The action mechanism by which C1q/tumor necrosis factor-related protein-6 alleviates cerebral ischemia/reperfusion injury in diabetic mice

Studies have shown that C1q/tumor necrosis factor-related protein-6 (CTRP6) can alleviate renal ischemia/reperfusion injury in mice. However, its role in the brain remains poorly understood. To investigate the role of CTRP6 in cerebral ischemia/reperfusion injury associated with diabetes mellitus, a diabetes mellitus mouse model of cerebral ischemia/reperfusion injury was established by occlusion of the middle cerebral artery. To overexpress CTRP6 in the brain, an adeno-associated virus carrying CTRP6 was injected into the lateral ventricle. The result was that oxygen injury and inflammation in brain tissue were clearly attenuated, and the number of neurons was greatly reduced. In vitro experiments showed that CTRP6 knockout exacerbated oxidative damage, inflammatory reaction, and apoptosis in cerebral cortical neurons in high glucose hypoxia-simulated diabetic cerebral ischemia/reperfusion injury. CTRP6 overexpression enhanced the sirtuin-1 signaling pathway in diabetic brains after ischemia/reperfusion injury. To investigate the mechanism underlying these effects, we examined mice with depletion of brain tissue-specific sirtuin-1. CTRP6-like protection was achieved by activating the sirtuin-1 signaling pathway. Taken together, these results indicate that CTRP6 likely attenuates cerebral ischemia/reperfusion injury through activation of the sirtuin-1 signaling pathway.

Preventive and therapeutic effect of simvastatin on secondary inflammatory damage of rats with cerebral hemorrhage

Objective:To investigate the preventive and therapeutic effect and mechanism of simvastatin on secondary inflammatory damage of rats with cerebral hemorrhage.Methods:Sixty SD rat aged 9-12 weeks were chosen and divided into the control group,model group and simvastatintreated group randomly with 20 rats in each group.Rats in the model group and simvastatintreated group were infused with autologous fresh uncoagulated blood to the right brain tissue of the basal ganglia to build the cerebral hemorrhage model,while rats in the control group were treated with the same amount of normal saline.Then,rats in the simvastatin-treated group were given a gavage of 3 mg/kg of simvastatin once a day after modeling.Rats in the three groups were given nerve dysfunction score(NDS) and wet-dry weighting method was used to detect the brain water content(BWC) of brain tissues around the lesion of the rats.Then Nissl staining was conducted and the undamaged neurons were counted.Immunohistochemical SP method was applied to count the number of NF-d the immuno fluorκB,TLR4 and IL-1escence method wasβ positive cells in brain tissues around the lesions,an employed to determine the expression levels of NF-κB,TLR4 and IL-1me points were aβ proteins.Results:The NDS results of the simvastatin-treated group at all till significantly higher than those of the model group(P < 0.05);the BWC values of the simvastatin-treated group at all time points were all significantly lower than those of the model group at the same periods(P < 0.05);the number of the undamaged neurons around the lesions of the simvastatin-treated group at all time points were all significantly higher than those of the model group(P < 0.05);seven days after treatment,the number of the NF-κB,TLR4 and IL-1β positive cells in brain tissues around the lesions of the simvastatin-treated group were all significantly lower than those of the model group(P < 0.05),and its expression levels of NF-ower than those of the model group(κB,TLR4 and IL-1P < 0.05).Conclusioβ protein were also significantly lns:Simvastatin can inhibit the expressions of NF-κB,TLR4 and IL-1β proteins in rats with cerebral hemorrhage,and protect neurons and reduce secondary inflammatory damages by down-regulating the above protein-mediated inflammatory responses.

Coexistence of hyperlipidemia and acute cerebral ischemia/reperfusion induces severe liver damage in a rat model

