Reduced light exposure mitigates streptozotocin-induced vascular changes and gliosis in diabetic retina by an anti-inflammatory effect and increased retinal cholesterol turnover

Diabetic retinopathy is not cured efficiently and changes of lifestyle measures may delay early retinal injury in diabetes. The aim of our study was to investigate the effects of reduced daily light exposure on retinal vascular changes in streptozotocin (STZ)-induced model of DM with emphasis on inflammation, Aqp4 expression, visual cycle and cholesterol metabolism-related gene expression in rat retina and RPE. Male Wistar rats were divided into the following groups: 1. control; 2. diabetic group (DM) treated with streptozotocin (100 mg/kg); 3. group exposed to light/dark cycle 6/18 h (6/18); 4. diabetic group exposed to light/dark cycle 6/18 h (DM+6/18). Retinal vascular abnormalities were estimated based on lectin staining, while the expression of genes involved in the visual cycle, cholesterol metabolism, and inflammation was determined by qRT-PCR. Reduced light exposure alleviated vasculopathy, gliosis and the expression of IL-1 and TNF-α in the retina with increased perivascular Aqp4 expression. The expression of genes involved in visual cycle and cholesterol metabolism was significantly up-regulated in RPE in DM+6/18 vs. DM group. In the retina only the expression of APOE was significantly higher in DM+6/18 vs. DM group. Reduced light exposure mitigates vascular changes and gliosis in DM via its anti-inflammatory effect, increased retinal cholesterol turnover and perivascular Aqp4 expression.

Adipose-derived extracellular vesicles - a novel cross-talk mechanism in insulin resistance, non-alcoholic fatty liver disease, and polycystic ovary syndrome

Obesity is the best described risk factor for the development of non-alcoholic fatty liver disease (NAFLD)/metabolic dysfunction associated steatotic liver disease (MASLD) and polycystic ovary syndrome (PCOS) while the major pathogenic mechanism linking these entities is insulin resistance (IR). IR is primarily caused by increased secretion of proinflammatory cytokines, adipokines, and lipids from visceral adipose tissue. Increased fatty acid mobilization results in ectopic fat deposition in the liver which causes endoplasmic reticulum stress, mitochondrial dysfunction, and oxidative stress resulting in increased cytokine production and subsequent inflammation. Similarly, IR with hyperinsulinemia cause hyperandrogenism, the hallmark of PCOS, and inflammation in the ovaries. Proinflammatory cytokines from both liver and ovaries aggravate IR thus providing a complex interaction between adipose tissue, liver, and ovaries in inducing metabolic abnormalities in obese subjects. Although many pathogenic mechanisms of IR, NAFLD/MASLD, and PCOS are known, there is still no effective therapy for these entities suggesting the need for further evaluation of their pathogenesis. Extracellular vesicles (EVs) represent a novel cross-talk mechanism between organs and include membrane-bound vesicles containing proteins, lipids, and nucleic acids that may change the phenotype and function of target cells. Adipose tissue releases EVs that promote IR, the development of all stages of NAFLD/MASLD and PCOS, while mesenchymal stem cell-derived AVs may alleviate metabolic abnormalities and may represent a novel therapeutic device in NAFLD/MASLD, and PCOS. The purpose of this review is to summarize the current knowledge on the role of adipose tissue-derived EVs in the pathogenesis of IR, NAFLD/MASLD, and PCOS.

The Interconnection between Hepatic Insulin Resistance and Metabolic Dysfunction-Associated Steatotic Liver Disease-The Transition from an Adipocentric to Liver-Centric Approach

The central mechanism involved in the pathogenesis of MAFLD is insulin resistance with hyperinsulinemia, which stimulates triglyceride synthesis and accumulation in the liver. On the other side, triglyceride and free fatty acid accumulation in hepatocytes promotes insulin resistance via oxidative stress, endoplasmic reticulum stress, lipotoxicity, and the increased secretion of hepatokines. Cytokines and adipokines cause insulin resistance, thus promoting lipolysis in adipose tissue and ectopic fat deposition in the muscles and liver. Free fatty acids along with cytokines and adipokines contribute to insulin resistance in the liver via the activation of numerous signaling pathways. The secretion of hepatokines, hormone-like proteins, primarily by hepatocytes is disturbed and impairs signaling pathways, causing metabolic dysregulation in the liver. ER stress and unfolded protein response play significant roles in insulin resistance aggravation through the activation of apoptosis, inflammatory response, and insulin signaling impairment mediated via IRE1/PERK/ATF6 signaling pathways and the upregulation of SREBP 1c. Circadian rhythm derangement and biological clock desynchronization are related to metabolic disorders, insulin resistance, and NAFLD, suggesting clock genes as a potential target for new therapeutic strategies. This review aims to summarize the mechanisms of hepatic insulin resistance involved in NAFLD development and progression.

