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1.
Aspartame (non-nutritive sweetener) is consumed by millions of people in products like beverages, instant breakfasts, desserts, breathe mints, sugar free chewing gum, vitamins, and pharmaceutical. On a weight basis, metabolism of aspartame generates approximately 50% phenylalanine, 40% aspartic acid and 10% methanol. The detailed mechanisms of their effects on cardiac tissue are still unclear. The present study aimed to clarify whether longer time aspartame consumption has any effect on heart of Wistar albino rats. Animals were randomly divided into 4 groups of 6 animals (group-1: control, group-2: folate deficient diet fed animals, group-3: control animals treated with aspartame, group-4: folate deficient diet fed animals treated with aspartame). Aspartame was given orally (40 mg/kg·bw/day), dissolved in normal saline and for 90 days. Since human beings have very low hepatic folate content, the folate deficient diet fed animals were used to mimic the human methanol metabolism. Aspartame consumption increased significantly plasma corticosterone level, suggesting that aspartame may act as a chemical stressor. There was a significant increase in lipid peroxidation, nitric oxide and protein carbonyl, and significant decrease in protein thiol, cardiac membrane bound ATPases (Na+, K+, Ca++, Mg++), enzymatic (SOD, CAT, GPX, G6PD, GR) and non-enzymatic antioxidants (GSH, Vit-C, Vit-E) as well as a significant increase in heart rate and heart marker enzymes (CK and CK-MB). It may be due to excessive generation of free radicals, which impairs cardiac function. Aspartame metabolite methanol or formaldehyde may be the causative factors behind these changes. However, up regulation of Hsp70 in immunohistochemical analysis of cardiac tissue might be a protective response to oxidative stress induced by aspartame metabolites and structural damages in cardiac tissue.  相似文献   
2.
The present study was carried out to evaluate the potential protective role of co-administration of Ginkgo biloba, Trifolium pretenseagainst sodium arsenite-induced neurotoxicity in different parts of brain (Cerebral cortex, Hippocampus, striatum and Hind brain) and in the spinal cord of rats. Sodium arsenite caused impairment in the acquisition and learning in all the behavioral tasks and caused significant increase in tumor necrosis factor-α,thiobarbituric acid-reactive substances andlipid profile, while caused significant decrease in glutathione, total thiol content, total antioxidant capacity, acetylcholinesterase, monoamine oxidase and ATPases activities. These results were confirmed by histopathological, fluorescence and scanning electron microscopy examination of different regions of brain. From these results sodium arsenite-induced neurodegenerative disorder in different regions of brain and spinal cord and this could be mediated through modifying the intracellular brain ions homeostasis, cholinergic dysfunction and oxidative damage. The presence of Ginkgo biloba and/orTrifolium pretense with sodium arsenite minimized its neurological damages. It was pronounced that using Ginkgo biloba and Trifolium pretense in combination was more effective as protective agents compared to use eachone of them alone.  相似文献   
3.
The present study is aimed at evaluating the protective role of l-theanine on aroclor 1254-induced oxidative stress in rat brain. Intraperitoneal administration of Aroclor 1254 (2 mg/kg b.wt. for 30 days) caused oxidative stress in rat brain and also caused neurobehavioral changes. Oxidative stress was assessed by determining the levels of lipid peroxide (LPO), protein carbonyl content, and changes in activities of creatine kinase (CK), acetylcholinesterase (AchE), and ATPases in the hippocampus, cerebellum and cerebral cortex of control and experimental rats. Histopathological results showed that PCB caused neuronal loss in all three regions. PCB upregulated the mRNA expressions of inflammatory cytokines. Oral administration of l-theanine (200 mg/kg b.wt.) increased the status of antioxidants, decreased the levels of LPO, nitric oxide (NO) and increased the activities of CK, AchE and ATPases. l-Theanine restored normal architecture of brain regions and downregulated the expression of inflammatory cytokines. In conclusion, l-theanine shows a protective role against PCBs-induced oxidative damage in rat brain.  相似文献   
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5.
The role of the kidney in combating metabolic acidosis has been a subject of considerable interest for many years. The present study was aimed to determine whether there is an altered regulation of renal acid base transporters in acute and chronic acid loading. Male Sprague-Dawley rats were used. Metabolic acidosis was induced by administration of NH(4)Cl for 2 days (acute) and for 7days (chronic). The serum and urinary pH and bicarbonate were measured. The protein expression of renal acid base transporters [type 3 Na(+)/H(+) exchanger (NHE3), type 1 Na(+)/HCO(3) (-) cotransporter (NBC1), Na-K(+) ATPase, H(+)-ATPase, anion exchanger-1 (AE-1)] was measured by semiquantitative immunoblotting. Serum bicarbonate and pH were decreased in acute acid loading rats compared with controls. Accordingly, urinary pH decreased. The protein expression of NHE3, H(+)-ATPase, AE-1 and NBC1 was not changed. In chronic acid loading rats, serum bicarbonate and pH were not changed, while urinary pH was decreased compared with controls. The protein expression of NHE3, H(+)-ATPase was increased in the renal cortex of chronic acid loading rats. These results suggest that unaltered expression of acid transporters combined with acute acid loading may contribute to the development of acidosis. The subsequent increased expression of NHE3, H(+)-ATPase in the kidney may play a role in promoting acid excretion in the later stage of acid loading, which counteract the development of metabolic acidosis.  相似文献   
6.