AIM:To investigate the correlation of hyperlipemia(HL) and acute cerebral ischemia/reperfusion(I/R) injury on liver damage and its mechanism.METHODS:Rats were divided into 4 groups:control,HL,I/R and HL+I/R.After the induction of HL via a high-fat diet for 18 wk,middle cerebral artery occlusion was followed by 24 h of reperfusion to capture I/R.Serum alanine transaminase(ALT) and aspartate aminotransferase(AST) were analyzed as part of liver function tests and liver damage was further assessed by histological examination.Hepatocyte apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick-end labeling(TUNEL) assay.The expression of genes related to apoptosis(caspase-3,bcl-2) was assayed by immunohistochemistry and Western blotting.Serum tumor necrosis factor-(TNF-),interleukin-1(IL-1) and liver mitochondrial superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),malondialdehyde(MDA) and Ca 2+ levels were measured to determine inflammatory and oxidative/antioxidative status respectively.Microsomal hydroxylase activity of the cytochrome P450 2E1(CYP2E1)-containing enzyme was measured with aniline as the substrate,and CYP2E1 expression in the liver tissue and microsome was determined by immunohistochemistry and Western blotting respectively.RESULTS:HL alone induced by high-fat diet for 18 wk resulted in liver damage,indicated by histopathological analysis,and a considerable increase in serum ALT(25.13 ± 16.90 vs 9.56 ± 1.99,P < 0.01) and AST levels(18.01 ± 10.00 vs 11.33 ± 4.17,P < 0.05) compared with control.Moreover,HL alone induced hepatocyte apoptosis,which was determined by increased TUNEL-positive cells(4.47 ± 0.45 vs 1.5 ± 0.22,P < 0.01),higher caspase-3 and lower bcl-2 expression.Interestingly,compared with those in control,HL or I/R groups,massive increases of serum ALT(93.62 ± 24.00 vs 9.56 ± 1.99,25.13 ± 16.90 or 12.93 ± 6.14,P < 0.01) and AST(82.32 ± 26.92 vs 11.33 ± 4.17,18.01 ± 10.00 or 14.00 ± 6.19,P < 0.01) levels in HL+I/R group were observed suggesting severe liver damage,which was confirmed by liver histology.In addition,HL combined with I/R also caused significantly increased hepatocyte apoptosis,as evidenced by increased TUNEL-positive cells(6.20 ± 0.29 vs 1.5 ± 0.22,4.47 ± 0.45 or 1.97 ± 0.47,P < 0.01),elevated expression of caspase-3 and lower expression of bcl-2.Furthermore,when compared to HL or I/R alone,HL plus I/R enhanced serum TNF-,IL-1,liver mitochondrial MDA and Ca 2+ levels,suppressed SOD and GSH-Px in liver mitochondria,and markedly up-regulated the activity(11.76 ± 2.36 vs 4.77 ± 2.31 or 3.11 ± 1.35,P < 0.01) and expression(3.24 ± 0.38 vs 1.98 ± 0.88 or 1.72 ± 0.58,P < 0.01) of CYP2E1 in liver.CONCLUSION:The coexistence of HL and acute cerebral I/R induces severe liver damage,suggesting that cerebral ischemic stroke would exaggerate the damage of liver caused by HL.This effect is possibly due to en-hanced CYP2E1 induction which further promotes oxidative damage,inflammation and hepatocyte apoptosis.

Mechanism underlying the protective effect of Kaixin Jieyu Fang on vascular depression following cerebral white matter damage

The Chinese compound Kaixin fieyu Fang can be used to treat vascular depression; however, the underlying mechanism remains unclear. This study established a rat model of chronic cerebral ischemia-caused white matter damage by ligation of the bilateral common carotid arteries. Rats received daily intragastric administration of a suspension of Kaixin ]ieyu Fang powder. After 3, 7 and 21 days of treatment, the degree of white matter damage in the cerebral ischemia rat model was alleviated, Bcl-2 protein and mRNA expression in brain tissue increased, and Bax protein and mRNA expression decreased. These results indicate that Kaixin Jieyu Fang can alleviate cere- bral white matter damage, and the underlying mechanism is associated with regulation of Bcl-2/ Bax protein and mRNA expression, which is one of possible mechanism behind the protective effect of Kaixin Jieyu Fang against vascular depression.

