Objective To investigate the role of environmental factor—temperature in the regulation of aging process by unc-13 and sbt-1 in Caenorhabditis elegans. Methods The lifespan, the speed of pharynx pumping, and the inte...Objective To investigate the role of environmental factor—temperature in the regulation of aging process by unc-13 and sbt-1 in Caenorhabditis elegans. Methods The lifespan, the speed of pharynx pumping, and the intestinal autofluorescence of unc-13 and sbt-1 mutants were examined at different temperature conditions. In addition, to exclude the possible influences from other factors in unc-13 and sbt-1 mutants, the dauer formation, the thermotaxis, the brood size and the population percentage of the mutants expressing hsp16.2-gfp were further investigated. Results Mutations of unc-13 and sbt-1 significantly increased the mean and the maximum lifespans of nematodes cultured at 20 oC and 25 oC, while no noticeable increase was found at 15 oC in either the mean or the maximum lifespan. Investigations on the speed of pharynx pumping and the intestinal autofluorescence suggested that at 20 oC and 25 oC, mutations of unc-13 and sbt-1 could slow the aging process and delay the accumulation of aging-related cellular damage. Meanwhile, mutations of unc-13 or sbt-1 did not affect the dauer formation or the thermotaxis to different temperatures in nematodes. In contrast, at 20 oC and 25 oC conditions, mutations of unc-13 and sbt-1 significantly decreased the brood size and the percentage of nematodes expressing hsp16.2-gfp, while no such differences were detected at 15 oC. Moreover, the thermotolerance of unc-13 and sbt-1 mutants could be greatly strengthened after the 16-h heat shock at 35 oC. Conclusion The regulation of aging by unc-13 and sbt-1 is temperature-dependent. And the alterations in reproduction capability and stress response may be associated with the formation of this temperature-dependent property.展开更多
β-amyloid (Aβ) and copper play important roles in the pathogenesis of Alzheimer’s disease (AD).However,the behavioral correlativity and molecular mechanisms of Aβ and copper toxicity have been investigated less of...β-amyloid (Aβ) and copper play important roles in the pathogenesis of Alzheimer’s disease (AD).However,the behavioral correlativity and molecular mechanisms of Aβ and copper toxicity have been investigated less often.In the present study,we investigated the interaction and toxicity of Aβ1-42 and copper in the Aβ1-42 transgenic Caenorhabditis elegans worm model CL2006.Our data show that the paralysis behavior of CL2006 worms significantly deteriorated after exposure to 10-3 mol L-1 copper ions.However,the paralysis behavior was dramatically attenuated with exposure to 10-4 mol L-1 copper ions.The exogenous copper treatment also partially changed the homeostatic balance of zinc,manganese,and iron.Our data suggest that the accumulation of reactive oxygen species (ROS) was responsible for the paralysis induced by Aβ and copper in CL2006.The ROS generation induced by Aβ and copper appear to be through sod-1,prdx-2,skn-1,hsp-60 and hsp-16.2 genes.展开更多
The O subfamily of forkhead box(FoxO) proteins is the downstream effector of the insulin-like growth factor-1/phosphoinositide 3-kinase/protein kinase B(IGF-1/PI3K/PKB) signal pathway.The objective of the present stud...The O subfamily of forkhead box(FoxO) proteins is the downstream effector of the insulin-like growth factor-1/phosphoinositide 3-kinase/protein kinase B(IGF-1/PI3K/PKB) signal pathway.The objective of the present study was to examine the expressions of three members of FoxO proteins,FoxO1,FoxO3a,and FoxO4 in the duodenum of Sprague-Dawley rats at different ages.The result demonstrated that the expression of FoxO4 in rat duodenum showed an age-dependent manner.At Day 21,there were no detectable localization and expression of FoxO4 in the duodenum,while,at Months 2 and 6,localization and expression of FoxO4 were distinct.In addition,FoxO4 staining was primarily concentrated in the cell nuclei of the lamina propria around the intestinal gland of the duodenum in 2-month-old rats,but was not detectable in the same area in 6-month-old rats.Our results showed also that although FoxO3a existed in the cytoplasm of the lamina propria at a low level at the 2-and 6-month marks,it was still not detectable at Day 21.Besides,FoxO1 was not detectable in all parts and stages.Taken together,our findings suggested that the cell-specific and age-dependent expressional patterns of FoxO4 and FoxO3a proteins in the duodenum play some roles in the development and growth performance of the rat duodenum.展开更多
