Phytoecdysterones from Cucubalus baccifer (Caryophyllaceae)

Six phytoecdysterones have been isolated from the n-BuOH portion of Cucubalus baccifer L., a Chinese folk medicinal plant. Their structures were elucidated as ecdysterone (1), 24(28)-ecdysterone (2), 22-deoxyecdysterone (3), 25-hydroxypanuosterone (4), rubrosterone (5) and 2,22-dideoxyecdysterone 3 beta -O-beta -D-glucopyranoside (6) respectively on the basis of spectroscopic and chemical methods. Among them compound 6 was a new phytoecdysterone glycoside and 1-5 were first obtained from this plant.

Chemical Constituents of Silene jenisseensis Root

从旱麦瓶草（ＳｉｌｅｎｅｊｅｎｉｓｓｅｅｎｓｉｓＷｉｌｌｄ．）的根中分出３种化合物，根据理化常数及波谱分析鉴定了其中２个为α—菠菜甾醇葡萄糖甙（１），蜕皮甾酮（２）。这两个化合物均为首次从该植物中分得。

Pesticidal character of phytoecdysteroids from Ajuga multiflora Bunge (Labiatae) on larvae of Cryptorrhynchus lapathi L. (Coleoptera: Curculionidae)

Eight kinds of phytoecdysteroids extracted from different parts of Ajuga multiflora Bunge (Labiatae) that were collected from different places at different time were tested for killing effects on the 2-instar larvae of Cryptorrhynchus lapathi L by adding them to the artificial diet of larvae. The experimental results indicated that adding 1-3-mL phytoecdysteroids to the artificial diet could lead 58%-100% of 2-instar larvae of C. lapathi to death within 24 days. The phytoecdysteroids extracted from the whole plant of A. multiflora which was collected before flowering time were much more effective than those extracted from the plants collected at flowering and after flowering periods, and the modified mortality rate of larvae reached 65.22%, 85.07%, and 98.11% at the dosage level of 1-mL, 2-mL, and 3-mL extracts, respectively. The extract made from root of A. multiflora plant was more effective in killing efficiency than those from stem and leaves, and the average death rates of larvae were up to 100%, 98.20% and 98.32% at dosage levels of 1-mL, 2-mL, and 3-mL extracts, respectively. The killing speed of the extracted phytoecdysteroids was slower than that of triflumuron, hexaflumuron or deltamethrin emulsifiable concentrate. The mortality rate of larvae is closely related to the feeding duration on the diets containing phytoecdysteroids. Feeding on the diets with addition of phytoecdysteroids for 16 days, more than 80% of treated 2-instar larvae of C. lapathi were led to death. The killing effect of the extracts was little affected by the growth areas of A. multiflora plant and the adding way to artificial diet.

Separation and Quantitative Determination of Three Phytoecdysteroids in Rhaponticum uniflorum by High Performance Liquid Chromatograghy

An anlytical method for the separation and quantitative determination of three phytoecdysteroids in Rhaponticum uniflorum by high performance liquid chromatography has been developed.Three phytoecdysteroids,ecdysterone (Ⅰ),rha- pontisterone(Ⅱ) and turkesterone(Ⅲ) were separated and determined quantitatively by using the solvent system MeOH-H_2O(40∶60) at 242 nm with flow rate of 1.5ml/min,the operation can be completed in 10 minutes.Using the external standard method,the content of three phytoecdysteroids in the roots and aerial parts of Rhaponticum uniflorum obtained from dif- ferent localities was determined.It is proved that this method is sensitive and accurate,and with good reproducibility.

Effect of Different Size of Ground Cyanotis arachnoidea Particles on the Release of β-ecdysone

[Objective] The aim was to investigate the influence of different size of ground Cyanotis arachnoidea C.B.Clarke particles on the release of β-ecdysone.[Method] The content of β-ecdysone extracted from Cyanotis arachnoidea powders of different sizes was detected through HPLC,under the chromatographic conditions：GRACE ODS C18 column（250 mm × 4.6 mm,5 μm）,mobile phase methanol：water= 40：60（V/V）,column temperature 26 ℃,flow rate 1.0 ml/min and detection wavelength 248 nm.[Result] The extracted β-ecdysone from ultra-fine Cyanotis arachnoidea powder（particle size 10,30 and 50 μm） was as more than two folds as common powder（particle size 180 μm）.[Conclusion] The β-ecdysone in ultra-fine powder of Cyanotis arachnoidea was more easily soluble in methanol.The extraction rate of β-ecdysone was significantly higher than that of common powder.The result showed that the technology of ultra-fine pulverization markedly improved the dissolution of the β-ecdysone for increasing the cell breakage rate,and then the active ingredients could be extracted more easily.

