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1.
Brain energy disorders and oxidative stress due to chronic hypoperfusion were considered to be the major risk factors in the pathogenesis of dementia. In previous studies, we have demonstrated that acupuncture treatment improved cognitive function of VaD patients and multi-infarct dementia (MID) rats. Acupuncture therapy also increased the activities of glycometabolic enzymes in the brain. But it is not clear whether acupuncture treatment compensates neuronal energy deficit after cerebral ischemic through enhancing the activities of glucose metabolic enzymes and preserving mitochondrial function, and whether acupuncture neuroprotective effect is associated with activations of mitochondrial antioxidative defense system. So, the effect of acupuncture therapy on cognitive function, cerebral blood flow (CBF), mitochondrial respiratory function and oxidative stress in the brain of MID rats was investigated in this study. The results showed that acupuncture treatment significantly improved cognitive abilities and increased regional CBF of MID rats. Acupuncture elevated the activities of total SOD, CuZnSOD and MnSOD, decreased the level of malondialdehyde (MDA) and superoxide anion, regulated the ratio of reduced glutathione (GSH) and oxidized glutathione (GSSG) in mitochondria, and raised the level of the respiratory control index (RCI) and P/O ratio and the activities of mitochondrial respiratory enzymes of MID rats. These results indicated that acupuncture treatment improved cognitive function of MID rats; and this improvement might be due to increased CBF, which ameliorated mitochondrial dysfunction induced by ischemia and endogenous oxidative stress system of brain.  相似文献   
2.
目的:初步探讨旋转恒定磁场治疗急性骨髓型放射病的效果。方法:BALB/C小鼠按体重随机分为磁疗组和对照组,每组再各分为4组.分别接受0Gy、6.0Gy、8.0Gy、10.0Gy ^60COγ射线全身辐射,照后,对照组不作任何处理,磁疗组接受磁场处理30d,每天2次,每次1.5h,旋转磁场强度为0.6T,比较两组小鼠30d的存活率和存活期。结果:单纯磁场处理对正常小鼠生存状态及存活率无明显影响;10.0Gy组和8.0Gy组小鼠生存率磁疗组与对照组之间比较均无统计学差异(P〉0.05);6.0Gy组生存率磁疗组和对照组之间比较有统计学差异(P〈0.05),其磁疗组30d平均存活率为71.43%,平均存活期为(24.93±8.43)d,对照组30d平均存活率21.4l%.平均存活期为(17.07±7.70)d。结论:旋转恒定磁场不能提高10.0Gy及8.0Gy剂量所致极重度急性骨髓型放射病小鼠的生存率,但对6.0Gy所致重度急性骨髓型放射病有明显的保护作用,从而为旋转恒定磁场应用于临床治疗重度急性骨髓型放射损伤提供了实验依据。  相似文献   
3.
After significant injury, the liver must maintain homeostasis during the regenerative process. We hypothesized the existence of mechanisms to limit hepatocyte proliferation after injury to maintain metabolic and synthetic function. A screen for candidates revealed suppressor of cytokine signaling 2 (SOCS2), an inhibitor of growth hormone (GH) signaling, was strongly induced after partial hepatectomy. Using genetic deletion and administration of various factors we investigated the role of SOCS2 during liver regeneration. SOCS2 preserves liver function by restraining the first round of hepatocyte proliferation after partial hepatectomy by preventing increases in growth hormone receptor (GHR) via ubiquitination, suppressing GH pathway activity. At later times, SOCS2 enhances hepatocyte proliferation by modulating a decrease in serum insulin-like growth factor 1 (IGF-1) that allows GH release from the pituitary. SOCS2, therefore, plays a dual role in modulating the rate of hepatocyte proliferation. In particular, this is the first demonstration of an endogenous mechanism to limit hepatocyte proliferation after injury.  相似文献   
4.
铁过载促进小鼠肝组织发生蛋白质酪氨酸硝化   总被引:3,自引:0,他引:3  
蛋白质酪氨酸硝化是一种蛋白质翻译后的修饰,其存在会影响酶的催化活性,细胞信号转导和细胞骨架结构.在铁过载情况下,存在引起蛋白质酪氨酸硝化的有利环境,但目前尚无实验证实.本文运用腹腔注射右旋糖苷铁造成小鼠铁过载模型,通过免疫印迹法发现,在铁过载情况下,肝中诱导型一氧化氮合酶表达显著高于正常对照小鼠;铁过载小鼠肝中总体蛋白质硝化程度高于正常小鼠;铁过载引起的蛋白质酪氨酸硝化有一定的选择性,在铁过载小鼠肝中发现一些新的被硝化蛋白质条带(约 57 kD、 35 kD).上述结果证实,铁过载会促进肝蛋白质酪氨酸硝化.  相似文献   
5.
