Iron overload injury is considered to be a part of blood stasis syndrome of arthralgia in traditional Chinese medicine.Its primary therapies include clearing heat and detoxification,activating blood circulation,and re...Iron overload injury is considered to be a part of blood stasis syndrome of arthralgia in traditional Chinese medicine.Its primary therapies include clearing heat and detoxification,activating blood circulation,and removing blood stasis.Lonicera japonica flos(LJF)has long been known as an excellent antipyretic and antidote.Luteoloside(Lut)is one of the main components of LJF and exhibits antioxidant,anti-inflammatory,and cytoprotective properties.However,the protection of Lut against iron overload injury and its underlying mechanisms remain unclear.Therefore,HUVECs were exposed to 50μmol·L^(−1)iron dextran for 48 h to establish an iron overload damage model and the effects of Lut were assessed.Our results showed that 20μmol·L^(−1)Lut not only increased cell viability and weakened LDH activity,but also significantly up-regulated DDAHⅡexpression and activity,increased p-eNOS/eNOS ratio and NO content,and reduced ADMA content in HUVECs exposed to iron overload.Furthermore,Lut significantly attenuated intracellular/mitochondrial ROS generation,improved SOD,CAT,and GSH-Px activities,reduced MDA content,maintained MMP,inhibited mPTP opening,prevented cyt c from mitochondria released into cytoplasm,reduced cleaved-caspase3 expression,and ultimately decreased cell apoptosis induced by iron overload.The effects of Lut were similar to those of L-arginine(an ADMA competitive substrate),cyclosporin A(a mPTP blocker agent),and edaravone(a free radical scavenger)as positive controls.However,addition of pAD/DDAHⅡ-shRNA adenovirus reversed the above beneficial effects of Lut.In conclusion,Lut can protect HUVECs against iron overload injury via the ROS/ADMA/DDAHⅡ/eNOS/NO pathway.The mitochondria are the target organelles of Lut’s protective effects.展开更多
Introduction:Patients with CKD have elevated plasma levels of Asymmetrical Dimethyl Arginine (ADMA), impaired EDRF/NO responses in isolated resistance vessels, and a marked increase in the frequency of cardiovascular ...Introduction:Patients with CKD have elevated plasma levels of Asymmetrical Dimethyl Arginine (ADMA), impaired EDRF/NO responses in isolated resistance vessels, and a marked increase in the frequency of cardiovascular events that are predicated by plasma levels of ADMA. ADMA is considered as a risk factor for endothelial dysfunction, progression of chronic kidney disease and a marked increase in the frequency of cardiovascular events that are predicated by plasma levels of ADMA. Elevated ADMA in CKD have been related to a combination of a reduced renal ADMA excretion and a reduced catabolism of ADMA by dimethylarginine dimethylaminohydrolase (DDAH). The current study was undertaken to determine whether there is a correlation between ADMA and SNPs at -449 DDAH 2.Subjects and Methods :It was a cross sectional analytic study, 56 hemodialysis patients and 30 healthy individuals were enrolled. Based on its etiology, HD patients group was further divided in to hypertension (HT) subgroup and non-HT subgroup. Genotyping of the polymorphisms was performed using PCR-based SNP detection methods based on 5’-exonuclease activity assays for rs805305.Results :Heterozygotes were observed as the most abundant genotypes in both groups, followed by GG genotype in the HD patients (30%) and CC (27%) healthy individuals. Among the HT subgroup, the mean plasma levels of ADMA were sequentially higher from genotypes CC, G/C and GG (p = 0.037). Further multiple comparisons between groups using post hoc test showed results that genotype GG and CC were different at 0.05 level of significance. These findings were not found among non HT subgroup.Conclusion: Genetic variation in the DDAH 2 genes is significantly associated with serum ADMA levels in hypertensive HD patients. We observed that carriage of a G at position -449 in the promoter region of the DDAH 2 gene is associated with higher ADMA levels.展开更多
Choline acetyltransferase(ChAT)-positive neurons in neural stem cell(NSC)niches can evoke adult neurogenesis(AN)and restore impaired brain function after injury,such as acute ischemic stroke(AIS).However,the relevant ...Choline acetyltransferase(ChAT)-positive neurons in neural stem cell(NSC)niches can evoke adult neurogenesis(AN)and restore impaired brain function after injury,such as acute ischemic stroke(AIS).However,the relevant mechanism by which ChAT+neurons develop in NSC niches is poorly understood.Our RNA-seq analysis revealed that dimethylarginine dimethylaminohydrolase 1(DDAH1),a hydrolase for asymmetric NG,NG-dimethylarginine(ADMA),regulated genes responsible for the synthesis and transportation of acetylcholine(ACh)(Chat,Slc5a7 and Slc18a3)after stroke insult.The dual-luciferase reporter assay further suggested that DDAH1 controlled the activity of ChAT,possibly through hypoxia-inducible factor 1α(HIF-1α).KC7F2,an inhibitor of HIF-1α,abolished DDAH1-induced ChAT expression and suppressed neurogenesis.As expected,DDAH1 was clinically elevated in the blood of AIS patients and was positively correlated with AIS severity.By comparing the results among Ddah1 general knockout(KO)mice,transgenic(TG)mice and wild-type(WT)mice,we discovered that DDAH1 upregulated the proliferation and neural differentiation of NSCs in the subgranular zone(SGZ)under ischemic insult.As a result,DDAH1 may promote cognitive and motor function recovery against stroke impairment,while these neuroprotective effects are dramatically suppressed by NSC conditional knockout of Ddah1 in mice.展开更多
基金the National Natural Science Foundation of China(Nos.21467017,81660583,81673431,and 81803534)Jiangxi Applied Research and Cultivation Program(No.20181BBG78059).