Molt and reproduction enhancement together with hemolymph ecdysteroid elevation under eyestalk ablation in the female fiddler crab,Uca triangularis(Brachyura:Decapoda)

We present the results of eyestalk extirpation experiments performed on the fiddler crab, Uca triangularis at seasons of molting and reproduction, with a view to have a better understanding of the regulatory mechanisms of these two highly energy-demanding processes. Bilateral eyestalk ablation resulted in precocious acceleration of both molting and reproduction, irrespective of the season at which each experiment was conducted. The rate of accelerated ovarian growth, however, was maximum if the eyestalk ablation was conducted during August-January, the breeding season in the wild, or in February- May （molting-reproductive season）, wherein a section of the wild population would be engaged in molting and another section in breeding. The highest degree of precocious molt acceleration, on the other hand, was obtained during June-July when the population was primarily engaged in molting, but with no reproductive activity. The precocious oocyte maturation （due to de-eyestalking） was minimal in June--July. Significantly, the eyestalk ablation also resulted in a dramatic increase in the hemolymph ecdysteroid titer, revealing that a high ecdysteroid titer would have no restraining influence on vitellogenesis. No spawning was, however, observed among de-eyestalked females, even though their final oocyte size surpassed the size of the normal mature oocytes, implying that spawning is not exclusively under the control of eyestalk hormones. A comparative study performed on the viteUine components of the experimentals and the controls revealed that the precociously incorporated yolk under eyestalk ablation was biochemically impoverished. These results indicate that throughout the annual cycle, both the somatic and the reproductive growth of U. triangularis are under the influence of inhibitory principles from the eyestalks. It is also revealing that mere deprival of the inhibitory principles does not culminate into successful vitellogenesis. Arguably, the inhibitory influence from the eyestalks could be a prerequisite for normal healthy maturation of the oocytes and spawning.

Comparison of the Respiratory Metabolism of Juvenile Litopenaeus vannamei Cultured in Seawater and Freshwater

Litopenaeus vannamei, a euryhaline species, can be cultured at a wide range of salinities. The emergence of freshwater pond-culture ofL. vannamei is an important prelude to the continued development of shrimp culture in China. In this study, we com- pared the respiratory metabolism of juvenile L. vannamei cultured in freshwater and saltwater by measuring their oxygen consump-tion rate （OCR）, ammonium-type nitrogen excretion rate （AER） and pyruvate kinase （PK） and lactate dehydrogenase （LDH） activi-ties at different molting stages in order to physiecologically characterize juvenile L. vannamei under freshwater conditions. The re- suits showed that OCR was significantly higher in saltwater than in freshwater at all stages of molting cycle. However, variation of OCR among molting stages in saltwater was similar with that in freshwater, and the highest OCR was observed at post-molting stage. At all stages of molting cycle, AER was significantly higher in freshwater than in saltwater, and the highest was observed at post-molting stage. The activity of PK was significantly higher in saltwater than in freshwater. Conversely, the activity of LDH was higher in freshwater than in saltwater in general. Significant variation of PK and LDH activities in molting cycle was observed in saltwater and freshwater. The results indicated that aerobic metabolism of juvenile L. vannamei was more active in saltwater than in freshwater; while its protein metabolism was more active in freshwater than in saltwater.