The aim of this study was to explore the action characters of total flavonoids from MDQ on cerebral ischemic tolerance with blood stasis. Fully understanding the mechanism of action of total flavonoids from MDQ is helpful for the development of new drugs and the utilization of resources. Male Wistar rat model of blood stasis was established by injecting dexamethasone into the intramuscular side of the thigh. Then they were given related drugs via an intragastric administration for a successive 10 days. After 7 days, the following occurred: firstly, the method of blocking the bilateral common carotid artery (CCA) was used for 10 min, followed by a restoration of perfusion. After 72 h, we performed a temporary occlusion of the rat’s middle cerebral artery for 2 h with an intraluminal thread method. This was followed by reperfusion for 24 h, respectively, to establish the rat model of cerebral ischemic tolerance with blood stasis. Viscosity of the whole blood was measured after the last administration was given blood. Brain was removed, and then the activity of ATP enzyme and T-SOD was determined. To observe the pathological changes of the hippocampus area by HE staining, and the expression of Bcl-2 and Bax were observed by immunohistochemical method. The rat model of cerebral ischemic tolerance with blood stasis was copied successfully. The whole blood viscosity, the activity of NOS, the content of Gluin in the ischemic brain in the IPC model group and the ischemia–reperfusion group were increased significantly. The activity of ATPase was decreased significantly. Compared with the ischemia–reperfusion model group, the activity of ATPase and the whole blood viscosity in the ischemic preconditioning (IPC) group were increased significantly. The activity of NOS and the content of Gluin were decreased significantly. The degree of pathological injury of the brain tissue was also relieved significantly. Total flavonoids of MDQ were used, improving blood circulation, improving energy metabolism, activating endogenous anti-oxidative capability, enhancing the antiapoptotic effect, and relieving the injury of the nerve cell. Hence, the use of MDQ flavonoids improves the tolerance ability of cerebral ischemia.  相似文献   
6.
BackgroundThe in-vitro study indicated that ERK/MAPK and PI3K/AKT signal channels may play an important role in reparative regeneration process after peripheral nerve injury. But, relevant in-vivo study was infrequent. In particular, there has been no report on simultaneous activation of ERK/MAPK and PI3K/AKT signal channels in facial nerve cell and axon after facial nerve injury.ResultsThe expression of P-ERK enhanced in nerve cells at the injury side on the 1 d after the rat facial nerve was cut and kept on a higher level until 14 d, but decreased on 28 d. The expression of P-AKT enhanced in nerve cells at the injury side on 1 d after injury, and kept on a higher level until 28 d. The expression of P-ERK enhanced at the near and far sections of the injured axon on 1 d, then increased gradually and reached the maximum on 7 d, but decreased on 14 d, until down to the level before the injury on 28 d. The expression of P-AKT obviously enhanced in the injured axon on 1 d, especially in the axon of the rear section, but decreased in the axon of the rear section on 7 d, while the expression of axon in the far section increased to the maximum and kept on till 14 d. On 28 d, the expression of P-AKT decreased in both rear and far sections of the axon.ConclusionThe facial nerve simultaneously activated ERK/MAPK and PI3K/AKT signal channels in facial nerve cells and axons after the cut injury, but the expression levels of P-ERK and P-AKT varied as the function of the time. In particular, they were quite different in axon of the far section. It has been speculated that two signal channels might have different functions after nerve injury. However, their specific regulating effects should still be testified by further studies in regenerative process of peripheral nerve injury.  相似文献   
7.
Chronic ethanol ingestion mildly damages liver through oxidative stress and lipid oxidation, which is ameliorated by dietary supplementation with the anti-inflammatory β-amino acid taurine. Kidney, like liver, expresses cytochrome P450 2E1 that catabolizes ethanol with free radical formation, and so also may be damaged by ethanol catabolism. Sudden loss of kidney function, and not liver disease itself, foreshadows mortality in patients with alcoholic hepatitis [J. Altamirano, Clin. Gastroenterol. Hepatol. 2012, 10:65]. We found that ethanol ingestion in the Lieber-deCarli rat model increased kidney lipid oxidation, 4-hydroxynonenal protein adduction, and oxidatively truncated phospholipids that attract and activate leukocytes. Chronic ethanol ingestion increased myeloperoxidase-expressing cells in kidney and induced an inflammatory cell infiltrate. Apoptotic terminal deoxynucleotidyl transferase nick-end labeling-positive cells and active caspase-3 increased in kidney after ethanol ingestion, with reduced filtration with increased circulating blood urea nitrogen (BUN) and creatinine. These events were accompanied by release of albumin, myeloperoxidase, and the acute kidney injury biomarkers kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin, and cystatin c into urine. Taurine sequesters HOCl from myeloperoxidase of activated leukocytes, and taurine supplementation reduced renal lipid oxidation, reduced leukocyte infiltration, and reduced the increase in myeloperoxidase-positive cells during ethanol feeding. Taurine supplementation also normalized circulating BUN and creatinine levels and suppressed enhanced myeloperoxidase, albumin, KIM-1, and cystatin c in urine. Thus, chronic ethanol ingestion oxidatively damages kidney lipids and proteins, damages renal function, and induces acute kidney injury through an inflammatory cell infiltrate. The anti-inflammatory nutraceutical taurine effectively interrupts this ethanol-induced inflammatory cycle in kidney.  相似文献   
8.
