Objective Age-related diseases, including neurodegenerative diseases, are associated with oxidative stress and lipid peroxidation, and increase the levels of cholesterol auto-oxidation products such as 7β-hydroxychol...Objective Age-related diseases, including neurodegenerative diseases, are associated with oxidative stress and lipid peroxidation, and increase the levels of cholesterol auto-oxidation products such as 7β-hydroxycholesterol(7β-OHC). Thus, it is imperative to identify agents that can prevent 7β-OHC-induced side-effects. Methods We evaluated the potential protective effects of Carpobrotus edulis ethanol-water extract(EWe) on murine oligodendrocytes(158 N) cultured in the absence or presence of 7β-OHC(20 μg/mL, 24 h). The cells were incubated with EWe(20-200 μg/mL) 2 h before 7β-OHC treatment. Mitochondrial activity and cell growth were evaluated with the MTT assay. Photometric methods were used to analyze antioxidant enzyme [catalase(CAT) and glutathione peroxidase(GPx)] activities and the generation of lipid and protein oxidation products [malondialdehyde(MDA), conjugated diene(CD), and carbonylated proteins(CPs)]. Results Treatment with 7β-OHC induced cell death and oxidative stress(reflected by alteration in CAT and SOD activities). Overproduction of lipid peroxidation products(MDA and CDs) and CPs was also reported. The cytotoxic effects associated with 7β-OHC were attenuated by 160 μg/mL of EWe of C. edulis. Cell death induced by 7β-OHC treatment was ameliorated, GPx and CAT activities were restored to normal, and MDA, CD, and CP levels were reduced following C. edulis extract treatment. Conclusion These data demonstrate the protective activities of C. edulis EWe against 7β-OHC-induced disequilibrium in the redox status of 158 N cells, indicative of the potential role of this plant extract in the prevention of neurodegenerative diseases.展开更多
Aims Clonal growth is associated with invasiveness in introduced plant species,but few studies have compared invasive and noninvasive introduced clonal species to investigate which clonal traits may underlie invasiven...Aims Clonal growth is associated with invasiveness in introduced plant species,but few studies have compared invasive and noninvasive introduced clonal species to investigate which clonal traits may underlie invasiveness.To test the hypothesis that greater capacity to increase clonal growth via physiological integration of connected ramets increases invasiveness in clonal plants,we compared the effects of severing connections on accumulation of mass in the two species of the creeping,succulent,perennial,herbaceous genus Carpobrotus that have been introduced on sand dunes along the Pacific Coast of northern California,the highly invasive species Carpobrotus edulis and the co-occurring,noninvasive species Carpobrotus chilensis.Methods Pairs of ramets from four mixed populations of the species from California were grown in a common garden for 3 months with and without severing the stem connecting the ramets.To simulate the effect of clones on soils in natural populations,the older ramet was grown in sand amended with potting compost and the younger in sand alone.Important Findings Severance decreased net growth in mass by~60%in C.edulis and~100%in C.chilensis,due mainly to the negative effect of severance on the shoot mass of the younger ramet within a pair.Contrary to the hypothesis,this suggests that physiological integration increases growth more in the less invasive species.However,severance also decreased allocation of mass to roots in the older ramet and increased it in the younger ramet in a pair,and the effect on the younger ramet was about twice as great in C.edulis as in C.chilensis.This indicates that the more invasive species shows greater phenotypic plasticity in response to physiological integration,in particular greater capacity for division of labor.This could contribute to greater long-term growth and suggests that the division of labor may be a trait that underlies the association between clonal growth and invasiveness in plants.展开更多
