Naringin ameliorates H_(2)O_(2)-induced oxidative damage in cells and prolongs the lifespan of female Drosophila melanogaster via the insulin signaling pathway

Naringin exists in a wide range of Chinese herbal medicine and has proven to possess several pharmacological properties.In this study,PC12,HepG2 cells,and female Drosophila melanogaster were used to investigate the antioxidative and anti-aging effects of naringin and explore the underlying mechanisms.The results showed that naringin inhibited H_(2)O_(2)-induced decline in cell viability and decreased,the content of reactive oxygen species in cells.Meanwhile,naringin prolonged the lifespan of flies,enhanced the abilities of climbing and the resistance to stress,improved the activities of antioxidant enzymes,and decreased malondialdehyde content.Naringin also improved intestinal barrier dysfunction and reduced abnormal proliferation of intestinal stem cells.Moreover,naringin down-regulated the mRNA expressions of inr,chico,pi 3k,and akt-1,and up-regulated the mRNA expressions of dilp2,dilp3,dilp5,and foxo,thereby activating autophagy-related genes and increasing the number of lysosomes.Furthermore,the mutant stocks assays and computer molecular simulation results further indicated that naringin delayed aging by inhibiting the insulin signaling(IIS)pathway and activating the autophagy pathway,which was consistent with the result of network pharmacological predictions.

Simulation of gene pyramiding in Drosophila melanogaster

Gene pyramiding has been successfully practiced in plant breeding for developing new breeds or lines in which favorable genes from several different lines were integrated. But it has not been used in animal breeding, and some theoretical investigation and simulation analysis with respect to its strategies, feasibility and efficiency are needed before it can be implemented in animals. In this study, we used four different pure lines of Drosophila melanogaster, each of which is homozygous at a specific mutant gene with a visible effect on phenotype, to simulate the gene pyramiding process and analyze the duration and population size required in different pyramiding strategies. We finally got the ideal individuals, which are homozygous at the four target genes simultaneously. This study demonstrates that gene pyramiding is feasible in animal breeding and the interaction between genes may affect the final results.

Ganoderma lucidum spore oil(GLSO),a novel antioxidant,extends the average life span in Drosophila melanogaster

In ancient China,Ganoderma lucidum was believed to be a medical fungus that could increase lifespan.Recently,pharmacologic studies have found that polysaccharide peptides and triterpenoids extracted from Ganoderma lucidum have various physiological effects as active compounds.However,the effects of spore oil isolated from Ganoderma lucidum remains unknown.In this study,the biological effects of Ganoderma lucidum spore oil(GLSO)were evaluated using a Drosophila melanogaster model.Compared with untreated groups,groups treated with GLSO had significantly longer average and maximum lifespan in both normal conditions and under oxidative stress.The activities of various antioxidant enzymes were measured to determine the antioxidant effect of GLSO.GLSO treatment markedly enhanced total superoxide dismutase(SOD)and catalase(CAT)activity and decreased levels of malondialdehyde(MDA).Further,we found dose-dependent increases in the mRNA expression of Cu,Zn-SOD,Mn-SOD,and CAT in GLSO-treated groups.These results suggest that GLSO may effectively eliminate free radicals and extend lifespan in Drosophila.Future work should investigate the value of GLSO as a functional food for the prevention of aging in larger animal models.

Factors affecting mito-nuclear codon usage interactions in the OXPHOS system of Drosophila melanogaster

Codon usage bias varies considerably among genomes and even within the genes of the same genome. In eukaryotic organisms, energy production in the form of oxidative phosphorylation （OXPHOS） is the only process under control of both nuclear and mitochondrial genomes. Although factors affecting codon usage in a single genome have been studied, this has not occurred when both interactional genomes are involved. Consequently, we investigated whether or not other factors influence codon usage of coevolved genes. We used Drosophila melanogaster as a model organism. Our χ^2 test on the number of codons of nuclear and mitochondrial genes involved in the OXPHOS system was significantly different （χ^2= 7945.16, P 〈 0.01）. A plot of effective number of codons against GC3s content of nuclear genes showed that few genes lie on the expected curve, indicating that codon usage was random. Correspondence analysis indicated a significant correlation between axis 1 and codon adaptation index （R = 0.947, P 〈 0.01） in every nuclear gene sequence. Thus, codon usage bias of nuclear genes appeared to be affected by translational selection. Correlation between axis 1 coordinates and GC content （R = 0.814, P 〈 0.01） indicated that the codon usage of nuclear genes was also affected by GC composition. Analysis of mitochondrial genes did not reveal a significant correlation between axis 1 and any parameter. Statistical analyses indicated that codon usages of both nDNA and mtDNA were subjected to context-dependent mutations.