Functional Role of Neuropeptide Leucokininll in Growth Inhibition of Red Palm Weevil Rhynchophorus ferrugineus

Peptides are known to on act to discourage the growth of insects. In this perspective, authors studied the biological and physiological effects of LeucokininlI on the growth of Red Palm Weevil through adult insect feeding of the sugar cane treated with different concentrations （0.05%, 0. I%, 0.25%, 0.4%） and biological effects on the number of eggs, the percentage of hatching, the length of the generation and the proportion of deformation, Results showed that there is a significant reduction in the number of eggs laid by the insects as the average number of eggs/female 75.7, 63.5, 59.4, 55.1 egg for each of the concentrations, respectively, compared with the average 140.2 egg in the control group, and reduction of percentages of hatching in all treatment as 71.4%, 64.6%, 70% and 71.5% respectively, compared with 79.3% of the control group. The percentage of deformations in egg densities included 44.4%, 15.4%, 22.6%, 27.8% compared to the control group. The results showed that there are a number of large deformations in the resulting larvae for different treatments. The conclusion is drawn that this study using LeucokininlI confirmed inhibition growth and caused an imbalance in the development stages of different insects due to its effect on the hormones that control molting of insects. This conclusion is furthermore apparent in the larval stage, as it appeared that Leucokininll prevents the insect from completing its life cycle. Test results using LeucokininlI are encouraging, and its future potential use in reducing Red Palm Weevil deserves broader studies. If the spread of currently known that this LeucokininlI is without prejudice to the work of the hormonal system.

Effects of Periodical Salinity Fluctuation on the Growth, Molting, Energy Homeostasis and Molting-Related Gene Expression of Litopenaeus vannamei

To determine the response of Litopenaeus vannamei to periodical salinity fluctuation, a 30-day experiment was conducted in laboratory. In this experiment, two salinity fluctuation amplitudes of 4(group S4) and 10(group S10) were designed. The constant salinity of 30(group S0) was used as the control. Levels of shrimp growth, molting frequency(MF), cellular energy status(ATP, ADP and AMP), as well as the expression of genes encoding molt-inhibiting hormone(MIH), crustacean hyperglycemic hormone(CHH), ecdysteroid-regulated protein(ERP), and energy-related AMP-activated protein kinase(AMPK) were determined. The results showed that periodical salinity fluctuation significantly influenced all indicators except MF which ranged from 13.3% in group S10 to15.4% in group S4. In comparison with shrimps cultured at the constant salinity of 30, those in group S4 showed a significant elevation in growth rate, food conversion efficiency, cellular energy status, ERP and MIH gene transcript abundance, and a significant reduction in CHH and AMPK transcript abundance(P < 0.05). However, salinity fluctuation of 10 only resulted in a significant variation in MIH and CHH gene expression when compared to the control(P < 0.05). According to our findings, L. vannamei may be highly capable of tolerating salinity fluctuation. When ambient salinity fluctuated at approx. 4, the increased MF and energy stores in organisms may aid to promoting shrimp growth.

蜕皮

戏唱到一半，童老爷却先溜了。把个十六岁的新娘，独自扔在房间里，可不是童老爷的作风。童老爷到了新娘的房间，把喜娘和丫头全支了开去。

Protective effects of 20-hydroxyecdysone on H_2 O_2-induced cytotoxicity in human neuroblastoma SH-SY5Y cells

The aim of this study was to investigate the possible protective effects and mechanisms of 20-hydroxyecdysone, an insect steroid hormone, on HEO2-induced cytotoxicity in human neuroblastoma SH-SYSY cells. Pretreatment with 20-hydroxyecdysone significantly elevated the cell viability and decreased LDH leakage in H2O2-treated SH-SY5Y cells. 20-Hydroxyecdysone also dramatically reduced malondialdehyde （MDA） contents and enhanced the superoxide dismutase （SOD） activities under oxidative stress conditions. Furthermore, 20-hydroxyecdysone pretreatment inhibited apoptosis by decreasing the Bax/Bcl-2 ratio and attenuating the activation of caspase-3. These results suggest that 20-hydroxyecdysone can protect SH-SYSY cells against H2O2-induced cytotoxicity and might potentially be used to treat neurodegenerative diseases induced by oxidative stress and anontosis.

THEPROTHORACICOSTATICPEPTIDETHATINHIBITS ECDYSTEROIDOGENESIS

Thepapergeneralizesadvancesofanewinsectbrainneuropeptide,prothoracicostaticpeptide ,which playsanimportantroleintheinsectmetamorphosis,andwasfoundandidentifiedfromsilkwormBombyxmorirecent years.Thepaperintroducesitsresearchbackground ,primarystructure,function,mutualrelationshipbetweenitand prothoracicotropichormoneaswellastheresultsofmolecularbiologyresearch.Theevaluationandexpectationofthis peptidearediscussed .

