Ferda Hosgorler

Although studies suggest that cognitive functions in the elderly are impaired, elderly people tend to be more successful and wiser in solving emotional problems. In empathy-like behavior models, the observer rat rescues the distressed cage mate by displaying emotional and cognitive ability. The aim of the study was to investigate the changes in empathy-like behavior in older rats in comparison to adult rats. In addition, we wanted to determine the effects of alterations in neurochemicals (such as corticosterone, oxytocin, vasopressin, and their receptor levels) and emotional situations on this behavior. In our study, we initially completed empathy-like behavior tests and emotional tests (open field, elevated plus maze) and performed neurochemical examinations in the serum and brain tissues. In the second step of research, we applied a midazolam (benzodiazepine) treatment to examine the effect of anxiety on empathy-like behavior. In the old rats, we observed that empathy-like behavior deteriorated, and anxiety signs were more pronounced. We detected a positive correlation between the latency in empathy-like behavior and corticosterone levels and v1b receptor levels. The midazolam effect on empathy-like behavior was attenuated by flumazenil (a benzodiazepine receptor antagonist). The recordings of ultrasonic vocalization showed frequencies around 50 kHz emitted by the observer and this was associated with the expectation of social contact. Our results state that compared to adult rats, old rats were more concerned and failed during empathy-like behavior. Midazolam may improve this behavior by anxiolysis.

Magnesium is being investigated in various clinical conditions and has shown to be effective in some chronic pain models. However, it is not clear if oral magnesium use affects pain perception in acute pain. TLR4’s (toll-like receptor) role in pain perception has emerged through its role in immune pathways and ion channels. The aim of this study is to investigate the effect of a single oral dose of magnesium citrate on pain conduction and whether with magnesium, the expression of TLR4 changes in the acute phase. Following a single dose of 66-mg/kg magnesium citrate administration to male Balb-c mice, pain perception (via hot-plate test), motor conduction (via electrophysiological recording, forelimb grip strength, rotarod and open-field tests), and emotional state (via elevated plus maze and forced swim test) were evaluated. In behavioral experiments, the control group was compared with applied magnesium for three different time groups (4, 8, 24 h). TLR4 expression was measured in four groups: control, magnesium (Mg), hot plate (HP), and Mg + HP. Hot plate latency was prolonged in the magnesium group (p < 0.0001) and electrophysiological recordings (p < 0.001) and forelimb grip strength measurement (p < 0.001) determined motor latency. Compared with the untreated hot plate group, TLR4 levels was lower in the brain (p = 0.023) and higher in the sciatic nerve (p = 0.001) in the magnesium-treated hot plate group. Consequently, the study indicated a single dose of magnesium citrate appeared to cause weakening in the transmission and perception of nociceptive pain. TLR4 may act as a regulator in magnesium’s effects on pain perception.

Hypoxia occurs in the splanchnic region during exercise associated with sympathetic activity. In the elderly, vascular insufficiency and low vascular endothelial growth factor (VEGF) expression are observed. Compared to young people, sympathetic signals of older individuals are blunted and more resistant to splanchnic blood flow alterations during exercise. VEGF induces vasodilation responses and hence may retain blood in the splanchnic vascular bed. We hypothesized that regular mild-intensity exercise triggers weak VEGF expression in the digestive tract of the elderly. The effects of exercise on the levels of VEGF, superoxide dismutase (SOD), glutathione peroxidase (GPx), malondialdehyde (MDA) and total antioxidant capacity (T-AOC) in the stomach, jejunum, ileum and colon tissues were evaluated. With exercise, the VEGF levels in the stomach and colon increased. Although the SOD, GPx, and MDA levels decreased in the stomach, they increased in the colon. T-AOC increased in the stomach and there was no change in the jejunum, ileum and colon. The hypoperfusion during exercise was not equal in all regions of the gastrointestinal tract in the aged subjects. Hypoxia and other exercise-related mechanisms could have led to this VEGF induction. The stomach, jejunum, and ileum might have developed resistance to ischemia. The induction of VEGF may be beneficial in aging-associated impaired gastrointestinal homeostasis and neovascularization.

AIM: To investigate the effects of different magnesium forms on tissue damage, cognitive and emotional behavioural impairment after mild traumatic brain injury (TBI). MATERIAL and METHODS: Rats were divided into 5 groups (control, trauma, magnesium sulphate, magnesium citrate, magnesium acetyl taurate) and following head trauma, empathy-like behaviour, anxiety-like behaviour (elevated plus maze and open field tests), and depression (forced swim test) were measured. The rats were then sacrificed 12 days later. Oxytocin, vasopressin and receptors levels in the amygdala and prefrontal cortex regions were measured. Histopathological damage (with haematoxylin-eosin staining) and apoptosis (with caspase-3 immunohistochemistry) was evaluated. RESULTS: Following head trauma, anxiety-like behaviour and depression tests did not change; empathy-like behaviour deteriorated on the 3rd day and improved gradually on the 6th and 12th days. Oxytocin, vasopressin and vasopressin v1b receptor levels decreased in the amygdala; morphological damage and apoptosis were significant. Magnesium acetyl taurate effectively ameliorated histopathological deteriorations and improved vasopressin and v1b receptor levels in the amygdala. Transient deterioration of empathy-like behaviour was impeded only in magnesium taurate treatment. CONCLUSION: Magnesium acetyl taurate can be a promising candidate agent to prevent structural and functional damage in traumatic brain injury.

Objective: In the elderly, erectile dysfunction and hypogonadism have become more important due to the extension of human life. The most important morphological changes of the aged testis are associated with vascular deterioration, chronic hypoxia, fibrosis and hormonal changes. Vascular Endothelial Growth Factor (VEGF) and Matrix Metalloproteinase-2 (MMP-2) are directly related to these changes along with sperm motility and viability. The contribution of VEGF and MMP-2 to the structural and functional disturbances in the aged testis is unknown. The aim of this study was to determine VEGF and MMP-2 levels in the elderly testis and their interactions with one another. Method: The testis tissues of aged rats (26-30 months) and adult rats (8-10 months) were analysed using the ELISA method to determine MMP-2 and VEGF levels. Serum total testosterone levels were analyzed using the immunoassay method. The statistical analysis was performed using the Mann Whitney-U test, p<0.05 was considered significant. The results were presented with median and percentile values. Results: In contrast to the adult testis, we observed that VEGF levels were increased [0.18(0.16-0.20) to 0.30(0.28-0.32) g/mg respectively, p=0.009] and MMP-2 levels decreased [3.70 (2.07-4.74) to 1,10 (1,08-1,29) g/mg respectively, p=0.03] in the aged testis. Serum total testosterone levels were lower in the aged group [5.45 (4.04-6.95) and 2.48 (1.93-3.11) ng/ml, p=0.004]. Conclusion: Low levels of MMP-2 are consistent with deficiency of reproductive function but interestingly, VEGF levels were found to be high. MMPs have the potential to regulate the levels and activities of hormones. The absence of physiological effects of VEGF may be associated with MMP-2 deficiency. The therapeutic benefit of induction of MMP-2 activity in testicular hypogonadism is open to research.