Aims Carpobrotus edulis(L.)N.E.Br.is known to invade many coastal ecosystems around the world,and it has been considered as one of the most severe threats to numerous terrestrial plant communi-ties.Therefore,the study...Aims Carpobrotus edulis(L.)N.E.Br.is known to invade many coastal ecosystems around the world,and it has been considered as one of the most severe threats to numerous terrestrial plant communi-ties.Therefore,the study of the relationships between life-history traits that may favour its invasiveness and the invasibility of the environments is necessary to improve our knowledge about inva-sion success.In this research,we specifically tested the effects of physiological integration in genotypes from contrasting habitats,where the importance of integration is expected to differ.Thus,the main objective of this work was to detect the presence of adaptive plasticity in the capacity for clonal integration in this aggressive invader.Methods In a greenhouse experiment,we compared the performance,in terms of growth and photochemical efficiency,of two C.edulis ecotypes.Connected and severed ramet pairs from coastal sand dunes and rocky coast habitats were grown in substrates of different quality and heterogeneity.Important Findings Our study clearly indicates that clonal integration improves growth and photosynthetic efficiency in the aggressive invader C.edulis.Two differ-ent aspects of clonal integration determine site-specific strategies in this species in order to optimize its successful propagation in a particular habitat.We demonstrated that the adaptation of C.edulis to local envi-ronments has led to a differential selection of two complex clonal traits associated with the capacity for clonal integration.In patchy sand dunes,C.edulis has evolved ecotypes with ramets highly plastic in patterns of biomass allocation,which allows ramets to specialize in the acquisi-tion of the resource that is locally most abundant,i.e.,a spatial division of labour among ramets.However,in the harsher rocky coast habitats,local adaptation produced highly integrated ecotypes,where resource sharing is not combined with a specialization of resource acquisition.展开更多
Aims One of the key traits associated with clonal growth in plants is the capacity for physiological integration,which allows resource sharing between connected ramets within a clonal system.Resource transport is expe...Aims One of the key traits associated with clonal growth in plants is the capacity for physiological integration,which allows resource sharing between connected ramets within a clonal system.Resource transport is expected to occur following a source–sink relationship:from ramets established in rich patches to ramets growing in poor patches.However,some experiments have shown that acropetal transport(from basal to apical modules)usually exceeds basipetal transport(from apical to basal ramets).In this study,we aimed to determine the resource transport directionality in physiologically integrated modules of the invader Carpobrotus edulis.Methods We conducted two manipulative experiments under common garden conditions that studied the effect of different nutrient levels located at different positions(basal,medial and apical)on connected and disconnected clonal systems of C.edulis.We compared the biomass partitioning patterns and final biomass of ramets to elucidate whether the effect of physiological integration is affected by the directionality of the resource transport.Important Findings Results indicate a prevalent acropetal transport of resources in C.edulis,with a developmentally programmed division of labor where basal ramets were specialized in obtaining soil-based resources and apical ramets specialized in aboveground growth.This biomass partitioning pattern was not affected by the nutrient conditions in which basal or apical ramets were growing,although the highest benefit was achieved by apical ramets growing under the most stressed conditions.This developmentally programmed division of labor is expected to increase the lateral growth of C.edulis,and therefore could have meaningful implications for the expansion of this invasive species.展开更多
Aims Coastal areas,and in particular coastal dunes,are ecosystems strongly affected by the invasion of alien plants.However,few attempts have ever been made to quantify alien species incidence in different communities...Aims Coastal areas,and in particular coastal dunes,are ecosystems strongly affected by the invasion of alien plants.However,few attempts have ever been made to quantify alien species incidence in different communities along the coastal zonation.This work aims to analyze the distribution of alien plants along the coastal zonation of sandy shores on the Tyrrhenian coast,addressing specifically differences among plant communities in abundance of alien plants.Methods The study was performed on recent dunes(Holocene)of the central western coast of Italy.We selected dune landscapes where invasion processes were particularly evident.Vegetation plots were randomly sampled and through cluster analysis,we identified six plant communities corresponding to the typical zonation described for the Tyrrhenian sandy coast of Central Italy.We evaluated and compared frequency and abundance of invasion in these different communities.Further,we investigated how propagule pressure(measured using as proxy human structures)contributed to the observed invasion