5627
Esraa Abdel Aziz Ahmed Ali
Effect Of Different Hibiscus Sabdariffa
Extracts On Glutathione And Its Related
Enzymes In Mammalian Lung Tissues And
Cultured Cells Under Induced Oxidative
Stress
Oxidative stress, polyphenols,
antioxidant and prooxidant abilities,
antioxidant enzymes, glutathione, lung
tissue, fibroblast.
Oxidative stress refers to the excessive ROS production and the antioxidant system cannot be able to neutralize them. HPLC analysis of aqueous, 30% and 70% ethanol extracts of the polyphenol rich H. sabdariffa calyx (the highest phenolic, flavonoid, anthocyanin contents and antioxidant capacities) showed that cyanidin 3-O-glucoside chloride, chlorogenic acid and delphinidin derivatives were the major constituents. Production of H2O2 (prooxidant capacity) increased by increasing the ethanol extracts concentration and incubation time at pH 7.4. Gallic acid was the greatest in the production of H2O2. Pretreatment of rats with H. sabdariffa ethanol extract followed by tertbutyl hydroperoxide (t-BHP) injection partially blocked the effect of the t-BHP, as indicated by the oxidative stress markers. In rat lungs homogenates, glutathione, malondialdehyde levels and lactate dehydrogenase activity returned back almost to the normal level. The antioxidant enzymes catalase and glutathione S-transferase (GST) were increased, while glutathione peroxidase (GPx) and glutathione reductase (GR) were not affected. Histological studies indicated the presence of sever lung injury with t-BHP and H. sabdariffa extracts. In human lung fibroblast cells, H. sabdariffa extracts (150 μg and 300 μg) have almost no effect on GST activity while, resolved the inhibitory effect of H2O2 on GR and GPx activity.
2018
Ph.d
Cairo
Science