Observation of Biological Character of Drosophila melanogaster Meigen on Cherry and Screening of Its Insecticides

Indoor rearing observation and efficacy test of insecticides were conducted in 2010 to understand the biochemical characteristics of Drosophila rnelano-gaster and high efficient insecticides against the insect pest. The results showed that D. melanogaster had preference to eight kinds of fruits with proliferation. Fe-male adults of D. melanogaster laid eggs under epidermis of cherry fruits and newly hatched larvae caused damage on fruits. When the temperatures were （ 18 ±2） ℃ and （ 23 ± 2 ） ℃, the egg stage was 2.4 - 3.0 and 1.2 - 1.8 d ; the larval stage was 11.2 - 12.2 and 5.6 - 6.5 d; the papal stage was 9.5 - 10.6 and 5.0 - 6.2 d ; one generation was 23.1 - 25.4 and 12.8 - 14.2 d, respectively. Four insecticides （ including 1% emamectin benzoate EC 3 000 times dilution, 90% crys- tal trichlorfon 1 000 times dilution, 40% phoxim EC 1 500 times dilution and 25% buprofezin WP 2 000 times dilution） had higher control effects against D. mela-nogaster, with mortalities of 85.00% - 100.00%, 96.67% - 100.00% and 100.00% after insecticide application for 1, 3 and 6 h, respectively.

Effects of SPNE on Growth,Development and Correlated Traits of Five Drosophila melanogaster Strains

Five homozygous strains of Drosophila melanogaster were used as the experimental materials and treated with SPNE （ Special Plant Nutritional Element）. D. melanogaster larvae were incubated at 18 ℃ in Drosophila culture medium with SPNE addition. The results showed that larva emergence, pupa emergence and adult emergence in SPNE treatment were earlier than that in control. SPNE treatment accelerated the growth and development, shortened the life cycle, significantly increased the quantity of offspring and slightly improved the weight of D. melanogaster, which confirmed that SPNE posed significant effects on D. melanogaster. This study laid foundation for the breeding of D. melanogaster and other insects and provided new materials and a new approach for broadening the application of SPNE.

Inhibition of foxo and minibrain in Dopaminergic Neurons Can Model Aspects of Parkinson Disease in Drosophila melanogaster

Symptoms of Parkinson Disease (PD), the second most common neurodegenerative disease, emerge due to degeneration of dopaminergic neurons. Recently, a genome wide study revealed a role for a foxo transcription factor in PD. In the model organism Drosophila melanogaster, we have attempted 1) to inhibit the sole Drosophila homologue of foxo through the directed expression of a stable inducible RNAi transgene and 2) to indirectly increase foxo transcription activity through the inhibition of the kinase minibrain (mnb), a foxo transcriptional inhibitor. To evaluate the lifetime consequences upon the flies, longevity assays and locomotion over time assays were conducted. The inhibition of foxo by foxo-RNAi decreases life span significantly when expressed under the control of Tyrosine Hydroxylase-Gal4 (TH-Gal4). The targeted expression of mnb-RNAi, in the dopaminergic neurons, with an expected loss of suppression of foxo transcriptional activity, results in a significant loss of climbing ability. Thus alteration of foxo activity, both by RNA-inhibition and by down-regulation of an inhibitor of foxo, minibrain, produces novel Drosophila models of Parkinson Disease.