Shortened Daily Photoperiod Alleviates Anxiety-like Behaviour by Antioxidant Effect and Changes Serum Fatty Acid Profile in Diabetic Rats

The aim of our study was to investigate the effects of a shortened daily photoperiod on anxiety-like behaviour, brain oxidative stress, lipid status and fatty acid composition of serum lipids in a streptozotocin (STZ)-induced model of diabetes mellitus in rats. Male Wistar rats were divided into the following groups: first group-control group (C_12/12); second group-diabetic group (DM_12/12; 100 mg/kg STZ); third group-control group exposed to a light/dark cycle 6/18 h (C_6/18); fourth group-diabetic group exposed to a light/dark cycle 6/18 h (DM_6/18). Anxiety-like behaviour was tested three weeks following STZ injection by elevated plus maze (EPM) and open-field test (OFT). Oxidative stress parameters were measured in the cortex, hippocampus and thalamus, while lipid status and fatty acid methyl esters (FAMEs) were measured in the serum. Both EPM and OFT showed a lower degree of anxiety-like behaviour in the DM_6/18 vs. DM_12/12 group. Lipid peroxidation in the cortex, hippocampus and thalamus was significantly lower in the DM_6/18 vs. DM_12/12 group (p < 0.05), associated with an increased level of antioxidant enzymes and protein thiols in the cortex and thalamus. In the DM_6/18 group, oleic, vaccenic, dihomo-γ-linolenic and docosahexaenoic acid concentrations were significantly higher in comparison to the DM_12/12 group. A shortened daily photoperiod alleviates anxiety-like behaviour in diabetic rats by reduced lipid peroxidation and changes in the serum fatty acids profile.

Chronic Prostatitis/Chronic Pelvic Pain Syndrome Induces Depression-Like Behavior and Learning-Memory Impairment: A Possible Link with Decreased Hippocampal Neurogenesis and Astrocyte Activation

Pathogenesis of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) remains unclear since it represents an interplay between immunological, endocrine, and neuropsychiatric factors. Patients suffering from CP/CPPS often develop mental health-related disorders such as anxiety, depression, or cognitive impairment. The aim of this study was to investigate depression-like behavior, learning, and memory processes in a rat model of CP/CPPS and to determine the alterations in hippocampal structure and function. Adult male Wistar albino rats (n = 6 in each group) from CP/CPPS (single intraprostatic injection of 3% λ-carrageenan, day 0) and Sham (0.9% NaCl) groups were subjected to pain threshold test (days 2, 3, and 7), depression-like behavior, and learning-memory tests (both on day 7). Decreased pain threshold in the scrotal region and histopathological presence of necrosis and inflammatory infiltrate in prostatic tissue confirmed the development of CP/CPPS. The forced swimming test revealed the depression-like behavior evident through increased floating time, while the modified elevated plus maze test revealed learning and memory impairment through prolonged transfer latency in the CP/CPPS group in comparison with Sham (p < 0.001 and p < 0.001, respectively). Biochemical analysis showed decreased serum levels of testosterone in CP/CPPS group vs. the Sham (p < 0.001). The CP/CPPS induced a significant upregulation of ICAM-1 in rat cortex (p < 0.05) and thalamus (p < 0.01) and increased GFAP expression in the hippocampal astrocytes (p < 0.01) vs. Sham, suggesting subsequent neuroinflammation and astrocytosis. Moreover, a significantly decreased number of DCX+ and Ki67+ neurons in the hippocampus was observed in the CP/CPPS group (p < 0.05) vs. Sham, indicating decreased neurogenesis and neuronal proliferation. Taken together, our data indicates that CP/CPPS induces depression-like behavior and cognitive declines that are at least partly mediated by neuroinflammation and decreased neurogenesis accompanied by astrocyte activation.

THE EFFECTS OF ENDOCRINE DISRUPTORS ON FEMALE GONADAL AXIS: AN UPDATE

Endocrine disruptors (EDs) are considered to have an impact on the function of reproductive axis at different levels as well on reproductive organs in both sexes. Complexity of female reproductive system influenced with various stressors including EDs lead to morphological and functional alterations. This is resulting in modulation of neuroendocrine regulation with consequent developmental irregularities and derangements, causative infertility, endometriosis as well as premature ovarian insufficiency or polycystic ovary syndrome. A number of experimental clues was obtained on female animal models using various EDs such as synthetic estrogens and phytoestrogens, neurotransmitters, pesticides or various chemicals. These substances lead towards consequent derangement of the neuroendocrine control of reproduction from early phases of reproductive development towards different phases of adult reproductive period. This text will address some novel insights into the effects of EDs on neuroendocrine regulation of gonadal axis, effects on ovaries as well on endometrium during implantation period.

