Combined In Silico, Ex Vivo, and In Vivo Assessment of L-17, a Thiadiazine Derivative with Putative Neuro- and Cardioprotective and Antidepressant Effects.

Depression associated with poor general medical condition, such as post-stroke (PSD) or post-myocardial infarction (PMID) depression, is characterized by resistance to classical antidepressants. Special treatment strategies should thus be developed for these conditions. Our study aims to investigate the mechanism of action of 2-morpholino-5-phenyl-6H-1,3,4-thiadiazine, hydrobromide (L-17), a recently designed thiadiazine derivative with putative neuro- and cardioprotective and antidepressant-like effects, using combined in silico (for prediction of the molecular binding mechanisms), ex vivo (for assessment of the neural excitability using c-Fos immunocytochemistry), and in vivo (for direct examination of the neuronal excitability) methodological approaches. We found that the predicted binding affinities of L-17 to serotonin (5-HT) transporter (SERT) and 5-HT3 and 5-HT1A receptors are compatible with selective 5-HT serotonin reuptake inhibitors (SSRIs) and antagonists of 5-HT3 and 5-HT1A receptors, respectively. L-17 robustly increased c-Fos immunoreactivity in the amygdala and decreased it in the hippocampus. L-17 dose-dependently inhibited 5-HT neurons of the dorsal raphe nucleus; this inhibition was partially reversed by the 5-HT1A antagonist WAY100135. We suggest that L-17 is a potent 5-HT reuptake inhibitor and partial antagonist of 5-HT3 and 5-HT1A receptors; the effects of L-17 on amygdaloid and hippocampal excitability might be mediated via 5-HT, and putatively mediate the antidepressant-like effects of this drug. Since L-17 also possesses neuro- and cardioprotective properties, it can be beneficial in PSD and PMID. Combined in silico predictions with ex vivo neurochemical and in vivo electrophysiological assessments might be a useful strategy for early assessment of the efficacy and neural mechanism of action of novel CNS drugs.

Hexobarbital Sleep Test for Predicting the Susceptibility or Resistance to Experimental Posttraumatic Stress Disorder.

Hexobarbital sleep test (HST) was performed in male Wistar rats (hexobarbital 60 mg/kg, i.p.) 30 days prior to stress exposure. Based on the duration of hexobarbital-induced sleep, rats were divided into two groups, animals with high intensity (fast metabolizers (FM), sleep duration <15 min) or low intensity of hexobarbital metabolism (slow metabolizers (SM), sleep duration ≥15 min). The SM and FM groups were then divided into two subgroups: unstressed and stressed groups. The stressed subgroups were exposed to predator scent stress for 10 days followed by 15 days of rest. SM and FM rats from the unstressed group exhibited different behavioral and endocrinological patterns. SM showed greater anxiety and higher corticosterone levels. In stressed animals, anxiety-like posttraumatic stress disorder (PTSD) behavior was aggravated only in SM. Corticosterone levels in the stressed FM, PTSD-resistant rats, were lower than in unstressed SM. Thus, HST was able to predict the susceptibility or resistance to experimental PTSD, which was consistent with the changes in glucocorticoid metabolism.

Low glucocorticoids in stress-related disorders: the role of inflammation.

There is evidence that plasma cortisol concentration can be either increased or decreased in patients with depression and related anxiety and stress-related disorders; the exact pathophysiological mechanisms of this state are not almost clear. Several distinct theories were proposed and mechanisms, which could lead to decreased glucocorticoid signaling and/or levels, were described. However, there is a possible drawback in almost all the theories proposed: insufficient attention to the inflammatory process, which is undoubtedly present in several stress-related disorders, including post-traumatic stress disorder (PTSD). Previous studies only briefly mentioned the presence of an inflammatory reaction's signs in PTSD, without giving it due importance, although recognizing that it can affect the course of the disease. With that, the state of biochemical changes, characterized by the low glucocorticoids, glucocorticoid receptor's resistance and the signs of the persistent inflammation (with the high levels of circulating cytokines) might be observed not only in PTSD but in coronary heart diseases and systemic chronic inflammatory diseases (rheumatoid arthritis) as well. That is why the present review aims to depict the pathophysiological mechanisms, which lead to a decrease in glucocorticoids in PTSD due to the action of inflammatory stimuli. We described changes in the glucocorticoid system and inflammatory reaction as parts of an integral system, where glucocorticoids and the glucocorticoid receptor reside at the apex of a regulatory network that blocks several inflammatory pathways, while decreased glucocorticoid signaling and/or level leads to unchecked inflammatory reactions to promote pathologies such as PTSD. LAY SUMMARY This review emphasizes the importance of inflammatory reaction in the development of puzzling conditions sometimes observed in severe diseases including post-traumatic stress disorder - the decreased levels of glucocorticoids in the blood. Following the classical concepts, one would expect an increase in glucocorticoid hormones, since they are part of the feedback mechanism in the immune system, which reduces stress and inflammation. However, low levels of glucocorticoid hormones are also observed. Thus, this review describes potential mechanisms, which can lead to the development of such a state.