Molecular toxicity and defense mechanisms induced by silver nanoparticles in Drosophila melanogaster

The widely use of silver nanoparticles(AgNPs) as antimicrobial agents gives rise to potential environmental risks. AgNPs exposure have been reported to cause toxicity in animals.Nevertheless, the known mechanisms of AgNPs toxicity are still limited. In this study, we systematically investigated the toxicity of AgNPs exposure using Drosophila melanogaster.We show here that AgNPs significantly decreased Drosophila fecundity, the third-instar larvae weight and rates of pupation and eclosion in a dose-dependent manner. AgNPs reduced fat body cell viability in MTT(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide)assays. AgNPs caused DNA damage in hemocytes and S2 cells. Interestingly, the mRNA levels of the entire metallothionein gene family were increased under AgNPs exposure as determined by RNA-seq analysis and validated by qRT-PCR, indicating that Drosophila responded to the metal toxicity of AgNPs by producing metallothioneins for detoxification. These findings provide a better understanding of the mechanisms of AgNPs toxicity and may provide clues to effect on other organisms, including humans.

Pharmacodynamic study on insomnia-curing effects of Shuangxia Decoction in Drosophila melanogaster

The present study aimed to establish a pharmacodynamic method using the py Solo software to explore the influence of freeze-dried powders of Shuangxia Decoction(SXD) on the sleep of normal Drosophila melanogaster and the Drosophila melanogaster whose sleep was divested by light. The dose-effect and the time-effect relationships of SXD on sleep were examined. The effect-onset concentration of SXD was 0.25%, the plateau appeared at the concentration of 2.5% and the total sleep time showed a downtrend when the concentration was greater than 2.5%. The sleep time was the longest on the fourth day after SXD was given. The fruit fly sleep deprivation model was repeated by light stimulation at night. The middle dosage group(2.5%) had the best insomnia-curing effect. In conclusion, using the py Solo software, an approach for the pharmacodynamics study was established with Drosophila melanogaster as a model organism to determine the insomnia-curing effects of the traditional Chinese medicine(TCM). Our results demonstrated the reliability of this method. The freeze-dried powders of SXD could effectively improve the sleep quality of Drosophila melanogaster.

Development of three Drosophila melanogaster strains with different sensitivity to volatile anesthetics

Background The mechanisms of action for volatile anesthetics remain unknown for centuries partly owing to the insufficient or ineffective research models. We designed this study to develop three strains derived from a wild-type Drosophila melanogaster with different sensitivities to volatile anesthetics, which may ultimately facilitate molecular and genetic studies of the mechanism involved. Methods Median effective doses （ED50） of sevoflurane in seven-day-old virgin female and male wild-type Drosophila melanogaster were determined. The sensitive males and females of percentile 6-10 were cultured for breeding sensitive offspring （$1）. So did median ones of percentile 48-52 for breeding median offspring （M1）, resistant ones of percentile 91-95 for breeding resistant offspring （R1）. Process was repeated through 31 generations, in the 37th generation, S37, M37 and R37 were used to determine ED5o for enflurane, isoflurane, sevoflurane, desfiurane, halothane, methoxyflurane, chloroform and trichloroethylene, then ED50 values were correlated with minimum alveolar concentration （MAC） values in human. Results From a wild-type Drosophila melanogaster we were able to breed three strains with high, median and low sevoflurane requirements. The ratio of sevoflurane requirements of three strains were 1.20：1.00：0.53 for females and 1.22：1.00：0.72 for males. Strains sensitive, median and resistant to sevoflurane were also sensitive, median and resistant to other volatile anesthetics. For eight anesthetics, ED50 values in three strains correlated directly with MAC values in human. Conclusions Three Drosophila melanogaster strains with high, median and low sensitivity to volatile anesthetics, but with same hereditary background were developed. The ED50 are directly correlated with MAC in human for eight volatile anesthetics.

