Objective To investigate whether plasma big endothelin-1(ET-1) predicts ventricular arrythmias(VAs) and end-stage events in primary prevention implantable cardioverter-defibrillator(ICD) indication patigents. Methods ...Objective To investigate whether plasma big endothelin-1(ET-1) predicts ventricular arrythmias(VAs) and end-stage events in primary prevention implantable cardioverter-defibrillator(ICD) indication patigents. Methods In total, 207 patients fulfilling the inclusion criteria from Fuwai Hospital between January 2013 and December 2015 were retrospectively analyzed. The cohort was divided into three groups according to baseline plasma big ET-1 tertiles: tertile 1(< 0.38 pmol/L, n = 68), tertile 2(0.38–0.7 pmol/L, n = 69), and tertile 3(> 0.7 pmol/L, n = 70). The primary endpoints were VAs. The secondary endpoints were end-stage events comprising all-cause mortality and heart transplantation. Results During a mean follow-up period of 25.6 ± 13.9 months, 38(18.4%) VAs and 78(37.7%) end-stage events occurred. Big ET-1 was positively correlated with NYHA class(r = 0.165, P = 0.018), serum creatinine concentration(Scr;r = 0.147, P = 0.034), high-sensitivity C-reactive protein(hs-CRP;r = 0.217, P = 0.002), Lg NT-pro BNP(r = 0.463, P < 0.001), left ventricular end diastolic diameter(LVEDD;r = 0.234, P = 0.039) and negatively correlated with left ventricular ejection fraction(LVEF;r =-0.181, P = 0.032). Kaplan-Meier analysis showed that elevated big ET-1 was associated with increased risk of VAs and end-stage events(P < 0.05). In multivariate Cox regression models, big ET-1 was an independent risk factor for VAs(hazard ratio(HR) = 3.477, 95% confidence interval(CI): 1.352–8.940, P = 0.010, tertile 2 vs. tertile 1;HR = 4.112, 95% CI: 1.604–10.540, P = 0.003, tertile 3 vs. tertile 1) and end-stage events(HR = 2.804, 95% CI: 1.354–5.806, P = 0.005, tertile 2 vs. tertile 1;HR = 4.652, 95% CI: 2.288–9.459, P < 0.001, tertile 3 vs. tertile 1). Conclusions In primary prevention ICD indication patients, plasma big ET-1 levels can predict VAs and end-stage events and may facilitate ICD-implantation risk stratification.展开更多
Vascular etiology is the second most prevalent cause of cognitive impairment globally.Endothelin-1,which is produced and secreted by endothelial cells and astrocytes,is implicated in the pathogenesis of stroke.However...Vascular etiology is the second most prevalent cause of cognitive impairment globally.Endothelin-1,which is produced and secreted by endothelial cells and astrocytes,is implicated in the pathogenesis of stroke.However,the way in which changes in astrocytic endothelin-1 lead to poststroke cognitive deficits following transient middle cerebral artery occlusion is not well understood.Here,using mice in which astrocytic endothelin-1 was overexpressed,we found that the selective overexpression of endothelin-1 by astrocytic cells led to ischemic stroke-related dementia(1 hour of ischemia;7 days,28 days,or 3 months of reperfusion).We also revealed that astrocytic endothelin-1 overexpression contributed to the role of neural stem cell proliferation but impaired neurogenesis in the dentate gyrus of the hippocampus after middle cerebral artery occlusion.Comprehensive proteome profiles and western blot analysis confirmed that levels of glial fibrillary acidic protein and peroxiredoxin 6,which were differentially expressed in the brain,were significantly increased in mice with astrocytic endothelin-1 overexpression in comparison with wild-type mice 28 days after ischemic stroke.Moreover,the levels of the enriched differentially expressed proteins were closely related to lipid metabolism,as indicated by Kyoto Encyclopedia of Genes and Genomes pathway analysis.Liquid chromatography-mass spectrometry nontargeted metabolite profiling of brain tissues showed that astrocytic endothelin-1 overexpression altered lipid metabolism products such as glycerol phosphatidylcholine,sphingomyelin,and phosphatidic acid.Overall,this study demonstrates that astrocytic endothelin-1 overexpression can impair hippocampal neurogenesis and that it is correlated with lipid metabolism in poststroke cognitive dysfunction.展开更多