基金supported by grants from the National Natural Science Foundation of China (No.30771113, 30870810)the Program for New Century Excellent Talents in Universitythe Innovative Research Program for Undergraduates in China (No. C2007052)
文摘Objective To investigate the role of environmental factor—temperature in the regulation of aging process by unc-13 and sbt-1 in Caenorhabditis elegans. Methods The lifespan, the speed of pharynx pumping, and the intestinal autofluorescence of unc-13 and sbt-1 mutants were examined at different temperature conditions. In addition, to exclude the possible influences from other factors in unc-13 and sbt-1 mutants, the dauer formation, the thermotaxis, the brood size and the population percentage of the mutants expressing hsp16.2-gfp were further investigated. Results Mutations of unc-13 and sbt-1 significantly increased the mean and the maximum lifespans of nematodes cultured at 20 oC and 25 oC, while no noticeable increase was found at 15 oC in either the mean or the maximum lifespan. Investigations on the speed of pharynx pumping and the intestinal autofluorescence suggested that at 20 oC and 25 oC, mutations of unc-13 and sbt-1 could slow the aging process and delay the accumulation of aging-related cellular damage. Meanwhile, mutations of unc-13 or sbt-1 did not affect the dauer formation or the thermotaxis to different temperatures in nematodes. In contrast, at 20 oC and 25 oC conditions, mutations of unc-13 and sbt-1 significantly decreased the brood size and the percentage of nematodes expressing hsp16.2-gfp, while no such differences were detected at 15 oC. Moreover, the thermotolerance of unc-13 and sbt-1 mutants could be greatly strengthened after the 16-h heat shock at 35 oC. Conclusion The regulation of aging by unc-13 and sbt-1 is temperature-dependent. And the alterations in reproduction capability and stress response may be associated with the formation of this temperature-dependent property.
基金supported by the National Natural Science Foundation of China (Grant No. 30870578)the National Basic Research Program of China (Grant No. 2006CB500700)funded by the US National Institutes of Health for providing nematode strains used in this work
文摘β-amyloid (Aβ) and copper play important roles in the pathogenesis of Alzheimer’s disease (AD).However,the behavioral correlativity and molecular mechanisms of Aβ and copper toxicity have been investigated less often.In the present study,we investigated the interaction and toxicity of Aβ1-42 and copper in the Aβ1-42 transgenic Caenorhabditis elegans worm model CL2006.Our data show that the paralysis behavior of CL2006 worms significantly deteriorated after exposure to 10-3 mol L-1 copper ions.However,the paralysis behavior was dramatically attenuated with exposure to 10-4 mol L-1 copper ions.The exogenous copper treatment also partially changed the homeostatic balance of zinc,manganese,and iron.Our data suggest that the accumulation of reactive oxygen species (ROS) was responsible for the paralysis induced by Aβ and copper in CL2006.The ROS generation induced by Aβ and copper appear to be through sod-1,prdx-2,skn-1,hsp-60 and hsp-16.2 genes.
基金Project supported by the National Natural Science Foundation of China (No. 30771553)the Basic Research Foundation for Science and Technology of Nanjing Agricultural University,China
文摘The O subfamily of forkhead box(FoxO) proteins is the downstream effector of the insulin-like growth factor-1/phosphoinositide 3-kinase/protein kinase B(IGF-1/PI3K/PKB) signal pathway.The objective of the present study was to examine the expressions of three members of FoxO proteins,FoxO1,FoxO3a,and FoxO4 in the duodenum of Sprague-Dawley rats at different ages.The result demonstrated that the expression of FoxO4 in rat duodenum showed an age-dependent manner.At Day 21,there were no detectable localization and expression of FoxO4 in the duodenum,while,at Months 2 and 6,localization and expression of FoxO4 were distinct.In addition,FoxO4 staining was primarily concentrated in the cell nuclei of the lamina propria around the intestinal gland of the duodenum in 2-month-old rats,but was not detectable in the same area in 6-month-old rats.Our results showed also that although FoxO3a existed in the cytoplasm of the lamina propria at a low level at the 2-and 6-month marks,it was still not detectable at Day 21.Besides,FoxO1 was not detectable in all parts and stages.Taken together,our findings suggested that the cell-specific and age-dependent expressional patterns of FoxO4 and FoxO3a proteins in the duodenum play some roles in the development and growth performance of the rat duodenum.