文摘Iron overload injury is considered to be a part of blood stasis syndrome of arthralgia in traditional Chinese medicine.Its primary therapies include clearing heat and detoxification,activating blood circulation,and removing blood stasis.Lonicera japonica flos(LJF)has long been known as an excellent antipyretic and antidote.Luteoloside(Lut)is one of the main components of LJF and exhibits antioxidant,anti-inflammatory,and cytoprotective properties.However,the protection of Lut against iron overload injury and its underlying mechanisms remain unclear.Therefore,HUVECs were exposed to 50μmol·L^(−1)iron dextran for 48 h to establish an iron overload damage model and the effects of Lut were assessed.Our results showed that 20μmol·L^(−1)Lut not only increased cell viability and weakened LDH activity,but also significantly up-regulated DDAHⅡexpression and activity,increased p-eNOS/eNOS ratio and NO content,and reduced ADMA content in HUVECs exposed to iron overload.Furthermore,Lut significantly attenuated intracellular/mitochondrial ROS generation,improved SOD,CAT,and GSH-Px activities,reduced MDA content,maintained MMP,inhibited mPTP opening,prevented cyt c from mitochondria released into cytoplasm,reduced cleaved-caspase3 expression,and ultimately decreased cell apoptosis induced by iron overload.The effects of Lut were similar to those of L-arginine(an ADMA competitive substrate),cyclosporin A(a mPTP blocker agent),and edaravone(a free radical scavenger)as positive controls.However,addition of pAD/DDAHⅡ-shRNA adenovirus reversed the above beneficial effects of Lut.In conclusion,Lut can protect HUVECs against iron overload injury via the ROS/ADMA/DDAHⅡ/eNOS/NO pathway.The mitochondria are the target organelles of Lut’s protective effects.
文摘Introduction:Patients with CKD have elevated plasma levels of Asymmetrical Dimethyl Arginine (ADMA), impaired EDRF/NO responses in isolated resistance vessels, and a marked increase in the frequency of cardiovascular events that are predicated by plasma levels of ADMA. ADMA is considered as a risk factor for endothelial dysfunction, progression of chronic kidney disease and a marked increase in the frequency of cardiovascular events that are predicated by plasma levels of ADMA. Elevated ADMA in CKD have been related to a combination of a reduced renal ADMA excretion and a reduced catabolism of ADMA by dimethylarginine dimethylaminohydrolase (DDAH). The current study was undertaken to determine whether there is a correlation between ADMA and SNPs at -449 DDAH 2.Subjects and Methods :It was a cross sectional analytic study, 56 hemodialysis patients and 30 healthy individuals were enrolled. Based on its etiology, HD patients group was further divided in to hypertension (HT) subgroup and non-HT subgroup. Genotyping of the polymorphisms was performed using PCR-based SNP detection methods based on 5’-exonuclease activity assays for rs805305.Results :Heterozygotes were observed as the most abundant genotypes in both groups, followed by GG genotype in the HD patients (30%) and CC (27%) healthy individuals. Among the HT subgroup, the mean plasma levels of ADMA were sequentially higher from genotypes CC, G/C and GG (p = 0.037). Further multiple comparisons between groups using post hoc test showed results that genotype GG and CC were different at 0.05 level of significance. These findings were not found among non HT subgroup.Conclusion: Genetic variation in the DDAH 2 genes is significantly associated with serum ADMA levels in hypertensive HD patients. We observed that carriage of a G at position -449 in the promoter region of the DDAH 2 gene is associated with higher ADMA levels.
基金This work was supported by the National Natural Science Foundation of China(32171237,82070250,82171301,82370275,32071126)Beijing Natural Science Foundation(7222010)the Fundamental Research Funds for the Central Universities.Thanks for the support of the undergraduate research training programs of Capital Medical University(XSKY2023,XSKY2022,XSKY2021),China.We sincerely acknowledged that Professor Jianwei Jiao from the Institute of Zoology,Chinese Academy of Sciences,kindly provided the Nestin-Cre(C57BL/6.Cg-Tg(Nes-Cre)1Kln/J)mice.We sincerely appreciate for the technical service and support from Tissue Gnostics Asia Pacific Limited in the image caption and data analysis of immunohistochemical staining analysis.
文摘Choline acetyltransferase(ChAT)-positive neurons in neural stem cell(NSC)niches can evoke adult neurogenesis(AN)and restore impaired brain function after injury,such as acute ischemic stroke(AIS).However,the relevant mechanism by which ChAT+neurons develop in NSC niches is poorly understood.Our RNA-seq analysis revealed that dimethylarginine dimethylaminohydrolase 1(DDAH1),a hydrolase for asymmetric NG,NG-dimethylarginine(ADMA),regulated genes responsible for the synthesis and transportation of acetylcholine(ACh)(Chat,Slc5a7 and Slc18a3)after stroke insult.The dual-luciferase reporter assay further suggested that DDAH1 controlled the activity of ChAT,possibly through hypoxia-inducible factor 1α(HIF-1α).KC7F2,an inhibitor of HIF-1α,abolished DDAH1-induced ChAT expression and suppressed neurogenesis.As expected,DDAH1 was clinically elevated in the blood of AIS patients and was positively correlated with AIS severity.By comparing the results among Ddah1 general knockout(KO)mice,transgenic(TG)mice and wild-type(WT)mice,we discovered that DDAH1 upregulated the proliferation and neural differentiation of NSCs in the subgranular zone(SGZ)under ischemic insult.As a result,DDAH1 may promote cognitive and motor function recovery against stroke impairment,while these neuroprotective effects are dramatically suppressed by NSC conditional knockout of Ddah1 in mice.