Inhibition of NLRP3 inflammasomes reduced blood brain barrier damage by DHA during early acute cerebralischemia

The aim of this study was to explore the neuroprotective effect and mechanism of DHA on cerebral ischemia injury and blood-brain barrier(BBB)disruption.the focal cerebral I/R model was established by middle cerebral artery oclusion(MCAO).BBB permeability was assessed with the leaking amount of Evans Blue and the expression of occludin and ZO-1.The expression of pyrin domain containing(NLRP3)was checked to explore the inhibition of inflammation by DHA.The results showed that DHA could significantly reduce cortical and sub-cortical infarct volumes,neurologic de ficit scores,cerebral edema,BBB permeability after I/R injury.Leaking amount of Evans Blue was reduced by DHA,and occludin and ZO-1 were up-regulated by DHA.The expression of NLRP3 was inhibited after exposure of DHA.Our results indicated that DHA could effectively penetrate the brain of MCAO rats,aleviated the I/R injury by inhibiting NLRP3 inflammasomes and improve BBB disruption,showing a great clinical potential for stroke.

Changes in the permeability of blood brain barrier and endothelial cell damage after cerebral ischemia

OBJECTIVE： To investigate the effect of endothelial cells on the permeability of blood brain barrier （BBB） after brain injury and its effect mechanism. DATA SOURCES： We searched for the articles of permeability of BBB and endothelial cell injury after brain is- chemia, which were published between January 1982 and December 2005, with the key words of ＂cerebral ischemia damage,blood brain barrier （ BBB）,permeability,effect of endothelial cell （EC） and its variation mechanism＂in English. STUDY SELECTION： The materials were primarily selected. The articles related to the changes in the permeability of BBB and the effect of endothelial cells as well as the change mechanism after cerebral ischemia damage were chosen. Repetitive studies or review articles were excluded. DATA EXTRACTION： Totally 55 related articles were collected, and 35 were excluded due to repetitive or review articles, finally 20 articles were involved. DATA SYNTHESIS： The content or viewpoints of involved literatures were analyzed. Cerebral ischemia had damage for endothelial cells, such as the inflow of a lot of Ca2^＋, the production of nitrogen monoxide and oxygen free radical, and aggravated destruction of BBB. After acceptors of inflammatory mediators on cerebrovascular endothelial cell membrane, such as histamine, bradykinin , 5-hydroxytryptamine and so on are activated, endothelial cells shrink and the permeability of BBB increases. Its mechanism involves in the inflow of extracellular Ca^＋2and the release of intracellular Ca^2＋ in the cells. Glycocalyx molecule on the surface of endothelial cell, having structural polytropy, is the determinative factor of the permeability of BBB. VEGF, intensively increasing the vasopermeability and mainly effecting on postcapillary vein and veinlet, is the strongest known blood vessel permeation reagent. Its chronic overexpression in the brain can lead the destruction of BBB. CONCLUSION： The injury of endothelial cell participants in the pathological mechanism of BBB destruction after cerebral ischemla.

Thrombolytic activity of cheonggukjang kinase in recovery from brain damage in a rat cerebral embolic stroke model

Cheonggukjang is a soybean paste made by fermenting whole cooked soybeans with Bacillus subtilis. Cheonggukjang contains a fibrinolytic enzyme that could provide clinical applications for removing blood clots. In the present study, the term ＂cheonggukjang kinase＂ （CGK） was used to refer to this fibrinolytic enzyme. The thrombolytic effects of CGK were analyzed in a rat model of cerebral embolic stroke produced by middle cerebral artery occlusion （MCAO）. Results from fibrin and platelet-rich clot lysis assays demonstrated that thrombolytic activity was greatest in CGKs, which were cultured for 40 hours. In addition, T50, the time needed to decompose 50% of the clot, did not change with plasminogen treatment, indicating that CGK was not a plasminogen activator, but was rather presumed to act as a plasmin-like protein. An intravenous infusion of CGK （1 U plasmin-like activity/100 μg CGK/kg） at 1 hour after MCAO resulted in removal of clots in a rat model of cerebral embolic stroke. CGK-treated groups exhibited a significant dose-dependent reduction in infarct volume. CGK treatment also improved functional recovery, as assessed by neurological deficit scores. Decreased infarct volume and improved functional recovery following CGK treatment was greater compared with recombinant tissue plasminogen activator （10 mg/kg）. These results suggested that CGK effectively reduced infarct volume and improved functional recovery following ischemic brain injury. CGK exhibits a number of potential clinical applications ir the treatment of cerebral embolic stroke.

