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
Objective To explore the mechanisms involved in the ligustrazine alleviation of the pulmonary artery hypertension(PAH) in patients of chronic obstructive pulmonary disease(COPD) associated with chronic cor pulmonale(C...Objective To explore the mechanisms involved in the ligustrazine alleviation of the pulmonary artery hypertension(PAH) in patients of chronic obstructive pulmonary disease(COPD) associated with chronic cor pulmonale(CCP) during exacerbation.Methods Seventy patients of COPD and CCP with acute exacerbation were randomly and equally divided into control group and treatment group.The control group received standard treatment with antibiotics,antiasthmatic and expectorant medications,and oxygenation;and the ligustrazine treatment group received ligustrazine treatment(80 mg/d;i.v.;for 2 weeks) in addition to the standard treatment.Before and at the end of 2 week treatment,the clinic responses of the two regimens were evaluated,plasma levels of endothelin-1(ET-1) and nitric oxide(NO) were determined;arterial oxygen partial pressure(PaO_2),mean pulmonary arterial pressure(mPAP),outflow tract of right ventricle(RVOT),and internal diameter of right ventricle(RV) were measured.Results Good clinic benefits were achieved in both the standard and ligustrazine regimens,plasma level of ET-1,values of mPAP,RV and RVOT decreased significantly,plasma level of NO and PaO_2 values decreased(all P<0.01 vs pretreatment to all parameters).Compared with the control group,ligustrazine greatly enhanced the clinic efficacy from 77.1%to 97.1%(P<0.05),and also resulted in more significant changes of all these parameters(P<0.01 vs control group for all parameters).For both groups,the levels of plasma ET-1 were positively correlated with values of mPAP,RVOT,and RV(r = 0.710,0.853,and 0.766,respectively,all P = 0.000),and negatively correlated with plasma NO and PaO_2(r =- 0.823,and- 0.752,respectively,all P = 0.000).Conclusion Ligustrazine is effective in treating pulmonary artery hypertension during acute exacerbation of COPD and CCP in patients from the plateau area.The observed changes in the plasma levels of NO and ET-1 in response to ligustrazine treatment suggest that ligustrazine may act through the selective effect on pulmonary blood vessels to enhance the synthesis and release of NO and suppress those of ET-1 from lung vascular endothelial cells,thus reducing pulmonary artery pressure and decreasing pulmonary arterial hypertension.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
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
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
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 the Key scientific and technological project in Qinghai Province,China (2006-N-143)
文摘Objective To explore the mechanisms involved in the ligustrazine alleviation of the pulmonary artery hypertension(PAH) in patients of chronic obstructive pulmonary disease(COPD) associated with chronic cor pulmonale(CCP) during exacerbation.Methods Seventy patients of COPD and CCP with acute exacerbation were randomly and equally divided into control group and treatment group.The control group received standard treatment with antibiotics,antiasthmatic and expectorant medications,and oxygenation;and the ligustrazine treatment group received ligustrazine treatment(80 mg/d;i.v.;for 2 weeks) in addition to the standard treatment.Before and at the end of 2 week treatment,the clinic responses of the two regimens were evaluated,plasma levels of endothelin-1(ET-1) and nitric oxide(NO) were determined;arterial oxygen partial pressure(PaO_2),mean pulmonary arterial pressure(mPAP),outflow tract of right ventricle(RVOT),and internal diameter of right ventricle(RV) were measured.Results Good clinic benefits were achieved in both the standard and ligustrazine regimens,plasma level of ET-1,values of mPAP,RV and RVOT decreased significantly,plasma level of NO and PaO_2 values decreased(all P<0.01 vs pretreatment to all parameters).Compared with the control group,ligustrazine greatly enhanced the clinic efficacy from 77.1%to 97.1%(P<0.05),and also resulted in more significant changes of all these parameters(P<0.01 vs control group for all parameters).For both groups,the levels of plasma ET-1 were positively correlated with values of mPAP,RVOT,and RV(r = 0.710,0.853,and 0.766,respectively,all P = 0.000),and negatively correlated with plasma NO and PaO_2(r =- 0.823,and- 0.752,respectively,all P = 0.000).Conclusion Ligustrazine is effective in treating pulmonary artery hypertension during acute exacerbation of COPD and CCP in patients from the plateau area.The observed changes in the plasma levels of NO and ET-1 in response to ligustrazine treatment suggest that ligustrazine may act through the selective effect on pulmonary blood vessels to enhance the synthesis and release of NO and suppress those of ET-1 from lung vascular endothelial cells,thus reducing pulmonary artery pressure and decreasing pulmonary arterial hypertension.
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 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.