Objective Chronic myocardial ischemia (CMI) has become the most importat cause of heart failure (HF) all over the world. The aim of the current study was to investigate the effects of Sarcoendoplasmic reticulum calcium ATPaee 2a (SERCA2a) gene transfer on cardiac function and endoplasmic reticulum stress (ERS) associated myocardial apoptosis in a minipig HF animal model induced by CMI. Methods HF was induced in minipigs by implantation of ameroid constrictor in the initial segment of left anterior descending (LAD) branch of coronary artery. After confirmation of myocardial perfusion defects and cardiac function impairment by myocardial perfusion imaging and echocardiography, animals were divided into 4 groups (n =4 each): HF group, HF + enhanced green fluorescent protein (EGFP) group,HF + SERCA2a group, and shamed animals as control group. A total amount of 1×1012 v.g. Of rAAV1EGFP or rAAV1-SERCA2a were injected intramyocardially to each animal of HF + EGFP and HF +SERCA2a groups. Sixty days after gene transfer, protein level and activity of SERCA2a were examined,cardiac functions and changes of serum inflammatory and neuro-hormonal factors were determined. Apoptotic index of the ischemic myocardium, protein levels of ER stress marker glucose regulated protein 78 ( GRP 78) and ER stress specific apoptotic marker caspase-12 were also assayed. Results At the study end,echocardiographic and hemodynamic measurements indicated a significant improvement of both cardiac systolic and diastolic function in HF + SERCA2a group compared with HF/HF + EGFP groups [LVEF (60.2±8.6)%vs (44.2±7.1)% and (46.8±6.7)%, Ev/Ay 1.28±0.24 vs 0.77 ±0.17 and 0.80±0.21, +dp/dtmax(2713.9 ±434.0) mm Hg/s ( 1 mm Hg =0.133 kPa) vs (1892.3 ±434.2) mm Hg/s and (1931.2±397.4)mm Hg/s, -dp/dtmax (1422.1±334.4) mm Hg/s vs (848.3±308.3) mm Hg/s and (849.5±278.3)mm Hg/s, P<0.05], along with increase in both SERCA2a protein level (1.13±0.26 vs 0.73 ±0.17 and 0.64±0.18, P<0.05) and activity [(16.2±5.5) IU/ml vs (7.9±3.1) IU/ml and (7.5 ±2.8)IU/ml, P <0.05] compared with HF/HF + EGFP groups. Serum concentrations of inflammatory factor tumor necrotic factor α [(382.3±114.4) ng/L vs (732.3±201.4) ng/L and (689.8±192 5) ng/L, P<0. 05], neural-hormonal factors brain natriuretic peptide [(142.6±45.3) ng/L vs (422.3±113.6) ng/L and(393.7 ±103.3)ng/L, P<0.01], endothelin-1 [(111.4 ±37.5)ng/L vs (193.5 ±54.3)ng/L and (201.0±72.1)ng/L,P<0.05] and angiotensin Ⅱ[(189.7±65.2)μg/L vs (538.3 ± 135.2) μg/L and ( 525.5±144.1)μg/L, P<0.01] were also significantly decreased in HF + SERCA2a group compared with HF/HF + EGFP groups. The apoptotic index [(12.71±4.11)% vs(23.22±7.23) % and (24.31±6.38)%, P<0.05], protein levels of GRP78 (1.27±0.33 vs 3.23±1.14 and 4.18±1.13, P<0.05)and protein level ratios of cleaved caspase-12 to total caspase-12[(4.62±1.93)% vs (9.71±2.70)% and (10.14±2.81)%, P<0.05] were also significantly reduced in the ischemic myocardium of HF+SERCA2a group compared with the HF/HF + EGFP groups. Conclusion Overexpression of SERCA2a significantly improved cardiac systolic and diastolic function in this HF model partly through attenuation of ER stress related myocardial apoptosis, suggesting its therapeutic potential for CM1 related heart failure.  相似文献   
7.