Heme as an inducer of cerebral damage in hemorrhagic stroke:potential therapeutic implications

Intracerebral hemorrhage(ICH)consists of the rupture of a cerebral artery leading to bleeding into the surrounding parenchyma.This event has a primary phase of brain injury consisting of mechanical tissue damage due to the mass effect,followed by a secondary phase of brain injury triggered by the presence of blood components released at the site of bleeding(Bulters et al.,2018).Despite the high rates of mortality and morbidity from ICH,no effective treatment is available so far.

Corrigendum:Resveratrol inhibits matrix metalloproteinases to attenuate neuronal damage in cerebral ischemia:a molecular docking study exploring possible neuroprotection

In the article titled“Resveratrol inhibits matrix metalloproteinases to attenuate neuronal damage in cerebral ischemia:a molecular docking study exploring possible neuroprotection”,published on pages 568–575,Issue 4,Volume 10 of Neural Regeneration Research(Pandey et al.,2015),Figure 1B images were provided incorrectly.The correct images of Figure 1B are shown below.

Expression of Concern:Resveratrol inhibits matrix metalloproteinases to attenuate neuronal damage in cerebral ischemia:a molecular docking study exploring possible neuroprotection

On 30 April, 2015, Neural Regeneration Research(NRR) published the article "Resveratrol inhibits matrix metalloproteinases to attenuate neuronal damage in cerebral ischemia: a molecular docking study exploring possible neuroprotection" by Pandey et al.(2015;doi: 10.4103/1673-5374.155429). After publication, we received emails from one independent source regarding Figure 1 B with the exception of the first subfigure and the subfigures of the lower panel in Figure 1 B appear similar or duplication of images from Figures 1 and 2 published in Brain Research(Pandey et al., 2011) by the same first author.

Single-strand DNA damages and its relationship with morphological change of neurons at early stage of rat cerebral ischemia/reperf usion

Objective：To discuss the DNA-strand breaks at early stage of middle cerebral artery occlusion/reperfusion (MCAO/R). Methods: Neurons number and morphologic change were observed by Nissl stain method, and DNA strand breaks were in situ detected by using DNA polymerase- I Klenow fragment-mediat-ed nick end-labelling method (Klenow method). Results: Six hours after reperfusion, a few neurons in dam-aged regions appeared morphologic changes while a few Klenow-positive cells were detected (P<0. 01). Twenty-four hours after reperfusion lots of neurons showed morphologic change while the number of Klenow-positive cells immediately and remarkably increased (P<0. 01). Seventy-two hours after reperfusion the number of neurons decreased significantly and the number of Klenow-positive cells was also less than that in 24 h (P<0. 05). Conclusion: ① 24 h after reperfusion when the number of Klenow-positive cells reached peak value, DNA single-strand breaks (SSBs) took place in many Klenow-positive cells, and presumed that DNA SSBs might be an important step in DNA-damage procession which might be induced by free radicals. ② At the same time when lots of DNA SSBs were produced, many neurons in the damaged regions showed morphological change, which indicated that lots of neurons had already progressed to irreversible damages when DNA SSBs took place.

Methylene blue attenuates white matter damage after focal cerebral ischemia-reperfusion in rats

Methylene blue(MB)was reported to have neuronal protective effect after brain ischermia.In this study,we aimed to investigate the effect of MB on white matter in rats after focal cerebral ischemia-reperfusion(MCAO/R)injury.MCAO/R model was set and 54 male SD rats were randomly divided into 3 groups:control(sham surgery group),middle cerebral artery occlusion and reperfusion(MCAO),MCAO treated with MB of 10 mg/kg(MB)by intraperitoneal injection 1.5 h after surgery.We observed the neurological deficits in different groups using foot fault test 24 h after MCAO.We measured the infarction volume using TTC staining and showed the morphological changes of neurons and myelin using Nissl and black gold staining.

