Dendrobium species regulate energy homeostasis in neurodegenerative diseases: a review

Brain energy homeostasis is a vital physiological function in maintaining a balanced internal metabolic environment.The impairment of energy homeostasis is recognized as a key pathophysiological basis for brain metabolic disorders and related neurodegenerative diseases.Dendrobium species(‘Shihu’in Chinese)such as D.officinale,D.huoshanense,D.nobile,D.chrysanthum,D.loddigesii,D.moniliforme,D.gratiosissimum,D.candidum and D.caulis are widely used as traditional Chinese medicines/nutraceuticals to control and treat neurodegenerative disorders.These dietary herbs and their derived compounds possess a variety of biological properties,such as suppression of oxidative stress and neuroinflammation,regulation of energy homeostasis mainly through improving brain mitochondria function,insulin signaling and lipid metabolism.Furthermore,they reduce neurotoxicity,alleviate brain injury and neuropathy,and prevent neurodegenerative conditions including stroke,Alzheimer’s disease,Parkinson’s disease,and Huntington’s disease in humans and/or rodents.Moreover,the nutraceuticals from Dendrobium species promote gut health and aid digestion,which appear to be associated with beneficial effects on brain energy homeostasis.Based on the above-mentioned health benefits associated with Dendrobium species,this work reviews their nutraceutical role in neurodegenerative disorders and further suggests the need to elucidate mechanisms of the underlying molecular actions.

Evaluation of Cold Tolerance of Different Dendrobium Species in North China

T o investigate cold tolerance of different cultivars and species in Dendrobium Sw. in North China, 8 strains of Dendrobium officinal and other 5 Dendrobium species were used to compare their cold-hardiness index in this study. The content of electrolyte leakage was increasing in Dendrobium Sw. as the temperature decreasing, while the content of peroxidase(POD) activity and the soluble sugar showed a rising trend before a downward trend. Besides, external morphology was another evaluation standard of cold tolerance. Thus, there was a significant difference between Dendrobium officinal and other Dendrobium species in the cold tolerance, and their cold tolerance capacity was as follows: s1 > s100 >s13 > 1301 > s300 > Dendrobium nobile > s126 > s145 > s95 > Dendrobium lindleyi > Dendrobium chrysotoxum > Dendrobium thyrsiflorum > Dendrobium lohohense.

The Relationship Between Stomatal Movement and Light Intensity Gradient in Three Dendrobium Species Compared with Typical CAM Plants

There is a close relationship between crassulacean acid metabolism and drought tolerance,and a great number of landscape plants which consume less water are necessary to build economic garden.In order to provide the basis for selecting drought-tolerant landscape plants,five species of plants were employed,including Dendrobium chrysotoxum,D.nobile,D.primulinum,Kalanchoblossfeldiana and K.daigremontiana.Exposed to different intensities of light,various samples were collected.The slices were prepared via different techniques.Stomatal movements and stomatal complex structures were observed by scanning electronic microscope and confocal laser scanning microscope.The results indicated that the slices made rapidly from fresh leaves were conductive to inspecting actual stomatal movements and stomatal complex structures as soon as possible.It was found that the stomatal movement of K.daigremontiana,K.blossfeldiana and D.primulinum displayed typical characteristics of crassulacean acid metabolism,while that of D.chrysotoxum and D.nobile did not exhibited obvious characteristics of crassulacean acid metabolism.

The large single-copy(LSC) region functions as a highly effective and efficient molecular marker for accurate authentication of medicinal Dendrobium species

Having great medicinal values,Dendrobium species of"Fengdou"(DSFs)are a taxonomically complex group in Dendrobium genus including many closely related and recently diverged species.Traditionally used DNA markers have been proved to be insufficient in authenticating many species of this group.Here,we investigated 101 complete plastomes from 23 DSFs,comprising 72 newly sequenced and 29 documented,which all exhibited well-conserved genomic organization and gene order.Plastomewide comparison showed the co-occurrence of single nucleotide polymorphisms(SNPs)and insertions/deletions(indels),which can be explained by both the repeat-associated and indel-associated mutation hypotheses.Moreover,guanine-cytosine(GC)content was found to be negatively correlated with the three divergence variables(SNPs,indels and repeats),indicating that GC content may reflect the level of the local sequence divergence.Our species authentication analyses revealed that the relaxed filtering strategies of sequence alignment had no negative impact on species identification.By assessing the maximum likelihood(ML)trees inferred from different datasets,we found that the complete plastome and large single-copy(LSC)datasets both successfully identified all 23 DSFs with the maximum bootstrap values.However,owing to the high efficiency of LSC in species identification,we recommend using LSC for accurate authentication of DSFs.