Background:Oxidative stress in placenta is associated with the occurrence of adverse pregnancy outcomes in sow,but there are few satisfactory treatment strategies for these conditions.This study investigated the poten...Background:Oxidative stress in placenta is associated with the occurrence of adverse pregnancy outcomes in sow,but there are few satisfactory treatment strategies for these conditions.This study investigated the potential of cysteamine(CS)as an antioxidant protectant for regulating the reproductive performance,redox status,and placental angiogenesis of sows.Methods:The placental oxidative stress status and vascular density of piglets with different birth weights:<1.0 kg(low birth weight,LBW)and 1.4–1.6 kg(normal birth weight,NBW)were evaluated,followed by allotting 84 sows to four treatments(n=21)and feeding them with a basal diet supplemented with 0,100,300,or 500 mg/kg of CS from d 85 of gestation to d 21 of lactation,respectively.Placenta,serum,and colostrum samples of sows or piglets were collected,and the characteristics of sows and piglets were recorded.Furthermore,the in vivo results were validated using porcine vascular endothelial cells(PVECs).Results:Compared with the NBW placentae,the LBW placentae showed increased oxidative damage and were vulnerable to angiogenesis impairment.Particularly,H2O2-induced oxidative stress prompted intracellular reactive oxygen species generation and inhibited the tube formation and migration of PVECs as well as the expression of vascular endothelial growth factor-A(VEGF-A)in vitro.However,dietary CS supplementation can alleviate oxidative stress and improve the reproductive performance of sows.Specifically,compared with the control group,dietary 100 mg/kg CS could(1)decrease the stillbirth and invalid rates,and increase both the piglet birth weight in the low yield sows and the placental efficiency;(2)increase glutathione and reduce malondialdehyde in both the serum and the colostrum of sows;(3)increase the levels of total antioxidant capacity and glutathione in LBW placentae;(4)increase the vascular density,the mRNA level of VEGF-A,and the immune-staining intensity of platelet endothelial cell adhesion molecule-1 in the LBW placentae.Furthermore,the in vitro experiment indicated that CS pre-treatment could significantly reverse the NADPH oxidase 2-ROS-mediated inactivation of signal transducer and activator of transcription-3(Stat3)signaling pathway induced by H2O2 inhibition of the proliferation,tube formation,and migration of PVECs.Meanwhile,inhibition of Stat3 significantly decreased the cell viability,tube formation and the VEGF-A protein level in CS pretreated with H_(2)O_(2)-cultured PVECs.Conclusions:The results indicated that oxidative stress and impaired angiogenesis might contribute to the occurrence of LBW piglets during pregnancy,but CS supplementation at 100 mg/kg during late gestation and lactation of sows could alleviate oxidative stress and enhance angiogenesis in placenta,thereby increasing birth weight in low yield sows and reducing stillbirth rate.The in vitro data showed that the underlying mechanism for the positive effects of CS might be related to the activation of Stat3 in PVECs.展开更多
Dedifferentiation of mature vascular smooth muscle cells(SMCs)into immature cells capable of migrating and prolif-erating is one of the1 most important reasons for intimal thickening during the development of atherosc...Dedifferentiation of mature vascular smooth muscle cells(SMCs)into immature cells capable of migrating and prolif-erating is one of the1 most important reasons for intimal thickening during the development of atherosclerosis and restenosis after angioplasty.Similar conversion,termed"phenotypic modulation",occurs when.the;mature SMCs un-dergo primary culture,This 1 makes;SMC culture being a widely used model for intimal thickening.To determine if there is an intrinsic relationship between the SMC phenotypic modulation and dedifferentiation,the present study investi-gated the dynamic changes in cytoplasmic volume fraction of myofilaments and expressions of contractile proteins in cul-tured rabbit aortic SMCs with morphometric electron micros-copy and Western blot analysis.展开更多
Objective:Try to demonstrate the protection of cellular dam-age in a model of the ischemia/reperfusion(I/R)of cultured rat myocardium by exogenous micro norepinephrine precon-ditioning(NEPC),so as to provide some expe...Objective:Try to demonstrate the protection of cellular dam-age in a model of the ischemia/reperfusion(I/R)of cultured rat myocardium by exogenous micro norepinephrine precon-ditioning(NEPC),so as to provide some experimental infor-mation for an new non-injury preconditioning.Method:The apex of neonatal rat(3-4 days old)were taken,scissored、digested by 0.08%pancreatin,centrifugalized and trans-formed cell suspension.After this,the cell suspension were inoculated to culture flasks and were cultured by routine method for 5 days.展开更多
The adenosine preconditioning and ex-adenosine-the sulfuric acid adenine protection on I/R myocardium already has been reported,but the researches much lay emphasizing in myo-cardium.It is still not clear for sulfuric...The adenosine preconditioning and ex-adenosine-the sulfuric acid adenine protection on I/R myocardium already has been reported,but the researches much lay emphasizing in myo-cardium.It is still not clear for sulfuric acid adenine to influ-ence on 1/R myocardial interstitial.For this,this experiment use two-dimension image point analyzing method to measure the cross section areas of myocardial capillaries of myocardial interstitial,meanswhile,at each animal 0f each group,and take a piece of 2 ten thousand times photograph(all to six each group)to study fiber distribution of rat myocardial in-terstitial and to evaluate its significance.展开更多
基金funded by Project of National Natural Science Foundation of China(No.31872985 and 31790411)Natural Science Foundation of Guangdong Province(No.2021A1515012116).