Pathological changes in the cellular structures of retina and choroidea in the early stages of alloxan-induced diabetes.

AIM: To investigate the temporal sequence of pathological changes in the cellular structures of retina and choroidea in the early stages of diabetes in laboratory animals. METHODS: Experimental type 1 diabetes was modeled by three intraperitoneal injections of an alloxan solution into 30 male nonlinear rats at 16 wk of age. The 30th and 60th days from the final alloxan injection were chosen as the endpoints. Light and electron microscopy and morphometric and immunohistochemical studies were performed on histological slices of eyeballs from experimental animals. RESULTS: Diabetic disturbances progressed to 60 d of the experiment. Thus, in the retina, a partial destruction of photoreceptors accompanied by interstitial edema was observed. The morphometric analysis revealed a reduction in the thickness of the retina. A reduction in the number of blood vessels of the choroid with disturbances of the endothelial cells and the vascular walls and a persistent reduction in the number of melanocytes were observed. The number of proliferating Ki-67 positive cells decreased, and the number of macrophages increased with diabetes development. CONCLUSION: The starting point in the development of destructive changes involves early reduction in the number of melanocytes of the choroidea and alterations in the retinal pigment epithelium.

Immunomodulatory Action of Substituted 1,3,4-Thiadiazines on the Course of Myocardial Infarction.

This review focuses on the biological action of the compounds from the group of substituted 1,3,4-thiadiazines on stress response and myocardial infarction. The aim of this review is to propose the possible mechanisms of action of 1,3,4-thiadiazines and offer prospectives in the development of new derivatives as therapeutic agents. It is known, that compounds that have biological effects similar to those used as antidepressants can down-regulate the secretion of proinflammatory cytokines, up-regulate the release of anti-inflammatory ones and affect cell recruitment, which allows them to be considered immunomodulators as well. The results of pharmacological evaluation, in silico studies, and in vivo experiments of several compounds from the group of substituted 1,3,4-thiadiazines with antidepressant properties are presented. It is proposed that the cardioprotective effects of substituted 1,3,4-thiadiazines might be explained by the peculiarities of their multi-target action: the ability of the compounds to interact with various types of receptors and transporters of dopaminergic, serotonergic and acetylcholinergic systems and to block the kinase signal pathway PI3K-AKT. The described effects of substituted 1,3,4-thiadiazines suggest that it is necessary to search for a new agents for limiting the peripheral inflammatory/ischemic damage through the entral mechanisms of stress reaction and modifying pro-inflammatory cytokine signaling pathways in the brain.

Effects of 1,3,4-thiadiazine compound with antidepressant properties in ligation model of acute pancreatitis.

Based on hypotheses concerning the role of stress in acute pancreatitis development, the experimental approach for the decrease stress damage via the use the compound with proven antistress/neuroleptic action was conducted. The study was aimed to discover 2-morpholino-5-phenyl-6H-1,3,4-thiadiazine hydrobromide (compound L-17) therapeutic action in experimental acute pancreatitis. The experimental model used was the ligation model. The trial was carried out on 50 male Wistar rats with average body weight 180-240 g. Histological picture of the pancreas was studied and biochemical and enzyme-immunoassays were carried out on the first and seventh days. The significant reduction in mortality on the background of L-17 compound administration was observed. While levels of all cytokines increased in induced experimental acute pancreatitis groups, the cytokine level rise was decreased when compound L-17 was administered. On the cellular level, the study revealed L-17's ability to prevent granulocytosis and decrease granulocytes infiltration to inflammatory foci. The decrease in inflammatory reaction magnitude and prevention of abscess formation in experimental acute pancreatitis accompanied by sistemic inflamamtion was due to L-17's ability to reduce neutrophilia and neutrophil entry into the injury zone.

