Biomedical subjects

K Fiskin

Publications and source records attributed to K Fiskin.

3 recordsLinked to original sources

PubMed1992

NGF restores decrease in catalase activity and increases superoxide dismutase and glutathione peroxidase activity in the brain of aged rats.

The effects of ageing on the activity of copper-zinc superoxide dismutase (SOD), selenium-dependent and independent glutathione peroxidase (GSH-Px) and catalase in several areas of the brain in 3-, 12-, and 24-month-old rats were studied. In addition, the effects of a subacute intracerebroventricular treatment of NGF (1 microgram daily for 28 consecutive days) on SOD, GSH-Px, and catalase activity in the same areas of the brain were assessed. The effects of ageing on the activities of antioxidant enzymes varied considerably in the different brain areas studied. Copper-zinc SOD was alone in being unaffected by ageing. Intraventricular infusion of NGF significantly increased SOD activity in the prefrontal cortex, hypothalamus, caudate nucleus, and mesencephalon of 24-month-old rats. Selenium-dependent GSH-Px activity did not significantly change in 12-month-old rats but it increased in the lower brain stem of 24-month-old animals. In comparison to vehicle-treated rats, NGF significantly increased selenium-dependent GSH-Px activity in all brain areas studied in 12- and 24-month-old rats. Catalase activity decreased significantly in the majority of the brain areas studied in 12- and 24-month-old rats. NGF completely restored the fall in catalase activity in 12- and 24-month-old animals to levels similar to those occurring in young rats. In conclusion, the present experiments show, for the first time, that long-term intraventricular administration of NGF significantly increases in old animals the activity of key enzymes involved in the metabolic degradation of superoxide radicals and hydrogen peroxide.

Aging↗

PubMed1991

Age-related changes in Cu,Zn superoxide dismutase, Se-dependent and -independent glutathione peroxidase and catalase activities in specific areas of rat brain.

Oxidative injury of tissues involves both accumulation of damage due to persistent oxidative stress and loss of the proper balance of antioxidative enzymes. These events may produce a faster rate of tissue senescence. In this regard, we have assayed the antioxidative enzyme activities (Cu,Zn superoxide dismutase, glutathione peroxidase and catalase), in various areas of rat brain (prefrontal cortex, parietal cortex, hippocampus, hypothalamus, caudate nucleus, mesencephalon and lower brain stem) for the age groups of 3, 6, 12, 24 months. The results obtained show that the levels of antioxidant enzyme activities differed considerably in the various brain parts studied. Furthermore, changes in the specific activities of superoxide dismutase, catalase, and glutathione peroxidase did not follow the same pattern as a function of aging. In particular, in prefrontal cortex and caudate nucleus, superoxide dismutase and glutathione peroxidase activities did not change, while catalase activity decreased. In parietal cortex and mesencephalon, superoxide dismutase and glutathione peroxidase activities increased, but the catalase activity decreased in parietal cortex and did not change in mesencephalon. In lower brain stem, the activities of glutathione peroxidase and catalase decreased in 3-12-month-old rats. The activity of glutathione peroxidase was increased in the hippocampus and was decreased in hypothalamus during aging. In this area the catalase activity was also significantly diminished.

Aging↗

PubMed1991

NGF restores decrease in catalase and increases glutathione peroxidase activity in the brain of aged rats.

The effects of subchronic administration of nerve growth factor (NGF) into the lateral ventricle on catalase and selenium-dependent glutathione-peroxidase (GSH-Px) activity in several areas of the brain in 3-, 12- and 24-month-old rats were studied. NGF given daily (1 microgram for 28 consecutive days) produced in all brain areas studied a significant increase in catalase activity in 12- and 24-month-old rats. The most important finding was a complete restoration in 12- and 24-month-old rats of catalase activity to levels similar to those occurring in young (3-month-old) rats. In addition, NGF produced in comparison to 3-month-old rats and to same age vehicle-treated rats a significant increase in selenium-dependent GSH-Px in all the brain areas studied in 12- and 24-month-old animals, whereas selenium-independent GSH-Px was unaffected. In conclusion, the present results show that long-term administration of NGF into the lateral ventricle significantly increases in old animals the activity of key enzymes involved in the metabolic degradation of hydrogen peroxide.

Aging↗