A comprehensive analysis on glutathione metabolism in rat cerebral cortex synaptosomes as a function of age was performed. All different glutathione system components (GSH, GSSG, total GSH, and GSH redox index) changed significantly only during aging. GSH, total GSH, and GSH redox index decreased by about 40%, 24%, and 52%, respectively, while GSSG showed a remarkable increase of about 60%. On the contrary, some GSH-related enzyme activities showed characteristic changes both during growth and aging. GSH peroxidase and GSH-S-transferase activities significantly increased both during growth and aging, GSH reductase and gamma-glutamylcysteine synthetase activities showed lower levels only during aging, while glucose-6-phosphate dehydrogenase activity did not change throughout the life of the rat. The results obtained suggest an increase of the oxidative status due to a reduced antioxidant capacity of the GSH system in the synaptosomal compartment during aging. The main cause of these metabolic modifications is a lowering of the rates of both GSSG reduction to GSH and GSH synthesis. Moreover, an irreversible loss of GSH as GSH-S-conjugates due to a high detoxification mechanism during aging is also possible. These alterations in glutathione metabolism, found mainly during aging in rat cerebral cortex synaptosomes may contribute to clarify some aspects of cerebral diseases.

Aging↗

PubMedDate not supplied

Glutathione metabolism in heart and liver of the aging rat.

A comprehensive study on glutathione metabolism in rat heart and liver as a function of age was performed. In the heart, reduced glutathione, total glutathione, and the glutathione redox index showed a decrease during aging, while oxidized glutathione levels increased in 5-month-old rats with respect to the young animals and remained quite constant in 14- and 27-month-old rats. In the liver, the highest levels of reduced glutathione were found in the 2-month-old rats, while oxidized glutathione reached a peak at 5 months. Glutathione-associated enzymes showed age-related changes. Glutathione peroxidase, unaffected by aging in the heart, decreased in the liver of the 27-month-old rats. In the heart and the liver, the highest values of glutathione S-transferase were found at 5 months and 27 months, respectively. Glucose-6-phosphate dehydrogenase followed a similar trend in both heart and liver. Glutathione reductase also showed the same behaviour in heart and in liver, increasing in old rats with respect to the other age groups. A decrease in gamma-glutamylcysteine synthetase was found in the heart and liver of 27-month-old rats in comparison with the 2-month-old ones. In conclusion, a decreased antioxidant capability has been demonstrated in both heart and liver of old rats.

Aging↗

PubMedDate not supplied

Changes in enzyme levels in human cervical mucus during the menstrual cycle.

Cervical mucus is a complex secretion produced by the endocervical epithelium. A comparative analysis of 30 enzymes was carried out on 15 women during their periovulatory period (days 10 to 16 of the menstrual cycle). Nine different enzymes were always found to be present in the cervical mucus. Changes in enzymatic activity were further studied in two of the women, one with a normal (27-day) and the other with a short (20-day) menstrual cycle. The data were compared with those for the same enzymes in the saliva of these two women. Each woman's ovulation time was determined through hormone measurements in urine and blood, as well as by recording basal body temperature and by Billing's method. Our results indicate that a maximum peak occurs for several enzymes during the periovulatory period.

Adult↗

PubMedDate not supplied

Some molecular features of human cervical mucus.

1) The time preservation effect of the enzymatic activities present in human cervical mucus has been studied. 2) In order to protect the enzymatic activities of the mucus from bacterial impurities, the enzymes studied were assayed in presence of NaN3. 3) The effect of an acid pH likes present in the vagina was also studied: a low pH exerts a marked inhibition on mucus enzymes. 4) the use of nonionic detergents for mucus solubilization does not produce a marked increase of the enzymatic activities studied. 5) A NADP-dependent malate dehydrogenase in peri- and post-ovulatory period has been identified. 6) The presence in mucus of at least four lactate dehydrogenase isoenzymes has been demonstrated and their absolute values determined.

Cervix Mucus↗