R,5S,6R,9S,12R)-3,11,13-trihydroxypicrotoxane-2(15)-lactone (2), and (+)-(1R,5R,6S,8R,9R)-8,12-dihydroxy-copacamphan-3-en-2-one (3), together with five known compounds, were isolated from the n-butanol soluble fraction of a 95% EtOH extract of the stems of Dendrobium nobile. Their structures were determined by extensive spectroscopic analysis. Particularly, to solve difficult stereochemical problems, electronic circular dichroism calculations, NMR data calculations, and a single-crystal X-ray diffraction were performed. Interestingly, compounds 1 and 2 were picrotoxinin-type sesquiterpenoids with an unusual C15,2-lactone ring. All new sesquiterpenoids (1–3) showed a significant neuroprotective activity against H2O2-induced oxidative damage in PC12 cells. Notably, at 25 and 50 μM, compounds 1 and 2 showed the best protective effects, even better than the positive control (vitamin E).

Nudol, a phenanthrene derivative from Dendrobium nobile, induces cell cycle arrest and apoptosis and inhibits migration in osteosarcoma cells.

Purpose: Osteosarcoma is the most common malignancy of the bone in children and adolescents. There is an urgent need for the development of novel drugs to treat it. Nudol(1), a phenanthrene compound from the traditional Chinese medicine, Dendrobium nobile, exhibited antiproliferative activity against osteosarcoma cells. Therefore, the aim of the present study was to investigate the role and underlying mechanism of nudol(1) as potential chemotherapy for osteosarcoma.Methods: Cell viability was determined by MTT assay. Cell-cycle phase distribution was analyzed by flow cytometry and Western blot. DAPI staining was used for morphology observation. Apoptosis was analysis via flow cytometry. The expression levels of mRNA and protein related to capase-mediated apoptotic pathway were detected by real-time PCR and western blotting. Migration was determined by wound healing assays.Results: Nudol(1) significantly decreased cell viability in several cancer cell lines. Moreover, nudol(1) caused cell cycle arrest at G2/M phase in U2OS cells, and it also induced cell apoptosis through the caspase-dependent pathway. In addition, treatment with nudol(1) suppressed the migration of U2OS cells.Conclusion: The present study, for the first time, demonstrated effects of nudol(1) on OS in vitro and the potential molecular mechanisms. Accordingly, nudol(1) might have the potential for further development as a lead compound against bone tumor.

A polysaccharide found in Dendrobium nobile Lindl stimulates calcium signaling pathway and enhances tobacco defense against TMV

A neutral polysaccharide separated from Dendrobium nobile Lindl was designated as DNPE6(4). It was structurally characterized using a combination of spectral and chemical analysis. Its average molecule weight was 99.2 kDa. The monosaccharide composition was Araf, Glcp, Galp, and Manp in a molar ratio of 2.5:0.9:0.3:0.8. Their linkage types were →1)-L-Araf-(3→, →1)-D-Glcp-(4→, →1)-D-Galp-(3→, →1)-D-Galp-(6→, →1)-D-Manp-(3, 6→, and T-D-Manp. The polysaccharide was found to have anti-TMV and anti-CMV activities for the first time in vivo. Notably, DNPE6(4) exhibited excellent protective activity against TMV. Furthermore, several proteins related to calcium signaling pathway and pathogen related proteins were up-regulated, and we also found expression levels of EDS1, ICS1, and PR1 involved in SA pathway up-regulated after DNPE6(4) treatment. In addition, some defense enzymes increased in the same condition. All these findings revealed DNPE6(4) was an elicitor to stimulate calcium signaling pathway to enhance the tobacco defense against TMV. This study therefore revealed that DNPE6(4) was a promising antiviral agent for future study.

