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 mechanism...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.展开更多
One new ecdysteroid, (24 R ) 24 (2 hydroxyethyl) 20 hydroxyecdysone (3), as well as three known ecdysteroids, has been isolated from Chinese herb Serratula strangulata and these compounds 1-4 showed effecti...One new ecdysteroid, (24 R ) 24 (2 hydroxyethyl) 20 hydroxyecdysone (3), as well as three known ecdysteroids, has been isolated from Chinese herb Serratula strangulata and these compounds 1-4 showed effective antioxidant activity on AAPH induced hemolysis of human RBC and Fe 2+ + cysteine induced lipid peroxidation of liver microsome.展开更多
In order to understand the composition and quantitative variation of ecdysteriods in the adults and eggs of Opogona sacchari(Bojer),an invasive alien pest,we analyzed the ecdysteroid composition and titers in the adul...In order to understand the composition and quantitative variation of ecdysteriods in the adults and eggs of Opogona sacchari(Bojer),an invasive alien pest,we analyzed the ecdysteroid composition and titers in the adult and egg of this pest.On day 4 after eclosion,the titer of ecdysteriods in the male adult was 0.080 ng/adult,much lower than 5.978 ng/adult in the female adult.During the development of ovaries,the titer of ecdysteriods was low on the first two days,and high in the late period,with the peak(10.48 ng/ovary)appearing on day 3.During the development of eggs,the titer of ecdysteriods was about 0.010 ng/egg from day 1 to day 3,and then decreased to 0.006 ng/egg on day 4.In both adults and eggs,three main components of ecdysteriods were found by identification of HPLC/RIA.They were 20-hydroxyecdysone,26-hydroxyecdysone,and an unidentified component.展开更多
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 we...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.展开更多
In order to understand the composition and quantitative variation of ecdysteriods in the pu- pae of Opogona sacchari (Bojer), a new invasive alien pest, we analyzed the pupal ecdysteroid com- position and titers in th...In order to understand the composition and quantitative variation of ecdysteriods in the pu- pae of Opogona sacchari (Bojer), a new invasive alien pest, we analyzed the pupal ecdysteroid com- position and titers in this pest. The main component of ecdysteriods in the pupae of O. sacchari is 20-hydroxyecdysone. The titre of ecdysteriods in both male pupae and female pupae get higher gradually, and then decreased slowly after reaching a peak (80 ng/pupa). The titre of ecdysteriods was about 30 ng/pupa in the later stage of pupae. The peak of male pupae appeared on the third day, but the peak of female pupae lasted from the second day to the fourth day during pupal developments. The ecdysteroid content was higher in female pupae than in male pupae during specific pupal time (the 1st, 2nd, 4th, 5th, 6th day). We also found that the titre of ec- dysteroids in posterior part of pupae was higher than in anterior part of pupae obviously.展开更多
In order to understand the composition and quantitative variation of ecdysteriods in the larvae of Opogona sacchari (Bojer), a invasive alien pest, we analyzed the larval ecdysteroid composition and titers in this pes...In order to understand the composition and quantitative variation of ecdysteriods in the larvae of Opogona sacchari (Bojer), a invasive alien pest, we analyzed the larval ecdysteroid composition and titers in this pest. The main component of ecdysteriods in the larvae of O. sacchari is 20-hydroxyecdysone, and also there is a little 26-hydroxyecdysone. The titer of ecdysteriods in the larvae from the 1st instar to the 7th instar was gotten higher gradually compared on ng ecdyster-oid/larva, but no regularity could be found about the titer if compared on ng ecdysteroid/g avoirdupois. There was only one peak of ecdysteroids (0.5475 ng/larva) showed at day 2 during the developmental time of the 6th instar larvae. However, there were two peaks appearing during the developmental time of the 7th instar larvae , one peak (0.29415 ng/larva) at day 3, another (0.214 ng/larva) at day 5.展开更多
系统梳理近十年蜕皮甾酮领域的研究现状与发展趋势,旨在明确该领域的研究热点及未来方向,为相关基础研究与应用开发提供科学参考。本研究以Web of Science、PubMed、中国知网、维普生物医药4个数据库为文献来源,检索2015~2025年间蜕皮...系统梳理近十年蜕皮甾酮领域的研究现状与发展趋势,旨在明确该领域的研究热点及未来方向,为相关基础研究与应用开发提供科学参考。本研究以Web of Science、PubMed、中国知网、维普生物医药4个数据库为文献来源,检索2015~2025年间蜕皮甾酮相关研究文献,运用CiteSpace和VOSviewer等文献计量学工具,对文献的年度发文量、国家与机构分布、核心作者、关键词及高被引文献进行系统分析,并构建知识图谱。分析结果显示,英文文献数量从2015年的7篇增加到2024年的21篇,研究聚焦于昆虫发育调控、植物来源与合成路径、药理活性等方面。中国、德国和美国是发文量最多的3个国家,约占发文量的75%。核心研究机构以河南中医药大学和河南中医药研究院为代表,多集中于中医药大学与医学院。关键词聚类显示,“20-羟基蜕皮酮”“凋亡”“蛋白合成”“含量测定”和“作用机制”为高频关键词,研究热点正从传统的昆虫发育调控逐步拓展至其在哺乳动物中的潜在药用价值,如抗氧化、抗肿瘤、降糖及促进肌肉合成等作用。综上所述,蜕皮甾酮研究已形成较为稳定的学科体系,研究热点由基础生理功能向多学科交叉延伸,展现出广阔的药用开发前景。然而,目前仍存在国际合作不足、临床研究匮乏、作用机制尚未明确等问题。同时,未来研究应加强多中心协作,深入挖掘其在疾病治疗与代谢调节等方面的作用机制,推动研究成果从实验阶段向实际应用转化。展开更多
基金Supported by the International Foundation for Science(Stockholm,Sweden)(RGA:A/3520-1)the Junior Research Fellowship,Kannur University
文摘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.
