Atherogenic Impact of Homocysteine: Can HMG-CoA Reductase Inhibitors Additionally Influence Hyperhomocysteinaemia?

The strong association among the risk of coronary artery diseases (CAD), high levels of LDL-C and low levels of HDLC is well established. Hyperhomocysteinaemia (HHcy) is an independent risk factor for cardiovascular disease (CVD) and causes endothelial dysfunction, a hallmark of atherosclerosis. In this study, we ascertained the influence of statins on the atherogenic index, as an indicator and a significant adjunct for predicting atherosclerosis in hyperhomocysteinaemic male Wistar albino rats. For 4 weeks, the animals were fed with one of the following diets (Mucedola SRL., Milan, Italy): standard rodent chow; a diet enriched in methionine with no deficiency in B vitamins or a diet enriched in methio-nine and deficient in B vitamins. The animals were simultaneously exposed to a pharmacology treatment with atorvastatin at dose of 3 mg/kg/day i.p. or simvastatin, at dose of 5 mg/kg/day i.p. We measured weight gain, food intake, and FER and determined the concentrations of biochemical parameters of dyslipidaemia (TC, TGs, LDL-C, VLDL-C, and HDL-C), AI, and CRR. A histopathological examination was conducted on portions of the right and left liver lobes from each animal. A connection between Hhcy and dyslipidaemia was indicated by the findings of biochemical and histological analyses, suggesting that Hhcy was a pro-atherogenic state. An improvement in the lipid profile along with a decrease in the atherogenic index by statins suggests that atorvastatin and simvastatin could be useful antiatherogenic agents, with protective activities during hyperhomocysteinaemia.

Oxidative Stress Parameters after Abdominal Hysterectomy and Their Relationships with Quality of Recovery

Study aimed to investigate relationship between oxidative stress markers and postoperative recovery in woman after abdominal hysterectomy, as well as to test the hypothesis that different analgesics differently influence redox status.

The quality of recovery was evaluated with a QoR-40 questionnaire in fifty-one patients who underwent abdominal hysterectomy, preoperatively and on the 1st, 2nd, 3rd postoperative days (POD1,2,3). Blood samples were collected at baseline (T0), 3 (T1), 24 (T2), 48 (T3) and 72 (T4) hours after surgery. Oxidative stress markers concentrations (TBARS, NO2 −, H2O2, O2 − ) as well as antioxidative enzymes (SOD, CAT, and GSH) were analyzed.

QoR-40 total score significantly declined on POD1 and POD2 and returned to baseline levels on POD3 (p<0.001). H2O2 levels significantly decreased from T0 to T3 and then, increased at T4 (p=0,011). Changes of TBARS and H2O2 from T0 to T3 showed significant and negative correlation (r=−0.303, p=0.046). There was no significant correlation between QoR-40 total score and any parameter of oxidative stress response (p>0.05). Changes in TBARS levels from T0 to T3 were statistically significant between the study subgroups primarily due to increase of the concentrations in patients receiving paracetamol (p=0.031). Patients age, duration of surgery and cigarette smoking status showed significant influcences on and association with some oxidative stress response markers (TBARS, O2 −, CAT) (p<0.05).

Women who underwent hysterectomy had significant changes of H2O2 and TBARS activity however, those changes were not associated with changes of QoR-40 total scores during recovery.

Olanzapine - Focus on the Cardiometabolic Side Effects

In this article, we review the recent findings concerning weight gain, diabetes mellitus (DM), hyperlipidemia, cardiovascular side effects in patients receiving olanzapine. It will consider the OLZ is associated with an increase in metabolic syndrome or cardiovascular events, and knowledge of these risks is crucial for further monitoring of patients with OLZ-treatment. Although it is one of the most commonly prescribed and effective AATPs, olanzapine causes the most weight gain and metabolic impairments in humans. As noted with glucose abnormalities and antipsychotics, olanzapine has the greatest propensity for causing proatherogenic hyperlipidemia. The mechanism of dyslipidemia with OLZ is poorly understood, but OLZ has been shown to increase lipogenesis, reduce lipolysis, and enhance the antilipolytic effects of insulin in adipocytes. Olanzapine can induce cardiomyopathy in selected patients.