Lycium barbarum, a traditional Chinese anti-aging herb, has been shown to protect retinal ganglion cells （RGCs） in a rat chronic ocular hypertension （COH） model. Here, we investigated the expression of endothelin...Lycium barbarum, a traditional Chinese anti-aging herb, has been shown to protect retinal ganglion cells （RGCs） in a rat chronic ocular hypertension （COH） model. Here, we investigated the expression of endothelin-1 （ET-1）, a strong vasoconstrictor, and its receptors, ETA and ETB, in the COH model and assessed the effects of Lycium barbarum on the ET-1 axis. Elevated intraocular pressure （IOP） was induced in the right eye of SD rats using argon laser photocoagulation. （1） The expression of ET-1, ETA and ETB in normal and COH retinas was studied. （2） Some COH rats were fed daily with Lycium barbarum Polysaccharides （LBP） using 1 mg/kg or phosphate-buffered saline （PBS） for 3 weeks （started 1 week before photocoagulation）. The effects of LBP on the expression of ET-1 and its receptors, ETA and ETB, in COH retina were evaluated. A semi-quantitative analysis of staining intensity was used to evaluate the expression levels of ET-1, ETA and ETB in retinal vasculature. We found that （1） Under COH condition, the immunoreactivity of ET-1 was increased in retina associated with an increase of ETB receptor immunoreactivity and a decrease of ETA receptor immunoreactivity. （2） After feeding COH rats with LBP, the expression of ET-1 was decreased with an increase of ETA expression and a decrease of ETB expression in the retina, especially in RGCs. （3） By comparing the staining intensity in the vasculature of COH retina in LBP-fed group with PBS-fed group, there was a decrease in the expression of ET-1 and ETA and an increase in ETB. In summary, ET-1 expression was up-regulated in the retina in COH model. LBP could decrease the expression of ET-1 and modulate the expression of its receptors, ETA and ETB, under the condition of COH. The neuroprotective effect of LBP on RGCs might be related to its ability to regulate the ET-1-mediated biological effects on RGCs and retinal vasculature.展开更多
AIM： To examine the ability of FT-1 to affect the cell functions of PSCs and the underlying molecular mechanisms. METHODS： PSCs were isolated from the pancreas of male Wistar rats after perfusion with collagenase, a...AIM： To examine the ability of FT-1 to affect the cell functions of PSCs and the underlying molecular mechanisms. METHODS： PSCs were isolated from the pancreas of male Wistar rats after perfusion with collagenase, and cells between passages two and five were used. Expression of ET-1 and FT receptors was assessed by reverse transcription-PCR and immunostaining. Phosphorylation of myosin regulatory light chain （MLC）, extracellular-signal regulated kinase （FRK）, and Akt was examined by Western blotting. Contraction of PSCs was assessed on hydrated collagen lattices. Cell migration was examined using modified Boyden chambers. Ceil proliferation was assessed by measuring the incorporation of 5-bromo-2＇- deoxyuridine. RESULTS： Culture-activated PSCs expressed ETA and ETB receptors, and ET-1. ET-1 induced phosphorylation of NLC and FRK, but not Akt. ET-1 induced contraction and migration, but did not alter proliferation of PSCs. FT-1-induced contraction was inhibited by an ETA receptor antagonist BQ-123 and an ETB receptor antagonist BQ-788, whereas migration was inhibited by BQ-788 but not by BQ-123. A Rho kinase inhibitor Y-27632 abolished both contraction and migration. CONCLUSION： ET-1 induced contraction and migration of PSCs through El receptors and activation of Rho-Rho kinase. ETA and FTB receptors play different roles in the regulation of these cellular functions in response to ET-1.展开更多