Induction of Nrf2 pathway by Dendrobium nobile Lindl. alkaloids protects against carbon tetrachloride induced acute liver injury

Dendrobium nobile Lindl. alkaloids (DNLA), the active ingredients of Dendrobium, has been shown to possess anti-oxidative effects. The nuclear factor erythroid 2-related factor 2 (Nrf2) antioxidant signaling pathway plays a critical role in the cellular response to oxidative stress. Oxidative damage has been implicated in the mechanism of various hepatotoxins induced liver injury. The present study aimed to examine the protective effects of DNLA on CCl4-induced acute liver injury, and to explore the role of the Nrf2 pathway in the protective action of DNLA. Wild-type (WT) and Nrf2-knockout (Nrf2−/−) mice were administrated with DNLA (20 mg/kg/day, ig) for 7 days, and then challenged with CCl4 (20 μL/kg, ip). In WT mice, DNLA reduced CCl4 induced liver injury, as evidenced by the reduction in the serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), attenuation of malondialdehyde (MDA) production, and improved ultrastructural morphology in hepatocytes. However, the protective effect was diminished in Nrf2−/− mice, indicating an essential role of Nrf2 in DNLA-mediated protection over CCl4 liver injury. Furthermore, it was found that DNLA enhanced Nrf2 expression and nuclear accumulation and increased the expression of Nrf2 regulated downstream proteins. These results demonstrate that DNLA protects mice from CCl4 induced liver injury, probably through the activation of the Nrf2 signaling pathway.

Alkaloids of dendrobium nobile lindl. Altered hepatic lipid homeostasis via regulation of bile acids

Ethnopharmacological relevanceAccumulation of hepatic lipid promotes systemic metabolic dysfunction and results in fatty liver. Our previous studies have shown that the alkaloids of Dendrobium nobile Lindl. (DNLA) could regulate the lipid metabolism gene expression in livers of mice. However, the protective effects on hepatic lipid homeostasis and the underlying mechanisms are still unclear. Materials and methodsThe C57BL/6 male mice were randomly divided into four groups, including control group, model group, DNLA treatment group, and simvastatin positive control group. Mice in the control group and the other three groups were fed with control diet and high fat diet during the full course of this study, respectively. Hepatic lipid accumulation was induced by HFD in mice after 18 weeks of feeding. DNLA (15 mg/kg) and simvastatin (20 mg/kg) were administrated intragastrically in the DNLA treatment group and simvastatin positive control group for another 18 weeks, respectively. HE staining and Oil-Red-O staining of liver tissues were observed. TC and TG levels in liver were assayed. The amount of major bile acids in mice livers were quantified by UPLC-MS. Expression levels of genes were tested by the real-time PCR. ResultsThe results of HE staining and Oil-Red-O staining showed that DNLA could improve hepatic lipid homeostasis. DNLA significantly decreased liver TC and TG levels in the DNLA group. Moreover, the UPLC-MS analysis showed that DNLA did not only influence the hepatic bile acid quantity but did raise the hydrophilicity. Compared with the model group, DNLA decreased the hepatic levels of several free bile acids, including LCA, DCA, CA, and CDCA, and increased most important taurine-conjugated bile acids levels in liver, including TMCAs, TCDCA, TUDCA, and THDCA. In addition, DNLA also decreased the CA/CDCA ratio. The gene expression levels of Cyp27a1, Cyp3a11, Fxr, and Shp were up-regulated in DNLA treatment group. ConclusionDNLA may improve the hepatic abnormal lipid profile of HFD-fed mice via two pathways: (1) enhancing the taurine-conjugated bile acids which are highly hydrophilic and contribute to the excretion of cholesterol; (2) decreasing the CA/CDCA ratio which is positively related to cholesterol absorption.

Dendrobium nobile Lindl. alkaloids alleviate Mn‐induced neurotoxicity via PINK1/Parkinmediated autophagy in SH‐SY5Y cells

