It is of great significance to study the effects of desert plants on soil enzyme activities and soil organic carbon(SOC)for maintaining the stability of the desert ecosystem.In this study,we studied the responses of s...It is of great significance to study the effects of desert plants on soil enzyme activities and soil organic carbon(SOC)for maintaining the stability of the desert ecosystem.In this study,we studied the responses of soil enzyme activities and SOC fractions(particulate organic carbon(POC)and mineral-associated organic carbon(MAOC))to five typical desert plant communities(Convolvulus tragacanthoides,Ephedra rhytidosperma,Stipa breviflora,Stipa tianschanica var.gobica,and Salsola laricifolia communities)in the proluvial fan in the eastern foothills of the Helan Mountain in Ningxia Hui Autonomous Region,China.We recorded the plant community information mainly including the plant coverage and herb and shrub species,and obtained the aboveground biomass and plant species diversity through sample surveys in late July 2023.Soil samples were also collected at depths of 0–10 cm(topsoil)and 10–20 cm(subsoil)to determine the soil physicochemical properties and enzyme activities.The results showed that the plant coverage and aboveground biomass of S.laricifolia community were significantly higher than those of C.tragacanthoides,S.breviflora,and S.tianschanica var.gobica communities(P<0.05).Soil enzyme activities varied among different plant communities.In the topsoil,the enzyme activities of alkaline phosphatase(ALP)andβ-1,4-glucosidas(βG)were significantly higher in E.rhytidosperma and S.tianschanica var.gobica communities than in other plant communities(P<0.05).The topsoil had higher POC and MAOC contents than the subsoil.Specifically,the content of POC in the topsoil was 18.17%–42.73%higher than that in the subsoil.The structural equation model(SEM)indicated that plant species diversity,soil pH,and soil water content(SWC)were the main factors influencing POC and MAOC.The soil pH inhibited the formation of POC and promoted the formation of MAOC.Conversely,SWC stimulated POC production and hindered MAOC formation.Our study aimed to gain insight into the effects of desert plant communities on soil enzyme activities and SOC fractions,as well as the drivers of SOC fractions in the proluvial fan in the eastern foothills of the Helan Mountain and other desert ecosystems.展开更多
目的基于CYP2J3/EETs介导脂肪酸代谢探讨化瘀祛痰方防治血脂异常的机制。方法32只SPF级SD大鼠分为空白对照组、模型组、化瘀祛痰方组、辛伐他汀组,每组8只。除空白对照组外,其他各组给予高脂饲料喂饲,建立高脂血症模型。于第13周开始,...目的基于CYP2J3/EETs介导脂肪酸代谢探讨化瘀祛痰方防治血脂异常的机制。方法32只SPF级SD大鼠分为空白对照组、模型组、化瘀祛痰方组、辛伐他汀组,每组8只。除空白对照组外,其他各组给予高脂饲料喂饲,建立高脂血症模型。于第13周开始,化瘀祛痰方组给予化瘀祛痰方灌胃,辛伐他汀组给予辛伐他汀灌胃,空白对照组、模型组给予相应体积的生理盐水灌胃,每日1次,灌胃4周。采用全自动生化分析仪检测各组大鼠血清中总胆固醇(Total cholesterol,TC)、甘油三酯(Triglyceride,TG)、低密度脂蛋白胆固醇(Low density lipoprotein cholesterol,LDL-C)及高密度脂蛋白胆固醇(High density lipoprotein cholesterol,HDL-C)水平;HE染色观察肝脏组织病理变化;Elisa检测各组大鼠肝脏14,15-环氧二十碳三烯酸(14,15-epoxyeicosatrienoic acid,14,15-EET)水平;Real time RT-PCR检测肝脏组织细胞色素P450表氧化酶2J3(Cytochrome P450 oxidase 2J3,CYP2J3)、肉毒碱棕榈酰转移酶1(Carnitine palmitoyltransferase-1,CPT-1)mRNA水平;Western blot法检测肝脏组织CYP2J3、腺苷酸活化蛋白激酶(AMP-actived protein kinase,AMPK)、磷酸化腺苷酸活化蛋白激酶(p-AMPK)、乙酰辅酶A羧化酶(Acetyl CoA Carboxylase,ACC)、磷酸化乙酰辅酶A羧化酶(p-ACC)、CPT-1蛋白水平。结果与空白对照组比较,模型组大鼠血清TC、TG和LDL-C水平显著升高(P<0.01),HDL-C水平显著降低(P<0.05);肝脏脂质沉积显著,可见大量脂滴;肝脏组织内14,15-EET含量显著降低(P<0.01);肝脏CYP2J3、CPT-1 mRNA和蛋白表达水平显著降低(P<0.01),p-AMPK/AMPK、p-ACC/ACC显著降低(P<0.01)。与模型组比较,经化瘀祛痰方及辛伐他汀干预后,大鼠血清TC、TG和LDL-C水平显著降低(P<0.05或P<0.01),HDL-C水平显著升高(P<0.05);肝脏脂质沉积情况明显改善,脂滴数明显减少;肝脏组织内14,15-EET水平显著升高(P<0.01);肝脏CYP2J3、CPT-1 mRNA和蛋白表达水平显著升高(P<0.05或P<0.01),p-AMPK/AMPK、p-ACC/ACC显著升高(P<0.05或P<0.01)。结论化瘀祛痰方可有效改善高脂血症大鼠血脂异常,减轻肝脏脂质沉积情况,其机制可能与CYP2J3/EETs介导脂肪酸代谢密切相关。展开更多
基金the Key Project of the Natural Science Foundation of Ningxia Hui Autonomous Region,China(2022AAC02020)the Major Strategic Research Project of the Chinese Academy of Engineering and Local Cooperation(2021NXZD8)the Key Research and Development Plan Project of Ningxia Hui Autonomous Region,China(2022004129003).We are grateful to the editors and anonymous reviewers for their insightful comments and suggestions in improving this manuscript.
