Comparison of gut microbiota of healthy and diseased walking sticks, Phasmotaenia lanyuhensis.

Research on gut microbiota of phytophagous insects has shown to be important for the physiological functions of insect hosts; however, little is known about the changes in gut microbiota when they are suffering from environmental stress or pathogen infections. During rearing of Phasmotaenia lanyuhensis (Phasmatodea: Phasmatidae), sluggish locomotion was usually followed by the death of the insect with a symptom of melanization in the front part of the abdomen. Therefore, the abnormal individuals were initially classified into moribund, light- and serious-symptom based on the level of abnormal physiological circumstances and melanization. The gut microbiota of these samples were further investigated by 16S metagenomic sequencing and the differences in bacterial abundance and structure of bacterial community were analyzed. A decrease in microbiota diversity was observed in the diseased P. lanyuhensis, with the abundance of phyla Proteobacteria and Firmicute relatively higher compared to those without symptom. Interestingly, principal component analysis based on the bacterial richness was correlated to the level of melanization symptom in the diseased P. lanyuhensis, suggested the change in bacterial microbiota involved in this abnormal circumstance. However, the factor that caused the initial alternation of microbiota remains to be identified. Additionally, the lack of bacterial diversity (i.e., absence of Meiothermus and Nubsella spp.) in P. lanyuhensis might reduce the fitness for surviving. This report provided the comprehensive microbiota analysis for P. lanyuhensis and concluded that either the relative abundance or the bacterial diversity of microbiota in the insect digestive system may influence the physiological functions of phytophagous insects.

Too hard to swallow: a secret secondary defence of an aposematic insect.

Anti-predator strategies are significant components of adaptation in prey species. Aposematic prey are expected to possess effective defences that have evolved simultaneously with their warning colours. This study tested the hypothesis of the defensive function and ecological significance of the hard body in aposematic Pachyrhynchus weevils pioneered by Alfred Russel Wallace nearly 150 years ago. We used predation trials with Japalura tree lizards to assess the survivorship of 'hard' (mature) versus 'soft' (teneral) and 'clawed' (intact) versus 'clawless' (surgically removed) weevils. The ecological significance of the weevil's hard body was evaluated by assessing the hardness of the weevils, the local prey insects, and the bite forces of the lizard populations. The existence of toxins or deterrents in the weevil was examined by gas chromatography-mass spectrometry (GC-MS). All 'hard' weevils were instantly spat out after being bitten once and survived attacks by the lizards. In contrast, the 'soft' weevils were chewed and subsequently swallowed. The results were the same regardless of the presence or absence of the weevil's tarsal claws. The hardness of 'hard' Pachyrhynchus weevils was significantly higher than the average hardness of other prey insects in the same habitat and the mean bite forces of the local lizards. The four candidate compounds of the weevil identified by GC-MS had no known toxic or repellent functions against vertebrates. These results reveal that the hardness of aposematic prey functions as an effective secondary defence, and they provide a framework for understanding the spatio-temporal interactions between vertebrate predators and aposematic insect prey.

Description of an endemic and endangered new Sympetrum species (Odonata: Libellulidae) from the subtropical area of Taiwan.

Sympetrum nantouensis sp. nov. collected from Nantou, Central Taiwan, is described and figured, with remarks on its ecology and oviposition behaviour. Judging from penile structure, it is considered to belong to the infuscatum-group, whose members are defined here by penile characters. In the infuscatum-group, S. nantouensis is most similar to S. risi Bartenev, but they are probably not very closely related to each other. Sympetrum nantouensis differs from S. risi mainly in having beak-like cerci, well-lineated black and pale yellow pterothorax, and penile 4th segment with longer and apically upcurved cornua. This new species is distinct among its congeners in view of both biogeography and morphology because of its confined and peripheral existence and the odd shape of its cerci. All type specimens will be deposited at the Insect Collection of TFRI.

Effects of artificial light at night (ALAN) on gene expression of Aquatica ficta firefly larvae.

Artificial light at night (ALAN) is a major driver of firefly population declines, but its physiological effects are not well understood. To investigate the impact of ALAN on firefly development, we exposed larval Aquatica ficta fireflies to ALAN for two weeks. High larval mortality was observed in the periods of 1-68 days and 106-134 days post-treatment, which may represent the short- and long-term impacts of ALAN. We then profiled the transcriptome of larval Aquatica ficta fireflies following two weeks of ALAN exposure. A total of 1262 (1.67% out of 75777 unigenes) were differentially expressed in the treatment group: 1157 were down-regulated, and 105 were up-regulated. Up-regulated unigenes were related to regulation of hormone levels, ecdysteroid metabolic process, and response to stimulus; down-regulated unigenes were related to negative regulation of insulin receptor signaling, germ cell development, oogenesis, spermatid development, and regulation of neuron differentiation. Transcriptome results suggest that the endocrine, reproductive, and neural development of firefly larvae could be impaired by even relatively brief period of ALAN exposure. This report contributes a much-needed molecular perspective to the growing body of research documenting the fitness impacts of ALAN on bioluminescent fireflies.