To investigate the effects of L-tetrahydropalmatine (L-THP) on ener-gy metabolism, endothelin-1 (ET-1 ) and NO during acute cerebral ischemia-reperfusion of rats, 24 Wistar rats were randomly divided into four groups,...To investigate the effects of L-tetrahydropalmatine (L-THP) on ener-gy metabolism, endothelin-1 (ET-1 ) and NO during acute cerebral ischemia-reperfusion of rats, 24 Wistar rats were randomly divided into four groups, with 6rats in each group: sham-operation group, simple ischemia group, ischemia-reperfusion group and treatment group (L-THP group). Cerebral ATP, lactate,ET-1 and NO levels were measured in all groups. Our results showed that treat-ment with L-THP could increase cerebral ATP levels, but decrease cerebral lac-tate, ET-1 and NO concentrations during ischemia-reperfusion in the treatmentgroup. It is concluded that L-THP could improve cerebral energy metabolism and protect the injured brain tissue, the mechanism of which might be related to suppression of overproduction of ET-1 and NO.展开更多
AIM:To investigate endothelin-1 hypo-responsive associated with portal hypertension in order to improve patient treatment outcomes.METHODS:Wild type,e NOS-/-and i NOS-/-mice receivedpartial portal vein ligation surger...AIM:To investigate endothelin-1 hypo-responsive associated with portal hypertension in order to improve patient treatment outcomes.METHODS:Wild type,e NOS-/-and i NOS-/-mice receivedpartial portal vein ligation surgery to induce portal hypertension or sham surgery.Development of portal hypertension was determined by measuring the splenic pulp pressure,abdominal aortic flow and portal systemic shunting.To measure splenic pulp pressure,a microtip pressure transducer was inserted into the spleen pulp.Abdominal aortic flow was measured by placing an ultrasonic Doppler flow probe around the abdominal aorta between the diaphragm and celiac artery.Portal systemic shunting was calculated by injection of fluorescent microspheres in to the splenic vein and determining the percentage accumulation of spheres in liver and pulmonary beds.Endothelin-1 hypo-response was evaluated by measuring the change in abdominal aortic flow in response to endothelin-1 intravenous administration.In addition,thoracic aorta endothelin-1contraction was measured in 5 mm isolated thoracic aorta rings ex-vivo using an ADI small vessel myograph.RESULTS:In wild type and i NOS-/-mice splenic pulp pressure increased from 7.5±1.1 mm Hg and 7.2±1 mm Hg to 25.4±3.1 mm Hg and 22±4 mm Hg respectively.In e NOS-/-mice splenic pulp pressure was increased after 1 d(P=NS),after which it decreased and by 7 d was not significantly elevated when compared to 7 d sham operated controls(6.9±0.6 mm Hg and 7.3±0.8 mm Hg respectively,P=0.3).Abdominal aortic flow was increased by 80%and 73%in 7 d portal vein ligated wild type and i NOS when compared to shams,whereas there was no significant difference in 7 d portal vein ligated e NOS-/-mice when compared to shams.Endothelin-1 induced a rapid reduction in abdominal aortic blood flow in wild type,e NOS-/-and i NOS-/-sham mice(50%±8%,73%±9%and 47%±9%respectively).Following portal vein ligation endothelin-1 reduction in blood flow was significantly diminished in each mouse group.Abdominal aortic flow was reduced by 19%±9%,32%±10%and 9%±9%in wild type,e NOS-/-and i NOS-/-mice respectively.CONCLUSION:Aberrant endothelin-1 response in murine portal hypertension is NOS isoform independent.Moreover,portal hypertension in the portal vein ligation model is independent of ET-1 function.展开更多
Endothelin-1（ET-1）, a potent vasoconstrictor, is involved in retinal vascular dysregulation and oxidative stress in glaucomatous eyes. Taurine（TAU）, a naturally occurring free amino acid, is known for its neuropro...Endothelin-1（ET-1）, a potent vasoconstrictor, is involved in retinal vascular dysregulation and oxidative stress in glaucomatous eyes. Taurine（TAU）, a naturally occurring free amino acid, is known for its neuroprotective and antioxidant properties. Hence, we evaluated its neuroprotective properties against ET-1 induced retinal and optic nerve damage. ET-1 was administered intravitreally to Sprague-Dawley rats and TAU was injected as pre-, co-or post-treatment. Animals were euthanized seven days post TAU injection. Retinae and optic nerve were examined for morphology, and were also processed for caspase-3 immunostaining. Retinal redox status was estimated by measuring retinal superoxide dismutase, catalase, glutathione, and malondialdehyde levels using