HORMONAL CONTROL OF THE VITELLOGENESIS IN THE JAPANESE OAK SILKWORM, ANTHERAEA YAMAMAI (LEPIDOPTERA : SATURNIIDAE)

Effects of ecdysteroid and juvenile hormone (JH) on vitellogenesis of the Japanese oak silkworm, Antheraea yamamai are reported in this article. After topical treatment with 20 hydroxyecdysone alone or JH analog (i.e. methoprene) alone and combined treatment with these two chemicals, vitellogenin (Vg) titers in the fat body and haemolymph at the pupal stage were mostly higher than those of the control, indicating that both ecdysteroid and JH exerted a promoting effect on the synthesis of Vg. In contrast, the Vg uptake was markedly inhibited by JH while stimulating effect of the ecdysteroid could be shown that vitellin (Vt) titer in the ovary was lower after methoprene treatments, but higher after 20 hydroxyecdyson treatments. Meanwhile, effects of these two hormones on Vg synthesis in the fat body were also tested with the incubation in vitro with Grace medium containing 3H leucine and the hormones. The results demonstrated that Vg synthesis was stimulated after treating with methoprene alone or 20 hydroxyecdysone alone and combined treating with these two chemicals, and particularly ecdysteroid had more marked positive effect. To comprehensively concluded our results, it could be regarded that ecdysteroid play the main role in the regulation of vitellogenesis for the Japanese oak silkworm.

Expression, subcellular localization and protein-protein interaction of four isoforms of EcR/USP in the common cutworm

Ecdysone receptor （EcR） and ultraspiracle （USP） form heterodimers to mediate ecdysteroid signaling during molting and metamorphosis. Various EcR/USP heterodimers have been reported. However, it is unclear what kind of EcR/USP combination is adopted by lepidopteran insects during the larval-pupal metamorphosis and whether the EcR/USP heterodimer varies among different tissues. To address these questions, two isoforms of each EcR and USP were cloned from the common cutworm, their messenger RNA expression patterns were examined by real-time quantitative polymerase chain reaction in different tissues during the larval-pupal metamorphosis and in the midgut in response to hormonal induction. Furthermore, their subcellular localization and protein-protein interaction were explored by transient expression and far-western blotting, respectively. All the four genes were significantly up-regulated in prepuae and/or pupae. The expression profiles of EcRB1 and USP1 were nearly identical to each other in the epidermis, fat body and midgut, and a similar situation also applied to EcRA and USP2. The three genes responded to 20-hydroxyecdysone （20E） induction except for USP2, and USP1 could be up-regulated by both 20E and juvenile hormone. The four proteins mainly localized in the nucleus and the nuclear localization was promoted by 20E. The protein-protein interaction between each EcR and USP was found in vitro. These results suggest that two types of EcR/USP heterodimer （EeRA/USP2 and EcRB 1/USP1） may exist simultaneously in the common cutworm, and the latter should play more important roles during the larval-pupal metamorphosis. In addition, the types of EcR/USP heterodimer do not vary in the tissues which undergo histolysis and regeneration during metamorphosis.

Juvenile hormone membrane signaling phosphorylates USP and thus potentiates 20-hydroxyecdysone action in Drosophila

Juvenile hormone(JH) and 20-hydroxyecdysone(20 E) coordinately regulate development and metamorphosis in insects. Two JH intracellular receptors, methoprene-tolerant(Met) and germ-cell expressed(Gce), have been identified in the fruit fly Drosophila melanogaster. To investigate JH membrane signaling pathway without the interference from JH intracellular signaling, we characterized phosphoproteome profiles of the Met gce double mutant in the absence or presence of JH in both chronic and acute phases.Functioning through a potential receptor tyrosine kinase and phospholipase C pathway, JH membrane signaling activated protein kinase C(PKC) which phosphorylated ultraspiracle(USP) at Ser35, the PKC phosphorylation site required for the maximal action of 20 E through its nuclear receptor complex Ec RUSP. The usp;mutant, in which Ser was replaced with Ala at position 35 by genome editing, showed decreased expression of Halloween genes that are responsible for ecdysone biosynthesis and thus attenuated 20 E signaling that delayed developmental timing. The usp;mutant also showed lower Yorkie activity that reduced body size. Altogether, JH membrane signaling phosphorylates USP at Ser35 and thus potentiates 20 E action that regulates the normal fly development. This study helps better understand the complex JH signaling network.