Taken together, all mentioned data indicate that interventions aimed at the amelioration of obesity and cardiovascular illness need to be as multipronged and complex as the contributing psychosocial, behavioural, and biological factors that make obesity and cardiovascular illness more likely in patients with severe mental illness, including schizophrenia.

The Effects of Chronic Administration of Cisplatin on Oxidative Stress in the Isolated Rat Heart

Taken into consideration that molecular and cellular mechanisms involved in cardiotoxicity are still not clear the aim of this study was to compare the production of oxidative stress parameters in the isolated rat heart between animals chronically treated with cisplatin and saline. The hearts of male Wistar albino rats (n = 24, 12 per group, age 8 weeks, body mass 250±50 g) were excised and perfused according to the Langendorff technique at gradually increased coronary perfusion pressures (40-120 cm H2O). We followed the production of superoxide anion radicals, hydrogen peroxide, and nitrites and also index of lipid peroxidation during the changes of coronary perfusion pressure (CPP) (from 40 to 120 cm H2O) in coronary venous effluent. Modifications CPP were performed in order to determined if oxidative stress is involved in coronary endothelium response in conditions of hypoxia (lower than 60 cm H2O) and hyperoxia (higher than 80 cm H2O).

Based on the results of this research we can conclude that with enhancement of CPP the values of oxidative stress statistically increased. However, this increment is more prominent in control group as a result of preserved endothelium and its more powerful response to hyperoxia. On the other hand, damaged endothelium of cisplatin-treated animals had weaker response to hyperoxia, and also lower antioxidant capacity.

The Effects of Methionine-Enriched and Vitamins (Folate, Pyridoxine and Cobalamine)-Deficient Diet on Exploratory Activity in Rats - A Brief Report

The aim of this study was to evaluate the impact of increased homocysteine levels induced by methionine nutritional overload (twice as standard) and deficiency of the vitamins folate, pyridoxine and cobalamine, which plays an important role in homocysteine metabolism in anxiety-related behaviour, expressed by means of exploratory activity in rats. Twenty-three male Wistar albino rats (4 weeks old, 100±15 g body weight) were divided into three groups: control (n=8), methionine-enriched (Meth+, 7.7 g of methionine/kg chow, n=7) and methionine-enriched vitamin-deficient (Meth+Vit-, 7.7 g of methionine/ kg chow, deficient in folate, pyridoxine and cobalamine - 0.08, 0.01 and 0.01 mg/kg, n=8). All animals had free access to food and water for 30 days. Behavioural testing was performed using the elevated plus maze (EPM) test. Standard parameters for vertical exploratory activity, the number of rearings and the number of head-dippings, as well as the total exploratory activity (summarizing overall exploratory activity in the EPM) were significantly reduced following 30 days of methionine nutritional overload (p<0.05, p<0.05 and p<0.01, respectively). A methionine-enriched diet coupled with a reduction in some B vitamins resulted in a more pronounced decline in exploratory drive observed in the EPM test compared to the control (p<0.01). The decline in total exploratory activity associated with vitamin deficiency was significant compared to the Meth+ group (p<0.05). The results of this study highlight the important role of homocysteine in the modulation of exploratory activity in rats. Decreased exploratory drive induced by both a methionine-enriched and vitamin-deficient diet could be attributed to an anxiogenic effect of hyperhomocysteinemia.

Тhe Impact Of Positive Acceleration (+Gz) on Antioxidant Capacity and Histopathological Alterations in Different Organs and Tissues in Rats

Since the early 1940s, a significant amount of research has been conducted to describe the impact of the high-G acceleration on the cardiovascular system. The objective of the present study was to examine the role of the antioxidant enzyme system under biodynamic stress in the liver, heart and gastric mucosa in response to high-magnitude +Gz exposure in a rat model. Twenty adult male Wistar albino rats (10 rats per group; 9-11 weeks old, 200-250 g b.w.) were divided into the following two groups: control and G (exposed to a biodynamic stress model under positive (+7 Gz) acceleration for 40 s). The influence of acute biodynamic stress on pro-oxidative parameters in the rat liver (xanthine oxidase (XOD), catalase (CAT), peroxidase (Px), glutathione peroxidase (GSH-Px), total content of glutathione (GSH), lipid peroxidation (LPx)) and on histopathological alterations in the liver, cardiac muscle and gastric mucosa was examined. Biodynamic stress resulting from positive (+7 Gz) acceleration resulted in a highly statistically signifi cant increase of CAT GSH-Px activity compared to the control group. The LPx levels were significantly decreased, but the GSH contents and the activities of other enzymes were not significantly changed. Significant microscopic changes in the liver, heart and gastric mucosa were observed in the G group. These results clearly indicate that +Gz acceleration alters biochemical systems. These alterations in cellular processes may be mediated by influences of hypoxia or ischaemia via changes in the antioxidant capacity.