文摘One new ecdysteroid, (24 R ) 24 (2 hydroxyethyl) 20 hydroxyecdysone (3), as well as three known ecdysteroids, has been isolated from Chinese herb Serratula strangulata and these compounds 1-4 showed effective antioxidant activity on AAPH induced hemolysis of human RBC and Fe 2+ + cysteine induced lipid peroxidation of liver microsome.
基金the National Natural Science Foundation of China(Grant No.39870476)the Natural Science Foundation of Guangdong Province(Grant Nos.E039254 and 031626)the Scientific and Technological Plan of Zhuhai City(Grant No.PC20051046)
文摘In order to understand the composition and quantitative variation of ecdysteriods in the adults and eggs of Opogona sacchari(Bojer),an invasive alien pest,we analyzed the ecdysteroid composition and titers in the adult and egg of this pest.On day 4 after eclosion,the titer of ecdysteriods in the male adult was 0.080 ng/adult,much lower than 5.978 ng/adult in the female adult.During the development of ovaries,the titer of ecdysteriods was low on the first two days,and high in the late period,with the peak(10.48 ng/ovary)appearing on day 3.During the development of eggs,the titer of ecdysteriods was about 0.010 ng/egg from day 1 to day 3,and then decreased to 0.006 ng/egg on day 4.In both adults and eggs,three main components of ecdysteriods were found by identification of HPLC/RIA.They were 20-hydroxyecdysone,26-hydroxyecdysone,and an unidentified component.
文摘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.
基金This work was supported by the National Natural Science Foundation of China （Grant No. 39870476）the Natural Science Foundation of Guangdong Province （Grant Nos. E039254 ＆ 031626）the Scientific and Technological Plan of Zhuhai City （Grant No. PC20051046）.
文摘In order to understand the composition and quantitative variation of ecdysteriods in the pu- pae of Opogona sacchari (Bojer), a new invasive alien pest, we analyzed the pupal ecdysteroid com- position and titers in this pest. The main component of ecdysteriods in the pupae of O. sacchari is 20-hydroxyecdysone. The titre of ecdysteriods in both male pupae and female pupae get higher gradually, and then decreased slowly after reaching a peak (80 ng/pupa). The titre of ecdysteriods was about 30 ng/pupa in the later stage of pupae. The peak of male pupae appeared on the third day, but the peak of female pupae lasted from the second day to the fourth day during pupal developments. The ecdysteroid content was higher in female pupae than in male pupae during specific pupal time (the 1st, 2nd, 4th, 5th, 6th day). We also found that the titre of ec- dysteroids in posterior part of pupae was higher than in anterior part of pupae obviously.
基金the Natural Science Foundation of China (Grant No. 39870476)the Natural Science Foundation of Guangdong Province (Grant Nos. E039254 & 031626)the Scientific and Technological Plan of Zhuhai city (Grant No. PC20051046).
文摘In order to understand the composition and quantitative variation of ecdysteriods in the larvae of Opogona sacchari (Bojer), a invasive alien pest, we analyzed the larval ecdysteroid composition and titers in this pest. The main component of ecdysteriods in the larvae of O. sacchari is 20-hydroxyecdysone, and also there is a little 26-hydroxyecdysone. The titer of ecdysteriods in the larvae from the 1st instar to the 7th instar was gotten higher gradually compared on ng ecdyster-oid/larva, but no regularity could be found about the titer if compared on ng ecdysteroid/g avoirdupois. There was only one peak of ecdysteroids (0.5475 ng/larva) showed at day 2 during the developmental time of the 6th instar larvae. However, there were two peaks appearing during the developmental time of the 7th instar larvae , one peak (0.29415 ng/larva) at day 3, another (0.214 ng/larva) at day 5.
文摘系统梳理近十年蜕皮甾酮领域的研究现状与发展趋势,旨在明确该领域的研究热点及未来方向,为相关基础研究与应用开发提供科学参考。本研究以Web of Science、PubMed、中国知网、维普生物医药4个数据库为文献来源,检索2015~2025年间蜕皮甾酮相关研究文献,运用CiteSpace和VOSviewer等文献计量学工具,对文献的年度发文量、国家与机构分布、核心作者、关键词及高被引文献进行系统分析,并构建知识图谱。分析结果显示,英文文献数量从2015年的7篇增加到2024年的21篇,研究聚焦于昆虫发育调控、植物来源与合成路径、药理活性等方面。中国、德国和美国是发文量最多的3个国家,约占发文量的75%。核心研究机构以河南中医药大学和河南中医药研究院为代表,多集中于中医药大学与医学院。关键词聚类显示,“20-羟基蜕皮酮”“凋亡”“蛋白合成”“含量测定”和“作用机制”为高频关键词,研究热点正从传统的昆虫发育调控逐步拓展至其在哺乳动物中的潜在药用价值,如抗氧化、抗肿瘤、降糖及促进肌肉合成等作用。综上所述,蜕皮甾酮研究已形成较为稳定的学科体系,研究热点由基础生理功能向多学科交叉延伸,展现出广阔的药用开发前景。然而,目前仍存在国际合作不足、临床研究匮乏、作用机制尚未明确等问题。同时,未来研究应加强多中心协作,深入挖掘其在疾病治疗与代谢调节等方面的作用机制,推动研究成果从实验阶段向实际应用转化。