patterns.Important Findings We found a relatively low total number of aliens but also a differential distribution pattern and strong abundance of some of the aliens in specific sectors of the vegetation zonation.The perennial community of transition dunes appears most affected by invasion processes,related almost exclusively to the frequent and widespread Carpobrotus aff.acinaciformis.This alien species reaches high cover values,apparently lowering cover of native species of transition dune plant communities.Higher levels of invasion in the transition dune can be partially explained because of greater propagule pressure in this section of the dune profile.Our findings thus have important conservation and management implications since transition dune communities with Crucianella maritima are rare and protected(sensu Habitat 92/43/EEC Directive)along the entire Italian coast.展开更多
Coastal dunes represent priority habitats for conservation due to the provision of valuable ecosystem services such as land protection,water supply or biodiversity conservation.Soil microbial communities are of crucia...Coastal dunes represent priority habitats for conservation due to the provision of valuable ecosystem services such as land protection,water supply or biodiversity conservation.Soil microbial communities are of crucial importance to maintain plant diversity due to harsh environmental conditions,water limitation and nutrient scarcity.Invasive alien plants represent a major threat to ecosystem conservation.Here,we explored different impacts of Carpobrotus edulis,a succulent plant invading coastal areas worldwide,on the function and structure of bacterial communities.Sand represents a challenging substrate due to low organic matter content and limited microbial activity.We optimized bacterial extraction for functional evaluation before assessing ecosystem impacts produced by C.edulis.We compared 12 extracting procedures combining different soil storage,sample amount and extracting solutions on the functional activity of sand communities through the community-level physiological profile.We further explored the function(using Biolog Ecoplates)and structure[using polymerase chain reaction–denaturing gradient gel electrophoresis(PCR-DGGE)]of bacterial communities from dunes invaded by C.edulis.Saline solution consistently increased bacterial cells detected by cytometry(P≤0.001).Principal component analysis suggested a limited temporal framework(0–24 h)in which community function can be explored without significant alterations in C substrate consumption.Changes under C.edulis invasion exhibited a different pattern of C substrate utilization comparing native and non-native zones(interspecific),but also between native zones(intraspecific),suggesting that functional impacts are site-dependent.Complementary,results obtained from PCR-DGGE indicated that the bacterial community structure of native dunes significantly differed from dunes invaded by C.edulis.展开更多
文摘Objective Age-related diseases, including neurodegenerative diseases, are associated with oxidative stress and lipid peroxidation, and increase the levels of cholesterol auto-oxidation products such as 7β-hydroxycholesterol(7β-OHC). Thus, it is imperative to identify agents that can prevent 7β-OHC-induced side-effects. Methods We evaluated the potential protective effects of Carpobrotus edulis ethanol-water extract(EWe) on murine oligodendrocytes(158 N) cultured in the absence or presence of 7β-OHC(20 μg/mL, 24 h). The cells were incubated with EWe(20-200 μg/mL) 2 h before 7β-OHC treatment. Mitochondrial activity and cell growth were evaluated with the MTT assay. Photometric methods were used to analyze antioxidant enzyme [catalase(CAT) and glutathione peroxidase(GPx)] activities and the generation of lipid and protein oxidation products [malondialdehyde(MDA), conjugated diene(CD), and carbonylated proteins(CPs)]. Results Treatment with 7β-OHC induced cell death and oxidative stress(reflected by alteration in CAT and SOD activities). Overproduction of lipid peroxidation products(MDA and CDs) and CPs was also reported. The cytotoxic effects associated with 7β-OHC were attenuated by 160 μg/mL of EWe of C. edulis. Cell death induced by 7β-OHC treatment was ameliorated, GPx and CAT activities were restored to normal, and MDA, CD, and CP levels were reduced following C. edulis extract treatment. Conclusion These data demonstrate the protective activities of C. edulis EWe against 7β-OHC-induced disequilibrium in the redox status of 158 N cells, indicative of the potential role of this plant extract in the prevention of neurodegenerative diseases.
基金This work was supported by the Spanish Ministry of Economy and Competitiveness(Grant CGL2013-44519-R to S.R.R.).
