THE TRANSPORT OF VITAMIN-E IN PLASMA AND ITS CORRELATION TO PLASMA-LIPOPROTEINS IN NON-INSULIN-DEPENDENT DIABETES-MELLITUS

It is known that plasma low density lipoproteins (LDL) contain a great amount of vitamin E and that LDL enter cells via the specific receptor-mediated mechanism. In this study, we aimed to investigate the transport of alpha-tocopherol from plasma to tissues in subjects with non-insulin-dependent diabetes mellitus (NIDDM) with poor glycaemic control; and the relationships between alpha-tocopherol and plasma lipid and lipoprotein levels. alpha-Tocopherol determination was carried out by colorimetric assay according to the modified micromethod of Fabianek et al. The mean plasma alpha-tocopherol and (LDL + VLDL)-alpha-tocopherol levels increased significantly in the diabetic group as compared to control (P < 0.05 and P < 0.02), whereas the high density lipoprotein (HDL)-alpha-tocopherol level was significantly lower in the diabetic group than that in the controls (P < 0.05). Correlations between plasma alpha-tocopherol levels showed close positive relationships (r = 0.87, r = 0.75 and r = 0.78, respectively, P < 0.001). A strong positive correlation was also observed between alpha-tocopherol and the cholesterol content, either in the HDL or in the (LDL + VLDL) fractions (r = 0.75 and r = 0.77; P < 0.001). These findings indicate that there is a direct positive relationship between lipid and alpha-tocopherol concentrations. The increased level of alpha-tocopherol in the LDL + VLDL fraction and decreased level in HDL in these patients could be attributed to the impairment of the cholesterol uptake of the cells by the receptor mediated mechanism

Alterations in superoxide dismutase activities, lipid peroxidation and glutathione levels in thinner inhaled rat lungs: Relationship between histopathological properties

Paint thinner has widespread use in industry. The use of thinner among children as a narcotic agent has become a social and health problem. There is some evidence that organic solvents may express their toxicity by the way of reactive oxygen species (ROS) induced cell damage. ROS has been shown to induce lipid peroxidation in biological membranes. This study examined peroxidative and histopathological changes in the rat lung, during 5 weeks of thinner inhalation. Significant increases were found in lipid peroxidation (MDA + 4-DHA) levels related to the duration of inhalation. As opposed to increases in the lipid peroxidation levels, significant decreases in superoxide dismutase activities and glutathione levels were observed from the third inhalation week to the end of the fifth week. At the beginning of the inhalation slight inflammatory changes, intraalveolar and interstitial extravasation and oedema in lung parenchyma were noted. As the inhalation period extended, chronic inflammatory changes, alveolar epithelial proliferation, collapse, emphysematous changes and interstitial fibrosis in lung were detected. (C) 1998 The Italian Pharmacological Society

FIBRONECTIN AND SIALIC-ACID LEVELS IN HUMAN MENINGIOMAS AND GLIOMAS

In this study, fibronectin and sialic acid levels have been assayed in human meningiomas and gliomas. The mean fibronectin and sialic acid levels for human meningiomas were 22.01 +/- 9.70 mu g/mg protein and 19.58 +/- 4.89 mu g/mg protein, respectively, and for human gliomas were 27.30 +/- 13.70 mu g/mg protein and 25.67 +/- 11.60 mu g/mg protein, respectively, versus 9.23 +/- 5.40 mu g/mg protein and 13.50 +/- 4.30 mu g/mg protein for normal brain tissues. Fibronectin and sialic acid levels were significantly higher in human meningiomas (P < 0.01 and P < 0.05) and gliomas (P < 0.001 and P < 0.01) than control group. Also the mean fibronectin and sialic acid levels were found to be 18.27 +/- 7.08 mu g/mg protein and 17.04 +/- 6.25 mu g/mg protein in Grade I-II and 32.60 +/- 15.00 mu g/mg protein ad 29.50 +/- 11.60 mu g/mg protein in Grade III-IV gliomas, respectively. Fibronectin and sialic acid levels were significantly higher in Grade III-IV gliomas than Grade I-II gliomas (P < 0.05)

TISSUE LIPID-COMPOSITION OF HUMAN GLIOMAS AND MENINGIOMAS

This study is a comparative analysis of some lipid fractions in human brain tumors and normal brain tissue. Gliomas and meningiomas were studied and in these tumors while total lipid, total and free cholesterol and total phosphoglyceride levels were found to be significantly lower than in normal controls, the difference in esterified cholesterol levels was found to be insignificant. No significant differences in lipid fractions existed between gliomas and meningiomas except total and esterified cholesterol values

Alterations in lipid peroxidation and antioxidant status in different types of intracranial tumors within their relative peritumoral tissues

Objectives: Elevated levels of lipid peroxidation and changes in the concentration of enzymatic and nonenzymatic antioxidant systems have been reported in various cancers, but there are very few reports available of lipid peroxidation due to oxidative stress in patients with intracranial neoplasms. The purpose of this study was to assess alterations in lipid peroxidation and antioxidant status in different types of tumors and to compare the results with their relative peritumoral tissues and compare the oxidative status in different grades of tumors

Carbohydrate-deficient transferrin and sialidase levels in coronary heart disease

Transferrin is a N-glycosylated glycoprotein and plays an important role in iron transport from sites of absorption and storage to sites of utilization. The main component of normal serum transferrin contains two biantennary glycans, each consisting of 2 mol of sialic acid (Tetrasialo transferrin). Normal serum also contains small amounts of tri- and disialotransferrin, We have undertaken this study to investigate the levels of serum carbohydrate-deficient transferrin (Desialotransferrin) and sialidase levels in patients with coronary heart disease. In patient group, serum desialotransferrin and sialidase levels were found to be significantly higher than control group (p < 0.01 and p < 0.001, respectively), We conclude that increased activity of sialidase may be responsible for increased desialotransferrin in patients with coronary heart disease. Serum desialotransferrin levels map be useful critaria to diagnosis and pathogenesis of coronary heart disease. (C) 2000 Elsevier Science Ltd. All rights reserved