Basic characteristics of EEG epileptiform discharges triggered by lindane in a model of experimental prostatitis

Introduction: Chronic prostatitis/Chronic Pelvic Pain Syndrome (CP/CPPS) is the most commonly diagnosed non-infectious prostatitis in urology. Studies have shown that CP/CPPS can induce neuroinflammation, which may result in CNS hyperexcitability and a tendency to develop epileptic seizures. Spike salvos are ictal EEG graph elements typical for the experimental model of lindane-induced seizures. There are a number of mathematical models for quantitative analysis of EEG, including the Fast Fourier Transform (FFT). It transforms the signal from time into the frequency domain, providing information on Power Spectral Densities (PSD). Aim: The aim of this study was to investigate the basic characteristics of epileptiform discharges induced by subconvulsive dose of lindane in rats, with experimentally induced CP/CPPS. Material and methods: CP/CPPS was induced by intraprostatic injection of 3% l-carrageenan in male Wistar albino rats. Animals with CP/CPPS were implanted with EEG registration electrodes, and then administered lindane (4 mg/kg, i.p, experimental group, n = 6 per group) or its solvent (DMSO, control group, n = 6 per group). An 8-channel EEG device was used in combination with software developed in the laboratory (NeuroSciLaBG). Ictal EEG epochs were extracted from the original signal and FFT analysis was performed to obtain information taking into account PSD in predefined frequency bands. Results: There was no ictal activity in the EEG of control animals. In experimental animals, ictal activity occurred and the mean duration of the ictal period was 2.06 s. FFT analysis revealed that the Alpha frequency range (7-15 Hz) was markedly dominant during ictal activity. Conclusion: The results of this study showed the characteristics of epileptiform discharges in animals with experimentally induced CP/CPPS. This study and animal model are suitable for future translational studies of the comorbidities of this syndrome.

The interplay between metabolic dysregulations and non-alcoholic fatty liver disease in women after menopause

The hypoestrogenic period after menopause and associated metabolic imbalance might facilitate the onset of non-alcoholic fatty liver disease (NAFLD) and its progression. The prevalence of NAFLD increases in patients experiencing premature ovarian insufficiency, as well as surgical or natural menopause. The postmenopausal period is characterized by dyslipidemia and insulin resistance associated with an increased influx of free fatty acids to the liver with consequent steatosis and further progression of NAFLD. More than half of postmenopausal women with diabetes mellitus type 2 suffer from NAFLD. It is suggested that estrogens slow the progression of chronic liver diseases by suppression of inflammation, improvement of mitochondrial function, alleviation of oxidative stress, insulin resistance, and fibrogenesis. The hyperandrogenic state of polycystic ovary syndrome (PCOS) is associated with the development of NAFLD in women of reproductive age, but it is difficult to extend these findings to menopause due to inappropriate diagnosis of PCOS after menopause. Lifestyle intervention, including physical activity and dietary regimens, remains the first-line preventive and therapeutic option for NAFLD. There are contradictory reports on the use of menopausal hormonal therapy (MHT) and NAFLD. It is necessary to investigate the potential effects of estradiol dose, progesterone type, selective estrogen receptor modulators and tissue-selective estrogen complex compounds on NAFLD development and progression in postmenopausal women. The present review aims to explore the pathophysiological and clinical aspects of liver metabolic disturbances in women after menopause, focusing on the possible preventive and therapeutic strategies in NAFLD, including the potential role of MHT.

Experimental Chronic Prostatitis/Chronic Pelvic Pain Syndrome Increases Anxiety-Like Behavior: The Role of Brain Oxidative Stress, Serum Corticosterone, and Hippocampal Parvalbumin-Positive Interneurons

Mechanisms of the brain-related comorbidities in chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) are still largely unknown, although CP/CPPS is one of the major urological problems in middle-aged men, while these neuropsychological incapacities considerably diminish life quality. The objectives of this study were to assess behavioral patterns in rats with CP/CPPS and to determine whether these patterns depend on alterations in the brain oxidative stress, corticosterone, and hippocampal parvalbumin-positive (PV+) interneurons. Adult male Wistar albino rats from CP/CPPS (intraprostatic injection of 3% λ-carrageenan, day 0) and sham (0.9% NaCl) groups were subjected to pain and anxiety-like behavior tests (days 2, 3, and 7). Afterwards, rats were sacrificed and biochemical and immunohistochemical analyses were performed. Scrotal allodynia and prostatitis were proven in CP/CPPS, but not in sham rats. Ethological tests (open field, elevated plus maze, and light/dark tests) revealed significantly increased anxiety-like behavior in rats with CP/CPPS comparing to their sham-operated mates starting from day 3, and there were significant intercorrelations among parameters of these tests. Increased oxidative stress in the hippocampus, thalamus, and cerebral cortex, as well as increased serum corticosterone levels and decreased number of hippocampal PV+ neurons, was shown in CP/CPPS rats, compared to sham rats. Increased anxiety-like behavior in CP/CPPS rats was significantly correlated with these brain biochemical and hippocampal immunohistochemical alterations. Therefore, the potential mechanisms of observed behavioral alterations in CP/CPPS rats could be the result of an interplay between increased brain oxidative stress, elevated serum corticosterone level, and loss of hippocampal PV+ interneurons.