Drosophila melanogaster brain invasion pathogenic Wolbachia in central nervous system of the fly

The pathogenic Wolbachia strain wMelPop rapidly over-replicates in the brain, muscles, and retina of Drosophila melanogaster, causing severe tissue degeneration and premature death of the host. The unique features of this endosymbiont make it an excellent tool to be used for biological control of insects, pests, and vectors of human diseases. To follow the dynamics of bacterial morphology and titer in the nerve cells we used transmission electron microscopy of 3-d-old female brains. The neurons and glial cells from central brain of the fly had different Wolbachia titers ranging from single bacteria to large accumulations, tearing cell apart and invading extracellular space. The neuropile regions of the brain were free of wMelPop. Wolbaehia tightly interacted with host cell organelles and underwent several morphological changes in nerve cells. Based on different morphological types of bacteria described we propose for the first time a scheme of wMelPop dynamics within the somatic tissue of the host.

Comparative phosphoproteomics reveal new candidates in the regulation of spermatogenesis of Drosophila melanogaster

The most common phenotype induced by the endosymbiont Wolbachia in in-sects is cytoplasmic incompatibility,where none or fewer progenies can be produced when Wolbachia-infected males mate with uninfected females.This suggests that some modi-fications are induced in host sperms during spermatogenesis by Wolbachia.To identify the proteins whose phosphorylation states play essential roles in male reproduction in Drosophila melanogaster,we applied isobaric tags for relative and absolute quantitation(iTRAQ)-based proteomic strategy combined with titanium dioxide(TiO2)enrichment to compare the phosphoproteome of Wolbachia-infected with that of uninfected male re-productive systems in D.melanogaster.We identified 182 phosphopeptides,defining 140 phosphoproteins,that have at least a 1.2 fold change in abundance with a P-value of<0.05.Most of the differentially abundant phosphoproteins(DAPPs)were associated with micro-tubule cytoskeleton organization and spermatid differentiation.The DAPPs included pro-teins already known to be associated with spermatogenesis,as well as many not previously studied during this process.Six genes coding for DAPPs were knocked down,respectively,in Wolbachia-free fly testes.Among them,Slmap knockdown caused the most severe dam-age in spermatogenesis,with no mature sperm observed in seminal vesicles.Immunoflu-orescence staining showed that the formation of individualization complex composed of actin cones was completely disrupted.These results suggest that Wolbachia may induce wide changes in the abundance of phosphorylated proteins which are closely related to male reproduction.By identifying phospho-modulated proteins we also provide a signifi-cant candidate set for future studies on their roles in spermatogenesis.

Wolbachia-induced expression of kenny gene in testes affects male fertility in Drosophila melanogaster

Wolbachia are Gram-negative endosymbionts that are known to cause embry-onic lethality when infected male insects mate with uninfected females or with females carrying a different strain of Wolbachia,a situation characterized as cytoplasmice incom-patibility(CD).However,the mechanism of CI is not yet fully understood,although re-cent studies on Drosophila melanogaster have achieved great progress.Here,we found that Wolbachia infection caused changes in the expressions of several immunity-related genes,including significant upregulation of kenny(key),in the testes of D.melanogaster.Overexpression of key in fly testes led to a significant decrease in egg hatch rates when these fies mate with wild-type females.Wolbachia-infected females could rescue this embryonic lethality.Furthermore,in key overexpressing testes terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling signal was significantly stronger than in the control testes,and the level of reactive oxygen species was significantly increased.Overexpression of key also resulted in alterations of some other immunity-related gene expressions,including the downregulation of Zn72D.Knockdown of Zn72D in fly testes also led to a significant decrease in egg hatch rates.These results suggest that Wolbachia might induce the defect in male host fertility by immunity-related pathways and thus cause an oxidative damage and cell death in male testes.