The relationship of various factors in the pathogenesis of atherosclerosis

In this study we investigated the levels of lipid parameters, fibronectin, tissue-type plasminogen activator and plasminogen activator inhibitor (t-PA-PAI-1) complex and sialidase in patients with coronary heart disease and a control group. Total cholesterol, triglyceride, low-density lipoprotein (LDL). and very-low-density lipoprotein (VLDL) cholesterol and lipoprotein Lp(a), levels in patients with coronary heart disease were found to be significantly higher than in the control group (p <.001). High-density lipoprotein (HDL) cholesterol levels in patient group were significantly lower than control group (p <.001). Plasma fibronectin and t-PA-PAI-1 complex levels in patients with coronary heart disease were found to be significantly higher than control group (p <.05 and p <.001, respectively). In addition, we found that serum sialidase levels in patients with coronary heart disease were significantly higher than in the control group (p <.001). The electrophoretic mobility of lipoproteins from patients with coronary heart disease was found to be greater than those from the control group. As a result Lp(a) may play an important role in the pathogenesis of atherosclerosis by causing foam cell formation because of interacting with LDL or fibronectin and by interfering with the fibrinolytic system because of binding to plasminogen receptors. In addition, modifications of Lp(a) (including desialylation) may effect these events

Tissue sialic acid and fibronectin levels in human prostatic cancer

We investigated the tissue concentration of sialic acid and fibronectin in patients with prostatic cancer. The mean sialic acid and fibronectin levels in patients with prostatic cancer were 19.02 +/- 6.30 mu g/mg protein and 20.22 +/- 7.13 mu g/mg protein, respectively versus 13.01 +/- 4.53 mu g/mg protein and 11.77 +/- 6.74 mu g/mg protein for normal prostatic tissues. Sialic acid and fibronectin levels in cancerous patients were significantly higher than in the control group (P < 0.05)

Tissue and serum sialidase levels in breast cancer

Breast cancer is both one of the most common and one of the most treatable of all human malignancies. It has been suggested by various investigators that sialic acid increases in the sera of cancerous patients. In cancer patients, an increase in the levels of serum sialic acid may also be due to an increase in the activity of serum or tissue sialidase, The purpose of the present investigation was to determine whether the concentration of sialidase in serum and breast tissue could be used as a tumor marker in breast cancer. In this study; serum sialidase levels in 26 patient with breast cancer and 31 controls were found to be 77.04 +/- 25.07 U/l and 55.56 +/- 7.50 U/l, respectively. The mean tissue sialidase levels in 26 breast cancer patients and 13 controls were 39.76 +/- 17.03 U/g protein acid 14.30 +/- 7.09 U/g protein, respectively. Serum and tissue sialidase levels in breast cancer were significantly higher than those found in the control group (P < 0.001). The mean serum and tissue sialidase levels in 14 Grade I-II and 12 Grade III breast cancer patients were found to be 67.73 +/- 11.87 U/l and 33.41 +/- 12.17 U/g protein and 87.89 +/- 31.94 U/l and 47.17 +/- 19.30 U/g protein, respectively. Also we found a significant difference between the levels of serum and tissue sialidase in Grade I-II and III (P < 0.05), (C) 1999 Elsevier Science Ireland Ltd. All rights reserved

Increased serum sialic acid levels in primary Osteoarthritis and inactive rheumatoid arthritis

ALTURFAN, A.A., USLU, E., ALTURFAN, E.E., HATEMI, G., FRESKO, I. and KOKOGLU, E. Increased Serum Sialic Acid Levels in Primary Osteoarthritis and Inactive Rheumatoid Arthritis. Tohoku J. Exp. Med., 2007, 213 (3), 241-248 - Accumulation of oxidized proteins and impaired antioxidant system have been shown to be associated with arthritis. Serum sialic acid (SA) is known as a parameter of inflammation. In the present study, to explore the potential role of SA in arthritis, we measured serum SA levels, plasma protein oxidation, and antioxidant status in patients with primary osteoarthritis (POA) and inactive rheumatoid arthritis (RA). Inactive RA (iRA) was defined upon the American College of Rheumatology criteria for clinical remission of RA. A total of 40 patients (20 POA patients, including 4 male subjects, and 20 iRA female patients) and 20 healthy female subjects were included in this study. SA, antioxidants, and protein oxidation levels were determined spectrophotometrically in serum or plasma samples. Serum SA levels were significantly increased in POA (3.34 +/- 0.37 mM, p < 0.0001) and 1RA (3.11 +/- 0.47 mM, p < 0.05), compared with healthy controls (2.41 +/- 0.16 mM). Plasma total antioxidant activity, plasma superoxide dismutase activity and serum reduced glutathione levels were significantly decreased in patients with POA and those with iRA, whereas plasma carbonyl content and serum total protein were increased in those patients. Moreover, plasma total thiol levels were significantly increased in iRA and decreased in POA. Thus, increased SA and protein oxidation levels are associated with the decreased antioxidant levels in POA and iRA patients. These results suggest that SA may be considered as a potent defense molecule against oxidative damage in arthritis. Antioxidant therapy may halt or ameliorate the progression of arthritis. - osteoarthritis; rheumatoid arthritis; oxidative stress; antioxidants; sialic acid (c) 2007 Tohoku University Medical Press