Prevalence of arrhythmias in patients with type 2 diabetes and the role of structural changes in myocardium in their development.

OBJECTIVE: The aim of the study was to evaluate the prevalence of arrhythmias in patients with type 2 diabetes and their relationships with the structural parameters of the heart. METHODS: A retrospective case-control study was conducted using clinical and biochemical profiles of patients with diabetes at the Endocrinology Centre and City Clinical Hospital No. 40, Ekaterinburg, Russia. RESULTS: The total study sample included 75 subjects. The average age (SD) was 48.2 (5.6) years, and the mean duration of diabetes (SD) was 6.2 (2.4) years. The most common type of extrasystoles were the single supraventricular extrasystoles, observed in 72.29% of cases (vs 38.89% in the control group) and paired supraventricular extrasystoles, which were identified in 30% of cases (vs 19.44% in the control group). Ventricular cardiac arrhythmias in the form of ventricular extrasystoles (VE) were identified in 25.71% of cases (13.89% in the control group). CONCLUSIONS: This study revealed the signs of the morphological restructuring of the right chambers of the heart and a relatively high prevalence of supraventricular arrhythmias in the early stages of type 2 diabetes. Moreover, according to the results, the incidence of some types of supraventricular arrhythmias and the occurrence of tachycardia episodes in patients with type 2 diabetes mostly depends on the restructuring of the right chambers of the heart, which may be caused by the peculiarities of the cardiac innervation, with the higher density of choline and adrenergic plexuses in the right chambers.

Stress cardiomyopathy: Is it limited to Takotsubo syndrome? Problems of definition.

In 2006, Takotsubo syndrome (TTC) was described as a distinct type of stress-induced cardiomyopathy (stress cardiomyopathy). However, when thinking about Takotsubo cardiomyopathy from the viewpoints of the AHA and ESC classifications, 2 possible problems may arise. The first potential problem is that a forecast of disease outcome is lacking in the ESC classification, whereas the AHA only states that 'outcome is favorable with appropriate medical therapy'. However, based on the literature data, one can make a general conclusion that occurrence of myocardial lesions in TTC (i.e., myocardial fibrosis and contraction-band necrosis) causes the same effects as in other diseases with similar levels of myocardial damage and should not be considered to have a lesser impact on mortality. To summarise, TTC can cause not only severe complications such as pulmonary oedema, cardiogenic shock, and dangerous ventricular arrhythmias, but also damage to the myocardium, which can result in the development of potentially fatal conditions even after the disappearance of LV apical ballooning. The second potential problem arises from the definition of TTC as a stress cardiomyopathy in the AHA classification. In fact, the main factors leading to TTC are stress and microvascular anginas, since, as has been already discussed, coronary spasm can cause myocardium stunning, resulting in persistent apical ballooning. Thus, based on this review, 3 distinct types of stress cardiomyopathies exist (variant angina, microvascular angina, and TTC), with poor prognosis. Adding these diseases to the classification of cardiomyopathies will facilitate diagnosis and preventive prolonged treatment, which should include intensive anti-stress therapy.

Pharmacologic Evaluation of Antidepressant Activity and Synthesis of 2-Morpholino-5-phenyl-6H-1,3,4-thiadiazine Hydrobromide.

Substituted thiadiazines exert a reliable therapeutic effect in treating stress, and a schematic description of their ability to influence all aspects of a stress response has been depicted. This study was conducted to pharmacologically evaluate compound L-17, a substituted thiadiazine, (2-morpholino-5-phenyl-6H-1,3,4-thiadiazine, hydrobromide) for possible anti-psychotic/antidepressant activity. Compound L-17 was synthesized by cyclocondensation of α-bromoacetophenone with the original morpholine-4-carbothionic acid hydrazide. Pharmacologic evaluations were conducted using methods described by E.F. Lavretskaya (1985), and in accordance with published guidelines for studying drugs for neuroleptic activity. Compound L-17 was evaluated for various possible mechanisms of action, including its effects on cholinergic system agonists/antagonists, dopaminergic neurotransmission, the adrenergic system, and 5-HT3 serotonin receptors. One or more of these mechanisms may be responsible for the beneficial effects shown by thiadiazine compounds in experiments conducted to evaluate their activity in models of acute stress and acute myocardial infarction.