文摘Aims Clonal growth is associated with invasiveness in introduced plant species,but few studies have compared invasive and noninvasive introduced clonal species to investigate which clonal traits may underlie invasiveness.To test the hypothesis that greater capacity to increase clonal growth via physiological integration of connected ramets increases invasiveness in clonal plants,we compared the effects of severing connections on accumulation of mass in the two species of the creeping,succulent,perennial,herbaceous genus Carpobrotus that have been introduced on sand dunes along the Pacific Coast of northern California,the highly invasive species Carpobrotus edulis and the co-occurring,noninvasive species Carpobrotus chilensis.Methods Pairs of ramets from four mixed populations of the species from California were grown in a common garden for 3 months with and without severing the stem connecting the ramets.To simulate the effect of clones on soils in natural populations,the older ramet was grown in sand amended with potting compost and the younger in sand alone.Important Findings Severance decreased net growth in mass by~60%in C.edulis and~100%in C.chilensis,due mainly to the negative effect of severance on the shoot mass of the younger ramet within a pair.Contrary to the hypothesis,this suggests that physiological integration increases growth more in the less invasive species.However,severance also decreased allocation of mass to roots in the older ramet and increased it in the younger ramet in a pair,and the effect on the younger ramet was about twice as great in C.edulis as in C.chilensis.This indicates that the more invasive species shows greater phenotypic plasticity in response to physiological integration,in particular greater capacity for division of labor.This could contribute to greater long-term growth and suggests that the division of labor may be a trait that underlies the association between clonal growth and invasiveness in plants.
基金Financial support for this study was provided by the Spanish Ministry of Economy and Competitiveness and the European Regional Development’s Fund(ERDF)(grants Ref.CGL2013-44519-R awarded to S.R.R.and Ref.CGL2013-48885-C2-2-R awarded to R.R.)This is a contribution from the Alien Species Network(Ref.R2014/036-Xunta de Galicia,Autonomous Government of Galicia).
文摘Aims Carpobrotus edulis(L.)N.E.Br.is known to invade many coastal ecosystems around the world,and it has been considered as one of the most severe threats to numerous terrestrial plant communi-ties.Therefore,the study of the relationships between life-history traits that may favour its invasiveness and the invasibility of the environments is necessary to improve our knowledge about inva-sion success.In this research,we specifically tested the effects of physiological integration in genotypes from contrasting habitats,where the importance of integration is expected to differ.Thus,the main objective of this work was to detect the presence of adaptive plasticity in the capacity for clonal integration in this aggressive invader.Methods In a greenhouse experiment,we compared the performance,in terms of growth and photochemical efficiency,of two C.edulis ecotypes.Connected and severed ramet pairs from coastal sand dunes and rocky coast habitats were grown in substrates of different quality and heterogeneity.Important Findings Our study clearly indicates that clonal integration improves growth and photosynthetic efficiency in the aggressive invader C.edulis.Two differ-ent aspects of clonal integration determine site-specific strategies in this species in order to optimize its successful propagation in a particular habitat.We demonstrated that the adaptation of C.edulis to local envi-ronments has led to a differential selection of two complex clonal traits associated with the capacity for clonal integration.In patchy sand dunes,C.edulis has evolved ecotypes with ramets highly plastic in patterns of biomass allocation,which allows ramets to specialize in the acquisi-tion of the resource that is locally most abundant,i.e.,a spatial division of labour among ramets.However,in the harsher rocky coast habitats,local adaptation produced highly integrated ecotypes,where resource sharing is not combined with a specialization of resource acquisition.
基金This work was supported by funds from the Alien Species Network(Ref.ED431D 2017/20-Xunta de Galicia,Autonomous Government of Galicia).
文摘Aims One of the key traits associated with clonal growth in plants is the capacity for physiological integration,which allows resource sharing between connected ramets within a clonal system.Resource transport is expected to occur following a source–sink relationship:from ramets established in rich patches to ramets growing in poor patches.However,some experiments have shown that acropetal transport(from basal to apical modules)usually exceeds basipetal transport(from apical to basal ramets).In this study,we aimed to determine the resource transport directionality in physiologically integrated modules of the invader Carpobrotus edulis.Methods We conducted two manipulative experiments under common garden conditions that studied the effect of different nutrient levels located at different positions(basal,medial and apical)on connected and disconnected clonal systems of C.edulis.We compared the biomass partitioning patterns and final biomass of ramets to elucidate whether the effect of physiological integration is affected by the directionality of the resource transport.Important Findings Results indicate a prevalent acropetal transport of resources in C.edulis,with a developmentally programmed division of labor where basal ramets were specialized in obtaining soil-based resources and apical ramets specialized in aboveground growth.This biomass partitioning pattern was not affected by the nutrient conditions in which basal or apical ramets were growing,although the highest benefit was achieved by apical ramets growing under the most stressed conditions.This developmentally programmed division of labor is expected to increase the lateral growth of C.edulis,and therefore could have meaningful implications for the expansion of this invasive species.
