Lipid peroxidation and antioxidant status in blood of rheumatoid arthritis patients

The main objective of the study was to assess the oxidative stress in plasma and erythrocytes of rheumatoid arthritis patients by measuring the levels of thiobarbituric acid reactive substances (TBARS), non-enzymatic antioxidants (vitamin E, C and reduced glutathione) and enzymatic antioxidants [superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSHPx)]. This study has been conducted on twenty-two adult female rheumatoid arthritis patients and an equal number of healthy subjects. Elevated lipid peroxidation and multidirectional changes in the antioxidant defence system were noticed in patients with rheumatoid arthritis. The enhanced lipid peroxidation accompanied by disturbance in antioxidant status indicates that rheumatoid arthritis patients are more prone to free radical mediated oxidative damage.     

Antihyperglycemic and antilipidperoxidative effects of<Emphasis Type="Italic">Tephrosia purpurea</Emphasis> seed extract in streptozotocin induced diabetic rats

The aim of the present study was to evaluate the antihyperglycemic and antilipidperoxidative effects of ethanolic seed extract ofTephrosia purpurea (TpEt) in streptozotocin induced diabetic rats. Hyperglycemia associated with an altered hexokinase and glucose 6 phosphatase activities, elevated lipid peroxidation, disturbed enzymatic and non-enzymatic antioxidants status were observed in streptozotocin induced diabetic rats. Oral administration of “TpEt” at a dose of 300mg/kg bw showed significant antihyperglcemic and antilipidperoxidative effects as well as increased the activities of enzymatic antioxidants and levels of non enzymatic antioxidants. We also noticed that the antihyperglycemic effect of plant drug (TpEt) was comparable to that of the reference drug glibenclamide. Our results clearly indicate that “TpEt” has potent antihyperglycemic and antilipidperoxidative effects in streptozotocin induced diabetic rats and therefore further studies are warranted to isolate and characterize the bioactive antidiabetic principles from “TpEt”.     

脂筏与细胞信号转导

论述了脂筏的组成、结构与功能,脂筏在细胞信号转导正负调控、T细胞的信号转导、精子膜的信号转导过程中的作用及其机制.小窝蛋白及其参与的信号转导过程与葡萄糖运输、糖尿病及其并发症有密切关系.     

藜蒿绿原酸的提取及抗脂质过氧化作用研究

目的研究藜蒿绿原酸的提取工艺、含量和抗脂质过氧化作用.方法采用超声波辅助甲畔浸提法提取藜蒿绿原酸,紫外分光光度法测其含量,通过正交试验探索绿原酸的最佳提取工艺;以硫代巴比妥钠法研究绿原酸抗脂质过氧化作用.结果在最佳提取工艺(甲醇浓度75%、料液比1∶25、温度70℃、pH 3.0)下藜篙绿原酸的含量为0.98%;在0....     

Effect of supplementation of vitamin C and E on oxidative stress in osteoporosis

Osteoporosis encompasses a wide spectrum of conditions associated with imbalance of osteoclastic and osteoblastic activities. The increased activity of osteoclasts leads to increased free radical formation and hence lipid peroxidation. Present study probes into the role of antioxidants as a palliative treatment for osteoporosis. It involved 50 healthy controls and 75 clinically diagnosed osteoporosis patients. Both the groups underwent baseline assessment of biochemical markers viz. osteoblastic markers: serum Alkaline phosphatase. Free or ionic calcium and Inorganic phosphorus, osteoclastic markers: serum Tartarate resistant acid phosphatase and Malondialdehyde and the antioxidant status: serum Superoxide dismutase and Erythrocyte reduced glutathione. The osteoporotic group was then divided into groups A (Vitamin E-Evinal 400 mg), B (Vitamin C-Celin 500 mg), C (Vitamin E+C-Evinal+Celin) for antioxidant supplementation for a period of 90 days. The results reveal that there is significant fall in concentration of serum MDA (p<0.001), TrACP (p<0.01). Improvement in antioxidant status is reflected by significant rise in concentration of serum SOD (p<0.001) and erythrocyte GSH (p<0.001) after 90 days of antioxidant supplementation in osteoporosis. The findings indicate that on the whole bone status improved with prolonged antioxidant vitamin supplementation, which can be used as a palliative treatment for osteoporosis. The efficacy is not affected whether the vitamins are administered singly or conjointly.     