Experimental chronic sleep fragmentation alters seizure susceptibility and brain levels of interleukins 1β and 6

Brain hyperexcitability in sleep apnea is believed to be provoked by hypoxemia, but sleep fragmentation can also play a significant role. Sleep fragmentation can trigger inflammatory mechanisms. The aim of this research was to investigate the effects of chronic sleep fragmentation on seizure susceptibility and brain cytokine profile. Chronic sleep fragmentation in male rats with implanted EEG electrodes was achieved by the treadmill method. Rats were randomized to: treadmill control (TC); activity control (AC) and sleep fragmentation (SF) group. Convulsive behavior was assessed 14 days later by seizure incidence, latency time and seizure severity during 30 min following lindane administration. The number and duration of EEG ictal periods were determined. Levels of IL-1β and IL-6 were measured in the animals' serum and brain structures (hippocampus, thalamus and cerebral cortex), in separate rat cohort that underwent the same fragmentation protocol except lindane administration. Incidence and severity of seizures were significantly increased, while latency was significantly decreased in SF+L compared with TC+L group. Seizure latency was also significantly decreased in SF+L compared to AC+L group. The number and duration of ictal periods were increased in the SF+L compared to the AC+L group. IL-1β was significantly increased in the thalamus, cortex and hippocampus in the SF compared to the AC and TC groups. IL-6 was statistically higher only in the cortex of SF animals, while in the thalamic or hippocampal tissue, no difference was observed between the groups. It could be concluded that fourteen-day sleep fragmentation increases seizure susceptibility in rats and modulates brain production of IL-1β and IL-6.

Brain hyperexcitability in sleep apnea is believed to be provoked by hypoxemia, but sleep fragmentation can also play a significant role. Sleep fragmentation can trigger inflammatory mechanisms. The aim of this research was to investigate the effects of chronic sleep fragmentation on seizure susceptibility and brain cytokine profile. Chronic sleep fragmentation in male rats with implanted EEG electrodes was achieved by the treadmill method. Rats were randomized to: treadmill control (TC); activity control (AC) and sleep fragmentation (SF) group. Convulsive behavior was assessed 14 days later by seizure incidence, latency time and seizure severity during 30 min following lindane administration. The number and duration of EEG ictal periods were determined. Levels of IL-1β and IL-6 were measured in the animals’ serum and brain structures (hippocampus, thalamus and cerebral cortex), in separate rat cohort that underwent the same fragmentation protocol except lindane administration. Incidence and severity of seizures were significantly increased, while latency was significantly decreased in SF+L compared with TC+L group. Seizure latency was also significantly decreased in SF+L compared to AC+L group. The number and duration of ictal periods were increased in the SF+L compared to the AC+L group. IL-1β was significantly increased in the thalamus, cortex and hippocampus in the SF compared to the AC and TC groups. IL-6 was statistically higher only in the cortex of SF animals, while in the thalamic or hippocampal tissue, no difference was observed between the groups. It could be concluded that fourteen-day sleep fragmentation increases seizure susceptibility in rats and modulates brain production of IL-1β and IL-6.

Hypertension in Polycystic Ovary Syndrome: Novel Insights

Polycystic ovary syndrome (PCOS) is a common endocrine disease in women during reproductive age. It was shown that PCOS women are with high risk for dyslipidemia, glucose intolerance, type 2 diabetes and metabolic syndrome. These factors are considered to represent traditional risk factors for the occurrence of cardiovascular disease. Observed increased risk for hypertension in PCOS women seems to be associated with insulin resistance and hyperinsulinemia. Both conditions interfere with the endothelium-dependent vasodilatation mechanisms causing vascular muscle wall hypertrophy. Obesity and insulin resistance are considered key factors for the alteration of blood pressure in PCOS women. Higher cardiovascular risk is implicated in PCOS with aging and its consequent association with both systolic and diastolic blood pressure. The elements of renin-angiotensin-aldosterone system (RAAS) have an impact on endothelial dysfunction as a marker of cardiovascular damage that could be modified is women with PCOS. Androgens and components of RAAS are involved in the process of atherogenesis in PCOS women. Therefore, it is hypothesized that spironolactone treatment could ameliorate endothelial dysfunction in PCOS women. Recently it was shown that telmisartan, angiotensin II receptor antagonist poses insulinsensitizing capacity to activate PPAR gamma and mediate favorable metabolic and reproductive effects in hypertensive PCOS women.