Chronic environmental and occupational exposure to manganese (Mn) results in a progressive neurological disorder referred to as manganism, a syndrome closely resembling Parkinson's disease (PD). The loss of dopaminergic neurons is critically involved in pathological progression of Mn‐induced manganism. Identification of molecular modulators of Mn‐induced neurotoxicity is essential to the development of neuroprotective strategies or effective treatments against Mn manganism. Mitochondrial dysfunction has been increasingly appreciated as a key determinant in Mn induced Parkinsonism. It has been known that PD‐associated mitochondrial proteins, PINK1 and parkin, regulate mitochondrial degradation in the development of neurological disorders. This study was designed to determine whether Dendrobium nobile Lindl. alkaloids (DNLA), a traditional Chinese medicinal herb extract, plays protective function over Mn‐induced neurotoxicity, and to investigate whether the modulation of PINK1/Parkin‐mediated autophagy is involved in the mechanism of DNLA‐mediated cell protection in Mn toxicity. The human dopaminergic cell line SH‐SY5Y cells were utilized as an in vitro model of Mn cytotoxicity. It was found that the treatment of the SH‐SY5Y cells with Mn resulted in concentration‐dependent cell death, accompanied by a decrease in mitochondrial respiration capacity, whereas pretreatment of cells with DNLA significantly alleviated cell toxicity induced by Mn and improved mitochondrial function. Analysis of PINK1 and Parkin expression revealed that pretreatment of the cells with DNLA significantly inhibited the Mn‐elicited decrease in the protein expression levels of PINK1 and Parkin. In addition, the Mn‐treated cells exhibited increased expression of LC3‐II and accumulation of p62, which was noticeably reversed by the pretreatment of cells with DNLA. These results demonstrate that DNLA inhibits Mn induced cytotoxicity, which may be mediated through modulating PINK1/Parkin‐mediated autophagic flux and improving mitochondrial function.Support or Funding InformationThis work was supported by grant from the National Natural Science Foundation of China (Grant No. 81460548).This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Dendrobium nobile Lindl. alkaloids decreases the level of intracellular β‐amyloid by improving impaired autolysosomal proteolysis in APP/PS1 mice

As the major degradation pathway for long‐lived proteins and organelles, macroautophagy is a decisive factor for the survival and longevity of cells. The existing evidence indicates that the disruption of substrate proteolysis in autolysosomes is the main mechanism underlying autophagy failure in Alzheimer's disease (AD). Thus, the restoration of normal lysosomal proteolysis and autophagy efficiency is a novel therapeutic strategy in the treatment of AD. In this study, 9‐month‐old APPswe/PS1ΔE9 transgenic (APP/PS1) mice were administered Dendrobium nobile Lindl. alkaloids (DNLA, 40 and 80 mg/kg) or Metformin (80 mg/kg), and age‐matched wild‐type mice were administered an isovolumic vehicle orally once a day for 4 months. The results demonstrated that DNLA significantly improved learning and memory in APP/PS1 transgenic mice in the Morris water maze. Furthermore, DNLA could increase the expression of the v‐ATPase A1 subunit to facilitate lysosomal acidification, prompt the dissociation of the cation independent‐mannose‐phosphate receptor from cathepsin (cat) D, promote the proteolytic maturation of cat D, increase the degradation of accumulated autophagic vacuoles (AVs) and β‐amyloid (Aβ) contained in the AVs, and alleviate neuronal and synaptic injury. These findings demonstrate that DNLA improves learning and memory function in APP/PS1 mice, and the mechanisms appear to be due to the promotion of intracellular Aβ degradation by increasing the protein level of v‐ATPase A1 and then improving autolysosomal acidification and proteolysis.Support or Funding InformationThis work has been supported by the National Natural Science Foundation of China (Grant No. 81473201); Fund of Key Discipline Construction of Zunyi Medical University; Science and Technology Foundation of State Administration of Traditional Chinese Medicine of Guizhou Province (QZYY2017‐016).This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Structural characterization and conformational properties of a polysaccharide isolated from Dendrobium nobile Lindl.

A water-soluble polysaccharide (JCP-40) from Dendrobium nobile Lindl. was extracted and purified. It was demonstrated as a single symmetrical peak based on HPSEC analysis and had an average molecular weight of 67.5 kDa. Combined with monosaccharide composition analysis, methylation analysis, 1D/2D NMR spectroscopy, the structural features of JCP-40 was proposed as follows: the major sugar residues of JCP-40 consisted of →4)-β-ᴅ-Manp-(1→ and →4)-β-ᴅ-Glcp-(1 → . Acetyl groups were found attached to the O-2 or O-3 positions on mannosyl residues based on NMR spectrum results. Rotational isomeric state (RIS)-Metropolis Monte Carlo method indicated that repeating unit increased from 30 to 120, the influence of Mw in this range affected chain flexibility. The conformational parameters (derived from Rg vs Mw and [η] vs Mw) from HPSEC suggested a random coil conformation for JCP-40.