Amino acid compounds released by the giant freshwater prawn Macrobrachium rosenbergii during ecdysis:a factor attracting cannibalistic behaviour?

Ecdysis is a comm on phe nomenon that happe ns throughout the life phase of the giant freshwater prawn Macrobrachium rosenbergii.It is vital to better understand the correlation between cannibalism and biochemical compound that exists during the moulting process.The objective of the present study was to determine the amino acid profile released by M.rosenbergii during the ecdysis process that promotes cannibalism.To accomplish this,changes in amino acid levels(total amino acid(TAA)and free amino acid(FAA))of tissue muscle,exoskeleton,and sample water of culture medium from the moulting(E-stage)and non-moulting(C-stage)prawns were analysed using highperformanee liquid chromatography(HPLC).Comparison study revealed that among the TAA compounds,proline and sarcosine of tissues from moulting prawn were found at the highest levels.The level of FAA from water that contains moulting prawns(E-stage)was dominated by tryptophan and proline.Significant values obtained in the present study suggested that these amino acid compounds act as a chemical cue to promote cannibalism in M.rosenbergii during ecdysis.The knowledge of compositions and compounds that were released during the moulting process should be helpful for better understanding of the mechanism and chemical cues that play roles on triggering cannibalism,and also for future dietary man ipulati on to improve feeding efficie ncies and feeding man agement,which in directly impacts productivity and profitability.

Developmental changes in hemolymph ecdysteroid level and prothoracicotropic hormone activity during the fifth larval instar of the Eri silkworm, Samia cynthia ricini

Developmental changes in hemolymph ecdysteroid level, ecdysteroid synthesis by prothoracic glands （PGs） in vitro, prothoracicotropic hormone （PTTH） activity in brain extracts, and PTTH activity in the hemolymph were measured during the fifth larval instar of the Eri silkworm, Samia cynthia ricini. The changing patterns of hemolymph ecdysteroid level and ecdysteroid synthesis by laGs in vitro are similar to each other, with maximums on day 9. However, on this day, hemolymph ecdysteroid level was substantially higher than ecdysteroid synthesis by PGs in vitro suggesting a high PTTH activity in the hemolymph on day 9. Moreover, the changing pattern of PTTH activity in brain extracts is also similar to that of PTTH activity in the hemolymph, both peaking on day 9. However, on this day, activity in brain extracts was much smaller than PTTH activity in the hemolymph implying that most PTTH synthesized by the brain is secreted to the hemolymph and the brain stores a very little amount of PTTH. This study provides unique insights onto the hormonal regulation of ecdysteroid synthesis in the Eri silkworm and is useful for our future studies on signal transduction of insect neurolaelatides.

What are extreme environmental conditions and how do organisms cope with them？

Severe environmental conditions affect organisms in two major ways. The environment may be predictably severe such as in deserts, polar and alpine regions, or individuals may be exposed to temporarily extreme conditions through weather, presence of predators, lack of food, social status etc. Existence in an extreme environment may be possible, but then to breed or molt in addition can present major bottlenecks that have resulted in the evolution of hormone-behavior adaptations to cope with unpredictable events. Examples of hormone-behavior adaptations in extreme conditions include attenuated testosterone secretion because territoriality and excess courtship may be too costly when there is one opportunity to reproduce. The individual may even become insensitive to testosterone when target areas of the brain regulating reproductive behavior no longer respond to the hormone. A second example is reduced sensitivity to glucocorticoids following acute stress during the breeding season or molt that allows successful reproduction and/or a vital renewal of the integument to endure extreme conditions during the rest of the year. Reduced sensitivity could involve： （a） modulated response of the hypothalamo-pituitary-adrenal axis, （b） reduced sensitivity to high glucocorticoid levels, or （c） a combination of （a） and （b）. Moreover, corticosteroid binding proteins （CBP） buffer responses to stress by reducing the movement of glucocorticoids into target cells. Finally, intracellular enzymes （11 β-hydroxysteroid dehydrogenase and variants） can deactivate glucocorticoids entering cells thus reducing interaction with receptors. These mechanisms have important implications for climate change and increasing extremes of weather [Current Zoology 57 （3）： 363-374, 2011].