Network pharmacology-based approach of novel traditional Chinese medicine formula for treatment of acute skin inflammation in silico.

Matrix metalloproteinase-9 (MMP-9) appears to play an important role in acute skin inflammation. Subantimicrobial dose of tetracycline has been demonstrated to inhibit the activity of MMP-9 protein. However, long-term use tetracycline will induce side effect. The catalytic site of MMP-9 is located at zinc-binding amino acids, His401, His405 and His411. We attempted to search novel medicine formula as MMP-9 inhibitors from traditional Chinese medicine (TCM) database by using in silico studies. We utilized high-throughput virtual screening to find which natural compounds could bind to the zinc-binding site. The quantitative structure-activity relationship (QSAR) models, which constructed by scaffold of MMP-9 inhibitors and its activities, were employed to predict the bio-activity of the natural compounds for MMP-9. The results showed that Celacinnine, Lobelanidine and Celallocinnine were qualified to interact with zinc-binding site and displayed well predictive activity. We found that celallocinnine was the best TCM compound for zinc binging sites of MMP-9 because the stable interactions were observed under dynamic condition. In addition, Celacinnine and Lobelanidine could interact with MMP-9 related protein that identified by drug-target interaction network analysis. Thus, we suggested the herbs Hypericum patulum, Sedum acre, and Tripterygium wilfordii that containing Celallocinnine, Celacinnine and Lobelanidine might be a novel medicine formula to avoid the side effect of tetracycline and increase the efficacy of treatment.

Iron depletion strategy for targeted cancer therapy: utilizing the dual roles of neutrophil gelatinase-associated lipocalin protein.

Decreasing iron uptake and increasing iron efflux may result in cell death by oxidative inactivation of vital enzymes. Applying the dual function of neutrophil gelatinase-associated lipocalin (NGAL) could achieve the goal of iron depletion in the cancer cells. Tyr106, Lys125 or Lys134 was the key binding site for NGAL protein to sequester iron-chelating siderophores. In this study, we employed all bioactive peptides in peptide databank to dock with the siderophore-binding sites of NGAL protein by virtual screening. In addition, we performed molecular dynamics (MD) simulation to observe the molecular character and structural variation of ligand-protein interaction. Glu-Glu-Lys-Glu (EEKE), Glu-Glu-Asp-Cys-Lys (EEDCK), and Gly-Glu-Glu-Cys-Asp (GEECD) were selected preliminarily by rigorous scoring functions for further investigation. GEECD was excluded due to higher binding total energy than the others. Moreover, we also excluded EEKE due to larger influence to the stability of binding residues by the information of root mean square fluctuation (RMSF) and principal component analysis (PCA). Thus, we suggested that EEDCK was the potential bioactive peptide which had been proved to inhibit malignant cells for targeted cancer therapy. Graphical Abstract Perspective drug design of occupying the siderophore-binding sites of NGAL outside the cell temporarily by a potential short peptide until NGAL enters into the cell, and releasing the siderophore-binding sites inside the cell.

Identification of tyrosinase inhibitors from traditional Chinese medicines for the management of hyperpigmentation.

The inhibition of tyrosinase is the most effective method to decrease melanin synthesis during the process of pigmentation. We aimed to find compounds from traditional Chinese medicines (TCM) that are more effective than the most commonly used tyrosinase inhibitor, arbutin. First, we employed homology modeling to construct a tyrosinase-modeled structure, and structure-based virtual screening to screen from 61,000 TCM compounds. We also adopted the following quantitative structure-activity relationship (QSAR) models for ligand-based validation: support vector machine, multiple linear regression, and Bayesian network. Molecular dynamics (MD) simulation was used to confirm the stability of ligand binding. We found that merresectine C might more effectively bind and inhibit the activity of tyrosinase than arbutin. This study provides useful evidence for the potential development of a novel non-toxic bleaching or whitening ingredient.

Insight into molecular dynamics simulation of BRAF(V600E) and potent novel inhibitors for malignant melanoma.