Alterations of medial prefrontal cortex bioelectrical activity in experimental model of isoprenaline-induced myocardial infarction

BACKGROUND

Clinical and animal studies have found that anxiety and depression are significantly more common after acute myocardial infarction (AMI). The medial prefrontal cortex (PFC) has a dual role: in higher brain functions and in cardiovascular control, making it a logical candidate for explaining the perceived bidirectional heart-brain connection. We used parallel Electrocardiography (ECG) and Electrocorticography (ECoG) registration to investigate AMI-induced changes in medial PFC bioelectrical activity in a rat model of AMI.

MATERIALS AND METHODS

Adult male Wistar albino rats were used in the study. Gold-plated recording electrodes were implanted over the frontal cortex for ECoG recording. ECG was recorded via two holter electrodes attached on the skin of the back fixed in place by a jacket. Induction of AMI was performed by isoprenaline (150 mg/kg, i.p.). ECoG and ECG signals were registered at baseline, during 3 hours after isoprenaline administration and at 24 hours after isoprenaline administration.

RESULTS

Significant increases of theta, alpha, and beta electroencephalographic (EEG) band power were observed in different time intervals after isoprenaline administration. Significant increase of theta band peak frequency was also observed during the first hour after isoprenaline administration. No statistically significant differences in band-power activity were found between the pre-isoprenaline measurements and 24 hours after administration.

CONCLUSION

Our results demonstrate significant increases in EEG band power of alpha beta and theta bands during isoprenaline-induced AMI model. These are the first findings to connect heart damage during isoprenaline- induced AMI to disturbances in the cortical bioelectrical activity.

Nonalcoholic Fatty Liver Disease in Patients with Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine disease in women during the reproductive period. True PCOS phenotype is prone to develop metabolic consequences during life. Obese PCOS women with insulin resistance are carrying a risk for developing type 2 diabetes, and influencing liver function by generating liver steatosis and nonalcoholic fatty liver disease (NAFLD). Moreover, serum testosterone of over 3 nmol/L is associated with at least two-fold higher risk for the development of NAFLD in PCOS women. Numerous genes involved in the pathogenesis of hyperandrogenism, insulin resistance and inflammation are associated with the development of NAFLD in PCOS women. Liver biopsy is not considered as the first line procedure for the diagnosis of liver damage in a prevalent condition as PCOS. Therefore, simple and reliable surrogate markers as serum aminotransferases levels or surrogate indexes (i.e. fatty liver index and NAFLD-fatty liver score) could be used for the assessment of fatty liver in PCOS women. First line therapeutic approach for NAFLD in PCOS includes a change in lifestyle that implies dietary regiment and physical activity but without well-defined protocols. Second line therapy considers addition of drugs on the established lifestyle change. Metformin remains the drug of choice for reduction of insulin resistance and liver enzymes level. Liraglutide, glucagon-like peptide-1 receptor agonists, showed favorable effects on the reduction of liver fat content and visceral adipose tissue in overweight women with PCOS. Current review analyzes the impact of metabolic risk factors, diagnostic approach and management options on NAFLD in women with PCOS.

The effects of dietary methionine restriction on the function and metabolic reprogramming in the liver and brain - implications for longevity

Methionine is an essential sulphur-containing amino acid involved in protein synthesis, regulation of protein function and methylation reactions. Dietary methionine restriction (0.12-0.17% methionine in food) extends the life span of various animal species and delays the onset of aging-associated diseases and cancers. In the liver, methionine restriction attenuates steatosis and delays the development of non-alcoholic steatohepatitis due to antioxidative action and metabolic reprogramming. The limited intake of methionine stimulates the fatty acid oxidation in the liver and the export of lipoproteins as well as inhibits de novo lipogenesis. These effects are mediated by various signaling pathways and effector molecules, including sirtuins, growth hormone/insulin-like growth factor-1 axis, sterol regulatory element binding proteins, adenosine monophosphate-dependent kinase and general control nonderepressible 2 pathway. Additionally, methionine restriction stimulates the synthesis of fibroblast growth factor-21 in the liver, which increases the insulin sensitivity of peripheral tissues. In the brain, methionine restriction delays the onset of neurodegenerative diseases and increases the resistance to various forms of stress through antioxidative effects and alterations in lipid composition. This review aimed to summarize the morphological, functional and molecular changes in the liver and brain caused by the methionine restriction, with possible implications in the prolongation of maximal life span.