Estradiol decreases blood pressure in association with redox regulation in preeclampsia

In this study, we tested a hypothesis that a short-term estradiol therapy may reduce blood pressure in preeclampsia by modulating plasma oxidative stress. The intramuscular injections of 10 mg 17-beta-estradiol were prescribed to preeclamptic pregnant women during the 3-day therapy before a labor induction. The analyses of mean arterial pressure (MAP), serum estradiol concentrations, plasma superoxide anion (O₂.), hydrogen peroxide (H₂O₂), nitrites (NO₂^-), and peroxynitrite (ONOO^-) were conducted before and during the therapy. We found that the plasma concentrations of oxidative stress markers, such as O₂^- and H₂O₂, are higher in preeclampsia and positively correlated with the MAP value. Moreover, it was shown that the plasma concentration of NO₂^- as an indicator of NO levels is higher in preeclampsia. A short-term intramuscular application of estradiol decreases the MAP value and the plasma concentration of O^.-, H₂O₂, NO₂^-, and ONOO^- in preeclampsia. A positive correlation between the decrease of MAP values and the decrease of plasma concentrations of O₂^-, H₂O₂, and ONOO^- was found in preeclampsia during a short-term estradiol therapy. We conclude that the short-term estradiol therapy decreases the MAP value in preeclampsia by modulating the plasma oxidative stress. We speculate that the estradiol metabolism in preeclampsia is an important mechanism that contributes to vascular dysfunction.

The Effects of Chronic Administration of Cisplatin on Oxidative Stress in the Isolated Rat Heart

Taken into consideration that molecular and cellular mechanisms involved in cardiotoxicity are still not clear the aim of this study was to compare the production of oxidative stress parameters in the isolated rat heart between animals chronically treated with cisplatin and saline. Th e hearts of male Wistar albino rats (n = 24, 12 per group, age 8 weeks, body mass 250±50 g) were excised and perfused according to the Langendorff technique at gradually increased coronary perfusion pressures (40-120 cmH2O). We followed the production of superoxide anion radicals, hydrogen peroxide, and nitrites and also index of lipid peroxidation during the changes of coronary perfusion pressure (CPP) (from 40 to 120 cm H2O) in coronary venous effluent. Modifications CPP were performed in order to determined if oxidative stress is involved in coronary endothelium response in conditions of hypoxia (lower than 60 cm H2O) and hyperoxia (higher than 80 cm H2O). Based on the results of this research we can conclude that with enhancement of CPP the values of oxidative stress statistically increased. However, this increment is more prominent in control group as a result of preserved endothelium and its more powerful response to hyperoxia. On the other hand, damaged endothelium of cisplatin-treated animals had weaker response to hyperoxia, and also lower antioxidant capacity.

Mesenchymal stem cells protect from acute liver injury by attenuating hepatotoxicity of liver natural killer T cells in an inducible nitric oxide synthase- and indoleamine 2,3-dioxygenase-dependent manner