enzyme-linked immuosorbent assay. Histopathological examination showed significantly improved retinal and optic nerve morphology in TAU-treated groups. Morphometric examination showed that TAU pre-treatment provided marked protection against ET-1 induced damage to retina and optic nerve. In accordance with the morphological observations, immunostaining for caspase showed a significantly lesser number of apoptotic retinal cells in the TAU pre-treatment group. The retinal oxidative stress was reduced in all TAU-treated groups, and particularly in the pre-treatment group. The findings suggest that treatment with TAU, particularly pre-treatment, prevents apoptosis of retinal cells induced by ET-1 and hence prevents the changes in the morphology of retina and optic nerve. The protective effect of TAU against ET-1 induced retinal and optic nerve damage is associated with reduced retinal oxidative stress.展开更多
Functional and structural alterations in brain connectivity associated with brain ischemia have been extensively studied. However, the mechanism whereby local ischemia in deep brain region affect brain functions is st...Functional and structural alterations in brain connectivity associated with brain ischemia have been extensively studied. However, the mechanism whereby local ischemia in deep brain region affect brain functions is still unknown. Here, we first established a mini-stroke model by infusion of endothelin-1 （ET-1） into the dorsal hippo- campus or the lateral amygdala, and then investigated how these mini-infarcts affected brain functions associated with these regions. We found that rats with ET-1 infusion showed deficit in recall of contextual fear memory, but not in learning process and recall of tone fear memory. In novel object task, ET-1 in the hippocampus also elimi- nated object identity memory. ET-1 in the lateral amygdale affected acquisition of fear conditioning and disrupted retention of tone-conditioned fear, but did not impair retention of contextual fear. These findings suggest that ET-1- induced mini-infarct in deep brain area leads to functional deficits in learning and memory associated with these regions.展开更多
基金supported by Natural Science Foundation of China(81470466)。
文摘Objective To investigate whether plasma big endothelin-1(ET-1) predicts ventricular arrythmias(VAs) and end-stage events in primary prevention implantable cardioverter-defibrillator(ICD) indication patigents. Methods In total, 207 patients fulfilling the inclusion criteria from Fuwai Hospital between January 2013 and December 2015 were retrospectively analyzed. The cohort was divided into three groups according to baseline plasma big ET-1 tertiles: tertile 1(< 0.38 pmol/L, n = 68), tertile 2(0.38–0.7 pmol/L, n = 69), and tertile 3(> 0.7 pmol/L, n = 70). The primary endpoints were VAs. The secondary endpoints were end-stage events comprising all-cause mortality and heart transplantation. Results During a mean follow-up period of 25.6 ± 13.9 months, 38(18.4%) VAs and 78(37.7%) end-stage events occurred. Big ET-1 was positively correlated with NYHA class(r = 0.165, P = 0.018), serum creatinine concentration(Scr;r = 0.147, P = 0.034), high-sensitivity C-reactive protein(hs-CRP;r = 0.217, P = 0.002), Lg NT-pro BNP(r = 0.463, P < 0.001), left ventricular end diastolic diameter(LVEDD;r = 0.234, P = 0.039) and negatively correlated with left ventricular ejection fraction(LVEF;r =-0.181, P = 0.032). Kaplan-Meier analysis showed that elevated big ET-1 was associated with increased risk of VAs and end-stage events(P < 0.05). In multivariate Cox regression models, big ET-1 was an independent risk factor for VAs(hazard ratio(HR) = 3.477, 95% confidence interval(CI): 1.352–8.940, P = 0.010, tertile 2 vs. tertile 1;HR = 4.112, 95% CI: 1.604–10.540, P = 0.003, tertile 3 vs. tertile 1) and end-stage events(HR = 2.804, 95% CI: 1.354–5.806, P = 0.005, tertile 2 vs. tertile 1;HR = 4.652, 95% CI: 2.288–9.459, P < 0.001, tertile 3 vs. tertile 1). Conclusions In primary prevention ICD indication patients, plasma big ET-1 levels can predict VAs and end-stage events and may facilitate ICD-implantation risk stratification.
