Genetic modulation of the cellular antioxidant defense capacity.
نویسندگان
چکیده
Oxidants are ubiquitous in our aerobic environment. While they are always toxic, they can also exert pathophysiological effects at low concentrations and play an etiological role in human disease. For example, oxidants can stimulate cell growth and act as tumor promoters. The cellular antioxidant defense system attenuates the effect of oxidants and consists of low molecular weight components and several enzymes. Most important are catalase (CAT), superoxide dismutases (SOD), and glutathione peroxidase. We are attempting to elucidate the role of CAT and Cu,Zn-SOD in oxidant tumor promotion of mouse epidermal cells JB6. We have found that the promotable clone 41 possesses 2- to 3-fold higher levels of activity, protein, and stationary mRNA of CAT and Cu,Zn-SOD than does the nonpromotable clone 30. We propose that the growth-stimulatory effect of oxidants is more pronounced in promotable clone 41 because it is better protected from oxidant toxicity. In order to corroborate this model, we have constructed JB6 cells with higher levels of Cu,Zn-SOD and CAT by transfection with expression vectors containing cDNA for these genes. On the other hand, cells with decreased amounts of Cu,Zn-SOD have been obtained by their stable transfection with a vector containing SOD-cDNA in the antisense orientation. These cell clones with modified antioxidant enzyme complements are being characterized. In particular, their promotability by oxidants and their sensitivity to killing and oxidative macromolecular damage are being measured. Certain tumor promoters that lack oxidizing properties may generate a cellular prooxidant state by a variety of mechanisms.(ABSTRACT TRUNCATED AT 250 WORDS)
منابع مشابه
بررسی برخی عوامل مرتبط با ظرفیت آنتیاکسیدانی تام بزاق
Introduction: Free radicals are molecules or atoms with single electron that results in reactions thus causing severe damages to the body’s macromolecules. By preventing the formation of free radicals, repairing damages caused by radical’s activities, increasing the excretion of the damaged molecules and minimizing the cellular mutation, the antioxidant defense system contrasts the damages caus...
متن کاملCadmium stress consolation in melatonin supplemented Cucumis sativus through modulation of antioxidative defense system
Current studies elucidate the metal stress attenuation potential of melatonin in Cucumis sativus seedlings growing in cadmium contaminated conditions. Melatonin is an indoleamine molecule, capable of ameliorating environmental stresses and regulate plant growth. Seeds of C. sativus were immersed in different levels of melatonin and grown under cadmium stress for 15 days. Cadmi...
متن کاملComparing the Effects of Rosemary Extract and Treadmill Exercise on the Hippocampal Function and Antioxidant Capacity in Old Rats
Background: A sequence of time-dependent changes can affect the brainchr('39')s functional capacity. Aims: This study aimed at investigating the effects of forced aerobic exercise (FAE) versus the rosemary extract (RE) on the learning abilities and oxidative stress modulation in rats. Methods: Young and old rats received daily FAE and RE for 3 months. Using the passive avoidance (PA) test, we...
متن کاملSimple and Sensitive Method of Fluorometry for Determination of Total Antioxidant Capacity
Background and Objective: Oxidative stress plays an important role in the pathogensis of various diseases, including lung cancer, chronic obstructive pulmonary disease, and atherosclerosis. Total antioxidant capacity plays a significant role in the body’s antioxidant defense, so its assessment is a matter of the utmost importance. Currently, assessment of this capacity is performed in var...
متن کاملEffects of Piperine Pretreatment on Antioxidant Capacity and Spatial Memory Impairment Induced by Local Injection of Lysolecethin in Rat Hippocampus
Background and purpose: Piperine as the main alkaloid of black pepper has antioxidant and neuroprotective properties, so, it is an appropriate candidate to be studied in animal models of multiple sclerosis. This research aimed at investigating the effect of pretreatment with piperine on spatial memory, oxidative stress, and myelin repair gene markers in local demyelination model. Materials and...
متن کاملIn vitro antioxidant effects of barberry fruit extracts
A vast majority of the studies addressing the free radicals including hydroxyl radical is a damage compound of biochemical molecules such as DNA, proteins and lipids. When free radicals specially hydroxyl radical are not adequately removed from the body, it may damage biological macromolecules, leading to a variety of disease occurs. Therefore, the body should be protected by an enzymatic or no...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Environmental Health Perspectives
دوره 88 شماره
صفحات -
تاریخ انتشار 1990