Correlation of carotid contrast-enhanced ultrasonography parameters with nerve damage and plaque properties in patients with atherosclerosis cerebral infarction

Objective: To explore the correlation of carotid contrast-enhanced ultrasonography parameters with nerve damage and plaque properties in patients with atherosclerosis cerebral infarction. Methods: A total of 176 patients with atherosclerosis cerebral infarction who were sent to this hospital for medical treatment between August 2014 and February 2018 were enrolled in cerebral infarction group, and 100 healthy elderly subjects who received physical examination in this hospital during the same period were enrolled in normal control group. Carotid CEUS parameter levels as well as serum contents of indexes related to nerve injury and plaque property were compared between the two groups, and Pearson test was used to evaluate the correlation of CEUS parameters levels with nerve damage and plaque properties in patients with cerebral infarction. Results: CEUS parameter Tp level in cerebral infarction group was lower than that in normal control group whereas P and AUC levels were higher than those in normal control group;serum nerve damage-related indexes SAA, NT-proBNP, Hcy, NSE and copeptin contents were higher than those of normal control group;serum plaque property-related indexes Lp-PLA2, MMP-9, Cat S and CD62P contents were higher than those of normal control group while APN and Cys C contents were lower than those of normal control group. Correlation analysis confirmed that carotid CEUS parameter levels in patients with cerebral infarction were correlated with the contents of indexes related to nerve damage and plaque property. Conclusion: Carotid CEUS parameters are obviously abnormal in patients with atherosclerosis cerebral infarction, they are directly correlated with the specific nerve damage and plaque properties, and they can be used as the reliable indexes to forecast the risk of cerebral infarction and evaluate its severity.

Correlation of peripheral blood T cell changes with nerve damage, inflammatory response and stress response in patients with acute cerebral infarction

Objective: To investigate the correlation of peripheral blood T cell changes with nerve damage, inflammatory response and stress response in patients with acute cerebral infarction. Methods: 108 patients with acute cerebral infarction who received emergency treatment in Xuefu Hospital of Shaanxi Normal University between September 2015 and August 2017 were selected as the cerebral infarction group, and 100 healthy elderly volunteers who underwent physical examination during the same period were selected as the normal control group. The differences in the expressions of CD4+CD25+ regulatory T lymphocytes in peripheral blood as well as the levels of nerve damage indicators, inflammatory factors and oxidative stress indicators in serum were compared between the two groups. Pearson test was used to evaluate the intrinsic relationship between peripheral blood CD4+CD25+ regulatory T lymphocyte expression and infarction condition in patients with acute cerebral infarction. Results:Peripheral blood CD4+CD25+ regulatory T lymphocyte expression of the cerebral infarction group was higher than that of the normal control group;serum nerve damage indicators UCH-L1, GFAP, and Ang-1 levels were higher than those of the normal control group while IGF-1 and BDNF levels were lower than those of the normal control group;serum inflammatory factors IL-1β, VCAM-1, IL-13, and IL-18 levels were higher than those of the normal control group;serum oxidative stress indicators CAT and T-SOD levels were lower than those of the normal control group whereas MDA level was higher than that of the normal control group. Correlation analysis confirmed that peripheral blood CD4+CD25+ regulatory T lymphocyte expression in patients with acute cerebral infarction was directly correlated with the levels of nerve damage indicators, inflammatory factor, and oxidative stress indicators. Conclusion:The abnormal increase of peripheral blood CD4+CD25+ regulatory T lymphocyte expression in patients with acute cerebral infarction is related to the aggravation of nerve damage and systemic inflammatory stress response.

Transfusion of CXCR4-priming endothelial progenitor cells reduces cerebral ischemic damage and promotes angiogenesis and neurogenesis in db/db diabetic mice

Previous studies suggest that reduction and dysfunction of circulating endothelial progenitor cells(EPCs),and dysregulation in stromal cell derived factor-1/CXC-chemokine receptor 4(SDF-1/ CXCR4) axis in diabetes could be therapeutic targets for diabetic ischemic stroke.This study investigated the efficacy of CXCR4-priming EPCs on cerebral repair following ischemic stroke in db/db diabetic mice.Bone marrow derived EPCs from db/+ control mice were transfected with adenovirus(1×10~7 IU) carrying CXCR4(Ad-CXCR4-EPCs)or null(Ad- null-EPCs).The db/db mice were divided into three groups for EPCs injection(2×10~5 cells/100μl): Ad-CXCR4-EPCs,Ad-null-EPCs or saline(vehicle), via tail vein 2 hrs after middle cerebral artery occlusion (MCAO) surgery.Cerebral blood flow(CBF) was measured with laser Doppler flowmeter.Mice were sacrificed at 2 or 7 days thereafter.Level of circulating EPCs was measured by flow cytometry. Ischemic damage,cerebral microvascular density (MVD),angiogenesis and neurogenesis were determined by histological staining with Fluoro-J,CD31, CD31 +BrdU,NeuN +BrdU,GFAP+BrdU,respectively. Results(table) showed:1) Levels of CXCR4 expression were reduced in the brain and EPCs of db/db mice as measured by real-time RT-PCR and western blot analyses(data not shown);2) The level of circulating EPCs was more in the mice treated with Ad-CXCR4-EPCs;3)EPC transfusion improved CBF,increased MVD,angiogenesis and neurogenesis in peri-infarct area,and decreased ischemic damage.The efficacies were better in Ad-CXCR4 -EPCs group.Data suggest that transfusion of Ad-CXCR4-EPCs could be a therapeutic avenue for ischemia stroke in diabetes.