基金financially supported by the National Natural Science Foundation of China,No.81303115,81774042 (both to XC)the Pearl River S&T Nova Program of Guangzhou,No.201806010025 (to XC)+3 种基金the Specialty Program of Guangdong Province Hospital of Chinese Medicine of China,No.YN2018ZD07 (to XC)the Natural Science Foundatior of Guangdong Province of China,No.2023A1515012174 (to JL)the Science and Technology Program of Guangzhou of China,No.20210201 0268 (to XC),20210201 0339 (to JS)Guangdong Provincial Key Laboratory of Research on Emergency in TCM,Nos.2018-75,2019-140 (to JS)
文摘Vascular etiology is the second most prevalent cause of cognitive impairment globally.Endothelin-1,which is produced and secreted by endothelial cells and astrocytes,is implicated in the pathogenesis of stroke.However,the way in which changes in astrocytic endothelin-1 lead to poststroke cognitive deficits following transient middle cerebral artery occlusion is not well understood.Here,using mice in which astrocytic endothelin-1 was overexpressed,we found that the selective overexpression of endothelin-1 by astrocytic cells led to ischemic stroke-related dementia(1 hour of ischemia;7 days,28 days,or 3 months of reperfusion).We also revealed that astrocytic endothelin-1 overexpression contributed to the role of neural stem cell proliferation but impaired neurogenesis in the dentate gyrus of the hippocampus after middle cerebral artery occlusion.Comprehensive proteome profiles and western blot analysis confirmed that levels of glial fibrillary acidic protein and peroxiredoxin 6,which were differentially expressed in the brain,were significantly increased in mice with astrocytic endothelin-1 overexpression in comparison with wild-type mice 28 days after ischemic stroke.Moreover,the levels of the enriched differentially expressed proteins were closely related to lipid metabolism,as indicated by Kyoto Encyclopedia of Genes and Genomes pathway analysis.Liquid chromatography-mass spectrometry nontargeted metabolite profiling of brain tissues showed that astrocytic endothelin-1 overexpression altered lipid metabolism products such as glycerol phosphatidylcholine,sphingomyelin,and phosphatidic acid.Overall,this study demonstrates that astrocytic endothelin-1 overexpression can impair hippocampal neurogenesis and that it is correlated with lipid metabolism in poststroke cognitive dysfunction.
基金supported by the Azalea (1972) Education fund to KFSo and RCCCFundamental Research Fund for The Centre Universities,No.21609101
文摘Lycium barbarum, a traditional Chinese anti-aging herb, has been shown to protect retinal ganglion cells （RGCs） in a rat chronic ocular hypertension （COH） model. Here, we investigated the expression of endothelin-1 （ET-1）, a strong vasoconstrictor, and its receptors, ETA and ETB, in the COH model and assessed the effects of Lycium barbarum on the ET-1 axis. Elevated intraocular pressure （IOP） was induced in the right eye of SD rats using argon laser photocoagulation. （1） The expression of ET-1, ETA and ETB in normal and COH retinas was studied. （2） Some COH rats were fed daily with Lycium barbarum Polysaccharides （LBP） using 1 mg/kg or phosphate-buffered saline （PBS） for 3 weeks （started 1 week before photocoagulation）. The effects of LBP on the expression of ET-1 and its receptors, ETA and ETB, in COH retina were evaluated. A semi-quantitative analysis of staining intensity was used to evaluate the expression levels of ET-1, ETA and ETB in retinal vasculature. We found that （1） Under COH condition, the immunoreactivity of ET-1 was increased in retina associated with an increase of ETB receptor immunoreactivity and a decrease of ETA receptor immunoreactivity. （2） After feeding COH rats with LBP, the expression of ET-1 was decreased with an increase of ETA expression and a decrease of ETB expression in the retina, especially in RGCs. （3） By comparing the staining intensity in the vasculature of COH retina in LBP-fed group with PBS-fed group, there was a decrease in the expression of ET-1 and ETA and an increase in ETB. In summary, ET-1 expression was up-regulated in the retina in COH model. LBP could decrease the expression of ET-1 and modulate the expression of its receptors, ETA and ETB, under the condition of COH. The neuroprotective effect of LBP on RGCs might be related to its ability to regulate the ET-1-mediated biological effects on RGCs and retinal vasculature.