The effects of L-cysteine and N-acetyl-L-cysteine on homocysteine metabolism and haemostatic markers, and on cardiac and aortic histology in subchronically methionine-treated Wistar male rats

Methionine is the precursor of homocysteine, a sulfur amino acid intermediate in the methylation and transsulfuration pathways; methionine-rich diets were used to induce hyperhomocysteinemia, and cardiovascular pathology was often observed. Other sulfur amino acids interfere with this metabolism, i.e., L-cysteine (Cys) and N-aceyl-L-cysteine (NAC), and probably also affect cardiovascular system. Their effects are controversial due to their ability to act both as anti- or pro-oxidant. Thus, this study aimed to elucidate their influence on levels of homocysteine, folate and vitamin B12, levels of different haemostatic parameters (fibrinogen, D-dimer, vWF Ag, vWF Ac) in rat serum or plasma as well as their effects on cardiac and aortic tissue histology in subchronically methionine-treated rats. Wistar albino rats were divided into 4 experimental groups: (a) control group (0.9% sodium chloride 0.1-0.2 mL/day) (n = 10) (K); (b) DL-methionine (0.8 mmol/kg/bw/day) (n = 10) (M); (c) DL-methionine (0.8 mmol/kg/bw/day) + L-cysteine (7 mg/kg/bw/day) (n = 8) (C); (d) DL-methionine (0.8 mmol/ kg/bw/day) + N-acetyl-L-cysteine (50 mg/kg/bw/day) (n = 8) (N). All substances were applied i.p., treatment duration 3 weeks. Lower levels of vitamin B12 in all the groups were found. Folate was reduced only in N group. Decreased fibrinogen was noted in C and N groups and increased D-dimer only in C. VWF activity was reduced in M and C groups. Deleterious effects in heart were observed, especially after Cys and NAC application. Aortic tissue remained unchanged. In conclusion, it could be said that sulfur amino acids have the significant impact on cardiovascular system in subchronically methionine-treated rats. This study points out the relevance of their complex interactions and deleterious effects mediated by either direct influence or procoagulant properties.

Novel Assessment Tool For Coronary Artery Disease Severity During Screening Mammography

Breast arterial calcifications (BACs) are common findings on mammography which are associated with an increased risk of the coronary artery disease (CAD). Our aim in the current study was to design measurement instruments of CAD prediction, with or without BACs, and its discriminatory validity in the diagnosis of CAD (expressed by Syntax score) in women. This was observational, prospective study in the women cohort which underwent mammography and angiography. In this study we have demonstrated that the total 'The Breast Arterial Calcification and Coronary Artery Disease Scale' (BACCADS) was good additional diagnostic tool for detection of patients with severe CAD.

The correlation of SYNTAX score by coronary angiography with breast arterial calcification by digital mammography

AIM

To evaluate the hypothesis that breast arterial calcification (BAC) may predict coronary artery disease (CAD) severity.

MATERIALS AND METHODS

The study comprised 102 women >45 years (mean age 62±8 years) referred for digital mammography after coronary angiography. BAC was assessed using the Likert scale and CAD severity was assessed using the SYNTAX (SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery trial) score.

RESULTS

In comparison to the low SYNTAX score group (≤22) patients with a intermediate-to-high SYNTAX score (>22) were older (p=0.001), they more often had hypercholesterolaemia (p<0.001), diabetes (p=0.021), and a history of smoking (p=0.048). They also had a statistically higher level of fasting blood glucose (p<0.001), glycated haemoglobin (HbA1C; p<0.001), triglycerides (p=0.002), fibrinogen (p=0.001), whereas high-density lipoprotein (HDLc) was lower than in the group with a SYNTAX score ≤22 (p=0.005). BAC was significantly higher in patients with a SYNTAX score >22 (p<0.001). At multivariate analysis, BAC (odds ratio [OR] 34.24, 95% confidence interval [CI]: 8.05-145.7, p<0.001), hypercholesterolaemia (OR 22.65, 95% CI: 4.18-122.81, p<0.001) and fibrinogen (OR 2.55, 95% CI: 1.28-5.07, p=0.008) were independent predictive factors for patients with intermediate-to-high SYNTAX score.

CONCLUSIONS

In women >45 years, there was a significant correlation between the severity of CAD as evaluated by the SYNTAX score and BAC as evaluated by the Likert scale. BAC, hypercholesterolaemia, and fibrinogen may be used as an additional diagnostic tool to predict the presence and severity of CAD.