The effects of mesenchymal stem cells (MSCs) on the phenotype and function of natural killer T (NKT) cells is not understood. We used concanavalin A (Con A) and α-galactosylceramide (α-GalCer)-induced liver injury to evaluate the effects of MSCs on NKT-dependent hepatotoxicity. Mouse MSCs (mMSCs) significantly reduced Con A- and α-GalCer-mediated hepatitis in C57Bl/6 mice, as demonstrated by histopathological and biochemical analysis, attenuated the influx of inflammatory [T-bet⁺ , tumour necrosis factor-α (TNF-α), interferon-γ (IFN-γ)-producing and GATA3⁺ , interleukin-4 (IL-4)-producing] liver NKT cells and downregulated TNF-α, IFN-γ and IL-4 levels in the sera. The liver NKT cells cultured in vitro with mMSCs produced lower amounts of inflammatory cytokines (TNF-α, IFN-γ, IL-4) and higher amounts of immunosuppressive IL-10 upon α-GalCer stimulation. mMSC treatment attenuated expression of apoptosis-inducing ligands on liver NKT cells and suppressed the expression of pro-apoptotic genes in the livers of α-GalCer-treated mice. mMSCs reduced the cytotoxicity of liver NKT cells against hepatocytes in vitro. The presence of 1-methyl-dl-tryptophan, a specific inhibitor of indoleamine 2,3-dioxygenase (IDO), or l-N^G -monomethyl arginine citrate, a specific inhibitor of inducible nitric oxide synthase (iNOS), in mMSC-conditioned medium injected into α-GalCer-treated mice, counteracted the hepatoprotective effect of mMSCs in vivo and restored pro-inflammatory cytokine production and cytotoxicity of NKT cells in vitro. Human MSCs attenuated the production of inflammatory cytokines in α-GalCer-stimulated human peripheral blood mononuclear cells in an iNOS- and IDO-dependent manner and reduced their cytotoxicity against HepG2 cells. In conclusion, MSCs protect from acute liver injury by attenuating the cytotoxicity and capacity of liver NKT cells to produce inflammatory cytokines in an iNOS- and IDO-dependent manner.

Modulation of N-methyl-d-aspartate receptors in isolated rat heart

Considering the limited data on the role of NMDA-Rs in the cardiovascular system, the aim of the present study was to examine the effects of NMDA and DL-Hcy TLHC, alone and in combination with glycine, memantine, and ifenprodil, in the isolated rat heart. The hearts of Wistar albino rats were retrogradely perfused according to the Langendorff technique at a constant perfusion pressure. The experimental protocol for all experimental groups included the stabilization period, application of estimated substance for 5 min, followed by a washout period of 10 min. Using a sensor placed in the left ventricle, we registered the following parameters of myocardial function: dp/dt_max, dp/dt_min, SLVP, DVLP, HR; CF was measured using flowmetry). We estimated the following oxidative stress biomarkers in the coronary venous effluent using spectrophotometry: TBARS, NO₂^-, O₂^-, and H₂O₂. NMDA alone did not induce any change in any of the observed parameters, while DL-Hcy TLHC alone, as well as a combined application of NMDA and DL-Hcy TLHC with glycine, induced a reduction of most cardiodynamic parameters. Memantine and ifenprodil induced a reduction of cardiodynamic parameters and CF, as well as some oxidative stress biomarkers.

The acute effects of different spironolactone doses on cardiac function in streptozotocin-induced diabetic rats

Currently, cardiovascular diseases are the leading cause of global mortality, while diabetes mellitus remains an important cause of cardiovascular morbidity. A recent study showed that patients with diabetes mellitus treated with mineralocorticoid receptor antagonists have improved coronary microvascular function, leading to improved diastolic dysfunction. In this study, we evaluated the influence of acute administration of spironolactone on myocardial function in rats with streptozotocin-induced diabetes mellitus, with special emphasis on cardiodynamic parameters in diabetic rat hearts. The present study was carried out on 40 adult male Wistar albino rats (8 weeks old). Rats were randomly divided into 4 groups (10 animals per group): healthy rats treated with 0.1 μmol/L of spironolactone, diabetic rats treated with 0.1 μmol/L of spironolactone, healthy rats treated with 3 μmol/L of spironolactone, and diabetic rats treated with 3 μmol/L of spironolactone. Different, dose-dependent, acute responses of spironolactone treatment on isolated, working diabetic and healthy rat heart were observed in our study. In healthy rats, better systolic function was achieved with higher spironolactone dose, while in diabetic rats, similar effects of low and high spironolactone dose were observed.