基金Supported by Grant-in-Aid for Encouragement of Young Scientists from Japan Society for the Promotion of Science, No. 16590572 (to AM.)by Pancreas Research Foundation of Japan, No. 01-01 (to AM.)by the Kanae Foundation for Life and Socio-Medical Science(to AM)by the Uehara Memorial Foundation (to AM)
文摘AIM： To examine the ability of FT-1 to affect the cell functions of PSCs and the underlying molecular mechanisms. METHODS： PSCs were isolated from the pancreas of male Wistar rats after perfusion with collagenase, and cells between passages two and five were used. Expression of ET-1 and FT receptors was assessed by reverse transcription-PCR and immunostaining. Phosphorylation of myosin regulatory light chain （MLC）, extracellular-signal regulated kinase （FRK）, and Akt was examined by Western blotting. Contraction of PSCs was assessed on hydrated collagen lattices. Cell migration was examined using modified Boyden chambers. Ceil proliferation was assessed by measuring the incorporation of 5-bromo-2＇- deoxyuridine. RESULTS： Culture-activated PSCs expressed ETA and ETB receptors, and ET-1. ET-1 induced phosphorylation of NLC and FRK, but not Akt. ET-1 induced contraction and migration, but did not alter proliferation of PSCs. FT-1-induced contraction was inhibited by an ETA receptor antagonist BQ-123 and an ETB receptor antagonist BQ-788, whereas migration was inhibited by BQ-788 but not by BQ-123. A Rho kinase inhibitor Y-27632 abolished both contraction and migration. CONCLUSION： ET-1 induced contraction and migration of PSCs through El receptors and activation of Rho-Rho kinase. ETA and FTB receptors play different roles in the regulation of these cellular functions in response to ET-1.
文摘To investigate the effects of L-tetrahydropalmatine (L-THP) on ener-gy metabolism, endothelin-1 (ET-1 ) and NO during acute cerebral ischemia-reperfusion of rats, 24 Wistar rats were randomly divided into four groups, with 6rats in each group: sham-operation group, simple ischemia group, ischemia-reperfusion group and treatment group (L-THP group). Cerebral ATP, lactate,ET-1 and NO levels were measured in all groups. Our results showed that treat-ment with L-THP could increase cerebral ATP levels, but decrease cerebral lac-tate, ET-1 and NO concentrations during ischemia-reperfusion in the treatmentgroup. It is concluded that L-THP could improve cerebral energy metabolism and protect the injured brain tissue, the mechanism of which might be related to suppression of overproduction of ET-1 and NO.