Effect of a new class of compounds of the group of substituted 5R1, 6H2-1,3,4-thiadiazine-2-amines on the inflammatory and cytokine response in experimental myocardial infarction.

This study investigated the effects of the L-17 compound of the group of substituted 5R1, 6H2- 1,3,4-thiadiazine-2-amines on the immune response and the plasma level of circulating cytokines in acute myocardial infarction (MI) in rats. The study was based upon experimental work which demonstrated the role of local and systemic inflammatory reactions in MI. Acute MI in rats was induced by left coronary artery coagulation. Histological study of the myocardium sections has been carried out at the 1(th) and 7(th) days of the experimental myocardial infarction. Serum activity of creatine phosphokinase (CPK), aspartate aminotransferase (AST), isoenzymes 1 and 2 and lactate dehydroge nase (LDH1-2) were investigated at days 1(st)and 7(th). ELISA analysis for plasma cytokine levels was performed using commercially available test kits following the manufacturer's instructions. Biochemical analysis in animals with the administration of the L-17 compound after MI showed that the AST and CPK levels at days 5 and 7 of experiments did not differ significantly from the values of intact animals. In animals of the group with MI without the administration of the L-17 compound, the IL-1 level 8 times and the TNF level 7.8 times exceeded the normal indicators, while the use of L-17 compound in the therapy resulted in only 1.8 times increase of IL-1 level and 4.7 times increase of TNF level in comparison with the norm. Thus, the introduction of L-17 compound in case of experimental MI delays exudative/alternative phase of inflammation, accelerates granulocytic and decreased the inflammation and anti-inflammation interleukins level.

Novelty, stress, and biological roots in human market behavior.

Although studies examining the biological roots of human behavior have been conducted since the seminal work Kahneman and Tversky, crises and panics have not disappeared. The frequent occurrence of various types of crises has led some economists to the conviction that financial markets occasionally praise irrational judgments and that market crashes cannot be avoided a priori (Sornette 2009; Smith 2004). From a biological point of view, human behaviors are essentially the same during crises accompanied by stock market crashes and during bubble growth when share prices exceed historic highs. During those periods, most market participants see something new for themselves, and this inevitably induces a stress response in them with accompanying changes in their endocrine profiles and motivations. The result is quantitative and qualitative changes in behavior (Zhukov 2007). An underestimation of the role of novelty as a stressor is the primary shortcoming of current approaches for market research. When developing a mathematical market model, it is necessary to account for the biologically determined diphasisms of human behavior in everyday low-stress conditions and in response to stressors. This is the only type of approach that will enable forecasts of market dynamics and investor behaviors under normal conditions as well as during bubbles and panics.

New insights in to the treatment of myocardial infarction.

This study investigated the effects of the L-17 compound of the group of substituted 5R1, 6H2-1,3,4-thiadiazine-2-amines on the inflammatory cellular infiltration and myocardial remodelling which occurs after acute myocardial infarction (MI) in rats. The study is based upon recent clinical and experimental work which demonstrated the role of local and systemic inflammatory reactions in postinfarction remodelling. Acute MI in rats was induced by left coronary artery coagulation. Animals were sacrificed on day one, five and seven after MI induction. The myocardiumal samples were taken from all parts of the heart and examined by histology. This included areas of infarction, infraction and areas that were peri-infarctiom and left ventricular areas distant from the damaged tissues. Serum activity of creatine phosphokinase (CPK), aspartate aminotransferase (AST), isoenzymes 1 and 2 and lactate dehydrogenase (LDH1-2) were investigated on the same three days, before and in the process of MI development was investigated (at days 1, 5 and 7). The L-17 compound to not only decreased the area of initial infarction but also changed the pattern of inflammatory reaction in the affected myocardium fundamentally. Laboratory studies of effects of L-17 compound on the development and course of experimental MI showed that administration decreased blood AST and CPK levels significantly and provided useful the data about the correlation between the activity of these enzymes and the dimensions of the significantly necrotic area. In this model of experimental MI the use of the L-17 compound induced led to the replacement of the exudative destructive inflammation that is seen under standard conditions with a more cellular "productive" pattern of inflammation, with associated reduction in initial necrosis area and the, decrease in myocardial ischaemia and reperfusion injury may account for the accelerated repair process.