Effects of atorvastatin and simvastatin on oxidative stress in diet-induced hyperhomocysteinemia in Wistar albino rats: a comparative study

Considering the well-known antioxidant properties of statins, it seems important to assess their impact on major markers of oxidative stress (superoxide anion radical, nitric oxide, and index of lipid peroxidation) to compare the antioxidative potentials of atorvastatin and simvastatin during the different degrees of hyperhomocysteinemia (HHcy) in rats. This study was conducted on adult male Wistar albino rats (n = 90; 4 weeks old; 100 ± 15 g body mass) in which HHcy was achieved by dietary manipulation. For 4 weeks, the animals were fed with one of the following diets: standard rodent chow, diet enriched in methionine with no deficiency in B vitamins (folic acid, B6, and B12), or diet enriched in methionine and deficient in B vitamins (folic acid, B6, and B12). At the same time, animals were treated with atorvastatin at doses of 3 mg/kg/day i.p. or simvastatin at doses of 5 mg/kg/day i.p. Levels of superoxide anion radical and TBARS were significantly decreased by administration of simvastatin in normal and high-homocysteine (Hcy) groups (p < 0.05). At 4 weeks after feeding with purified diets, the concentrations of the GSH, CAT, and SOD antioxidants were significantly affected among all groups (p < 0.05). Our results indicated that statin therapy had variable effects on the redox status in hyperhomocysteinemic rats, and simvastatin demonstrated stronger antioxidant effects than did atorvastatin.

The Influence of Different Types of Physical Activity on The Redox Status of Scuba Divers

The effect of scuba diving on ROS production and oxidative stress compared to that of other recreational activities is still poorly understood. The aim of this study was to assess the influence of different types of physical activity on the redox status of scuba divers by testing the pro- and anti-oxidative parameters immediately before and after different types of physical load. The prevalence study included 10 professional police divers. All examinees were male, 32 ± 5.1 years of age, well-trained, and with a minimum of five to a maximum of 20 years of diving experience. The study was divided into three experimental protocols: 1) an exercise test (at atmospheric pressure), 2) an at sea dive (30 meters for 30 minutes), and 3) a dive into river current (10 meters for 30 minutes). Immediately before and after the load test of the divers at atmospheric pressure and immediately before and after the dive, blood samples were taken to determine the values of the following pro-oxidant markers: O2 −, H2O2, NO2 − and TBARS, as well as antioxidant enzymes (SOD and CAT). A comparison of the results before and after physical activity for all three protocols revealed a significant increase in values for NO2 −, O2 −, H2O2 and CAT after physical activity. It can be concluded that the values of all oxidative stress markers depend on the season of the year in which the research is conducted or on the frequency of dives and degree of physical exertion during this period of the year.

Interleukin-6 as possible early marker of stress response after femoral fracture

Bone fracture healing is a complex process which at best results in full recovery of function and structure of injured bone tissue, but all the mechanisms involved in this process, and their mutual interaction, are not fully understood. Despite advancement of surgical procedures, this type of fractures is still a major public health concern. In the last few decades, a lot of attention is focused on the oxygen-free radicals and inflammatory response markers as important factors of skeletal injury. Thus, the aim of the present study was to follow the changes in redox balance and inflammatory response in elderly patients with femoral fractures during the earliest stages of fracture healing, by measuring the values of the observed markers immediately after fracture, as well as the first, third, and seventh postoperative day. Present study was performed on a group of 65 elderly patients with femoral neck fractures, recruited from the Orthopedic Clinic, Clinical Centre Kragujevac in the period from February to May 2015. Redox status was measured spectrophotometrically and evaluated by measuring the levels of index of lipid peroxidation (measured as TBARS), nitrite (NO₂^-), superoxide anion radical (O₂^-), and hydrogen peroxide (H₂O₂) in plasma, while activities of corresponding antioxidative enzymes, catalase (CAT), superoxide dismutase (SOD), and reduced glutathione (GSH) were measured in erythrocytes. The cytokine concentrations of interleukin (IL)-6 and tumor necrosis factor (TNF)-α were determined in plasma, using ELISA assays specific for human cytokines. Our study showed that redox status and TNF-α in elderly patients with femoral fractures did not show statistically significant changes during the early phase of fracture healing. On the other hand, IL-6 increased statistically in first day after intervention. This preliminary study has shown our observations, and we hope that these results may help in better understanding mechanisms which are included at fracture healing. More importantly, this study attempted to create a platform for further research.