基金We would like to acknowledge the financial support of the Italian Ministry of Education(MIUR),PRIN-COFIN.
文摘Aims Coastal areas,and in particular coastal dunes,are ecosystems strongly affected by the invasion of alien plants.However,few attempts have ever been made to quantify alien species incidence in different communities along the coastal zonation.This work aims to analyze the distribution of alien plants along the coastal zonation of sandy shores on the Tyrrhenian coast,addressing specifically differences among plant communities in abundance of alien plants.Methods The study was performed on recent dunes(Holocene)of the central western coast of Italy.We selected dune landscapes where invasion processes were particularly evident.Vegetation plots were randomly sampled and through cluster analysis,we identified six plant communities corresponding to the typical zonation described for the Tyrrhenian sandy coast of Central Italy.We evaluated and compared frequency and abundance of invasion in these different communities.Further,we investigated how propagule pressure(measured using as proxy human structures)contributed to the observed invasion patterns.Important Findings We found a relatively low total number of aliens but also a differential distribution pattern and strong abundance of some of the aliens in specific sectors of the vegetation zonation.The perennial community of transition dunes appears most affected by invasion processes,related almost exclusively to the frequent and widespread Carpobrotus aff.acinaciformis.This alien species reaches high cover values,apparently lowering cover of native species of transition dune plant communities.Higher levels of invasion in the transition dune can be partially explained because of greater propagule pressure in this section of the dune profile.Our findings thus have important conservation and management implications since transition dune communities with Crucianella maritima are rare and protected(sensu Habitat 92/43/EEC Directive)along the entire Italian coast.
基金P.S.-A.was funded by the Regional Council of Education,University and Professional Training(Conselleria de Educacion,Universidade e Formacion Profesional)from the Government of Galicia(Xunta de Galicia)through the annual Postdoctoral Plan'Axudas de apoio a etapa de formacion posdoutoral nas universidades doSistema universitario de Galicia'(grant ref.ED481B-2019-088)L.G.was funded by Xunta de Galicia,Spain(CITACA Strategic Partnership,grantref.:ED431E2018/07).
文摘Coastal dunes represent priority habitats for conservation due to the provision of valuable ecosystem services such as land protection,water supply or biodiversity conservation.Soil microbial communities are of crucial importance to maintain plant diversity due to harsh environmental conditions,water limitation and nutrient scarcity.Invasive alien plants represent a major threat to ecosystem conservation.Here,we explored different impacts of Carpobrotus edulis,a succulent plant invading coastal areas worldwide,on the function and structure of bacterial communities.Sand represents a challenging substrate due to low organic matter content and limited microbial activity.We optimized bacterial extraction for functional evaluation before assessing ecosystem impacts produced by C.edulis.We compared 12 extracting procedures combining different soil storage,sample amount and extracting solutions on the functional activity of sand communities through the community-level physiological profile.We further explored the function(using Biolog Ecoplates)and structure[using polymerase chain reaction–denaturing gradient gel electrophoresis(PCR-DGGE)]of bacterial communities from dunes invaded by C.edulis.Saline solution consistently increased bacterial cells detected by cytometry(P≤0.001).Principal component analysis suggested a limited temporal framework(0–24 h)in which community function can be explored without significant alterations in C substrate consumption.Changes under C.edulis invasion exhibited a different pattern of C substrate utilization comparing native and non-native zones(interspecific),but also between native zones(intraspecific),suggesting that functional impacts are site-dependent.Complementary,results obtained from PCR-DGGE indicated that the bacterial community structure of native dunes significantly differed from dunes invaded by C.edulis.