The Influence of Finasteride on Mean and Relative Spectral Density of EEG Bands in Rat Model of Thioacetamide-Induced Hepatic Encephalopathy

Liver failure is associated with a neuropsychiatric syndrome, known as hepatic encephalopathy (HE). Finasteride, inhibitor of neurosteroid synthesis, may improve the course of HE. The aim of our study was to investigate the influence of finasteride on mean and relative power density of EEG bands, determined by spectral analysis, in rat model of thioacetamide-induced HE. Male Wistar rats were divided into groups: (1) control; (2) thioacetamide-treated group, TAA (900 mg/kg); (3) finasteride-treated group, FIN (150 mg/kg); and (4) group treated with finasteride (150 mg/kg) and thioacetamide (900 mg/kg), FIN + TAA. Daily doses of FIN (50 mg/kg) and TAA (300 mg/kg) were administered during 3 subsequent days, and in FIN + TAA group FIN was administered 2 h before every dose of TAA. EEG was recorded 22-24 h after treatment and analyzed by fast Fourier transformation. While TAA did not induce significant changes in the beta band, mean and relative power in this band were significantly higher in FIN + TAA versus control group (p < 0.01). TAA caused a significant decline in mean power in alpha, theta, and delta band, and in FIN + TAA group the mean power in these bands was significantly higher compared with control. While in TAA group relative power was significantly decreased in theta (p < 0.01) and increased in delta band (p < 0.01) versus control, the opposite changes were found in FIN + TAA group: an increase in theta (p < 0.01) and a decrease in delta relative power (p < 0.01). In this study, finasteride pretreatment caused EEG changes that correspond to mild TAA-induced HE.

Multidisciplinary approach to nitric oxide signaling: Focus on the gastrointestinal and the central nervous system

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Finasteride improves motor, EEG, and cellular changes in rat brain in thioacetamide-induced hepatic encephalopathy

Neurosteroids are involved in the pathogenesis of hepatic encephalopathy (HE). This study evaluated the effects of finasteride, inhibitor of neurosteroid synthesis, on motor, EEG, and cellular changes in rat brain in thioacetamide-induced HE. Male Wistar rats were divided into the following groups: 1) control; 2) thioacetamide-treated group, TAA (300 mg·kg(-1)·day(-1)); 3) finasteride-treated group, FIN (50 mg·kg(-1)·day(-1)); and 4) group treated with FIN and TAA (FIN + TAA). Daily doses of TAA and FIN were administered in three subsequent days intraperitoneally, and in the FIN + TAA group FIN was administered 2 h before every dose of TAA. Motor and reflex activity was determined at 0, 2, 4, 6, and 24 h, whereas EEG activity was registered about 24 h after treatment. The expressions of neuronal (NeuN), astrocytic [glial fibrilary acidic protein (GFAP)], microglial (Iba1), and oligodendrocyte (myelin oligodendrocyte glycoprotein) marker were determined 24 h after treatment. While TAA decreased all tests, FIN pretreatment (FIN + TAA) significantly improved equilibrium, placement test, auditory startle, head shake reflex, motor activity, and exploratory behavior vs. the TAA group. Vital reflexes (withdrawal, grasping, righting and corneal reflex) together with mean EEG voltage were significantly higher (P < 0.01) in the FIN + TAA vs. the TAA group. Hippocampal NeuN expression was significantly lower in TAA vs. control (P < 0.05). Cortical Iba1 expression was significantly higher in experimental groups vs. control (P < 0.05), whereas hippocampal GFAP expression was increased in TAA and decreased in the FIN + TAA group vs. control (P < 0.05). Finasteride improves motor and EEG changes in TAA-induced HE and completely prevents the development of hepatic coma.

Homocysteine thiolactone-induced seizures in adult rats are aggravated by inhibition of inducible nitric oxide synthase

Homocysteine and its metabolites (homocysteine thiolactone (HT)) induce seizures via different but still not well-known mechanisms. The role of nitric oxide (NO) in epileptogenesis is highly contradictory and depends on, among other factors, the source of NO production. The aim of the present study was to examine the effects of aminoguanidine, selective inhibitor of inducible NO synthase (iNOS), on HT-induced seizures. Aminoguanidine (50, 75, and 100 mg/kg, intraperitoneally (i.p.)) was injected to rats 30 min prior to inducing HT (5.5 mmol/kg, i.p.). Seizure behavior was assessed by seizure incidence, latency time to first seizure onset, number of seizure episodes, and their severity during observational period of 90 min. Number and duration of spike and wave discharges (SWDs) were determined in electroencephalogram (EEG). Seizure latency time was significantly shortened, while seizure incidence, number, and duration of HT-induced SWD in EEG significantly increased in rats receiving aminoguanidine 100 mg/kg before subconvulsive dose of HT. Aminoguanidine in a dose-dependent manner also significantly increased the number of seizure episodes induced by HT and their severity. It could be concluded that iNOS inhibitor (aminoguanidine) markedly aggravates behavioral and EEG manifestations of HT-induced seizures in rats, showing functional involvement of iNOS in homocysteine convulsive mechanisms.