Acute lung injury (ALI) is a serious disease with unacceptably high mortality and morbidity rates. Up to now, no effective therapeutic strategy for ALI has been established. Rutin, quercetin-3-rhamnosyl glucoside, expresses a wide range of biological activities and pharmacological effects, such as anti-inflammatory, antihypertensive, anticarcinogenic, vasoprotective, and cardioprotective activities. Pretreatment with rutin inhibited not only histopathological changes in lung tissues but also infiltration of polymorphonuclear granulocytes into bronchoalveolar lavage fluid in lipopolysaccharide (LPS)-induced ALI. In addition, LPS-induced inflammatory responses, including increased secretion of proinflammatory cytokines and lipid peroxidation, were inhibited by rutin in a concentration-dependent manner. Furthermore, rutin suppressed phosphorylation of NF-κB and MAPK and degradation of IκB, an NF-κB inhibitor. Decreased activities of antioxidative enzymes such as superoxide dismutase, catalase, glutathione peroxidase, and heme oxygenase-1 caused by LPS were reversed by rutin. At the same time, we found that ALI amelioration by chelation of extracellular metal ions with rutin is more efficacious than with deferoxamine. These results indicate that the protective mechanism of rutin is through inhibition of MAPK–NF-κB activation and upregulation of antioxidative enzymes.  相似文献   
9.
The shoulder is inherently an unstable joint which heavily relies on the neuromuscular activation of the rotator cuff (RC) complex for stability during movement. Currently, there is no consensus regarding how the activity of RC muscles is affected among individuals with a RC tendinopathy (RCTe). This study reviewed the evidence of studies comparing the electromyographic (EMG) activity of any RC muscle of shoulders with a symptomatic RCTe to asymptomatic shoulders. Eight databases were searched. Data from 343 participants (201 symptomatic and 209 asymptomatic shoulders) were analyzed from 10 out of 402 included studies. Strong evidence for the infraspinatus and supraspinatus during isometric contractions and limited evidence for the supraspinatus and infraspinatus during isokinetic contractions suggest that the muscular activity is not altered among individuals with a RCTe during these types of contraction. Very limited evidence indicates reduced muscle activity for the infraspinatus and subscapularis in the presence of a RCTe during isotonic contractions, and no alterations for the supraspinatus or teres minor were identified. Lastly, conflicting to moderate evidence suggests alterations in RC muscle activity during unrestrained movements and swimming. These findings indicate that EMG deficits associated with a RCTe can best be appreciated during unrestrained movements.  相似文献   
10.
Abstract: Proteolytic degradation of numerous calpain substrates, including cytoskeletal and regulatory proteins, has been observed during brain ischemia and reperfusion. In addition, calpain inhibitors have been shown to decrease degradation of these proteins and decrease postischemic neuronal death. Although these observations support the inference of a role for μ-calpain in the pathophysiology of ischemic neuronal injury, the evidence is indirect. A direct indicator of μ-calpain proteolytic activity is autolysis of its 80-kDa catalytic subunit, and therefore we examined the μ-calpain catalytic subunit for evidence of autolysis during cerebral ischemia. Rabbit brain homogenates obtained after 0, 5, 10, and 20 min of cardiac arrest were electrophoresed and immunoblotted with a monoclonal antibody specific to the μ-calpain catalytic subunit. In nonischemic brain homogenates the antibody identified an 80-kDa band, which migrated identically with purified μ-calpain, and faint 78- and 76-kDa bands, which represent autolyzed forms of the 80-kDa subunit. The average density of the 80-kDa band decreased by 25 ± 4 ( p = 0.008) and 28 ± 9% ( p = 0.004) after 10 and 20 min of cardiac arrest, respectively, whereas the average density of the 78-kDa band increased by 111 ± 50% ( p = 0.02) after 20 min of cardiac arrest. No significant change in the density of the 76-kDa band was detected. These results provide direct evidence for autolysis of brain μ-calpain during cerebral ischemia. Further work is needed to characterize the extent, duration, and localization of μ-calpain activity during brain ischemia and reperfusion as well as its role in the causal pathway of postischemic neuronal injury.  相似文献   
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