Diagnostic and Therapeutic Significance of the Oxidative Stress Parameters in Children

The Impact of Senile Cataract Maturity on Blood Oxidative Stress Markers and Glutathione-Dependent Antioxidants: Relations with Lens Variables

Oxidative stress is implicated in senile cataract (SC) genesis, although the impact of SC maturity on blood oxidative stress markers is unclear. Total hydroperoxides, malondialdehyde (MDA), glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione S-transferase (GST) were measured in the blood and lens samples of patients having either immature (n=31) or mature SC (n=50), and in 22 blood samples from noncataract controls. Compared to controls, SC patients had higher plasma MDA and serum GST, and decreased plasma GR and GSH levels. Plasma GPx as well as hydroperoxides differed from control values only in patients with mature SC. The multivariate logistic regression analysis showed that the fall of plasma GR activity (OR 5.14; CI 1.82-14.51;p=0.0020), as well as serum GST activity (OR 3.84; CI 1.36-10.83;p=0.0108) were independently associated with the maturity of SC. Lens hydroperoxides, MDA and GST, showed no correlation with correspondent blood values, in contrast to GPx (r=0.715; p<0.001) and GR (r=0.703; p<0.001). This study showed that the severity of SC is associated with increased systemic oxidative stress, which could be due to the fall of GSH-dependent antioxidant enzymes activities.

Aspects Regarding the Neurobiology of Psycho-Affective Functions

In this mini-review we were interested in analyzing the main achievements concerning the neurobiological substrate of the human psycho-affective functions. The cortico-subcortical areas implicated in the elaboration and the control of the sensorial and psycho-affective reactions of the human brain are described, as well as the neurobiological basis of the psychic and affective manifestations, with focus on the new achievements in understanding the genetic, morpho-chemical and electromagnetic bases of the psycho-affective and behavioral manifestations, both normal and pathological. It is known that emotional states like anxiety, fear or anger generate complex psycho-affective reactions that are controlled by the limbic system, which is called the emotional brain. This is connected with the polyneuronal circuits of the Papez loop, the hypothalamic-pituitary complex and the reticular formation of the brainstem. Some imagistic aspects concerning the implication of the amygdala and the cingulate gyrus in laughing and crying are mentioned, as well as the cerebral areas implicated in romantic and maternal love. Also, some electromagnetic manifestations of the brain are presented, introducing the concept of «electromagnetic plasma», as a possible component of the human brain activity.

Antioxidative Enzyme Activities and Lipid Peroxidation in Children with Inflammatory Endothelial Injury

During the inflammatory process endothelial cells are activated and a proadherent ability is assumed. The synthesis of reactive oxygen metabolites, which follows the immunological processes, can cause oxidative damage to endothelial cells leading to the clinical expression of disease including a variety of skin manifestations. In this study the activity of antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase) and the malondialdehyde concentration were examined in 36 children with inflammation-mediated damage to microvascular endothelial cells. On the basis of clinical manifestations the studied children were divided into 4 groups (1st group-macular skin manifestations, 2nd group-maculo-papular skin manifestations, 3rd group-papular skin manifestations, 4th group- erythematous skin manifestations). All the examined children showed symptoms of inflammation (mainly respiratory tract infections) with leukocytosis and monocytosis before actual skin manifestations took place. Superoxide dismutase activity was significantly decreased in three groups of patients, except in the group with erythematous skin manifestations. Catalase activity was significantly increased in all the groups compared to the control group. The values of malondialdehyde were significantly increased in the groups of children with maculo-papular and erythematous skin manifestations. The results have confirmed the presence of a changed antioxidant enzyme pattern indicating oxidative stress during inflammatory endothelial cells injury. Malondialdehyde was not an adequate parameter in its evaluation.

Inhibition of Central Angiotensin Converting Enzyme Exerts Anxiolytic Effects by Decreasing Brain Oxidative Stress

This study investigated the effects of angiotensin II and captopril intracerebroventricular administration on anxiety status and brain oxidative stress. Elevated plus maze was used in order to asses the anxiety-like behavior, while the biochemical analysis included the determination of some antioxidant defense enzymes like superoxide dismutase and glutathione peroxidase and also a lipid peroxidation product (malondialdehyde). Our results provide additional evidence of angiotensin II induced anxiety-like effects and increased prooxidant status. Moreover, the blockade of angiotensin II, by the administration of an angiotensin converting enzyme inhibitor (captopril) resulted in anxiolytic effects and decreased oxidative stress status. In addition, we found a significant correlation between the time spent by rats in the open arms of the elevated plus maze and oxidative stress markers. This could raise important therapeutic issues regarding the anxiolytic effects of some angiotensin converting enzyme inhibitors used primarily for hypertension, such as captopril. Also, it seems that oxidative stress could play an important part in these actions.

Age-Related Blood Antioxidant Capacity in Men and Women

The aim of the study was to assess the blood antioxidant capacity in men and women in relation to age. The subjects were 19 men (YM) and 19 women (YW) aged 25-32 years, and 11 men (OM) and 11 women (OW) aged 63-71 years, all sedentary. The following factors were determined: the activity of erythrocyte superoxide dismutase (SOD), glutathione reductase (GR), glutathione peroxidase (GPX), catalase (CAT), total antioxidant status (TAS), as well as plasma retinol, α-tocopherol, uric acid and total protein concentrations. The sum of standardized activities of antioxidant enzymes was calculated to compare age-related changes in the total capacity of the erythrocyte antioxidant defense. No significant age-related changes in SOD activity were observed; mean CAT activity was higher in older women and men than in younger subjects. Mean activity of GPX was higher and that of GR lower in older subjects compared to the younger ones. The calculated total erythrocyte antioxidant enzyme capacity in younger and older subjects rendered similar values. No significant differences in plasma retinol and α-tocopherol concentrations in relation to sex or age were noted. The plasma total protein level was significantly lower in younger women and men compared to their older mates. It was concluded that the total erythrocyte enzymatic antioxidant capacity did not change with age. The results obtained clearly show that multiple factors may contribute to the ageing process.