Hypoglycaemic, hypolipidemic and antioxidant properties of tulsi (Ocimum sanctum linn) on streptozotocin induced diabetes in rats

Effect of oral administration of 200 mg/Kg body weight of the aqueous extract ofOcimum sanctum (Tulsi) mixed with diet for eight weeks to diabetic (streptozotocin induced) rats was studied. There was significant reduction in fasting blood glucose, serum lipid profile, lipid peroxidation products, (LPO) and improvement in glucose tolerance. The aqueous extract also decreased LPO formation (thiobarbituric acid reactive substances TBARS) and increased antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione transferase (GT) and one antioxidant reduced glutathione (GSH) in plasma and rat liver, lung, kidney and brain. The decrease in TBARS and increase in GSH, SOD, CAT, GPX, and GT clearly shows the antioxidant property ofOcimum sanctum.     

Evaluation of adenosine deaminase activity and lipid peroxidation levels in diabetes mellitus

There was increase in erythrocyte lipid peroxidation and adenosine deaminase (ADA) activity in red blood cells (RBC's), white blood cells (WBC's) and plasma, in 30 patients of confirmed diabetes mellitus, 10 each of insulin dependent diabetes mellitus (IDDM or type I), non-insulin dependent diabetes mellitus (NIDDM or type II) and diabetes with ketoacidosis when compared with 20 healthy individuals (controls). Glycosylated hemoglobin A1c%, plasma free fatty acid (FFA) and glycerol levels were also elevated in all the cases when compared with controls. The increase was more in diabetic ketoacidosis group. Significant positive correlations were seen between erythrocyte lipid peroxidation and ADA activities in RBC's, WBC's and plasma. It is suggested that decreased tissue adenosine levels due to increase in ADA activity, is related to the severity of hyperglycemia and lipid peroxidation in diabetes mellitus.     

不同脱水方法对苦瓜种子活力影响的研究

成熟的苦瓜种子含水量较高，对脱水的反应既有别于正常性种子，又不同于顽拗性种子．室温下应用不同的方法脱水，虽然脱水速度不同，但都有利于苦瓜种于萌发．当含水量在6％以上时．随含水量降低，种子发芽率，发芽势和活力指数显著提高；超氧物歧化酶（SOD）的活性略有降低，脂氧合酶（LOX）的活性和丙二醛（MDA）含量缓慢上升．当含水量低于6％时，种子发芽率和活力指数下降．SOD活性迅速降低，LOX活性和MDA含量明显增加．温度较高的日晒脱水可显著降低苦瓜种子的发芽率和活力指数．使种子很快死亡；并显著降低SOD和LOX的活性．MDA含量增加明显．室温脱水和6％～9％的含水量有利于苦瓜种子的萌发和活力保持．     

补充抗氧化剂对老年运动小鼠脂质过氧化的保护作用

为了研究抗氧化剂（维生素Ｅ、维生素Ｃ和硒）对老年运动小鼠抗氧化能力的影响,给老年运动小鼠初充抗氧化剂（每５ｍｌ钦用水中含ＶｉｔＥ０．２５ＩＵ,ｖＩＴＣ０．５ｍｇ,亚硒酸钠０．００５ｍｇ）,时间长达５个月,测定小鼠肝脏胞浆,线粒体抗氧化酶生,结果发现,补充抗氧化剂可显提高运动小鼠肝脏ＣｕＺｎＳＯＤ及胞浆ＧＳＨ－ｐｘ活性,而对肝脏ＭｎＳＯＤ、线粒体ＧＳＨ－ｐｘ及胞浆Ｃａｔ活性影响不明显,补充抗氧化剂     

Total antioxidant capacity and lipid peroxidation in liver transplantation

Liver transplantation is an accepted therapy for chronic liver disease patients. These patients generally have low levels of fat soluble vitamins, which have important antioxidant roles. Therefore, this study was undertaken to investigate whether such patients had evidence of antioxidant depletion and increased lipid peroxidation before transplant and whether the subsequent ischemia and reperfusion encountered during liver transplantation have any effect on antioxidant levels and lipid peroxidation. We assessed plasma total antioxidant capacity and serum lipid peroxide in 12 patients undergoing liver transplantation and equal numbers of healthy subjects. We found that before reperfusion, antioxidant levels were significantly decreased along with significantly elevated lipid peroxidation levels as compared with healthy controls (P<0.001). On reperfusion of the liver graft, further declined values of total antioxidant accompanied with highly elevated lipid peroxidation were seen than those of pre-reperfusion samples (P<0.001). This data shows that patients undergoing liver transplant have lowered antioxidant defenses and evidence of free radical damage, which compound the additional insult of reperfusion injury. Therefore antioxidant therapy in these patients before transplantation may ameliorate the effects of reperfusion.