BRAF inhibitors have changed the standard therapeutic protocol for advanced or metastatic melanoma which harbored notorious BRAF(V600E) single mutation. However, drug resistance to BRAF inhibitors happens just like other cancer treatment. In this study, we constructed the ideal BRAF(V600E)-modeled structure through homology modeling and introduced the method of structure-based docking or virtual screening from the large compound database. Through certain methods of molecular dynamics simulation, we realized that BRAF(V600E) had quite prominent difference of molecular character or structural variation from the wild-type BRAF protein. It might confer the metamorphic character of advanced melanoma for the patients who harbored BRAF(V600E) mutation. By the methods of ligand-based quantitative structure-activity relationship and molecular dynamics simulation, we further recommend that aknadicine and 16beta-hydroxy-19s-vindolinine N-oxide from the traditional Chinese medicine are potent novel inhibitors for the management of malignant melanoma in the future.

Design of glucagon-like Peptide-1 receptor agonist for diabetes mellitus from traditional chinese medicine.

Glucagon-like peptide-1 (GLP-1) is a promising target for diabetes mellitus (DM) therapy and reduces the occurrence of diabetes due to obesity. However, GLP-1 will be hydrolyzed soon by the enzyme dipeptidyl peptidase-4 (DPP-4). We tried to design small molecular drugs for GLP-1 receptor agonist from the world's largest traditional Chinese medicine (TCM) Database@Taiwan. According to docking results of virtual screening, we selected 2 TCM compounds, wenyujinoside and 28-deglucosylchikusetsusaponin IV, for further molecular dynamics (MD) simulation. GLP-1 was assigned as the control compound. Based on the results of root mean square deviation (RMSD), solvent accessible surface (SAS), mean square deviation (MSD), Gyrate, total energy, root mean square fluctuation (RMSF), matrices of smallest distance of residues, database of secondary structure assignment (DSSP), cluster analysis, and distance of H-bond, we concluded that all the 3 compounds could bind and activate GLP-1 receptor by computational simulation. Wenyujinoside and 28-deglucosylchikusetsusaponin IV were the TCM compounds that could be GLP-1 receptor agonists.

In silico design for adenosine monophosphate-activated protein kinase agonist from traditional chinese medicine for treatment of metabolic syndromes.

Adenosine monophosphate-activated protein kinase (AMPK) acts as a master mediator of metabolic homeostasis. It is considered as a significant millstone to treat metabolic syndromes including obesity, diabetes, and fatty liver. It can sense cellular energy or nutrient status by switching on the catabolic pathways. Investigation of AMPK has new findings recently. AMPK can inhibit cell growth by the way of autophagy. Thus AMPK has become a hot target for small molecular drug design of tumor inhibition. Activation of AMPK must undergo certain extent change of the structure. Through the methods of structure-based virtual screening and molecular dynamics simulation, we attempted to find out appropriate small compounds from the world's largest TCM Database@Taiwan that had the ability to activate the function of AMPK. Finally, we found that two TCM compounds, eugenyl_beta-D-glucopyranoside and 6-O-cinnamoyl-D-glucopyranose, had the qualification to be AMPK agonist.

Drug design of cyclin-dependent kinase 2 inhibitor for melanoma from traditional Chinese medicine.

One has found an important cell cycle controller. This guard can decide the cell cycle toward proliferation or quiescence. Cyclin-dependent kinase 2 (CDK2) is a unique target among the CDK family in melanoma therapy. We attempted to find out TCM compounds from TCM Database@Taiwan that have the ability to inhibit the activity of CDK2 by systems biology. We selected Tetrahydropalmatine, Reserpiline, and (+)-Corydaline as the candidates by docking and screening results for further survey. We utilized support vector machine (SVM), multiple linear regression (MLR) models and Bayesian network for validation of predicted activity. By overall analysis of docking results, predicted activity, and molecular dynamics (MD) simulation, we could conclude that Tetrahydropalmatine, Reserpiline, and (+)-Corydaline had better binding affinity than the control. All of them had the ability to inhibit the activity of CDK2 and might have the opportunity to be applied in melanoma therapy.

Investigation of the novel lead of melanocortin 1 receptor for pigmentary disorders.

Knowing the role of MC1R in skin tanning can provide a brand new idea to resolve pigmentary disorders. α MSH has 13 amino acids and is the most essential pigmentary melanocortin responsible for melanin synthesis. One could utilize the compound library to find lead compounds by virtual screening from peptide database and traditional Chinese medicine (TCM) database@Taiwan. Computational simulation provided a convenient technology to survey potential lead. Ligand-based validation set up the reliable model for molecular dynamics simulation. Molecular dynamics simulation approved the binding affinity and stability of the peptides selected by virtual screening. Thus, we concluded that Glu-Glu-Lys-Glu (EEKE), Glu-Gly-Gly-Ser-Val-Glu-Ser (EGGSVES), and Glu-Glu-Asp-Cys-Lys (EEDCK) were potent lead peptides for MC1R to resolve pigmentary disorders.