1.Primary astroeytes with mutant SOD1G93A are susceptible to oxidative stress
Weisong DUAN ; Hui BU ; Yansu GUO ; Zhongyao LI ; Chunyan LI
Basic & Clinical Medicine 2010;30(4):378-382
Objective To study the vulnerability of astrocytes bearing mutant SOD1 under the oxidative stress.Methods The cytotoxicity of the serum deprived astrocytes was measured by MTT.The level of ROS was shown by fluorescence of DCF through confocal microscopy.The expression of Nrf2,HO1 and NQO1 in the different cells was detected by Western blot.Results The level of cellular toxicity was higher in the astrocytes bearing mutant SOD1 exposed to the oxidative stress than the astrocytes hearing wild type SOD1.In the astrocytes bearing mutant SOD1,the expression of Nrf2,HO1 and NQO1 decreased.In the presence of mutant SOD1,an unexpected 44 per-cent decrease of Nrf2 was detected.This was associated with a decreases in multiple downstream phase Ⅱ detoxif-ying enzymes and antioxidant enzymes,known as NQO1 and HO1.Furthermore,our results showed that the ex-pression of NQO1 increased 1.5 and 2.5-fold by EGCG at 5 and 10 μmol/L.EGCG also elevated the expression of total Nrf2.Confocal microscopy showed that EGCG caused Nrf2 translocation from the cytoplasm to the nucleus.Conclusion Decrease in Nrf2 expression is the mechanism to explain the vulnerability of astrocytes bearing mutant SOD1 and EGCG strengthened antioxidation function by upregulating the activity of Nrf2.
2.Apoptosis of Neuron Surrounding Intracerebral Hemorrhage in Rats
Hongling LI ; Yanping GE ; Yansu GUO ; Dongxia WU ; Chunyan LI
Chinese Journal of Rehabilitation Theory and Practice 2008;14(3):206-208
Objective To investigate the apoptosis of neuron surrounding the hematoma in intracerebral hemorrhage(ICH)rats.Methods 64 male SD rats were randomly divided into two groups,trial group(ICH,n=56)and control group(sham operated,n=8).The brains of the rats were removed 6 h,12 h,24 h,48 h,72 h,7 d,14 d after ICH.Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-bioti in situ nick end-labeling(TUNEL)was used to detect deoxyribonucleic acid(DNA)fragmentation.The activation of caspase-3 was measured with immunohistochemistery.The electron microscope were used to observe histological changes surrounding the hematoma.Results Under transmission electronic microscope,shrunken neuron and glial cell with pre-apoptotic signs of intensely stained cytoplasm and abnormally dense nucleus,swollen blood vessel were found.TUNEL-positive cells appeared in the periphery of the hematoma and increased from 6 h to 14 d after ICH.Little TUNEL-positive cells could be found in the control group.The change of the caspase-3-positive cells was similar to TUNEL,but the peak of caspase-3-positive cells was more early than that of TUNEL.Conclusion The apoptosis of neuron occurred surrounding the hematoma in ICH rats and it may related to caspase-3.