Ontogenetic influence on rat susceptibility to lindane seizure after pretreatment with phencyclidine

The aim of the study was to determine the effects of early postnatal PCP treatment on the sensitivity of pubertal and adult rats to lindane proepileptogenic effects. Rat pups were treated with NaCl (0.9%) or PCP (10 mg/kg) at postnatal days 2, 6, 9 and 12. One control (NaCl-35) and one experimental (PCP-35) group have received lindane (4 mg/kg) at postnatal day 35, while others received lindane at postnatal day 65 (NaCl-65 and PCP-65). One week prior to lindane treatment three gold-plated EEG electrodes were implanted. Pubertal rats had significantly shorter latency time. After lindane, a prompt increase in power spectral density seen in PCP-treated groups vs. control was evident earlier in PCP-65 rats. The theta waves were significantly increased in PCP-35 and alpha rhythm in PCP-65 rats, when compared with corresponding controls. Postnatal PCP treatment increases the synchronization of brain electrical activity, thus contributing to the increased susceptibility to lindane.

Paradoxical sleep deprivation potentiates epilepsy induced by homocysteine thiolactone in adult rats

There is an intriguing and still poorly understood relationship between sleep deprivation and epilepsy. It has recently been shown that paradoxical sleep deprivation decreases levels of homocysteine, an amino acid involved together with its thiolactone metabolite in epileptogenesis. The aim of the present study was to investigate the effects of paradoxical sleep deprivation on homocysteine thiolactone (H)-induced seizures in rats, a model of generalized seizures. Selective deprivation of paradoxical sleep in adult male Wistar rats was achieved by the platform method. Animals with implanted electrodes for electroencephalogram (EEG) registration were assigned to appropriate experimental conditions (dry cage for control, large platform for stress control and small platform for paradoxical sleep deprivation) and 72 h later were intraperitoneally treated with either H (5.5 mmol/kg) or saline (0.9% NaCl). This study showed that paradoxical sleep deprivation increased the incidence and number of H-induced seizure episodes, shortened latency time to seizures and led to significant rates of lethality after H administration, but without effect on the seizure severity. Paradoxical sleep deprivation increased the number and duration of spikes-and-wave discharges, while decreased latency to its appearance in EEG. Judging by the behavioral and EEG findings, it could be concluded that paradoxical sleep deprivation can provoke the expression of factors that can potentiate H-induced seizures in adult rats.

Spectral analysis of thioacetamide-induced electroencephalographic changes in rats

Thioacetamide (TAA) is widely used as a model of hepatic encephalopathy (HE). The aim of our study was to investigate the effects of TAA on electroencephalographic (EEG) changes in rats and to compare them with human HE. Male Wistar rats were divided into groups: (1) saline-treated group and (2) TAA-treated groups: TAA300 (300 mg/kg), TAA600 (600 mg/kg), and TAA900 (900 mg/kg). Daily dose of TAA (300 mg/kg) was administered intraperitoneally once (TAA300), twice (TAA600), or thrice (TAA900) in subsequent days. EEG changes were recorded about 24 h after the last dose of TAA. Absolute and relative power density in alpha bands were significantly higher in TAA300 versus control group. In TAA300, absolute beta power density was higher and relative beta power density was lower versus control group. Absolute alpha, theta, delta, and relative theta power were significantly lower, while relative power in delta band was significantly higher in TAA900 versus control group ( p < 0.01). In conclusion, decrease in EEG voltage with an increase in delta relative power, which correspond to the EEG manifestations of severe HE in humans, was observed in TAA900 group. Electrical activity in TAA300 group correlates with mild HE in humans.

Behavioral and electroencephalographic manifestations of thioacetamide-induced encephalopathy in rats

The aim of our study was to investigate the behavioral and electroencephalographic manifestations of thioacetamide-induced encephalopathy in rats. Male Wistar rats were divided among (i) control, saline-treated, and (ii) thioacetamide-treated groups (TAA(300) (300 mg/kg body mass); TAA(600) (600 mg/kg); and TAA(900) (900 mg/kg)). The daily dose of thioacetamide (300 mg/kg) was administered intraperitoneally once (TAA(300)), twice (TAA(600)), or 3 times (TAA(900)), on subsequent days. Behavioral manifestations were determined at 0, 2, 4, 6, and 24 h, while electroencephalographic changes were recorded 22-24 h after the last dose. General motor activity and exploratory behavior, as well as head shake, auditory startle reflex, placement, and equlibrium tests were diminished in the TAA(600) and TAA(900) groups compared with the control, and were absent in the TAA(900) group 24 h after treatment. Corneal, withdrawal, grasping, and righting reflexes were significantly diminished in the TAA(900) group compared with the control. Mean electroencephalographic power spectra density was significantly higher in TAA(300) and TAA(600) and lower in the TAA(900) group by comparison with the control. Only a score of 3 (mean dominant frequency ≤ 7.3 Hz and δ relative power ≥ 45%) was observed in the TAA(900) group. Thioacetamide induces encephalopathy in rats in a dose-dependent manner. A dose of 900 mg/kg TAA may be used as a suitable model of all stages of hepatic encephalopathy.