文摘Background:Oxidative stress in placenta is associated with the occurrence of adverse pregnancy outcomes in sow,but there are few satisfactory treatment strategies for these conditions.This study investigated the potential of cysteamine(CS)as an antioxidant protectant for regulating the reproductive performance,redox status,and placental angiogenesis of sows.Methods:The placental oxidative stress status and vascular density of piglets with different birth weights:<1.0 kg(low birth weight,LBW)and 1.4–1.6 kg(normal birth weight,NBW)were evaluated,followed by allotting 84 sows to four treatments(n=21)and feeding them with a basal diet supplemented with 0,100,300,or 500 mg/kg of CS from d 85 of gestation to d 21 of lactation,respectively.Placenta,serum,and colostrum samples of sows or piglets were collected,and the characteristics of sows and piglets were recorded.Furthermore,the in vivo results were validated using porcine vascular endothelial cells(PVECs).Results:Compared with the NBW placentae,the LBW placentae showed increased oxidative damage and were vulnerable to angiogenesis impairment.Particularly,H2O2-induced oxidative stress prompted intracellular reactive oxygen species generation and inhibited the tube formation and migration of PVECs as well as the expression of vascular endothelial growth factor-A(VEGF-A)in vitro.However,dietary CS supplementation can alleviate oxidative stress and improve the reproductive performance of sows.Specifically,compared with the control group,dietary 100 mg/kg CS could(1)decrease the stillbirth and invalid rates,and increase both the piglet birth weight in the low yield sows and the placental efficiency;(2)increase glutathione and reduce malondialdehyde in both the serum and the colostrum of sows;(3)increase the levels of total antioxidant capacity and glutathione in LBW placentae;(4)increase the vascular density,the mRNA level of VEGF-A,and the immune-staining intensity of platelet endothelial cell adhesion molecule-1 in the LBW placentae.Furthermore,the in vitro experiment indicated that CS pre-treatment could significantly reverse the NADPH oxidase 2-ROS-mediated inactivation of signal transducer and activator of transcription-3(Stat3)signaling pathway induced by H2O2 inhibition of the proliferation,tube formation,and migration of PVECs.Meanwhile,inhibition of Stat3 significantly decreased the cell viability,tube formation and the VEGF-A protein level in CS pretreated with H_(2)O_(2)-cultured PVECs.Conclusions:The results indicated that oxidative stress and impaired angiogenesis might contribute to the occurrence of LBW piglets during pregnancy,but CS supplementation at 100 mg/kg during late gestation and lactation of sows could alleviate oxidative stress and enhance angiogenesis in placenta,thereby increasing birth weight in low yield sows and reducing stillbirth rate.The in vitro data showed that the underlying mechanism for the positive effects of CS might be related to the activation of Stat3 in PVECs.
文摘Dedifferentiation of mature vascular smooth muscle cells(SMCs)into immature cells capable of migrating and prolif-erating is one of the1 most important reasons for intimal thickening during the development of atherosclerosis and restenosis after angioplasty.Similar conversion,termed"phenotypic modulation",occurs when.the;mature SMCs un-dergo primary culture,This 1 makes;SMC culture being a widely used model for intimal thickening.To determine if there is an intrinsic relationship between the SMC phenotypic modulation and dedifferentiation,the present study investi-gated the dynamic changes in cytoplasmic volume fraction of myofilaments and expressions of contractile proteins in cul-tured rabbit aortic SMCs with morphometric electron micros-copy and Western blot analysis.
文摘Objective:Try to demonstrate the protection of cellular dam-age in a model of the ischemia/reperfusion(I/R)of cultured rat myocardium by exogenous micro norepinephrine precon-ditioning(NEPC),so as to provide some experimental infor-mation for an new non-injury preconditioning.Method:The apex of neonatal rat(3-4 days old)were taken,scissored、digested by 0.08%pancreatin,centrifugalized and trans-formed cell suspension.After this,the cell suspension were inoculated to culture flasks and were cultured by routine method for 5 days.
文摘The adenosine preconditioning and ex-adenosine-the sulfuric acid adenine protection on I/R myocardium already has been reported,but the researches much lay emphasizing in myo-cardium.It is still not clear for sulfuric acid adenine to influ-ence on 1/R myocardial interstitial.For this,this experiment use two-dimension image point analyzing method to measure the cross section areas of myocardial capillaries of myocardial interstitial,meanswhile,at each animal 0f each group,and take a piece of 2 ten thousand times photograph(all to six each group)to study fiber distribution of rat myocardial in-terstitial and to evaluate its significance.