目的建立大鼠急性心肌梗死模型,观察心肌梗死后心室重塑过程中肌浆网钙转运ATP酶(Ca-2+ATPase,SERCA)和受磷蛋白(PLB)的表达变化。方法雄性SD大鼠,应用前降支动脉结扎法建立大鼠心肌梗死模型,术后4周观察血流动力学参数,SERCA mRNA和PLB mRNA的表达。结果大鼠心肌梗死后4周,心肌梗死组左心室舒张末压(LVEDP)显著大于假手术组,左心室内压最大上升和下降速率(±dp/dtmax)显著低于假手术组。心肌梗死组心肌组织中SERCA mRNA表达下调,PLB mRNA表达上调。结论大鼠心肌梗死4周后心室收缩和舒张功能已降低,进入了心力衰竭阶段,SERCA mRNA和PLB mRNA的表达变化与心力衰竭的发生发展相关,可能是心肌梗死后心肌收缩和舒张功能失调的重要机制。  相似文献   
8.
Tuberculosis (TB) is one of the most important public health problems around the world. The emergence of multi‐drug‐resistant (MDR) and extensively drug‐resistant (XDR) Mycobacterium tuberculosis strains has driven the finding of alternative anti‐TB targets. In this context, P‐type ATPases are interesting therapeutic targets due to their key role in ion homeostasis across the plasma membrane and the mycobacterial survival inside macrophages. In this review, in silico and experimental strategies used for the rational design of new anti‐TB drugs are presented; in addition, the chemical space distribution based on the structure and molecular properties of compounds with anti‐TB and anti‐P‐type ATPase activity is discussed. The chemical space distribution compared to public compound libraries demonstrates that natural product libraries are a source of novel chemical scaffolds with potential anti‐P‐type ATPase activity. Furthermore, compounds that experimentally display anti‐P‐type ATPase activity belong to a chemical space of molecular properties comparable to that occupied by those approved for oral use, suggesting that these kinds of molecules have a good pharmacokinetic profile (drug‐like) for evaluation as potential anti‐TB drugs.  相似文献   
9.
目的:探讨质膜 Ca2+-ATP 酶异构体2(PMCA2)基因的多态性与突发性耳聋的关系。方法采用分组研究的方法,对164名受检者进行调查和听力测试,按听力学评价的结果将其分为感音神经性听力损失的突发性耳聋组(n=82)和听力正常组(n=82);用 PCR 和等位基因特意扩增法检测 PMCA2基因上 rs2289274和 rs6790640两个单核苷酸位点的多态性。结果在突发性耳聋组中,rs2289274位点基因型频率分别为 AA 55.8%,AG 17.4%,GG 26.8%,等位基因频率 A 64.5%和 G 35.5%。在听力正常组中,rs2289274位点基因型频率分别为 AA 26.8%,AG 28.0%,GG 45.2%,等位基因频率 A 41.1%和 G 58.9%。在突发性耳聋组中,rs6790640位点基因型频率分别为 CC 18.3%,CT 35.4%,TT 46.3%,等位基因频率 C 36.3%和 T 63.7%。在听力正常患者组中,rs6790640位点基因型频率分别为 CC 2.4%,CT 63.4%,TT 34.1%,等位基因频率 C 34.1%和 G 65.9%。两位点的基因型分布及其等位基因频率在突发性耳聋组和听力正常患者组之间部分差异有统计学意义(P<0.05)。结论 PMCA2基因 rs2289274和 rs6790640两个单核苷酸位点的多态性可能是突发性耳聋的遗传易感性因素。  相似文献   
10.
目的:探讨柔红霉素( DNR)致大鼠心肌损伤的作用机制。方法用随机数字表法将健康清洁的SD大鼠分为DNR组和对照组,每组20只。DNR组腹腔注射DNR 3.5 mg/kg,对照组腹腔注射等容积0.9%氯化钠注射液,均每周1次,连续4周。注射DNR或0.9%氯化钠注射液1、3和4周末2组分别各取5只大鼠进行心电图、心肌组织肌浆网Ca^2﹢-ATP酶( SERCA2a)蛋白表达及组织病理学检测。结果腹腔注射DNR可成功复制亚急性心肌损伤大鼠模型。实验第2周时DNR组大鼠出现精神差、活动缓慢、嗜睡、进食减少等症状,对照组大鼠活动、体重、进食均正常;第4周大鼠心电图QRS波电压下降>30%,ST段抬高,P波尖耸,心肌组织病理学检查显示心肌细胞胞质浑浊,有空泡形成,肌纤维排列紊乱,间隔增宽。实验1周时2组大鼠心肌组织SERCA2a蛋白表达均呈中等阳性,而实验3及4周末DNR组大鼠心肌组织SERCA2a蛋白表达均呈弱阳性。实验3及4周末,DNR组大鼠SERCA2a蛋白表达阳性细胞数明显低于同时点对照组大鼠[(42.2±1.2)个比(65.30±1.6)个,(35.2±6.0)个比(66.7±1.5)个,均P﹤0.05]。结论 DNR可抑制大鼠心肌组织SERCA2a蛋白表达,可能是其心肌毒性的机制之一。  相似文献   
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