3.Expressions of Akt and glycogen synthase kinase-3β in the hippocampus after repetitive bilateral common carotid artery occlusion in mice
Mingyue FAN ; Yansu GUO ; Xiaomei MENG ; Ling LI ; Yanhong DONG ; Wenzhu CUI ; Peiyuan LV
International Journal of Cerebrovascular Diseases 2012;20(8):583-588
Objective To investigate the expressions of protein kinase B (PKB/Akt) and glycogen synthase kinasc-3β in the hippocampus in mice with vascular dementia (VaD) induced by repetitive bilateral common carotid artery occlusion.Methods Forty-eight healthy adult male C57B1/6 mice were randomly allocated into 3 group:normal group,sham operation group,and model group (n =16 in each group).A mouse VaD model was induced by intermittent blocking the bilateral common carotid artery for 3 times in the model group.The sham group only separated the bilateral common carotid artery,but did not block it.The normal group did not receive any treatment.The behavioral changes of the mice were observed using the water maze and step-down tests at 4 weeks after procedure.HE staining was used to observe the histopathological changes of hippocampal tissue.The Western blotting was used to detect the expressions of Akt,p-Akt (Ser473),GSK3β and p-GSK3β (Ser9) proteins.Results In the water maze test,the time of swimming the entire distance was prolonged at the learning stage and memory stage (learning stage:F =19.389,P <0.05; memory stage:F =27.929,P < 0.05),the number of errors increased (learning stage:F =7.228,P < 0.05; memory stage:F =21.189,P<0.05) in the model group.In the step-down test,the response time was prolonged (F=19.162,P <0.05) at learning stage and the number of errors increased (F =6.562,P < 0.05),the latency time was shortened (F=10.634,P<0.05) and the number of errors increased (F=12.890,P<0.05) in the model group.At the same time,HE staining showed the reduction of neurons and the proliferation of glial cells in the hippocampal CA1 region in the model group; p-Akt (Ser473) (F=37.849,P<0.05) and p-GSK3β (Ser9)(F =67.725,P <0.05) protein expressions were up-regulated significantly (F =37.849,P <0.05; F =67.725,P<0.05) at 4 weeks after procedure compared to those in the sham operation group,while there were no significant differences in Akt (F =1.004,P >0.05) and GSK3β(F =0.329,P >0.05) total protein expressions among all groups.Conclusions The repetitive bilateral common carotid artery occlusion may result in learning and memory impairment and severe damage in the hippocampus in mice.The Akt and GSK3β expressions may be involved in the mechanism of VaD.
5.The epidemiology and prediction of brain tumors incidence and mortality in China
Shaoyuan LEI ; Yulong LI ; Fei SUN ; Hongjun LIU ; Yue WU ; Yansu GUO
Basic & Clinical Medicine 2024;44(4):454-458
Objective To describe the incidence and mortality of brain tumors in China in 2020 and to predict the disease burden up to 2040.Methods The brain tumor incidence and mortality in 2020 were recorded based on the data from International Agency for Cancer Research(IARC),Cancer Today database.The incidence and mortality were standardized by age using Segi's world standard population.The burden of brain tumors in 2040 was predicted with assuming that national rates remained constant in 2020.Results It was estimated there were approximately 79 600 new brain tumors cases and 65 200 deaths in China in 2020.The age-standardized incidence and mortality rates of brain tumors in China were 4.1/100 000 and 3.2/100 000,respectively,which were lower than the United States of America,most of European countries and Australia.The incidence and mortality were higher than Africa,central America,and the Caribbean.From 2020 to 2040,the brain tumors cases and deaths are predicted to have an increase as 32.1%and 41.5%respectively.Conclusions The disease burden of brain tumors was still heavy in China.Further studies are urgently needed to clarify the epidemic trend of tissue typing and risk factors of brain tumors,which may support the development of effective prevention strategies.
6.Recent advance in role of ubiquitin-specific protease 11 in central nervous system diseases
Xinyan DU ; Zhongzhong LI ; Yansu GUO
Chinese Journal of Neuromedicine 2023;22(12):1272-1276
Ubiquitin-specific protease 11 (USP11) is a family member of deubiquitylases (DUBs). It mediates substrates de-ubiquitination to inhibit their ubiquitin-proteasome degradation and participates in cell cycle process, DNA damage repair, cell death, autophagy, signal transduction, immune inflammatory response, cerebral cortex development, and other physiological processes. Studies show that USP11 also plays an important role in central nervous system diseases. This article starts with the structure and functions of USP11 to systematically review the mechanism of USP11 in central nervous system diseases and provide new ideas for USP11 as a therapeutic target.
7.Basic and translational aging research in China: present and future.
Xiaojuan HE ; Moshi SONG ; Jing QU ; Yansu GUO ; Heqi CAO ; Ruijuan SUN ; Guang-Hui LIU ; Yong SHEN ; Major Program Expert Group
Protein & Cell 2019;10(7):476-484