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Although, several health benefits were associated with green tea, these effects may be beneficial up to a certain dose. Higher doses of green tea may cause several adverse effects. So, there is a need to test the potential negative effects of green tea during pregnancy. This study was designated to evaluate the effect of prenatal exposure of green tea extract on the development of the central nervous system of 20-day old rat fetuses. The pregnant rats were divided into 4 groups; the control group (received distal water) and the other 3 groups received green tea extract at different doses (200, 600 & 1000 mg/kg/day, respectively) from the 6th to 15th day of gestation i.e., during the organogenesis phase of development. Cerebral cortex, cerebellum and spinal cord specimens were subjected to histological, immunohistochemical and ultrastructure investigations. The body weight of both mothers and fetuses was significantly decreased in the groups that received 600 and 1000 mg green tea extract. Also, the neuronal tissues displayed various signs of degeneration which were evident with the 600 and 1000 mg doses. Green tea extract also increases the glial fibrillary acidic protein (GFAP) and decreases the proliferating cell nuclear antigen (PCNA) which were directly proportional with increasing the dose. Administration of green tea extract during rat organogenesis period induced various histological, immunohistochemical and ultrastructural degenerative changes in the cerebral cortex, cerebellum and spinal cord of 20-day old rat fetuses. These deleterious changes were directly proportional to increasing the green tea extract dose. Thus, it should be stressed that the effect of green tea is dose-dependent and therefore it can be either beneficial or adverse. 相似文献
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Elhendawy Mohammed Abdul-Baki Enas A. Abd-Elsalam Sherief Hagras Maha M. Zidan Abdul-Aziz Abdel-Naby Amira Y. Watany Mona Elkabash Ibrahem Ali Salem Mohamed Labib Elshanshoury Mohamed Soliman Shaimaa Abdou Said 《Molecular biology reports》2020,47(7):4955-4955
Molecular Biology Reports - The correct spelling of the 7th authors' name is Mona Watany. 相似文献
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Radioactive 1-Azidonaphthalene and 1-Azido-4-iodobenzene added to liposomes and sarcoplasmic reticulum membranes, are able to reach the liquid hydrocarbon like core, as demonstrated by encounter quenching of perylene fluorescence. Photoactivation converts the azides into the reactive nitrenes which label covalently the fatty acyl chains of the phospholipids. In addition, approximately half of the radioactivity is associated with membrane proteins. Only some 25% is released by exhaustive pronase treatment. Gel electrophoresis shows that the label is located in the Ca++-stimulated Adenosine triphosphatase and in a high molecular weight polypeptide. These results are discussed in terms of possible labeling of biological membranes from within the lipid core. 相似文献
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Maha M. El‐Sawalhi Hebatallah A. Darwish Mohamed N. Mausouf Amira A. Shaheen 《Cell biochemistry and function》2013,31(6):518-525
Oxidative stress emerges as a key player in the ageing process. Controlled ozone administration is known to promote an oxidative preconditioning or adaptation to oxidative stress. The present study investigated whether prophylactic ozone administration could interfere with the age‐related changes in the heart and the hippocampus of rats. Four groups of rats, aged about 3 months old, were used. Group 1 (Prophylactic ozone group) received ozone/oxygen mixture by rectal insufflations (0.6 mg/kg) twice/week for the first 3 months, then once/week till the age of 15 months. Group 2 (Oxygen group) received oxygen as vehicle for ozone in a manner similar to group 1. Group 3 (Aged control group) was kept without any treatment until the age of 15 months. A fourth group of rats (Adult control group) was evaluated at 3 months of age to provide baseline data. Ozone alleviated age‐associated redox state imbalance as evidenced by reduction of lipid and protein oxidation markers, lessening of lipofuscin deposition, restoration of glutathione levels in both tissues and normalization of glutathione peroxidase activity in the heart tissue. Ozone also mitigated age‐associated energy failure in the heart and the hippocampus, improved cardiac cytosolic Ca2+ homeostasis and restored the attenuated Na+, K+‐ATPase activity in the hippocampus of aged rats. These data provide new evidence concerning the anti‐ageing potential of prophylactic ozone administration. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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