Decreased blood flow in the brain leads to a rapid increase in reactive oxygen species (ROS). NADPH oxidase (NOX) is an enzyme family that has the physiological function to produce ROS. NOX2 and NOX4 overexpression is associated with aggravated ischemic injury, while NOX2/4‐deficient mice had reduced stroke size. Dysregulation of matrix metalloproteinases (MMPs) contributes to tissue damage. The active form of vitamin D3 expresses neuroprotective, immunomodulatory, and anti‐inflammatory effects in the CNS. The present study examines the effects of the vitamin D3 pretreatment on the oxidative stress parameters and the expression of NOX subunits, MMP9, microglial marker Iba1, and vitamin D receptor (VDR), in the cortex and hippocampus of Mongolian gerbils subjected to ten minutes of global cerebral ischemia, followed by 24 hours of reperfusion. The ischemia/reperfusion procedure has induced oxidative stress, changes in the expression of NOX2 subunits and MMP9 in the brain, and increased MMP9 activity in the serum of experimental animals. Pretreatment with vitamin D3 was especially effective on NOX2 subunits, MMP9, and the level of malondialdehyde and superoxide anion. These results outline the significance of the NOX and MMP9 investigation in brain ischemia and the importance of adequate vitamin D supplementation in ameliorating the injury caused by I/R.

Background/Aim. Previous studies on medical students? subjective perception of health and health-related quality of life (HRQoL) showed inconclusive results. Moreover, there are no published studies to compare HRQoL of medical students to non-medical university students. The aim of the study was to assess subjective perception of health-related quality of life (HRQoL) in medical students? sample, to compare it with non-medical university stu-dents and to ascertain predictors of better perception of HRQoL in medical students. Methods. Scores of all domains on the Mental and Physical Component Summary subscales and total score of the Short Form Health Survey (SF-36), used for assessment of HRQoL in samples of 561 medical and 332 non-medical university students were assessed and compared. In addition, linear regression to identify predictors of better perception of mental and physical components of HRQoL and overall HRQoL in the sample of medical students was used. The dependant variables were subscores and total score with the SF- 36, and independent variables were certain sociodemographic and academic characteristics of the students. Results. Medical students had statistically significantly higher scores on the Mental Component Summary and total SF-36 score compared to non-medical students. Linear regression analysis demonstrated that higher scores of Physical Component Summary were associated with age, male sex and the year of studies. The Mental Component Summary were associated with age, male sex, the year of studies and marital status. The total SF-36 score was associated with age, male sex and the year of studies. Conclusion. Medical students perceive their health much better than other university students do, but female, older and second grade medical students have worse perception of their HRQoL. Those points should be potential target areas for specific prevention and treatment in order to achieve better HRQoL.

The aim of this study was to examine the effects of a methionine-enriched diet on anxiety-related behavior in rats and to determine the role of the brain oxidative status in these alterations. Adult male Wistar rats were fed from the 30th to 60th postnatal day with standard or methionine-enriched diet (double content comparing with standard diet: 7.7 g/kg). Rats were tested in open field and light–dark tests and afterwards oxidative status in the different brain regions were determined. Hyperhomocysteinemia induced by methionine-enriched diet in this study decreased the number of rearings, as well as the time that these animals spent in the center of the open field, but increased index of thigmotaxy. Oxidative status was selectively altered in the examined regions. Lipid peroxidation was significantly increased in the cortex and nc. caudatus of rats developing hyperhomocysteinemia, but unaltered in the hippocampus and thalamus. Based on the results of this research, it could be concluded that hyperhomocysteinemia induced by methionine nutritional overload increased anxiety-related behavior in rats. These proanxiogenic effects could be, at least in part, a consequence of oxidative stress in the rat brain.

Tryptophan (TRP) catabolites exert neuroactive effects, with the plethora of evidence suggesting that kynurenic acid (KYNA), a catabolite of the kynurenine pathway (KP), acts as the regulator of glutamate and acetylcholine in the brain, contributing to the schizophrenia pathophysiology. Newer evidence regarding measures of KP metabolites in the blood of schizophrenia patients and from the central nervous system suggest that blood levels of these metabolites by no means could reflect pathological changes of TRP degradation in the brain. The aim of this study was to investigate plasma concentrations of TRP, kynurenine (KYN) and KYNA at the acute phase and remission of schizophrenia in a prospective, case-control study of highly selected and matched schizophrenia patients and healthy individuals. Our study revealed significantly decreased KYN and KYNA in schizophrenia patients (p < 0.001), irrespective of illness state, type of antipsychotic treatment, number of episodes or illness duration and no differences in the KYN/TRP ratio between schizophrenia patients and healthy individuals. These findings could be interpreted as indices that kynurenine pathway might not be dysregulated in the periphery and that other factors contribute to observed disturbances in concentrations, but as our study had certain limitations, we cannot draw definite conclusions. Further studies, especially those exploring other body compartments that participate in kynurenine pathway, are needed.

Although previous studies indicated that chronic alcohol abuse (CAA) and alcoholic liver cirrhosis (ALC) are associated with increased bone fragility, understanding bone fragility determinants is still modest in these individuals. We used a comprehensive individualized clinical fracture risk assessment approach (vertebral osteodensitometry, femoral osteodensitometry and geometry, and serum bone turnover biomarkers) to compare adult male patients with ALC who have not previously had femoral or vertebral fractures (n = 39), patients with CAA (without liver cirrhosis, n = 78) who have not previously had femoral or vertebral fractures and healthy age- and sex-matched controls (n = 43). Our data suggested that intertrochanteric bone mineral density was significantly lower in ALC and CAA patients than in controls. Also, the trabecular bone score was considerably lower in ALC patients compared with CAA and control individuals. The most significant inter-group differences in femoral geometry were noted on the femoral shaft. Patients with ALC and CAA have a higher 10-year risk of major osteoporotic fractures compared to the controls. Analysis of bone turnover biomarkers showed increased osteoprotegerin and beta-C-terminal telopeptide serum concentrations and decreased insulin growth factor-1 concentrations in patients with ALC compared to CAA and control groups. Our data revealed that bone alterations are present in patients with ALC and CAA even if they did not sustain a nontraumatic bone fracture, but it is also indicative that current bone-assessing clinical methods are not entirely reliable. Thus, future studies should focus on developing a reliable integrative clinical tool that can be used to accurately predict and prevent bone fracture occurrences in patients with ALC and CAA.