Protective effect of capsaicin against methyl methanesulphonate induced toxicity in the third instar larvae of transgenic Drosophila melanogaster(hsp70-lacZ)Bg9

Capsaicin(trans-8-methyl-N-vanillyl-6-nonenamide) is the main component in hot peppers, including red chili peppers, alapenos, and habanero, belonging to the genus Capsicum. Capsaicin is a potent antioxidant that interferes with free radical activities. In the present study, the possible protective effect of capsaicin was studied against methyl methanesulphonate(MMS) induced toxicity in third instar larvae of transgenic Drosophila melanogaster(hsp70-lacZ)Bg^9. The third instar was allowed to feed on the diet having different doses of capsaicin and MMS separately and in combination. The results suggested that the exposure of third instar larvae to the diet having MMS alone showed significant hsp70 expression as well as tissue DNA and oxidative damage, whereas the larvae feed on the diet having MMS and capsaicin showed a decrease in the toxic effects for 48-h of exposure. In conclusion, capsaicin showed a dose-dependent decrease in the toxic effects induced by MMS in the third instar larvae of transgenic Drosophila melanogaster.

Topological Properties of Protein-Protein and Metabolic Interaction Networks of Drosophila melanogaster

The underlying principle governing the natural phenomena of life is one of the critical issues receiving due importance in recent years. A key feature of the scale-free architecture is the vitality of the most connected nodes （hubs）. The major objective of this article was to analyze the protein-protein and metabolic interaction networks of Drosophila melanogaster by considering the architectural patterns and the consequence of removal of hubs on the topological parameter of the two interaction systems. Analysis showed that both interaction networks follow a scale-free model, establishing the fact that most real world networks, from varied situations, conform to the small world pattern. The average path length showed a two-fold and a three-fold increase （changing from 9.42 to 20.93 and from 5.29 to 17.75, respectively） for the protein-protein and metabolic interaction networks, respectively, due to the deletion of hubs. On the contrary, the arbitrary elimination of nodes did not show any remarkable disparity in the topological parameter of the protein-protein and metabolic interaction networks （average path length： 9.42±0.02 and 5.27±0.01, respectively）. This aberrant behavior for the two cases underscores the significance of the most linked nodes to the natural topology of the networks.

Variations in body melanisation, ovariole number and fecundity in highland and lowland populations of Drosophila melanogaster from the Indian subcontinent

We investigated geographical variations in three fitness-related traits （body melanisation, ovariole number and fecundity） in laboratory-reared offspring of 10 populations of Drosophila melanogaster. The populations were collected from adjacent lowland and highland localities （-80-100 km apart） in the tropical as well as subtropical regions （11.15-31.06°N） covering a linear distance about 3 000 kilometers from south to north on the Indian subcontinent. Persistence of within- as well as between-population differences at 21 ℃ suggest that observed variations in fitness-related traits have a genetic basis. Populations from higher altitudes showed consistently higher trait values （1.4-fold increase） as compared with their corresponding lowland populations. By contrast, latitudinal variations were about two-fold higher across the entire continent. Along latitude as well as altitude, population means showed higher correlation values （r 〉 0.98） between all the three fitness traits. However, on the basis of within-population analysis （assorted darker and lighter flies）, changes in body melanisation were significantly correlated with fecundity but not with ovariole number. Thus, analysis of within-population trait variability should be preferred as compared with data on population means for adaptive significance of fitness-related traits. In the present study, the role of climatic selection is evident from regression analysis with changes in annual average temperature of the sites of origin of populations along latitude as well as altitude.

Role of the ejaculatory bulb in biosynthesis of the male pheromone cis-vaccenyl acetate in Drosophila melanogaster

In Drosophila melanogaster,the male ejaculatory bulb is the site of synthesis of a male-specific pheromone,cis-vaccenyl acetate,which functions as both an attractant and an anti-aphrodisiac.This long monounsaturated acetate is structurally similar to a number of shorter gland-synthesized moth pheromones.The cell monolayer that forms the Drosophila male ejaculatory bulb wall is responsible for the production and secretion of cis-vaccenyl acetate into the seminal fluid.When dissected bulbs were incubated with sodium[14-C]-acetate(or deuterated acetate),a labeled acetate ester was synthesized.The labeled acetate ester co-migrated with cis-vaccenyl acetate in thin layer chromatography.Incubation of the abdomens of males from which the ejaculatory bulbs had been removed,or the abdomens of females,with radiolabeled acetate did not yield any acetate ester,but did yield other lipid products,including hydrocarbons.When the isolated labeled acetate ester was hydrolyzed,no radioactive vaccenol was formed.This strongly suggests that the acetyl group is incorporated via a transacetylation reaction,but that the vaccenyl moiety is not synthetized in the blub.The transacetylation enzyme activity was localized in the microsomal subfraction of the bulb homogenate,and its affinity for vaccenol was not very different from that reported for monounsaturated alcohol substrates in moths.

