目的通过动物和体外培养的软骨细胞观察糖基化终末产物(advanced glycation end products,AGEs)对软骨细胞线粒体功能的损伤作用,并探讨相关机制。方法小鼠膝关节腔直接注射AGEs,番红O-固绿染色评估病理学改变;JC-1检测线粒体膜电位ΔΨ...目的通过动物和体外培养的软骨细胞观察糖基化终末产物(advanced glycation end products,AGEs)对软骨细胞线粒体功能的损伤作用,并探讨相关机制。方法小鼠膝关节腔直接注射AGEs,番红O-固绿染色评估病理学改变;JC-1检测线粒体膜电位ΔΨm;Western blot检测腺苷酸活化蛋白激酶(adenosine monophosphate-activated protein kinase,AMPK)、过氧化物酶体增殖物激活受体γ辅助活化因子α(peroxisome proliferator-activated receptorγcoactivator-1α,PGC-1α)、去乙酰化酶3(sirtuin3,SIRT3)及基质金属蛋白酶(matrix metalloproteinase,MMP)-3、-13的表达。结果膝关节注射AGEs 8周后,小鼠出现骨关节炎样病理改变;在体外培养的软骨细胞中,AGEs可以损伤线粒体功能,同时p-AMPK、SIRT3和PGC-1α的表达减少;给予AMPK选择性激动剂AICAR则可以拮抗AGEs的上述作用,而特异性敲除SIRT3或PGC-1α后,AICAR此拮抗作用减弱。结论AGEs可能通过下调AMPK-PGC-1α-SIRT3信号通路诱导软骨细胞线粒体功能损伤,进而促进OA病变。展开更多
目的探究大蒜素对动脉粥样硬化模型小鼠骨代谢的改善作用及其潜在作用机制。方法SPF级ApoE-/-雄性小鼠经高脂饲料喂养8周后,采用随机分组法进行分组,每组8只,包括模型组、大蒜素组及阿托伐他汀组,连续给药9周。另取C57BL/6N野生型小鼠8...目的探究大蒜素对动脉粥样硬化模型小鼠骨代谢的改善作用及其潜在作用机制。方法SPF级ApoE-/-雄性小鼠经高脂饲料喂养8周后,采用随机分组法进行分组,每组8只,包括模型组、大蒜素组及阿托伐他汀组,连续给药9周。另取C57BL/6N野生型小鼠8只,作为对照组,给予普通饲料常规喂养。利用生化法测定小鼠血脂变化,包括总胆固醇(total cholesterol,TC)、甘油三酯(triglyceride,TG)、高密度脂蛋白胆固醇(high density lipoprotein cholesterol,HDL-C)和低密度脂蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)水平。利用ELISA法测定血清骨吸收标志物,包括TRAP和CTX-1的变化。此外,利用Micro-CT检测小鼠骨微结构改变,并通过傅里叶变换红外光谱法检测骨材料特性,利用HE染色与TRAP染色观察骨组织病理学变化,利用Western blotting检测骨组织内骨吸收以及PPARγ/ERRα/PGC-1β通路相关蛋白的表达。结果大蒜素干预能显著降低动脉粥样硬化小鼠的血清TG、TC、HDL-C和LDL-C水平,同时抑制小鼠骨微结构的破坏,改善骨材料特性,以及抑制骨组织结构的病理损伤。此外,大蒜素能下调动脉粥样硬化小鼠血清中TRAP与CTX-1的水平,并降低其骨组织NFATc1、c-Fos、Cathepsin K蛋白的表达,抑制PPARγ、ERRα和PGC-1β蛋白的表达。结论大蒜素能通过抑制PPARγ/ERRα/PGC-1β通路,改善动脉粥样硬化小鼠的骨质量,进而防治骨质疏松的发生和发展。展开更多
Background This study investigated the molecular mechanisms by which redox status regulates protoporphyrin IX(PpIX)biosynthesis and eggshell coloration in brown-shelled laying hens.This study consisted of two experime...Background This study investigated the molecular mechanisms by which redox status regulates protoporphyrin IX(PpIX)biosynthesis and eggshell coloration in brown-shelled laying hens.This study consisted of two experiments involving 48 and 32 healthy 60-week-old Hy-Line Brown hens,respectively.The hens exhibited either dark(L*=51.99±2.08)or light(L*=64.12±3.02)brown eggshell colors.In Exp.1,light brown-shelled hens were fed a basal diet(Lb group),while dark brown-shelled hens received either a basal diet(Db group)or a basal diet with 10 mg/kg ammonium metavanadate(Dbv group)for 20 d.In Exp.2,light brown-shelled hens received either a basal diet(Lbc group)or a basal diet supplemented with 200 mg/kg resveratrol(Lbr group)for 12 weeks.Results Compared to the Db group,eggshell L*values increased,and PpIX concentrations in both eggshell and uterus decreased in Dbv and Lb groups.These groups also showed oxidative stress,as indicated by reduced hepatic T-SOD and CAT activities.Uterine redox status changes were further confirmed by increased T-AOC level(Dbv)and reduced CAT gene expression(Lb).These redox disturbances led to reduced expression of ND4 and COX1 mt DNA,decreased ATP production and CS activity,along with upregulation of IR,PI3K,HK,and PK gene expression,reflecting altered mitochondrial energy metabolism.Notably,the SIRT1/PGC-1αsignaling cascade and its downstream target ALAS1 were significantly downregulated at both mRNA and protein levels in Dbv and Lb groups.Compared to the Lbc group,the Lbr group exhibited higher antioxidant capacity by increasing hepatic CAT activity and uterine T-SOD and GSH-Px activities,and reducing MDA levels.Moreover,the Lbr group restored mitochondrial function and PpIX biosynthesis by upregulating ND4 and COX1 mt DNA,CS and SDHA gene expression,and SIRT1/PGC-1α/ALAS1 signaling,while downregulating LDH activity and the expression of IR and PI3K,thereby alleviating eggshell color fading.Conclusion Oxidative stress induces eggshell depigmentation by impairing mitochondrial function and downregulating the SIRT1/PGC-1α/ALAS1 pathway,leading to reduced PpIX biosynthesis.Specifically,vanadium-induced or endogenous oxidative stress disrupts mitochondrial energy metabolism and suppresses key components of this pathway,while resveratrol alleviates oxidative damage and restores mitochondrial function and ALAS1-driven PpIX synthesis through reactivation of the SIRT1/PGC-1αaxis.展开更多