Influence of edaravone on growth arrest and DNA damage-inducible protein 34 expression following focal cerebral ischemia-reperfusion in rats

Objective:To investigate the influence of edaravone on the expression of growth arrest and DNA damage-inducible protein 34(GADD34).Methods:A total of 108 healthy male Sprague-Dawlcy rats were randomly divided into sham operation group,model group and edaravone.group(36 cases for each group).Transient focal cerebral ischemia was induced by middle cerebral artery occlusion for 2 h followed by reperfusion in Sprague-Dawlev rats.Then.GAOD34 expression was measured with immunohistochemistry at different time-points after reperfusion in the peri-infarct regions of all rats.Results:The GADD34 expression was detected in the peri-infaret regions of rats 1 h after reperfusion,which reached its peak 24 h after reperfusion.And edaravone could significantly down-regulate the GAOD34 expression.Conclusions:Edaravon could down-regulate GADD34 expression,which suggests that edaravone may exert an important function in inhibiting endoplasmic reticulum stress reaction by scavenging free radicals in the upper stream.

依托咪酯通过PI3K/AKT/eNOS信号通路抑制大鼠脑缺血再灌注后心肌损伤的研究

目的观察依托咪酯对大鼠脑缺血再灌注后心肌损伤的影响,及其作用机制。方法将SD大鼠随机分为假手术组、模型组和低、中、高剂量实验组,每组10只。模型组和低、中、高剂量实验组均用大脑中动脉阻塞(MCAO)方法建立脑缺血再灌注模型大鼠;假手术组仅暴露大脑中动脉,但不阻塞。在建模同时,低、中、高剂量实验组分别腹腔注射5、15、25 mg·kg^(-1)依托咪酯,假手术组与模型组均腹腔注射等体积0.9%NaCl。5组大鼠每天给药1次,连续给药14 d。用酶联免疫吸附试验法检测血清乳酸脱氢酶(LDH)、肌酸激酶同工酶(CK-MB)水平,用原位末端转移酶标记法检测心肌细胞凋亡率,用蛋白质印迹法检测心肌组织中蛋白激酶B(AKT)和内皮型一氧化氮合酶(eNOS)蛋白的表达水平。结果假手术组、模型组和低、中、高剂量实验组的血清LDH水平分别为(186.67±24.89)、(289.91±56.26)、(257.64±45.13)、(226.74±39.82)和(196.43±28.82)U·L^(-1),CK-MB水平分别为(17.81±3.41)、(36.89±7.75)、(31.18±6.31)、(25.21±5.88)和(19.94±4.38)U·L^(-1),心肌细胞凋亡率分别为(2.99±0.56)%、(13.51±2.37)%、(9.85±1.58)%、(5.92±0.84)%和(3.15±0.81)%,磷酸化AKT/AKT比值分别为0.12±0.02、0.24±0.04、0.39±0.06、0.52±0.07和0.97±0.08,磷酸化eNOS/eNOS比值分别为0.09±0.01、0.17±0.04、0.46±0.09、0.77±0.09和0.83±0.07。低、中、高剂量实验组和假手术组的上述指标与模型组比较,在统计学上差异均有统计学意义(均P<0.05)。结论依托咪酯通过激活PI3K/AKT/eNOS信号通路,减轻大鼠脑缺血再灌注后心肌损伤,从而发挥保护心功能的作用。