Effect of copper on the development, protein and esterase isozymes of Drosophila melanogaster

Copper is an important ingredient in fungicides,which are used for many economic plants.However,there is concern about the side-effects of copper-based fungicides due to their potential to affect beneficial mites.The purpose of the present paper was to investigate the effects of copper on the development of the fruit fly,Drosophila melanogaster.It was found that higher doses of copper significantly prolonged the developmental time of the fruit flies,especially during the larval stages.When 320 mg L-1 copper-contaminated food was used,most of the larvae died when they were small and before the pupal stage.The protein contents and esterase isozymes extracted from the larvae changed according to the doses of copper.The small-molecular-weight protein bands gradually became weaker or were lost as the copper levels increased.However,low doses of copper stimulated a stronger expression of a few proteins.These results indicate that low doses of copper generally have no lethal effects on D.melanogaster because a specific group of genes,which encode specific proteins,are probably activated in order to withstand the onslaught of stressful conditions.At high doses of copper in food(e.g.320 mg L-1),fly development and viability are significantly affected.

Effect of Curcumin on Aged Drosophila Melanogaster:A Pathway Prediction Analysis

Objective： To re-analyze the data published in order to explore plausible biological pathways that can be used to explain the anti-aging effect of curcumin. Methods： Microarray data generated from other study aiming to investigate effect of curcumin on extending lifespan of Drosophila melanogaster were further used for pathway prediction analysis. The differentially expressed genes were identified by using GeneSpdng GX with a criterion of 3.0-fold change. Two Cytoscape plugins including BisoGenet and molecular complex detection （MCODE） were used to establish the protein-protein interaction （PPI） network based upon differential genes in order to detect highly connected regions. The function annotation clustering tool of Database for Annotation, Visualization and Integrated Discovery （DAVID） was used for pathway analysis. Results： A total of 87 genes expressed differentially in D. melanogaster treated with curcumin were identified, among which 50 were up-regulated significantly and 37 were remarkably down-regulated in D. melanogaster treated with curcumin. Based upon these differential genes, PPI network was constructed with 1,082 nodes and 2,412 edges. Five highly connected regions in PPI networks were detected by MCODE algorithm, suggesting anti-aging effect of curcumin may be underlined through five different pathways including Notch signaling pathway, basal transcription factors, cell cycle regulation, ribosome, Wnt signaling pathway, and p53 pathway. Conclusion： Genes and their associated pathways in D. rnelanogaster treated with anti-aging agent curcumin were identified using PPI network and MCODE algorithm, suggesting that curnumin may be developed as an alternative therapeutic medicine for treating aging-associated diseases.

Ontogeny of Drosophila melanogaster female sex-appeal and cuticular hydrocarbons

The chemical communication system in Drosophila melanogaster Meigen,1830 plays a major role in courtship and consists of the male-specific cis-Vaccenyl acetate and sex-specific contact pheromones,cuticular hydrocarbons(CHC),which build up during ontogeny(first 4 days).They replace longer CHCs,common to both sexes and present only after the imaginal eclosion.A detailed quantitative description of the evolution of cuticular unsaturated hydrocarbons with age is presented here for males and females of different D.melanogaster strains,which have been bred in well controlled environments.Monoenes appear in both sexes at around 12 h,before female dienes.The present paper argues that this is likely linked to the switching on of a new set of genes.Ecdysone,which is more abundant in females than in males during this critical period,might control this switch.Parallel behavioral studies show that whereas female of all ages trigger early mature male courtship steps like wing vibration,only females older than 1 day trigger late courtship steps like attempted copulation.This supports the hypothesis that late male courtship steps might be triggered by the CHCs,which build up after this age,especially female-specific(Z,Z)-7,11-and(Z,Z)-5,9-dienes.