文摘目的探究大蒜素对动脉粥样硬化模型小鼠骨代谢的改善作用及其潜在作用机制。方法SPF级ApoE-/-雄性小鼠经高脂饲料喂养8周后,采用随机分组法进行分组,每组8只,包括模型组、大蒜素组及阿托伐他汀组,连续给药9周。另取C57BL/6N野生型小鼠8只,作为对照组,给予普通饲料常规喂养。利用生化法测定小鼠血脂变化,包括总胆固醇(total cholesterol,TC)、甘油三酯(triglyceride,TG)、高密度脂蛋白胆固醇(high density lipoprotein cholesterol,HDL-C)和低密度脂蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)水平。利用ELISA法测定血清骨吸收标志物,包括TRAP和CTX-1的变化。此外,利用Micro-CT检测小鼠骨微结构改变,并通过傅里叶变换红外光谱法检测骨材料特性,利用HE染色与TRAP染色观察骨组织病理学变化,利用Western blotting检测骨组织内骨吸收以及PPARγ/ERRα/PGC-1β通路相关蛋白的表达。结果大蒜素干预能显著降低动脉粥样硬化小鼠的血清TG、TC、HDL-C和LDL-C水平,同时抑制小鼠骨微结构的破坏,改善骨材料特性,以及抑制骨组织结构的病理损伤。此外,大蒜素能下调动脉粥样硬化小鼠血清中TRAP与CTX-1的水平,并降低其骨组织NFATc1、c-Fos、Cathepsin K蛋白的表达,抑制PPARγ、ERRα和PGC-1β蛋白的表达。结论大蒜素能通过抑制PPARγ/ERRα/PGC-1β通路,改善动脉粥样硬化小鼠的骨质量,进而防治骨质疏松的发生和发展。
基金financially supported by the National Natural Science Foundation of China(32322078)the earmarked fund for the China Agriculture Research System(CARS-40)+1 种基金the China Postdoctoral Science Foundation(grant no.2024M763615)the Agricultural Science and Technology Innovation Program(ASTIP)of CAAS。
文摘Background This study investigated the molecular mechanisms by which redox status regulates protoporphyrin IX(PpIX)biosynthesis and eggshell coloration in brown-shelled laying hens.This study consisted of two experiments involving 48 and 32 healthy 60-week-old Hy-Line Brown hens,respectively.The hens exhibited either dark(L*=51.99±2.08)or light(L*=64.12±3.02)brown eggshell colors.In Exp.1,light brown-shelled hens were fed a basal diet(Lb group),while dark brown-shelled hens received either a basal diet(Db group)or a basal diet with 10 mg/kg ammonium metavanadate(Dbv group)for 20 d.In Exp.2,light brown-shelled hens received either a basal diet(Lbc group)or a basal diet supplemented with 200 mg/kg resveratrol(Lbr group)for 12 weeks.Results Compared to the Db group,eggshell L*values increased,and PpIX concentrations in both eggshell and uterus decreased in Dbv and Lb groups.These groups also showed oxidative stress,as indicated by reduced hepatic T-SOD and CAT activities.Uterine redox status changes were further confirmed by increased T-AOC level(Dbv)and reduced CAT gene expression(Lb).These redox disturbances led to reduced expression of ND4 and COX1 mt DNA,decreased ATP production and CS activity,along with upregulation of IR,PI3K,HK,and PK gene expression,reflecting altered mitochondrial energy metabolism.Notably,the SIRT1/PGC-1αsignaling cascade and its downstream target ALAS1 were significantly downregulated at both mRNA and protein levels in Dbv and Lb groups.Compared to the Lbc group,the Lbr group exhibited higher antioxidant capacity by increasing hepatic CAT activity and uterine T-SOD and GSH-Px activities,and reducing MDA levels.Moreover,the Lbr group restored mitochondrial function and PpIX biosynthesis by upregulating ND4 and COX1 mt DNA,CS and SDHA gene expression,and SIRT1/PGC-1α/ALAS1 signaling,while downregulating LDH activity and the expression of IR and PI3K,thereby alleviating eggshell color fading.Conclusion Oxidative stress induces eggshell depigmentation by impairing mitochondrial function and downregulating the SIRT1/PGC-1α/ALAS1 pathway,leading to reduced PpIX biosynthesis.Specifically,vanadium-induced or endogenous oxidative stress disrupts mitochondrial energy metabolism and suppresses key components of this pathway,while resveratrol alleviates oxidative damage and restores mitochondrial function and ALAS1-driven PpIX synthesis through reactivation of the SIRT1/PGC-1αaxis.
