Search

Start Over Creator O.

2. Energy Metabolism of Adipose Tissue – Physiological Aspects and Target in Obesity Treatment

Creator:
Kopecký, J., Rossmeisl, M., Flachs, P., Brauner, P., Šponarová, J., O., Pražák, T., Růžičková, J., Bardová, k., and Kuda, O.
Type:
article, model:article, and TEXT
Subject:
Uncoupling protein, Adipose tissue, Lipogenesis, Lipolysis, and Obesity
Language:
English
Description:
Body fat content is controlled, at least in part, by energy charge of adipocytes. In vitro studies indicated that lipogenesis as well as lipolysis depend on cellular ATP levels. Respiratory uncoupling may, through the depression of ATP synthesis, control lipid metabolism of adipose cells. Expression of some uncoupling proteins (UCP2 and UCP5) as well as other protonophoric transporters can be detected in the adipose tissue. Expression of other UCPs (UCP1 and UCP3) can be induced by pharmacological treat ments that reduce adiposity. A negative correlation between the accumulation of fat and the expression of UCP2 in adipocytes was also found. Ectopic expression of UCP1 in the white fat of aP2-Ucp1 transgenic mice mitigated obesity induced by genetic or dietary factors. In these mice, changes in lipid metabolism of adipocytes were associated with the depression of intracellular energy charge. Recent data show that AMP-activated protein kinase may be involved in the complex changes elicited by respiratory uncoupling in adipocytes. Changes in energy metabolism of adipose tissue may mediate effects of treatments directed against adiposity, dyslipidemia, and insulin resistance.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Folate Co-Administration Improves the Effectiveness of Fenofibrate to Decrease the Lipoprotein Oxidation and Endothelial Dysfunction Surrogates

Creator:
O., J., Šimon, Holubec, L., Pikner, R., and Trefil, L.
Type:
article, model:article, and TEXT
Subject:
Fenofibrate, Homocysteine, Folate, Lipoprotein exidation, and Endothelial dysfunction
Language:
English
Description:
Fibrate therapy results in elevation of plasma total homocysteine (tHcy), which is known to induce oxidative stress and endothelial dysfunction. We aimed to establish whether fibrate-induced elevation of tHcy has also similar consequences and whether they may be prevented by folate co-administration. Eighteen subjects with hypercholesterolemia were included in an open, prospective, cross-over study. We compared intra-individually the effect of fenofibrate on tHcy, oxidative stress and endothelial dysfunction surrogates, in monotherapy and when combined with 10 mg of folate. These effects were also compared with fluvastatin monotherapy. Fenofibrate in monotherapy significantly decreased LDL cholesterol, increased the tHcy by 39.5 %, while oxidized LDL (oxLDL), malondialdehyde (MDA), von Willebrand factors (vWf) and thrombomodulin (TMD) remained unchanged. When fibrate was co-administered with folate, the tHcy remained on the initial post-diet level, while both the total and oxLDL as well as MDA, vWf and TMD decreased. In contrast to fenofibrate monotherapy, fluvastatin (80 mg) had a similar effect as combined therapy with fenofibrate and folate, while tHcy remained uninfluenced. In conclusion, fenofibrate decreases the LDL cholesterol, but in contrast to fluvastatin, has no significant antioxidative and endothelium-protective potential, probably due to a concomitant increase of tHcy. These effects may be improved by co-administration of folate.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. Rooibos Tea (Aspalathus linearis) Partially Prevents Oxidative Stress in Streptozotocin-Induced Diabetic Rats

Creator:
O., Vančová, O., Božek, P., Čársky, J., Šebeková, K., Boor, P., Nakano, M., and Greksák, M.
Type:
article, model:article, and TEXT
Subject:
Rooibos tea, Aspalathus linearis, Oxidative stress, and Streptozotocin-induced diabetes
Language:
English
Description:
The aim of this study was to investigate the effects of rooibos tea as a natural source of a wide scale of antioxidants on the prevention and treatment of oxidative stress in streptozotocin-induced diabetic rats. Expected significant changes of biochemical parameters characteristic for experimental diabetic state were found in plasma and tissues eight weeks after single dose streptozotocin application. Administration of aqueous and alkaline extracts of rooibos tea (or N-acetyl-L-cysteine for comparison) to diabetic rats did not affect markers of the diabetic status (glucose, glycated hemoglobin and fructosamine). Besides the parameters characterizing hepatotoxic effect of streptozotocin, rooibos tea significantly lowered advanced glycation end-products (AGEs) and malondialdehyde (MDA) in the plasma and in different tissues of diabetic rats, particularly MDA concentration in the lens. From these results we can conclude that antioxidant compounds in rooibos tea partially prevent oxidative stress and they are effective in both hydrophobic and hydrophilic biological systems. Therefore, rooibos tea as a commonly used beverage can be recommended as an excellent adjuvant support for the prevention and therapy of diabetic vascular complications, particularly for protecting ocular membrane systems against their peroxidation by reactive oxygen species.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public