文摘It is of great significance to study the effects of desert plants on soil enzyme activities and soil organic carbon(SOC)for maintaining the stability of the desert ecosystem.In this study,we studied the responses of soil enzyme activities and SOC fractions(particulate organic carbon(POC)and mineral-associated organic carbon(MAOC))to five typical desert plant communities(Convolvulus tragacanthoides,Ephedra rhytidosperma,Stipa breviflora,Stipa tianschanica var.gobica,and Salsola laricifolia communities)in the proluvial fan in the eastern foothills of the Helan Mountain in Ningxia Hui Autonomous Region,China.We recorded the plant community information mainly including the plant coverage and herb and shrub species,and obtained the aboveground biomass and plant species diversity through sample surveys in late July 2023.Soil samples were also collected at depths of 0–10 cm(topsoil)and 10–20 cm(subsoil)to determine the soil physicochemical properties and enzyme activities.The results showed that the plant coverage and aboveground biomass of S.laricifolia community were significantly higher than those of C.tragacanthoides,S.breviflora,and S.tianschanica var.gobica communities(P<0.05).Soil enzyme activities varied among different plant communities.In the topsoil,the enzyme activities of alkaline phosphatase(ALP)andβ-1,4-glucosidas(βG)were significantly higher in E.rhytidosperma and S.tianschanica var.gobica communities than in other plant communities(P<0.05).The topsoil had higher POC and MAOC contents than the subsoil.Specifically,the content of POC in the topsoil was 18.17%–42.73%higher than that in the subsoil.The structural equation model(SEM)indicated that plant species diversity,soil pH,and soil water content(SWC)were the main factors influencing POC and MAOC.The soil pH inhibited the formation of POC and promoted the formation of MAOC.Conversely,SWC stimulated POC production and hindered MAOC formation.Our study aimed to gain insight into the effects of desert plant communities on soil enzyme activities and SOC fractions,as well as the drivers of SOC fractions in the proluvial fan in the eastern foothills of the Helan Mountain and other desert ecosystems.
文摘目的基于CYP2J3/EETs介导脂肪酸代谢探讨化瘀祛痰方防治血脂异常的机制。方法32只SPF级SD大鼠分为空白对照组、模型组、化瘀祛痰方组、辛伐他汀组,每组8只。除空白对照组外,其他各组给予高脂饲料喂饲,建立高脂血症模型。于第13周开始,化瘀祛痰方组给予化瘀祛痰方灌胃,辛伐他汀组给予辛伐他汀灌胃,空白对照组、模型组给予相应体积的生理盐水灌胃,每日1次,灌胃4周。采用全自动生化分析仪检测各组大鼠血清中总胆固醇(Total cholesterol,TC)、甘油三酯(Triglyceride,TG)、低密度脂蛋白胆固醇(Low density lipoprotein cholesterol,LDL-C)及高密度脂蛋白胆固醇(High density lipoprotein cholesterol,HDL-C)水平;HE染色观察肝脏组织病理变化;Elisa检测各组大鼠肝脏14,15-环氧二十碳三烯酸(14,15-epoxyeicosatrienoic acid,14,15-EET)水平;Real time RT-PCR检测肝脏组织细胞色素P450表氧化酶2J3(Cytochrome P450 oxidase 2J3,CYP2J3)、肉毒碱棕榈酰转移酶1(Carnitine palmitoyltransferase-1,CPT-1)mRNA水平;Western blot法检测肝脏组织CYP2J3、腺苷酸活化蛋白激酶(AMP-actived protein kinase,AMPK)、磷酸化腺苷酸活化蛋白激酶(p-AMPK)、乙酰辅酶A羧化酶(Acetyl CoA Carboxylase,ACC)、磷酸化乙酰辅酶A羧化酶(p-ACC)、CPT-1蛋白水平。结果与空白对照组比较,模型组大鼠血清TC、TG和LDL-C水平显著升高(P<0.01),HDL-C水平显著降低(P<0.05);肝脏脂质沉积显著,可见大量脂滴;肝脏组织内14,15-EET含量显著降低(P<0.01);肝脏CYP2J3、CPT-1 mRNA和蛋白表达水平显著降低(P<0.01),p-AMPK/AMPK、p-ACC/ACC显著降低(P<0.01)。与模型组比较,经化瘀祛痰方及辛伐他汀干预后,大鼠血清TC、TG和LDL-C水平显著降低(P<0.05或P<0.01),HDL-C水平显著升高(P<0.05);肝脏脂质沉积情况明显改善,脂滴数明显减少;肝脏组织内14,15-EET水平显著升高(P<0.01);肝脏CYP2J3、CPT-1 mRNA和蛋白表达水平显著升高(P<0.05或P<0.01),p-AMPK/AMPK、p-ACC/ACC显著升高(P<0.05或P<0.01)。结论化瘀祛痰方可有效改善高脂血症大鼠血脂异常,减轻肝脏脂质沉积情况,其机制可能与CYP2J3/EETs介导脂肪酸代谢密切相关。