基金Supported by Indiana University department of surgery and Lilly INGEN research fund provided support for the Research performed in this manuscript
文摘AIM:To investigate endothelin-1 hypo-responsive associated with portal hypertension in order to improve patient treatment outcomes.METHODS:Wild type,e NOS-/-and i NOS-/-mice receivedpartial portal vein ligation surgery to induce portal hypertension or sham surgery.Development of portal hypertension was determined by measuring the splenic pulp pressure,abdominal aortic flow and portal systemic shunting.To measure splenic pulp pressure,a microtip pressure transducer was inserted into the spleen pulp.Abdominal aortic flow was measured by placing an ultrasonic Doppler flow probe around the abdominal aorta between the diaphragm and celiac artery.Portal systemic shunting was calculated by injection of fluorescent microspheres in to the splenic vein and determining the percentage accumulation of spheres in liver and pulmonary beds.Endothelin-1 hypo-response was evaluated by measuring the change in abdominal aortic flow in response to endothelin-1 intravenous administration.In addition,thoracic aorta endothelin-1contraction was measured in 5 mm isolated thoracic aorta rings ex-vivo using an ADI small vessel myograph.RESULTS:In wild type and i NOS-/-mice splenic pulp pressure increased from 7.5±1.1 mm Hg and 7.2±1 mm Hg to 25.4±3.1 mm Hg and 22±4 mm Hg respectively.In e NOS-/-mice splenic pulp pressure was increased after 1 d(P=NS),after which it decreased and by 7 d was not significantly elevated when compared to 7 d sham operated controls(6.9±0.6 mm Hg and 7.3±0.8 mm Hg respectively,P=0.3).Abdominal aortic flow was increased by 80%and 73%in 7 d portal vein ligated wild type and i NOS when compared to shams,whereas there was no significant difference in 7 d portal vein ligated e NOS-/-mice when compared to shams.Endothelin-1 induced a rapid reduction in abdominal aortic blood flow in wild type,e NOS-/-and i NOS-/-sham mice(50%±8%,73%±9%and 47%±9%respectively).Following portal vein ligation endothelin-1 reduction in blood flow was significantly diminished in each mouse group.Abdominal aortic flow was reduced by 19%±9%,32%±10%and 9%±9%in wild type,e NOS-/-and i NOS-/-mice respectively.CONCLUSION:Aberrant endothelin-1 response in murine portal hypertension is NOS isoform independent.Moreover,portal hypertension in the portal vein ligation model is independent of ET-1 function.
基金the financial support by Universiti Teknologi MARA under grant No.600-IRMI/DANA5/3/BESTARI(006/2017)
文摘Endothelin-1（ET-1）, a potent vasoconstrictor, is involved in retinal vascular dysregulation and oxidative stress in glaucomatous eyes. Taurine（TAU）, a naturally occurring free amino acid, is known for its neuroprotective and antioxidant properties. Hence, we evaluated its neuroprotective properties against ET-1 induced retinal and optic nerve damage. ET-1 was administered intravitreally to Sprague-Dawley rats and TAU was injected as pre-, co-or post-treatment. Animals were euthanized seven days post TAU injection. Retinae and optic nerve were examined for morphology, and were also processed for caspase-3 immunostaining. Retinal redox status was estimated by measuring retinal superoxide dismutase, catalase, glutathione, and malondialdehyde levels using enzyme-linked immuosorbent assay. Histopathological examination showed significantly improved retinal and optic nerve morphology in TAU-treated groups. Morphometric examination showed that TAU pre-treatment provided marked protection against ET-1 induced damage to retina and optic nerve. In accordance with the morphological observations, immunostaining for caspase showed a significantly lesser number of apoptotic retinal cells in the TAU pre-treatment group. The retinal oxidative stress was reduced in all TAU-treated groups, and particularly in the pre-treatment group. The findings suggest that treatment with TAU, particularly pre-treatment, prevents apoptosis of retinal cells induced by ET-1 and hence prevents the changes in the morphology of retina and optic nerve. The protective effect of TAU against ET-1 induced retinal and optic nerve damage is associated with reduced retinal oxidative stress.
基金supported by Major State Basic Research Program of China(Grant No.2013CB733801)
文摘Functional and structural alterations in brain connectivity associated with brain ischemia have been extensively studied. However, the mechanism whereby local ischemia in deep brain region affect brain functions is still unknown. Here, we first established a mini-stroke model by infusion of endothelin-1 （ET-1） into the dorsal hippo- campus or the lateral amygdala, and then investigated how these mini-infarcts affected brain functions associated with these regions. We found that rats with ET-1 infusion showed deficit in recall of contextual fear memory, but not in learning process and recall of tone fear memory. In novel object task, ET-1 in the hippocampus also elimi- nated object identity memory. ET-1 in the lateral amygdale affected acquisition of fear conditioning and disrupted retention of tone-conditioned fear, but did not impair retention of contextual fear. These findings suggest that ET-1- induced mini-infarct in deep brain area leads to functional deficits in learning and memory associated with these regions.