M1型小胶质细胞极化在大脑皮层梗死后继发丘脑损伤中的作用

目的探讨M1型小胶质细胞极化在大脑皮层梗死后继发丘脑损伤中的作用。方法使用电凝法制备成年雄性SD大鼠的局灶性皮层梗死模型,并将其随机分为假手术组和术后1~4周的不同时间点模型组。在评估各组大鼠神经功能改变的基础上,通过免疫组织化学和免疫荧光分别检测丘脑VPN区NeuN、GFAP、Iba-1和Iba-1^(+)/CD68^(+)(M1型小胶质细胞)及Iba-1^(+)/CD206^(+)(M2型小胶质细胞)阳性细胞数量和形态变化;通过免疫印迹检测丘脑VPN区IL-1β、TNF-α、IL-10和Arg-1表达水平。结果与假手术组相比,模型组4周时NeuN免疫阳性细胞减少(P<0.05),GFAP和Iba-1免疫阳性细胞增多(P<0.05),促炎因子TNF-α和IL-1β表达明显升高(P<0.05),神经功能学评分显著升高(P<0.05)。与M2型小胶质细胞相比,模型组4周梗死同侧丘脑VPN区M1型小胶质细胞显著增多(P<0.05)。结论M1型小胶质细胞极化可能参与了大脑皮层梗死后同侧丘脑损害的过程。

西地那非对脑出血所致病理损伤和神经功能缺损的影响

目的 探讨血管活性药物西地那非(SDNF)对脑出血小鼠脑影像、病理损伤及神经功能的影响。方法 24只2~3月龄C57Bl/6小鼠,采用脑立体注射胶原酶法构建脑出血(ICH)模型,随机分为溶剂组、SDNF组,分别给予生理盐水或等体积0.5 mg/kg的SDNF连续灌胃7 d,之后分别在第3、7、14天进行mNSS神经功能评分,第7天采用脑磁共振检查脑血肿体积,激光散斑脑血流仪检测脑血流。造模后第14天处死小鼠,采用血红蛋白检测试剂盒检测脑内血红蛋白含量,采用免疫荧光法检测血肿周围血管内皮细胞标记CD31的表达量。结果 SDNF组小鼠mNSS评分在第7、14天的评分(分别为6.17±1.19、2.75±1.21)较溶剂组(分别为8.50±1.12、4.83±0.93)显著减小(F_(交互)=6.49,P<0.001)。SDNF组小鼠脑内血肿体积、校正脑组织水肿率在第7天(分别为2.94±1.05、5.37±1.26)较溶剂组(分别为6.03±1.23、8.01±1.75)显著减小(t值分别为4.66、2.99,均P<0.05),相对脑血流量(82.50±5.17)显著高于溶剂组(73.50±7.56,P<0.05)。SDNF治疗组小鼠脑内血红蛋白含量在第14天(36.98±12.31)显著小于溶剂组(66.00±17.21,P<0.05),病理结果显示SDNF治疗组小鼠脑内血管内皮标记物CD31的表达量(34.72±8.22)显著高于溶剂组(23.00±8.60,P<0.05)。结论 SDNF可减轻小鼠脑出血后神经功能缺损症状,改善脑血流,促进血肿吸收,降低脑内血红蛋白的含量,促进血管内皮细胞再生,在脑出血治疗中具有潜在的临床应用价值。

急性脑缺血/再灌注损伤后神经元细胞骨架蛋白的动态变化

目的探讨急性脑缺血/再灌注大鼠神经元细胞骨架蛋白时空动态变化。方法线栓法阻断大鼠大脑中动脉90 min后实现再灌注,在不同再灌注时间点观察及取材。尼氏染色观察神经细胞损伤,采用神经功能缺损评分和前肢放置实验评估神经功能;免疫组化染色、免疫印迹法观察细胞骨架成分微管相关蛋白2(microtubule associated protein 2,MAP2)、神经丝重链(neurofilament heavy chain,NF-H)的变化;透射电镜观察轴突、树突和神经丝亚显微结构。结果随着再灌注时间的延长,脑损伤和神经行为功能损害逐渐加重。纹状体损伤比皮层出现的更早、更严重。缺血区域的MAP2相关免疫反应强度降低,NF-H相关免疫反应强度升高。超微结构观察显示细胞骨架排列受损,密度降低。结论不同脑区对缺血/再灌注损伤的耐受性不同。神经元细胞骨架的主要成分对缺血和再灌注表现出动态反应,这可能进一步促进脑损伤和神经功能缺损。