Dendrobium nobile orchid in traditional medicine-A phytochemical analysis

The qualitative and quantitative analysis of the native orchid Dendrobium nobile was taken into consideration to validate the uses in traditional medicine. Methanol extracts of different parts of Dendrobium nobile reveal the presence of bioactive compounds such as, Vitamin A Aldehyde; Longifolene; 1-Heptatriacotanol; Z, Z-6, 28-Heptatriactontadien-2-One and Dendroban-12-One. The pharmaceutical properties would draw attention of the modern medical science.

Isolation, identification and confirmation of Foliar nematode, Aphelenchoides besseyi association with Dendrobium Orchid under Polyhouse condition

Dendrobium orchid, Dendrobium nobile, is one of the most widespread ornamentals. Besides durability and high keeping quality, its fragrant, waxy and variable coloured flowers are having a high market demand. Dendrobium orchid was found to be one of the favourable hosts for foliar nematode, Aphelenchoides besseyi. The cross inoculation study confirmed the association of Foliar nematode, A. besseyi in Dendrobium. The nematode was found to remain active on plants round the year under polyhouse condition with high temperature and relative humidity affecting the quantity and quality of flower appreciably.

Dendrobium nobile Lindl. Alkaloids Decreases the Level of Intracellular β-Amyloid by Improving Impaired Autolysosomal Proteolysis in APP/PS1 Mice.

As the major degradation pathway for long-lived proteins and organelles, macroautophagy is a decisive factor for the survival and longevity of cells. The existing evidence indicates that the disruption of substrate proteolysis in autolysosomes is the main mechanism underlying autophagy failure in Alzheimer’s disease (AD). Thus, the restoration of normal lysosomal proteolysis and autophagy efficiency is a novel therapeutic strategy in the treatment of AD. In this study, 9-month-old APPswe/PS1ΔE9 transgenic (APP/PS1) mice were administered Dendrobium nobile Lindl. alkaloids (DNLA, 40 and 80 mg/kg) or Metformin (80 mg/kg), and age-matched wild-type mice were administered an isovolumic vehicle orally once a day for 4 months. The results demonstrated that DNLA significantly improved learning and memory function in APP/PS1 transgenic mice in the Morris water maze. Furthermore, DNLA could increase the expression of the v-ATPase A1 subunit to facilitate lysosomal acidification, prompt the dissociation of the cation independent-mannose-phosphate receptor from cathepsin (cat) D, promote the proteolytic maturation of cat D, increase the degradation of accumulated autophagic vacuoles (AVs) and β-amyloid (Aβ) contained in the AVs, and alleviate neuronal and synaptic injury. These findings demonstrate that DNLA improves learning and memory function in APP/PS1 mice, and the mechanisms appear to be due to the promotion of intracellular Aβ degradation by increasing the protein level of v-ATPase A1 and then improving autolysosomal acidification and proteolysis.

Construction of a high-density genetic map by RNA sequencing and eQTL analysis for stem length and diameter in Dendrobium (Dendrobium nobile × Dendrobium wardianum)

Dendrobium nobile and Dendrobium wardianum are important orchids with high ornamental and medicinal values. The stem is the main medicinal and edible part, and thick and long stem is one of the breeding objectives. In this research, a population with 100 F1 individuals was constructed from a interspecific hybridization between D. nobile and D. wardianum. RNA sequencing (RNA-seq) was employed to identify a large number of SNP markers for parents and progeny. A total of 522.43Gb clean data was obtained from RNA-seq, and they were assembled into 177,052 transcripts and 66,153 unigenes. Among the 331,642 high-quality SNP markers that were detected, 132,747 were polymorphic. Finally, 9645 SNP markers were effective and used to construct a high-density integrated genetic map with 19 linkage groups, which covered a total length of 3612.12 cM with an average marker interval of 0.41 cM. The female map could be considered as the first high-density genetic map for D. nobile with 3608 cM in total length and an average marker interval of 0.41 cM. Three eQTLs related to stem length and diameter were identified. This study might build a foundation up for fine eQTL mapping and molecular marker-assisted breeding of Dendrobium.