Redox Status in Patients with Femoral Neck Fractures

The femur transfers the body weight from the pelvic bone to the shinbone. Femur fractures are a significant cause of morbidity and mortality among the group of locomotor apparatus injuries, especially in the elderly population. Considering that oxidative stress occurs as a result of increased production of free radicals that damage cell function and cause numerous pathological conditions and diseases, the aim of this study was to investigate oxidative stress parameters in older patients with femoral neck fractures. This clinical study included 70 patients, of which 35 had femoral neck fractures (26 males and 9 females), while the other half of the patients formed the matched control group. Markers of oxidative stress (NO2 −, TBARS, H2O2 and O2 -) and anti-oxidative enzymes (SOD, CAT, and GSH) were measured. Results showed that the levels of O2 - increased, while levels of NO2 -, H2O2 and all the antioxidative enzymes decreased in patients with femoral neck fractures. These findings indicate that fractures cause oxidative stress, probably because of the reduced activity of osteoblasts and the increased activity of osteoclasts.

Proinsulin multi-peptide immunotherapy induces antigen-specific regulatory T cells and limits autoimmunity in a humanized model

Peptide immunotherapy (PIT) is a targeted therapeutic approach, involving administration of disease-associated peptides, with the aim of restoring antigen-specific immunological tolerance without generalized immunosuppression. In type 1 diabetes, proinsulin is a primary antigen targeted by the autoimmune response, and is therefore a strong candidate for exploitation via PIT in this setting. To elucidate the optimal conditions for proinsulin-based PIT and explore mechanisms of action, we developed a preclinical model of proinsulin autoimmunity in a humanized HLA-DRB1*0401 transgenic HLA-DR4 Tg mouse. Once proinsulin-specific tolerance is broken, HLA-DR4 Tg mice develop autoinflammatory responses, including proinsulin-specific T cell proliferation, interferon (IFN)-γ and autoantibody production. These are preventable and quenchable by pre- and post-induction treatment, respectively, using intradermal proinsulin-PIT injections. Intradermal proinsulin-PIT enhances proliferation of regulatory [forkhead box protein 3 (FoxP3(+))CD25(high) ] CD4 T cells, including those capable of proinsulin-specific regulation, suggesting this as its main mode of action. In contrast, peptide delivered intradermally on the surface of vitamin D3-modulated (tolerogenic) dendritic cells, controls autoimmunity in association with proinsulin-specific IL-10 production, but no change in regulatory CD4 T cells. These studies define a humanized, translational model for in vivo optimization of PIT to control autoimmunity in type 1 diabetes and indicate that dominant mechanisms of action differ according to mode of peptide delivery.

Susceptibility to large-joint osteoarthritis (hip and knee) is associated with BAG6 rs3117582 SNP and the VNTR polymorphism in the second exon of the FAM46A gene on chromosome 6

Family with sequence similarity 46, member A (FAM46A) gene VNTR and BCL2-Associated Athanogene 6 (BAG6) gene rs3117582 polymorphisms were genotyped in a case-control study with 474 large-joint (hip and knee) osteoarthritis (OA) patients and 568 controls in Croatian population by candidate-gene approach for association with OA. We found that BAG6 rs3117582 SNP genotypes were associated with protection (major allele homozygote) and susceptibility (major-minor allele heterozygote) to OA. BAG6 rs3117582 major allele (A) was associated with reduced risk to OA while the minor allele (C) was associated with increased risk to OA. We identified 6 alleles harboring 2 to 7 repeats making 20 genotypes for FAM46A. A rare FAM46A VNTR genotype comprising VNTR alleles with four and seven repeats (c/f) was associated with increased OA risk in both genders. The genotype with four and six repeats (c/e) was also associated with increased risk to OA in males. A polymorphic FAM46A allele with six repeats (e) was associated with reduced risk to OA in females. Our results suggest association between the FAM46A gene, BAG6 gene and OA in Croatian population, respectively. This is the first study to show associations between these genetic loci and OA.

Teaching a Foreign Language in Schools for Blind and Visually Impaired Children

Blind and visually impaired children can be taught to speak, read, and write foreign languages if the techniques and materials are adapted to capitalize on their strengths, including excellent memory and good hearing. In this article, the author draws on the scant literature, his experience as a blind teacher in a school for the blind in Yugoslavia, and his tour of British schools for the blind to extrapolate general principles for successful teaching and the application of appropriate methods and approaches.